JP3770263B2 - Manufacturing method of rotating electrical machine - Google Patents

Description

  The present invention relates to a rotating electrical machine. More specifically, the present invention relates to the structure of a stator of a rotating electric machine, and is suitable for use in, for example, a vehicle AC generator driven by an engine.

  In recent years, rotating electrical machines such as generators driven by the engine have been used to reduce the number of idle rotations of vehicles as a countermeasure to environmental problems, to reduce the weight to improve fuel efficiency, and to narrow the engine room to secure passenger compartment space. Therefore, there is a demand for miniaturization, high output, and high efficiency.

  In contrast, in WO98 / 54823, a stator winding is formed by a plurality of conductor segments, and ends of conductor segments extending from different layers in different slots are connected to each other, thereby achieving a high space factor and low resistance. An automotive alternator that realizes windings and meets the above requirements is shown.

On the other hand, since the vehicle AC generator driven by the vehicle engine is directly attached to the engine body via a bracket or the like, vibration from the engine is easily transmitted. In addition, there are electrolytic aqueous solutions such as car shampoo and salt water and foreign substances flying in the engine room, and it is necessary to withstand these and maintain the performance.
WO98 / 54823

  2. Description of the Related Art Conventionally, in the field of rotating electrical machines including vehicle AC generators, technical means such as impregnating a resin material into a winding have been taken in order to maintain the required insulation in the winding. However, application of a large amount of resin material increases material cost and weight. Moreover, application | coating of a large amount of resin materials reduces the surface area which covers the surface of a coil | winding and contributes to heat radiation. Furthermore, applying a large amount of resin material to a winding material such as copper increases the amount of different materials used and deteriorates recyclability.

  In view of the above-described problems, an object of the present invention is to provide an improved rotating electrical machine.

  An object of this invention is to reduce the quantity of the insulating resin material provided to a stator winding.

  An object of this invention is to improve the insulation of a coil | winding, enabling the heat radiation from a coil | winding.

  An object of the present invention is to improve the vibration resistance of a winding while enabling heat dissipation from the winding.

In the present invention, a plurality of joints (33e) are formed on a coil end group (31a, 31b) formed by axially extending a stator winding (31) from one end of a stator core (32). In a method of manufacturing a rotating electrical machine, comprising: a first insulating resin (36) that covers the joint (33e) and a second insulating resin (37) that covers the coil end group (31a, 31b).
The second insulating resin (37) is thinly attached to the coil end group,
Then, the manufacturing method of the rotary electric machine characterized by attaching the said 1st insulating resin (36) thickly only to the vicinity of the said some junction part (33e) is employ | adopted.

  The first insulating resin (36) may be connected to the first insulating resin (36) while maintaining a state where the plurality of joints (33e) are separated from each other. .

  The second insulating resin (37) can be used in a method of manufacturing a rotating electrical machine characterized by passing through a slot of the stator core (32).

  It is possible to employ a method of manufacturing a rotating electrical machine in which the second insulating resin is adhered so that the second insulating resin covers the entire coil end group.

  According to this invention, since the insulating resin that protects the joint exclusively and the insulating resin that increases the rigidity of the coil end group as a whole are selectively used, the insulation protection and the improvement of the mechanical rigidity can be realized with a small amount of resin material. Can do.

  In an embodiment of the present invention, a rotor, a stator core disposed opposite to the rotor, a stator including a stator winding mounted on the stator core, and the rotor and the stator. In a rotating electrical machine having a frame to be supported and a pulley for rotationally driving the rotor outside the frame, the rotor is provided on a pole core having claw-shaped magnetic poles and an end surface of the pole core in the rotation axis direction. The stator winding is formed by a plurality of conductor segments having an inner conductor housed in a slot of the stator core and coil ends exposed on both sides in the axial direction from the slot. The conductor segment has a turn portion, a skew portion that intersects with another conductor segment at the coil end, and a tip portion at the tip of the skew portion, and the coil end has a front end. The first coil end group in which the turn portion is disposed and the second coil end in which a joint portion formed by joining the tip portions is disposed, and the second coil end has an annular shape covering the joint portion. It is characterized by having a resin member and another resin member adhered so as to bridge between the oblique portions.

  As a result, the skew portions of the second coil end are fixed in a state of being separated from each other, so that the rigidity of the entire coil end can be increased and vibration can be reduced. Therefore, the vibration of the joint portion can be suppressed, and a short circuit between the joint portions can be prevented in cooperation with the resin member that covers the joint portion and is connected in an annular shape.

  In the embodiment, the second coil end is arranged on the pulley side. Thereby, since the coil end fixed by the insulating resin is arranged on the pulley side where the electrolytic solution and foreign matter are easily taken into the rotary electric machine, the effect of improving the environmental resistance can be further enhanced.

  In the embodiment, the resin member density of the skew portion of the second coil end is characterized by becoming denser toward the inner side in the radial direction. As a result, even if the electrolyte or foreign matter taken into the rotating electrical machine by the cooling fan reaches the inner peripheral wall of the coil end, the intrusion of these intrusions is prevented and the durability against damage to the coating on the coil end conductor itself is prevented. The environmental resistance can be improved.

  In the embodiment, in a rotating electrical machine formed by joining a plurality of U-shaped conductor segments at their ends to form a stator winding, the U-shaped conductor segment is provided at one end of the stator core, The first coil end group in which the turn portions of the type conductor segments are arranged, and the joint portion formed by joining the end portions of the U-shaped conductor segments are arranged at the other end portion of the stator core. Adopting technical means called a rotating electrical machine, comprising two coil end groups and an insulating resin that adheres thickly to the conductor surface forming the second coil end group from the conductor surface forming the first coil end group can do.

  According to such a configuration, since the insulating resin is attached to the second coil end group in which the joint portions are arranged thicker than the first coil end group in which the turn portions are arranged, the amount of the insulating resin to be used as a whole While being reduced, it is possible to reliably protect the second coil end group that tends to cause insulation failure due to bonding.

  Instead of the above technical means, an insulating resin that covers the joints arranged in the second coil end group and another insulating resin that adheres only to the conductor surface forming the second coil end group are provided. You may employ | adopt the technical means of.

  In such a configuration, in addition to the insulating resin for protecting the joint exclusively, another insulating resin is attached only to the second coil end group, so that the second coil end group can be reliably protected. it can.

  The first coil end group is formed with a cooling air passage that passes through the first coil end group, and a conductor forming the second coil end group is filled with the insulating resin. Means may be employed.

  With this configuration, high heat dissipation can be maintained in the first coil end group.

  In addition, the technical means that the inclination angle of the skew portion in the first coil end group is smaller than the inclination angle of the skew portion in the second coil end group can be adopted.

  In such a configuration, the axial height of the second coil end group including the joint portion can be suppressed, and the insulating resin applied to the second coil end group can easily bridge between the conductors constituting the second coil end group. Therefore, the second coil end group can be reliably protected with a small amount of insulating resin.

  In an embodiment, in a rotating electrical machine in which a plurality of conductor segments are joined at their ends to form a stator winding, the stator winding extends in the axial direction from one end of the stator core. The coil end group thus formed and the insulating resin attached to the coil end group, the insulating resin forming a smoother surface on the radially inner side of the coil end group than on the radially outer side of the coil end group It is possible to employ a technical means called a rotating electrical machine characterized by comprising:

  According to this configuration, it is possible to increase the overall rigidity of the coil end group with a small amount of insulating resin, and to prevent insulation failure in the coil end group. In addition, the surface area that contributes to the heat dissipation of the coil end group can be secured particularly by the radially outer surface.

  The coil end group includes a plurality of joint portions formed by joining the conductor segments, and the insulating resin includes a first insulating resin that covers only the vicinity of the joint portions, and the joint portion. It is possible to employ a configuration including a second insulating resin that covers the entire coil end group.

  According to such a configuration, the insulation resin that protects the joint portion and the insulation resin that increases the rigidity of the coil end group as a whole are selectively used, so that insulation protection and improvement in mechanical rigidity can be realized with a small amount of resin material. Can do.

  The insulating resin preferably employs a technical means for forming a deeper groove on the radially outer side of the coil end group than on the radially inner side.

  In such a configuration, a surface area contributing to heat radiation can be secured by the radially outer surface of the coil end group.

  Embodiments of a rotating electrical machine to which the present invention is applied will be described below. In the following embodiments, the present invention is applied to a vehicular AC generator as a vehicular rotating electrical machine.

(First embodiment)
(Structure) FIGS. 1 to 4 show a first embodiment of the present invention. FIG. 1 is a cross-sectional view showing the overall configuration of an automotive alternator, FIG. 2 is a perspective view of a conductor segment forming a stator winding, FIG. 3 is a plan view of the stator as viewed from the inner periphery, and FIG. It is a fragmentary sectional view in the IV-IV cross section of FIG.

  The vehicle alternator 1 has a pulley 20 that receives a rotational force from an engine. The pulley 20 is fixed together with the rotor 2 on the shaft. The rotor 2 includes a Landel type iron core configured by combining a pair of pole cores 71 and 72, and a field winding 8. Further, a cooling fan is provided at the end of the rotor 2. In this embodiment, the cooling fan 11 is provided on the front side which is one end face, and the cooling fan 12 is provided on the rear side which is the other end face. The cooling fan 11 has a blade that performs blowing in the centrifugal direction and blowing in the axial direction. The cooling fan 12 has a blade that blows air only in the centrifugal direction. The cooling fan 12 is a larger fan than the cooling fan 11 in order to cool the rectifier 5 and the regulator circuit mounted on the frame 4.

  Further, slip rings 9 and 10 are provided on the shaft. The shaft is rotatably supported by the frame 4. A stator 3 is fixed to the frame 4 on the outer peripheral side of the rotor 2.

  The stator 3 includes a stator winding 31 and a stator core 32 that is a laminated core formed by forming a plurality of slots in which the stator winding 31 is provided.

  A sheet-like insulator 34 is arranged along the inner wall surface of the groove-like slot formed in the stator core 32. The stator winding 31 is made of a copper wire having a flat cross section. The surface of the copper wire is covered with a resin film layer. Therefore, in the slot, the copper wire is electrically insulated from the stator core 32 by its own film and the insulator 34.

  The stator winding 31 is configured by arranging a plurality of U-shaped conductor segments 33 according to a predetermined rule and electrically connecting the end portions of the plurality of conductor segments 33 according to a predetermined rule. Has been. In this embodiment, the electrical connection is formed by welding. In this embodiment, two U-shaped conductor segments 33a and 33b as schematically shown in FIG. 2 are used as a basic unit, and a plurality of these units are arranged to make one turn on the stator core 32. A series of windings are formed.

  The U-shaped conductor segment 33 has a turn portion 33c formed by bending a copper wire covered with a thin insulating film, and a joint portion 33e connected by welding. The turn part 33c forms a first coil end together with the skew part 33d that follows the turn part 33c. The plurality of turn portions 33c of the plurality of conductor segments 33 are regularly arranged on the rear side (the opposite pulley side) illustrated in FIG. 1 to form the first coil end group 31a. The joint portion 33e forms a second coil end together with the skew portion 33f that follows the joint portion 33e. The plurality of joint portions 33e are arranged on the front side (pulley side) illustrated in FIG. 1 to form the second coil end group 31b.

  The inclination angle θ1 of the skew portion 33d in the first coil end group 31a with respect to the axial direction is smaller than the inclination angle θ2 of the skew portion 33f in the second coil end group 31b. As a result, a larger interval is formed between the plurality of skew feeding portions 33d. Thereby, even if the joint part 33e extending straight in the axial direction is formed, the axial height of the second coil end 31b can be suppressed.

  In this embodiment, the first coil end group 31a is configured by mainly disposing a turn portion. Further, the second coil end group 31b is configured by mainly disposing a joint portion. However, these are mainly arranged with the turn part and the joint part of the basic unit. Also in the first coil end group 31a, a joint portion can be partially arranged. For example, a junction for obtaining a neutral point connection or a junction for realizing connection to the rectifier 5. Moreover, a turn part can be partially arrange | positioned in the 2nd coil end group 31b.

  A thin insulating resin 37 made of the same resin material as a second insulating resin described later is attached to the first coil end group 31a. The thin insulating resin 37 attached to the first coil end group 31a is attached to such an extent that it covers the surfaces of the plurality of conductors constituting the first coil end group 31a. As a result, in the first coil end group 31a, there is formed a cooling air passage that communicates through the first coil end group 31a from the radially inner side to the outer side. The insulating resin 37 is provided in a range from the entire first coil end group 31 a to the axial end of the stator core 32. In the first coil end group 31a, a film is partially stretched between the conductors adjacent in the radial direction, and the portions are connected to increase the rigidity. In addition, at the end of the stator core 32, the stator core 32, the insulator 34, and the conductor segment 33 are bridged and bonded together.

  As shown in FIG. 3, a thick insulating resin 36 as the first insulating resin is attached to the joint portion 33e. The insulating resin 36 is disposed so that the periphery of the tip end of the second coil end 31b is connected in an annular shape while maintaining the state where the adjacent joint portions 33e are separated from each other. The insulating resin 36 is applied with the viscosity and amount adjusted so as to form a radially extending groove 36a at the axial tip of the second coil end group 31b. The groove 36a contributes to the maintenance of the heat dissipation area. The thick insulating resin 36 can be formed by a process in which a liquid resin having a relatively high viscosity is adhered and cured, or a process in which a powder resin is adhered and melted to be cured.

  Further, a thin insulating resin 37 as a second insulating resin is attached to the second coil end 31b as a whole. The entire second coil end 31 b is covered with a thin insulating resin 37. In particular, as shown in FIG. 3, the skew portion 33 f as a conductor not covered with the insulating resin 36 in the second coil end 31 b is covered only with the insulating resin 37. The insulating resin 37 forms a space portion 37a at the base portion of the second coil end group 31b near the stator core 32.

  As shown in FIG. 4, the insulating resin 37 penetrates and adheres to the inside of the second coil end group 31b. In particular, it penetrates between a plurality of skewed portions 33f arranged in multiple layers in the radial direction and aligned in the circumferential direction. The insulating resin 37 is attached so as to stretch a film between the plurality of skew portions 33f, and bridges the plurality of skew portions 33f. The insulating resin 37 penetrates almost all between the radially adjacent conductors in the second coil end group 31b. The insulating resin 37 is attached so as to enter and stretch between the conductors adjacent in the circumferential direction in the second coil end group 31b.

  The insulating resin 37 can be formed by a process in which a liquid resin having a relatively low viscosity is attached and cured. The insulating resin 37 is applied to the second coil end group 31b with the viscosity and amount adjusted so that the bubble-shaped space 37b and the groove 37c as shown in FIG. 4 are formed. The insulating resin 37 is applied in a range from the entire second coil end group 31 b to the axial end of the stator core 32. At the end of the stator core 32, the stator core 32, the insulator 34, and the conductor segment 33 are cross-linked and bonded together.

  Between the plurality of skew portions 33f, the circumferential interval is smaller toward the inner side in the radial direction. For this reason, the insulating resin 37 substantially fills the gaps 33f as conductors both in the radial direction and in the circumferential direction on the radially inner side of the second coil end group 31b. The insulating resin 37 adheres to the skewed portion 33f leaving a large amount of space 37b because the interval between the skewed portions 33f is relatively wide outside the second coil end group 31b in the radial direction. In particular, the plurality of skewed portions 33f arranged on the outermost side as the outer layer cover the surfaces thereof, but are attached leaving a groove 37c as a space between them.

  As a result, the second coil end group 31b has a wavy surface corresponding to the skewed portion 33f on the outer side to provide a large surface area, and the inner side has a smoother surface than the outer side. In other words, the shape that the insulating resin 37 exhibits in the second coil end group 31b is a shape in which the outer side is larger than the inner side in the radial direction. In other words, a large number of deeper grooves 37c are provided on the radially outer side than on the radially inner side. In other words, the density of the insulating resin 37 is denser on the inner side in the radial direction than on the outer side. Further, the insulating resin 37 is thickly attached only to one of the two coil end groups. In this embodiment, it is more thickly attached to the second coil end group 31b including the joint portion 33e than the first coil end group 31a including the turn portion 33c. The insulating resin 37 is attached more thickly to the coil end on the front side than on the rear side.

In addition, the said embodiment is implement | achieved by the manufacturing process shown in FIG.5 and FIG.6.
FIG. 5 shows a process of attaching the insulating resin 37 to the oblique portions 33d and 33f of the first coil end group 31a and the second coil end group 31b, and FIG. 6 shows a process of attaching the insulating resin 36 to the joint 33e. ing.

  In FIG. 5, the stator 3 has a constant inclination angle Ψ with respect to the vertical axis by a jig 300 that rotates in the circumferential direction coaxially with the central axis of the stator core 32 with the first coil end group 31 a facing upward. Is retained. The inclination angle Ψ can be set to about 15 ° as shown in FIG. Thereby, it can prevent that the insulating resin 37 adheres to the front-end | tip part of the output line 310 connected to the rectifier 5. FIG.

  The insulating resin 37 is made of a liquid thermosetting resin typified by an epoxy resin, and drops a certain amount from the nozzle 302 of the dispenser 301 fixedly installed on the rotating stator 3 toward the first coil end group 31a. Is done. The liquid insulating resin 37 is adjusted to have a low viscosity.

  Thereafter, the stator 3 is placed horizontally so that the second coil end group 31b is positioned downward, and placed in an atmosphere of the curing temperature of the insulating resin 37 for a predetermined time. During this time, the insulating resin 37 passes through the slots of the stator core 32 and reaches the skewed portion 33f of the second coil end group 32b below, and the curing is completed.

  Subsequently, as shown in FIG. 6, the stator 3 heated to the curing temperature is placed horizontally so that the second coil end group 32 b faces downward, and an epoxy resin or the like is the main component. The insulating resin 36 is melted and fixed by immersing from the joint 33e to the vicinity of the joint root in the powder resin tank 302 to be melted. The powder resin tank 302 is a fluidized immersion tank that is brought into a floating state by sending dry air into the powder, so that the thickness of the insulating resin 36 is made uniform and the insulating film is stably formed. Can be formed.

  (Effect) The pulley 20 of the vehicle alternator 1 is rotationally driven by the vehicle traveling engine. An exciting current is passed through the field winding 8 of the rotor 2 via slip rings 9 and 10, and N and S poles are formed in the pole cores 71 and 72, thereby forming a rotating field. As a result, an AC voltage is induced in the stator winding 31, and this AC output is rectified by the rectifier 5 and output as DC from the output terminal 6.

  The cooling fans 11, 12 fixed to the pole cores 71, 72 take in air from the axial opening 41 of the frame 4 and blow out toward the radial opening 42. Both coil ends are cooled by this cooling air.

  Since the skew portions 33f of the second coil end 31b are fixed to each other, vibrations between the joint portions 33e at the tip are suppressed, and the short circuit of the joint portion 33e is further ensured by combining with the annular insulating resin 36 of the joint portion 33e. Can be prevented. Further, compared to the non-pulley side, the aqueous solution and solid foreign matter from the outside of the generator are more easily taken into the generator together with the cooling air from the opening 41 on the pulley side. These intruding foreign substances are relatively small and are carried toward the second coil end group 31b by the cooling fan 11, but the insulating resin 37 is provided on the inner periphery of the skewed portion 33e of the second coil end group 31b on the pulley side. Are densely attached so as to fill the surface of the skewed portion 33f as a conductor and the space between them, so that the invading foreign matter is prevented from staying inside the second coil end group 31b. Furthermore, damage to the film of the conductor itself of the skewed portion 33f of the second coil end group 31b can be prevented, and durability can be improved. Therefore, it is possible to prevent insulation failure in the plurality of skew portions 33f. Moreover, more resin adheres to the second coil end group 31b than the first coil end group 31a, but the amount of the resin is formed in the groove 37c on the radially outer side of the second coil end group 31b. Since it is limited to the extent, a sufficient surface area for heat dissipation can be secured. In particular, the excellent heat dissipation in the first coil end group 31a provides excellent heat dissipation in the entire stator winding.

  (Modification) In the first embodiment, the insulating resin 36 covering the joint portion 33e and the insulating resin 37 fixing the skew portion 33f are separately attached, but the viscosity for covering the joint portion 33e thickly, An insulating resin having both permeability to the plurality of skewed portions 33f and adhesion between the skewed portions 33f and between the conductor and the stator core 32 can be used. In this case, while reducing productivity, it is possible to similarly reduce the vibration of the coil end and improve the environmental resistance.

  In addition, the insulating resin 37 may be attached only to the second coil end group 31b so that the insulating resin 37 is not attached to the first coil end 31a. In this case, as shown in FIG. 7, the center of rotation of the jig 300 ′ is horizontal, and the insulating resin 37 may be dropped from the upper side in the radial direction of the skewed portion 33 f of the second coil end group 31 b. The subsequent steps are the same as in the first embodiment. In addition, in the attaching process of the insulating resin 36, the second coil end group 31b of the stator 3 may be immersed to a predetermined depth using a liquid resin tank instead of a powder resin tank.

  In the first embodiment, the conductor segment 33 as shown in FIG. 2 is used in order to arrange four layers of conductors in the radial direction in the slot. However, the conductor segment 33 may be constituted by a single U-shaped segment. Good. A single U-shaped segment provides two layers of conductors in the slot and provides a two layer skew arrangement in the same cross section as FIG. Such a configuration can be selected to suit the required performance.

  Further, the present invention can be applied not only to a vehicle AC generator but also to a vehicle or general-purpose rotating electrical machine having a similar air cooling structure. For example, it can be applied to an electric motor.

It is sectional drawing of the alternating current generator for vehicles of 1st embodiment of this invention. It is a perspective view of the conductor segment which forms the stator winding | coil of 1st embodiment. It is a top view which shows a part which looked at the stator of 1st embodiment from the inner peripheral side. It is a fragmentary sectional view of the coil end of a first embodiment. It is a figure which shows the insulating resin adhesion process to the skew part of the coil end of 1st embodiment. It is a figure which shows the insulating resin adhesion process to the junction part of the coil end of 1st embodiment. It is a figure which shows the insulating resin adhesion process to the skew part of the coil end of other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 AC generator for vehicles 2 Rotor 3 Stator 31 Stator winding 32 Stator core 33 Conductor segment 34 Insulator 4 Frame 41, 42 Opening 11, 12 Cooling fan 20 Pulley

Claims (4)

The first coil end group (31a) formed with a turn portion formed by the stator winding (31) extending in the axial direction from one end portion of the stator core (32) is joined to the tip portion. a plurality of joints made Te (33e) is from the second coil end group disposed (31b), the joint between the first insulating resin covering the (33e) (36), said first coil end group (31a In the method of manufacturing a stator for a vehicle alternator comprising a second insulating resin (37) covering
Thinly attaching the second insulating resin (37) to the first coil end group;
Subsequently, the first insulating resin (36) is thickly attached only in the vicinity of the plurality of joint portions (33e) of the second coil end group, and the method of manufacturing a stator for an automotive alternator is characterized. In the manufacturing method of the stator of the alternator for vehicles according to claim 1,
While the first insulating resin (36) holds state of being spaced plurality of joints to (33e), a manufacturing method of that stator of the automotive alternator according to claim which are arranged to be connected . In the manufacturing method of the stator of the alternator for vehicles according to claim 1 or 2,
The second insulating resin (37) passes through the slot of the stator core (32), and the method of manufacturing a stator for a vehicle AC generator . In the manufacturing method of the stator of the alternator for vehicles according to claim 3,
A method of manufacturing a stator for an automotive alternator , wherein the second insulating resin is adhered so that the second insulating resin covers the entire coil end group.

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