JP7600815B2 - Rotating Electric Machine - Google Patents

Description

The disclosure in this specification relates to rotating electrical machines.

Conventionally, a rotating electric machine is known that includes a field element including a magnet portion having multiple magnetic poles with alternating polarities in the circumferential direction, and an armature having a multi-phase armature winding. The armature is provided, for example, as a stator, and has a cylindrical stator core and a stator winding integrated with the stator core. Also, a technique is known in which the stator core is fitted and fixed to a cylindrical frame by shrink fitting or press fitting. However, when the stator core is fixed by shrink fitting or press fitting, there is a concern that a thermal load or mechanical load acts on the stator core, causing an overload. In response to this, a configuration is known in which the stator core is divided into multiple split cores in the circumferential direction (see, for example, Patent Document 1).

JP 2020-25438 A

However, in a configuration in which the stator core is divided into multiple split cores in the circumferential direction, no fixing force is generated in the radial direction, unlike a configuration in which the stator core is fixed by shrink fitting or press fitting. This creates a gap between the stator core and the frame, which can cause rattling and reduce heat dissipation from the stator to the frame.

The present invention was made in consideration of the above circumstances, and aims to provide a rotating electric machine that allows the armature core to be properly assembled.

The various aspects disclosed in this specification employ different technical means to achieve their respective objectives. The objectives, features, and advantages disclosed in this specification will become more apparent by reference to the following detailed description and the accompanying drawings.

Means 1 is
A field element having a plurality of magnetic poles;
a toothless armature including a multi-phase armature winding and an armature core provided integrally with the armature winding on the radially inner side or the radially outer side;
an armature holding member attached to one of the inner and outer radial sides of the armature core opposite to the armature winding;
a rotating electric machine including:
The armature core is formed into a cylindrical shape by a plurality of divided cores arranged in a circumferential direction,
Each of the split cores is attached to the armature holding member with a resin layer interposed between the armature holding member and each of the split cores.

In the rotating electric machine of the above configuration, the armature core is formed into a cylindrical shape by a plurality of split cores arranged in the circumferential direction, and each of these split cores is assembled to the armature holding member. In this case, unlike a configuration in which the annular armature core and the armature holding member are fitted and fixed by shrink fitting or press fitting, there is a concern that the gap between the armature core and the armature holding member may cause rattle and reduce heat dissipation from the armature side to the armature holding member. In this regard, since each split core is assembled to the armature holding member with a resin layer interposed between the armature holding member and each split core, it is possible to suppress inconveniences caused by the gap between the armature core and the armature holding member. In particular, when an armature with a teethless structure is used, there is a concern that the armature winding may be displaced due to rattle of the armature core (each split core) because the armature winding is not engaged with the teeth of the armature core, but such inconveniences are also suppressed. As a result, the armature core can be properly assembled.

In the second embodiment, the armature holding member and the divided core are provided with engaging portions that can be engaged in the circumferential direction at the radially opposing portions of the armature holding member and the divided core.

In the above configuration, the armature holding member and the split cores are provided with engagement portions that can be engaged in the circumferential direction at their radially opposing portions, thereby preventing the split cores from shifting in the circumferential direction relative to the armature holding member.

In the third embodiment, as in the first or second embodiment, the split core is made of multiple core sheets stacked in the axial direction, and is constructed by stacking two or more types of core sheets.

The above configuration makes it possible to realize split cores that require different configurations in the axial direction (core sheet stacking direction). For example, in a split core that has an engagement portion in one axial direction that allows engagement with an armature holding member, it is preferable that different types of core sheets are used in the portion that has the engagement portion and the portion that does not have the engagement portion. Also, in a split core that has a portion that axially faces the coil end portion of the armature winding, it is preferable that different types of core sheets are used in the portion that faces the coil end and the other portion.

In method 4, in any of methods 1 to 3, a fixing device is attached at least at one location between each of the split cores arranged in the circumferential direction with the tip end inserted into the armature holding member.

According to the above configuration, the circumferential position of each split core is restricted by a fastener that is assembled with its tip inserted into the armature holding member. This makes it possible to prevent the split core from being displaced in the circumferential direction.

In the fifth aspect, in any one of the first to third aspects, a fixing device is attached to the circumferential middle portion of at least one of the split cores arranged in the circumferential direction, with the tip end of the fixing device being inserted into the armature holding member.

According to the above configuration, the split cores are fixed to the armature holding member by a fastener attached to the circumferential middle of the split cores. This allows each split core to be fixed properly.

In a sixth aspect, in any of the first to fifth aspects, the armature winding has a phase winding consisting of a plurality of partial windings for each phase, and the partial windings have a pair of intermediate conductor parts spaced apart from each other in the circumferential direction and a transition part that is provided on one end side and the other end side in the axial direction and connects the pair of intermediate conductor parts in an annular manner, and the intermediate conductor parts of the different partial windings are arranged in close proximity to each other in the circumferential direction, and the circumferential dimension of the split core is the same as the circumferential width L of the partial windings, or is L×D when the circumferential dimension of the armature core is the width L×n, and D is a divisor of "n" other than 1 or n.

By making the circumferential dimension of the split core the same as the circumferential width L of the partial winding, it is possible to simplify the assembly of the partial winding to the split core. Alternatively, by making the circumferential dimension of the split core L x D when the circumferential dimension of the armature core is width L x n and D is a divisor of "n" other than 1 or n, it is also possible to simplify the assembly of the partial winding to the split core.

In a seventh aspect of the invention, in a sixth aspect, the plurality of partial windings include a partial winding that is arranged to straddle the boundary between two of the divided cores that are adjacent in the circumferential direction.

By arranging the partial winding so that it straddles the boundary between two circumferentially adjacent split cores, misalignment of the split cores at the boundary between the split cores is less likely to occur. This allows for optimal assembly of each split core.

In the eighth aspect, in the sixth or seventh aspect,
In the armature winding, one of the pair of intermediate conductor portions in the partial winding of another phase is disposed between the pair of intermediate conductor portions in the partial winding, and between the partial windings whose jumper portions overlap in the circumferential direction, the jumper portion of one partial winding is located on the radially inner side and the jumper portion of the other partial winding is located on the radially outer side,
the plurality of partial windings include a first partial winding in which the transition portion is located on the divided core side of either the inside or the outside in the radial direction, and a second partial winding in which the transition portion is located on the opposite side of the divided core of either the inside or the outside in the radial direction,
The first partial winding is arranged so that the boundaries between the split cores arranged in the circumferential direction correspond to the boundaries between the first partial windings in the circumferential direction, and the second partial winding is arranged so as to straddle the boundaries between the split cores arranged in the circumferential direction.

By configuring the multiple partial windings to include a first partial winding whose transition portion is on the split core side of the radial inside or outside, and a second partial winding whose transition portion is on the opposite side of the split core of the radial inside or outside, each partial winding can be suitably arranged without interfering with the transition portions of each partial winding. In addition, of the first partial winding and the second partial winding, the transition portion is on the split core side and the first partial winding is assembled to the split core first, so that both circumferential ends of the first partial winding correspond to both circumferential ends of the split core, making it easy to assemble each partial winding to each split core (armature core).

In a ninth aspect of any of the sixth to eighth aspects, the split core is provided with a fixing portion for fixing the partial winding.

The partial winding is fixed to the split core by a fixing portion provided on the split core. This allows the split core and partial winding to be appropriately assembled in an armature with a teethless structure.

In the method 10, in the method 9, an insulating member is attached to the jumper portion of the partial winding to insulate the partial windings from each other, and the insulating member is provided with a fixed portion that is fixed to the fixed portion.

By providing an insulating member at the jumper section of the partial windings, mutual insulation can be suitably achieved even in a configuration in which the jumper sections of each partial winding are arranged to overlap each other in the circumferential direction. In addition, by providing the insulating member with a fixed section that is fixed to the fixed section on the split core side, the insulating member can be given an insulating function that insulates the partial windings from each other and a function of fixing the partial windings to the split core.

In means 11, in any of means 6 to 10, the armature holding member has an opposing portion that faces the bridge portion of the partial winding, and a fixing portion that fixes the partial winding is provided on the opposing portion.

In a configuration that includes an armature holding member, a teethless armature core, and an armature winding, the armature holding member is provided on one side of the armature core in the radial direction, and the armature winding is provided on the other side. The partial winding is fixed to a fixing portion provided on an opposing portion of the armature holding member that faces the jumper portion. In this case, the split core is interposed between the armature holding member and the armature winding, and is held in a sandwiched state between the two by fixing the two. This prevents the split core from shifting out of position, and allows the split core to be properly assembled to the armature holding member.

In a method 12, in any of methods 1 to 11, each of the split cores arranged in the circumferential direction has overlapping portions at their circumferential ends that overlap each other in the radial direction.

This configuration makes it possible to suppress degradation of magnetic performance at the boundaries (joints) between each of the split cores in the armature core.

In a method 13, in any of methods 1 to 12, the split core is formed by stacking multiple core sheets in the axial direction, and the core sheets are stacked with a circumferential offset, forming steps on the circumferential end faces of the split core, and each of the split cores lined up in the circumferential direction is assembled to the armature holding member with the steps on the circumferential end faces engaged with each other.

In the above configuration, the split cores arranged in the circumferential direction are engaged with each other due to the steps on the circumferential end faces of the split cores formed by the circumferential misalignment of the core sheets. This makes it possible to suppress the deterioration of magnetic resistance in the armature core.

In the method 14, in any one of the methods 1 to 13, a second resin layer is provided between each of the split cores and the armature winding.

In the above configuration, a resin layer is formed between the armature holding member and each split core, and also between each split core and the armature winding. This allows heat generated in the armature winding to be effectively transferred to the armature holding member via each split core, improving heat dissipation.

1 is a perspective view showing an entire rotating electric machine according to a first embodiment; FIG. FIG. FIG. FIG. Cross-sectional view of the rotor. FIG. 4 is a partial cross-sectional view showing the cross-sectional structure of a magnet unit. FIG. 4 is a diagram showing the relationship between the electrical angle and the magnetic flux density of the magnet according to the embodiment. FIG. 13 is a graph showing the relationship between electrical angle and magnetic flux density for a magnet of a comparative example. FIG. FIG. FIG. 4 is a perspective view of the core assembly as viewed from one axial side. FIG. 4 is a perspective view of the core assembly as viewed from the other axial side. FIG. FIG. FIG. 4 is a circuit diagram showing a connection state of partial windings in each of three phase windings. FIG. 4 is a side view showing the first coil module and the second coil module side by side for comparison; FIG. 4 is a side view showing a first partial winding and a second partial winding arranged side by side for comparison; FIG. 4 is a diagram showing a configuration of a first coil module. Cross-sectional view taken along line 20-20 in FIG. FIG. FIG. 4 is a diagram showing the configuration of a second coil module. Cross-sectional view taken along line 23-23 in Figure 22(a). FIG. FIG. 13 is a diagram showing overlap positions of film materials when each coil module is aligned in the circumferential direction. FIG. 4 is a plan view showing a state in which the first coil module is assembled to the core assembly. FIG. 4 is a plan view showing the assembled state of the first coil module and the second coil module to the core assembly. FIG. 4 is a vertical cross-sectional view showing a fixed state by a fixing pin. FIG. FIG. 2 is a cross-sectional view showing a portion of a vertical cross section of the bus bar module. FIG. 4 is a perspective view showing a state in which the bus bar module is assembled to the stator holder. FIG. 4 is a longitudinal cross-sectional view of a fixing portion for fixing the bus bar module. FIG. 4 is a vertical cross-sectional view showing a state in which the relay member is attached to the housing cover. FIG. FIG. 2 is an electric circuit diagram showing a control system for a rotating electric machine. FIG. 4 is a functional block diagram showing a current feedback control process performed by a control device. FIG. 4 is a functional block diagram showing a torque feedback control process performed by the control device. FIG. 11 is a partial cross-sectional view showing a cross-sectional structure of a magnet unit in a modified example. FIG. 4 is a diagram showing the configuration of a stator unit having an inner rotor structure. FIG. 4 is a plan view showing the assembled state of the coil module to the core assembly. FIG. 13 is a perspective view showing an entire rotating electric machine according to a second embodiment. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. 4 is an exploded perspective view showing an insulating cover in a partial winding. FIG. FIG. 4 is an exploded perspective view showing an insulating cover in a partial winding. FIG. 4 is a plan view showing partial windings arranged side by side in the circumferential direction. FIG. 4 is a cross-sectional view showing a state in which the split core and the partial windings are assembled to the stator holder. FIG. FIG. 4 is a perspective view showing a state in which the partial winding and the divided core are integrated together. FIG. 13 is a diagram showing a modified example of a split core. FIG. 13 is a diagram showing a modified example of a split core. FIG. 13 is a diagram showing a modified example of a split core. FIG. 2 is an exploded cross-sectional view showing a rotating electric machine divided into a fixed portion and a rotating portion. 4 is a cross-sectional view showing a state in which the split core and the partial windings are assembled to the stator holder. FIG. 6A and 6B are diagrams showing a configuration for fixing split cores to a stator holder; 13A and 13B are diagrams showing partial windings of a modified example and their assembled state. 13A and 13B are diagrams showing partial windings of a modified example and their assembled state. 4 is a cross-sectional view showing a state in which the split core and the partial windings are assembled to the stator holder. FIG. FIG. 2 is a vertical cross-sectional view showing the configuration of a stator unit.

Several embodiments will be described with reference to the drawings. In several embodiments, functionally and/or structurally corresponding and/or associated parts may be given the same reference numerals. For corresponding and/or associated parts, the descriptions of other embodiments may be referred to.

The rotating electric machine in this embodiment is used, for example, as a vehicle power source. However, rotating electric machines can be widely used in industrial, vehicular, aircraft, home appliances, office automation equipment, and gaming machines. In the following embodiments, parts that are identical or equivalent to each other are given the same reference numerals in the drawings, and the explanations of the parts with the same reference numerals are used.

First Embodiment
The rotating electric machine 10 according to the present embodiment is a synchronous multi-phase AC motor with an outer rotor structure. The rotating electric machine 10 is generally shown in FIGS. 1 to 5. FIG. 1 is a perspective view showing the entire rotating electric machine 10, FIG. 2 is a plan view of the rotating electric machine 10, FIG. 3 is a longitudinal sectional view of the rotating electric machine 10 (sectional view taken along line 3-3 in FIG. 2), FIG. 4 is a transverse sectional view of the rotating electric machine 10 (sectional view taken along line 4-4 in FIG. 3), and FIG. 5 is an exploded sectional view showing components of the rotating electric machine 10 in an exploded manner. In the following description, in the rotating electric machine 10, the direction in which the rotating shaft 11 extends is defined as the axial direction, the direction extending radially from the center of the rotating shaft 11 is defined as the radial direction, and the direction extending circumferentially around the rotating shaft 11 is defined as the circumferential direction.

The rotating electric machine 10 is roughly divided into a rotating electric machine main body having a rotor 20, a stator unit 50, and a busbar module 200, and a housing 241 and a housing cover 242 that are provided to surround the rotating electric machine main body. All of these components are arranged coaxially with a rotating shaft 11 that is integrally provided with the rotor 20, and the rotating electric machine 10 is configured by assembling them in the axial direction in a predetermined order. The rotating shaft 11 is supported by a pair of bearings 12, 13 provided on the stator unit 50 and the housing 241, respectively, and is rotatable in this state. The bearings 12, 13 are, for example, radial ball bearings having an inner ring, an outer ring, and a number of balls arranged between them. The rotation of the rotating shaft 11 rotates, for example, the axle of a vehicle. The rotating electric machine 10 can be mounted on a vehicle by fixing the housing 241 to a vehicle frame or the like.

In the rotating electric machine 10, the stator unit 50 is provided to surround the rotating shaft 11, and the rotor 20 is disposed radially outside the stator unit 50. The stator unit 50 has a stator 60 and a stator holder 70 attached radially inside the stator 60. The rotor 20 and the stator 60 are disposed radially opposite each other with an air gap between them, and the rotor 20 rotates integrally with the rotating shaft 11, causing the rotor 20 to rotate radially outside the stator 60. The rotor 20 corresponds to the "field element" and the stator 60 corresponds to the "armature".

Figure 6 is a longitudinal cross-sectional view of the rotor 20. As shown in Figure 6, the rotor 20 has a rotor carrier 21 that is substantially cylindrical, and a ring-shaped magnet unit 22 fixed to the rotor carrier 21. The rotor carrier 21 has a cylindrical portion 23 and an end plate portion 24 provided at one axial end of the cylindrical portion 23, which are integrated together. The rotor carrier 21 functions as a magnet holding member, and the magnet unit 22 is fixed in a ring shape to the radial inside of the cylindrical portion 23. A through hole 24a is formed in the end plate portion 24, and the rotating shaft 11 is fixed to the end plate portion 24 by a fastener 25 such as a bolt while being inserted into the through hole 24a. The rotating shaft 11 has a flange 11a that extends in a direction that intersects (orthogonally) the axial direction, and the rotor carrier 21 is fixed to the rotating shaft 11 while the flange 11a and the end plate portion 24 are surface-jointed.

The magnet unit 22 has a cylindrical magnet holder 31, a plurality of magnets 32 fixed to the inner peripheral surface of the magnet holder 31, and an end plate 33 fixed to the axially opposite end plate portion 24 of the rotor carrier 21. The magnet holder 31 has the same length dimension as the magnet 32 in the axial direction. The magnet 32 is provided in a state in which it is surrounded by the magnet holder 31 from the radially outside. The magnet holder 31 and the magnet 32 are fixed in a state in which they abut against the end plate 33 at one end on the axial direction. The magnet unit 22 corresponds to the "magnet portion".

Figure 7 is a partial cross-sectional view showing the cross-sectional structure of magnet unit 22. In Figure 7, the direction of the easy magnetization axis of magnet 32 is indicated by an arrow.

In the magnet unit 22, the magnets 32 are arranged in a line so that their polarity alternates along the circumferential direction of the rotor 20. This gives the magnet unit 22 multiple magnetic poles in the circumferential direction. The magnets 32 are polar anisotropic permanent magnets, and are constructed using sintered neodymium magnets with an intrinsic coercive force of 400 kA/m or more and a residual magnetic flux density Br of 1.0 T or more.

The radially inner peripheral surface (stator 60 side) of magnet 32 is magnetic flux action surface 34 where magnetic flux is exchanged. In magnet unit 22, magnetic flux is generated intensively in the area near the d-axis, which is the magnetic pole center, on magnetic flux action surface 34 of magnet 32. Specifically, in magnet 32, the orientation of the magnetization easy axis is different on the d-axis side (part closer to the d-axis) and the q-axis side (part closer to the q-axis), and on the d-axis side, the orientation of the magnetization easy axis is parallel to the d-axis, and on the q-axis side, the orientation of the magnetization easy axis is perpendicular to the q-axis. In this case, an arc-shaped magnetic flux path is formed along the orientation of the magnetization easy axis. In short, magnet 32 is configured so that the orientation of the magnetization easy axis is parallel to the d-axis on the d-axis side, which is the magnetic pole center, compared to the q-axis side, which is the magnetic pole boundary.

In magnet 32, the magnetic flux path is formed in an arc shape, so the magnetic flux path length is longer than the radial thickness dimension of magnet 32. This increases the permeance of magnet 32, making it possible to exert the same performance as a magnet with a larger amount of magnet, despite the same amount of magnet.

The magnets 32 are arranged in pairs, two adjacent magnets in the circumferential direction, to form one magnetic pole. In other words, the magnets 32 arranged in the circumferential direction in the magnet unit 22 have cut surfaces on the d-axis and q-axis, and the magnets 32 are arranged in contact with or close to each other. As described above, the magnets 32 have an arc-shaped magnetic flux path, and the north pole and south pole of the magnets 32 adjacent to each other in the circumferential direction face each other on the q-axis. This makes it possible to improve the permeance near the q-axis. In addition, the magnets 32 on both sides of the q-axis attract each other, so that the magnets 32 can maintain contact with each other. This also contributes to improving the permeance.

In the magnet unit 22, the magnetic flux flows in an arc between the adjacent N and S poles due to each magnet 32, so the magnetic path is longer than that of a radially anisotropic magnet, for example. Therefore, as shown in FIG. 8, the magnetic flux density distribution is close to a sine wave. As a result, unlike the magnetic flux density distribution of a radially anisotropic magnet shown as a comparative example in FIG. 9, the magnetic flux can be concentrated toward the center of the magnetic pole, making it possible to increase the torque of the rotating electric machine 10. In addition, in the magnet unit 22 of this embodiment, it can be confirmed that there is a difference in the magnetic flux density distribution compared to the conventional Halbach array magnet. In addition, in FIG. 8 and FIG. 9, the horizontal axis indicates the electrical angle, and the vertical axis indicates the magnetic flux density. In addition, in FIG. 8 and FIG. 9, 90° on the horizontal axis indicates the d-axis (i.e., the magnetic pole center), and 0° and 180° on the horizontal axis indicate the q-axis.

In other words, with each magnet 32 configured as described above, the magnetic flux on the d-axis in the magnet unit 22 is strengthened, and the magnetic flux change near the q-axis is suppressed. This makes it possible to preferably realize a magnet unit 22 in which the surface magnetic flux change from the q-axis to the d-axis is smooth at each magnetic pole.

The sine wave matching rate of the magnetic flux density distribution may be, for example, 40% or more. In this way, the amount of magnetic flux in the central part of the waveform can be reliably improved compared to the use of radially aligned magnets or parallel aligned magnets, which have a sine wave matching rate of about 30%. Furthermore, if the sine wave matching rate is set to 60% or more, the amount of magnetic flux in the central part of the waveform can be reliably improved compared to a magnetic flux concentration arrangement such as a Halbach arrangement.

In the radially anisotropic magnet shown in FIG. 9, the magnetic flux density changes sharply near the q-axis. The sharper the change in magnetic flux density, the more eddy currents increase in the stator winding 61 of the stator 60, which will be described later. The magnetic flux changes sharply on the stator winding 61 side. In contrast, in this embodiment, the magnetic flux density distribution has a magnetic flux waveform that is close to a sine wave. Therefore, the change in magnetic flux density near the q-axis is smaller than the change in magnetic flux density of the radially anisotropic magnet. This makes it possible to suppress the generation of eddy currents.

The magnet 32 has a recess 35 formed on the outer peripheral surface on the radially outer side in a predetermined range including the d-axis, and a recess 36 formed on the inner peripheral surface on the radially inner side in a predetermined range including the q-axis. In this case, depending on the direction of the easy magnetization axis of the magnet 32, the magnetic flux path is short near the d-axis on the outer peripheral surface of the magnet 32, and the magnetic flux path is short near the q-axis on the inner peripheral surface of the magnet 32. Therefore, taking into consideration that it is difficult to generate sufficient magnetic flux in places where the magnetic flux path length is short in the magnet 32, magnets are removed in places where the magnetic flux is weak.

The magnet unit 22 may be configured to use the same number of magnets 32 as the number of magnetic poles. For example, the magnets 32 may be provided between two circumferentially adjacent magnetic poles, with one magnet being provided between the d-axis, which is the center of each magnetic pole. In this case, the magnet 32 is configured so that the circumferential center is the q-axis and has a cut surface on the d-axis. The magnet 32 may also be configured so that the circumferential center is the d-axis, rather than the q-axis. Instead of using magnets with twice the number of magnetic poles or the same number of magnets as the number of magnetic poles, the magnets 32 may be configured to use ring magnets connected in a ring shape.

As shown in FIG. 3, a resolver 41 is provided as a rotation sensor on both axial ends of the rotating shaft 11 opposite the connection with the rotor carrier 21 (the upper end in the figure). The resolver 41 includes a resolver rotor fixed to the rotating shaft 11 and a resolver stator arranged radially outside the resolver rotor to face it. The resolver rotor is in the shape of a circular ring, and is provided coaxially with the rotating shaft 11 with the rotating shaft 11 inserted through it. The resolver stator has a stator core and a stator coil, and is fixed to the housing cover 242.

Next, the configuration of the stator unit 50 will be described. Figure 10 is a perspective view of the stator unit 50, and Figure 11 is a vertical cross-sectional view of the stator unit 50. Note that Figure 11 is a vertical cross-sectional view taken at the same position as Figure 3.

The stator unit 50 generally comprises a stator 60 and a stator holder 70 located radially inside the stator 60. The stator 60 comprises a stator winding 61 and a stator core 62. The stator core 62 and the stator holder 70 are integrated together to form a core assembly CA, to which multiple partial windings 151 constituting the stator winding 61 are attached. The stator winding 61 corresponds to the "armature winding", the stator core 62 corresponds to the "armature core", and the stator holder 70 corresponds to the "armature holding member". The core assembly CA corresponds to the "support member".

Here, we will first explain the core assembly CA. Figure 12 is a perspective view of the core assembly CA seen from one axial side, Figure 13 is a perspective view of the core assembly CA seen from the other axial side, Figure 14 is a cross-sectional view of the core assembly CA, and Figure 15 is an exploded cross-sectional view of the core assembly CA.

As described above, the core assembly CA has the stator core 62 and the stator holder 70 attached to its radially inner side. In other words, the stator core 62 is integrally attached to the outer peripheral surface of the stator holder 70.

The stator core 62 is configured as a core sheet laminate in which core sheets 62a made of magnetic steel sheets are laminated in the axial direction, and has a cylindrical shape with a predetermined thickness in the radial direction. The stator winding 61 is attached to the radially outer side of the stator core 62, which is the rotor 20 side. The outer peripheral surface of the stator core 62 is curved without any irregularities. The stator core 62 functions as a back yoke. The stator core 62 is configured by laminating multiple core sheets 62a, for example, punched into an annular plate shape, in the axial direction. However, a stator core 62 having a helical core structure may also be used. In the helical core structure stator core 62, a strip-shaped core sheet is used, and this core sheet is wound in an annular shape and laminated in the axial direction to form a cylindrical stator core 62 as a whole.

In this embodiment, the stator 60 has a slotless structure that does not have teeth for forming slots, but the configuration may be any of the following (A) to (C).
(A) In the stator 60, inter-conductor members are provided between each conductor portion (intermediate conductor portion 152 described later) in the circumferential direction, and the inter-conductor member is made of a magnetic material that satisfies the relationship Wt×Bs≦Wm×Br, where Wt is the circumferential width of the inter-conductor member at one magnetic pole, Bs is the saturation magnetic flux density of the inter-conductor member, Wm is the circumferential width of the magnet 32 at one magnetic pole, and Br is the residual magnetic flux density of the magnet 32.
(B) In the stator 60, inter-conductor members are provided between each conductor portion (intermediate conductor portion 152) in the circumferential direction, and a non-magnetic material is used for the inter-conductor members.
(C) In the stator 60, no inter-conductor members are provided between each conductor portion (intermediate conductor portion 152) in the circumferential direction.

As shown in FIG. 15, the stator holder 70 has an outer cylinder member 71 and an inner cylinder member 81, which are assembled together with the outer cylinder member 71 on the radial outside and the inner cylinder member 81 on the radial inside. Each of these members 71, 81 is made of metal, such as aluminum or cast iron, or carbon fiber reinforced plastic (CFRP).

The outer tube member 71 is a cylindrical member whose outer and inner circumferential surfaces are both perfectly circular curved surfaces, and an annular flange 72 extending radially inward is formed on one axial end side. This flange 72 has a plurality of protrusions 73 extending radially inward at a predetermined interval in the circumferential direction (see FIG. 13). In addition, opposing surfaces 74, 75 that axially face the inner tube member 81 are formed on one and the other axial ends of the outer tube member 71, and annular grooves 74a, 75a extending annularly are formed on the opposing surfaces 74, 75.

The inner tube member 81 is a cylindrical member having an outer diameter smaller than the inner diameter of the outer tube member 71, and its outer peripheral surface is a perfectly circular curved surface concentric with the outer tube member 71. An annular flange 82 extending radially outward is formed on one axial end of the inner tube member 81. The inner tube member 81 is assembled to the outer tube member 71 in a state in which it abuts against the opposing surfaces 74, 75 of the outer tube member 71 in the axial direction. As shown in FIG. 13, the outer tube member 71 and the inner tube member 81 are assembled to each other by a fastener 84 such as a bolt. Specifically, a plurality of protrusions 83 extending radially inward are formed at a predetermined interval in the circumferential direction on the inner peripheral side of the inner tube member 81, and the protrusions 73, 83 are fastened to each other by a fastener 84 in a state in which the axial end faces of the protrusions 83 and the protrusions 73 of the outer tube member 71 are overlapped.

As shown in FIG. 14, when the outer tube member 71 and the inner tube member 81 are assembled to each other, an annular gap is formed between the inner peripheral surface of the outer tube member 71 and the outer peripheral surface of the inner tube member 81, and the gap space serves as a refrigerant passage 85 through which a refrigerant such as cooling water flows. The refrigerant passage 85 is provided in an annular shape in the circumferential direction of the stator holder 70. More specifically, the inner tube member 81 is provided with a passage forming portion 88 that protrudes radially inward on its inner peripheral side and has an inlet side passage 86 and an outlet side passage 87 formed therein, and each of these passages 86, 87 opens to the outer peripheral surface of the inner tube member 81. In addition, a partition portion 89 is provided on the outer peripheral surface of the inner tube member 81 to divide the refrigerant passage 85 into an inlet side and an outlet side. As a result, the refrigerant flowing in from the inlet side passage 86 flows in the circumferential direction through the refrigerant passage 85, and then flows out from the outlet side passage 87.

The inlet side passage 86 and the outlet side passage 87 have one end extending radially and opening on the outer circumferential surface of the inner cylinder member 81, and the other end extending axially and opening on the axial end surface of the inner cylinder member 81. FIG. 12 shows an inlet opening 86a leading to the inlet side passage 86 and an outlet opening 87a leading to the outlet side passage 87. The inlet side passage 86 and the outlet side passage 87 lead to an inlet port 244 and an outlet port 245 (see FIG. 1) attached to the housing cover 242, and the refrigerant flows in and out through these ports 244, 245.

At the joint between the outer cylinder member 71 and the inner cylinder member 81, sealing materials 101, 102 are provided to prevent leakage of the refrigerant from the refrigerant passage 85 (see FIG. 15). Specifically, the sealing materials 101, 102 are, for example, O-rings, and are accommodated in the annular grooves 74a, 75a of the outer cylinder member 71 and are provided in a compressed state by the outer cylinder member 71 and the inner cylinder member 81.

12, the inner tube member 81 has an end plate portion 91 at one axial end, and the end plate portion 91 is provided with a hollow cylindrical boss portion 92 extending in the axial direction. The boss portion 92 is provided so as to surround an insertion hole 93 for inserting the rotating shaft 11. The boss portion 92 is provided with a plurality of fastening portions 94 for fixing the housing cover 242. The end plate portion 91 is provided with a plurality of support portions 95 extending in the axial direction on the radial outside of the boss portion 92. The support portions 95 are portions that serve as fixing portions for fixing the bus bar module 200, and will be described in detail later. The boss portion 92 is a bearing holding member that holds the bearing 12, and the bearing 12 is fixed to a bearing fixing portion 96 provided on the inner periphery of the boss portion 92 (see FIG. 3).

As shown in Figures 12 and 13, the outer tube member 71 and the inner tube member 81 are formed with recesses 105, 106 that are used to secure multiple coil modules 150, which will be described later.

Specifically, as shown in FIG. 12, a plurality of recesses 105 are formed at equal intervals in the circumferential direction on the axial end face of the inner tube member 81, more specifically, on the axial outer end face of the end plate portion 91 that surrounds the boss portion 92. Also, as shown in FIG. 13, a plurality of recesses 106 are formed at equal intervals in the circumferential direction on the axial end face of the outer tube member 71, more specifically, on the axial outer end face of the flange 72. These recesses 105, 106 are arranged so as to be aligned on an imaginary circle that is concentric with the core assembly CA. The recesses 105, 106 are each provided at the same position in the circumferential direction, and the intervals and numbers are also the same.

The stator core 62 is assembled in a state where it generates a radial compressive force on the stator holder 70 in order to ensure the strength of the assembly to the stator holder 70. Specifically, the stator core 62 is fitted and fixed to the stator holder 70 with a predetermined tightening margin by shrink fitting or press fitting. In this case, it can be said that the stator core 62 and the stator holder 70 are assembled in a state where one of them generates a radial stress on the other. In addition, when increasing the torque of the rotating electric machine 10, for example, it is considered that the diameter of the stator 60 is increased, and in such a case, the tightening force of the stator core 62 is increased to strengthen the connection of the stator core 62 to the stator holder 70. However, if the compressive stress (in other words, the residual stress) of the stator core 62 is increased, there is a concern that the stator core 62 may be damaged.

In this embodiment, the stator core 62 and the stator holder 70 are fitted and fixed to each other with a predetermined tightening margin, and a restricting portion is provided at the radially opposing portions of the stator core 62 and the stator holder 70 to restrict the circumferential displacement of the stator core 62 by engaging in the circumferential direction. In other words, as shown in Figures 12 to 14, a plurality of engaging members 111 are provided as restricting portions at a predetermined interval in the circumferential direction between the stator core 62 and the outer tube member 71 of the stator holder 70 in the radial direction, and the engaging members 111 suppress the circumferential positional deviation between the stator core 62 and the stator holder 70. In this case, it is preferable to provide a recess in at least one of the stator core 62 and the outer tube member 71, and to engage the engaging member 111 in the recess. Instead of the engaging member 111, a convex portion may be provided in either the stator core 62 or the outer tube member 71.

In the above configuration, the stator core 62 and the stator holder 70 (outer tube member 71) are fitted and fixed with a predetermined tightening margin, and are provided in a state in which their mutual circumferential displacement is restricted by the restriction of the engaging member 111. Therefore, even if the tightening margin in the stator core 62 and the stator holder 70 is relatively small, the circumferential displacement of the stator core 62 can be suppressed. In addition, since the desired displacement suppression effect can be obtained even if the tightening margin is relatively small, damage to the stator core 62 caused by an excessively large tightening margin can be suppressed. As a result, the displacement of the stator core 62 can be appropriately suppressed.

A ring-shaped internal space is formed on the inner periphery of the inner cylinder member 81 so as to surround the rotating shaft 11, and electrical components constituting, for example, an inverter as a power converter may be arranged in the internal space. The electrical components are, for example, electrical modules in which semiconductor switching elements and capacitors are packaged. By arranging the electrical module in contact with the inner periphery of the inner cylinder member 81, it is possible to cool the electrical module by the refrigerant flowing through the refrigerant passage 85. It is also possible to eliminate the multiple protrusions 83 on the inner periphery of the inner cylinder member 81 or to reduce the protruding height of the protrusions 83, thereby expanding the internal space on the inner periphery of the inner cylinder member 81.

Next, the configuration of the stator winding 61 that is assembled to the core assembly CA will be described in detail. The state in which the stator winding 61 is assembled to the core assembly CA is as shown in Figures 10 and 11, where the multiple partial windings 151 that make up the stator winding 61 are assembled in a circumferentially aligned state on the radial outside of the core assembly CA, i.e., on the radial outside of the stator core 62.

The stator winding 61 has multiple phase windings, and is formed into a cylindrical (annular) shape by arranging the phase windings of each phase in a predetermined order in the circumferential direction. In this embodiment, the stator winding 61 is configured to have three phase windings by using U-phase, V-phase, and W-phase windings.

As shown in FIG. 11, the stator 60 has, in the axial direction, a portion corresponding to the coil side CS that faces radially the magnet unit 22 of the rotor 20, and a portion corresponding to the coil end CE that is axially outside the coil side CS. In this case, the stator core 62 is provided in a range corresponding to the coil side CS in the axial direction.

In the stator winding 61, each phase winding has a plurality of partial windings 151 (see FIG. 16), and the partial windings 151 are individually provided as coil modules 150. In other words, the coil module 150 is configured by integrally providing the partial windings 151 in the phase winding of each phase, and the stator winding 61 is configured by a predetermined number of coil modules 150 according to the number of poles. The coil modules 150 (partial windings 151) of each phase are arranged in a predetermined order in the circumferential direction, so that the conductor parts of each phase are arranged in a predetermined order on the coil side CS of the stator winding 61. FIG. 10 shows the order of the conductor parts of the U-phase, V-phase, and W-phase on the coil side CS. In this embodiment, the number of magnetic poles is 24, but the number is arbitrary.

In the stator winding 61, the partial windings 151 of each coil module 150 are connected in parallel or in series for each phase to form a phase winding. Figure 16 is a circuit diagram showing the connection state of the partial windings 151 in each of the three phase windings. Figure 16 shows the partial windings 151 in the phase windings of each phase connected in parallel.

As shown in FIG. 11, the coil module 150 is assembled to the radial outside of the stator core 62. In this case, the coil module 150 is assembled with both axial end portions protruding axially outward from the stator core 62 (i.e., toward the coil end CE). In other words, the stator winding 61 has a portion corresponding to the coil end CE that protrudes axially outward from the stator core 62, and a portion corresponding to the coil side CS that is axially inward from that.

The coil module 150 has two types of shapes. One has a shape in which the partial winding 151 is bent radially inward at the coil end CE, i.e., toward the stator core 62, and the other has a shape in which the partial winding 151 is not bent radially inward at the coil end CE and extends linearly in the axial direction. In the following description, for convenience, the partial winding 151 having a bent shape at both axial ends is also referred to as the "first partial winding 151A," and the coil module 150 having the first partial winding 151A is also referred to as the "first coil module 150A." The partial winding 151 not having a bent shape at both axial ends is also referred to as the "second partial winding 151B," and the coil module 150 having the second partial winding 151B is also referred to as the "second coil module 150B."

Figure 17 is a side view showing the first coil module 150A and the second coil module 150B side by side for comparison, and Figure 18 is a side view showing the first partial winding 151A and the second partial winding 151B side by side for comparison. As shown in these figures, the coil modules 150A, 150B and the partial windings 151A, 151B have different axial lengths and different end shapes on both axial sides. The first partial winding 151A is approximately C-shaped in side view, and the second partial winding 151B is approximately I-shaped in side view. The first partial winding 151A is fitted with insulating covers 161, 162 as "first insulating covers" on both axial sides, and the second partial winding 151B is fitted with insulating covers 163, 164 as "second insulating covers" on both axial sides.

Next, the configuration of coil modules 150A and 150B will be described in detail.

First, we will explain the first coil module 150A of the coil modules 150A and 150B. Figure 19(a) is a perspective view showing the configuration of the first coil module 150A, and Figure 19(b) is a perspective view showing the components of the first coil module 150A disassembled. Also, Figure 20 is a cross-sectional view taken along line 20-20 in Figure 19(a).

As shown in Figures 19(a) and 19(b), the first coil module 150A has a first partial winding 151A formed by multiple windings of conductive wire CR, and insulating covers 161, 162 attached to one axial end and the other axial end of the first partial winding 151A. The insulating covers 161, 162 are molded from an insulating material such as synthetic resin.

The first partial winding 151A has a pair of intermediate conductor parts 152 arranged parallel to each other and linearly, and a pair of transition parts 153A that connect the pair of intermediate conductor parts 152 at both axial ends, and is formed into a ring shape by the pair of intermediate conductor parts 152 and the pair of transition parts 153A. The pair of intermediate conductor parts 152 are arranged at a predetermined coil pitch apart, and the intermediate conductor parts 152 of the partial winding 151 of the other phase can be arranged between the pair of intermediate conductor parts 152 in the circumferential direction. In this embodiment, the pair of intermediate conductor parts 152 are arranged at a two coil pitch apart, and one intermediate conductor part 152 of the partial winding 151 of the other two phases is arranged between the pair of intermediate conductor parts 152.

The pair of transition sections 153A have the same shape on both axial sides, and both are provided as parts corresponding to the coil ends CE (see FIG. 11). Each transition section 153A is provided so as to be bent in a direction perpendicular to the intermediate conductor section 152, i.e., in a direction perpendicular to the axial direction.

As shown in FIG. 18, the first partial winding 151A has a crossover portion 153A on both axial sides, and the second partial winding 151B has a crossover portion 153B on both axial sides. The crossover portions 153A, 153B of the partial windings 151A, 151B have different shapes, and to clearly distinguish between them, the crossover portion 153A of the first partial winding 151A is also referred to as the "first crossover portion 153A," and the crossover portion 153B of the second partial winding 151B is also referred to as the "second crossover portion 153B."

In each partial winding 151A, 151B, the intermediate conductor portions 152 are provided as coil side conductor portions arranged one by one in the circumferential direction on the coil side CS. In addition, each transition portion 153A, 153B is provided as a coil end conductor portion that connects intermediate conductor portions 152 of the same phase at two different positions in the circumferential direction on the coil end CE.

As shown in FIG. 20, the first partial winding 151A is formed by winding the conductor wire CR in multiple layers so that the cross section of the conductor assembly portion is rectangular. FIG. 20 shows a cross section of the intermediate conductor portion 152, in which the conductor wire CR is wound in multiple layers so as to be aligned in the circumferential and radial directions. In other words, the first partial winding 151A is formed so that the conductor wire CR is arranged in multiple rows in the circumferential direction and multiple rows in the radial direction in the intermediate conductor portion 152, so that the cross section is approximately rectangular. In addition, at the tip of the first crossover portion 153A, the conductor wire CR is wound in multiple layers so as to be aligned in the axial and radial directions by bending in the radial direction. In this embodiment, the first partial winding 151A is formed by winding the conductor wire CR in a concentric manner. However, the winding method of the conductor wire CR is arbitrary, and instead of concentric winding, the conductor wire CR may be wound multiple times using alpha winding.

In the first partial winding 151A, an end of the conductor wire CR is pulled out from one of the first crossover parts 153A on both axial sides (the upper first crossover part 153A in FIG. 19(b)), and these ends serve as winding ends 154, 155. The winding ends 154, 155 are the start and end of the winding of the conductor wire CR, respectively. One of the winding ends 154, 155 is connected to a current input/output terminal, and the other is connected to a neutral point.

In the first partial winding 151A, each intermediate conductor portion 152 is provided covered with a sheet-like insulating cover 157. Note that in FIG. 19(a), the first coil module 150A is shown in a state in which the intermediate conductor portion 152 is covered with the insulating cover 157 and the intermediate conductor portion 152 is present inside the insulating cover 157, but for convenience, the corresponding portion is referred to as the intermediate conductor portion 152 (the same applies to FIG. 22(a) described below).

The insulating cover 157 is provided by using a film material FM having an axial dimension of at least the length of the axial insulating cover range of the intermediate conductor portion 152, and wrapping the film material FM around the intermediate conductor portion 152. The film material FM is made of, for example, a PEN (polyethylene naphthalate) film. More specifically, the film material FM includes a film base material and a foaming adhesive layer provided on one of the two surfaces of the film base material. The film material FM is then wrapped around the intermediate conductor portion 152 while being adhered to the intermediate conductor portion 152 by the adhesive layer. It is also possible to use a non-foaming adhesive as the adhesive layer.

20, the intermediate conductor portion 152 has a substantially rectangular cross section due to the conductor material CR arranged in the circumferential and radial directions, and the intermediate conductor portion 152 is covered with a film material FM with its circumferential ends overlapped to provide an insulating cover 157. The film material FM is a rectangular sheet whose vertical dimension is longer than the axial length of the intermediate conductor portion 152 and whose horizontal dimension is longer than the circumference of the intermediate conductor portion 152, and is wound around the intermediate conductor portion 152 with creases made to match the cross-sectional shape of the intermediate conductor portion 152. When the film material FM is wound around the intermediate conductor portion 152, the gap between the conductor material CR of the intermediate conductor portion 152 and the film base material is filled by foaming in the adhesive layer. In addition, in the overlap portion OL of the film material FM, the circumferential ends of the film material FM are joined together by an adhesive layer.

The intermediate conductor portion 152 is provided with an insulating cover 157 so as to cover all of the two circumferential side surfaces and two radial side surfaces. In this case, the insulating cover 157 surrounding the intermediate conductor portion 152 is provided with an overlap portion OL where the film material FM overlaps the portion facing the intermediate conductor portion 152 in the partial winding 151 of the other phase, i.e., one of the two circumferential side surfaces of the intermediate conductor portion 152. In this embodiment, the overlap portion OL is provided on the same circumferential side of each of the pair of intermediate conductor portions 152.

In the first partial winding 151A, an insulating cover 157 is provided in the range from the intermediate conductor portion 152 to the portion of the first crossover portion 153A on both axial sides that is covered by the insulating covers 161, 162 (i.e., the portion inside the insulating covers 161, 162). In FIG. 17, the range AX1 in the first coil module 150A is the portion not covered by the insulating covers 161, 162, and the insulating cover 157 is provided in a range extending above and below the range AX1.

Next, the configuration of the insulating covers 161 and 162 will be described.

The insulating cover 161 is attached to the first crossover portion 153A on one axial side of the first partial winding 151A, and the insulating cover 162 is attached to the first crossover portion 153A on the other axial side of the first partial winding 151A. The configuration of the insulating cover 161 is shown in Figures 21(a) and (b). Figures 21(a) and (b) are perspective views of the insulating cover 161 viewed from two different directions.

21(a) and (b), the insulating cover 161 has a pair of side portions 171 that are circumferential side surfaces, an outer surface portion 172 on the axially outer side, an inner surface portion 173 on the axially inner side, and a front surface portion 174 on the radially inner side. Each of these portions 171 to 174 is formed in a plate shape and is connected to each other in a three-dimensional shape so that only the radially outer side is open. Each of the pair of side portions 171 is provided in a direction that extends toward the axis of the core assembly CA when assembled to the core assembly CA. Therefore, when multiple first coil modules 150A are arranged in a circumferential line, the side portions 171 of the insulating cover 161 of each adjacent first coil module 150A face each other in abutment or close proximity. This allows each of the first coil modules 150A adjacent in the circumferential direction to be insulated from each other while being preferably arranged in an annular arrangement.

In the insulating cover 161, the outer surface portion 172 is provided with an opening 175a for pulling out the winding end 154 of the first partial winding 151A, and the front surface portion 174 is provided with an opening 175b for pulling out the winding end 155 of the first partial winding 151A. In this case, one winding end 154 is pulled out axially from the outer surface portion 172, while the other winding end 155 is pulled out radially from the front surface portion 174.

In addition, in the insulating cover 161, a pair of side portions 171 are provided with semicircular recesses 177 extending in the axial direction at positions that are both circumferential ends of the front portion 174, i.e., positions where each side portion 171 and the front portion 174 intersect. Furthermore, the outer surface portion 172 is provided with a pair of protrusions 178 extending in the axial direction at positions that are symmetrical on both sides in the circumferential direction with respect to the center line of the insulating cover 161 in the circumferential direction.

Additional explanation on the recess 177 of the insulating cover 161. As shown in FIG. 20, the first crossover portion 153A of the first partial winding 151A is curved so that it is convex on the radially inner side, i.e., on the side of the core assembly CA. In this configuration, a gap is formed between adjacent first crossover portions 153A in the circumferential direction, and the gap becomes wider toward the tip side of the first crossover portion 153A. Therefore, in this embodiment, the gap between the first crossover portions 153A arranged in the circumferential direction is utilized to provide a recess 177 at a position on the side portion 171 of the insulating cover 161 that is outside the curved portion of the first crossover portion 153A.

The first partial winding 151A may be provided with a temperature detection unit (thermistor). In such a configuration, an opening may be provided in the insulating cover 161 for drawing out a signal line extending from the temperature detection unit. In this case, the temperature detection unit can be conveniently housed within the insulating cover 161.

Although detailed explanation with illustrations is omitted, the other insulating cover 162 in the axial direction has a configuration generally similar to that of the insulating cover 161. Like the insulating cover 161, the insulating cover 162 has a pair of side portions 171, an outer surface portion 172 on the axial outside, an inner surface portion 173 on the axial inside, and a front surface portion 174 on the radial inside. In addition, in the insulating cover 162, the pair of side portions 171 are provided with semicircular recesses 177 at positions that are both circumferential ends of the front surface portion 174, and a pair of protrusions 178 are provided on the outer surface portion 172. The difference from the insulating cover 161 is that the insulating cover 162 does not have an opening for pulling out the winding ends 154, 155 of the first partial winding 151A.

The insulating covers 161 and 162 have different axial height dimensions (i.e., axial width dimensions at the pair of side portions 171 and the front portion 174). Specifically, as shown in FIG. 17, the axial height dimension W11 of the insulating cover 161 and the axial height dimension W12 of the insulating cover 162 are W11>W12. In other words, when winding the conductor CR in multiple layers, it is necessary to switch (change lanes) the winding stages of the conductor CR in a direction perpendicular to the winding direction (circumferential direction), and it is considered that the winding width becomes larger due to the switching. To add, the insulating cover 161 of the insulating covers 161 and 162 is a portion that covers the first crossover portion 153A on the side including the winding start and winding end of the conductor CR, and by including the winding start and winding end of the conductor CR, the winding allowance (overlap allowance) of the conductor CR becomes larger than other portions, which may result in a larger winding width. Taking this into consideration, the axial height dimension W11 of the insulating cover 161 is greater than the axial height dimension W12 of the insulating cover 162. This prevents the insulating covers 161 and 162 from limiting the number of turns of the conductor wire CR, which would occur if the height dimensions W11 and W12 of the insulating covers 161 and 162 were the same.

Next, we will explain the second coil module 150B.

Figure 22(a) is a perspective view showing the configuration of the second coil module 150B, and Figure 22(b) is a perspective view showing the components of the second coil module 150B disassembled. Also, Figure 23 is a cross-sectional view taken along line 23-23 in Figure 22(a).

As shown in Figures 22(a) and (b), the second coil module 150B has a second partial winding 151B that is formed by multiple windings of conductive wire CR, similar to the first partial winding 151A, and insulating covers 163, 164 attached to one and the other axial ends of the second partial winding 151B. The insulating covers 163, 164 are molded from an insulating material such as synthetic resin.

The second partial winding 151B has a pair of intermediate conductor parts 152 arranged parallel to each other and linearly, and a pair of second bridge parts 153B that connect the pair of intermediate conductor parts 152 at both axial ends, and is formed into a ring shape by the pair of intermediate conductor parts 152 and the pair of second bridge parts 153B. In the second partial winding 151B, the pair of intermediate conductor parts 152 has the same configuration as the intermediate conductor part 152 of the first partial winding 151A. In contrast, the pair of second bridge parts 153B has a different configuration from the first bridge part 153A of the first partial winding 151A. The second bridge part 153B of the second partial winding 151B is arranged to extend linearly in the axial direction from the intermediate conductor part 152 without being bent in the radial direction. Figure 18 clearly shows the difference between the partial windings 151A and 151B.

In the second partial winding 151B, an end of the conductor wire CR is pulled out from one of the second crossover parts 153B on both axial sides (the upper second crossover part 153B in FIG. 22(b)), and this end serves as the winding ends 154, 155. As in the first partial winding 151A, in the second partial winding 151B, one of the winding ends 154, 155 is connected to a current input/output terminal, and the other is connected to a neutral point.

In the second partial winding 151B, similar to the first partial winding 151A, each intermediate conductor portion 152 is covered with a sheet-like insulating covering 157. The insulating covering 157 is provided by using a film material FM whose axial dimension is at least the length of the axial insulating covering range of the intermediate conductor portion 152, and wrapping the film material FM around the intermediate conductor portion 152.

The configuration of the insulating cover 157 is also generally the same for each partial winding 151A, 151B. That is, as shown in FIG. 23, the intermediate conductor portion 152 is covered with a film material FM with its circumferential end overlapped. The intermediate conductor portion 152 is provided with an insulating cover 157 so as to cover all of its two circumferential side surfaces and two radial side surfaces. In this case, the insulating cover 157 surrounding the intermediate conductor portion 152 is provided with an overlap portion OL where the film material FM overlaps on a portion facing the intermediate conductor portion 152 in the partial winding 151 of the other phase, i.e., on one of the two circumferential side surfaces of the intermediate conductor portion 152. In this embodiment, the overlap portion OL is provided on the same circumferential side of each of the pair of intermediate conductor portions 152.

In the second partial winding 151B, an insulating cover 157 is provided in the range from the intermediate conductor portion 152 to the portion of the second crossover portion 153B on both axial sides that is covered by the insulating covers 163, 164 (i.e., the portion inside the insulating covers 163, 164). In FIG. 17, the range AX2 in the second coil module 150B is the portion not covered by the insulating covers 163, 164, and the insulating cover 157 is provided in a range extending above and below the range AX2.

In each of the partial windings 151A, 151B, the insulating cover 157 is provided in an area that includes a portion of the transition section 153A, 153B. That is, in each of the partial windings 151A, 151B, the insulating cover 157 is provided on the intermediate conductor section 152 and on the portion of the transition section 153A, 153B that extends linearly beyond the intermediate conductor section 152. However, because the axial lengths of the partial windings 151A, 151B are different, the axial ranges of the insulating cover 157 are also different.

Next, the configuration of the insulating covers 163 and 164 will be described.

The insulating cover 163 is attached to the second crossover portion 153B on one axial side of the second partial winding 151B, and the insulating cover 164 is attached to the second crossover portion 153B on the other axial side of the second partial winding 151B. The configuration of the insulating cover 163 is shown in Figures 24(a) and (b). Figures 24(a) and (b) are perspective views of the insulating cover 163 viewed from two different directions.

24(a) and (b), the insulating cover 163 has a pair of side portions 181 that are circumferential side surfaces, an outer surface portion 182 on the axially outer side, a front surface portion 183 on the radially inner side, and a rear surface portion 184 on the radially outer side. Each of these portions 181 to 184 is formed in a plate shape and is connected to each other in a three-dimensional shape so that only the axially inner side is open. Each of the pair of side portions 181 is provided in a direction that extends toward the axis of the core assembly CA when assembled to the core assembly CA. Therefore, when multiple second coil modules 150B are arranged in a circumferential line, the side portions 181 of the insulating cover 163 of adjacent second coil modules 150B face each other in abutment or close proximity. This allows for a suitable annular arrangement while ensuring mutual insulation between the second coil modules 150B adjacent in the circumferential direction.

In the insulating cover 163, the front surface 183 is provided with an opening 185a for pulling out the winding end 154 of the second partial winding 151B, and the outer surface 182 is provided with an opening 185b for pulling out the winding end 155 of the second partial winding 151B.

The front surface 183 of the insulating cover 163 is provided with a protruding portion 186 that protrudes radially inward. The protruding portion 186 is provided at a position that is the center between one end and the other end of the circumferential direction of the insulating cover 163 so as to protrude radially inward from the second bridge portion 153B. The protruding portion 186 has a tapered shape that tapers radially inward in a plan view, and a through hole 187 extending in the axial direction is provided at its tip. Note that the protruding portion 186 may have any configuration as long as it protrudes radially inward from the second bridge portion 153B and has a through hole 187 at a position that is the center between one end and the other end of the circumferential direction of the insulating cover 163. However, assuming an overlapping state with the insulating cover 161 on the axial inner side, it is desirable to form the protruding portion 186 narrow in the circumferential direction to avoid interference with the winding ends 154, 155.

The protrusion 186 has a stepped axial thickness at its radially inner tip, and a through hole 187 is provided in the thin lower step 186a. This lower step 186a corresponds to a portion where the height from the axial end face of the inner tube member 81 is lower than the height of the second bridge portion 153B when the second coil module 150B is assembled to the core assembly CA.

As shown in FIG. 23, the protrusion 186 is provided with a through hole 188 that penetrates in the axial direction. This makes it possible to fill the gap between the insulating covers 161 and 163 through the through hole 188 when the insulating covers 161 and 163 are overlapped in the axial direction.

Although detailed explanation using the drawings will be omitted, the other insulating cover 164 in the axial direction has a configuration generally similar to that of the insulating cover 163. Like the insulating cover 163, the insulating cover 164 has a pair of side portions 181, an outer surface portion 182 on the axial outside, a front surface portion 183 on the radial inside, and a rear surface portion 184 on the radial outside, and also has a through hole 187 provided at the tip of the protruding portion 186. Also, as a difference from the insulating cover 163, the insulating cover 164 is configured not to have an opening for pulling out the winding ends 154, 155 of the second partial winding 151B.

In the insulating covers 163 and 164, the radial width dimensions of the pair of side portions 181 are different. Specifically, as shown in FIG. 17, the radial width dimension W21 of the side portion 181 of the insulating cover 163 and the radial width dimension W22 of the side portion 181 of the insulating cover 164 are W21>W22. In other words, of the insulating covers 163 and 164, the insulating cover 163 is a portion that covers the second crossover portion 153B on the side including the winding start and winding end of the conductor material CR, and by including the winding start and winding end of the conductor material CR, the winding allowance (overlap allowance) of the conductor material CR is larger than other portions, and as a result, the winding width may become larger. Taking this into consideration, the radial width dimension W21 of the insulating cover 163 is larger than the radial width dimension W22 of the insulating cover 164. This prevents the inconvenience of the insulating covers 163 and 164 limiting the number of turns of the conductor wire CR, unlike when the width dimensions W21 and W22 of the insulating covers 163 and 164 are the same.

Figure 25 is a diagram showing the overlap position of the film material FM when the coil modules 150A, 150B are arranged in the circumferential direction. As described above, in each coil module 150A, 150B, the film material FM is covered around the intermediate conductor portion 152 so as to overlap the portion facing the intermediate conductor portion 152 in the partial winding 151 of the other phase, i.e., the circumferential side surface of the intermediate conductor portion 152 (see Figures 20 and 23). Then, when the coil modules 150A, 150B are arranged in the circumferential direction, the overlap portion OL of the film material FM is arranged on the same side (the right side in the circumferential direction in the figure) of both sides in the circumferential direction. As a result, the overlap portions OL of the film material FM in the intermediate conductor portions 152 of the partial windings 151A, 151B of different phases adjacent to each other in the circumferential direction do not overlap each other in the circumferential direction. In this case, a maximum of three sheets of film material FM overlap between each of the intermediate conductor portions 152 arranged in the circumferential direction.

Next, we will explain the configuration for assembling each coil module 150A, 150B to the core assembly CA.

The coil modules 150A, 150B have different axial lengths and different shapes of the bridge portions 153A, 153B of the partial windings 151A, 151B, and are configured to be attached to the core assembly CA with the first bridge portion 153A of the first coil module 150A facing axially inward and the second bridge portion 153B of the second coil module 150B facing axially outward. As for the insulating covers 161-164, the insulating covers 161, 163 are stacked in the axial direction at one axial end of each coil module 150A, 150B, and the insulating covers 162, 164 are stacked in the axial direction at the other axial end, and each of the insulating covers 161-164 is fixed to the core assembly CA.

Figure 26 is a plan view showing a state where multiple insulating covers 161 are lined up in the circumferential direction when the first coil module 150A is assembled to the core assembly CA, and Figure 27 is a plan view showing a state where multiple insulating covers 161, 163 are lined up in the circumferential direction when the first coil module 150A and the second coil module 150B are assembled to the core assembly CA. Also, Figure 28 (a) is a vertical cross-sectional view showing a state before fixing by the fixing pin 191 in the assembled state of each coil module 150A, 150B to the core assembly CA, and Figure 28 (b) is a vertical cross-sectional view showing a state after fixing by the fixing pin 191 in the assembled state of each coil module 150A, 150B to the core assembly CA.

As shown in FIG. 26, when multiple first coil modules 150A are assembled to the core assembly CA, multiple insulating covers 161 are arranged with their side portions 171 abutting or in close proximity to each other. Each insulating cover 161 is arranged so that the boundary line LB between the opposing side portions 171 coincides with the recess 105 on the axial end surface of the inner tube member 81. In this case, the side portions 171 of the insulating covers 161 adjacent in the circumferential direction abut or come into close proximity to each other, so that the recesses 177 of the insulating covers 161 form through-holes extending in the axial direction, and the positions of the through-holes and the recesses 105 coincide with each other.

As shown in FIG. 27, the second coil module 150B is further assembled to the integral core assembly CA and the first coil module 150A. With this assembly, the multiple insulating covers 163 are arranged with their side portions 181 in contact or close to each other. In this state, the transition portions 153A, 153B are arranged to intersect with each other on the circle on which the intermediate conductor portions 152 are arranged in the circumferential direction. Each insulating cover 163 is arranged such that the protrusion 186 overlaps with the insulating cover 161 in the axial direction and the through hole 187 of the protrusion 186 is axially connected to the through hole portion formed by each recess 177 of the insulating cover 161.

At this time, the protrusion 186 of the insulating cover 163 is guided to a predetermined position by a pair of protrusions 178 provided on the insulating cover 161, so that the position of the through hole 187 on the insulating cover 163 side matches the through hole portion on the insulating cover 161 side and the recess 105 of the inner tube member 81. In other words, when each coil module 150A, 150B is assembled to the core assembly CA, the recess 177 of the insulating cover 161 is located at the back side of the insulating cover 163, so it may be difficult to align the through hole 187 of the protrusion 186 with the recess 177 of the insulating cover 161. In this regard, the protrusion 186 of the insulating cover 163 is guided by the pair of protrusions 178 of the insulating cover 161, making it easier to align the insulating cover 163 with the insulating cover 161.

28(a) and (b), the insulating cover 161 and the protruding portion 186 of the insulating cover 163 are engaged with each other at the overlapping portion, and the fixing pin 191 is fixed as a fixing member. More specifically, the recess 105 of the inner tube member 81, the recess 177 of the insulating cover 161, and the through hole 187 of the insulating cover 163 are aligned, and the fixing pin 191 is inserted into the recesses 105, 177 and the through hole 187. This fixes the insulating covers 161 and 163 to the inner tube member 81 as a unit. According to this configuration, the coil modules 150A and 150B adjacent in the circumferential direction are fixed to the core assembly CA at the coil end CE by a common fixing pin 191. The fixing pin 191 is preferably made of a material with good thermal conductivity, such as a metal pin.

28(b), the fixing pin 191 is attached to the lower step 186a of the protruding portion 186 of the insulating cover 163. In this state, the upper end of the fixing pin 191 protrudes above the lower step 186a, but does not protrude above the upper surface (outer surface 182) of the insulating cover 163. In this case, the fixing pin 191 is longer than the axial height dimension of the overlapping portion between the insulating cover 161 and the protruding portion 186 (lower step 186a) of the insulating cover 163, and has a margin for protruding upward, so that it is considered that the fixing pin 191 can be easily inserted into the recesses 105, 177 and the through hole 187 (i.e., when fixing the fixing pin 191). In addition, because the upper end of the fixing pin 191 does not protrude above the upper surface (outer surface portion 182) of the insulating cover 163, the inconvenience of the axial length of the stator 60 becoming longer due to the fixing pin 191 protruding can be suppressed.

After the insulating covers 161 and 163 are fixed by the fixing pins 191, adhesive is filled through the through holes 188 provided in the insulating cover 163. This allows the insulating covers 161 and 163, which overlap in the axial direction, to be firmly joined to each other. Note that for convenience, the through holes 188 are shown in the range from the top to the bottom of the insulating cover 163 in Figures 28(a) and (b), but in reality, the through holes 188 are provided in a thin plate portion formed by hollowing out or the like.

28(b), the fixing position of each insulating cover 161, 163 by the fixing pin 191 is the axial end face of the stator holder 70 radially inward (left side of the figure) from the stator core 62, and the fixing pin 191 is fixed to the stator holder 70. In other words, the first bridge portion 153A is fixed to the axial end face of the stator holder 70. In this case, since the stator holder 70 is provided with a refrigerant passage 85, the heat generated in the first partial winding 151A is directly transferred from the first bridge portion 153A to the vicinity of the refrigerant passage 85 of the stator holder 70. In addition, the fixing pin 191 is inserted into the recess 105 of the stator holder 70, and the transfer of heat to the stator holder 70 side is promoted through the fixing pin 191. With this configuration, the cooling performance of the stator winding 61 is improved.

In this embodiment, 18 insulating covers 161, 163 are stacked on the inside and outside of the axial direction in the coil end CE, while 18 recesses 105 are provided on the axial end face of the stator holder 70, the same number as the insulating covers 161, 163. The 18 recesses 105 are then fixed by fixing pins 191.

Although not shown, the same is true for the insulating covers 162 and 164 on the opposite axial side. That is, when the first coil module 150A is assembled, the side portions 171 of the insulating covers 162 adjacent in the circumferential direction come into contact with or approach each other, so that the recesses 177 of the insulating covers 162 form through-holes extending in the axial direction, and the positions of the through-holes and the recesses 106 on the axial end surface of the outer tube member 71 are aligned. Then, when the second coil module 150B is assembled, the positions of the through-holes 187 on the insulating cover 164 side are aligned with the through-holes on the insulating cover 163 side and the recesses 106 of the outer tube member 71, and the fixing pins 191 are inserted into the recesses 106, 177, and the through-holes 187, so that the insulating covers 162 and 164 are fixed together with the outer tube member 71.

When assembling each coil module 150A, 150B to the core assembly CA, it is preferable to first attach all the first coil modules 150A to the outer periphery of the core assembly CA, and then assemble all the second coil modules 150B and fix them with the fixing pins 191. Alternatively, it is also possible to first fix two first coil modules 150A and one second coil module 150B to the core assembly CA with one fixing pin 191, and then assemble the first coil modules 150A, assemble the second coil modules 150B, and fix them with the fixing pins 191 repeatedly in this order.

Next, we will explain the busbar module 200.

The busbar module 200 is a winding connection member that is electrically connected to the partial windings 151 of each coil module 150 in the stator winding 61, connects one end of the partial windings 151 of each phase in parallel for each phase, and connects the other end of each partial winding 151 at a neutral point. Figure 29 is a perspective view of the busbar module 200, and Figure 30 is a cross-sectional view showing a portion of the longitudinal section of the busbar module 200.

The busbar module 200 has an annular portion 201, a plurality of connection terminals 202 extending from the annular portion 201, and three input/output terminals 203 provided for each phase winding. The annular portion 201 is formed into an annular shape using an insulating material such as resin.

As shown in FIG. 30, the annular portion 201 has laminated plates 204 that are approximately annular and laminated in multiple layers (five layers in this embodiment) in the axial direction, and four bus bars 211-214 are provided between the laminated plates 204. Each bus bar 211-214 is annular and consists of a U-phase bus bar 211, a V-phase bus bar 212, a W-phase bus bar 213, and a neutral bus bar 214. Each bus bar 211-214 is arranged in the annular portion 201 in the axial direction with the plate surfaces facing each other. Each laminated plate 204 and each bus bar 211-214 are bonded to each other with an adhesive. It is preferable to use an adhesive sheet as the adhesive. However, a liquid or semi-liquid adhesive may be applied. A connection terminal 202 is connected to each of the bus bars 211 to 214 so that it protrudes radially outward from the annular portion 201.

A protrusion 201a extending in a circular shape is provided on the top surface of the annular portion 201, i.e., the top surface of the laminate 204 on the outermost side of the five laminated layers 204.

The busbar module 200 may be one in which the busbars 211-214 are embedded in the annular portion 201, and the busbars 211-214 arranged at predetermined intervals may be integrally insert-molded. The arrangement of the busbars 211-214 is not limited to a configuration in which they are all lined up in the axial direction and all of their plate surfaces face the same direction, but may be a configuration in which they are lined up in the radial direction, a configuration in which they are lined up in two axial rows and two radial rows, a configuration in which the plate surfaces extend in different directions, etc.

29, the connection terminals 202 are arranged in a line in the circumferential direction of the annular portion 201 and extend in the axial direction on the radially outer side. The connection terminals 202 include a connection terminal connected to the U-phase bus bar 211, a connection terminal connected to the V-phase bus bar 212, a connection terminal connected to the W-phase bus bar 213, and a connection terminal connected to the neutral bus bar 214. The connection terminals 202 are provided in the same number as the winding ends 154, 155 of each partial winding 151 in the coil module 150, and each of the connection terminals 202 is connected to one of the winding ends 154, 155 of each partial winding 151. In this way, the bus bar module 200 is connected to the U-phase partial winding 151, the V-phase partial winding 151, and the W-phase partial winding 151, respectively.

The input/output terminals 203 are made of, for example, busbar material, and are provided so as to extend in the axial direction. The input/output terminals 203 include an input/output terminal 203U for the U phase, an input/output terminal 203V for the V phase, and an input/output terminal 203W for the W phase. These input/output terminals 203 are connected to the busbars 211 to 213 for each phase within the annular portion 201. Through these input/output terminals 203, power is input/output from an inverter (not shown) to the phase windings of each phase of the stator winding 61.

The busbar module 200 may be configured to have an integrated current sensor for detecting the phase current of each phase. In this case, the busbar module 200 may be provided with a current detection terminal, and the detection result of the current sensor may be output to a control device (not shown) through the current detection terminal.

In addition, the annular portion 201 has a number of protrusions 205 that protrude toward the inner circumference as fixed portions to the stator holder 70, and the protrusions 205 have through holes 206 that extend in the axial direction.

Figure 31 is a perspective view showing the state in which the busbar module 200 is assembled to the stator holder 70, and Figure 32 is a vertical cross-sectional view of the fixing portion that fixes the busbar module 200. Please refer to Figure 12 for the configuration of the stator holder 70 before the busbar module 200 is assembled.

In FIG. 31, the busbar module 200 is provided on the end plate 91 so as to surround the boss 92 of the inner tube member 81. The busbar module 200 is positioned by assembly to the support 95 (see FIG. 12) of the inner tube member 81, and is then fixed to the stator holder 70 (inner tube member 81) by fastening fasteners 217 such as bolts.

More specifically, as shown in FIG. 32, the end plate portion 91 of the inner tube member 81 is provided with a support portion 95 extending in the axial direction. The busbar module 200 is fixed to the support portion 95 by a fastener 217 with the support portion 95 inserted into the through holes 206 provided in the multiple protrusions 205. In this embodiment, the busbar module 200 is fixed using a retainer plate 220 made of a metal material such as iron. The retainer plate 220 has a fastened portion 222 having an insertion hole 221 through which the fastener 217 is inserted, a pressing portion 223 that presses the upper surface of the annular portion 201 of the busbar module 200, and a bend portion 224 provided between the fastened portion 222 and the pressing portion 223.

When the retainer plate 220 is attached, the fastener 217 is inserted into the insertion hole 221 of the retainer plate 220 and screwed to the support 95 of the inner tube member 81. The pressing portion 223 of the retainer plate 220 is in contact with the upper surface of the annular portion 201 of the busbar module 200. In this case, the retainer plate 220 is pushed downward in the figure as the fastener 217 is screwed into the support 95, and the annular portion 201 is pressed downward by the pressing portion 223 accordingly. The downward pressing force in the figure generated by screwing the fastener 217 is transmitted to the pressing portion 223 through the bend portion 224, so pressing by the pressing portion 223 is performed in a state accompanied by the elastic force of the bend portion 224.

As described above, an annular protrusion 201a is provided on the upper surface of the annular portion 201, and the tip of the retainer plate 220 on the pressing portion 223 side can abut against the protrusion 201a. This prevents the downward pressing force of the retainer plate 220 from escaping radially outward. In other words, the pressing force generated by the screwing of the fastener 217 is properly transmitted to the pressing portion 223 side.

As shown in FIG. 31, when the busbar module 200 is attached to the stator holder 70, the input/output terminals 203 are located 180 degrees circumferentially opposite the inlet opening 86a and the outlet opening 87a that lead to the refrigerant passage 85. However, the input/output terminals 203 and the openings 86a and 87a may be located together in the same position (i.e., in close proximity).

Next, we will explain the relay member 230 that electrically connects the input/output terminal 203 of the busbar module 200 to an external device outside the rotating electric machine 10.

As shown in FIG. 1, in the rotating electric machine 10, the input/output terminals 203 of the busbar module 200 are provided so as to protrude outward from the housing cover 242, and are connected to the relay member 230 on the outside of the housing cover 242. The relay member 230 is a member that relays the connection between the input/output terminals 203 for each phase extending from the busbar module 200 and the power lines for each phase extending from an external device such as an inverter.

Figure 33 is a vertical cross-sectional view showing the state in which relay member 230 is attached to housing cover 242, and Figure 34 is a perspective view of relay member 230. As shown in Figure 33, a through hole 242a is formed in housing cover 242, and input/output terminal 203 can be pulled out through this through hole 242a.

The relay member 230 has a main body 231 fixed to the housing cover 242, and a terminal insertion portion 232 inserted into the through hole 242a of the housing cover 242. The terminal insertion portion 232 has three insertion holes 233 through which the input/output terminals 203 of each phase are inserted one by one. The three insertion holes 233 have an elongated cross-sectional opening, and are aligned so that the longitudinal directions of the three insertion holes 233 are all oriented in approximately the same direction.

Three relay bus bars 234, one for each phase, are attached to the main body 231. The relay bus bars 234 are bent into a roughly L-shape and are fixed to the main body 231 with fasteners 235 such as bolts, and are fixed to the tip of the input/output terminal 203 inserted into the insertion hole 233 of the terminal insertion portion 232 with fasteners 236 such as bolts and nuts.

Although not shown in the figure, the relay member 230 can be connected to a power line for each phase extending from an external device, making it possible to input and output power to the input/output terminal 203 for each phase.

Next, the configuration of the control system that controls the rotating electric machine 10 will be described. Figure 35 is an electrical circuit diagram of the control system for the rotating electric machine 10, and Figure 36 is a functional block diagram showing the control process by the control device 270.

As shown in FIG. 35, the stator winding 61 is composed of a U-phase winding, a V-phase winding, and a W-phase winding, and an inverter 260 equivalent to a power converter is connected to the stator winding 61. The inverter 260 is configured as a full bridge circuit having the same number of upper and lower arms as the number of phases, and a series connection consisting of an upper arm switch 261 and a lower arm switch 262 is provided for each phase. Each of these switches 261, 262 is turned on and off by a driver 263, and the phase winding of each phase is energized by the on and off. Each of the switches 261, 262 is configured of a semiconductor switching element such as a MOSFET or an IGBT. In addition, a charge supply capacitor 264 for supplying the charge required during switching to each switch 261, 262 is connected in parallel to the series connection of the switches 261, 262 to the upper and lower arms of each phase.

One end of the U-phase winding, the V-phase winding, and the W-phase winding are connected to the intermediate connection point between the switches 261 and 262 of the upper and lower arms. These phase windings are star-connected (Y-connected), and the other ends of the phase windings are connected to each other at the neutral point.

The control device 270 is equipped with a microcomputer consisting of a CPU and various memories, and performs current control by turning on and off each switch 261, 262 based on various detection information in the rotating electric machine 10 and requests for power running and power generation. The detection information of the rotating electric machine 10 includes, for example, the rotation angle (electrical angle information) of the rotor 20 detected by an angle detector such as a resolver, the power supply voltage (inverter input voltage) detected by a voltage sensor, and the current of each phase detected by a current sensor. The control device 270 performs on/off control of each switch 261, 262, for example, by PWM control at a predetermined switching frequency (carrier frequency) or square wave control. The control device 270 may be an internal control device built into the rotating electric machine 10, or an external control device provided outside the rotating electric machine 10.

Incidentally, since the rotating electric machine 10 of this embodiment has a slotless structure (teethless structure), the inductance of the stator 60 is reduced and the electrical time constant is small. In a situation where the electrical time constant is small, it is desirable to increase the switching frequency (carrier frequency) and the switching speed. In this regard, the charge supply capacitor 264 is connected in parallel to the series connection of the switches 261, 262 of each phase, thereby reducing the wiring inductance, and appropriate surge countermeasures are possible even in a configuration with a high switching speed.

The high-potential terminal of the inverter 260 is connected to the positive terminal of the DC power supply 265, and the low-potential terminal is connected to the negative terminal (ground) of the DC power supply 265. The DC power supply 265 is formed, for example, from a battery pack in which multiple single cells are connected in series. In addition, a smoothing capacitor 266 is connected in parallel to the DC power supply 265 to the high-potential terminal and low-potential terminal of the inverter 260.

Figure 36 is a block diagram showing the current feedback control process that controls the currents of the U, V, and W phases.

In FIG. 36, the current command value setting unit 271 uses a torque-dq map to set a d-axis current command value and a q-axis current command value based on the powering torque command value or the power generation torque command value for the rotating electric machine 10, and the electrical angular velocity ω obtained by time-differentiating the electrical angle θ. Note that the power generation torque command value is a regenerative torque command value, for example, when the rotating electric machine 10 is used as a power source for a vehicle.

The dq converter 272 converts the current detection values (three phase currents) from the current sensors provided for each phase into d-axis current and q-axis current, which are components of an orthogonal two-dimensional rotating coordinate system in which the d-axis is the direction of an axis of a magnetic field, or field direction.

The d-axis current feedback control unit 273 calculates a d-axis command voltage as an operation amount for feedback-controlling the d-axis current to the d-axis current command value. The q-axis current feedback control unit 274 calculates a q-axis command voltage as an operation amount for feedback-controlling the q-axis current to the q-axis current command value. In each of these feedback control units 273, 274, the command voltage is calculated using a PI feedback method based on the deviation of the d-axis current and the q-axis current from the current command value.

The three-phase conversion unit 275 converts the d-axis and q-axis command voltages into U-phase, V-phase, and W-phase command voltages. Each of the above units 271 to 275 is a feedback control unit that performs feedback control of the fundamental wave current according to the dq conversion theory, and the U-phase, V-phase, and W-phase command voltages are the feedback control values.

The operation signal generating unit 276 generates an operation signal for the inverter 260 based on the three-phase command voltages using a well-known triangular wave carrier comparison method. Specifically, the operation signal generating unit 276 generates switch operation signals (duty signals) for the upper and lower arms in each phase by PWM control based on a magnitude comparison between a signal in which the three-phase command voltages are normalized by the power supply voltage and a carrier signal such as a triangular wave signal. The switch operation signals generated by the operation signal generating unit 276 are output to the driver 263 of the inverter 260, and the driver 263 turns on and off the switches 261 and 262 of each phase.

Next, the torque feedback control process will be described. This process is mainly used for the purpose of increasing the output of the rotating electric machine 10 and reducing losses under operating conditions where the output voltage of the inverter 260 is high, such as in the high rotation range and high output range. The control device 270 selects and executes either the torque feedback control process or the current feedback control process based on the operating conditions of the rotating electric machine 10.

Figure 37 is a block diagram showing the torque feedback control process for the U, V, and W phases.

The voltage amplitude calculation unit 281 calculates a voltage amplitude command, which is a command value for the magnitude of a voltage vector, based on a powering torque command value or a power generation torque command value for the rotating electric machine 10 and the electrical angular velocity ω obtained by time-differentiating the electrical angle θ.

The dq conversion unit 282 converts the current detection values from the current sensors provided for each phase into d-axis current and q-axis current, similar to the dq conversion unit 272. The torque estimation unit 283 calculates the torque estimation values corresponding to the U, V, and W phases based on the d-axis current and the q-axis current. The torque estimation unit 283 calculates the voltage amplitude command based on map information that correlates the d-axis current, the q-axis current, and the voltage amplitude command.

The torque feedback control unit 284 calculates a voltage phase command, which is a command value for the phase of the voltage vector, as an operation amount for feedback control of the torque estimate value to the powering torque command value or the power generation torque command value. The torque feedback control unit 284 calculates the voltage phase command using a PI feedback method based on the deviation of the torque estimate value from the powering torque command value or the power generation torque command value.

The operation signal generating unit 285 generates an operation signal for the inverter 260 based on the voltage amplitude command, the voltage phase command, and the electrical angle θ. Specifically, the operation signal generating unit 285 calculates three-phase command voltages based on the voltage amplitude command, the voltage phase command, and the electrical angle θ, and generates switch operation signals for the upper and lower arms in each phase by PWM control based on a comparison of the magnitude between a signal obtained by normalizing the calculated three-phase command voltages with the power supply voltage and a carrier signal such as a triangular wave signal. The switch operation signals generated by the operation signal generating unit 285 are output to the driver 263 of the inverter 260, and the driver 263 turns on and off the switches 261 and 262 of each phase.

Incidentally, the operation signal generating unit 285 may generate a switch operation signal based on pulse pattern information, which is map information in which a voltage amplitude command, a voltage phase command, an electrical angle θ, and a switch operation signal are associated, a voltage amplitude command, a voltage phase command, and an electrical angle θ.

(Modification)
Modifications of the first embodiment will now be described.

- The configuration of the magnet 32 in the magnet unit 22 may be changed as follows. In the magnet unit 22 shown in FIG. 38, the magnetization easy axis of the magnet 32 is inclined to the radial direction, and a linear magnetic flux path is formed along the direction of the magnetization easy axis. In other words, the magnet 32 is configured so that the direction of the magnetization easy axis is inclined to the d-axis between the magnetic flux action surface 34a on the stator 60 side (radially inner side) and the magnetic flux action surface 34b on the opposite stator side (radially outer side), and is linearly oriented so that it approaches the d-axis on the stator 60 side in the circumferential direction and moves away from the d-axis on the opposite stator side. Even in this configuration, the magnetic flux path length of the magnet 32 can be made longer than the radial thickness dimension, making it possible to improve permeance.

- It is also possible to use Halbach array magnets in the magnet unit 22.

- In each partial winding 151, the bending direction of the crossover portion 153 may be either radially inward or outward, and in terms of its relationship with the core assembly CA, the first crossover portion 153A may be bent toward the core assembly CA, or the first crossover portion 153A may be bent toward the opposite side of the core assembly CA. In addition, the second crossover portion 153B may be bent either radially inward or outward, as long as it is axially outside the first crossover portion 153A and circumferentially spans a portion of the first crossover portion 153A.

・The partial winding 151 may have only one type of partial winding 151, instead of two types of partial winding 151 (first partial winding 151A, second partial winding 151B). Specifically, the partial winding 151 may be formed to have an approximately L-shape or an approximately Z-shape in side view. When the partial winding 151 is formed to have an approximately L-shape in side view, the crossover portion 153 is bent radially inward or outward at one axial end, and the crossover portion 153 is not bent radially at the other axial end. When the partial winding 151 is formed to have an approximately Z-shape in side view, the crossover portion 153 is bent radially in opposite directions at one axial end and the other axial end. In either case, the coil module 150 may be fixed to the core assembly CA by an insulating cover that covers the crossover portion 153 as described above.

- In the above configuration, all partial windings 151 for each phase winding in the stator winding 61 are connected in parallel, but this may be changed. For example, all partial windings 151 for each phase winding may be divided into multiple parallel connection groups, and the multiple parallel connection groups may be connected in series. In other words, all n partial windings 151 in each phase winding may be divided into two parallel connection groups of n/2 pieces each, or three parallel connection groups of n/3 pieces each, and these may be connected in series. Alternatively, all multiple partial windings 151 for each phase winding in the stator winding 61 may be connected in series.

The stator winding 61 in the rotating electric machine 10 may be configured to have two-phase windings (a U-phase winding and a V-phase winding). In this case, for example, in the partial winding 151, a pair of intermediate conductor portions 152 are provided one coil pitch apart, and one intermediate conductor portion 152 in the partial winding 151 of the other phase is disposed between the pair of intermediate conductor portions 152.

-Instead of the outer rotor type surface magnet type rotating electric machine 10, it is also possible to embody it as an inner rotor type surface magnet type rotating electric machine. Figures 39(a) and (b) are diagrams showing the configuration of the stator unit 300 when an inner rotor structure is used. Of these, Figure 39(a) is a perspective view showing the state in which the coil modules 310A, 310B are assembled to the core assembly CA, and Figure 39(b) is a perspective view showing the partial windings 311A, 311B included in each coil module 310A, 310B. In this example, the core assembly CA is formed by assembling the stator holder 70 to the radial outside of the stator core 62. In addition, multiple coil modules 310A, 310B are assembled to the radial inside of the stator core 62.

The partial winding 311A has a configuration similar to that of the first partial winding 151A described above, and includes a pair of intermediate conductor portions 312 and a bridge portion 313A that is bent toward the core assembly CA side (radially outward) on both axial sides. The partial winding 311B has a configuration similar to that of the second partial winding 151B described above, and includes a pair of intermediate conductor portions 312 and a bridge portion 313B that is provided on both axial sides so as to straddle the bridge portion 313A circumferentially on the axially outer side. An insulating cover 315 is attached to the bridge portion 313A of the partial winding 311A, and an insulating cover 316 is attached to the bridge portion 313B of the partial winding 311B.

The insulating cover 315 has semicircular recesses 317 extending in the axial direction on both circumferential side surfaces. The insulating cover 316 has a protruding portion 318 that protrudes radially outward beyond the bridge portion 313B, and a through hole 319 extending in the axial direction is provided at the tip of the protruding portion 318.

Figure 40 is a plan view showing the state in which coil modules 310A, 310B are assembled to core assembly CA. In addition, in Figure 40, multiple recesses 105 are formed at equal intervals in the circumferential direction on the axial end face of stator holder 70. In addition, stator holder 70 has a cooling structure that uses liquid refrigerant or air, and for example, as an air-cooled structure, multiple heat dissipation fins may be formed on the outer circumferential surface.

In FIG. 40, the insulating covers 315 and 316 are arranged so that they overlap in the axial direction. In addition, a recess 317 provided on the side of the insulating cover 315 and a through hole 319 provided in the protruding portion 318 of the insulating cover 316 at a position that is central between one end and the other end of the circumference of the insulating cover 316 are connected in the axial direction, and each of these portions is fixed by a fixing pin 321.

In addition, in FIG. 40, the fixing position of each insulating cover 315, 316 by the fixing pin 321 is the axial end face of the stator holder 70 radially outward of the stator core 62, and the fixing pin 321 is fixed to the stator holder 70. In this case, since the stator holder 70 is provided with a cooling structure, heat generated in the partial windings 311A, 311B is easily transferred to the stator holder 70. This improves the cooling performance of the stator winding 61.

The stator 60 used in the rotating electric machine 10 may have protrusions (e.g., teeth) extending from the back yoke. In this case, it is sufficient that the coil module 150 and the like are attached to the stator core by the back yoke.

- Rotating electric machines are not limited to star-connected ones, and can also be delta-connected ones.

-As the rotating electric machine 10, instead of a rotating field type rotating electric machine in which the field element is the rotor and the armature is the stator, it is also possible to adopt a rotating armature type rotating electric machine in which the armature is the rotor and the field element is the stator.

Second Embodiment
Next, a rotating electric machine 400 in a second embodiment will be described. The rotating electric machine 400 in this embodiment is used as an in-wheel motor of a vehicle. An outline of the rotating electric machine 400 is shown in Figs. 41 to 46. Fig. 41 is a perspective view showing the entire rotating electric machine 400, Fig. 42 is a plan view of the rotating electric machine 400, Fig. 43 is a vertical cross-sectional view of the rotating electric machine 400 (cross-sectional view taken along line 43-43 in Fig. 42), Fig. 44 is a horizontal cross-sectional view of the rotating electric machine 400 (cross-sectional view taken along line 44-44 in Fig. 43), Fig. 45 is a horizontal cross-sectional view of the rotating electric machine 400 (cross-sectional view taken along line 45-45 in Fig. 43), and Fig. 46 is an exploded cross-sectional view showing the components of the rotating electric machine 400 in an exploded manner.

The rotating electric machine 400 is an outer rotor type surface magnet type rotating electric machine. The rotating electric machine 400 is roughly divided into a rotating electric machine main body having a rotor 410 and a stator unit 420 including a stator 430, and a spindle 401 fixed to a vehicle body (not shown) and a hub 402 fixed to a wheel (not shown) are integrated with the rotating electric machine main body. The spindle 401 and the hub 402 are required to have high strength and are made of, for example, steel material.

The spindle 401 has a flange portion 403 extending perpendicular to the axial direction, and a fixed shaft portion 404 that is cylindrical and extends toward the center of the rotating electric machine from the flange portion 403, and is inserted into the hollow portion of the stator unit 420. The fixed shaft portion 404 may have a large diameter portion and a small diameter portion as shown in the figure. The hub 402 has an insertion hole 406 through which the fixed shaft portion 404 is inserted. Then, with the fixed shaft portion 404 inserted into the insertion hole 406 of the hub 402, the hub 402 is rotatably supported by a pair of bearings 407, 408. The hub 402 is rotatably supported by the bearings 407, 408 at two positions in the axial direction. The bearings 407, 408 are, for example, radial ball bearings, and each has an outer ring, an inner ring, and a plurality of balls arranged between the outer ring and the inner ring. Bearings 407 and 408 may be roller bearings (needle roller bearings, tapered roller bearings) that use rollers instead of balls as rolling elements.

The rotating electric machine 400 is attached to the vehicle with the axial direction of the axis of rotation (left and right direction in FIG. 43) being horizontal or nearly horizontal. If the wheels have a camber angle, it is preferable that the axial direction of the rotating electric machine 400 be nearly horizontal with a tilt of the camber angle.

In the rotating electric machine 400, the rotor 410 and the stator 430 are arranged radially opposite each other with an air gap between them. The stator unit 420 is fixed to the spindle 401, and the rotor 410 is fixed to the hub 402. Therefore, the hub 402 and the rotor 410 are rotatable relative to the spindle 401 and the stator unit 420.

As shown in FIG. 46, the rotor 410 has a substantially cylindrical rotor carrier 411 and an annular magnet unit 412 fixed to the rotor carrier 411. The rotor carrier 411 has a cylindrical tubular portion 413 and an end plate portion 414 provided on one axial end side of the tubular portion 413, and the magnet unit 412 is fixed in an annular shape to the radial inside of the tubular portion 413. The other axial end side of the rotor carrier 411 is open. The rotor carrier 411 functions as a magnet holding member. A through hole 414a is formed in the center of the end plate portion 414, and the hub 402 is fixed to the end plate portion 414 by a fastener such as a bolt while being inserted into the through hole 414a (see FIG. 43).

The magnet unit 412 is composed of multiple permanent magnets arranged so that the polarity alternates along the circumferential direction of the rotor 410. The magnet unit 412 corresponds to the "magnet section." As a result, the magnet unit 412 has multiple magnetic poles in the circumferential direction. The magnet unit 412 has the configuration described as the magnet unit 22 in Figures 6 and 7 of the first embodiment, for example, and is composed of sintered neodymium magnets as permanent magnets, with an intrinsic coercive force of 400 [kA/m] or more and a residual magnetic flux density Br of 1.0 [T] or more.

Magnet unit 412, like magnet unit 22 in FIG. 7, has multiple permanent magnets, each with polar anisotropy, and the orientation of the magnetization easy axis of each magnet differs between the d-axis side (part closer to the d-axis) and the q-axis side (part closer to the q-axis), with the magnetization easy axis oriented parallel to the d-axis on the d-axis side and perpendicular to the q-axis on the q-axis side. In this case, an arc-shaped magnetic flux path is formed along the orientation of the magnetization easy axis. In short, each magnet is configured so that the magnetization easy axis is oriented more parallel to the d-axis on the d-axis side, which is the magnetic pole center, than on the q-axis side, which is the magnetic pole boundary.

The magnets of the magnet unit 412 may be fixed to each other in the circumferential direction by adhesive or the like, and may be integrated by attaching a fixing member such as yarn to the outer periphery. Also, an annular end plate member may be attached to the axial end of each magnet.

Next, the configuration of the stator unit 420 will be described. Figure 47 is an exploded perspective view of the stator unit 420. The stator unit 420 has a circular cylindrical stator 430, a stator holder 460 that holds the stator 430, a wiring module 480 that is attached to one axial end, and a coil end cover 490 that is attached to the other axial end of the stator 430.

First, the stator 430 will be described. Figures 48 and 49 are exploded perspective views of the stator 430, showing the stator winding 431 and the stator core 432 separated from each other, and Figure 50 is an exploded cross-sectional view of the stator unit 420, showing the stator 430, the stator holder 460, and the coil end cover 490 separated from each other. Figures 48 and 49 are exploded perspective views of the stator 430, seen from different axial directions.

The stator 430 is an armature with a teethless structure, and has a stator winding 431 and a stator core 432. In the stator 430, the stator winding 431 has three phase windings, and each phase winding is composed of multiple partial windings 441. The partial windings 441 are provided according to the number of poles of the rotating electric machine 400, and multiple partial windings 441 are connected in parallel or series for each phase. In this embodiment, the number of magnetic poles is 24, but the number is arbitrary.

As shown in FIG. 50, the stator 430 has, in the axial direction, a portion corresponding to the coil side CS that faces the stator core 432 in the radial direction, and a portion corresponding to the coil end CE that is axially outside the coil side CS. The coil side CS is also a portion that faces the magnet unit 412 of the rotor 410 in the radial direction. The partial winding 441 is assembled to the radial outside of the stator core 432. In this case, the partial winding 441 is assembled with both axial end portions protruding axially outward (i.e., toward the coil end CE) beyond the stator core 432.

Each of the partial windings 441 is provided with one of its axial ends bent radially and the other not bent radially. Half of all the partial windings 441 have one axial end (lower side of FIG. 48) bent and bent radially inward at that bent side. The remaining half of the partial windings 441 have the other axial end (upper side of FIG. 48) bent and bent radially outward at that bent side. In the following description, the partial winding 441 with a bent portion bent radially inward is also referred to as "partial winding 441A" and the partial winding 441 with a bent portion bent radially outward is also referred to as "partial winding 441B".

The configuration of the partial windings 441A and 441B will be described in detail. Figures 51(a) and (b) are perspective views showing the configuration of the partial winding 441A, and Figure 52 is an exploded perspective view showing the insulating covers 451 and 452 attached to the crossover parts 443 and 444 in the partial winding 441A. Figures 53(a) and (b) are perspective views showing the configuration of the partial winding 441B, and Figure 54 is an exploded perspective view showing the insulating covers 453 and 454 attached to the crossover parts 443 and 444 in the partial winding 441B. Figures 51(a) and (b) are perspective views of the partial winding 441A as viewed from the radial inside and outside, respectively, and Figures 53(a) and (b) are similarly perspective views of the partial winding 441B as viewed from the radial inside and outside, respectively.

Each of the partial windings 441A and 441B is constructed by winding a conductor material in multiple layers, and has a pair of intermediate conductor parts 442 that are parallel to each other and arranged in a straight line, and a pair of bridge parts 443, 444 that connect the pair of intermediate conductor parts 442 at both axial ends. The pair of intermediate conductor parts 442 and the pair of bridge parts 443, 444 form a ring shape. The pair of intermediate conductor parts 442 are arranged at a predetermined coil pitch apart, and the intermediate conductor part 442 of the partial winding 441 of the other phase can be arranged between the pair of intermediate conductor parts 442 in the circumferential direction. In this embodiment, the pair of intermediate conductor parts 442 are arranged at a distance of two coil pitches, and one intermediate conductor part 442 in the partial winding 441 of the other two phases is arranged between the pair of intermediate conductor parts 442. When the partial windings 441A, 441B are arranged side by side in the circumferential direction, the intermediate conductor portions 442 of the different partial windings 441A, 441B are arranged side by side in the circumferential direction in close proximity to each other.

In the partial windings 441A and 441B, each intermediate conductor portion 442 is provided covered with a sheet-like insulating cover 445. The configuration of the insulating cover 445 is the same as that of the insulating cover 157 of the partial winding 151 in the first embodiment described above. That is, the insulating cover 445 is provided by using a film material having an axial dimension at least the length of the axial insulating cover range of the intermediate conductor portion 442, and winding the film material around the intermediate conductor portion 442. The insulating cover 445 is provided around the intermediate conductor portion 442 with the circumferential end of the film material overlapping.

The crossover parts 443, 444 on both sides in the axial direction are provided as parts corresponding to the coil end CE (see FIG. 50). Of the crossover parts 443, 444, one crossover part 443 is bent in the radial direction, while the other crossover part 444 is not bent in the radial direction. As a result, the partial windings 441A, 441B are approximately L-shaped when viewed from the side.

The partial windings 441A and 441B have different radial bending directions of the jumper portion 443, with the jumper portion 443 of the partial winding 441A being bent radially inward, and the jumper portion 443 of the partial winding 441B being bent radially outward. In this case, assuming that the partial windings 441A and 441B are arranged side by side in the circumferential direction, it is preferable that the shapes in plan view (radial plan shapes) of the jumper portions 443 of the partial windings 441A and 441B are different from each other, and the jumper portion 443 of the partial winding 441A has a narrower circumferential width toward the tip, and the jumper portion 443 of the partial winding 441B has a wider circumferential width toward the tip.

In each partial winding 441A, 441B, the intermediate conductor portions 442 are provided as coil side conductor portions arranged one by one in the circumferential direction on the coil side CS. In addition, each transition portion 443, 444 is provided as a coil end conductor portion that connects intermediate conductor portions 442 of the same phase at two different positions in the circumferential direction on the coil end CE.

In the partial windings 441A and 441B, similar to the partial winding 151 described above, the conductor wire material is wound multiple times so that the cross section of the conductor wire assembly portion is rectangular. In the case of the intermediate conductor portion 442, the conductor wire material is arranged in multiple rows in the circumferential direction and multiple rows in the radial direction, so that the cross section is formed into a substantially rectangular shape (see FIG. 20).

Next, the insulating covers 451 to 454 attached to each partial winding 441A, 441B will be described. The insulating covers 451 to 454 are insulating members provided to insulate the partial windings 441 from each other at each transition portion 443, 444. The insulating covers 451 to 454 are molded from an insulating material such as synthetic resin.

As shown in Figs. 51(a), (b) and 52, in the partial winding 441A, an insulating cover 451 is attached to the bridge portion 443 at one axial end, and an insulating cover 452 is attached to the bridge portion 444 at the other axial end. A bracket 455 made of, for example, a metal plate is embedded in the insulating cover 451. The bracket 455 has a protruding portion 455a protruding radially outward from the tip of the bridge portion 443, and the protruding portion 455a is provided with a through hole 455b penetrating in the axial direction (vertical direction in the figure). In addition, a bracket 456 made of, for example, a metal plate is embedded in the insulating cover 452. The bracket 456 has a protruding portion 456a protruding radially outward from the tip of the bridge portion 444, and the protruding portion 456a is provided with a through hole 456b penetrating in the axial direction (vertical direction in the figure).

The insulating covers 451, 452 each have an engagement portion 451a, 452a that engages with the inside of the curved portion at the tip of the bridge portion 443, 444 of the partial winding 441A. It is preferable that a part of the bracket 455, 456 is integrated with these engagement portions 451a, 452a as a base material. In addition to being embedded in the insulating covers 451, 452, the bracket 455, 456 may be fixed to the outer surface of the insulating covers 451, 452 by adhesive or the like.

As shown in Figs. 53(a), (b) and 54, in the partial winding 441B, an insulating cover 453 is attached to the bridge portion 443 at one axial end, and an insulating cover 454 is attached to the bridge portion 444 at the other axial end. A bracket 457 made of, for example, a metal plate is embedded in the insulating cover 453. The bracket 457 has a protruding portion 457a protruding radially inward from the tip of the bridge portion 443, and the protruding portion 457a has a through hole 457b penetrating in the axial direction (vertical direction in the figure). A bracket 458 made of, for example, a metal plate is embedded in the insulating cover 454. The bracket 458 has a protruding portion 458a protruding radially inward from the tip of the bridge portion 444, and the protruding portion 458a has a through hole 458b penetrating in the axial direction (vertical direction in the figure).

The insulating covers 453, 454 each have an engagement portion 453a, 454a that engages with the inside of the curved portion at the tip of the bridge portion 443, 444 of the partial winding 441B. It is preferable that a part of the brackets 457, 458 is integrated with these engagement portions 453a, 454a as a base material. In addition to being embedded in the insulating covers 453, 454, the brackets 457, 458 may be fixed to the outer surface of the insulating covers 453, 454 by adhesive or the like.

Figure 55 is a plan view showing the partial windings 441A, 441B arranged side by side in the circumferential direction. Note that Figure 55 is a plan view of the stator winding 431 shown in Figure 48 as seen from one axial direction (from above in the figure).

In FIG. 55, the crossover portion 443 of the partial winding 441A extends radially inward, and the crossover portion 443 of the partial winding 441B extends radially outward. Radially inward of the intermediate conductor portion 442 of each partial winding 441A, 441B, at one axial end side of the stator winding 431 (the back side of the page in FIG. 55), the protrusion 455a of the bracket 455 provided on the insulating cover 451 of the partial winding 441A and the protrusion 458a of the bracket 458 provided on the insulating cover 454 of the partial winding 441B overlap in the axial direction, and the positions of the through holes 455b, 458b of each protrusion 455a, 458a match in a plan view.

In addition, radially outward of the intermediate conductor portion 442 of each partial winding 441A, 441B, at the other axial end side of the stator winding 431 (the front side of the paper in FIG. 55), the protrusions 456a of the bracket 456 provided on the insulating cover 452 of the partial winding 441A and the protrusions 457a of the bracket 457 provided on the insulating cover 453 of the partial winding 441B are arranged alternately and at equal intervals in the circumferential direction. In this case, the through holes 456b, 457b of each protrusion 456a, 457a are arranged at the same radial distance from the center of the plane of the stator 430 and are arranged at equal intervals in the circumferential direction.

As shown in Figures 48 and 49, the stator winding 431 is formed into a ring shape by arranging partial windings 441A, 441B in the circumferential direction, and the stator core 432 is arranged radially inside the ring. The stator core 432 is configured as a core sheet laminate in which core sheets made of magnetic electromagnetic steel plates are stacked in the axial direction, and has a cylindrical shape with a predetermined thickness in the radial direction. The inner and outer circumferential surfaces of the stator core 432 are curved surfaces with no irregularities. The stator core 432 functions as a back yoke.

In this embodiment, the stator core 432 is divided into multiple parts in the circumferential direction, and the cylindrical stator core 432 is formed by multiple divided cores 435 arranged in the circumferential direction. The divided cores 435 are provided to individually correspond to the partial winding 441A of the partial windings 441A, 441B, and the number of divided cores 435 is the same as that of the partial winding 441A, and the circumferential width dimension of the divided cores 435 is the same as that of the partial winding 441A. In addition, the axial width dimension of the divided cores 435 is the same as the axial width dimension of the magnet unit 412 (permanent magnet) of the rotor 410.

The split core 435 is a core sheet laminate in which many core sheets are stacked, and is formed by stacking the core sheets using a molding frame, for example. However, it is also possible to stack multiple core sheets punched into annular plates in the axial direction to form a cylinder, and then cut the cylinder into multiple pieces in the circumferential direction to form multiple split cores 435. It is also possible to stack a long core sheet while winding it in a ring shape to form a cylinder with a helical core structure, and then cut the cylinder into multiple pieces in the circumferential direction to form multiple split cores 435. Other detailed configurations of the split core 435 will be described later.

Next, the configuration of the stator holder 460 will be described. Here, the configuration of the stator holder 460 will be described using Figures 50 and 56. Figure 56 is a cross-sectional view of the stator holder 460 (cross-sectional view at the same position as Figure 45).

As shown in Figures 50 and 56, the stator holder 460 has an outer cylinder member 461 and an inner cylinder member 462, each of which is cylindrical, and is constructed by assembling them together, with the outer cylinder member 461 on the radial outside and the inner cylinder member 462 on the radial inside. Each of these members 461, 462 is constructed of metal, such as aluminum or cast iron, or carbon fiber reinforced plastic (CFRP).

The inner diameter of the cylindrical portion of the outer cylinder member 461 is larger than the outer diameter of the cylindrical portion of the inner cylinder member 462. Therefore, when the inner cylinder member 462 is assembled to the radial inside of the outer cylinder member 461, an annular gap is formed between these members 461, 462, and the gap space serves as a refrigerant passage 463 through which a refrigerant such as cooling water flows. The refrigerant passage 463 is provided in an annular shape in the circumferential direction of the stator holder 460. The inner cylinder member 462 is provided with an inlet side passage 464 which serves as an inlet for the refrigerant and an outlet side passage 465 which serves as an outlet for the refrigerant, and a partition portion 466 is provided between the inlet side passage 464 and the outlet side passage 465 in the refrigerant passage 463. The inlet side passage 464 and the outlet side passage 465 are connected to the refrigerant passage 463 on both sides of the partition portion 466, and are provided to extend in the axial direction. The refrigerant flowing in from the inlet passage 464 flows circumferentially through the refrigerant passage 463 and then flows out from the outlet passage 465.

One end of the inlet side passage 464 and one end of the outlet side passage 465 each open to the axial end face of the inner cylinder member 462. At the axial end face, an inlet piping port 467 is provided at the opening of the inlet side passage 464, and an outlet piping port 468 is provided at the opening of the outlet side passage 465 (see FIG. 42).

Although not shown, a circulation path for circulating the refrigerant is connected to the inlet piping port 467 and the outlet piping port 468. The circulation path is provided with, for example, an electric pump and a heat dissipation device such as a radiator, and the refrigerant circulates through the circulation path and the refrigerant passage 463 of the rotating electric machine 400 as the pump is driven.

The inner cylinder member 462 is cylindrical and has an end plate portion 471 at one axial end. A through hole 472 is provided in the center of the end plate portion 471, which passes through in the axial direction, and the fixed shaft portion 404 of the spindle 401 can be inserted into the through hole 472.

In addition, a number of protrusions 473 are provided at a predetermined interval in the circumferential direction on the inner periphery side of the inner tube member 462. Each of these protrusions 473 is provided so as to protrude radially inward in the hollow portion of the inner tube member 462, and is provided in the axial range from the end plate portion 471 to the axial middle position (see FIG. 50). The protrusions 473 function as reinforcing members for the inner tube member 462.

The end plate portion 471 of the inner tube member 462 has an opening 474 that penetrates in the axial direction at a position radially outside the through hole 472. This opening 474 is an insertion hole portion through which the power lines 485 of each phase described below are inserted in the axial direction. A terminal block 475 is provided in the opening 474 (see FIG. 41), and external wiring (not shown) is connected to the terminal block 475.

As shown in FIG. 56, the end plate portion 471 of the inner tube member 462 is provided with an insertion hole 476 that penetrates in the axial direction at a position radially outside the through hole 472 and at a position where at least one protrusion 473 is interposed between the end plate portion 471 and the opening 474 in the circumferential direction. This insertion hole 476 is a hole portion through which a resolver signal line 522, which will be described later, is inserted in the axial direction.

Here, the multiple split cores 435 that make up the stator core 432 will be described in detail, showing their relationship to the partial windings 441A, 441B and the stator holder 460. Figure 57 is an enlarged cross-sectional view showing the split cores 435 and partial windings 441A, 441B assembled to the stator holder 460, and Figure 58 is a perspective view showing the partial winding 441A and the split cores 435 integrated together.

The split core 435 has a cross section formed in an arc shape to match the curved surface on the outer periphery of the stator holder 460, with the radially inner side being a concave curved surface and the radially outer side being a convex curved surface. The split core 435 is positioned relative to the stator holder 460 by engagement of the concave and convex surfaces of the opposing surfaces, and a convex portion 436 is provided on the radially inner surface of the split core 435, while a concave portion 477 is provided on the outer periphery of the outer tube member 461 of the stator holder 460. The convex portion 436 on the split core 435 side and the concave portion 477 on the stator holder 460 side are each provided to extend linearly in the axial direction, and the convex portion 436 is provided in the split core 435 in the range from one axial end to the other axial end. The convex portion 436 and the concave portion 477 each correspond to an "engagement portion".

A resin layer RS1 made of synthetic resin is formed between the stator holder 460 and the split core 435.

When the split core 435 is formed by stacking long, plate-shaped core sheets, it is preferable to first stack multiple core sheets to create a rectangular parallelepiped laminated core, and then bend the laminated core with a predetermined curvature. This manufacturing method makes it possible to easily accommodate stator holders 460 with different outer diameter dimensions of the cylindrical part while using a common laminated core. In addition, it is easily compatible with not only outer rotor type rotating electric machines, but also inner rotor type rotating electric machines.

The partial windings 441A and 441B are assembled on the opposite side of the stator holder 460 in the split core 435, i.e., on the radial outside of the split core 435. The circumferential dimension of the split core 435 is the same as the circumferential width of the partial windings 441A and 441B. In this case, the split cores 435 are provided in one-to-one correspondence with the partial windings 441A, and a pair of intermediate conductor portions 442 of each partial winding 441A is fixed to each split core 435. In addition, the partial winding 441B is provided so as to straddle the boundary between two circumferentially adjacent split cores 435. A resin layer RS2 made of synthetic resin is formed between the intermediate conductor portions 442 of each partial winding 441A and the split core 435.

In each of the partial windings 441A, 441B, the crossover portion of one partial winding 441A is on the radial inside and the crossover portion of the other partial winding 441B is on the radial outside, so that the crossover portions overlap in the circumferential direction. In this case, the crossover portion of the partial winding 441A is on the split core 435 side of the radial inside or outside, and the crossover portion of the partial winding 441B is on the opposite side of the split core 435 of the radial inside or outside (see Figure 50).

Generally, the stator core 432 is attached to the stator holder 460 by fitting and fixing with a predetermined tightening margin, such as shrink fitting or press fitting. In this embodiment, the stator core 432 is attached by fixing each of the split cores 435 to the stator holder 460. In this case, since it is difficult to generate a radial assembly force, a gap occurs between the stator holder 460 and the stator core 432, which may cause rattling or a decrease in heat dissipation. However, the resin layer RS1 is formed between the stator holder 460 and the split core 435, which suppresses rattling and a decrease in heat dissipation. In a rotating electric machine with an outer rotor structure, it is necessary to heat the stator core 432 on the radial outer side of the stator holder 460 and the stator core 432 to perform shrink fitting, and there is a possibility that characteristics may change due to heating, but the configuration using the split core 435 eliminates such concerns.

With a configuration in which a resin layer RS1 is interposed between the stator holder 460 and the split core 435, and a resin layer RS2 is interposed between the partial windings 441A, 441B and the split core 435, the heat generated by the partial windings 441A, 441B can be suitably released toward the stator holder 460, which has a refrigerant passage 463 as a cooling section, improving heat dissipation. The resin layers RS1, RS2 are preferably formed from a material with high thermal conductivity (for example, a resin with a thermal conductivity of 0.3 W/mK or more).

The resin layers RS1 and RS2 are preferably formed from the same resin material. However, the resin layers RS1 and RS2 may be made from different resin materials, and the resin material of the resin layer RS2 on the partial windings 441A, 441B side may have a higher adhesive strength than the resin material of the resin layer RS1 on the stator holder 460 side. In this case, the split core 435 on the stator holder 460 side is fixed with uneven engagement, whereas the split core 435 and the partial windings 441A, 441B are fixed not by engagement, and it is desirable that the adhesive strength is increased to improve reliability.

Alternatively, the resin material of the resin layer RS2 on the partial windings 441A, 441B side may have a higher thermal conductivity than the resin material of the resin layer RS1 on the stator holder 460 side. In this case, by increasing the thermal conductivity of the resin layer RS2 on the coil side, which is the heat source, it is possible to improve heat dissipation. Also, since it is considered that gaps are more likely to occur between the partial windings 441A, 441B side and the split core 435 than on the stator holder 460 side, it is also possible to improve heat dissipation by increasing the thermal conductivity of the resin layer RS2.

As described above, by providing a recess 477 on the stator holder 460 side and a protrusion 436 on the split core 435 side (in other words, no recess is formed on the split core 435 side), it is possible to suppress the generation of cogging torque while achieving the desired positioning effect.

When assembling the stator 430 to the stator holder 460, the split core 435 and the partial winding 441A are integrated as shown in FIG. 58, and the integrated body is assembled to the cylindrical portion of the stator holder 460, i.e., the outer cylinder member 461. At this time, the positioning of each split core 435 is performed by the recess 477 on the stator holder 460 side and the protrusion 436 on the split core 435 side, and the split core 435 is assembled with the resin layer RS1 interposed between the stator holder 460 and the split core 435. The split core 435 can be assembled from the radial direction. Therefore, unlike assembly from the axial direction, the resin material applied to at least either the stator holder 460 side or the split core 435 side is less likely to be scraped off.

Then, after the split core 435 and the partial winding 441A are assembled to the stator holder 460, the partial winding 441B is assembled. When each partial winding 441A, 441B is assembled, the partial winding 441A is arranged so that the boundary between the split cores 435 arranged in the circumferential direction corresponds to the boundary between the partial windings 441A in the circumferential direction. Furthermore, the partial winding 441B is arranged so as to straddle the boundary between the split cores 435 arranged in the circumferential direction.

The stator 430 may be attached to the stator holder 460 by first attaching each split core 435 to the stator holder 460, and then attaching the partial winding 441A to each split core 435, and then attaching the partial winding 441B.

The following configuration can also be used for the concave-convex engagement between the stator holder 460 and the split core 435.

Figure 59(a) is a front view of the split core 435 as viewed from the radial inside (the stator holder 460 side), and Figure 59(b) is a cross-sectional view taken along line B-B in Figure 59(a). In the configuration shown in Figures 59(a) and (b), the split core 435 has a convex portion 436 in a range that is a part of the area between one axial end and the other axial end. Although not shown, a concave portion 477 is also provided in the same range in the axial direction on the stator holder 460 side. In this case, it is possible to position the split core 435 and the stator holder 460 not only in the circumferential direction but also in the axial direction by engagement of the concave and convex portions.

In the split core 435 shown in Figures 59(a) and (b), different types (shapes) of core sheets are used for part A1, which has a convex portion 436 in the axial direction, and part A2, which does not have a convex portion 436. Specifically, core sheets with notches and core sheets without notches are used in each part A1 and A2. This split core 435 is preferably manufactured by forming each part A1 and A2 by laminating long plate-shaped core sheets, joining them together, and bending them with a predetermined curvature.

As shown in Fig. 59(c) and (d), the circumferential ends of the split cores 435 arranged in the circumferential direction may overlap each other in the radial direction. In the configuration of Fig. 59(c), the end faces of the circumferential ends of the split cores 435 are oriented to extend obliquely relative to the radial direction, and multiple split cores 435 are arranged in the circumferential direction with the circumferential end faces closely facing each other. In the configuration of Fig. 59(d), a step is formed on the end face of the circumferential end of the split core 435, and the step causes the circumferential ends of the split cores 435 adjacent in the circumferential direction to overlap each other in the radial direction. OL in the figure corresponds to the overlapping portion where the split cores 435 overlap each other in the radial direction. According to each of these configurations, it is possible to suppress the deterioration of magnetic performance at the boundary (seam) between the split cores 435 in the stator core 432.

In the configuration of FIG. 59(d), the thickness of the overlapping portion of the circumferential end of the split core 435 differs between the stator holder 460 side (lower side of the figure) and the stator winding 431 side (upper side of the figure), with the stator winding 431 side being thicker. This makes it possible to effectively suppress deterioration of magnetic resistance in a configuration in which the circumferential end of the split core 435 is stepped.

As shown in FIG. 59(e), the engagement between the stator holder 460 and the split core 435 may be configured such that a convex portion is provided on the stator holder 460 side and a concave portion is provided on the split core 435 side. In this case, taking into consideration that the stator holder 460 is provided with an annular refrigerant passage 463, the formation of a convex portion rather than a concave portion on the stator holder 460 side makes it less likely to affect the formation of the refrigerant passage 463.

In the split core 435 shown in FIG. 60, the core sheets are stacked with a circumferential misalignment, and this misalignment forms a step on the circumferential end face of the split core 435. Similarly, the protrusions 436 of the split core 435 are also misaligned in the axial direction. It is preferable that each core sheet is stacked with a circumferential misalignment for each of the multiple sheets. However, each core sheet may also be circumferentially misaligned for each sheet in the stacking direction.

When each split core 435 is assembled to the stator holder 460, the steps (concave and convex) formed on the circumferential end faces of each split core 435 engage with each other. In other words, the steps on the circumferential end faces of the split core 435 formed by the circumferential misalignment of the core sheet allow the split cores 435 lined up in the circumferential direction to engage with each other. This makes it possible to suppress deterioration of the magnetic resistance in the stator core 432.

As shown in FIG. 61(a), the split core 435 may have a protrusion 436 extending obliquely with respect to the axial direction. A recess may be provided instead of the protrusion 436. This makes it possible to suppress the generation of cogging torque caused by providing the split core 435 with a protrusion or recess.

As shown in FIG. 61(b), both circumferential end faces of the split core 435 may be inclined in the same direction relative to the axial direction, so that the split core 435 has a substantially parallelogram shape when viewed from the front.

As shown in FIG. 61(c), the circumferential end faces of the split core 435 may be inclined in opposite directions relative to the axial direction, so that the split core 435 has a substantially trapezoidal shape (isosceles trapezoidal shape) when viewed from the front.

Next, we will explain the coil end cover 490.

As shown in Figures 47 and 50, the coil end cover 490 is annular and is attached to the end plate 471 of the stator holder 460. In other words, the coil end cover 490 is provided on the coil end portion on one axial end side of the stator 430, i.e., on the coil end portion on the side where the crossover portion 443 is bent radially outward among the coil end portions on both axial ends of the stator 430. This coil end cover 490 axially covers the coil end portion of the stator winding 431 and positions each partial winding 441A, 441B on the one axial end side.

The coil end cover 490 has a number of mounting holes 492 arranged in the circumferential direction, and the coil end cover 490 is attached to the stator holder 460 by fasteners such as fixing pins and screws in each of the mounting holes 492. The stator holder 460 and the coil end cover 490 together correspond to the "armature holding member."

In this embodiment, in the stator unit 420, the partial windings 441A and 441B are fixed to each divided core 435 of the stator core 432 and the coil end cover 490 by mechanical coupling, and the specific configuration is described below.

As explained in FIG. 55, in each partial winding 441A, 441B, radially inward of the intermediate conductor portion 442, the protrusion 455a of the bracket 455 provided on the insulating cover 451 of the partial winding 441A and the protrusion 458a of the bracket 458 provided on the insulating cover 454 of the partial winding 441B overlap in the axial direction, and the positions of the through holes 455b, 458b of each protrusion 455a, 458a coincide in a plan view.

On the other hand, as shown in FIG. 49, a recess 437 is formed on the end face of each split core 435 at one axial end, and when a cylindrical stator core 432 is formed by multiple split cores 435, multiple recesses 437 are arranged at predetermined intervals in the circumferential direction.

Each split core 435 is assembled radially inward of each partial winding 441A, 441B. In this case, the through holes 455b, 458b of the brackets 455, 458 in the insulating covers 451, 454 are aligned with the recesses 437 in the axial end surface of the stator core 432 radially inward of the intermediate conductor portions 442 of each partial winding 441A, 441B. Then, a connecting member, for example a metal fixing pin, is assembled to the through holes 455b, 458b and the recesses 437, thereby fixing each partial winding 441A, 441B to each split core 435.

In addition, the coil end cover 490 is provided with a plurality of through holes 491 at equal intervals in the circumferential direction, and each of the plurality of through holes 491 corresponds to the through hole 456b of the bracket 456 in the insulating cover 452 of the partial winding 441A and the through hole 457b of the bracket 457 in the insulating cover 453 of the partial winding 441B. The coil end cover 490 corresponds to the opposing portion that faces the bridge portion of the partial windings 441A and 441B. In this case, with the coil end cover 490 attached to one axial end side of the stator 430, the positioning of each through hole 491 on the coil end cover 490 side is performed with respect to the through holes 456b and 457b on the insulating covers 452 and 453 sides, and further, a coupling member, for example a metal fixing pin, is assembled in each through hole 491, thereby fixing the coil end cover 490 to the stator 430. In this state, the axial end of each partial winding 441A, 441B is fixed by the coil end cover 490.

Assuming that the coil end cover 490 is attached to the stator winding 431, the multiple through holes 491 aligned in the circumferential direction are positioned radially outward of the transition portion 444 (in other words, the position of the intermediate conductor portion 442) of the stator winding 431 that is not bent radially and extends axially, and the multiple mounting holes 492 aligned in the circumferential direction are positioned radially inward of the transition portion 444 of the stator winding 431.

In short, the structure of fixing the partial windings 441A, 441B to each split core 435 and coil end cover 490 can be summarized as follows: At one axial end of each partial winding 441A, 441B, the bridge portion 443 of the partial winding 441A is bent radially inward, and the bridge portions 443, 444 of each partial winding 441A, 441B are fixed to the split core 435. On the other hand, at the other axial end of each partial winding 441A, 441B, the bridge portion 443 of the partial winding 441B is bent radially outward, and the bridge portions 443, 444 of each partial winding 441A, 441B are fixed to the coil end cover 490.

Regarding the fixing of the split core 435 to each partial winding 441A, 441B, the recess 437 of the split core 435 corresponds to the "fixing portion", and the through holes 455b, 458b of the brackets 455, 458 of the insulating covers 451, 454 correspond to the "fixed portion". Also, regarding the fixing of the coil end cover 490 to each partial winding 441A, 441B, the through hole 491 of the coil end cover 490 corresponds to the "fixing portion", and the through holes 456b, 457b of the brackets 456, 457 of the insulating covers 452, 453 correspond to the "fixed portion".

Next, the wiring module 480 will be described. The wiring module 480 is a winding connection member that is electrically connected to each partial winding 441A, 441B in the stator winding 431. The partial windings 441 of each phase are connected in parallel or series by this wiring module 480, and the phase windings of each phase are connected at the neutral point. As shown in FIG. 43, the wiring module 480 is provided on one of the axial ends of the stator 430, specifically, on the side of the end plate portion 414 of the rotor carrier 411 (opposite the coil end cover 490).

More specifically, the stator winding 431 has a partial winding 441A bent radially inward at one axial end and a partial winding 441B bent radially outward at the other axial end, with the bent side of the partial winding 441A and the non-bent side of the partial winding 441B facing the end plate portion 414 of the rotor carrier 411, and these partial windings 441A, 441B are arranged side by side with some overlap in the circumferential direction. Furthermore, a wiring module 480 is provided on one of the axial ends of the stator winding 431, on the end plate portion 414 side of the rotor carrier 411.

As shown in FIG. 47, the wiring module 480 has an annular portion 481 that forms a ring shape, and a plurality of connection terminals 482 that are arranged in a circumferential direction along the annular portion 481. The annular portion 481 is formed in a ring shape from an insulating material such as resin. Wiring for each phase and a neutral point wiring (both not shown) are embedded in the annular portion 481, and a connection terminal 482 is electrically connected to each of these wirings. The connection terminals 482 are provided for each partial winding 441, and are fixed so that they extend in the axial direction.

In addition, in the wiring module 480, a bus bar 483 is connected to each phase of wiring embedded in the annular portion 481. Each bus bar 483 is part of the power wiring for U-phase power, V-phase power, and W-phase power, respectively, and is provided so as to protrude radially inward.

In the stator winding 431, at the lower end of FIG. 47, the transition parts 444 that are not bent in the radial direction are arranged in a ring shape, and the wiring module 480 is provided on the radial inside of the transition parts 444. In other words, the ring part 481 of the wiring module 480 is formed with a smaller diameter than the annular part formed by the transition parts 444 arranged in the circumferential direction. The ring part 481 is provided with a mounting member 484 for mounting the wiring module 480 to the stator holder 460. The mounting member 484 is made of, for example, a metal plate, and has multiple mounting parts at predetermined intervals in the circumferential direction.

Each bus bar 483 of the wiring module 480 is connected to a power line 485 that supplies power to the stator winding 431 for each phase. The power lines 485 are arranged in a line in the circumferential direction and extend in the axial direction. The power lines 485 may be conductors that are rigid bodies such as metal bus bars, or may be conductors that are inserted into rigid tubes such as synthetic resin. This makes it possible to reduce the influence of vibrations even if they occur in the rotating electric machine 400. The power lines 485 may also be made of flexible harnesses. Each power line 485 is connected to a terminal block 475 provided on the end plate portion 471 of the inner cylinder member 462.

Next, the overall configuration of the rotating electric machine 400 including the rotor 410 and stator unit 420 described above will be described with reference to Figures 43 and 62. Note that Figure 62 is an exploded cross-sectional view of the rotating electric machine 400 in which the spindle 401 and the stator unit 420 are integrated as a fixed object, and the hub 402 and the rotor 410 are integrated as a rotating object.

The spindle 401 is attached to the stator unit 420 in a state where it is inserted into the through-hole 472 of the stator holder 460. More specifically, the fixed shaft portion 404 of the spindle 401 is inserted into the through-hole 472 of the stator holder 460, and in this state, the spindle 401 is fixed to the end plate portion 471 of the inner cylinder member 462 by a fastener such as a bolt. On the other hand, the hub 402 is fixed to the rotor 410. More specifically, the hub 402 is inserted into the through-hole 414a of the rotor carrier 411, and in this state, the hub 402 is fixed to the end plate portion 414 by a fastener such as a bolt.

The fixed shaft portion 404 of the spindle 401 is inserted into the insertion hole 406 of the hub 402, and the stator unit 420 and the rotor 410 are disposed at positions that are radially inward and outward from each other. As shown in FIG. 62, the integrated body of the spindle 401 and the stator unit 420 has an annular space S1 formed around the fixed shaft portion 404 of the spindle 401. The integrated body of the hub 402 and the rotor 410 has an annular space S2 formed around the hub 402. The integrated body of the spindle 401 and the stator unit 420 and the integrated body of the hub 402 and the rotor 410 are assembled together such that the hub 402 enters the annular space S1 and the stator unit 420 enters the annular space S2.

Bearings 407, 408 are attached between the fixed shaft portion 404 of the spindle 401 and the hub 402, and the hub 402 is rotatably supported by the bearings 407, 408. In other words, the hub 402 and the rotor 410 are rotatably supported by the bearings 407, 408 relative to the spindle 401 and the stator unit 420. In the bearings 407, 408, the inner ring is attached to the fixed shaft portion 404 side, and the outer ring is attached to the hub 402 side.

When the integrated unit of the spindle 401 and stator unit 420 and the integrated unit of the hub 402 and rotor 410 are assembled together, a rotor cover 511 is fixed to the open end side of the rotor 410, i.e., the opposite side of the hub 402 in the axial direction (the opposite side of the end plate portion 414 of the rotor carrier 411). The rotor cover 511 is in the shape of an annular plate, and is fixed to the rotor carrier 411 by a fastener such as a bolt, with a bearing 512 interposed between the rotor cover 511 and the inner cylinder member 462.

When the integrated body of the spindle 401 and the stator unit 420 and the integrated body of the hub 402 and the rotor 410 are assembled together, a closed annular space SA that is closed in the axial and radial directions is formed on the inner periphery of the stator unit 420. A resolver 520 is provided in the closed space SA as a rotation sensor. The resolver 520 is annular, and has a resolver stator fixed to the inner cylinder member 462 of the stator unit 420, which is the fixed body side, and a resolver rotor fixed to the hub 402, which is the rotating body side. The resolver rotor is disposed facing the radially inner side of the resolver stator.

In this embodiment, as described above, a plurality of protrusions 473 are provided at predetermined intervals in the circumferential direction on the inner periphery side of the inner cylinder member 462 in the stator holder 460 (see FIG. 56). The resolver 520 (resolver stator) is attached to the axial end surface of the protrusions 473 of the inner cylinder member 462.

As shown in FIG. 44, the resolver 520 has a terminal portion 521 on a portion of its circumference, and a resolver signal line 522 is connected to the terminal portion 521. As shown in FIGS. 42 and 43, the resolver signal line 522 is guided to the outside of the rotating electric machine (the axial end of the rotating electric machine 400) through an insertion hole 476 provided in the end plate portion 471 of the inner cylinder member 462. The insertion hole 476 may be sealed with a sealing member such as a grommet. A signal line terminal portion connected to the resolver signal line 522 may be provided on the axial end surface of the inner cylinder member 462.

The present embodiment described above provides the following excellent effects:

In the rotating electric machine 400, the stator core 432 is formed into a cylindrical shape by a plurality of split cores 435 arranged in the circumferential direction, and each of the split cores 435 is assembled to the stator holder 460. In this case, unlike a configuration in which the annular stator core 432 and the stator holder 460 are fitted and fixed by shrink fitting or press fitting, there is a concern that the gap between the stator core 432 and the stator holder 460 may cause rattling or reduce heat dissipation from the stator 430 side to the stator holder 460. In this regard, since each split core 435 is assembled to the stator holder 460 with a resin layer RS1 interposed between the stator holder 460 and each split core 435, inconveniences caused by the gap between the stator core 432 and the stator holder 460 can be suppressed. In particular, when using a stator 430 with a teethless structure, the stator winding 431 is not engaged with the teeth of the stator core 432, which may cause the stator core 432 (each divided core 435) to wobble, resulting in problems such as misalignment of the stator winding 431, but this is also suppressed. As a result, the stator core 432 can be properly assembled.

The stator holder 460 and the split core 435 have engagement portions (protrusions 436 and recesses 477) that can engage in the circumferential direction at the radially opposing portions of the stator holder 460 and the split core 435, which makes it possible to suppress circumferential positional deviation of each split core 435 relative to the stator holder 460.

The circumferential dimension of the split core 435 is the same as the circumferential width of the partial windings 441A, 441B, which makes it easy to assemble the partial windings 441A, 441B to the split core 435.

By arranging the partial winding 441B so as to straddle the boundary between the split cores 435 arranged in the circumferential direction, misalignment of the split cores 435 at the boundary between the split cores 435 is less likely to occur. This allows for optimal assembly of the split cores 435.

The partial windings 441 are configured to include a partial winding 441A (first partial winding) whose crossover portion is on the split core 435 side of the radial inside or outside, and a partial winding 441B (second partial winding) whose crossover portion is on the opposite side of the split core 435 of the radial inside or outside, so that the partial windings 441 can be suitably arranged without interfering with each other. In addition, of the partial windings 441A and 441B, the partial winding 441A whose crossover portion is on the split core 435 side and which is assembled first to the split core 435 has both circumferential ends corresponding to both circumferential ends of the split core 435, making it easy to assemble each partial winding 441 to each split core 435 (stator core 432).

The partial windings 441A and 441B are fixed to the split core 435 by the recesses 437 (fixing parts) provided in the split core 435. This allows the split core 435 and the partial windings 441A and 441B to be suitably assembled in the stator 430 with a teethless structure.

By providing insulating covers 451-454 on the bridge sections of partial windings 441A, 441B, mutual insulation can be suitably achieved even when the bridge sections of partial windings 441A, 441B are arranged to overlap each other in the circumferential direction. In addition, by making the through holes 455b, 458b of brackets 455, 458 in insulating covers 451, 454 fixed parts that are fixed to the fixed part on the split core 435 side, it is possible to give insulating covers 451-454 an insulating function that insulates partial windings from each other and a function of fixing partial windings 441A, 441B to split core 435.

In the stator unit 420, the outer tube member 461 (cylindrical portion) of the stator holder 460 is provided on one side of the stator core 432 in the radial direction, and the stator winding 431 is provided on the other side. The partial windings 441A, 441B are fixed to through holes 491 of a coil end cover 490 integrated with the stator holder 460. In this case, the split core 435 is interposed between the outer tube member 461 of the stator holder 460 and each partial winding 441A, 441B, and is held in a sandwiched state between the two by fixing them together. This restricts misalignment of the split core 435, making it possible to properly assemble the split core 435 to the stator holder 460.

A resin layer RS1 is formed between the stator holder 460 and each split core 435, and a resin layer RS2 is also formed between each split core 435 and the partial windings 441A, 441B (stator winding 431). This allows heat generated in the stator winding 431 to be effectively transferred to the stator holder 460 via each split core 435, improving heat dissipation.

(Modification of the second embodiment)
As shown in Fig. 63, one split core 435 may be provided for two partial windings 441A. Alternatively, one split core 435 may be provided for three or more partial windings 441A. However, the number of split cores 435 in the stator core 432 is two or more and is half or less than the number of partial windings 441A. With the above configuration, the partial windings 441 can be easily attached to the split cores 435.

Here, if the circumferential width of the partial windings 441A, 441B is L, the circumferential dimension of the stator core 432 is L×n (n is a natural number), and a divisor of "n" other than 1 and n is D, then the circumferential dimension of the split core 435 is L×D. In this embodiment, the circumferential dimension of the stator core 432 is L×18, and the divisors D of "18" other than 1 and 18 are 2, 3, 6, and 9. In this case, in the configuration of FIG. 63, the circumferential dimension of the split core 435 is "L×2".

- The following configuration may be used as a method of fixing the split core 435 to the stator holder 460. Note that in the stator holder 460 and split core 435 shown in Figures 64(a) to (c), the configuration related to the concave-convex engagement between the two is omitted.

As shown in FIG. 64(a), a configuration may be used in which a fixing device 531 is attached between each of the split cores 435 adjacent in the circumferential direction with its tip inserted into the stator holder 460. The fixing device 531 is a wedge-shaped member with a sharp tip, and has a length dimension longer than the radial thickness dimension of the split cores 435. The fixing device 531 may be a needle-shaped member or a long plate-shaped member extending in the axial direction. The fixing device 531 is preferably made of a magnetic material, but may also be made of a non-magnetic material. With this configuration, the circumferential position of each split core 435 is regulated by the fixing device 531. This makes it possible to suppress circumferential positional deviation of each split core 435.

In addition, a pilot hole may be formed in the stator holder 460 beforehand, and the fastener 531 may be inserted into the pilot hole. It is sufficient that the fastener 531 is fixed at at least one location in the circumferential direction between each of the split cores 435 arranged in the circumferential direction.

As shown in FIG. 64(b), the fixing device 531 may have an engagement portion that engages with the radial end face of each split core 435, more specifically, the circumferential end face on the opposite side to the holder. This makes it possible to prevent the split cores 435 from being displaced radially.

As shown in FIG. 64(c), the fixing device 531 may be inserted into the circumferential middle portion of each split core 435. The fixing device 531 only needs to be provided on at least one of the split cores 435 arranged in the circumferential direction. This allows each split core 435 to be properly fixed. It is also possible to omit the engagement portion of the fixing device 531 that engages with the radial end face of the split core 435 (more specifically, the circumferential end face on the opposite side to the holder).

- As shown in FIG. 65(a), the split core 435 may have portions with different radial thickness dimensions. Specifically, the split core 435 has a protruding portion 438 with a large radial thickness dimension at one axial end, and is assembled to the stator holder 460 with the protruding portion 438 extending to the opposite side of the stator holder 460. In this case, the axial length of the split core 435 is longer than the coil side portion, and the protruding portion 438 is positioned axially outward of the bridge portions of each partial winding 441A, 441B.

As described above, a recess 437 is provided at one axial end of the split core 435, and a recess 439 is provided in the protruding portion 438 at the other axial end. These recesses 437, 439 correspond to fixing portions for fixing the partial windings 441A, 441B, respectively.

As shown in FIG. 65(b), at one axial end of the split core 435, the bridge portions of the partial windings 441A and 441B are fixed using the recesses 437, and at the other axial end of the split core 435, the bridge portions of the partial windings 441A and 441B are fixed using the recesses 439 of the protruding portions 438.

In the split core 435 shown in FIG. 65, the overhanging portion 438 and the other portions are formed by stacking different types of core sheets. In other words, the split core 435 has the overhanging portion 438 as a portion that faces the coil end portion of the partial windings 441A, 441B (stator winding 431) in the axial direction, and different types of core sheets are used for the overhanging portion 438 (coil end facing portion) and the other portions in the axial direction. In addition, the core sheet material of the overhanging portion 438 and the other portions may be different from each other. For example, the magnetic permeability and strength may be different from each other. In this case, the overhanging portion 438 may be a non-magnetic material. Or, in the split core 435, the overhanging portion 438 may be stronger than the other portions. According to the above configuration, it is possible to preferably realize a split core 435 that is required to have a different shape in the axial direction (core sheet stacking direction).

- The following configuration may be used for the partial windings 441A, 441B of the stator winding 431.

In the configuration shown in Fig. 66 (a) and (b), one of the two types of partial windings 441A and 441B, the partial winding 441A, is approximately C-shaped in side view, and the other partial winding 441B is approximately I-shaped in side view. Of the partial windings 441A and 441B, the partial winding 441A whose transition portion is on the split core 435 side is pre-attached to the split core 435, and the partial winding 441B whose transition portion is on the opposite side of the split core 435 is post-attached to the split core 435. The partial winding 441A is a first partial winding whose transition portion is on the split core 435 side (radially inner side) of the radial inside and outside, and the partial winding 441B is a second partial winding whose transition portion is on the opposite side of the split core 435 (radially outer side) of the radial inside and outside.

As shown in FIG. 66(b), the bridge portions of the partial windings 441A, 441B are fixed by fixing pins inserted into recesses 437 of the split core 435. In this configuration, recesses 437 are provided on both axial end faces of the split core 435, and each bridge portion on both axial ends of the partial windings 441A, 441B is fixed to the split core 435.

In addition to the above, each of the bridge portions at both axial ends of the partial windings 441A and 441B may be fixed to the stator holder 460, i.e., not directly fixed to the split core 435.

- The partial windings 441A, 441B may be assembled to each cylindrically arranged split core 435 as shown in FIG. 67. In FIG. 67, the partial winding 441A is arranged so as to straddle the boundary between the split cores 435 arranged in the circumferential direction. The partial winding 441B is also arranged so that the boundary between the split cores 435 arranged in the circumferential direction corresponds to the boundary between the partial windings 441B in the circumferential direction.

- In the above embodiment, the stator winding 431 is configured to use multiple partial windings 441A, 441B, and a split core 435 is provided corresponding to the partial winding 441A, but this may be changed. For example, the stator winding 431 may be wave wound. In this case, after arranging multiple split cores 435 side by side in the cylindrical portion of the stator holder 460, a wave wound coil may be attached to the circumferential outside of the split cores 435.

- In the above configuration, as shown in FIG. 47, the stator holder 460 and the coil end cover 490 are provided separately in the stator unit 420, and the coil end cover 490 is fixed to the stator holder 460 by fasteners such as fixing pins and screws, but this configuration may be changed. Specifically, as shown in FIG. 68, the coil end cover 497 is provided in a state where it is integrated with the end plate portion 471 of the stator holder 460. In this case, the coil end cover 497 is formed in the stator holder 460 in a brim-like shape that extends radially outward, and the coil end portion (crossover portion 443) of each partial winding 441A, 441B is fixed by the coil end cover 497.

- In the second embodiment, the rotating electric machine 400 has an outer rotor structure, but this may be modified to have an inner rotor structure. In a rotating electric machine with an inner rotor structure, the stator is provided on the radial outside and the rotor is provided on the radial inside. Even in such a configuration, it is preferable to use a configuration in which the stator core is formed from multiple split cores as described above, or an associated configuration, as appropriate.

- The rotating electric motor 400 may be used for purposes other than a vehicle's traction motor, and may be a rotating electric motor used in a wide range of moving objects, including aircraft, or a rotating electric motor used in industrial or household electrical equipment.

The disclosure in this specification is not limited to the exemplified embodiments. The disclosure includes the exemplified embodiments and modifications based thereon by those skilled in the art. For example, the disclosure is not limited to the combination of parts and/or elements shown in the embodiments. The disclosure can be implemented in various combinations. The disclosure can have additional parts that can be added to the embodiments. The disclosure includes the omission of parts and/or elements of the embodiments. The disclosure includes the substitution or combination of parts and/or elements between one embodiment and another embodiment. The technical scope of the disclosure is not limited to the description of the embodiments. Some technical scopes disclosed are indicated by the description of the claims, and should be interpreted as including all modifications within the meaning and scope equivalent to the description of the claims.

400... rotating electric machine, 410... rotor, 430... stator, 431... stator winding, 432... stator core, 435... split core, 460... stator holder, RS1... resin layer.

Claims (14)

A field element (410) having a plurality of magnetic poles;
A toothless armature (430) including a polyphase armature winding (431) and an armature core (432) integrally provided on the radially inner side or the radially outer side of the armature winding;
an armature holding member (460) attached to the radially inner or outer side of the armature core on the opposite side to the armature winding;
A rotating electric machine (400) comprising: the field element and the armature are provided so as to face each other in a radial direction,
The armature core is formed in a cylindrical shape by a plurality of divided cores (435) arranged in a circumferential direction,
each of the split cores is assembled to the armature holding member with a resin layer (RS1) interposed between the armature holding member and each of the split cores ;
A rotating electric machine in which a fixing device (531) is attached to at least one location between each of the divided cores arranged in the circumferential direction with its tip end inserted into the armature holding member . A field element (410) having a plurality of magnetic poles;
A toothless armature (430) including a polyphase armature winding (431) and an armature core (432) integrally provided on the radially inner side or the radially outer side of the armature winding;
an armature holding member (460) attached to the radially inner or outer side of the armature core on the opposite side to the armature winding;
A rotating electric machine (400) comprising: the field element and the armature are provided so as to face each other in a radial direction,
The armature core is formed in a cylindrical shape by a plurality of divided cores (435) arranged in a circumferential direction,
each of the split cores is assembled to the armature holding member with a resin layer (RS1) interposed between the armature holding member and each of the split cores ;
A rotating electric machine in which a fixing device (531) is attached to a circumferential middle portion of at least one of the split cores arranged in the circumferential direction with its tip portion inserted into the armature holding member . The armature winding has a phase winding consisting of a plurality of partial windings (441) for each phase,
The partial windings each have a pair of intermediate conductor portions (442) spaced a predetermined distance apart in the circumferential direction, and transition portions (443, 444) that are provided at one and the other axial ends and connect the pair of intermediate conductor portions in an annular manner, and the intermediate conductor portions of different partial windings are arranged adjacent to each other in the circumferential direction,
3. The rotating electric machine according to claim 1, wherein the circumferential dimension of the split core is the same as the circumferential width L of the partial winding, or the circumferential dimension of the armature core is the circumferential width L x n, where D is a divisor of "n" other than 1 or n, and is L x D. A field element (410) having a plurality of magnetic poles;
A toothless armature (430) including a polyphase armature winding (431) and an armature core (432) integrally provided on the radially inner side or the radially outer side of the armature winding;
an armature holding member (460) attached to the radially inner or outer side of the armature core on the opposite side to the armature winding;
A rotating electric machine (400) comprising: the field element and the armature are provided so as to face each other in a radial direction,
The armature core is formed in a cylindrical shape by a plurality of divided cores (435) arranged in a circumferential direction,
each of the split cores is assembled to the armature holding member with a resin layer (RS1) interposed between the armature holding member and each of the split cores ;
The armature winding has a phase winding consisting of a plurality of partial windings (441) for each phase,
The partial windings each have a pair of intermediate conductor portions (442) spaced a predetermined distance apart in the circumferential direction, and transition portions (443, 444) that are provided at one and the other axial ends and connect the pair of intermediate conductor portions in an annular manner, and the intermediate conductor portions of different partial windings are arranged adjacent to each other in the circumferential direction,
A rotating electric machine in which the circumferential dimension of the split core is the same as the circumferential width L of the partial winding, or the circumferential dimension of the armature core is the circumferential width L x n, where D is a divisor of "n" other than 1 or n, and is L x D. 5. The rotating electric machine according to claim 3 , wherein the plurality of partial windings include a partial winding that is provided so as to straddle a boundary between two of the divided cores that are adjacent in the circumferential direction. In the armature winding, one of the pair of intermediate conductor portions in the partial winding of another phase is disposed between the pair of intermediate conductor portions in the partial winding, and between the partial windings whose jumper portions overlap in the circumferential direction, the jumper portion of one partial winding is located on the radially inner side and the jumper portion of the other partial winding is located on the radially outer side,
The plurality of partial windings include a first partial winding (441A) in which the transition portion is on the divided core side of the radial inside or outside, and a second partial winding (441B) in which the transition portion is on the opposite side of the divided core of the radial inside or outside,
A rotating electric machine as described in any one of claims 3 to 5, wherein the first partial winding is arranged so that the boundary portions between the divided cores arranged in the circumferential direction correspond to the boundary portions between the first partial windings in the circumferential direction, and the second partial winding is arranged so as to straddle the boundary portions between the divided cores arranged in the circumferential direction. The rotating electric machine according to any one of claims 3 to 6 , wherein the split core is provided with fixing portions (437, 439) for fixing the partial windings. Insulating members (451, 454) for insulating the partial windings from each other are attached to the transition portions of the partial windings,
8. The rotating electric machine according to claim 7 , wherein the insulating member is provided with a fixed portion (455b, 458b) fixed to the fixed portion. The rotating electric machine according to any one of claims 3 to 8 , wherein the armature holding member has an opposing portion (490, 497) that faces the jumper portion of the partial winding, and a fixing portion (491) that fixes the partial winding is provided on the opposing portion. The rotating electric machine according to any one of claims 1 to 9 , wherein the armature holding member and the divided core are provided at their radially opposing portions with engaging portions (436, 477) that are engageable in a circumferential direction. The rotating electric machine according to any one of claims 1 to 10, wherein the split core is formed by stacking a plurality of core sheets in the axial direction, and two or more types of the core sheets are stacked together. The rotating electric machine according to any one of claims 1 to 11, wherein each of the split cores arranged in the circumferential direction has overlapping portions (OL) at their circumferential ends that overlap each other in the radial direction. The split core is formed by stacking a plurality of core sheets in the axial direction,
The core sheets are laminated in a state including a circumferential misalignment, so that a step is formed on the circumferential end surface of the split core,
13. The rotating electric machine according to claim 1, wherein each of the split cores arranged in the circumferential direction is assembled to the armature holding member in a state in which steps on the circumferential end faces of the split cores are engaged with each other. A rotating electric machine according to any one of claims 1 to 13, in which a second resin layer (RS2) is provided between each of the split cores and the armature winding.

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