JP6512981B2 - Rectification device and rotating electric machine - Google Patents

Description

  The present invention relates to a rectifying device having a commutator, a brush, and a rectifying brush, and a rotating electrical machine including the rectifying device.

  Heretofore, an example of a technology relating to a rectifier for a brushed motor aiming to prevent sparks with a simple structure has been disclosed (see, for example, Patent Document 1). Sparks are synonymous with discharges, and are breakdowns that occur continuously in the gas between the electrodes. In the rectification device of Patent Document 1, the commutator has a plurality of segments, the plurality of segments have a main brush portion and an auxiliary brush portion, and an insulating layer is joined between the main brush portion and the auxiliary brush portion, The auxiliary brush portion maintains contact with the segment for a predetermined period after the segment is separated from the main brush portion. The pair of auxiliary brush portions are individually electrically connected to both ends of the battery through two diodes for power regeneration. The pair of auxiliary brush portions are connected by a capacitor.

JP, 2011-004582, A

  However, in the rectifying device of Patent Document 1, two diodes to be electrically connected are required between the pair of auxiliary brush portions and the battery. Assuming that the size of the diodes is constant, as the number of diodes increases, the space for accommodating the diodes increases and the number of conductive lines for electrically connecting the diodes also increases. Therefore, there is a problem that the size of the rectifier must be increased.

  In addition, a capacitor connected between the pair of auxiliary brush portions needs to have a large capacity in order to suppress the potential change of the auxiliary brush portion. Since the size of the capacitor also increases as the capacity increases, there is a problem that the size of the rectifier must be increased.

  On the other hand, dielectric breakdown occurs between the commutator and the brush when a required voltage (i.e., a potential difference) is applied. Hereinafter, the voltage at which the dielectric breakdown occurs between the commutator and the brush will be referred to as the "dielectric breakdown voltage". The brush (for example, the main brush portion and the auxiliary brush portion) is directly or indirectly electrically connected to the battery, and therefore, the supply voltage of the battery (that is, the potential difference between the plus terminal and the minus terminal) influences.

  The supply voltage of the battery may exceed the rated voltage due to factors such as overcharge and replacement with a new one. The sum of the supply voltage applied to the brush above the rated voltage and the back electromotive force generated in the commutator immediately after leaving the brush tends to exceed the breakdown voltage. In the rectifying device of Patent Document 1, since both the main brush portion and the auxiliary brush portion are electrically connected to the battery, there are cases where the potential fluctuation of the auxiliary brush portion can not be absorbed depending on the capacity of the capacitor. In this case, there is a problem that spark may occur because the sum of the supply voltage and the back electromotive force exceeds the dielectric breakdown voltage.

  The present invention has been made in view of these points, and it is an object of the present invention to provide a rectifier and a rotating electrical machine that can prevent dielectric breakdown more than ever while suppressing the physique small.

The first invention for solving the above problems is a plurality of commutator pieces (22g ) electrically connected to the winding (13a) and arranged in the circumferential direction (Ci) on the rotation shaft (11) Device including a commutator including the pair, a pair or more brushes contacting the commutator, and a pair or more commutating brushes contacting the commutator (21, 21a to 21d ) And the pair of straightening brushes for the pair of brushes, wherein the pair or more of brushes are directly or indirectly electrically connected to the power source (E) and correspond to the pair of brushes Two pairs of the commutating brushes are arranged such that one pair of the commutating brushes is on the rear side of the brush with respect to the positive rotation direction (AR1) of the commutator, and one of the brush axial directions (Ax) Placed on the side, Wherein with commutation brush is arranged on the rear side of the brush with respect to the reverse rotational direction (AR2) of the commutator, it is arranged on the other side in the axial direction of the brush, between each other pair of the rectifying brush It is characterized in that it comprises diodes (D, D1, D2) electrically connected.

  According to this configuration, the pair or more brushes are electrically connected to the power source. Although a diode is electrically connected between the pair of rectifying brushes, the rectifying brushes are not electrically connected to the power source. Since one diode may be electrically connected between the pair of rectifying brushes, the number of diodes can be reduced, and the number of conductive lines can also be reduced. Therefore, the size of the rectifier can be reduced.

In addition, since the commutator pieces immediately after the brushes are separated come into contact with one side of the pair of rectifying brushes, the voltage changes by the voltage drop of the diode electrically connected between the pair of rectifying brushes. . Since the potential difference between the voltage of the commutator piece and the voltage of the power supply is less than the dielectric breakdown voltage, dielectric breakdown can be prevented more than in the past.
Furthermore, the flow straightening brush and the brush are arranged offset in the axial direction. Therefore, since the straightening brush can be designed in shape, size, etc. independently of the brush, the degree of freedom in design is enhanced.
In addition, two pairs of flow straightening brushes are provided for one pair of brushes. The two pairs of commutating brushes corresponding to the pair of brushes have one pair of commutating brushes disposed on the rear side of the brush with respect to the forward rotation direction of the commutator, and the other pair of commutating brushes is the reverse of the commutator It is disposed on the rear side of the brush with respect to the rotation direction. Therefore, even with the rotating electrical machine in which the rotating shaft rotates in both directions, it is possible to prevent the dielectric breakdown more than ever while suppressing the physique to be small.

  A second aspect of the invention relates to a rectifying device (20) according to any one of claims 1 to 7, a rotating shaft (11) on which the commutator is provided, and the rotating shaft in a rotating electrical machine (10). It has a rotor (13) fixed directly or indirectly, and a stator (14) provided via the rotor and a gap (G).

  According to this configuration, it is possible to provide a rotating electrical machine capable of preventing dielectric breakdown more than ever while suppressing the physique to be small.

  The number of phases of the winding including the coil is arbitrary as long as it has three or more phases. The “power source” may be a power source (for example, a battery or a commercial power source) itself, and may further include a power conversion device that converts and outputs power. The “rotating electric machine” is optional as long as it is a device having a rotating member (for example, a shaft, a shaft, etc.). For example, a generator, an electric motor, a motor generator, etc. correspond. The generator includes the case where the motor generator is a generator function machine, and the motor includes the case where the motor generator is an electric motor. The “rotor” is formed in a circular shape (including an annular shape, a cylindrical shape, and the like).

It is a partial cross section figure which shows the structural example of a rotary electric machine typically. It is a perspective view which shows the structural example of a rectification device typically. It is a circuit diagram showing typically the example of composition of a rectifier. It is the circumferential direction expanded view which shows the 1st example of arrangement | positioning of a brush, a rectification | straightening brush, and a commutator piece. It is a time-chart figure which shows the voltage change of the commutator piece in a 1st example of arrangement | positioning. It is the circumferential direction expanded view which shows the 2nd example of arrangement | positioning of a brush, a rectification | straightening brush, and a commutator piece. It is a time-chart figure which shows the voltage change of the commutator piece in a 2nd example of arrangement | positioning. It is the circumferential direction expanded view which shows the 3rd example of arrangement | positioning of a brush, a rectification brush, and a commutator piece. It is the circumferential direction expanded view which shows the 4th example of arrangement | positioning of a brush, a rectification | straightening brush, and a commutator piece. It is the circumferential direction expanded view which shows the 5th example of arrangement | positioning of a brush, a rectification | straightening brush, and a commutator piece. It is the circumferential direction expanded view which shows the 6th example of arrangement | positioning of a brush, a rectification brush, and a commutator piece.

  Hereinafter, an embodiment for carrying out the present invention will be described based on the drawings. In addition, unless otherwise specified, in the case of "connect" means to electrically connect. The figures illustrate the elements that are necessary to illustrate the invention and may not depict all actual elements. When saying directions such as top, bottom, left, and right, the description in the drawings is used as a reference.

  The alphanumeric serial code is abbreviated using the symbol "~". For example, "coils L1 to L6" mean "coils L1, L2, L3, L4, L5, L6". The alphabet of the code means different elements in upper and lower case. For example, the commutator 22A and the commutator piece 22a shown in FIG. 4 are separate elements. There is no limitation on the method of fixing the members. The magnetic material is mainly a soft magnetic material, but the material, the configuration, etc. may be any, provided that the magnetic flux flows.

[Form 1 of reference ]
Reference Embodiment 1 will be described with reference to FIGS. 1 to 7. The rotary electric machine 10 shown in FIG. 1 is an example of an inner rotor type. The rotary electric machine 10 has a rotary shaft 11, a rotor 13, a stator 14, a rectifying device 20 and the like in a housing 12.

  The housing 12 is also referred to as a “frame” or a “housing”, and may be formed in any shape as long as the above-described elements can be accommodated. Although not shown, one or more of a pulley, a rotation angle detection sensor, a semiconductor element, etc. may be accommodated.

  The rotating shaft 11, which is also referred to as a "shaft", is rotatably supported by the housing 12 via a bearing (not shown). The rotor 13 is fixed to the rotating shaft 11 directly or indirectly. That is, the rotating shaft 11 and the rotor 13 rotate integrally. The rotor 13 has a winding 13a, a rotor core 13b, and the like. The winding 13a is a winding of three or more phases, and is wound around the rotor core 13b. The rotor core 13b is mainly formed of a magnetic material.

  The stator 14 is fixed to the housing 12. The configuration of the stator 14 is optional and may include a plurality of magnets. For example, the radial end faces facing the rotor 13 are arranged circumferentially so that the polarities of the N pole and the S pole alternate. A gap G is provided between the stator 14 and the rotor 13 in the radial direction Ra.

  The rectifying device 20 includes a pair or more of rectifying brushes 21, a commutator 22, a pair of more than brushes 23, a diode D, and the like. The flow straightening brush 21 and the brush 23 are respectively accommodated in insulating brush holders (not shown). The brush holder is provided on the housing 12 and is biased by an elastic member (for example, a spring, rubber or the like) so that the rectifying brush 21 and the brush 23 contact the commutator 22 respectively. The commutator 22 is provided on the rotating shaft 11 as shown in FIG. A configuration example of the commutator 22 will be described later (see FIG. 2, FIG. 3 and the like).

  For example, the straightening brush 21a and the straightening brush 21b correspond to the pair of straightening brushes 21. The diode D is connected between the rectifying brush 21a and the rectifying brush 21b such that the tip end side (that is, the rectifying brush 21a side) of the rotational direction AR is a cathode. The pair of brushes 23 correspond to, for example, the positive electrode brush 23 a and the negative electrode brush 23 b. The positive electrode brush 23 a is connected to the positive terminal of the power source E, and the negative electrode brush 23 b is connected to the negative terminal of the power source E. The power source E is optional as long as it can supply power for operating (i.e., rotating, stopping, etc.) the rotary electric machine 10, and, for example, a secondary battery, a fuel cell, a solar cell or the like corresponds. In order to charge the electric power generated by the rotating electrical machine 10 by a regenerative brake or the like, a secondary battery is desirable.

  Between the rotating electrical machine 10 (specifically, the brush 23) and the power source E, a power conversion device INV indicated by a two-dot chain line may be interposed. The power conversion device INV performs control to convert the power supplied from the power source E and output it to the rotating electrical machine 10, for example, by PWM (Pulse Width Modulation). The power converter INV corresponds to, for example, an electronic control unit (ECU) or a computer. The power conversion control performed by the power conversion device INV can control the rotational speed, torque, and the like of the rotating shaft 11.

  The commutator 22 shown in FIG. 2 is fixed to the rotating shaft 11 that rotates in the rotation direction AR. The commutator 22 has a plurality of commutator pieces 22 a arranged in the circumferential direction Ci as illustrated. The number of commutator segments 22a constituting the commutator 22 may be set arbitrarily, and FIG. 3 shows an example in which six commutator segments 22a are set. Insulation is secured between the commutator pieces 22a adjacent in the circumferential direction Ci. For example, as shown in FIG. 3, an air gap may be provided between the commutator segments 22a, and an insulating member may be filled between the commutator segments 22a.

  The pair of commutating brushes 21 is disposed on the rear side of the pair of brushes 23 with respect to the rotation direction AR (right rotation in FIG. 2) of the commutator 22A. That is, the rectifying brush 21a is disposed on the rear side (left side in FIG. 2) of the corresponding positive electrode brush 23a with respect to the rotational direction AR of the commutator 22A. Similarly, the rectifying brush 21b is disposed on the rear side (left side in FIG. 2) of the corresponding negative electrode brush 23b with respect to the rotation direction AR of the commutator 22A.

  Moreover, between the commutator pieces 22a adjacent to each other in the circumferential direction Ci are connected by a winding 13a indicated by an alternate long and short dash line in FIG. The number of coils included in the winding 13a may be set arbitrarily, and FIG. 3 shows an example set by six coils L1 to L6. Each coil of the coils L1 to L6 is connected between the commutator pieces 22a adjacent in the circumferential direction Ci. In FIG. 3, the power converter INV shown in FIG. 1 and the rotary shaft 11 etc. are not shown.

  The rectifying action of the above-described rectifying device 20 will be described with reference to FIGS. 4 to 7. FIGS. 4 and 5 show an example in which the positive electrode brush 23a is separated from the commutator piece 22a, and FIGS. 6 and 7 show an example in which the negative electrode brush 23b is separated from the commutator piece 22a. For convenience of explanation, in FIGS. 4 and 6, hatching lines are attached to the commutator pieces 22a separated from the positive electrode brush 23a and the negative electrode brush 23b which have been in contact, and the illustration of the coil L6 is omitted. The diode D1 shown in FIGS. 4 and 6 corresponds to the diode D shown in FIGS.

  The hatched commutator 22a is hereinafter referred to as "disengaged commutator 22ax" for the sake of convenience. The potential of the negative terminal of the power source E shown in FIGS. 1 and 3 is referred to as a reference (hereinafter simply referred to as “reference potential”), and is shown as 0 [V] in FIGS. 5 and 7. However, the reference potential is not limited to the same potential as the ground potential (so-called ground). Therefore, the commutator piece voltage V22a of the separation commutator piece 22ax is a potential difference between it and the reference potential. In addition, although the voltage drop by each resistance of a brush, a rectification brush, and a conductive wire arises strictly, since these elements are not different from before, they are not considered below. The conductive wire corresponds to a "connecting wire" connecting elements to each other, including the case of using a part of the winding.

  In FIG. 4, when the positive electrode brush 23a is separated from the separation commutator piece 22ax, there is a possibility that an arc discharge A1 (that is, dielectric breakdown) indicated by an arrow may occur due to the back electromotive force generated in the coil L2. That is, the dielectric breakdown voltage Vth is generated between the positive electrode brush 23a and the separation commutator piece 22ax. The commutator piece voltage V22a changes, for example, as shown in FIG.

  In FIG. 5, the commutator-piece voltage V22a is the same as the power supply voltage Ve (that is, the potential of the positive terminal of the power source E) until time t11 when the separation rectifier piece 22ax is in contact with the positive electrode brush 23a. When the separation commutator piece 22ax is separated from the positive electrode brush 23a, a back electromotive force is generated by the coil L2, and a voltage V13 (where V13 <0) indicated by a two-dot chain line can be obtained. The voltage V13 is lower than 0 [V] in addition to the back electromotive force by the coil L2, the negative terminal of the power source E via the rectifying brush 21a, the diode D1, the rectifying brush 21b, the commutator 22a, and the negative electrode brush 23b. This is because it is connected to (that is, 0 [V] of the reference potential). When the voltage V15 which is a potential difference between the power supply voltage Ve and the voltage V13 becomes equal to or higher than the dielectric breakdown voltage Vth (V15 ≧ Vth), an arc discharge A1 is generated.

  Here, as described above, the separated commutator piece 22ax when separated from the positive electrode brush 23a is the negative terminal of the power source E via the rectifying brush 21a, the diode D1, the rectifying brush 21b, the commutator piece 22a, and the negative electrode brush 23b. Connected to That is, the commutator piece voltage V22a becomes a voltage V12 (for example, -0.7 [V]) lower than 0 [V] (that is, the reference potential) by the voltage drop of the diode D1. The voltage V12 is also the cathode side voltage of the diode D1. Therefore, the voltage V14 which is a potential difference between the power supply voltage Ve and the voltage V12 becomes less than the dielectric breakdown voltage Vth (V14 <Vth), and the occurrence of the arc discharge A1 can be suppressed. The voltage V12 is maintained independently of the fluctuation of the power supply voltage Ve, so that the situation where the voltage V14 becomes higher than the dielectric breakdown voltage Vth can be suppressed.

  After that, at time t12 when the back electromotive force by the coil L2 is settled, the commutated piece voltage V22a becomes the voltage V11. The voltage V11 is a partial pressure applied to the coil L2 in the coils L1 to L6 shown in FIG. At time t13 when the commutator 22 fixed to the rotating shaft 11 makes one rotation and the separated commutating piece 22ax contacts the positive electrode brush 23a again, the same as the power supply voltage Ve.

  In FIG. 6, when the negative electrode brush 23b is separated from the separation commutator piece 22ax, there is a possibility that an arc discharge A2 (that is, dielectric breakdown) indicated by an arrow may occur due to the back electromotive force generated in the coil L4. That is, the dielectric breakdown voltage Vth is generated between the negative electrode brush 23b and the separation commutator piece 22ax. The commutator piece voltage V22a changes, for example, as shown in FIG.

  In FIG. 7, the commutator-piece voltage V22a is the same as 0 [V] (that is, the reference potential) until time t21 when the separation commutator piece 22ax is in contact with the negative electrode brush 23b. When the separation commutator piece 22ax is separated from the negative electrode brush 23b, a back electromotive force is generated by the coil L4, and a voltage V21 (V21> Ve) indicated by a two-dot chain line can be obtained. The voltage V21 exceeds the power supply voltage Ve because, in addition to the back electromotive force by the coil L4, the separated commutator piece 22ax is supplied with electric power via the rectifying brush 21b, the diode D1, the rectifying brush 21a, the commutating piece 22a, and the positive electrode brush 23a. It is because it is connected to the positive terminal of the source E. When the voltage V25 which is a potential difference between 0 [V] and the voltage V21 becomes equal to or higher than the dielectric breakdown voltage Vth (V25 ≧ Vth), an arc discharge A2 is generated.

  Here, as described above, the separated commutator piece 22ax when separated from the negative electrode brush 23b is the positive terminal of the power source E through the rectifying brush 21b, the diode D1, the rectifying brush 21a, the commutator piece 22a, and the positive electrode brush 23a. Connected to That is, the commutator piece voltage V22a becomes a voltage V22 (for example, 12.7 [V]) higher than the power supply voltage Ve (that is, the potential of the positive terminal of the power source E) by the voltage drop of the diode D1. The voltage V22 is also a cathode side voltage of the diode D1. Therefore, the voltage V24 which is a potential difference between 0 [V] and the voltage V22 becomes less than the dielectric breakdown voltage Vth (V24 <Vth), and the occurrence of the arc discharge A2 can be suppressed. The voltage V22 is maintained regardless of the fluctuation of the power supply voltage Ve, so that the situation where the voltage V24 becomes higher than the dielectric breakdown voltage Vth can be suppressed.

  After that, at time t22 when the back electromotive force by the coil L4 is settled, the commutated piece voltage V22a becomes the voltage V23. The voltage V23 is a partial pressure applied to the coil L4 in the coils L1 to L6 shown in FIG. At time t23 when the commutator 22 fixed to the rotating shaft 11 makes one rotation, and the separated commutating piece 22ax comes in contact with the negative electrode brush 23b again, it becomes the same as 0 [V].

According to the first above-mentioned reference, it is possible to obtain the respective functions and effects described below.

  (1) In the rectifying device 20, the pair of brushes 23 (i.e., the positive brush 23a and the negative brush 23b) are connected to the power source E, and the pair of rectifying brushes 21 (i.e., the rectifying brushes 21a and 21b) are in the rotating direction of the commutator 22A. The diode D1 is disposed on the rear side of the brush 23 with respect to the AR and connected between the pair of rectifying brushes 21 (see FIGS. 1 to 4 and 6). According to this configuration, the pair of brushes 23 is connected to the power source E. Although the diode D 1 is connected between the pair of rectifying brushes 21, the rectifying brush 21 is not connected to the power source E. Since one diode D1 may be connected between the pair of rectifying brushes 21, the number of diodes D1 can be reduced, and the number of conductive lines can also be reduced. Therefore, the physique of the rectifier 20 can be reduced. Although not shown, two or more pairs of brushes 23 may be connected to the power source E, and in this case, the same effect can be obtained.

  Further, one side (a straightening brush 21a in FIG. 4 and a straightening brush 21b in FIG. 6) of the straightening brush 21 forming a pair is in contact with the commutator piece 22a immediately after the brush 23 is separated (that is, the separated commutating piece 22ax). Thus, the voltages V12 and V22 change by the voltage drop of the diode D1 electrically connected between the pair of rectifying brushes 21a and 21b. The potential difference between the voltages V12 and V22 of the rectifier piece 22a and the power supply voltage Ve of the power source E is less than the dielectric breakdown voltage Vth (see FIGS. 5 and 7). Thus, the voltages V12 and V22 which are the cathode side voltages of the diode D1 are increased, and the dielectric breakdown can be prevented more than in the prior art.

  (8) The rotating electrical machine 10 includes the rectifying device 20, the rotating shaft 11 provided with the commutator 22A, the rotor 13 fixed directly or indirectly to the rotating shaft 11, the rotor 13 and the gap G. And the stator 14 provided (see FIG. 1). According to this configuration, it is possible to provide the rotary electric machine 10 capable of preventing the dielectric breakdown more than ever while suppressing the physique to be small.

  (9) The rotor 13 of the rotary electric machine 10 is configured to be provided with the winding 13a including the coils L1 to L6 (see FIGS. 1 and 3). According to this configuration, even with the rotary electric machine 10 having the rotor 13 provided with the winding 13a, it is possible to provide the rotary electric machine 10 capable of preventing the dielectric breakdown more than ever while suppressing the physique small.

[Form 2 of reference ]
Reference Embodiment 2 will be described with reference to FIG. Note for ease of illustration and description, unless otherwise specified, the same elements and units used in Reference Embodiment 1 will not be described are denoted by the same reference numerals. Accordingly, it will be mainly described differences from the Embodiment 1 of reference.

  FIG. 8 shows a commutator 22B which is an example of the commutator 22 and is a modification of the commutator 22A. Like the commutator 22A, the commutator 22B includes a plurality of commutator pieces 22b. The commutator 22B differs from the commutator 22A in the shape of the outer peripheral surface of each commutator piece 22b.

  Each commutator piece 22b of the commutator 22B has a first contact portion 22d and a second contact portion 22c. The first contact portion 22d is a portion that contacts the brush 23 (that is, the positive electrode brush 23a and the negative electrode brush 23b), and the width in the circumferential direction Ci is a first contact width W1. The second contact portion 22c is a portion in contact with the rectifying brush 21 and has a width in the circumferential direction Ci as a second contact width W2. The second contact width W2 may be set to be different from the first contact width W1, and as illustrated, the second contact width W2 may be set smaller than the first contact width W1 (W2 <W1).

  The flow straightening brushes 21 (i.e., the flow straightening brushes 21a and 21b) are formed in a shape that avoids simultaneous contact with the plurality of commutator pieces 22b. In the configuration example of FIG. 8, assuming that the width in the circumferential direction Ci of the rectifying brushes 21 a and 21 b is the circumferential width WR and the interval between the second contact portions 22 c adjacent in the circumferential direction Ci is the mutual width WM, the circumferential width WR is set smaller than the mutual width WM (WR <WM).

  The rectifying brush 21a is disposed on the rear side (left side in FIG. 8) of the corresponding positive electrode brush 23a with respect to the rotational direction AR of the commutator 22B. The front end face of the straightening brush 21a and the rear end face of the positive electrode brush 23a may be aligned with the illustrated boundary line B1.

  The rectifying brush 21b is disposed on the rear side (left side in FIG. 8) of the corresponding negative electrode brush 23b with respect to the rotation direction AR of the commutator 22B. The front end face of the straightening brush 21c and the rear end face of the negative electrode brush 23b may be aligned with the illustrated boundary line B2.

Brush 23 shown in FIG. 8 (i.e. the positive electrode brushes 23a and negative brushes 23b) and the rectifying brush 21 (i.e. rectified brushes 21a, 21b) is a reference of the first position compared (FIG. 4, FIG. 6 reference) is different. That is, the brushes 23 and the flow straightening brushes 21 are disposed at different positions in the axial direction Ax. In other words, the brush 23 contacts only the first contact portion 22d of the commutator bar 22b, and the rectifying brush 21 contacts only the second contact portion 22c of the commutator bar 22b.

  Also in the above-described configuration, when the positive electrode brush 23a is separated from the first contact portion 22d (the commutator bar 22b corresponding to the separated commutator bar 22ax), the potential changes as shown in FIG. When the negative electrode brush 23b is separated from the above, the potential changes as shown in FIG.

According to the second of the above-mentioned reference, in addition to the operational effect as in Reference Embodiment 1, it is possible to obtain the respective actions and effects described below.

  (2) The flow straightening brushes 21 (i.e., the flow straightening brushes 21a and 21b) and the brushes 23 (i.e., the positive polarity brush 23a and the negative polarity brush 23b) are arranged offset in the axial direction Ax (see FIG. 8). According to this configuration, since the shape and size of the rectifying brush 21 can be designed independently of the brush 23, the degree of freedom in design is enhanced.

  (3) The commutator piece 22b is configured to be provided such that the first contact width W1 in the circumferential direction Ci in contact with the brush 23 and the second contact width W2 in the circumferential direction Ci in contact with the rectifying brush 21 are different. (See Figure 8). According to this configuration, the timing of contact with the brush 23 and the timing of contact with the rectifying brush 21 can be finely designed. Therefore, the degree of freedom in design is enhanced, and the occurrence of a short circuit current can be reliably prevented, and arc discharges A1 and A2 (see FIGS. 4 and 6) due to dielectric breakdown can be suppressed.

  (4) The flow straightening brushes 21a and 21b are formed in such a shape as to avoid simultaneous contact with the plurality of commutator pieces 22b (specifically, the second contact portions 22c) (see FIG. 8). . According to this configuration, since the rectifying brush 21 does not contact with the plurality of commutator segments 22b simultaneously, the generation of the short circuit current can be reliably prevented.

  (5) The commutator 22B has a first contact portion 22d in contact with the brush 23 and a second contact portion 22c in contact with the flow straightening brush 21. The circumferential width WR of the flow straightening brush 21 is adjacent to the circumferential direction Ci The configuration is set to be smaller than the mutual width WM of the two contact portions 22c (WR <WM; see FIG. 8). According to this configuration, since the circumferential width WR is smaller than the mutual width WM, the rectifying brush 21 does not contact with the plurality of commutator pieces 22b (specifically, the second contact portions 22c) simultaneously. Therefore, the generation of the short circuit current can be reliably prevented.

[Form 3 of reference ]
The reference mode 3 will be described with reference to FIG. In addition, in order to simplify the illustration and the description, unless otherwise specified, the same elements as the elements used in the reference embodiments 1 and 2 will be assigned the same reference numerals and descriptions thereof will be omitted. Therefore, points different from the reference modes 1 and 2 will be mainly described.

  FIG. 9 shows a commutator 22C which is an example of the commutator 22 and is a modification of the commutator 22A. The commutator 22C includes a plurality of commutator segments 22e, a plurality of independent commutator segments 22f, and the like. The number of commutator segments 22e and the number of the plurality of independent commutator segments 22f may be set arbitrarily. In the present embodiment, the number of commutator segments 22e matches the number of independent commutator segments 22f.

  The commutator piece 22e has a first contact portion 22d and a second contact portion 22c, similarly to the commutator piece 22b shown in FIG. The commutator piece 22e is different in shape from the commutator piece 22b shown in FIG. 8 and is formed, for example, in an L shape. The width of the commutator piece 22e in the circumferential direction Ci applied to the first contact portion 22d is referred to as a first contact width W3, and the width of the circumferential direction Ci applied to the second contact portion 22c is referred to as a second contact width W4. The second contact width W4 may be set to be different from the first contact width W3, and as illustrated, the second contact width W4 may be set smaller than the first contact width W3 (W4 <W3).

  The independent commutator piece 22f is disposed at a position corresponding to the second contact portion 22c of the commutator piece 22e, and is not connected to other elements including the winding 13a. Therefore, the independent commutator segments 22f have a floating potential when they do not contact the rectifying brushes 21a and 21b.

  Also in the configuration described above, when the positive electrode brush 23a is separated from the first contact site 22d (the commutator tab 22e corresponding to the separated commutator tab 22ax), the potential changes as shown in FIG. When the negative electrode brush 23b is separated from the above, the potential changes as shown in FIG.

According to Reference Embodiment 3 described above, in addition to the operational effect as in Reference mode 1, it is possible to obtain the advantageous effects described below.

  (6) The commutator 22C includes the independent commutator segments 22f that have a floating potential when they do not contact the rectifying brush 21 (see FIG. 9). According to this configuration, since the independent commutator piece 22f is not connected to the winding 13a, the floating potential state is maintained when it does not contact the brush 23 or the rectifying brush 21. Therefore, the voltage does not reach the dielectric breakdown voltage Vth or more between the brush 23 and the rectifying brush 21, and arc discharges A1 and A2 (see FIGS. 4 and 6) due to dielectric breakdown can be suppressed.

[Form 4 of reference ]
Embodiment 4 Reference is a modification of Reference Embodiment 2 (see FIG. 8) will be described with reference to FIG. 10. Note for ease of illustration and description, unless otherwise specified, the same elements and units used in Reference Embodiment 1-3 will not be described are denoted by the same reference numerals. Therefore, points different from the reference embodiments 1 to 3 will be mainly described.

  The configuration shown in FIG. 10 is different from the configuration shown in FIG. 8 in that rectifying brushes 21c and 21d and a diode D2 are further provided. The straightening brushes 21c and 21d correspond to the pair of straightening brushes 21 similarly to the straightening brushes 21a and 21b. The flow straightening brushes 21a to 21d are arranged offset from the brush 23 in the axial direction Ax. The forward rotation direction AR1 shown in FIG. 10 corresponds to the rotation direction AR shown in FIG. The reverse rotation direction AR2 is reverse to the normal rotation direction AR1.

  The rectifying brush 21c is disposed on the rear side (right side in FIG. 10) of the corresponding positive electrode brush 23a with respect to the reverse rotation direction AR2 of the commutator 22B. The front end face of the straightening brush 21c and the rear end face of the positive electrode brush 23a may be aligned with the illustrated boundary line B3.

  The rectifying brush 21d is disposed on the rear side (right side in FIG. 10) of the corresponding negative electrode brush 23b with respect to the reverse rotation direction AR2 of the commutator 22B. The front end face of the straightening brush 21d and the rear end face of the negative brush 23b may be aligned with the illustrated boundary line B4.

  Assuming that the width in the circumferential direction Ci of the rectifying brushes 21c and 21d is the circumferential width WR, and the distance between the second contact portions 22c adjacent in the circumferential direction Ci is the mutual width WM, the circumferential width WR is greater than the mutual width WM Also set smaller (WR <WM).

  The diode D2 corresponds to the diode D shown in FIGS. The diode D2 is connected between the rectifying brush 21c and the rectifying brush 21d such that the tip end side (that is, the rectifying brush 21d side) of the rotation direction AR2 is a cathode. In other words, the diodes D1 and D2 are connected in opposite directions to each other as illustrated.

When the commutator 22B with rotation of the rotary shaft 11 is rotated in the normal rotation direction AR1 is in the same manner as in Reference Embodiment 2, the rectifying brush 21a, using 21b and the diode D1. In this case, when the positive electrode brush 23a is separated from the first contact portion 22d (the commutator bar 22b corresponding to the separated commutator bar 22ax), the potential changes as shown in FIG. When the brush 23b is separated, the potential changes as shown in FIG.

  When the commutator 22B rotates in the reverse rotation direction AR2 with the rotation of the rotating shaft 11, the rectifying brushes 21c and 21d and the diode D2 are used. Also in this case, when the positive electrode brush 23a is separated from the first contact portion 22d (the commutator bar 22b corresponding to the separated commutator bar 22ax), the potential changes as shown in FIG. When the brush 23b is separated, the potential changes as shown in FIG.

According to Reference Mode 4 described above, in addition to the operational effect as in Reference mode 1, it is possible to obtain the advantageous effects described below.

  (7) Two pairs of flow straightening brushes 21 (i.e. flow straightening brushes 21a and 21b and flow straightening brushes 21c and 21d) are provided for the pair of brushes 23. The two pairs of commutating brushes 21 have one pair of commutating brushes 21 (i.e., commutating brushes 21a and 21b) disposed on the rear side of the brush 23 with respect to the forward rotation direction AR1 of the commutator 22B, and the other pair The straightening brush 21 (i.e., straightening brushes 21c and 21d) is disposed on the rear side of the brush 23 with respect to the reverse rotation direction AR2 of the commutator 22B (see FIG. 10). According to this configuration, even with the rotary electric machine 10 in which the rotary shaft 11 rotates in both directions, it is possible to prevent the dielectric breakdown more than ever while suppressing the physique to be small.

Embodiment
Embodiment is a modification of Reference Embodiment 3 (see FIG. 9) will be described with reference to FIG. 11. Note for ease of illustration and description, unless otherwise specified, the same elements and units used in Reference Embodiment 1-4 will not be described are denoted by the same reference numerals. Therefore, points different from the reference embodiments 1 to 4 will be mainly described.

  The configuration shown in FIG. 11 is different from the configuration shown in FIG. 9 in the following points. First, it further includes rectifying brushes 21c and 21d and a diode D2. Second, in addition to the independent commutator pieces 22f provided on one side (the upper side in FIG. 11) of the axial direction Ax, the independent commutator pieces 22h provided on the other side (the lower side in FIG. 11) of the axial direction Ax Prepare. Third, as the independent commutator segments 22h are provided, the shapes of the plurality of commutator segments 22g are changed.

  FIG. 11 shows a commutator 22D which is an example of the commutator 22 and is a modification of the commutator 22C. The commutator 22D includes a plurality of commutator segments 22g, a plurality of independent commutator segments 22f, a plurality of independent commutator segments 22h, and the like. The number of commutator segments 22g, the number of the plurality of independent commutator segments 22f, and the number of the plurality of independent commutator segments 22h may be set arbitrarily. In the present embodiment, the numbers of the commutator segments 22e, the independent commutator segments 22f, and the independent commutator segments 22h are the same.

  The commutator bar 22g has a first contact portion 22d, a second contact portion 22c provided on both sides of the first contact portion 22d in the axial direction Ax, and the like. The second contact portions 22c provided on one side of the axial direction Ax can be in contact with the rectifying brushes 21a and 21b. The second contact portions 22c provided on the other side in the axial direction Ax can be in contact with the rectifying brushes 21c and 21d.

  The flow straightening brushes 21c and 21d are disposed at positions shifted in the axial direction Ax with respect to the flow straightening brushes 21a and 21b as well as the brush 23 (that is, the positive polarity brush 23a and the negative polarity brush 23b). The rectifying brushes 21a and 21b are provided at positions corresponding to the independent commutator pieces 22f disposed on one side in the axial direction Ax. The flow straightening brushes 21c and 21d are provided at positions corresponding to the independent commutator segments 22h provided on the other side in the axial direction Ax.

  The independent commutator segments 22h, like the independent commutator segments 22f, are not connected to other elements including the winding 13a. Therefore, the independent commutator segments 22h have a floating potential when they do not contact the rectifying brushes 21c and 21d.

When the commutator 22D with rotation of the rotary shaft 11 is rotated in the normal rotation direction AR1 is in the same manner as in Reference Embodiment 2, the rectifying brush 21a, using 21b and the diode D1. In this case, when the positive electrode brush 23a is separated from the first contact portion 22d (the commutator bar 22g corresponding to the separated commutator bar 22ax), the potential changes as shown in FIG. When the brush 23b is separated, the potential changes as shown in FIG.

  When the commutator 22D rotates in the reverse rotation direction AR2 with the rotation of the rotating shaft 11, the rectifying brushes 21c and 21d and the diode D2 are used. Also in this case, when the positive electrode brush 23a is separated from the first contact portion 22d (the commutator bar 22g corresponding to the separated commutator bar 22ax), the potential changes as shown in FIG. When the brush 23b is separated, the potential changes as shown in FIG.

According to the embodiment described above, it is possible to obtain the advantageous effects as in Reference form 1,2,4. In addition, since the diode D1 and the diode D2 are disposed while being displaced in the axial direction Ax, it is possible to avoid concentration of components, wires, and the like at one place.

Other Embodiments
Although the embodiments for carrying out the present invention have been described above in accordance with the reference embodiments 1 to 4 and the embodiment , the present invention is not limited to the embodiments. In other words, various modifications can be made without departing from the scope of the present invention. For example, the following embodiments may be realized.

In Reference Embodiment 1-3 described above, and configured to include a pair of rectifying brush 21 and a pair of brushes 23 (see FIGS. 2 to 4, 6, 8, 9). Instead of this configuration, two or more pairs of rectifying brushes 21 may be provided, or two or more pairs of brushes 23 may be provided. Only the logarithms of the straightening brush 21 and the brush 23 are different, and the characteristics shown in FIG. 5 and FIG. 7 can be obtained. Therefore, the same effects as those of the reference embodiments 1 to 4 and the embodiment can be obtained.

In the above-described reference embodiments 1 to 4 and the embodiment , the diode D (D1, D2) is connected between the pair of rectifying brushes 21 (rectifying brushes 21a, 21b and rectifying brushes 21c, 21d) 1 to 4, 6 and 8 to 11). Instead of this form, a semiconductor element (for example, a transistor, a thyristor or the like) having a rectifying function may be connected, or a resistor that causes a potential difference corresponding to the voltage between the terminals of the diode D may be connected. Even in these cases, since the characteristics shown in FIG. 5 and FIG. 7 can be obtained, the same effects as in the reference embodiments 1 to 4 and the embodiment can be obtained.

In the reference embodiments 1 to 4 and the embodiment described above, the stator 14 is configured by arranging a plurality of magnets in the circumferential direction (see FIG. 1). Instead of this configuration, a stator core mainly formed of a magnetic material, a stator winding wound around the stator core, or the like may be provided. Furthermore, a magnet may be embedded in the stator core. Only the configuration of the stator 14 is different, and the characteristics shown in FIG. 5 and FIG. 7 can be obtained, so the same effects as those of the reference embodiments 1 to 4 and the embodiment can be obtained.

In the reference embodiments 1 to 4 and the embodiment described above, the power conversion device INV is provided separately from the rotary electric machine 10 (see FIG. 1). Instead of this form, the power conversion device INV may be integrated with the rotary electric machine 10. That is, the power converter INV may be provided inside the rotary electric machine 10, or the power converter INV may be fixed outside the rotary electric machine 10. Only the form of the power conversion device INV is different, and the characteristics shown in FIG. 5 and FIG. 7 can be obtained. Therefore, the same function and effect as the reference embodiments 1 to 4 and the embodiment can be obtained.

In the reference embodiments 1 to 4 and the embodiment described above, the configuration is applied to the inner rotor type rotating electrical machine 10 (see FIG. 1). Instead of this configuration, the configuration may be applied to an outer rotor type rotating electrical machine 10. Only the positions of the rotor 13 and the stator 14 are different, and the characteristics shown in FIG. 5 and FIG. 7 can be obtained, so the same effects as those of the reference embodiments 1 to 4 and the embodiment can be obtained.

DESCRIPTION OF SYMBOLS 10 rotary electric machine 11 Rotation shaft 13a Winding wire 20 Rectification device 21 (21a-21d) Rectifying brush 22 (22A-22D) Commutator 22a, 22b, 22e, 22g Commutator piece 23 Brush 23a Positive electrode brush 23b Negative electrode brush D (D1, D D2) Diode

Claims (7)

A commutator (22) including a plurality of commutator pieces (22g ) electrically connected to the winding (13a) and arranged in the circumferential direction (Ci) on the rotation shaft (11);
A pair of brushes (23) in contact with the commutator;
In a rectifying device (20) having a pair of rectifying brushes (21, 21a to 21d ) in contact with the commutator,
Comprising a pair of said commutating brushes for a pair of said brushes,
The pair or more of the brushes are electrically connected directly or indirectly to the power source (E),
The two pairs of commutating brushes corresponding to the pair of brushes have one pair of the commutating brushes disposed on the rear side of the brush with respect to the positive rotation direction (AR1) of the commutator, and The other pair of the commutating brushes disposed on one side of the axial direction (Ax) are disposed on the rear side of the brush with respect to the reverse rotation direction (AR2) of the commutator, and the axial direction of the brush Placed on the other side,
A rectifying device comprising a diode (D, D1, D2) electrically connected between a pair of the rectifying brushes. The commutator pieces are provided such that a first circumferential contact width (W1, W3) in contact with the brush and a second circumferential contact width (W2, W4) in contact with the rectifying brush are different. rectifier device according to claim 1, characterized in that. The rectifying device according to claim 1 or 2, wherein the rectifying brush is formed in a shape that avoids simultaneous contact with a plurality of the commutator pieces. The commutator includes a first contact portion (22d) in contact with the brush and a second contact portion (22c) in contact with the rectifying brush.
The rectifying brush circumferential width (WR) is any one of claims 1 to 3, characterized in that it is smaller than the circumferentially adjacent second contact portion of mutual width (WM) The rectifier as described in. The rectifier according to any one of claims 1 to 4 , wherein the commutator includes an independent commutator piece (22f, 22h) which has a floating potential when not contacting the rectifying brush. Rectifier device according to any one of claims 1 to 5 and (20),
Said rotary shaft, wherein the commutator is provided with (11),
A rotor (13) fixed directly or indirectly to the rotating shaft;
A stator (14) provided via the rotor and a gap (G);
A rotary electric machine (10) characterized by having: The electric rotating machine according to claim 6 , wherein the rotor is provided with the winding (13a).

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