JP2016134999A - Electric motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric motor which inhibits resonance of a rotary shaft when a brush contacting with a commutator vibrates.SOLUTION: An electric motor includes: a cylindrical commutator 26 attached to an outer peripheral surface of a rotary shaft 22; and a brush 52 configured to contact with the commutator 26 and through which electric current flows. The electric motor has: a cylindrical elastic member 37 disposed between the rotary shaft 22 and the commutator 26; outer recessed parts and outer protruding parts which are formed on an outer peripheral surface of the elastic member 37; and inner recessed parts and inner protruding parts formed on an inner peripheral surface of the elastic member 37.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an electric motor in which a commutator is provided on a rotating shaft.

  Conventionally, in-vehicle electrical equipment such as a wiper device, a power window device, and a power sliding door device is mounted on a vehicle. This in-vehicle electrical equipment has an electric motor as a power source. An example of an electric motor used for in-vehicle electrical equipment is described in Patent Document 1. An electric motor described in Patent Document 1 includes a cylindrical yoke, a magnet fixed to the inner peripheral surface of the yoke, a rotating shaft disposed in the yoke, an armature provided on the rotating shaft, and a rotating shaft. And a cylindrical commutator connected to the armature coil, a housing fixed to the yoke, a brush provided in the housing, and a spring for pressing the brush against the outer peripheral surface of the commutator. A rubber elastic member is provided between the commutator and the rotating shaft.

  In the electric motor described in Patent Document 1, a current is supplied to the armature through the brush and the commutator to form a rotating magnetic field, and the rotating shaft rotates. The commutator rotates with the rotating shaft, and when vibration occurs at the contact portion between the brush and the commutator, the elastic member absorbs the vibration. For this reason, it describes that the vibration of a rotating shaft can be suppressed. A technique for suppressing the vibration of the rotating shaft to which the commutator is attached is also described in Patent Document 2.

JP 2002-153014 A JP-A-7-115751

  However, in the electric motors described in Patent Documents 1 and 2, the elastic member is in close contact with the outer peripheral surface of the rotating shaft and the inner peripheral surface of the commutator. For this reason, the amount of elastic deformation of the elastic member is small when the brush vibrates, and the rotating shaft may resonate due to the vibration of the brush.

  The objective of this invention is providing the electric motor which can suppress the resonance of a rotating shaft, when the brush which contacts a commutator vibrates.

  The present invention is an electric motor comprising: a cylindrical commutator attached to an outer peripheral surface of a rotating shaft; and a brush that contacts the commutator and supplies current to the commutator. A cylindrical elastic member arranged between the commutator, an outer concave portion and an outer convex portion formed on the outer peripheral surface of the elastic member, an inner concave portion and an inner convex portion formed on the inner peripheral surface of the elastic member, Have

  In the present invention, the outer concave portion and the outer convex portion are annularly provided along the circumferential direction of the elastic member, and are alternately arranged in the axial direction of the rotating shaft, and the inner concave portion and the inner convex portion. Are annularly provided along the circumferential direction of the elastic member, and are alternately arranged in the axial direction of the rotation shaft.

  The outer concave portion and the outer convex portion in the present invention are inclined with respect to the circumferential direction of the elastic member, and are alternately arranged in the circumferential direction of the elastic member, and the inner concave portion and the inner convex portion are The elastic members are inclined with respect to the circumferential direction, and are alternately arranged in the circumferential direction of the elastic members.

  In the present invention, an armature that forms a rotating magnetic field when current is supplied from a coil is provided in a range different from the commutator in the axial direction of the rotating shaft, and a hook that supports the coil is in the axial direction of the commutator. The elastic member includes a boss portion disposed in a range overlapping the range in which the hook is disposed in the axial direction, and a cylinder disposed in a range different from the boss portion in the axial direction. And the thickness of the boss portion in the radial direction of the rotating shaft exceeds the thickness of the cylindrical portion in the radial direction.

  The elastic member in the present invention is in contact with the outer peripheral surface of the rotating shaft within a range of ½ or more of the total length of the commutator in the axial direction of the rotating shaft.

  The present invention is a wiper device that includes a wiper member that wipes a windshield of a vehicle, and an electric motor that operates the wiper member, and the electric motor includes any of the above-described configurations. Yes.

  According to the present invention, when the commutator rotates with the rotation shaft and the brush vibrates, the elastic member is elastically deformed, and the vibration of the rotation shaft is suppressed. Therefore, the vibration of the brush is hardly transmitted to the rotating shaft, and resonance of the rotating shaft can be suppressed.

It is a bottom view of the drive device provided with the electric motor of the present invention. It is a side view of the drive device provided with the electric motor of the present invention. It is a side view of the commutator of the electric motor of this invention. It is sectional drawing of the commutator of the electric motor of this invention. (A), (B) is explanatory drawing which shows the other example of the elastic member used for an electric motor.

  The electric motor in the present invention is used for in-vehicle electrical equipment such as a vehicle wiper device, a power window device, and a power slide door device. Hereinafter, an embodiment in which an electric motor according to the present invention is used as a power source for operating a wiper member that is an operation member of a wiper device will be described in detail with reference to the drawings.

  The wiper device 10 shown in FIGS. 1 and 2 has a pivot shaft 11 to which a wiper member 64 is attached. The wiper member 64 includes a wiper arm 64A and a blade attached to the wiper arm 64A. The wiper device 10 includes an electric motor 12 that generates power when electric power is supplied, a speed reduction mechanism 13 that is provided in a path that transmits the power of the electric motor 12 to the pivot shaft 11, and a casing 14 that houses the speed reduction mechanism 13. And having.

  The electric motor 12 is mainly disposed outside the casing 14. The electric motor 12 includes a stator assembly 15 as a field and a rotor assembly 16 as an armature. The stator assembly 15 includes a yoke 18 configured in a cylindrical shape, and a plurality of permanent magnets 19 fixed to the inner periphery of the yoke 18. The yoke 18 is fixed to the casing 14 by a screw member.

  The yoke 18 is made of a metal material such as iron. A support cylinder 20 is formed at the first end of the yoke 18 in the direction along the axis A <b> 1, and an opening is formed at the second end of the yoke 18. A bearing 21 is provided in the support cylinder 20. The rotor assembly 16 is rotatable about the axis A1.

  On the other hand, the rotor assembly 16 includes a rotating shaft 22 and an armature 23 that rotates together with the rotating shaft 22. The amateur 23 is obtained by winding a coil 23B around an amateur core 23A. The coil 23B is a conductive member, and a current passes through the coil 23B. About half of the rotation axis 22 in the direction of the axis A <b> 1 is arranged in the yoke 18, and the other half in the longitudinal direction is arranged in the casing 14. The amateur 23 is disposed inside the plurality of permanent magnets 19.

  Further, a worm 24 is formed at a location where the rotary shaft 22 is disposed in the casing 14. A portion corresponding to the space between the armature 23 and the worm 24 is supported by the bearing 25 in the direction along the axis A1 of the rotary shaft 22. The bearing 25 is disposed at a position different from the amateur 23 in the direction along the axis A1. The inner ring of the bearing 25 is fitted and fixed to the outer periphery of the rotating shaft 22.

  Further, a commutator 26 is attached between the bearing 25 and the armature 23 on the rotary shaft 22. As shown in FIGS. 3 and 4, the commutator 26 is obtained by fixing a plurality of conductive steel plates 28 to a main body 27 formed of an insulating material. As the insulating material constituting the main body 27, a thermosetting resin is used. The main body 27 is molded, and a plurality of steel plates 28 are integrated with the main body 27.

  The main body 27 has a cylindrical shape, and the plurality of steel plates 28 are fixed at intervals along the circumferential direction of the main body 27. The commutator 26 rotates together with the rotating shaft 22. Each of the plurality of steel plates 28 fixed to the commutator 26 includes a hook 29. A hook 29 is provided at the end nearer to the arm 23 out of the two ends in the axis A1 direction of the steel plate 28. A coil 23 </ b> B of an amateur 23 is hung on each hook 29.

  The main body 27 has a shaft hole 30 in which the rotation shaft 22 is disposed, and includes a first inner peripheral surface 31 to a third inner peripheral surface 33 that form the shaft hole 30. The second inner peripheral surface 32 is disposed between the first inner peripheral surface 31 and the third inner peripheral surface 33 in the direction along the axis A1. The inner diameter of the second inner peripheral surface 32 is larger than the inner diameter of the first inner peripheral surface 31 and larger than the inner diameter of the third inner peripheral surface 33. The first inner peripheral surface 31 is disposed between the bearing 25 and the second inner peripheral surface 32 in a direction along the axis A1. The third inner peripheral surface 33 is disposed between the second inner peripheral surface 32 and the armature 23 in the direction along the axis A1. The first inner peripheral surface 31 to the third inner peripheral surface 33 are centered on the axis A1 and are parallel to the axis A1.

  An annular first end surface 34 that connects the first inner peripheral surface 31 and the second inner peripheral surface 32 is formed. Further, an annular second end surface 35 connected to the second inner peripheral surface 32 is formed. The first end surface 34 and the second end surface 35 are perpendicular to the axis A1. An annular tapered surface 36 that connects the outer peripheral end of the second end surface 35 and the third inner peripheral surface 33 is formed. The tapered surface 36 is inclined in such a direction that the inner diameter becomes larger as it approaches the third inner peripheral surface 33 from the second inner peripheral surface 32. The arrangement range of the third inner peripheral surface 33 in the direction along the axis A1 overlaps with the arrangement range of the hook 29 in the direction along the axis A1.

  In the rotating shaft 22, the outer diameter of the portion where the commutator 26 is attached is constant, and an elastic member 37 is interposed between the outer peripheral surface of the rotating shaft 22 and the inner peripheral surface of the commutator 26. The elastic member 37 is integrally formed of an elastomer such as synthetic rubber. The elastic member 37 includes an annular boss portion 38 and a cylindrical portion 39 continuous with the boss portion 38. The boss portion 38 is arranged in a range in which the third inner peripheral surface 33 and the tapered surface 36 are formed in the direction along the axis A1. The cylinder part 39 is arrange | positioned in the range in which the 2nd inner peripheral surface 32 was formed in the direction along axis A1.

  A shaft hole 40 is provided from the boss portion 38 to the tube portion 39, and a plurality of annular recesses 41 and annular projections 42 are arranged on the inner peripheral surface of the shaft hole 40. The concave portions 41 and the convex portions 42 are alternately arranged in the direction along the axis A1. The inner diameter of the concave portion 41 is larger than the inner diameter of the convex portion 42. That is, the convex part 42 protrudes inward with respect to the concave part 41. A plurality of annular recesses 43 and annular projections 44 are arranged on the outer peripheral surface of the cylindrical portion 39. The concave portions 43 and the convex portions 44 are alternately arranged in the direction along the axis A1. The outer diameter of the concave portion 43 is smaller than the inner diameter of the convex portion 44. That is, the convex portion 44 projects outward with respect to the concave portion 43.

  The convex portion 42 and the convex portion 44 are arranged in the same range in the direction along the axis A1, and the concave portion 41 and the concave portion 43 are arranged in the same range in the direction along the axis A1. Thus, the cylinder part 39 is a bellows shape. The inner peripheral end of the convex portion 42 is in contact with the outer peripheral surface of the rotating shaft 22, and the outer peripheral end of the convex portion 44 is in contact with the second inner peripheral surface 32. The elastic member 37 is elastically deformed by receiving a radial load while being interposed between the rotating shaft 22 and the commutator 26. That is, the rotation shaft 22 is fitted in the shaft hole 40 of the elastic member 37, and the elastic member 37 is fixed to the rotation shaft 22 in the direction of the axis A <b> 1.

  Further, the outer diameter of the boss portion 38 is larger than the outer diameter of the cylindrical portion 39, and a tapered surface 45 and an annular surface 46 are formed on the outer periphery of the boss portion 38. The thickness of the boss portion 38 in the radial direction is larger than the thickness of the cylindrical portion 39 in the radial direction. Further, the tapered surface 45 is disposed between the annular surface 46 and the cylindrical portion 39 in a direction along the axis A1. As the tapered surface 45 approaches the annular surface 46, the tapered surface 45 is inclined in a direction in which the outer diameter increases. The outer diameter of the annular surface 46 is constant in the direction along the axis A1. The tapered surface 45 is in close contact with the tapered surface 36, and the annular surface 46 is in close contact with the third inner peripheral surface 33.

  Further, the first inner peripheral surface 31 of the main body 27 is in surface contact with the outer peripheral surface of the rotating shaft 22. The length L1 at which the elastic member 37 contacts the outer peripheral surface of the rotating shaft 22 in the direction along the axis A1 is such that the first inner peripheral surface 31 contacts the outer peripheral surface of the rotating shaft 22 in the direction along the axis A1. It exceeds the length L2. Furthermore, the total length of the elastic member 37 is ½ or more of the total length of the main body 27 in the direction along the axis A1. The total length of the elastic member 37 is the same as the length L1. Either the method of fixing the elastic member 37 to the main body 27, the method of fitting the boss portion 38 into the third inner peripheral surface 33, or the method of fixing the boss portion 38 and the third inner peripheral surface 33 with an adhesive. But you can.

  Next, the configuration of the casing 14 will be described. The casing 14 is made of a conductive metal material such as an aluminum alloy. Note that the casing 14 may be integrally formed of a conductive resin. The casing 14 is connected to a vehicle body as a ground by an electric wire (not shown). The casing 14 accommodates the entire speed reduction mechanism 13 and a part of the rotating shaft 22. The casing 14 includes a bottom portion 47, a side wall 48 provided along the outer periphery of the bottom portion 47, and a holding portion 49 continuous to the bottom portion 47 and the side wall 48. The holding portion 49 has a cylindrical shape, and the accommodation chamber 50 is formed by the bottom portion 47 and the side wall 48. The yoke 18 is fixed to the holding portion 49. The speed reduction mechanism 13 is disposed in the storage chamber 50. A plurality of female screw holes 65 are provided in the side wall 48, and the bracket 66 is fixed to the casing 14 using a screw member. The bracket 66 is made of metal and is fixed to the vehicle body using a screw member.

  Further, the pivot shaft 11 is rotatably supported by a support cylinder 47 </ b> A continuous with the bottom portion 47, and the pivot shaft 11 is disposed over the inside and outside of the casing 14. A brush holder 51 is provided in the holding portion 49. The brush holder 51 is attached to the holding portion 49 so as not to rotate about the axis A1. The brush holder 51 is formed in an annular shape surrounding the rotation shaft 22 and holds a plurality of, for example, two carbon brushes 52. The two brushes 52 are arranged at intervals in the rotation direction of the rotary shaft 22. The brush holder 51 is provided with a metal spring 53, and the two brushes 52 are pressed against the commutator 26 by the force of the spring 53.

  Further, a support wall 54 is provided between the holding portion 49 and the accommodation chamber 50 in the casing 14, and the bearing 25 is supported by the support wall 54. The bearing 25 and the bearing 21 are disposed concentrically, and the rotating shaft 22 is rotatably supported by the bearings 21 and 25. Further, a stopper 55 is attached to the support wall 54. The stopper 55 is a metal leaf spring. The bearing 25 is sandwiched between the stopper 55 and the support wall 54, and the rotary shaft 22 is positioned and fixed in the direction along the axis A1.

  Next, the configuration of the speed reduction mechanism 13 will be described. The accommodation chamber 50 is provided with a worm wheel 56 that can rotate around a support shaft 58. A gear 57 is provided on the outer peripheral surface of the worm wheel 56. The gear 57 meshes with the worm 24. The speed reduction mechanism 13 includes a gear 57 and a worm 24. The speed reduction mechanism 13 is a speed reduction mechanism in which the rotation speed of the worm wheel 56 is lower than the rotation speed of the rotation shaft 22 when the torque of the rotation shaft 22 is transmitted to the worm wheel 56.

  Next, the configuration of the power transmission path between the worm wheel 56 and the pivot shaft 11 will be described. A link 59 is fixed to the end of the pivot shaft 11. The pivot shaft 11 and the link 59 can operate integrally within a predetermined angle range. The connecting rod 60 is connected to the link 59 so as to be relatively rotatable. A pin 61 is provided at a position eccentric from the support shaft 58 of the worm wheel 56, and the connecting rod 60 is rotatably connected to the pin 61. The worm wheel 56, the connecting rod 60, and the link 59 are power transmission mechanisms that convert the rotational force of the rotary shaft 22 into the rotational force of the pivot shaft 11.

  A terminal holder 62 is provided between the support wall 54 and the holding portion 49 in the casing 14. A terminal 63 connected to the brush 52 is attached to the terminal holder 62. The terminal 63 is connected to a power source (not shown). Further, the terminal holder 62 is provided with a shaft hole, and the rotating shaft 22 is rotatable in the shaft hole.

  The current of the power source is supplied to the armature 23 through the terminal 63, the brush 52, and the commutator 26, and a rotating magnetic field is formed to rotate the rotor assembly 16. The rotation direction of the rotor assembly 16 is controlled to be one direction, and the rotor assembly 16 does not rotate in the reverse direction. When the rotor assembly 16 rotates, the rotational force of the rotary shaft 22 is transmitted to the worm wheel 56, and the power of the worm wheel 56 is transmitted to the pivot shaft 11 through the connecting rod 60 and the link 59. The pivot shaft 11 swings within a predetermined angle range, and the wiper member 64 wipes the windshield.

  The brush 52 is pressed against the outer peripheral surface of the commutator 26 by the force of the spring 53, and sequentially repeats contact and separation with respect to the plurality of steel plates 28 arranged in the rotation direction. Since there is a gap between the steel plates 28, the brush 52 vibrates in the radial direction of the rotating shaft 22 when the brush 52 moves from the outer peripheral surface of the predetermined steel plate 28 to the outer peripheral surface of the next steel plate 28. The vibration of the brush 52 is transmitted to the commutator 26.

  In the electric motor 12 of this embodiment, an elastic member 37 formed of synthetic rubber or elastomer is interposed between the commutator 26 and the rotating shaft 22. Vibration in the radial direction of the commutator 26 is reduced by elastic deformation of the elastic member 37, and transmission of vibration to the rotating shaft 22 can be suppressed. Therefore, resonance of the rotating shaft 22 can be suppressed and noise can be reduced. Further, since the first inner peripheral surface 31 of the main body 27 is in close contact with the outer peripheral surface of the rotating shaft 22, the commutator 26 can be fixed to the rotating shaft 22 by a fixing method similar to the conventional one.

  Further, the thickness of the boss portion 38 in the radial direction exceeds the thickness of the cylindrical portion 39 in the radial direction. Therefore, in the elastic member 37, the vibration suppressing function of the boss portion 38 is higher than the vibration suppressing function of the cylindrical portion 39. And the range in which the hook 29 is arrange | positioned and the range in which the boss | hub part 38 is arrange | positioned have overlapped in the direction along axis A1. For this reason, when the commutator 26 vibrates, it can suppress that the hook 29 vibrates.

  Another example of the elastic member 37 will be described with reference to FIG. As for the elastic member 37 shown to FIG. 5 (A), the recessed part 41A and the convex part 42A are alternately arrange | positioned at the internal peripheral surface of the axial hole 40. FIG. The concave portion 41A and the convex portion 42A are formed with a narrow width over the entire length of the elastic member 37 in the direction along the axis A1. The inner diameter of the convex portion 42A is smaller than the outer diameter of the concave portion 41A. The concave portion 41A and the convex portion 42A are inclined in the same direction in the circumferential direction.

  Further, the concave portions 43 </ b> A and the convex portions 44 </ b> A are alternately arranged on the outer peripheral surface of the cylindrical portion 39. The concave portion 43A and the convex portion 44A have a length that reaches from the portion closest to the boss portion 38 to the portion farthest from the boss portion 38 in the direction along the axis A1, and is formed narrow. . The concave portion 43A and the convex portion 44A are inclined in the same direction in the circumferential direction. The outer diameter of the concave portion 43A is smaller than the inner diameter of the convex portion 44A.

  The other structure of the elastic member 37 shown in FIG. 5A is the same as the structure of the elastic member 37 shown in FIG. When the elastic member 37 shown in FIG. 5A is used for the commutator 26 shown in FIGS. 1, 3, and 4, the same effect as the elastic member 37 shown in FIG. 4 can be obtained.

  In the elastic member 37 shown in FIG. 5B, the concave portions 41 </ b> A and the convex portions 42 </ b> A are alternately arranged on the inner peripheral surface of the shaft hole 40. The concave portion 41 </ b> A and the convex portion 42 </ b> A are formed with a narrow width over the entire length of the elastic member 37. The inner diameter of the convex portion 42A is smaller than the outer diameter of the concave portion 41A. The concave portion 41A and the convex portion 42A are inclined in the same direction in the circumferential direction. A plurality of convex portions 44 </ b> B are formed on the outer peripheral surface of the cylindrical portion 39. The plurality of convex portions 44 </ b> B have a length that reaches from a location closest to the boss portion 38 to a location farthest from the boss portion 38 in the direction along the axis A <b> 1 and is formed narrow. The plurality of convex portions 44B are inclined in the same direction in the circumferential direction.

  Further, a plurality of convex portions 44 </ b> C are formed on the outer peripheral surface of the cylindrical portion 39. The plurality of convex portions 44 </ b> C have a length that reaches from a location closest to the boss portion 38 to a location farthest from the boss portion 38 in the direction along the axis A <b> 1 and is formed narrow. The plurality of convex portions 44C are inclined in the same direction in the circumferential direction. The direction in which the plurality of protrusions 44B is inclined is opposite to the direction in which the plurality of protrusions 44C is inclined, and the plurality of protrusions 44B and the plurality of protrusions 44C intersect each other.

  And the recessed part 43B is formed between the some convex part 44B and the some convex part 44C, respectively. The other configuration of the elastic member 37 shown in FIG. 5B is the same as the configuration of the elastic member 37 shown in FIG. When the elastic member 37 shown in FIG. 5B is used in the commutator 26 shown in FIGS. 1, 3, and 4, the same effect as the elastic member 37 shown in FIG. 4 can be obtained.

  Here, the correspondence between the configuration described in the present embodiment and the configuration of the present invention will be described. The rotating shaft 22 corresponds to the rotating shaft of the present invention, the commutator 26 corresponds to the commutator of the present invention, The brush 52 corresponds to the brush of the present invention, the electric motor 12 corresponds to the electric motor of the present invention, the elastic member 37 corresponds to the elastic member of the present invention, and the recesses 43, 43A, 43B correspond to the present invention. The convex portions 44, 44A, 44B, 44C correspond to the outer convex portions of the present invention, the concave portions 41, 41A correspond to the inner concave portions of the present invention, and the convex portions 42, 42A, Corresponding to the inner convex portion of the present invention, the hook 29 corresponds to the hook of the present invention, the boss portion 38 corresponds to the boss portion of the present invention, the tube portion 39 corresponds to the tube portion of the present invention, The wiper member 64 corresponds to the wiper member of the present invention. The inner recess and the outer recess in the present invention include a groove, a notch, and the like.

  Moreover, it goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, the wiper device may be either a front wiper device that wipes the front windshield or a rear wiper device that wipes the rear windshield. The electric motor of the present invention can be used as a power source for operating the operating member. For example, the electric motor of the present invention can also be used for a power window device. The power window device is a mechanism that converts the rotational movement of an electric motor provided inside the door into a vertical movement of the door glass as an operation member, that is, a linear movement.

  The electric motor of the present invention can also be used as a power source for a power slide door device. This power slide door device is a mechanism that converts the rotational movement of an electric motor attached to the door into a door opening / closing operation as an operation member, that is, a linear movement. Furthermore, in the electric motor of the present invention, the operation of the operating member to which the power of the electric motor is transmitted may be any of rotational motion, swing motion, linear motion, and reciprocating motion.

DESCRIPTION OF SYMBOLS 10 Wiper apparatus 11 Pivot shaft 12 Electric motor 13 Deceleration mechanism 14 Casing 15 Stator assembly 16 Rotor assembly 18 Yoke 19 Permanent magnet 20 Support cylinder 21, 25 Bearing 22 Rotating shaft 23 Amateur 23A Amateur core 23B Coil 24 Worm 26 Commutator 27 Main body 28 Steel plate 29 Hook 30, 40 Shaft hole 31 First inner peripheral surface 32 Second inner peripheral surface 33 Third inner peripheral surface 34 First end surface 35 Second end surface 36 Tapered surface 37 Elastic member 38 Boss portion 39 Tube portions 41, 41A, 43 , 43A, 43B Concave portion 42, 42A, 44, 44A, 44B, 44C Convex portion 45 Tapered surface 46 Annular surface 47 Bottom portion 47A Supporting cylinder 48 Side wall 49 Holding portion 50 Storage chamber 51 Brush holder 52 Brush 53 Spring 54 Worm wheel 57 gear 58 Lifting shaft 59 link 60 connecting rod 61-pin 62 pin holder 63 terminal 64 wiper member 64A wiper arm 65 internally threaded hole 66 bracket A1 axis

Claims (6)

An electric motor comprising a cylindrical commutator attached to an outer peripheral surface of a rotating shaft, and a brush that contacts the commutator and supplies current to the commutator,
A cylindrical elastic member disposed between the rotating shaft and the commutator;
An outer concave portion and an outer convex portion formed on the outer peripheral surface of the elastic member;
An inner concave portion and an inner convex portion formed on the inner peripheral surface of the elastic member;
Having an electric motor. The electric motor according to claim 1,
The outer concave portion and the outer convex portion are annularly provided along the circumferential direction of the elastic member, and are alternately arranged in the axial direction of the rotating shaft,
The inner concave portion and the inner convex portion are provided in an annular shape along a circumferential direction of the elastic member, and are arranged alternately in the axial direction of the rotating shaft. The electric motor according to claim 2,
The outer concave portion and the outer convex portion are inclined with respect to the circumferential direction of the elastic member, and are alternately arranged in the circumferential direction of the elastic member,
The inner concave portion and the inner convex portion are inclined with respect to the circumferential direction of the elastic member and are alternately arranged in the circumferential direction of the elastic member. The electric motor according to any one of claims 1 to 3,
An armature that forms a rotating magnetic field when current is supplied from a coil is provided in a range different from the commutator in the axial direction of the rotating shaft,
A hook for supporting the coil is provided at an end of the commutator in the axial direction;
The elastic member is
A boss portion disposed in a range overlapping with a range in which the hook is disposed in the axial direction;
A cylindrical portion arranged in a range different from the boss portion in the axial direction;
With
The electric motor in which the thickness of the boss portion in the radial direction of the rotating shaft exceeds the thickness of the cylindrical portion in the radial direction. In the electric motor according to any one of claims 1 to 4,
The said elastic member is an electric motor which contacts the outer peripheral surface of the said rotating shaft in the range of 1/2 or more of the full length of the said commutator in the axial direction of the said rotating shaft. A wiper device comprising a wiper member that wipes a windshield of a vehicle, and an electric motor that operates the wiper member,
The said electric motor is a wiper apparatus as described in any one of Claims 1-5.

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