JP2007124871A - Commutator, short-circuiting member, and method for manufacturing commutator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a commutator to which a surge-absorbing element can be fitted easily. <P>SOLUTION: The commutator C1 includes a commutator main body 41 having a plurality of segments 1 to 24 provided in the circumferential direction and a short-circuiting member 42 fixed to the commutator main body 41 and having two short-circuit constituting member groups 51, 52. Each short-circuit constituting member groups 51, 52 has a plurality of outer circumferential side terminals 51a, 52a arranged in the circumferential direction and connected to the corresponding segments 1 to 24, a plurality of inner circumferential side terminals 51b, 52b arranged in the circumferential direction inside the outer circumferential side terminals 51a, 52a, and connection parts 51c, 52c connecting the corresponding outer circumferential side terminals 51a, 52a and the inner circumferential side terminals 51b, 52b respectively. Furthermore, a varistor 71 is interposed between the circumferentially adjoining inner circumferential side terminals 51b, 52b and is integrally formed with the inner circumferential side terminals 51b, 52b so as to electrically connect the mutual inner circumferential side terminals 51b, 52b. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a commutator provided in a motor, a short-circuit member provided in the commutator, and a method of manufacturing the commutator.

  In a motor in which power is supplied from a brush that is in sliding contact with a commutator segment, spark discharge may occur between the commutator and the brush during driving. This spark discharge is one cause of a reduction in the life of the brush. Therefore, some conventional motors include a varistor, which is one of the surge absorbing elements, in order to prevent spark discharge.

  For example, in the motor described in Patent Document 1, the varistor is fixed to the commutator. This commutator includes a cylindrical insulator press-fitted and fixed to the rotating shaft of the motor, and three segments fixed to the outer peripheral surface of the insulator. The three segments are respectively connected to end portions of armature coils provided in the motor, and are in sliding contact with power supply brushes for supplying current to the armature coils. In addition, a riser extends radially outward from one end of the three segments in the longitudinal direction, and an annular varistor is disposed on the riser. The varistor is sandwiched between the riser and the contact piece by bending the contact piece formed at the tip of the riser. With this configuration, the varistor and each segment are electrically connected, and the varistor is electrically interposed between both end portions of the armature coil.

The configuration in which a varistor is electrically interposed between both end portions of the armature coil as in the motor described in Patent Document 1 can also be applied to a multipolar motor such as the motor described in Patent Document 2. Patent Document 2 describes, as an example, a motor that includes six permanent magnets and eight armature coils. In this motor, the number of power supply brushes is set to two by short-circuiting the segments having the same potential among the 24 segments with a short-circuit member.
JP 2005-5293 A JP 2005-137193 A

  By the way, when providing the varistor like the motor described in Patent Document 1 in the motor described in Patent Document 2, the motor described in Patent Document 2 is more multipolar than the motor described in Patent Document 1. Accordingly, the number of clamping pieces that clamp the varistor together with the riser is increased as compared with the motor described in Patent Document 1. When the number of the sandwiching pieces is increased in this way, the process of bending the sandwiching pieces and providing the varistor on the commutator becomes complicated. And if the process of providing the varistor on the commutator becomes complicated, the productivity of the commutator may be reduced.

  The present invention has been made in view of such circumstances, and its purpose is to provide a commutator in which a surge absorbing element can be easily provided, a short-circuit member provided in the commutator, and a method of manufacturing the commutator. It is to provide.

  In order to solve the above-mentioned problem, the invention according to claim 1 includes a commutator body having a plurality of segments provided in the circumferential direction, a plurality of peripheral terminals arranged in the circumferential direction and respectively connected to the segments, and the outer periphery. A plurality of inner peripheral terminals arranged in the circumferential direction inside the side terminal, and a plurality of connecting portions that respectively connect the outer peripheral terminal and the inner peripheral terminal with a predetermined angle shift in the circumferential direction. The short-circuit component member group is stacked with the connecting portions of each other being reversed, the outer peripheral side terminals and the inner peripheral side terminals are in contact with each other in the stacking direction, and the connecting portions are not in the stacking direction. A rectifier comprising: a short-circuit member formed as a contact; and a surge absorbing element whose resistance value is changed so as to reduce spark discharge generated between the segment and a power supply brush that is in sliding contact with the segment. A is, the surge absorbing element is in its gist that are integrally molded to the terminal to be interposed between the terminals adjacent to each other in the circumferential direction for electrically connecting the terminal to each other.

  According to this configuration, the surge absorbing element is integrally formed with the terminal so as to be interposed between the terminals adjacent in the circumferential direction. Thus, the surge absorbing element is provided in the commutator with a simple configuration that is simply molded integrally with the terminal. Therefore, since the surge absorbing element can be provided in the commutator without using a clamping piece as in the prior art, the step of providing the surge absorbing element is complicated even when the motor provided with the commutator is multipolarized. And a surge absorbing element can be easily provided. Furthermore, since the surge absorbing element is formed integrally with the terminal, a projection or the like like a conventional connection piece does not have to be formed in the segment in order to provide the surge absorbing element in the commutator. Therefore, it can prevent that a segment becomes a complicated shape, and can suppress the increase in the manufacturing cost of a commutator by extension.

The invention according to claim 2 is characterized in that, in the commutator according to claim 1, the surge absorbing element has an annular shape.
According to this configuration, since the surge absorbing element has an annular shape, the balance of the weight of the commutator rotating in the circumferential direction is maintained. Moreover, the shape of two laminated | stacked short circuit component member groups can be stabilized by an annular | circular shaped surge absorption element.

  A third aspect of the present invention is the commutator according to the first or second aspect, wherein the surge absorbing element is interposed between the inner peripheral side terminals adjacent in the circumferential direction. The gist is that it is integrally formed with the side terminal.

  According to this configuration, the volume of the surge absorbing element can be reduced compared to the case where the surge absorbing element is integrally formed with the same number of outer peripheral terminals as the integrally formed surge absorbing element. As a result, the manufacturing cost can be reduced.

  The invention according to claim 4 includes a plurality of outer peripheral terminals arranged in the circumferential direction and respectively connected to a plurality of segments of the commutator, and a plurality of inner peripheral terminals arranged in the circumferential direction inside the outer peripheral terminal. And two short-circuit constituent member groups each having a plurality of connecting portions that connect the outer peripheral side terminal and the inner peripheral side terminal with a predetermined angle shift in the circumferential direction. The short-circuit member in which the outer peripheral terminals and the inner peripheral terminals are contacted in the stacking direction and the connecting portions are not in contact in the stacking direction, and the terminals adjacent to each other in the peripheral direction The resistance value is changed so as to reduce spark discharge generated between the segment and the power supply brush that is in sliding contact with the segment. In that it comprises a surge absorbing element which has as its gist.

  According to this configuration, the surge absorbing element is integrally formed with the terminal so as to be interposed between the terminals adjacent in the circumferential direction. Therefore, even if the number of terminals is increased, the surge absorbing element has a simple configuration that is simply molded integrally with the terminal, and thus the process of providing the surge absorbing element on the short-circuit member may be complicated. Is prevented. Therefore, the surge absorbing element can be easily provided on the short-circuit member.

  The invention according to claim 5 is a commutator body having a plurality of segments provided in the circumferential direction, a plurality of circumferential terminals arranged in the circumferential direction and respectively connected to the segments, and a circumferential direction inside the outer circumferential terminal. Two short-circuit constituting member groups each having a plurality of inner peripheral terminals arranged on the outer peripheral side, and a plurality of connecting portions that connect the outer peripheral terminal and the inner peripheral terminal with a predetermined angle shift in the circumferential direction. The connecting portions are stacked in the opposite direction, the outer peripheral terminals and the inner peripheral terminals are contacted in the stacking direction, and the connecting portions are not contacted in the stacking direction. And a surge absorbing element whose resistance value changes so as to reduce spark discharge generated between the segment and a power supply brush that is in sliding contact with the segment, and a method of manufacturing a commutator comprising: Solidified by heat treatment after pressure forming so that the powder material to be a surge absorbing element is interposed between the terminals adjacent to each other in the circumferential direction of the two laminated short circuit component groups and the terminals are connected to each other The gist of the invention is that it includes a surge absorbing element molding step for integrally molding the surge absorbing element in the terminal.

  According to the same configuration, the surge absorbing element is integrally formed on the terminal by a simple method of pressure-molding and heat-treating the powder material to be the surge absorbing element. Therefore, since the surge absorbing element can be provided in the commutator without using a clamping piece as in the prior art, the step of providing the surge absorbing element is complicated even when the motor provided with the commutator is multipolarized. Is prevented. As a result, the surge absorbing element can be easily provided.

  The invention according to claim 6 is the method of manufacturing a commutator according to claim 5, wherein, in the surge absorbing element forming step, the surge absorbing element is formed in an annular shape, and after the surge absorbing element forming step, The gist of the invention is that it includes an insulating portion molding step of filling the molten insulating resin material between the connecting portions facing each other in the stacking direction and curing the insulating resin material to form an insulating portion.

  According to this configuration, since the surge absorbing element is formed in an annular shape, the manufactured commutator maintains a good balance of weight when rotating in the circumferential direction. Further, when the surge absorbing element is formed in an annular shape, the shape of the two short-circuit constituent member groups stacked can be stabilized. Therefore, in the insulating part forming step, when the molten insulating resin material is filled between the connecting parts facing in the stacking direction, the connecting part is deformed or the position of the connecting part is changed by the resin resin to be filled. This prevents the resin material from being filled. Moreover, in an insulation part formation process, it is suppressed that a connection part contacts and is short-circuited. Furthermore, when the shapes of the two stacked short-circuit component members are stabilized, the process of connecting the outer peripheral terminal to the segment to fix the short-circuit member to the commutator body is facilitated.

  ADVANTAGE OF THE INVENTION According to this invention, the commutator which can provide a surge absorption element easily, the short circuit member with which this commutator is equipped, and the manufacturing method of this commutator can be provided.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings.
First, the configuration of the motor of this embodiment will be described.
As shown in FIGS. 1 and 2, the motor 101 has an armature 103 disposed inside a stator 102. The yoke housing 104 constituting the stator 102 has a bottomed cylindrical shape, and six permanent magnets 105 are fixed to the inner peripheral surface thereof at equal angular intervals in the circumferential direction. The opening of the yoke housing 104 is closed by a substantially disc-shaped end frame 106, and the end frame 106 includes an anode brush B1 and a cathode brush as power supply brushes connected to an external power supply device. B2 is held.

  The armature 103 is disposed inside the six permanent magnets 105. A rotating shaft 107 constituting the armature 103 is rotatably supported by bearings 108a and 108b fixed to the center of the bottom of the yoke housing 104 and the center of the end frame 106, respectively. One end of the rotating shaft 107 on the end frame side protrudes from the center of the end frame 106 toward the outside of the yoke housing 104.

  An armature core K is fixed to the rotary shaft 107 at a position facing the permanent magnet 105 in the radial direction. The armature core K has eight teeth T1 to T8 extending radially along the radial direction of the rotating shaft 107, and coils M1 to M8 as armature coils are respectively provided in the teeth T1 to T8. It is wound in a concentrated volume.

  Further, a commutator C1 to which both ends of the coils M1 to M8 are connected is fixed to the rotating shaft 107 at a position between the end frame 106 and the armature core K. The commutator C1 includes a commutator body 41 fixed to the rotating shaft 107, and a short-circuit member 42 fixed to one end (left end in FIG. 2) of the commutator body 41 in the axial direction. It is configured.

  As shown in FIGS. 3A and 5, the commutator body 41 includes a substantially cylindrical insulator 43 made of an insulating resin material, and a substantially rectangular plate fixed to the outer peripheral surface of the insulator 43. It is composed of 24 segments 1 to 24 having a shape. The lower end surface of the insulator 43 in FIG. 3 is formed in parallel with a plane orthogonal to the central axis of the insulator 43.

  The 24 segments 1-24 are arrange | positioned on the outer peripheral surface of the insulator 43 so that it may have a clearance gap between the segments adjacent to the circumferential direction, and may become equiangular space | interval in the circumferential direction. Then, the anode side brush B1 and the cathode side brush B2 are slidably contacted with these segments 1 to 24 from the outside in the radial direction (see FIG. 2).

  A pair of caulking convex portions 45a and 45b extending in the axial direction from the lower end are juxtaposed in the circumferential direction at the lower end of each segment 1 to 24 in FIG. 3A (see FIG. 4). In a state where the segments 1 to 24 are fixed to the outer peripheral surface of the insulator 43, the caulking convex portions 45a and 45b protrude downward from the lower end surface of the insulator 43 in FIG.

The short-circuit member 42 includes first and second short-circuit constituent member groups 51 and 52 that are formed by punching a conductive material (for example, a copper plate) and have the same shape.
As shown in FIG. 6, the first and second short-circuit constituting member groups 51 and 52 are each composed of 24 (that is, the same number as the segments 1 to 24) outer peripheral side terminals 51a, 52a. All the 24 outer peripheral terminals 51a have the same substantially rectangular shape, and the circumferential width thereof is the distance L1 between the pair of caulking convex portions 45a and 45b formed in each of the segments 1 to 24, respectively. (See FIG. 4).

  On the other hand, of the 24 outer peripheral terminals 52a, if eight outer peripheral terminals 52a arranged at equal angular intervals in the circumferential direction are first outer peripheral terminals 61, these eight first outer peripheral terminals The terminal 61 has the same shape as the outer peripheral side terminal 52 a of the first short-circuit component group 51. Of the 24 outer peripheral terminals 52a, if a total of 16 outer peripheral terminals 52a arranged two by two between the first outer peripheral terminals 61 are defined as the second outer peripheral terminals 62, the second outer peripheral terminals 62 is formed longer toward the radially outer side than the first outer peripheral side terminal 61. The circumferential width of the second outer peripheral terminal 62 is formed to be equal to the circumferential width of the first outer peripheral terminal 61, and the coils M <b> 1 to M <b> 8 are formed at the distal end portion of the second outer peripheral terminal 62. In a state before winding, a folded piece 62a extending in parallel with the axial direction is provided. As shown in FIG. 4, the total thickness when the outer peripheral side terminals 51a and 52a are laminated in the plate thickness direction is formed to be thinner than the length of the caulking convex portions 45a and 45b in the protruding direction. Yes.

  As shown in FIG. 6, 24 (that is, the same number as the segments 1 to 24) inner peripheral side terminals constituting the first short-circuit component member group 51 are disposed inside the outer peripheral side terminals 51 a and 52 a arranged in the circumferential direction. 51b are arranged at equal angular intervals in the circumferential direction. Similarly, on the inner side of the outer peripheral side terminals 51a and 52a, 24 inner peripheral side terminals 52b constituting the second short circuit component group 52 (that is, the same number as the segments 1 to 24) are equiangularly spaced in the circumferential direction. Is arranged. The inner peripheral terminals 51b and 52b are arranged so that their circumferential positions are equal to the outer peripheral terminals 51a and 52a, and the radially outer peripheral terminals 51a and 52a and the inner peripheral terminal 51b are opposed to each other in the radial direction. , 52b coincides with the respective center lines that pass through the center in the circumferential direction and extend in the radial direction.

  In the first short circuit component group 51, the outer peripheral side terminal 51a and the inner peripheral side terminal 51b are connected to each other with a predetermined angle shift by a connecting part 51c formed along an involute curve. Similarly, in the second short-circuit constituting member group 52, the outer peripheral side terminal 52a and the inner peripheral side terminal 52b are connected with a predetermined angle shifted by a connecting part 52c formed along an involute curve. In the present embodiment, the predetermined angle is 60 °, which is equal to an angle obtained by shifting the terminal by four. And the outer peripheral side terminal 51a, the inner peripheral side terminal 51b, and the connection part 51c which comprise the 1st short circuit component group 51 are formed in the same plane, and the outer periphery side which comprises the 2nd short circuit component group 52 The terminal 52a, the inner peripheral terminal 52b, and the connecting portion 52c are also formed in the same plane. As shown in FIG. 3B, each connecting portion 51c has one surface in the thickness direction of the connecting portion 51c and one of the outer peripheral side terminal 51a and the inner peripheral side terminal 51b corresponding to each connecting portion 51c. It is formed thinner than the outer peripheral side terminal 51a and the inner peripheral side terminal 51b so that a step 51d is formed by the side surface. Similarly, each connecting portion 52c is stepped by a surface on one side in the plate thickness direction of the connecting portion 52c and a surface on one side of the outer peripheral side terminal 52a and the inner peripheral side terminal 52b corresponding to each connecting portion 52c. It is formed thinner than the outer peripheral side terminal 52a and the inner peripheral side terminal 52b so that 52d is formed. By the way, in this embodiment, “coplanar” means that even if there are some irregularities (steps), each part is layered when stacked in the thickness direction (each part does not enter the axial direction). Means shape.

  As shown in FIG. 6, the first and second short circuit component groups 51 and 52 as described above include the connecting portion 51 c of the first short circuit component group 51 and the second short circuit component group 52 as viewed from the axial direction. The connecting portions 52c are stacked in the thickness direction so as to be opposite to each other. That is, in the first and second short-circuit constituent member groups 51 and 52, the directions in which the outer peripheral side terminals 51a and 52a and the inner peripheral side terminals 51b and 52b are connected by the connecting portions 51c and 52c are opposite to each other in the circumferential direction. It is laminated in the axial direction so as to be oriented. In the laminated first and second short circuit component groups 51 and 52, the outer peripheral side terminal 51a of the first short circuit component group 51 and the outer peripheral terminal 52a of the second short circuit component group 52 are laminated to each other. While contacting, the inner peripheral side terminal 51b of the 1st short circuit component group 51 and the inner peripheral side terminal 52b of the 2nd short circuit component group 52 are mutually laminated | stacked, and surface contact is carried out. On the other hand, the connection part 51c of the 1st short circuit component group 51 and the connection part 52c of the 2nd short circuit structure member group 52 form the level | step differences 51d and 52d, respectively, and the outer peripheral side terminals 51a and 52a and the inner peripheral side terminal 51b. , 52b is formed so as to be thinner than the other, 52b in a non-contact manner in the stacking direction (axial direction in the present embodiment). The laminated outer peripheral terminals 51a and 52a and the laminated inner peripheral terminals 51b and 52b are integrated by spot welding or the like.

  As shown in FIG. 5, in the laminated first and second short circuit component groups 51 and 52, annular varistors 71 are integrally formed on 24 sets of inner peripheral terminals 51b and 52b that are in contact with each other in the lamination direction. Has been. Specifically, the varistor 71 covers a portion of each inner peripheral terminal 51b, 52b excluding the surface that contacts each other, and is interposed between the inner peripheral terminals 51b, 52b adjacent to each other in the circumferential direction. The peripheral terminals 51b and 52b are electrically connected to each other. The varistor 71 normally has a higher resistance value than the coils M1 to M8, but has a characteristic that the resistance value decreases rapidly when an applied voltage exceeding a certain level is applied.

  Further, in the stacked first and second short circuit component groups 51 and 52, a portion from the radially outer surface of the varistor 71 to the middle of the stacked outer peripheral side terminals 51a and 52a is an annular insulating portion. 72. The insulating portion 72 is made of an insulating resin material, and the gap between the connecting portions 51c and 52c adjacent in the circumferential direction, and the connecting portion 51c of the first short-circuit constituting member group 51 and the second short-circuit constituting member group. The gap between 52 and the connecting portion 52c is filled. As shown in FIG. 3, the end face on the insulator 43 side in the insulating portion 72 is formed to be flush with the end face on the insulator 43 side in the varistor 71. The end surface of the insulator 72 on the insulator 43 side and the end surface of the varistor 71 on the insulator 43 side are orthogonal to the central axis of the insulator 43 so as to correspond to the lower end surface of the insulator 43 in FIG. Is formed.

  The short-circuit member 42 is disposed at the lower end of the commutator body 41, and the outer peripheral side terminals 51a and 52a are caulked by the pair of caulking convex portions 45a and 45b provided in the segments 1 to 24, respectively. It is fixed to the commutator body 41. Then, the segments 1 to 24 and the short-circuit member 42 are electrically connected by the caulking convex portions 45 a and 45 b forming a pair of the outer peripheral side terminals 51 a and 52 a, and the segment having the same potential by the short-circuit member 42. 1 to 24 are short-circuited. Incidentally, the short circuit member 42 has short-circuited three segments arrange | positioned in the position which becomes a 120 degree space | interval in the circumferential direction, respectively. That is, as shown in FIG. 7, the short-circuit member 42 short-circuits the segments 1, 9 and 17, short-circuits the segments 2, 10 and 18, and further short-circuits the segments 3, 11 and 19. The short-circuit member 42 short-circuits the segments 4, 12, and 20, shorts the segments 5, 13, and 21, and further short-circuits the segments 6, 14, and 22. Further, the short-circuit member 42 short-circuits the segments 7, 15 and 23 and short-circuits the segments 8, 16 and 24. Then, the short-circuit member 42 fixed to the commutator body 41 causes the second outer peripheral side terminal 62 to protrude radially outward from the outer peripheral surface of the segments 1 to 24 fixed to the outer peripheral surface of the insulator 43. ing. In the state where the short-circuit member 42 is fixed to the commutator body 41, the central axis of the varistor 71 and the central axis of the insulator 43 coincide with each other.

  In the present embodiment, in the first and second short circuit component groups 51 and 52, two inner peripheral terminals 51b and 52b adjacent in the circumferential direction and two outer peripheral terminals connected by the connecting portions 51c and 52c. Since 51a and 52a are adjacent to each other in the circumferential direction, the segments connected to the two outer peripheral terminals 51a and 52a are adjacent to each other in the circumferential direction. Furthermore, the varistor 71 is provided so as to be electrically interposed between the inner peripheral terminals 51b and 52b adjacent in the circumferential direction. For these reasons, when the short-circuit member 42 is fixed to the commutator body 41, the first and second short-circuit constituent member groups 51 and 52 are disposed between any two segments 1 to 24 adjacent in the circumferential direction. Thus, the varistor 71 is electrically interposed.

  In the commutator C <b> 1 configured as described above, the end portions of the corresponding coils M <b> 1 to M <b> 8 are connected to the second outer peripheral side terminals 62. That is, it corresponds to each of the second outer peripheral side terminals 62 provided corresponding to the eight pairs of segments 2, 3, 5, 6,..., 20, 21, 23, 24 that are adjacent to each other in the circumferential direction. The ends of the coils M1 to M8 are connected. For example, the end portions of the coil M1 are connected to the second outer peripheral side terminals 62 corresponding to the segments 2 and 3 that are adjacent to each other in the circumferential direction, so that the end portion of the coil M1 is connected to the segments 2 and 3. Are electrically connected. The end portions of the coils M1 to M8 are formed on the second outer peripheral side by folding the folded piece 62a toward the center side in the radial direction of the commutator C1 after the coils M1 to M8 are wound around the teeth T1 to T8. While being pinched by the terminal 62, it is joined to the second outer peripheral side terminal 62 by fusing or the like.

  In the motor 101 of the present embodiment configured as described above, when current is selectively supplied from the external power supply device to the coils M1 to M8 via the anode side brush B1 and the cathode side brush B2, the coils M1 to M1 are supplied. The armature 103 rotates according to the rotating magnetic field generated at M8. When the armature 103 rotates, the commutator C1 rotates, so that the coils M1 to M8 are sequentially rectified by the anode side brush B1 and the cathode side brush B2 that are in sliding contact with the segments 1 to 24 of the commutator C1. At this time, when a high voltage is to be generated between the two segments connected to both ends of the coil being rectified and the brush, the resistance value of the varistor 71 electrically interposed between the two segments is The value becomes small so as to reduce the spark discharge generated between the brush and the current, and the current flows through the varistor 71. Thereby, the voltage between the two segments to which both ends of the coil being rectified are connected and the brush is lowered, and spark discharge is suppressed. When the voltage between the two segments connected to both ends of the coil being rectified and the brush is lowered, the resistance value of the varistor 71 returns to a value higher than the resistance value of the coil.

Next, the manufacturing method of the commutator of this embodiment is demonstrated.
First, the punching process which forms the 1st and 2nd short circuit component group 51,52 is performed. In this punching step, the first and second short circuit component groups 51 and 52 are each formed by punching a conductive plate material (for example, a copper plate) with a punch (both not shown). When the outer peripheral terminals 51a and 52a, the inner peripheral terminals 51b and 52b, and the connecting parts 51c and 52c are punched out, the connecting parts 51c and 52c are simultaneously formed thin to form steps 51d and 52d.

  Next, a laminating process is performed in which the first and second short circuit component groups 51 and 52 formed by punching are stacked. In this laminating step, the first short circuit component group 51 and the second short circuit component group 52 are viewed from the thickness direction of the first short circuit component group 51 and the second short circuit component group 51c. The connection parts 52c of 52 are laminated so as to be opposite to each other. Then, the corresponding outer peripheral terminals 51a and 52a and the corresponding inner peripheral terminals 51b and 52b are contacted by being stacked. At this time, since the first and second short-circuit constituting member groups 51 and 52 are formed with steps 51d and 52d, the connecting portions 51c and 52c are not in contact with each other in the stacking direction and are connected in the stacking direction. A gap is formed between 51c and 52c. And the laminated | stacked outer peripheral side terminals 51a and 52a, and the laminated | stacked inner peripheral side terminals 51b and 52b are integrated by spot welding, As shown in FIG. 6, the 1st short circuit component member group 51 is shown. And the second short circuit component group 52 are integrated.

  Next, a varistor molding step (surge absorbing element molding step) for forming the varistor 71 by sintering is performed. In this varistor forming step, the integrated first and second short-circuit constituting member groups 51 and 52 are arranged in a mold (not shown), and a powder material (for example, strontium titanate powder) that becomes the varistor 71 is provided. ) In a mold. The powder material filled in the mold covers the portions of the inner peripheral terminals 51b and 52b excluding the surfaces that contact each other, and is interposed between the inner peripheral terminals 51b and 52b adjacent in the circumferential direction. The inner peripheral terminals 51b and 52b adjacent to each other in the direction are annular. Then, by pressing the powder material and heat-treating the powder material at a temperature not higher than the melting point of the powder material, the powder material is solidified to form an annular varistor 71 as shown in FIG. It is integrally formed with the inner peripheral side terminals 51b and 52b. The formed varistor 71 electrically connects the inner peripheral side terminals 51b and 52b adjacent in the circumferential direction.

  Next, an insulating part forming step for forming the insulating part 72 is performed. In this insulating portion forming step, the first and second short-circuit constituting member groups 51 and 52 in which the varistor 71 is formed are arranged in the forming die for forming the insulating portion 72, and then the molten insulating resin material is used in the same forming die. Fill inside. At this time, in the first and second short-circuit constituting member groups 51 and 52, the part from the radially outer surface of the varistor 71 to the middle of the laminated outer peripheral side terminals 51a and 52a is covered with the molten insulating resin material. Is called. At the same time, the resin material melted in the gap between the connecting portions 51 c and 52 c adjacent in the circumferential direction and the gap between the connecting portion 51 c of the first short-circuit constituting member group 51 and the connecting portion 52 c of the second short-circuit constituting member group 52. Is filled. Then, the insulating resin material is cooled and cured to form the insulating portion 72, and the short-circuit member 42 is completed. The short-circuit member 42 is taken out from the mold after the insulating portion 72 is formed.

  Next, an assembly process in which the short-circuit member 42 is assembled to the commutator body 41 is performed. In this assembling step, the short-circuit member 42 is disposed at the lower end of the commutator body 41, and at the same time, the corresponding outer peripheries between the pair of caulking convex portions 45a and 45b formed at the lower ends of the segments 1 to 24, respectively. Side terminals 51a and 52a are arranged. And a force is applied and caulked so that a pair of caulking convex part 45a, 45b may mutually approach the circumferential direction, and the outer peripheral side terminals 51a and 52a and the segments 1-24 are connected. Thereby, the short-circuit member 42 is fixed with respect to the commutator body 41, and the commutator C1 is completed.

As described above, the present embodiment has the following effects.
(1) In the laminated first and second short-circuit component members 51 and 52, the varistor 71 is arranged between the inner peripheral terminals 51b and 52b so as to be interposed between the inner peripheral terminals 51b and 52b adjacent in the circumferential direction. Are integrally molded. Thus, the varistor 71 is provided in the commutator C1 with a simple configuration that is simply formed integrally with the inner peripheral terminals 51b and 52b.

  In the varistor molding process, the varistor 71 interposes the powder material that becomes the varistor 71 between the inner peripheral terminals 51b and 52b adjacent in the circumferential direction, and the inner peripheral terminals 51b and 52b adjacent in the circumferential direction. After being pressure-molded so as to be connected, heat treatment is performed and solidified to integrally form the inner peripheral terminals 51b and 52b. As described above, the varistor 71 is integrally formed with the inner peripheral terminals 51b and 52b by a simple method in which the powder material is pressed and heat-treated.

  From these facts, since the varistor 71 can be provided in the commutator C1 without using a clamping piece as in the prior art, the motor 101 is more multipolar than a motor having two permanent magnets and three coils. However, the process of providing the varistor 71 is prevented from becoming complicated. As a result, the varistor 71 can be easily provided on the commutator C1.

  (2) Since the varistor 71 is formed integrally with the inner peripheral terminals 51b and 52b, a projection or the like like a conventional connection piece is formed in the segments 1 to 24 in order to provide the varistor 71 in the commutator C1. You don't have to. Therefore, the segments 1 to 24 can be prevented from having a complicated shape, and as a result, an increase in manufacturing cost of the commutator C1 can be suppressed.

  (3) In the varistor 71, the center axis of the varistor 71 and the center axis of the insulator 43 coincide with each other in a state where the short-circuit member 42 is fixed to the commutator body 41. Therefore, the weight balance of the commutator C1 rotating in the circumferential direction is maintained. Further, when the varistor 71 is formed in an annular shape, the shape of the stacked first and second short-circuit constituting member groups 51 and 52 is easily stabilized. Therefore, in the insulating part molding process performed after the varistor molding process, when the molten insulating resin material is filled between the coupling parts 51c and 52c facing each other in the stacking direction, the coupling parts 51c and 52c are deformed by the filled resin material. And the positions of the connecting portions 51c and 52c are prevented from changing, and the resin material can be easily filled. In addition, in the insulating portion forming step, the connecting portions 51c and 52c are prevented from coming into contact with each other and being short-circuited. Furthermore, since the shapes of the stacked first and second short circuit component groups 51 and 52 are stabilized, it is easy to perform an assembly process of assembling the short circuit member 42 to the commutator body 41.

  (4) The varistor 71 includes inner peripheral terminals 51b and 52b so as to be interposed between the inner peripheral terminals 51b and 52b adjacent in the circumferential direction in the stacked first and second short circuit component groups 51 and 52. Are integrally molded. Therefore, in the laminated first and second short circuit component groups 51 and 52, the volume of the varistor can be smaller than that in the case where the varistor is integrally formed so as to form an annular shape on the outer peripheral side terminals 51a and 52a. As a result, the amount of powder material to be used can be reduced and the manufacturing cost can be reduced as compared with the case where the varistors are integrally formed on the outer peripheral side terminals 51a and 52a.

  (5) Since the insulating portion 72 is provided so as to fill a gap between the connecting portions 51c and 52c facing in the stacking direction, the non-contact state between the connecting portions 51c and 52c facing in the stacking direction is the insulating portion. 72 makes it more reliable and prevents the connection portions 51c and 52c from being short-circuited. In addition, the end surface on the insulator 43 side in the insulating portion 72 is formed to be flush with the end surface on the insulator 43 side in the varistor 71, and the end surface on the insulator 43 side in the insulating portion 72 and the end surface on the varistor 71. The end face on the insulator 43 side is formed to be orthogonal to the central axis of the insulator 43 so as to correspond to the lower end face of the insulator 43 in FIG. Accordingly, in the assembling process, the short-circuit member 42 is stably disposed at the lower end of the commutator body 41 by the surface of the insulator 43 side of the varistor 71 and the insulating portion 72 coming into contact with the lower end surface of the insulator 43. Is done. As a result, the short-circuit member 42 can be more easily assembled to the commutator body 41.

In addition, you may change embodiment of this invention as follows.
-It may replace with the varistor 71 of the said embodiment, and may provide the varistor 81 shown to Fig.9 (a) (b) and FIG. 10 in a short circuit member. In FIGS. 9A, 9B, and 10, the same components as those in the above embodiment are denoted by the same reference numerals. The varistor 81 provided in the short-circuit member 80 shown in FIGS. 9A and 10 is integrally formed with 24 sets of outer peripheral terminals 51a and 52a that are in contact with each other in the stacking direction. The varistor 81 has an annular shape, covers a portion of each outer peripheral side terminal 51a, 52a excluding the contact surface with each other, and is adjacent to the circumferential direction by being interposed between the outer peripheral side terminals 51a, 52a adjacent to each other in the circumferential direction. The outer peripheral terminals 51a and 52a are electrically connected to each other. In the short-circuit member 80, the insulating portion 82 made of an insulating resin material has an annular shape covering the inner peripheral terminals 51b and 52b from the radially inner surface of the varistor 81. As shown in FIG. 9B, the insulating portion 82 is similar to the insulating portion 72 of the above-described embodiment, and includes a gap between the connecting portions 51c and 52c adjacent in the circumferential direction, and the first short-circuit constituting member group 51. The gap between the connecting portion 51c of the second short-circuit component member group 52 and the connecting portion 52c of the second short-circuit constituting member group 52 is filled. The commutator C2 provided with such a short-circuit member 80 is also manufactured by the manufacturing method of the above embodiment, similarly to the commutator C1. Even if comprised in this way, the effect similar to (1) thru | or (3) of the effect | action and effect of the said embodiment can be acquired. The short circuit member 42 of the above embodiment may further include the varistor 81 described above.

  In the above embodiment, the annular varistor 71 is integrally formed on all the 24 sets of the inner peripheral side terminals 51b and 52b that are stacked. However, if the varistor 71 is electrically interposed between any two segments 1 to 24 that are adjacent to each other in the circumferential direction via the short-circuit member 42, the predetermined number of the 24 sets of inner peripheral side terminals 51 b and 52 b is predetermined. The varistor may be integrally formed only on the inner peripheral side terminals 51b and 52b. For example, in the motor 101, five sets of inner peripheral terminals 51b and 52b arranged continuously in the circumferential direction and one point on the central axis line of the insulator 43 with respect to the five sets of inner peripheral terminals 51b and 52b. A varistor may be integrally formed with each of the five sets of inner peripheral terminals 51b and 52b disposed at positions that are point-symmetric with respect to the center. In the motor 101, a varistor may be integrally formed only on the nine sets of inner peripheral terminals 51b and 52b arranged continuously in the circumferential direction. Note that the same can be said when the outer peripheral terminals 51a and 52a are integrally configured as in the examples shown in FIGS. If comprised in this way, the volume of the varistor to be used can be reduced more, and a reduction in manufacturing cost can be aimed at by extension.

  In the above embodiment, the varistor 71 has an annular shape, but is not limited thereto. For example, the varistor 71 may be formed in an annular shape having a polygonal shape as viewed from the axial direction.

The short circuit member 42 may be configured without the insulating portion 72. Further, the insulating part 72 may be provided only between the connecting parts 51c and 52c facing each other in the stacking direction.
In the varistor molding process, temperature control may be performed so that the surfaces of the inner peripheral terminals 51b and 52b except the surfaces that contact each other are welded to the varistor 71 during the heat treatment. If it does in this way, the reliability of the electrical connection between the inner peripheral side terminals 51b and 52b and the varistor 71 can be improved.

  In the above embodiment, the varistor forming process is performed after the lamination process. However, the brazing material is plated on the surface of the portion (inner peripheral side terminal 51b, 52b) where the varistor 71 is integrally formed in the first and second short-circuit constituting member groups 51, 52 between the lamination step and the varistor forming step. A plating step may be added. If it does in this way, since it becomes easy to join the varistor 71 and the surface of inner peripheral side terminal 51b, 52b with a wax material, the reliability of the electrical connection between inner peripheral side terminal 51b, 52b and the varistor 71 is reliable. Can be improved.

  -In above-mentioned embodiment, although all the connection parts 51c and 52c are formed along the involute curve, they may comprise circular arc shape and linear form. Moreover, in the said embodiment, although the outer peripheral side terminals 51a and 52a and the inner peripheral side terminals 51b and 52b have comprised substantially rectangular shape, circular shape etc. may be sufficient.

  In the above embodiment, the end portions of the corresponding coils M1 to M8 are connected to the second outer peripheral side terminal 62, respectively. However, while forming the 1st outer peripheral side terminal 61 in the same shape as the 2nd outer peripheral side terminal 62 of the above-mentioned embodiment, the 2nd outer peripheral side terminal 62 is formed in the same shape as the 1st outer peripheral side terminal of the above-mentioned embodiment, It is good also as a structure by which the edge part of corresponding coil M1-M8 is connected to the 1st outer peripheral side terminal 61, respectively. In this case, the end portions of the two coils are connected to one first outer peripheral side terminal 61.

  -In the said embodiment, although the varistor 71 was used as a surge absorption element for reducing the spark discharge produced between the segments 1-24 and the anode side brush B1 and the cathode side brush B2 which are slidably contacted with this segment, A surge absorbing element other than a varistor, which can be manufactured by the manufacturing method of the above embodiment, may be used.

  In the above embodiment, the motor 101 includes six permanent magnets 105, eight coils M1 to M8, and 24 segments 1 to 24. However, the number of permanent magnets, the number of coils, and the number of segments are not limited to this, and may be changed as appropriate.

The technical idea that can be grasped from the above embodiment and each of the above modifications will be described below.
(A) In the method of manufacturing a commutator according to claim 5 or claim 6, in the surge absorbing element forming step, the powder material and a surface of the terminal in contact with the powder material are welded. The method of manufacturing a commutator is characterized in that the heat treatment is performed with the temperature controlled. If it does in this way, the reliability of the electrical connection between a terminal and a surge absorption element can be improved.

  (B) In the method of manufacturing a commutator according to claim 5 or 6, a plating step of plating a surface of the terminal with which the powder material contacts with a brazing agent before the surge absorbing element forming step. A method of manufacturing a commutator, comprising: If it does in this way, the reliability of the electrical connection between a terminal and a surge absorption element can be improved.

The radial direction sectional view of a motor. The axial sectional view of a motor. (A) is an axial sectional view of the commutator, (b) is a partially enlarged view in FIG. The elements on larger scale of the commutator which show the connection state of an outer peripheral side terminal and a segment. The bottom view of a commutator. The top view of a short circuit component member group. Motor connection diagram. The top view of the short circuit component member group of the state by which the varistor was integrally molded. (A) is an axial sectional view of a commutator according to another embodiment, and (b) is a partially enlarged view of FIG. The bottom view of the commutator of another form.

Explanation of symbols

  1-24 ... segment, 41 ... commutator body, 42, 80 ... short circuit member, 51 ... first short circuit component group as short circuit component group, 52 ... second short circuit component group as short circuit component group, 51a , 52a ... outer peripheral side terminal, 51b, 52b ... inner peripheral side terminal, 51c, 52c ... connecting part, 71, 81 ... varistor as surge absorbing element, 72, 82 ... insulating part, B1 ... anode side brush as power supply brush B2 ... Cathode side brush as power feeding brush, C1, C2 ... Commutator, M1-M8 ... Coil as armature coil.

Claims (6)

A commutator body having a plurality of segments provided in the circumferential direction;
A plurality of peripheral terminals arranged in the circumferential direction and connected to the segments; inner peripheral terminals arranged in the circumferential direction inside the outer peripheral terminal; the outer peripheral terminals and the inner peripheral terminals; Two short-circuit component members each having a plurality of connecting portions that are connected to each other while being shifted by a predetermined angle in the circumferential direction are stacked so that the connecting portions are opposite to each other, and the outer peripheral side terminals and the inner peripheral side are stacked. The terminals are contacted in the stacking direction and the connecting parts are non-contacted in the stacking direction,
A surge absorbing element whose resistance value changes so as to reduce a spark discharge generated between the segment and a power supply brush that is in sliding contact with the segment;
A commutator comprising
The commutator, wherein the surge absorbing element is integrally formed with the terminals so as to be interposed between the terminals adjacent in the circumferential direction and to electrically connect the terminals. The commutator according to claim 1,
The commutator is characterized in that the surge absorbing element has an annular shape. In the commutator according to claim 1 or 2,
The commutator, wherein the surge absorbing element is integrally molded with the inner peripheral terminal so as to be interposed between the inner peripheral terminals adjacent in the circumferential direction. A plurality of peripheral terminals arranged in the circumferential direction and connected to a plurality of segments of the commutator, a plurality of inner peripheral terminals arranged in the circumferential direction inside the outer peripheral terminal, the outer peripheral terminals, and the inner circumference Two short-circuit component members each having a plurality of connecting portions that are connected to each other by shifting the side terminals by a predetermined angle in the circumferential direction are stacked with the connecting portions reversed, and The inner peripheral terminals are contacted in the stacking direction and the connecting parts are non-contacted in the stacking direction,
Spark discharge generated between the segment and a power supply brush that is slidably contacted with the segment is formed integrally with the terminal so as to be electrically connected between the terminals interposed between the terminals adjacent in the circumferential direction. A short-circuit member comprising a surge absorbing element whose resistance value is changed so as to be reduced. A commutator body having a plurality of segments provided in the circumferential direction;
A plurality of peripheral terminals arranged in the circumferential direction and connected to the segments; inner peripheral terminals arranged in the circumferential direction inside the outer peripheral terminal; the outer peripheral terminals and the inner peripheral terminals; Two short-circuit component members each having a plurality of connecting portions that are connected to each other while being shifted by a predetermined angle in the circumferential direction are stacked so that the connecting portions are opposite to each other, and the outer peripheral side terminals and the inner peripheral side are stacked. The terminals are contacted in the stacking direction and the connecting parts are non-contacted in the stacking direction,
A surge absorbing element whose resistance value changes so as to reduce a spark discharge generated between the segment and a power supply brush that is in sliding contact with the segment;
A method of manufacturing a commutator comprising:
After the powder material to be the surge absorbing element is interposed between the terminals adjacent to each other in the circumferential direction of the two laminated short circuit component groups and is pressure-formed so as to connect the terminals, heat treatment is then performed. A commutator manufacturing method comprising a surge absorbing element forming step of solidifying and integrally forming the surge absorbing element in the terminal. In the manufacturing method of the commutator according to claim 5,
In the surge absorbing element molding step, the surge absorbing element is molded into an annular shape,
After the surge absorbing element molding step, an insulating portion molding step is provided in which the insulating resin material is melted between the connecting portions facing in the stacking direction and the insulating resin material is cured to form an insulating portion. A method of manufacturing a commutator characterized by the above.

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