JP2019054698A - Dynamo-electric machine - Google Patents

Abstract

To provide a dynamo-electric machine capable of suppressing generation of arc discharge, while reducing impulsive electromagnetic noise produced by voltage variation.SOLUTION: A dynamo-electric machine 1 is configured so that any one of a pair of auxiliary brushes 61, 62 connected via a diode 66 can slide simultaneously with a first main brush 51 for any of multiple commutator segments 31, the number of commutator segments 31 placed between the pair of auxiliary brushes 61, 62 is less than the number of commutator segments 31 placed between the first and second main brushes 51, 52, any one of a pair of auxiliary brushes 63, 64 connected via a diode 67 can slide simultaneously with the second main brush 52 for any of multiple commutator segments 31, and the number of commutator segments 31 placed between the pair of auxiliary brushes 63, 64 is less than the number of commutator segments 31 placed between the first and second main brushes 51, 52.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a rotating electrical machine.

  Patent Document 1 below discloses a rotating electrical machine with a brush provided with a commutator and a plurality of brushes. This rotating electrical machine has two main brushes that can be slidably contacted with a commutator piece of a commutator, and a pair of auxiliary brushes (“rectifiers” that are connected via a diode and can be slidably contacted with a commutator piece separately from the main brush. Also referred to as a brush.)

JP 2017-34741 A

  According to the rotating electrical machine described above, when the commutator piece is separated from the main brush, a bypass current flows through the energization path including the pair of auxiliary brushes and diodes. The potential difference between them is kept low. Therefore, it is possible to suppress the occurrence of arc discharge between the main brush and the commutator piece, and it is effective to prevent a reduction in the life of the brush due to the influence of arc energy.

  However, in this rotating electrical machine, when the number of commutator pieces arranged between a pair of auxiliary brushes is large, when a bypass current flows through the energizing path composed of the pair of auxiliary brushes and diodes, the rotating brush slides on one auxiliary brush. A sudden voltage fluctuation occurs between the commutator piece that is in contact with the commutator piece that is in sliding contact with the other auxiliary brush, and this voltage fluctuation can cause non-periodic impulsive electromagnetic noise. There's a problem.

  The present invention has been made in view of such a problem, and an object of the present invention is to provide a rotating electrical machine capable of suppressing the occurrence of arc discharge and reducing impulsive electromagnetic noise caused by voltage fluctuation.

One embodiment of the present invention provides:
A shaft (10) which is a rotation axis;
A rotor (20) fixed to the shaft;
An armature coil (22) wound around the iron core (21) of the rotor;
A commutator (30) electrically connected to the armature coil;
A plurality of commutator pieces (31) arranged in the circumferential direction (Z) of the shaft in the commutator;
A magnet (40) for applying a field to the armature coil;
A plurality of main brushes (51, 52) electrically connected to a power source (E) and capable of sliding contact with the plurality of commutator pieces;
A plurality of auxiliary brushes (61, 62, 63, 64, 71, 72, 73, 74) capable of sliding contact with the plurality of commutator pieces;
With
The plurality of main brushes include a first main brush (51) connected to the positive terminal of the power source and a second main brush (52) connected to the negative terminal of the power source and paired with the first main brush. And include
The plurality of auxiliary brushes include a pair of auxiliary brushes (61, 62) provided to the first main brush and electrically connected to each other via a diode (66), and the second main brush. And a pair of auxiliary brushes (63, 64) electrically connected to each other via a diode (67),
The pair of auxiliary brushes provided for the first main brush is such that either one of the auxiliary brushes can be slidably contacted with any of the plurality of commutator pieces simultaneously with the first main brush, And the number of commutator pieces arranged between the pair of auxiliary brushes is less than the number of commutator pieces arranged between the first main brush and the second main brush,
The pair of auxiliary brushes provided for the second main brush is such that any one of the auxiliary brushes can slide in contact with any of the plurality of commutator pieces simultaneously with the second main brush, And the number of commutator pieces arranged between the pair of auxiliary brushes is configured to be less than the number of commutator pieces arranged between the first main brush and the second main brush. Rotating electric machine (1, 101, 201, 301, 401),
It is in.

In the above rotating electric machine, a pair of auxiliary brushes that are electrically connected to each other via a diode are provided for each of the first main brush and the second main brush. As a result, when the commutator piece is separated from each main brush, the bypass current flows through the energization path consisting of a pair of auxiliary brushes and diodes to bypass the arc energy, thereby rectifying the main brush and the main brush away from each main brush. The potential difference between the child pieces can be kept small. Therefore, generation | occurrence | production of arc discharge between each main brush and a commutator piece can be suppressed.
Further, for both the pair of auxiliary brushes provided for the first main brush and the pair of auxiliary brushes provided for the second main brush, the rectification arranged between the pair of auxiliary brushes When the bypass current flows through the energization path composed of a pair of auxiliary brushes and diodes by suppressing the number of child pieces to be smaller than the number of commutator pieces arranged between the first main brush and the second main brush. Thus, a sudden voltage fluctuation can be prevented from occurring between the commutator piece slidably in contact with one auxiliary brush and the commutator piece slidably in contact with the other auxiliary brush. Therefore, generation of non-periodic impulsive electromagnetic noise due to this voltage fluctuation can be prevented.

As described above, according to the above aspect, it is possible to provide a rotating electrical machine capable of suppressing the occurrence of arc discharge and reducing impulsive electromagnetic noise caused by voltage fluctuation.
In addition, the code | symbol in the parenthesis described in the means to solve a claim and a subject shows the correspondence with the specific means as described in embodiment mentioned later, and limits the technical scope of this invention. It is not a thing.

Sectional drawing along the axial direction of the shaft about the rotary electric machine of Embodiment 1. FIG. The figure which shows typically the cross-sectional structure along the radial direction of the shaft about the rotary electric machine of FIG. The figure which shows typically the surrounding structure of the commutator in FIG. FIG. 4 is a planar development view of a plurality of commutator pieces of the commutator of FIG. 3. The elements on larger scale of the 1st brush arrangement structure of FIG. The elements on larger scale of the 2nd brush arrangement structure of FIG. The figure which shows the state from which the commutator piece was separated from the 1st main brush in FIG. The figure which shows the state from which the commutator piece was separated from the 2nd main brush in FIG. FIG. 9 is a planar development view of a plurality of commutator pieces of a commutator of a rotating electrical machine according to a second embodiment. The elements on larger scale of the 1st brush arrangement structure of FIG. The elements on larger scale of the 2nd brush arrangement structure of FIG. The figure which shows the state which the commutator piece left | separated from the 1st main brush in FIG. The figure which shows the state from which the commutator piece was separated from the 2nd main brush in FIG. FIG. 7 is a planar development view of a plurality of commutator pieces of a commutator of a rotating electrical machine according to a third embodiment. FIG. 9 is a planar development view of a plurality of commutator pieces of a commutator of a rotating electrical machine according to a fourth embodiment. FIG. 10 is a planar development view of a plurality of commutator pieces of a commutator of a rotating electrical machine according to a fifth embodiment.

  Hereinafter, an embodiment according to a rotating electrical machine will be described with reference to the drawings.

  In the drawings of this specification, unless otherwise specified, the axial direction of the shaft constituting the rotating electric machine is indicated by an arrow X, the radial direction of the shaft is indicated by an arrow Y, and the circumferential direction of the shaft is indicated by an arrow Z. Shall. In addition, a rotation direction that is one of the circumferential directions Z is indicated by an arrow Za.

(Embodiment 1)
As shown in FIG. 1, the rotating electrical machine 1 according to the first embodiment is configured as an inner rotor type motor. The rotating electrical machine 1 can be used as a drive motor for various devices including a drive motor for in-vehicle devices, a drive motor for household electricity, and a drive motor for general industrial machines. At this time, the rotating electrical machine 1 may be configured as an electric motor, or may be configured as a motor generator having both functions of an electric motor and a generator.

  The rotating electrical machine 1 includes a cylindrical shaft 10 that is a rotating shaft, and is configured such that the shaft 10 is rotationally driven by electric power supplied from a power source E. The rotating electrical machine 1 includes a housing 2 constituted by a case 3 and a cover 4 and a plurality of components for rotationally driving the shaft 10, and the plurality of components are accommodated in the housing 2. Yes.

  The plurality of components include a plurality of support portions 5 that rotatably support the shaft 10, a rotor 20 as a rotor, a commutator 30, a magnet 40 as a stator, and two main brushes 51 and 52. Four auxiliary brushes 61, 62, 63, 64 are included.

  As shown in FIGS. 1 and 2, the rotor 20 is fixed to the shaft 10. The rotor 20 includes an iron core 21 formed by laminating a plurality of electromagnetic steel plates and an armature coil 22, and the armature coil 22 is wound around the iron core 21.

The commutator 30 has a plurality of commutator pieces 31 and is electrically connected to the armature coil 22. In the commutator 30, the plurality of commutator pieces 31 are arranged in the circumferential direction Z of the shaft 10. The two adjacent commutator pieces 31, 31 are separated from each other in the circumferential direction Z and are electrically connected to each other by the armature coil 22.
The number of commutator pieces 31 is not limited and is set to an appropriate value as necessary.

  The magnet 40 is fixed to the inner surface of the case 3 constituting the housing 2 with a gap between the magnet 40 and the rotor 20. The magnet 40 has a function of applying a field to the armature coil 22 and is configured as a field permanent magnet (S pole and N pole) having different polarities.

  As shown in FIGS. 2 and 3, the two main brushes 51 and 52 are both substantially rectangular brushes that can be slidably contacted with the plurality of commutator pieces 31. One first main brush 51 is electrically connected to the positive terminal of the power source E. The other second main brush 52 is configured to be electrically connected to the negative terminal of the power source E and to be paired with the first main brush 51. Therefore, the first main brush 51 can also be referred to as “positive brush” or “one-side main brush”, and the second main brush 52 can also be referred to as “negative brush” or “other-side main brush”.

  All of the four auxiliary brushes 61, 62, 63, 64 are substantially rectangular brushes that can slide in contact with the plurality of commutator pieces 31. These auxiliary brushes include a pair of auxiliary brushes 61 and 62 provided corresponding to the first main brush 51 which is a main brush on one side and electrically connected to each other via a diode 66, and a main brush on the other side. They are classified into a pair of auxiliary brushes 63 and 64 which are provided corresponding to the second main brush 52 which is a brush and are electrically connected to each other via a diode 67. Both of the two diodes 66 and 67 are electronic elements having a rectifying action that allows current to flow only in a certain direction.

  Each of the auxiliary brush 61 and the auxiliary brush 62 is referred to as a “first auxiliary brush”, and the pair of auxiliary brushes 61 and 62 can be referred to as a “pair of first auxiliary brushes”. Each of the auxiliary brush 63 and the auxiliary brush 64 is referred to as a “second auxiliary brush”, and the pair of auxiliary brushes 63 and 64 can be referred to as a “pair of second auxiliary brushes”.

  The energization path including the diode 66 and the pair of auxiliary brushes 61 and 62 is configured as a bypass path for allowing a bypass current to flow when the first main brush 51 is separated from the commutator piece 31. Similarly, the energization path including the diode 67 and the pair of auxiliary brushes 63 and 64 is configured as a bypass path for allowing a bypass current to flow when the first main brush 51 is separated from the commutator piece 31.

  Here, the relative arrangement structure of the main brushes 51 and 52, the pair of auxiliary brushes 61 and 62, and the pair of auxiliary brushes 63 and 64 will be described with reference to FIGS. In these drawings, for convenience of explanation, a plurality of commutator pieces 31 of the commutator 30 are shown in a flat state so that the left-right direction of the drawing is the circumferential direction Z.

  As shown in FIG. 4, in the first brush arrangement structure 1 </ b> A, the pair of auxiliary brushes 61 and 62 are arranged on the front side and the rear side in the rotation direction Za of the plurality of commutator pieces 31 with the first main brush 51 interposed therebetween. Each auxiliary brush is arranged in each of the two. That is, the auxiliary brush 61 is disposed on the front side in the rotational direction Za, and the auxiliary brush 62 is disposed on the rear side in the rotational direction Za.

  Further, among the plurality of commutator pieces 31, the number of commutator pieces 31 disposed between the pair of auxiliary brushes 61 and 62 in the circumferential direction Z is disposed between the first main brush 51 and the second main brush 52. It is comprised so that the number of commutator pieces 31 performed may be less. That is, in FIG. 4, one or two commutator pieces 31 are entirely disposed between both ends 61 a and 62 b of the pair of auxiliary brushes 61 and 62, whereas the first main brush 51 and the second main brush are arranged. The entire three or four commutator pieces 31 are arranged between both ends 51a and 52b of the first 52.

  On the other hand, in the second brush arrangement structure 1B, the pair of auxiliary brushes 63 and 64 are respectively disposed on the front side and the rear side in the rotational direction Za of the plurality of commutator pieces 31 with the second main brush 52 interposed therebetween. Auxiliary brush is arranged. That is, the auxiliary brush 63 is disposed on the front side in the rotational direction Za, and the auxiliary brush 64 is disposed on the rear side in the rotational direction Za.

  Further, among the plurality of commutator pieces 31, the number of commutator pieces 31 arranged between the pair of auxiliary brushes 63 and 64 in the circumferential direction Z is arranged between the first main brush 51 and the second main brush 52. It is comprised so that the number of commutator pieces 31 performed may be less. That is, in FIG. 4, one or two commutator pieces 31 are entirely disposed between both ends 63 a and 42 b of the pair of auxiliary brushes 63 and 64, whereas the first main brush 51 and the second main brush are arranged. The entire three or four commutator pieces 31 are arranged between both ends 51a and 52b of the first 52.

  As shown in FIG. 5, the first brush arrangement structure 1 </ b> A has a front end 51 a on the front side in the rotation direction Za of the first main brush 51 and a front side in the rotation direction Za among the pair of auxiliary brushes 61 and 62. An interval L1 between the auxiliary brush 61 and the rear end 61b on the rear side in the rotation direction Za of the auxiliary brush 61 is configured to be smaller than the minimum value Cmin of the width C in the circumferential direction Z of the commutator piece 31. Accordingly, one auxiliary brush 61 of the pair of auxiliary brushes 61 and 62 can be slidably contacted with the first main brush 51 with respect to any of the plurality of commutator pieces 31. The arrangement condition of the auxiliary brush in this configuration is referred to as “arrangement condition P1”.

  Further, the first brush arrangement structure 1 </ b> A includes the rear end 51 b on the rear side in the rotation direction Za of the first main brush 51 and the auxiliary arranged on the rear side in the rotation direction Za among the pair of auxiliary brushes 61 and 62. The interval L2 between the brush 62 and the front end 62a on the front side in the rotation direction Za is configured to exceed the maximum value Cmax of the width C in the circumferential direction Z of the commutator piece 31. The arrangement condition of the auxiliary brush in this configuration is referred to as “arrangement condition P2”.

  Here, the smallest value among the widths C of all the commutator pieces 31 of the commutator 30 is defined as the “minimum value Cmin”, and the largest value is defined as the “maximum value Cmax”.

  Further, in the pair of auxiliary brushes 61 and 62 of the first brush arrangement structure 1A, the cathode K of the diode 66 is connected to one auxiliary brush 61 arranged on the front side in the rotation direction Za for bypassing arc energy. The anode A of the diode 66 is connected to the other auxiliary brush 62 that is connected and arranged on the rear side in the rotation direction Za.

  As shown in FIG. 6, the second brush arrangement structure 1 </ b> B has a front end 52 a on the front side in the rotation direction Za of the second main brush 52 and a front side in the rotation direction Za among the pair of auxiliary brushes 63 and 64. A distance L1 between the rear end 63b on the rear side in the rotation direction Za of the auxiliary brush 63 arranged is configured to be smaller than the minimum value Cmin of the width C in the circumferential direction Z of the commutator piece 31. Therefore, one auxiliary brush 63 of the pair of auxiliary brushes 63 and 64 can be slidably contacted with any of the plurality of commutator pieces 31 simultaneously with the second main brush 52. The arrangement condition of the auxiliary brush in this configuration is the same as the above arrangement condition P1.

  In addition, the second brush arrangement structure 1B is configured such that the rear end 52b on the rear side in the rotation direction Za of the second main brush 52 and the auxiliary brush arranged on the rear side in the rotation direction Za among the pair of auxiliary brushes 63 and 64. The interval L2 between the brush 64 and the front end 64a on the front side in the rotation direction Za is configured to exceed the maximum value Cmax of the width C in the circumferential direction Z of the commutator piece 31. The arrangement condition of the auxiliary brush in this configuration is the same as the arrangement condition P2 described above.

  Further, in the pair of auxiliary brushes 63 and 64 of the second brush arrangement structure 1B, the anode A of the diode 67 is connected to one auxiliary brush 63 arranged on the front side in the rotation direction Za for bypassing arc energy. The cathode K of the diode 67 is connected to the other auxiliary brush 64 that is connected and arranged on the rear side in the rotation direction Za.

  Further, the brush thickness M in the circumferential direction Z of each of the four auxiliary brushes 61, 62, 63, 64 has a maximum value Dmax of the interval D between two commutator pieces 31, 31 adjacent to each other among the plurality of commutator pieces 31. It is configured to exceed. The configuration condition for specifying this configuration is referred to as “configuration condition Q”.

  Here, the largest value in the interval D for all the commutator pieces 31 of the commutator 30 is defined as the “maximum value Dmax”.

  5 and 6, for convenience, the brush thickness M of each auxiliary brush is adjacent to each other so that the main brush and the auxiliary brush and the plurality of commutator pieces are in sliding contact with each other. It is described so as to be smaller than the distance D between the pieces 31 and 31.

  According to the above configuration condition Q, it is possible to prevent the auxiliary brush from entering the gap between two commutator pieces adjacent to each other. Moreover, since the thickness dimension of the auxiliary brush does not become too small, the auxiliary brush can be easily manufactured.

  Next, the effect of Embodiment 1 is demonstrated, referring FIG.7 and FIG.8 in addition to FIG.5 and FIG.6.

  As shown in FIG. 5, when both the two commutator pieces 31 a and 31 b as the commutator piece 31 are in sliding contact with the first main brush 51, the potential of the commutator piece 31 a is the positive terminal of the power supply E. Is consistent with the potential.

  Thereafter, as shown in FIG. 7, the commutator piece 31 a is separated from the first main brush 51 by the rotation of the commutator 30, and the commutator piece 31 a is in sliding contact with the auxiliary brush 61 and is commutated as the commutator piece 31. The child piece 31 c is in sliding contact with the auxiliary brush 62. At this time, according to the first brush arrangement structure 1 </ b> A, the auxiliary brush 61 is configured to be slidable simultaneously with the first main brush 51 with respect to any of the plurality of commutator pieces 31. 31 a comes into sliding contact with the auxiliary brush 61 before leaving the first main brush 51. For this reason, a bypass current flows from the auxiliary brush 62 toward the auxiliary brush 61 through the energizing path including the pair of auxiliary brushes 61 and 62 and the diode 66 (see the arrow in FIG. 7), and the arc energy is bypassed.

  Thereby, the electric potential difference between the 1st main brush 51 and the commutator piece 31a can be suppressed small, and it can suppress that arc discharge generate | occur | produces between the 1st main brush 51 and the commutator piece 31a. . Therefore, the life of the first main brush 51 can be improved.

  Further, by suppressing the number of commutator pieces 31 arranged between the pair of auxiliary brushes 61 and 62, the potential difference when the bypass current flows through the energization path including the pair of auxiliary brushes 61 and 62 and the diode 66 is reduced. By reducing the size, it is possible to prevent sudden voltage fluctuations between the commutator piece 31 a in sliding contact with one auxiliary brush 61 and the commutator piece 31 c in sliding contact with the other auxiliary brush 62. For this reason, impulsive electromagnetic noise caused by voltage fluctuation can be reduced.

  In particular, since the first brush arrangement structure 1A satisfies the arrangement conditions P1 and P2, the auxiliary brush 61 is arranged at a position close to the first main brush 51, so that the effect of suppressing arc discharge is enhanced and a pair of auxiliary brushes are provided. By arranging both the brushes 61 and 62 at a position close to the same level as the first main brush 51, it is possible to suppress the voltage fluctuation when the bypass current flows through the energization path and to increase the electromagnetic noise reduction effect.

  Similarly, as shown in FIG. 6, in the state where the two commutator pieces 31d and 31e as the commutator piece 31 are both in sliding contact with the second main brush 52, the potential of the commutator piece 31d is the power supply E. This corresponds to the potential of the negative electrode terminal.

  Thereafter, as shown in FIG. 8, the commutator piece 31 d is separated from the second main brush 52 by the rotation of the commutator 30, and the commutator piece 31 d is in sliding contact with the auxiliary brush 63 and is commutated as the commutator piece 31. The child piece 31f is in sliding contact with the auxiliary brush 64. At this time, according to the second brush arrangement structure 1B, the auxiliary brush 63 is configured to be slidable simultaneously with the second main brush 52 with respect to any of the plurality of commutator pieces 31. 31 d comes into sliding contact with the auxiliary brush 63 before leaving the second main brush 52. For this reason, a bypass current flows from the auxiliary brush 63 toward the auxiliary brush 64 through the energizing path including the pair of auxiliary brushes 63 and 64 and the diode 67 (see the arrow in FIG. 8), and the arc energy is bypassed.

  Thereby, the potential difference between the second main brush 52 and the commutator piece 31d can be suppressed to be small, and the occurrence of arc discharge between the second main brush 52 and the commutator piece 31d can be suppressed. . Therefore, the life of the second main brush 52 can be improved.

  In addition, by reducing the number of commutator pieces 31 disposed between the pair of auxiliary brushes 63 and 64, the potential difference when the bypass current flows through the energization path including the pair of auxiliary brushes 63 and 64 and the diode 67 is reduced. By reducing the size, it is possible to prevent sudden voltage fluctuation between the commutator piece 31d slidably in contact with one auxiliary brush 63 and the commutator piece 31f slidably in contact with the other auxiliary brush 64. For this reason, impulsive electromagnetic noise caused by voltage fluctuation can be reduced.

  In particular, since the second brush arrangement structure 1B satisfies the arrangement conditions P1 and P2, the auxiliary brush 63 is arranged at a position close to the second main brush 52, thereby improving the effect of suppressing arc discharge and a pair of auxiliary By arranging the brushes 63 and 64 at a position close to the second main brush 52 at the same level, it is possible to suppress the voltage fluctuation when the bypass current flows through the energization path, and to increase the electromagnetic noise reduction effect.

(Embodiment 2)
In the rotating electrical machine 101 of the second embodiment, the relative arrangement structure of the two main brushes 51 and 52 and the pair of auxiliary brushes 61 and 62 and the pair of auxiliary brushes 63 and 64 is the same as that of the rotating electrical machine 1 of the first embodiment. It is different from the one. Only this difference will be described below.
Other configurations are the same as those of the first embodiment.

  As shown in FIG. 9, in the first brush arrangement structure 101 </ b> A of the rotating electrical machine 101, the pair of auxiliary brushes 61 and 62 are ahead of the first main brush 51 in the rotational direction Za of the plurality of commutator pieces 31. Both auxiliary brushes are arranged on the side.

  In the first brush arrangement structure 101A, the number of commutator pieces 31 arranged between the pair of auxiliary brushes 61 and 62 in the circumferential direction Z among the plurality of commutator pieces 31 is the same as that of the first main brush 51 and the second brush arrangement structure 101A. It is comprised so that the number of commutator pieces 31 arrange | positioned between the main brushes 52 may be less.

  On the other hand, in the second brush arrangement structure 101 </ b> B of the rotating electrical machine 101, the pair of auxiliary brushes 63, 64 are located on the front side in the rotational direction Za of the plurality of commutator pieces 31 with respect to the second main brush 52. A brush is also arranged.

  In the second brush arrangement structure 101B, the number of commutator pieces 31 arranged between the pair of auxiliary brushes 63 and 64 in the circumferential direction Z among the plurality of commutator pieces 31 is the same as that of the first main brush 51 and the second brush arrangement structure 101B. It is comprised so that the number of commutator pieces 31 arrange | positioned between the main brushes 52 may be less.

  As shown in FIG. 10, the first brush arrangement structure 101 </ b> A has a front end 51 a on the front side in the rotation direction Za of the first main brush 51 and a rear side in the rotation direction Za among the pair of auxiliary brushes 61 and 62. A distance L3 between the auxiliary brush 62 and the rear end 62b on the rear side in the rotation direction Za of the auxiliary brush 62 is configured to be smaller than the minimum value Cmin of the width C in the circumferential direction Z of the commutator piece 31. Accordingly, one auxiliary brush 62 of the pair of auxiliary brushes 61 and 62 can be slidably contacted with the first main brush 51 simultaneously with any of the plurality of commutator pieces 31. The arrangement condition of the auxiliary brush in this configuration is referred to as “arrangement condition P3”.

  Further, the first brush arrangement structure 101A includes a front end 62a on the front side in the rotation direction Za of the auxiliary brush 62 arranged on the rear side in the rotation direction Za of the pair of auxiliary brushes 61 and 62, and a rotation direction Za. An interval L4 between the auxiliary brush 61 disposed on the front side and the rear end 61b on the rear side in the rotation direction Za is configured to exceed the maximum value Cmax of the width C in the circumferential direction Z of the commutator piece 31. . The arrangement condition of the auxiliary brush in this configuration is referred to as “arrangement condition P4”.

  Further, in the pair of auxiliary brushes 61 and 62 of the first brush arrangement structure 101A, the anode A of the diode 66 is connected to one auxiliary brush 61 arranged on the front side in the rotation direction Za for bypassing arc energy. The cathode K of the diode 66 is connected to the other auxiliary brush 62 that is connected and arranged on the rear side in the rotation direction Za.

  As shown in FIG. 11, the second brush arrangement structure 101 </ b> B is arranged on the front end 52 a on the front side in the rotation direction Za of the second main brush 52 and on the rear side in the rotation direction Za among the pair of auxiliary brushes 63 and 64. A distance L3 between the auxiliary brush 64 and the rear end 64b on the rear side in the rotation direction Za of the auxiliary brush 64 is configured to be smaller than the minimum value Cmin of the width C in the circumferential direction Z of the commutator piece 31. Therefore, one auxiliary brush 64 of the pair of auxiliary brushes 63 and 64 can be slidably contacted with any of the plurality of commutator pieces 31 simultaneously with the second main brush 52. The arrangement condition of the auxiliary brush in this configuration is the same as the arrangement condition P3.

  Further, the second brush arrangement structure 101B includes a front end 64a on the front side of the rotation direction Za of the auxiliary brush 64 arranged on the rear side in the rotation direction Za of the pair of auxiliary brushes 63 and 64, and a rotation direction Za. The distance L4 between the auxiliary brush 63 disposed on the front side and the rear end 63b on the rear side in the rotation direction Za is configured to exceed the maximum value Cmax of the width C in the circumferential direction Z of the commutator piece 31. . The arrangement condition of the auxiliary brush in this configuration is the same as the arrangement condition P4 described above.

  In addition, in the pair of auxiliary brushes 63 and 64 of the second brush arrangement structure 101B, the cathode K of the diode 67 is connected to one auxiliary brush 63 arranged on the front side in the rotation direction Za for bypassing arc energy. The anode A of the diode 67 is connected to the other auxiliary brush 64 which is connected and arranged on the rear side in the rotation direction Za.

  Similarly to the case of the first embodiment, in the second embodiment, the above-described configuration condition Q can be applied to at least one of the four auxiliary brushes 61, 62, 63, 64.

  Next, the effect of Embodiment 2 is demonstrated, referring FIG.12 and FIG.13 in addition to FIG.10 and FIG.11.

  As shown in FIG. 10, when the commutator piece 31 c is in sliding contact with the first main brush 51, the potential of the commutator piece 31 c matches the potential of the positive terminal of the power source E.

  Then, as shown in FIG. 12, the commutator piece 31c is separated from the first main brush 51 by the rotation of the commutator 30, the commutator piece 31a is in sliding contact with the auxiliary brush 61, and the commutator piece 31c is the auxiliary brush. 62 slidably contacts. At this time, according to the first brush arrangement structure 101 </ b> A, the auxiliary brush 62 is configured to be slidable simultaneously with the first main brush 51 with respect to any of the plurality of commutator pieces 31. 31 c comes into sliding contact with the auxiliary brush 62 before leaving the first main brush 51. For this reason, a bypass current flows from the auxiliary brush 61 toward the auxiliary brush 62 through the energizing path including the pair of auxiliary brushes 61 and 62 and the diode 66 (see the arrow in FIG. 12), and the arc energy is bypassed.

  Thereby, the electric potential difference between the 1st main brush 51 and the commutator piece 31c can be suppressed small, and it can suppress that arc discharge generate | occur | produces between the 1st main brush 51 and the commutator piece 31c. . Therefore, the life of the first main brush 51 can be improved.

  Further, by suppressing the number of commutator pieces 31 arranged between the pair of auxiliary brushes 61 and 62, the potential difference when the bypass current flows through the energization path including the pair of auxiliary brushes 61 and 62 and the diode 66 is reduced. By reducing the size, it is possible to prevent sudden voltage fluctuations between the commutator piece 31 a in sliding contact with one auxiliary brush 61 and the commutator piece 31 c in sliding contact with the other auxiliary brush 62. For this reason, impulsive electromagnetic noise caused by voltage fluctuation can be reduced.

  Similarly, as shown in FIG. 11, when the commutator piece 31 f is in sliding contact with the second main brush 52, the potential of the commutator piece 31 f matches the potential of the negative terminal of the power source E.

  Thereafter, as shown in FIG. 13, by the rotation of the commutator 30, the commutator piece 31f is separated from the second main brush 52, the commutator piece 31d is in sliding contact with the auxiliary brush 63, and the commutator piece 31f is the auxiliary brush. 64 is in sliding contact. At this time, according to the second brush arrangement structure 101 </ b> B, the auxiliary brush 64 is configured to be slidable simultaneously with the second main brush 52 with respect to any of the plurality of commutator pieces 31. 31 f slidably contacts the auxiliary brush 64 before leaving the second main brush 52. For this reason, a bypass current flows from the auxiliary brush 64 toward the auxiliary brush 63 through the energizing path including the pair of auxiliary brushes 63 and 64 and the diode 67 (see the arrow in FIG. 13), and the arc energy is bypassed.

  Thereby, the electric potential difference between the 2nd main brush 52 and the commutator piece 31f can be suppressed small, and it can suppress that arc discharge generate | occur | produces between the 2nd main brush 52 and the commutator piece 31f. . Therefore, the life of the second main brush 52 can be improved.

  In addition, by reducing the number of commutator pieces 31 disposed between the pair of auxiliary brushes 63 and 64, the potential difference when the bypass current flows through the energization path including the pair of auxiliary brushes 63 and 64 and the diode 67 is reduced. By reducing the size, it is possible to prevent sudden voltage fluctuation between the commutator piece 31d slidably in contact with one auxiliary brush 63 and the commutator piece 31f slidably in contact with the other auxiliary brush 64. For this reason, impulsive electromagnetic noise caused by voltage fluctuation can be reduced.

  In addition, the same effects as those of the first embodiment are obtained.

(Embodiment 3)
The rotating electrical machine 201 of the third embodiment has a relative arrangement structure of the two main brushes 51 and 52, the pair of auxiliary brushes 61 and 62, and the pair of auxiliary brushes 63 and 64, respectively. It is different from the one. Only this difference will be described below.
Other configurations are the same as those of the first embodiment.

  As shown in FIG. 14, in the rotating electric machine 201, the first brush arrangement structure 201 </ b> A is the same as the first brush arrangement structure 1 </ b> A (see FIG. 5) of the first embodiment, while the second brush arrangement structure The structure 201B is the same as the second brush arrangement structure 101B (see FIG. 11) of the second embodiment.

  In other words, in the first brush arrangement structure 201A, the pair of auxiliary brushes 61 and 62 are arranged on the front side and the rear side in the rotation direction Za of the plurality of commutator pieces 31 with the first main brush 51 as one side main brush interposed therebetween. Each auxiliary brush is arranged in each of the two.

  Referring to FIG. 5, the first brush arrangement structure 201 </ b> A rotates between the front end 51 a on the front side in the rotation direction Za of the first main brush 51 that is one side main brush and the pair of auxiliary brushes 61 and 62. The distance L1 between the auxiliary brush 61 disposed on the front side in the direction Za and the rear end 61b on the rear side in the rotation direction Za is configured to be smaller than the minimum value Cmin of the width C in the circumferential direction Z of the commutator piece 31. Has been.

  In addition, the first brush arrangement structure 201A includes a rear end 51b on the rear side in the rotation direction Za of the first main brush 51 that is the one-side main brush, and a rear side in the rotation direction Za of the pair of auxiliary brushes 61 and 62. The distance L2 between the auxiliary brush 62 arranged on the side and the front end 62a on the front side in the rotation direction Za is configured to exceed the maximum value Cmax of the width C in the circumferential direction Z of the commutator piece 31.

  Further, in the first brush arrangement structure 201A, the cathode K of the diode 66 is connected to one auxiliary brush 61 arranged on the front side in the rotation direction Za, and the other brush arranged on the rear side in the rotation direction Za. An anode A of a diode 66 is connected to the auxiliary brush 62.

  On the other hand, in the second brush arrangement structure 201 </ b> B, the pair of auxiliary brushes 63, 64 are either on the front side in the rotational direction Za of the plurality of commutator pieces 31 than the second main brush 52 that is the other side main brush. An auxiliary brush is also arranged.

  Referring to FIG. 11, the second brush arrangement structure 201 </ b> B includes a front end 52 a on the front side in the rotation direction Za of the second main brush 52 that is the other main brush, and the rotation direction of the pair of auxiliary brushes 63 and 64. The distance L3 between the auxiliary brush 64 disposed on the rear side of Za and the rear end 64b on the rear side in the rotation direction Za is configured to be smaller than the minimum value Cmin of the width C in the circumferential direction Z of the commutator piece 31. ing.

  Further, the second brush arrangement structure 201B includes a front end 64a on the front side in the rotation direction Za of the auxiliary brush 64 arranged on the rear side in the rotation direction Za of the pair of auxiliary brushes 63 and 64, and a rotation direction Za. The distance L4 between the auxiliary brush 63 disposed on the front side and the rear end 63b on the rear side in the rotation direction Za is configured to exceed the maximum value Cmax of the width C in the circumferential direction Z of the commutator piece 31. .

  Further, in the second brush arrangement structure 201B, the cathode K of the diode 67 is connected to one auxiliary brush 63 arranged on the front side in the rotation direction Za and the other brush arranged on the rear side in the rotation direction Za. The anode A of the diode 67 is connected to the auxiliary brush 64.

  As in the case of the first embodiment, in the third embodiment, the above-described configuration condition Q can be applied to at least one of the four auxiliary brushes 61, 62, 63, 64.

  According to the above-described third embodiment, it is possible to obtain an operation effect that combines the above-described operation effect obtained by the first brush arrangement structure 1A and the above-described operation effect obtained by the second brush arrangement structure 101B.

  In addition, the same effects as those of the first embodiment are obtained.

As a modification of the arrangement structure of the third embodiment, the first brush arrangement structure 201A is the same as the first brush arrangement structure 101A (see FIG. 10) of the second embodiment, and the second brush arrangement structure 201B. Can be the same as the second brush arrangement structure 1B (see FIG. 6) of the first embodiment.
Thereby, the operation effect which has the above-mentioned operation effect obtained by the 1st brush arrangement structure 101A and the above-mentioned operation effect obtained by the 2nd brush arrangement structure 1B is obtained.
In addition, the same effects as those of the first embodiment are obtained.

(Embodiment 4)
In the rotating electrical machine 301 of the fourth embodiment, the relative arrangement structure of the two main brushes 51 and 52 and the pair of auxiliary brushes 61 and 62 and the pair of auxiliary brushes 63 and 64 is the same as that of the rotating electrical machine 201 of the third embodiment. It is different from the one. Only this difference will be described below.
Other configurations are the same as those of the third embodiment.

  As shown in FIG. 15, in this rotating electrical machine 301, the auxiliary brush 62 of the pair of auxiliary brushes 61 and 62 and the auxiliary brush 63 of the pair of auxiliary brushes 63 and 64 are integrated with each other. Two common auxiliary brushes 65 are configured. In this case, the number of auxiliary brushes is three.

  In the case of this configuration, the number of commutator pieces 31 arranged between the pair of auxiliary brushes 61 and 65 and the number of commutator pieces 31 arranged between the pair of auxiliary brushes 65 and 64 are both the first. It is comprised so that the number of commutator pieces 31 arrange | positioned between the main brush 51 and the 2nd main brush 52 may be less. That is, in FIG. 15, the entire three commutator pieces 31 are disposed between both ends of the pair of auxiliary brushes 61 and 65, and the entire three commutator pieces 31 are disposed between both ends of the pair of auxiliary brushes 65 and 64. In contrast, the entire five or six commutator pieces 31 are arranged between both ends of the first main brush 51 and the second main brush 52.

  The arrangement conditions corresponding to the arrangement conditions P1 and P2 are applied to the arrangement of the pair of auxiliary brushes 61 and 65, and the arrangement corresponding to the arrangement conditions P3 and P4 is applied to the arrangement of the pair of auxiliary brushes 65 and 64. Conditions are applied.

  As in the case of the first embodiment, in the fourth embodiment, the above-described configuration condition Q can be applied to at least one of the two auxiliary brushes 61 and 62 and the one common auxiliary brush 65.

According to the above-described fourth embodiment, a cost reduction effect can be obtained by reducing the number of auxiliary brushes as compared with the third embodiment.
In addition, the same operational effects as those of the third embodiment are obtained.

(Embodiment 5)
The rotating electrical machine 401 according to the fifth embodiment uses four auxiliary brushes 71, 72, 73, 74 and two diodes 76, 77 in order to reverse the polarity of the first main brush 51 and the second main brush 52. Is different from that of the rotating electrical machine 1 of the first embodiment. Only this difference will be described below.
Other configurations are the same as those of the first embodiment.

  As shown in FIG. 16, the rotating electrical machine 401 includes a pair of auxiliary brushes 71 and 72 for polarity reversal provided separately from the pair of auxiliary brushes 61 and 62 corresponding to the first main brush 51, and the second A pair of auxiliary brushes 73 and 74 for polarity reversal provided separately from the pair of auxiliary brushes 63 and 64 corresponding to the main brush 52 are provided.

  Like the pair of auxiliary brushes 61 and 62, the pair of auxiliary brushes 71 and 72 are electrically connected to each other via a diode 76, and are disposed so as to sandwich the first main brush 51 from both sides in the rotation direction Za. ing. Specifically, the auxiliary brush 71 is disposed in front of the auxiliary brush 61 in the rotation direction Za. The auxiliary brush 72 is disposed between the first main brush 51 and the auxiliary brush 62. The pair of auxiliary brushes 71 and 72 are configured such that the interval in the circumferential direction Z coincides with the interval in the circumferential direction Z of the pair of auxiliary brushes 61 and 62.

  In the pair of auxiliary brushes 71 and 72, the cathode K of the diode 76 is connected to one auxiliary brush 71 arranged on the front side in the rotation direction Za, and the other auxiliary brush 72 arranged on the rear side in the rotation direction Za. Is connected to the anode A of the diode 76.

  On the other hand, the pair of auxiliary brushes 73 and 74 are electrically connected to each other via the diode 77 and the second main brush 52 is moved from both sides in the rotational direction Za, like the pair of auxiliary brushes 63 and 64. It is arranged so as to be sandwiched. Specifically, the auxiliary brush 73 is disposed in front of the auxiliary brush 63 in the rotation direction Za. The auxiliary brush 74 is disposed between the second main brush 52 and the auxiliary brush 64. Further, the pair of auxiliary brushes 73 and 74 are configured such that the interval in the circumferential direction Z coincides with the interval in the circumferential direction Z of the pair of auxiliary brushes 63 and 64.

  In the pair of auxiliary brushes 73 and 74, the anode A of the diode 77 is connected to one auxiliary brush 73 disposed on the front side in the rotational direction Za, and the other auxiliary brush 74 disposed on the rear side in the rotational direction Za. To the cathode K of the diode 77.

  As in the case of the first embodiment, in the fifth embodiment, the above-described configuration condition Q is applied to at least one of the eight auxiliary brushes 61, 62, 63, 64, 71, 72, 73, 74. You can also

  In the rotating electrical machine 401, in order to bypass the arc energy in normal times, the energization path including the diode 66 and the pair of auxiliary brushes 61 and 62 is effective for the first main brush 51, and the first For the two main brushes 52, an energization path composed of a diode 67 and a pair of auxiliary brushes 63 and 64 is effective.

  On the other hand, when the polarities of the first main brush 51 and the second main brush 52 are reversed from the normal time, the diode 76 and a pair of diodes are paired with respect to the first main brush 51 in order to bypass the arc energy. The energization path including the auxiliary brushes 71 and 72 is effective, and the energization path including the diode 77 and the pair of auxiliary brushes 73 and 74 is effective for the second main brush 52.

According to the fifth embodiment described above, it is possible to use the first main brush 51 and the second main brush 52 with the polarities reversed.
In addition, the same effects as those of the first embodiment are obtained.

  The present invention is not limited to the above-described exemplary embodiments, and various applications and modifications can be considered without departing from the object of the present invention. For example, the following embodiments applying the above-described embodiment can be implemented.

  In the above embodiment, the number of commutator pieces arranged between the pair of auxiliary brushes is not limited, and this number represents the number of commutator pieces arranged between the two main brushes. It can be set as appropriate on the condition that it falls below.

  In the above embodiment, the case where the thickness of at least one of the plurality of auxiliary brushes exceeds the maximum value of the distance between the two commutator pieces adjacent to each other is exemplified. It is also possible to employ a structure in which the thickness is equal to or less than the maximum value of the distance between two adjacent commutator pieces.

  In the above embodiment, the case where the number of main brushes is two has been illustrated, but the number of main brushes is not limited to two and can be increased beyond this.

  In the above embodiment, the case where the number of auxiliary brushes is three, four, or eight is illustrated, but the number of auxiliary brushes is not limited to these, and may be appropriately determined as necessary. Can be set to

  In the above embodiment, the rotary electric machines 1, 101, 201, 301, and 401 which are inner rotor type motors are illustrated, but the brush arrangement structure in the rotary electric machine can also be applied to an outer rotor type motor.

1, 101, 201, 301, 401 Rotating electrical machine 10 Shaft 20 Rotor 21 Iron core 22 Armature coil 30 Commutator 31 Commutator piece 40 Magnet 51 First main brush (main brush, one side main brush)
51a, 52a Front end 52 Second main brush (main brush, other side main brush)
61, 62, 63, 64, 71, 72, 73, 74 Auxiliary brush 61b, 63b Rear end 62a, 64a Front end 65 Shared auxiliary brush 66, 67, 76, 77 Diode A Anode C Width Cmin Minimum value Cmax Maximum value D Interval Dmax Maximum value E Power supply K Cathode L1, L2, L3, L4 Spacing M Brush thickness Z Circumferential direction Za Rotating direction

Claims (7)

A shaft (10) which is a rotation axis;
A rotor (20) fixed to the shaft;
An armature coil (22) wound around the iron core (21) of the rotor;
A commutator (30) electrically connected to the armature coil;
A plurality of commutator pieces (31) arranged in the circumferential direction (Z) of the shaft in the commutator;
A magnet (40) for applying a field to the armature coil;
A plurality of main brushes (51, 52) electrically connected to a power source (E) and capable of sliding contact with the plurality of commutator pieces;
A plurality of auxiliary brushes (61, 62, 63, 64, 71, 72, 73, 74) capable of sliding contact with the plurality of commutator pieces;
With
The plurality of main brushes include a first main brush (51) connected to the positive terminal of the power source and a second main brush (52) connected to the negative terminal of the power source and paired with the first main brush. And include
The plurality of auxiliary brushes include a pair of auxiliary brushes (61, 62) provided to the first main brush and electrically connected to each other via a diode (66), and the second main brush. And a pair of auxiliary brushes (63, 64) electrically connected to each other via a diode (67),
The pair of auxiliary brushes provided for the first main brush is such that either one of the auxiliary brushes can be slidably contacted with any of the plurality of commutator pieces simultaneously with the first main brush, And the number of commutator pieces arranged between the pair of auxiliary brushes is less than the number of commutator pieces arranged between the first main brush and the second main brush,
The pair of auxiliary brushes provided for the second main brush is such that any one of the auxiliary brushes can slide in contact with any of the plurality of commutator pieces simultaneously with the second main brush, And the number of commutator pieces arranged between the pair of auxiliary brushes is configured to be less than the number of commutator pieces arranged between the first main brush and the second main brush. Rotating electric machine (1, 101, 201, 301, 401). The pair of auxiliary brushes are respectively disposed on the front side and the rear side in the rotation direction (Za) of the plurality of commutator pieces with the main brush interposed between the first main brush and the second main brush. Auxiliary brush is arranged,
Each of the first main brush and the second main brush has a front end (51a, 52a) on the front side in the rotational direction and a pair of auxiliary brushes corresponding to the main brush on the front side in the rotational direction. The distance (L1) between the rear end (61b, 63b) on the rear side in the rotational direction of the auxiliary brush (61, 63) is the minimum value (Cmin of the circumferential width (C) of the commutator piece. ) And the rear end (51b, 52b) on the rear side of each of the first main brush and the second main brush in the rotation direction, and the rotation of the pair of auxiliary brushes corresponding to the main brush. The distance (L2) between the auxiliary brushes (62, 64) arranged on the rear side in the direction and the front ends (62a, 64a) on the front side in the rotational direction is the width (C) in the circumferential direction of the commutator piece. Exceeding the maximum value (Cmax) of
In the pair of auxiliary brushes corresponding to the first main brush, the cathode (K) of the diode is connected to one auxiliary brush (61) arranged on the front side in the rotation direction, and the rear in the rotation direction. The anode (A) of the diode is connected to the other auxiliary brush (62) arranged on the side,
In the pair of auxiliary brushes corresponding to the second main brush, an anode (A) of the diode is connected to one auxiliary brush (63) disposed on the front side in the rotation direction, and the rear in the rotation direction. The rotating electrical machine according to claim 1, wherein the cathode (K) of the diode is connected to the other auxiliary brush (64) arranged on the side. The pair of auxiliary brushes are arranged such that each auxiliary brush is arranged on the front side in the rotational direction of the plurality of commutator pieces from the main brush for each of the first main brush and the second main brush.
Each of the first main brush and the second main brush has a front end (51a, 52a) on the front side in the rotational direction and a rear side in the rotational direction of the pair of auxiliary brushes corresponding to the main brush. The distance (L3) between the rear end (62b, 64b) on the rear side in the rotational direction of the auxiliary brush (62, 64) is the minimum value (Cmin of the circumferential width (C) of the commutator piece. ) And the auxiliary brushes (62, 64) arranged on the rear side in the rotational direction of the pair of auxiliary brushes corresponding to the first main brush and the second main brush in the rotational direction. A distance (L4) between the front end (62a, 64a) on the front side and the rear end (61b, 63b) on the rear side in the rotational direction of the auxiliary brush (61, 63) disposed on the front side in the rotational direction. Is the circumference of the commutator piece Exceeds the maximum value of the width (C) (Cmax),
In the pair of auxiliary brushes corresponding to the first main brush, the anode (A) of the diode is connected to one auxiliary brush (61) disposed on the front side in the rotation direction, and the rear in the rotation direction. The cathode (K) of the diode is connected to the other auxiliary brush (62) arranged on the side,
In the pair of auxiliary brushes corresponding to the second main brush, the cathode (K) of the diode is connected to one auxiliary brush (63) disposed on the front side in the rotation direction, and the rear in the rotation direction. The rotating electrical machine according to claim 1, wherein the anode (A) of the diode is connected to the other auxiliary brush (64) arranged on the side. The pair of auxiliary brushes provided corresponding to the one side main brush (51) which is one side of the first main brush and the second main brush is defined as a pair of first auxiliary brushes (61, 62). The pair of auxiliary brushes provided corresponding to the other side main brush (52), which is the other side of the first main brush and the second main brush, are paired with a pair of second auxiliary brushes (63, 64). When
Each of the pair of first auxiliary brushes is disposed on each of the front side and the rear side in the rotation direction (Za) of the plurality of commutator pieces with the one side main brush interposed therebetween,
The pair of second auxiliary brushes are arranged such that any second auxiliary brush is arranged on the front side in the rotational direction with respect to the other side main brush,
The front end (51a) on the front side in the rotation direction of the one-side main brush and the rotation direction of the first auxiliary brush (61) disposed on the front side in the rotation direction among the pair of first auxiliary brushes. The distance (L1) between the rear end (61b) on the rear side is less than the minimum value (Cmin) of the circumferential width (C) of the commutator piece, and the rear of the one-side main brush in the rotational direction. A rear end (51b) on the side and a front end (62a) on the front side in the rotational direction of the first auxiliary brush (62) disposed on the rear side in the rotational direction among the pair of first auxiliary brushes. The interval (L2) exceeds the maximum value (Cmax) of the circumferential width (C) of the commutator piece,
The front end (52a) on the front side in the rotational direction of the other main brush and the second auxiliary brush (64) disposed on the rear side in the rotational direction of the pair of second auxiliary brushes in the rotational direction. The distance (L3) between the rear end (64b) on the rear side is less than the minimum value (Cmin) of the circumferential width (C) of the commutator piece, and the pair of pairs corresponding to the other main brush. Among the second auxiliary brushes, the second auxiliary brush (64) disposed on the rear side in the rotational direction and the front end (64a) on the front side in the rotational direction and the second auxiliary brush disposed on the front side in the rotational direction. The distance (L4) between the brush (63) and the rear end (63b) on the rear side in the rotational direction exceeds the maximum value (Cmax) of the circumferential width (C) of the commutator piece,
In the pair of first auxiliary brushes, the cathode (K) of the diode is connected to one first auxiliary brush (61) arranged on the front side in the rotation direction, and arranged on the rear side in the rotation direction. The anode (A) of the diode is connected to the other first auxiliary brush (62),
In the pair of second auxiliary brushes, the cathode (K) of the diode is connected to one second auxiliary brush (63) arranged on the front side in the rotation direction, and arranged on the rear side in the rotation direction. The rotating electrical machine according to claim 1, wherein the anode (A) of the diode is connected to the other second auxiliary brush (64).   The other first auxiliary brush of the pair of first auxiliary brushes and the one second auxiliary brush of the pair of second auxiliary brushes are integrated into one common auxiliary brush (65 The rotating electrical machine according to claim 4, which is configured as:   In order to use the first main brush and the second main brush with the polarity reversed, the plurality of auxiliary brushes are provided separately from the pair of auxiliary brushes corresponding to the first main brush, A pair of auxiliary brushes (71, 72) for polarity reversal electrically connected to each other via a diode (76) and the pair of auxiliary brushes corresponding to the second main brush are provided separately from the diode. A rotating electrical machine according to any one of claims 1 to 5, comprising a pair of auxiliary brushes (73, 74) for polarity reversal that are electrically connected to each other via (77).   The maximum value of the distance (D) between two commutator pieces (31, 31) adjacent to each other in the circumferential brush thickness (M) of at least one of the plurality of auxiliary brushes. The rotating electrical machine according to claim 1, wherein the rotating electrical machine is configured to exceed (Dmax).

Images