JP6208841B2 - Brush device and motor - Google Patents

Description

  The present invention relates to a brush device for bringing a brush into contact with a commutator and a motor including the brush device.

  Conventionally, a motor includes a power supply brush whose tip is in contact with the outer peripheral surface of a commutator that is externally fitted and fixed to a rotary shaft that is rotationally driven, a cylindrical brush holder that holds the brush inside, Some have a brush device having a spring that biases the rear end of the brush toward the commutator. Such brush devices include one using a torsion spring as a spring for urging the rear end of the brush. When the torsion spring is used, the brush device can be reduced in size as compared with the case where a coil spring is used, for example. However, in general, the torsion spring presses the rear end surface of the brush at one point and biases the brush toward the commutator. Furthermore, the inner peripheral surface of the brush holder is formed to be slightly larger than the outer shape of the brush in consideration of the thermal expansion of the brush. For this reason, when the rotary shaft is driven to rotate, that is, when the commutator is rotated, the brush posture is difficult to stabilize inside the brush holder, and the contact state between the brush tip and the commutator becomes unstable. It was.

  Therefore, in the brush device described in Patent Document 1, in order to bring the brush into contact with the commutator in a stable state, a plate-like pressing member provided at the rear end of the brush is urged by a torsion spring, and the pressing The urging force of the torsion spring is transmitted to the brush through the member.

JP 2010-124518 A

  However, in the brush device described in Patent Document 1, since the torsion spring presses the pressing member at one point, it is difficult to stabilize the urging direction of the pressing member by the torsion spring. For this reason, the direction in which the brush is urged via the pressing member is difficult to stabilize, and there is a risk that the brush will rattle (explode) inside the brush holder. In addition, since a pressing member is added, the number of parts is increased.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a brush device and a motor capable of suppressing brush play without increasing the number of components.

  A brush device that solves the above problem is provided in a cylindrical cover portion that accommodates a commutator, and has a pair of inner side surfaces that are spaced apart in the axial direction of the commutator and extends in a substantially radial direction of the commutator. A brush housed in a state having a gap in the brush holder and having a tip that contacts the commutator, and a torsion spring that urges the rear end of the brush toward the commutator The torsion spring biases the brush toward the commutator by pressing a position shifted from the center line of the brush in the axial direction of the commutator at a rear end portion of the brush. The brush is urged by the torsion spring to contact one inner surface of the pair of inner surfaces at the tip side and the other inner surface at the rear end side. The inner side surface, which is configured to contact, and contacts the tip side of the brush among the pair of inner side surfaces, is seen from the commutator side end of the inner side surface as viewed from the axial direction of the commutator, It has a linear part that forms a straight line perpendicular to the axial direction of the commutator and perpendicular to the direction in which the brush holder extends, and the brush is configured to contact the linear part on its tip side, An end portion on the radially inner side of the brush holder protrudes on the inner side of the cover portion, and an inner opening portion that opens on the inner side of the cover portion is formed on the end portion on the radially inner side of the brush holder. The straight portion constitutes a part of the inner opening.

  A motor that solves the above-described problems includes the commutator that is fixed to a rotary shaft that is rotationally driven so as to be integrally rotatable, and the brush device that includes the brush that is in sliding contact with an outer peripheral surface of the commutator.

  ADVANTAGE OF THE INVENTION According to this invention, the brush apparatus and motor which can suppress the shakiness of a brush, without increasing a number of parts can be provided.

The front view of a motor. The perspective view of the motor part in 1st Embodiment. The end view of the motor part in 1st Embodiment (CC end view in FIG. 4). The end view of the motor part in a 1st embodiment (the AA end view and BB end view in Drawing 3). The enlarged view near the front-end | tip part of the brush in the motor part of 1st Embodiment. The enlarged view near the rear-end part of the brush in the motor part of 1st Embodiment. The schematic diagram of the brush apparatus in 1st Embodiment. The perspective view of the base member of 2nd Embodiment. The top view of the base member of 2nd Embodiment. The enlarged view near the front-end | tip part of the brush in the motor part of 2nd Embodiment. The schematic diagram of the brush apparatus of another form. The schematic diagram of the brush apparatus of another form. The schematic diagram of the brush apparatus of another form.

(First embodiment)
A first embodiment of the present invention will be described below with reference to the drawings.
A motor 1 according to this embodiment shown in FIG. 1 is used as a drive source of a power window device that lifts and lowers a window glass of a vehicle electrically. The motor 1 includes a motor unit 2 located in the upper part in FIG. 1, a speed reduction part 3 provided on the output side of the motor part 2 (below the motor part 2 in FIG. 1), and a side of the speed reduction part 3 (see FIG. 1 on the left side in FIG.

  A yoke housing 11 (hereinafter simply referred to as a yoke 11) of the motor unit 2 has a cylindrical shape in which one end (the upper end in FIG. 1) is closed. Further, a flange portion 11 a extending radially outward is formed in the opening at the other end of the yoke 11. A magnet (not shown) is fixed to the inner peripheral surface of the yoke 11, and an armature 12 is disposed inside the magnet.

  The armature 12 includes a columnar rotary shaft 13 disposed in the central portion of the yoke 11 in the radial direction, an armature core 14 fixed to the rotary shaft 13 so as to be integrally rotatable, and the armature core 14 is wound around the armature core 14. The coil 15 is mounted, and the commutator 16 is fixed to the distal end side (lower end side in FIG. 1) of the rotating shaft 13 with respect to the armature core 14.

  A base end portion (upper end portion in FIG. 1) of the rotating shaft 13 is pivotally supported by a bearing (not shown) provided at the bottom center of the yoke 11. Further, the tip end portion (the lower end portion in FIG. 1) of the rotating shaft 13 protrudes from the opening portion of the yoke 11 to the outside of the yoke 11. The armature core 14 is fixed to a portion of the rotating shaft 13 disposed inside the yoke 11 and faces the magnet (not shown) in the radial direction. On the other hand, the commutator 16 is externally fitted and fixed to a portion of the rotating shaft 13 that protrudes to the outside of the yoke 11 so as to rotate integrally with the rotating shaft 13.

  The commutator 16 has a cylindrical shape, and a plurality of segments 16a are arranged in parallel on the outer peripheral surface thereof so as to be separated in the circumferential direction. Some or all of the segments 16a are electrically connected to the coil 15. That is, power can be supplied to the coil 15 via the segment 16 a of the commutator 16.

  As shown in FIGS. 1 and 2, a brush holder assembly 21 is disposed in the opening of the yoke 11 so as to substantially close the opening. The brush holder assembly 21 constituting the motor unit 2 is formed by mounting an electronic component or the like on a base member 22 disposed in the opening of the yoke 11.

  The base member 22 is formed of an insulating resin material. The base member 22 has a substantially flat base 23 that closes the opening of the yoke 11, and the outer shape of the base 23 is slightly larger than the opening of the yoke 11. In addition, a seal member 24 is provided at the outer edge of the base portion 23 to ensure liquid-tightness between a gear housing 41 and a yoke 11 of the speed reduction unit 3 described later. The seal member 24 is formed of, for example, an elastomer.

  As shown in FIGS. 2 and 3, a bottomed cylindrical cover portion 25 that opens toward the yoke 11 is formed integrally with the base portion 23 at the center portion of the base portion 23. The cover portion 25 protrudes from the base portion 23 along the axial direction in the opposite direction to the yoke 11, and a bearing 26 is held at the bottom center of the cover portion 25. A portion on the tip side of the rotary shaft 13 protruding from the opening of the yoke 11 passes through the center portion in the radial direction of the cover portion 25 and penetrates the bottom portion of the cover portion 25, and is supported by the bearing 26. . That is, the rotary shaft 13 is supported by the bearing 26 and a bearing (not shown) provided at the center of the bottom of the yoke 11 so that the rotary shaft 13 can rotate about the central axis L1 of the rotary shaft 13. It has become. The commutator 16 is accommodated in the cover portion 25.

  In addition, brush devices 31 are provided at two locations on the end surface in the axial direction on the side opposite to the yoke 11 in the base portion 23 and on the radially outer side of the cover portion 25. The two brush devices 31 each have a brush holder 32, a brush 33 held in the brush holder 32, and a torsion spring 34 that urges the rear end portion of the brush 33 toward the commutator 16.

  The brush holders 32 of the two brush devices 31 are formed at two locations 90.degree. Apart from each other in the circumferential direction of the cover portion 25 (the same as the circumferential direction of the commutator 16) outside the cover portion 25 in the radial direction. 23 is formed integrally. Each brush holder 32 has a substantially square cylindrical shape extending in a substantially radial direction of the cover portion 25 (same as the substantially radial direction of the commutator 16). As shown in FIGS. 3 and 4, the radially inner end of the brush holder 32 is formed integrally with the cover portion 25, and the internal space of the brush holder 32 has an insertion opening formed in the cover portion 25. It communicates with the internal space of the cover part 25 via 25a. 4, the outer side of the one-dot chain line circle passing through the cover portion 25 is an AA end view in FIG. 3, and the inner side of the one-dot chain line circle passing through the cover portion 25 is a BB end view in FIG. 3. It has become.

  As shown in FIGS. 2 and 3, the pair of side walls 32a and 32b spaced apart in the axial direction (the axial direction of the commutator 16) in the brush holder 32 form a flat plate shape, and the end portions on the radially inner side cover the cover. It is formed integrally with the part 25. Further, the pair of side walls 32 a and 32 b are inclined toward one end in the axial direction of the commutator 16 from the radially outer end toward the radially inner end. Note that the axial direction of the commutator 16 is the same as the direction of the central axis L <b> 1 of the rotating shaft 13. In the present embodiment, the side walls 32a and 32b have an axis line on the opening side (the yoke 11 side) of the cover portion 25 in the commutator 16 from the radially outer end portion toward the radially inner end portion. Inclined towards the end of the direction. Therefore, the axial distance between the side walls 32a and 32b and the base portion 23 is shortened from the radially outer end toward the radially inner end. The pair of side walls 32a and 32b are parallel to each other. Of the pair of side walls 32a and 32b, the first inner side surface S1, which is the inner side surface of the side wall 32a on the bottom side of the cover portion 25, is directed from the radially outer end to the radially inner end. Accordingly, the commutator 16 is inclined toward the one end side in the axial direction of the commutator 16. Similarly, the second inner side surface S2 which is the inner side surface of the side wall 32b opposite to the bottom of the cover portion 25 (that is, the opening side of the cover portion 25) of the pair of side walls 32a and 32b is As it goes from the end toward the radially inner end, it is inclined toward the commutator 16 toward one end in the axial direction of the commutator 16. In the present embodiment, the first inner side surface S1 and the second inner side surface S2 are end portions in the axial direction on the opening side (the yoke 11 side) of the cover portion 25 of the commutator 16 toward the commutator 16. It is inclined towards. The first inner side surface S1 and the second inner side surface S2 are spaced apart in the axial direction of the commutator 16 and each have a planar shape.

  As shown in FIGS. 2 and 4, the pair of side walls 32c and 32d spaced apart in the circumferential direction (the circumferential direction of the commutator 16) in the brush holder 32 are provided on both sides of the pair of side walls 32a and 32b in the circumferential direction. It is formed integrally with the pair of side walls 32a and 32b. The pair of side walls 32c and 32d form a flat plate standing in the axial direction and are parallel to each other. Further, the axial end portions of the side walls 32c and 32d on the base 23 side are integrally formed with the base portion 23, and the radially inner ends of the side walls 32c and 32d are integrally formed with the cover portion 25. Yes.

  In the brush holder 32, the side wall 32a is formed with an insertion groove 32e extending radially inward from the radially outer end. The insertion groove 32e penetrates the side wall 32a in the axial direction (axial direction of the commutator 16) and opens on both sides in the axial direction, and opens only radially outward in the radial direction.

  As shown in FIGS. 3 and 4, the brush 33 inserted into the brush holder 32 as described above has a quadrangular prism shape. The outer shape of the brush 33 is formed slightly smaller than the inner peripheral surface of the square cylindrical shape of the brush holder 32. Therefore, the brush 33 is accommodated in the brush holder 32 with a gap. Thus, even if the brush 33 is thermally expanded when the motor unit 2 is driven by accommodating the brush 33 with a gap in the brush holder 32, the brush 33 is commutated inside the brush holder 32. 16 can be moved in the radial direction. Further, the tip of the brush 33 enters the inside of the cover portion 25 through the insertion opening 25 a and can contact the outer peripheral surface of the commutator 16. Further, the brush 33 is disposed between the first and second inner side surfaces S1, S2 inclined toward one end side in the axial direction of the commutator 16 toward the commutator 16, so that the brush 33 moves from the rear end toward the front end. The commutator 16 is inclined with respect to the diameter direction of the commutator 16 so as to approach one end in the axial direction of the commutator 16 (an end portion of the commutator 16 on the yoke 11 side in the axial direction). In addition, the first side surface 33a that faces the first inner side surface S1 in the brush 33 in the axial direction and the second side surface 33b that faces the second inner side surface S2 in the brush 33 in the axial direction are parallel to each other. It is flat.

  As shown in FIG. 3, the tip of the brush 33 is formed such that the axial width gradually decreases toward the tip of the brush 33 (commutator 16 side), and the tip is triangular. Pointed. Thus, the state where the tip of the brush 33 is pointed in a triangular shape is a state before the running-in operation of the motor 1 (that is, a state before the brush 33 is worn). A pair of inclined surfaces 33 d and 33 e are formed at the tip of the brush 33 so that the distance between them in the axial direction becomes narrower toward the tip of the brush 33. Further, as shown in FIG. 5, when viewed from the axial direction of the commutator 16, the tip of the brush 33 is recessed so as to form an arc shape substantially along the outer peripheral surface of the commutator 16. Further, when viewed from the axial direction of the commutator 16, the tip of the brush 33 has an arc shape that is line symmetric with respect to the center line L <b> 2 of the brush 33. The center line L2 of the brush 33 is a straight line extending from the front end to the rear end of the brush 33 and passing through the center of the brush 33. Further, the radius of curvature of the tip of the brush 33 that is recessed in an arc shape is larger than the radius of curvature of the outer peripheral surface of the commutator 16. Therefore, the tip of the brush 33 contacts the outer peripheral surface of the commutator 16 at the center in the circumferential direction. In the present embodiment, the tip of the brush 33 is in point contact with the outer peripheral surface of the commutator 16 at the center in the circumferential direction or in a state where the contact area is small and close to point contact (including line contact). Further, when the tip of the brush 33 held by the brush holder 32 is in contact with the outer peripheral surface of the commutator 16, a gap is formed between the inclined surfaces 33 d and 33 e and the outer peripheral surface of the commutator 16. Yes.

  As shown in FIG. 3, at the end of the brush 33 at the one end side in the axial direction of the commutator 16 (in this embodiment, one end side in the axial direction on the opening side of the cover portion 25 in the commutator 16). Is formed with a step recess 33f that is recessed to form a step in the direction of the center line L2 of the brush 33. Of the inner surface of the stepped recess 33f, the center of the pressing surface 33g that faces the direction opposite to the tip of the brush 33 and is orthogonal to the center line L2 of the brush 33 is opposite to the tip of the brush 33. A follow-up recess 33h is formed in the opening. As shown in FIGS. 4 and 6, the tracking recess 33h is a straight line passing through the contact point P1 of the brush 33 with the commutator 16 on the pressing surface 33g and parallel to the center line L2 when viewed from the axial direction of the commutator 16. It is formed in a region including L3. In the present embodiment, the contact point P1 is located at the center of the tip of the brush 33 in the circumferential direction. Therefore, when the brush 33 is viewed from the axial direction of the commutator 16, the straight line L3 coincides with the center line L2. The follow-up recess 33h is recessed so that the width in the direction along the circumferential direction of the commutator 16 gradually decreases from the opening toward the bottom. In this embodiment, the cross-sectional shape obtained by cutting the follow-up concave portion 33h by a plane orthogonal to the axial direction of the commutator 16 forms a substantially V-shape that opens in the opposite direction to the tip of the brush 33, and the center line L2 It has a symmetric shape with the (straight line L3) as the axis of symmetry.

  As shown in FIGS. 2 and 4, the torsion spring 34 includes a coil portion 34a, a locking portion 34b protruding from one end of the coil portion 34a, and a pressing portion 34c protruding from the other end of the coil portion 34a. . Support columns 27 are formed in the vicinity of the brush holders 32 on the axial end surface of the base 23 opposite to the yoke 11. The support column 27 extends in the axial direction and has a cylindrical shape having an outer diameter substantially equal to the inner diameter of the coil portion 34a. A coil portion 34 a of a torsion spring 34 is extrapolated to each column 27. The central axis L4 of the coil portion 34a extrapolated to the support column 27 is substantially parallel to the axial direction of the commutator 16. In each brush device 31, the locking portion 34 b of the torsion spring 34 is inserted and locked in a locking groove 25 b formed between the two support columns 27 on the outer peripheral surface of the cover portion 25.

  Further, in each brush device 31, the front end portion of the pressing portion 34 c of the torsion spring 34 is in contact with the rear end portion of the brush 33 and urges the brush 33 toward the commutator 16. An insertion groove (not shown) that extends in the radial direction of the commutator 16 and allows the pressing portion 34c to move toward the commutator 16 is formed in the side wall 32c of the brush holder 32. The pressing portion 34c is formed of the insertion groove. It passes through and contacts the rear end of the brush 33.

  As shown in FIGS. 4 and 6, a pressing convex portion 34 d that protrudes toward the rear end portion of the brush 33 is formed at the tip end portion of the pressing portion 34 c (that is, one end portion of the torsion spring). The pressing protrusion 34 d protrudes in an arc shape when viewed from the axial direction of the commutator 16. Furthermore, the circumferential width of the commutator 16 in the pressing convex portion 34d is formed wider than the circumferential width of the commutator 16 in the follow-up concave portion 33h.

  In each brush device 31, the pressing convex portion 34 d of the torsion spring 34 has the tip end portion of the pressing convex portion 34 d inserted into the tracking recess 33 h and the inner peripheral surface of the tracking recess 33 h toward the commutator 16. Pressing. The torsion spring 34 urges the brush 33 toward the commutator 16 by pressing the inner peripheral surface of the tracking recess 33h with the pressing protrusion 34d. Since the central axis L4 of the coil portion 34a is substantially parallel to the axial direction of the commutator 16, the torsion spring 34 biases the brush 33 in a direction substantially parallel to the diameter direction of the commutator 16. . Further, the torsion spring 34 presses the inner peripheral surface of the tracking recess 33h with the pressing protrusion 34d, so that one end in the axial direction of the commutator 16 with respect to the center line L2 at the rear end of the brush 33 (this embodiment). Then, the position of the commutator 16 on the one end side in the axial direction on the yoke 11 side is pressed. Further, as shown in FIGS. 3 and 7, the location where the brush 33 is pressed by the torsion spring 34 and the location where the brush 33 and the commutator 16 are in contact with each other are shifted in the axial direction of the commutator 16.

  Further, as shown in FIGS. 4 and 6, the pressing convex portion 34d inserted into the tracking recess 33h presses two locations separated in the circumferential direction of the commutator 16 on the inner peripheral surface of the tracking recess 33h. Since the circumferential width of the commutator 16 in the pressing convex portion 34d is formed wider than the circumferential width of the commutator 16 in the tracking concave portion 33h, the pressing convex portion 34d has both ends in the circumferential direction of the tracking concave portion 33h. Each is pressed. The two pressing points P4 and P5 pressed by the pressing protrusion 34d on the inner peripheral surface of the tracking recess 33h are respectively located on both sides of the center line L2 (straight line L3) when viewed from the axial direction of the commutator 16. One place is provided.

  Then, as shown in FIG. 7, the urging force F <b> 1 of the torsion spring 34 and the drag F <b> 2 received from the commutator 16 along with the urging by the torsion spring 34 act on the brush 33. When the brush 33 is viewed from the circumferential direction of the commutator 16 (that is, the state shown in FIG. 7), the urging force F1 of the torsion spring 34 is along a straight line (not shown) connecting the pressing points P4, P5 and the contact point P1. The component force F1a and the component force F1b orthogonal to the component force F1a are decomposed. The drag force F2 is broken down into a component force F2a along a straight line (not shown) connecting the pressing points P4, P5 and the contact point P1, and a component force F2b orthogonal to the component force F2a. The component force F1b biases the rear end portion of the brush 33 toward the second inner surface S2, and the component force F2b biases the tip portion of the brush 33 toward the first inner surface S1. To do. Therefore, the front end and the rear end of the brush 33 are displaced in the axial direction of the commutator 16 by the component force F1b and the component force F2b generated by urging the brush 33 with the torsion spring 34. A rotational force is applied to rotate the brush 33 (in the direction of arrow α in FIG. 7). The brush 33 to which the rotational force is applied is inclined in the axial direction of the commutator 16 with respect to the brush holder 32 inside the brush holder 32, and comes into contact with the first inner surface S <b> 1 on the tip side. In addition to being pressed, the rear end side comes into contact with the second inner surface S2 and is pressed. In addition, the contact location which the brush 33 contacted in 1st inner surface S1 is made into the 1st contact support point P2, and the contact location which the brush 33 contacted in 2nd inner surface S2 is made into the 2nd contact support point P3. .

  As shown in FIGS. 2 and 3, one end of a pigtail 35 for supplying power to the brush 33 is connected to the rear end of the brush 33. In the present embodiment, the pigtail 35 is located at the rear end of the brush 33 on the opposite side of the center line L2 with respect to the pressing position of the brush 33 by the torsion spring 34 (that is, the pressing points P4 and P5). It is connected. Accordingly, one end of the pigtail 35 is connected to the side surface on the other end side in the axial direction of the commutator 16 in the brush 33, that is, the portion on the rear end side of the brush 33 in the first side surface 33 a. The pigtail 35 is drawn out of the brush holder 32 through the insertion groove 32e formed in the side wall 32a of the brush holder 32. The other end of each pigtail 35 connected to each brush 33 is connected to the base 23 via a choke coil 28 (only one is shown in FIG. 2). 29 are electrically connected to each other. The choke coil 28 is a noise prevention element for removing noise included in the power supplied to the armature 12.

  As shown in FIG. 1, the speed reduction unit 3 includes a gear housing 41 and a speed reduction mechanism 42 accommodated in the gear housing 41. The gear housing 41 includes a holder housing portion 43 that is fixed to the flange portion 11 a of the yoke 11, and a worm shaft housing portion 44 that extends from the holder housing portion 43 in the direction opposite to the yoke 11 along the direction of the central axis L <b> 1 of the rotary shaft 13. And a worm wheel housing portion 45 formed on the side of the worm shaft housing portion 44 (on the right side in FIG. 1).

  The gear housing 41 is fixed to the yoke 11 by fixing a holder housing portion 43 that is in contact with the flange portion 11 a in the axial direction to the flange portion 11 a with a plurality of screws 46. Inside the holder accommodating portion 43, a portion on the distal end side of the rotating shaft 13 enters and the commutator 16 is disposed. Further, inside the holder accommodating portion 43, portions such as a cover portion, a brush device 31, and the like that protrude from the opening portion of the yoke 11 in the brush holder assembly 21 to the outside of the yoke 11 are disposed.

  A substantially cylindrical worm shaft 47 is accommodated in the worm shaft accommodating portion 44. A screw-like worm portion 47 a is formed at a substantially central portion in the axial direction of the worm shaft 47. The worm shaft 47 is disposed coaxially with the rotation shaft 13 (arranged so that the center axes thereof coincide with each other), and can be rotated around the center axis L5 inside the worm shaft housing portion 44. is there. Further, the base end portion (the upper end portion in FIG. 1) of the worm shaft 47 is connected to the distal end portion of the rotating shaft 13 via a clutch 48 disposed in the holder housing portion 43. The clutch 48 operates so as to transmit the rotational driving force of the rotating shaft 13 to the worm shaft 47 while not transmitting the rotating force from the worm shaft 47 to the rotating shaft 13.

  The internal space of the worm wheel storage portion 45 is connected to the internal space of the worm shaft storage portion 44. A disc-shaped worm wheel 49 that meshes with the worm portion 47 a is accommodated in the worm wheel accommodating portion 45. The worm wheel 49 and the worm shaft 47 constitute the speed reduction mechanism 42. An output shaft 50 extending along the axial direction of the worm wheel 49 is provided at the central portion in the radial direction of the worm wheel 49 so as to be able to rotate integrally with the worm wheel 49. The front end portion of the output shaft 50 protrudes outside the gear housing 41, and the window glass of the vehicle is connected to the front end portion of the output shaft 50 via a window regulator (not shown).

  The connector portion 4 is assembled to the holder accommodating portion 43. The connector portion 4 is formed from an opening (not shown) formed in the holder housing portion 43 on the opposite side (left side in FIG. 1) to the worm wheel housing portion 45 with the central axis L1 of the rotation shaft 13 interposed therebetween. 43. As shown in FIGS. 1 and 2, the connector section 4 includes a connector housing 61 fixed to the gear housing 41, a plurality of external connection terminals 62 and a control IC 63 held inside the connector housing 61. The external connection terminal 62 is electrically connected to the control IC 63 inside the connector housing 61 and is exposed to the outside of the connector housing 61 inside a cylindrical external connection portion 61 a formed in the connector housing 61. . When the connector portion 4 is inserted into the holder housing portion 43, the control IC 63 is electrically connected to the two power supply terminals 29. Further, when an external connector (not shown) for inputting / outputting electric signals and supplying power is connected to the external connection portion 61a, the external connection terminal 62 is electrically connected to the external connector. .

Next, the operation of the motor 1 of the present embodiment provided with the brush device 31 will be described.
The power supplied from the external connector to the connector unit 4 is supplied from the control IC 63 to the brush 33 via the power supply terminal 29 and the pigtail 35. The power supplied to the brush 33 is supplied to the coil 15 via the commutator 16. As a result, the armature 12 (rotating shaft 13) is rotationally driven, and the rotational driving force of the rotating shaft 13 is transmitted to the worm shaft 47 via the clutch 48 and is decelerated by the worm portion 47a and the worm wheel 49. And output from the output shaft 50. Then, the window glass is lowered or raised through the window regulator connected to the output shaft 50 according to the rotation direction of the output shaft 50.

  Further, as shown in FIG. 7, in each brush device 31, the component force F <b> 1 b of the urging force F <b> 1 of the torsion spring 34 and the force F <b> 2 received by the brush 33 from the commutator 16 due to the urging by the torsion spring 34. Due to the action of the force F <b> 2 b, a rotational force in the direction of arrow α is applied to the brush 33 in order to rotate the brush 33 so that the front end and the rear end of the brush 33 are displaced in the axial direction of the commutator 16. The brush 33 that has received this rotational force has the first side surface 33a in contact with the first inner side surface S1 at the front end side thereof, and the second side surface 33b in contact with the second inner side surface S2 at the rear end side thereof. . The force with which the torsion spring 34 tries to rotate the brush 33 is the first contact support point P2 located on the distal end side of the brush holder 32 on the first inner side surface S1 and the second inner side surface S2. The first contact support point P2 and the second contact support point P3 located on the rear end side of the brush holder 32 are received. Accordingly, the brush 33 is displaced in the radial direction of the commutator 16 (in the direction of the center line L2) and the first contact support point P2 and the second contact point P2 that are located on both sides of the commutator 16 in the axial direction across the center line L2. It is supported by the brush holder 32 at the contact support point P3.

  The pigtail 35 is connected to a position on the opposite side of the center line L <b> 2 with respect to a location where the brush 33 is pressed by the torsion spring 34 at the rear end of the brush 33. Therefore, the force F3 acting on the rear end portion of the brush 33 from the pigtail 35 is substantially the same as the direction in which the rear end portion of the brush 33 tries to rotate by being urged by the torsion spring 34 (the arrow α direction in FIG. 7). The same direction. Accordingly, the force F3 acting on the brush 33 from the pigtail 35 also acts to push the rear end portion of the brush 33 toward the second inner surface S2.

  Further, the tip of the brush 33 has a triangular shape before the running-in operation of the motor 1 is performed. Then, when the running-in operation of the motor 1 is performed, the brush 33 starts to be worn from a pointed triangular shape at the tip of the brush 33. Then, as the tip of the brush 33 is worn, the contact area between the tip of the brush 33 and the outer peripheral surface of the commutator 16 increases. Finally, the tip of the brush 33 has a shape curved in an arc shape along the outer peripheral surface of the commutator 16 when viewed from the axial direction of the commutator 16. Further, the brush 33 has a shape in which the inclined surfaces 33d and 33e that existed before the running-in operation of the motor 1 are eliminated, that is, a shape in which a pointed portion of the triangle at the tip is eliminated. As a result, the tip portion of the brush 33 becomes the thickest quadrangular columnar portion of the brush 33, so that the entire substantially square tip surface of the quadrangular columnar portion is in sliding contact with the outer peripheral surface of the commutator 16. Therefore, the brush 33 stably contacts the commutator 16.

  As shown in FIGS. 4 and 6, when the tip of the brush 33 is worn, the rear end of the brush 33 gradually moves toward the commutator 16 (in the radial direction) (in FIG. 6, two ends). (See dotted line). At this time, with the wear of the brush 33, the pressing portion 34c of the torsion spring 34 rotates around the coil portion 34a (see the two-dot chain line in FIG. 6). Even if the pressing portion 34c rotates around the coil portion 34a with the wear of the brush 33, the pressing convex portion 34d protruding in an arc shape on the rear end side of the brush 33 has an outer peripheral surface and a tracking concave portion 33h. It is possible to maintain a state in which the inner peripheral surface of the tracking recess 33h is pressed at one location on both sides of the straight line L3 (center line L2 of the brush 33) while being in sliding contact with the inner peripheral surface.

As described above, the first embodiment has the following effects.
(1) The torsion spring 34 presses a position shifted from the center line L <b> 2 of the brush 33 in the axial direction of the commutator 16 at the rear end portion of the brush 33. Therefore, it is easy to apply a rotational force to the brush 33 to rotate the brush 33 so that the front end and the rear end of the brush 33 are displaced in the axial direction of the commutator 16. The brush 33 to which the rotational force is applied is pressed in contact with the first inner surface S1 on the tip side, and pressed in contact with the second inner surface S2 on the rear end side. Become. Accordingly, since the brush 33 is difficult to move in the axial direction of the commutator 16 inside the brush holder 32, rattling (rambling) of the brush 33 in the axial direction of the commutator 16 can be suppressed. Further, the brush 33 can be brought into contact with the commutator 16 in a stable state. Further, the back end portion of the brush 33 rattles in the brush holder 32 by pressing a position shifted in the axial direction of the commutator 16 from the center line L2 of the brush 33 by the torsion spring 34. Therefore, it is not necessary to increase the number of parts.

  (2) The first inner side surface S1 and the second inner side surface S2 are inclined toward one end side in the axial direction of the commutator 16 toward the commutator 16. The torsion spring 34 presses the position on the one end side in the axial direction of the commutator 16 with respect to the center line L <b> 2 at the rear end portion of the brush 33. Therefore, when the torsion spring 34 urges the rear end portion of the brush 33 in a direction substantially parallel to the diameter direction of the commutator 16, the front end and the rear end of the brush 33 are displaced in the axial direction of the commutator 16. It is easily rotated and can contact the first inner side surface S1 on the front end side and can contact the second inner side surface S2 on the rear end side. Accordingly, the direction in which the brush 33 is urged by the torsion spring 34 does not have to be a complicated direction such as a direction inclined with respect to the diameter direction of the commutator 16, so that the structure of the brush device 31 is complicated. It is suppressed.

  (3) The torsion spring 34 presses the position on the one end side in the axial direction of the commutator 16 with respect to the center line L <b> 2 at the rear end portion of the brush 33. The brush 33 is in contact with the commutator 16 on the other end side in the axial direction of the commutator 16 with respect to the center line L2. Therefore, it is easy to increase the rotational force for rotating the brush 33 so that the front end and the rear end of the brush 33 are displaced in the axial direction of the commutator 16, which is generated when the torsion spring 34 biases the brush 33. . Accordingly, the brush 33 can be pressed more strongly against the first inner side surface S1 at the tip end side of the brush 33, and the brush 33 can be pressed more strongly against the second inner side surface S2 at the rear end side of the brush 33. Therefore, since the brush 33 is less likely to move in the axial direction of the commutator 16 inside the brush holder 32, rattling of the brush 33 in the axial direction of the commutator 16 can be further suppressed.

  (4) Approximately the same rotational force as the brush 33 that rotates when the torsion spring 34 biases the brush 33 so that the front and rear ends of the brush 33 are displaced in the axial direction of the commutator 16. Directional force is applied from the pigtail 35 to the brush 33. Accordingly, since the brush 33 is more difficult to move in the axial direction of the commutator 16 inside the brush holder 32, rattling of the brush 33 in the axial direction of the commutator 16 can be further suppressed.

  (5) The brush 33 is in contact with the commutator 16 at one location. Then, the torsion spring 34 presses two places spaced apart in the circumferential direction of the commutator 16 at the rear end portion of the brush 33, and the pressing part of the brush 33 by the torsion spring 34 (that is, the pressing points P4 and P5) is rectified. When viewed from the axial direction of the child 16, one is provided on each side of a straight line L <b> 3 that passes through a contact portion (that is, a contact point P <b> 1) between the brush 33 and the commutator 16 and is parallel to the center line L <b> 2. Therefore, it is possible to suppress the brush 33 from rattling (running out) in the circumferential direction of the commutator 16 inside the brush holder 32.

  (6) The pressing convex portion 34 d has an arc shape protruding toward the rear end portion side of the brush 33 when viewed from the axial direction of the commutator 16. Therefore, even if the pressing portion 34c rotates with the wear of the brush 33, the pressing convex portion 34d presses two locations that are spaced apart in the circumferential direction of the commutator 16 and sandwich the straight line L3 on the inner peripheral surface of the follow-up concave portion 33h. Can be maintained. Therefore, even if the brush 33 is worn, rattling of the brush 33 in the circumferential direction of the commutator 16 can be suppressed.

  (7) Since the motor 1 includes the brush device 31 in which the brush 33 in the brush holder 32 is prevented from rattling (runaway), noise generation due to rattling of the brush 33 in the motor 1 is suppressed. Is done. Further, since the brush 33 is in contact with the commutator 16 in a stable state, excessive wear of the brush 33 is suppressed and the life of the brush 33 is suppressed from being shortened. Accordingly, it is possible to suppress the life of the motor 1 from being shortened.

(Second Embodiment)
Hereinafter, a second embodiment of the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the structure similar to the said 1st Embodiment, and the description is abbreviate | omitted.

  A base member 71 of the second embodiment shown in FIG. 8 is provided in the brush holder assembly 21 of the motor 1 in place of the base member 22 of the first embodiment. Similar to the base member 22 of the first embodiment, the base member 71 is formed of an insulating resin material, and includes a cover portion 25 and a brush holder 32 that constitutes the brush device 31.

  As shown in FIGS. 8 and 10, in the second embodiment, the brush holder 32 of the two brush devices 31 has a radially inner end protruding slightly inside the cover portion 25. An inner opening 32 h that opens to the inside of the cover portion 25 is formed at the radially inner end of each brush holder 32. The internal space of each brush holder 32 communicates with the internal space of the cover portion 25 through the inner opening 32h. The inner opening 32h has a quadrangular shape through which the brush 33 can be inserted.

  Further, as shown in FIG. 9, in the radially inner end surface of the brush holder 32 protruding to the inside of the cover portion 25 (that is, the front end surface of the brush holder 32), the peripheral portion of the inner opening portion 32 h has a planar shape. A flat surface portion 32k is formed. The planar portion 32k is parallel to the axial direction of the commutator 16 accommodated in the cover portion 25 and has a planar shape orthogonal to the extending direction of the brush holder 32. Note that the extending direction of the brush holder 32 is the radial direction of the commutator 16 as in the first embodiment, and is indicated by a one-dot chain line in FIGS. 9 and 10. Further, the axial direction of the commutator 16 is a direction perpendicular to the paper surface in FIGS.

  As shown in FIGS. 8 and 9, in each brush holder 32, the radially inner ends of the first inner surface S1 and the second inner surface S2 extend to the inner opening 32h. The first inner side surface S1 forms a straight line at the end of the first inner side surface S1 on the side of the commutator 16 that is orthogonal to the axial direction of the commutator 16 and orthogonal to the direction in which the brush holder 32 extends. A straight portion 72 is provided. Since the first inner surface S1 extends radially inward to the inner opening 32h, the linear portion 72 forms a part of the inner opening 32h. The straight portion 72 of the second embodiment is one side of the first inner surface S1 on the side of the commutator 16 and is located at a corner formed by the first inner surface S1 and the flat portion 32k. It is a straight line of books. Further, as shown in FIGS. 8 and 10, the length of the straight portion 72 (the length in the direction orthogonal to the direction in which the brush holder 32 extends when viewed from the axial direction of the commutator 16) is the width of the brush 33 (rectification). It is formed longer than the width of the child 16 as viewed from the axial direction.

  And in each brush apparatus 31, the brush 33 inserted in the brush holder 32 presses a rear-end part toward the commutator 16 by the torsion spring 34 (refer FIG.4 and FIG.7) similarly to the said 1st Embodiment. As a result, the torsion spring 34 is biased toward the commutator 16. A rotational force is applied to the brush 33 to rotate the brush from the torsion spring 34 so that the front and rear ends of the brush 33 are displaced in the axial direction of the commutator 16. The brush 33 to which the rotational force is applied is inclined in the axial direction of the commutator 16 with respect to the brush holder 32 inside the brush holder 32, and is pressed against the first inner surface S1 at the tip side. Then, the rear end side comes into contact with and pressed against the second inner surface S2. The tip of the brush 33 protrudes from the inner opening 32h into the cover 25, and the first inner surface S1 extends radially inward to the inner opening 32h. Therefore, on the tip end side of the brush 33, the first side surface 33 a of the brush 33 is in line contact with the linear portion 72.

Next, the operation of the motor 1 provided with the brush device 31 of the present embodiment will be described.
In each brush device 31, the brush 33 is in line contact with the first inner surface S <b> 1 because the brush 33 contacts the linear portion 72 on the tip side. The straight portion 72 has a linear shape that is orthogonal to the axial direction of the commutator 16 and orthogonal to the direction in which the brush holder 32 extends. Accordingly, when the brush 33 is pressed against the linear portion 72 on the tip side of the brush 33 by the urging force of the torsion spring 34 and makes a line contact with the linear portion 72, the posture becomes more stable.

As described above, the second embodiment has the following effects in addition to the same effects as (1) to (7) of the first embodiment.
(8) In each brush device 31, when the brush 33 is pressed against the linear portion 72 on the tip side of the brush 33 by the urging force of the torsion spring 34 and makes a line contact with the linear portion 72, the posture becomes more stable. . Therefore, shakiness of the brush 33 can be further suppressed, and the brush 33 can be brought into contact with the commutator 16 in a more stable state.

Each embodiment of the present invention may be modified as follows.
In each of the above embodiments, the motor 1 is used as a drive source for a power window device that moves the window glass of a vehicle up and down electrically. However, the motor 1 may be used as a drive source for devices other than the power window device. Moreover, you may provide the brush apparatus 31 in the motor which is not provided with the deceleration part.

  In the second embodiment, the brush 33 is in line contact with the linear portion 72 on the tip side. However, when the straight part 72 has a width, the brush 33 may be in surface contact with the straight part 72 on the tip side. Even in this case, the same effect as (8) of the second embodiment can be obtained. Further, when the brush 33 is pressed against the second inner surface S2 on the tip side by the urging force of the torsion spring 34, the commutator 16 is connected to the end of the second inner surface S2 on the commutator 16 side. A linear portion 72 may be provided that forms a straight line that is perpendicular to the axial direction of the brush holder 32 and perpendicular to the direction in which the brush holder 32 extends.

  In each of the above embodiments, the tracking recess 33 h is formed at the rear end of the brush 33. However, the brush 33 does not necessarily have to include the tracking recess 33h. In this case, an even number of convex portions projecting toward the rear end portion side of the brush 33 and spaced apart in the circumferential direction of the commutator 16 are formed on the pressing portion 34 c of the torsion spring 34, and the convex portion is formed at the rear end portion of the brush 33. Even portions spaced apart in the circumferential direction of the commutator 16 may be pressed. If it does in this way, it can control that brush 33 rattles (runs out) in the peripheral direction of commutator 16 inside brush holder 32. Further, the pressing portion of the brush 33 by the convex portion is set to a position shifted from the center line L2 in the axial direction of the commutator 16 at the rear end portion of the brush 33, and the pressing portion of the brush 33 by the convex portion is set to the position of the commutator 16. When the same number is provided on both sides of the straight line L3 when viewed from the axial direction, the brush 33 can be brought into contact with the commutator 16 in a more stable state.

  In the first embodiment, the pigtail 35 is connected at the rear end of the brush 33 to the opposite side of the center line L2 with respect to the pressing position of the brush 33 by the torsion spring 34 (ie, the pressing points P4 and P5). Has been. However, the pigtail 35 may be connected to a position different from that of the first embodiment as long as it is connected to the rear end portion of the brush 33. For example, the pigtail 35 may be connected to the circumferential side surface of the commutator 16 at the rear end of the brush 33. The same applies to the brush device 31 of the second embodiment.

  In the first embodiment, the torsion spring 34 presses the position on the one end side in the axial direction of the commutator 16 (the yoke 11 side) with respect to the center line L2 at the rear end portion of the brush 33. The brush 33 is in contact with the commutator 16 on the other end side in the axial direction of the commutator 16 (the speed reduction portion side) than the center line L2. However, as shown in FIG. 11, the brush 33 may contact the commutator 16 at one axial end side (the yoke 11 side) of the commutator 16 with respect to the center line L2. In FIG. 11, the same code | symbol is attached | subjected to the structure similar to the said 1st Embodiment. In the example shown in FIG. 11, the torsion spring 34 biases the brush 33 in a direction substantially parallel to the diameter direction of the commutator 16. Further, when viewed from the circumferential direction of the commutator 16 (that is, the state shown in FIG. 11), the pressing points P4 and P5 of the brush 33 by the torsion spring 34 and the contact point P1 between the brush 33 and the commutator 16 are the commutator. 16 is displaced in the axial direction. Even if it does in this way, the effect similar to (1) and (4) of the said 1st Embodiment can be acquired. The same applies to the brush device 31 of the second embodiment.

  In the first embodiment, the first inner surface S <b> 1 and the second inner surface S <b> 2 are inclined toward the commutator 16 toward one end side (yoke side) in the axial direction of the commutator 16. The torsion spring 34 presses the position on the one end side (yoke side) in the axial direction of the commutator 16 with respect to the center line L2 at the rear end portion of the brush 33. However, as shown in FIG. 12, the torsion spring 34 may press the position on the other end side in the axial direction of the commutator 16 (the speed reduction portion side) with respect to the center line L <b> 2 at the rear end portion of the brush 33. In FIG. 12, the same code | symbol is attached | subjected to the structure similar to the said 1st Embodiment. In the example shown in FIG. 12, the torsion spring 34 biases the brush 33 in a direction substantially parallel to the diameter direction of the commutator 16. Further, when viewed from the circumferential direction of the commutator 16 (that is, the state shown in FIG. 12), the pressing points P4 and P5 of the brush 33 by the torsion spring 34 and the contact point P1 between the brush 33 and the commutator 16 are the commutator. 16 is displaced in the axial direction. And the rotational force of the arrow (beta) direction is provided to the brush 33 by component force F1b and component force F2b. Even if it does in this way, the effect similar to (1) of the said 1st Embodiment can be acquired. The same applies to the brush device 31 of the second embodiment.

  In addition, as shown in FIG. 13, when the torsion spring 34 presses the position on the other end side in the axial direction of the commutator 16 (the speed reduction portion side) with respect to the center line L <b> 2 at the rear end portion of the brush 33. The contact portion (ie, contact point P1) between the commutator 16 and the commutator 16 may be set closer to one end side (yoke side) in the axial direction of the commutator 16 than the center line L2. In FIG. 13, the same code | symbol is attached | subjected to the structure similar to the said 1st Embodiment. In the example shown in FIG. 13, the torsion spring 34 biases the brush 33 in a direction substantially parallel to the diameter direction of the commutator 16. Further, when viewed from the circumferential direction of the commutator 16 (that is, the state shown in FIG. 13), the pressing points P4 and P5 of the brush 33 by the torsion spring 34 and the contact point P1 between the brush 33 and the commutator 16 are the commutator. 16 is displaced in the axial direction. And the rotational force of the arrow (beta) direction is provided to the brush 33 by component force F1b and component force F2b. Even if it does in this way, the effect similar to (1) of the said 1st Embodiment can be acquired. The same applies to the brush device 31 of the second embodiment.

  In each of the above embodiments, the first inner side surface S1 and the second inner side surface S2 are inclined toward the commutator 16 toward one end side (yoke side) in the axial direction of the commutator 16. However, the first inner side surface S1 and the second inner side surface S2 are formed so as to be inclined toward the commutator 16 toward both ends of the commutator 16 in the axial direction toward the end on the speed reduction unit 3 side. Also good. In this case, one end side of the commutator 16 in the axial direction is the speed reduction unit 3 side of the commutator 16. Further, the first inner side surface S1 and the second inner side surface S2 may be formed orthogonal to the axial direction of the commutator 16 (parallel to the diameter direction of the commutator 16). Also in these cases, the position shifted in the axial direction of the commutator 16 from the center line L2 at the rear end portion of the brush 33 is pressed by the torsion spring 34, the pressed portion of the brush 33 by the torsion spring 34, and the brush 33 By shifting the contact point with respect to the commutator 16 in the axial direction of the commutator 16, the same effect as (1) of the first embodiment can be obtained.

The number of brush devices 31 provided in the motor 1 is not limited to two and may be three or more.
The technical ideas that can be grasped from each of the above embodiments and each of the above modifications will be described below.

  (B) A brush holder extending in a substantially radial direction of the commutator, a brush accommodated in a state having a gap in the brush holder and having a tip contacting the commutator, and a rear end portion of the brush as the commutator A brush device comprising: a torsion spring biased toward the brush, wherein the torsion spring presses even-numbered portions spaced apart in the circumferential direction of the commutator at a rear end portion of the brush. apparatus. According to this configuration, it is possible to prevent the brush from rattling in the circumferential direction of the commutator inside the brush holder.

  (B) In the brush device according to (A), the brush contacts the commutator at one location, and a location where the brush is pressed by the torsion spring is viewed from the axial direction of the commutator, The brush device is characterized in that the same number is provided on both sides of a straight line passing through a contact portion between the brush and the commutator and parallel to the center line of the brush. According to this configuration, the brush can be brought into contact with the commutator in a more stable state.

  (C) In the brush device according to (b), a trailing recess is formed at the rear end of the brush on the side opposite to the tip of the brush, and the rectification is formed at one end of the torsion spring. A pressing that protrudes in a circular arc shape toward the rear end of the brush as viewed from the axial direction of the child, and that is inserted into the tracking recess and presses two locations spaced apart in the circumferential direction of the commutator on the inner peripheral surface of the tracking recess A brush device, wherein convex portions are formed. According to this configuration, the pressing convex portion presses two locations that are inserted in the tracking recess and spaced apart in the circumferential direction of the commutator on the inner peripheral surface of the tracking recess. When the brush wears, the rear end portion of the brush moves toward the commutator, and accordingly, one end portion where the pressing convex portion of the torsion spring is formed rotates around the coil portion of the torsion spring as the center of rotation. Thus, even if the one end portion where the pressing convex portion is formed in the torsion spring rotates, the pressing convex portion forms an arc shape protruding toward the rear end portion side of the brush when viewed from the axial direction of the commutator. It is possible to maintain a state in which two locations spaced apart in the circumferential direction of the commutator are pressed by the pressing convex portion on the inner peripheral surface of the tracking concave portion. Therefore, even if the brush is worn, it is possible to suppress the rattling of the brush in the circumferential direction of the commutator.

  (D) a brush holder having a pair of inner side surfaces spaced apart in the axial direction of the commutator and extending in a substantially radial direction of the commutator; and being accommodated in a state having a gap in the brush holder and having a tip contacting the commutator And a torsion spring that urges a rear end portion of the brush toward the commutator, wherein the torsion spring is a center line of the brush at the rear end portion of the brush. The brush is biased toward the commutator by pressing a position shifted in the axial direction of the commutator from the pressing portion of the brush by the torsion spring, and the contact portion of the brush with respect to the commutator, Is displaced in the axial direction of the commutator, and the brush is biased by the torsion spring, so that one of the pair of inner side surfaces at the tip side is Contacts with the side surface, a brush apparatus characterized by being in contact with the rear end side to the other of the inner surface. According to this configuration, by energizing the brush with the torsion spring, it is possible to apply a rotational force to the brush so as to rotate the brush so that the front end and the rear end of the brush are displaced in the axial direction of the commutator. The brush to which the rotational force is applied is in contact with and pressed against one inner surface on the tip side, and in contact with the other inner surface on the rear end side. Therefore, since it becomes difficult for the brush to move in the axial direction of the commutator within the brush holder, it is possible to suppress rattling of the brush in the axial direction of the commutator. Further, the brush can be brought into contact with the commutator in a stable state. In addition, the backlash of the brush in the brush holder is suppressed by pressing the position shifted in the axial direction of the commutator from the brush center line by the torsion spring at the rear end of the brush. It does not have to be increased.

The technical idea is described below.
A brush holder having a pair of inner side surfaces spaced apart in the axial direction of the commutator and extending in a substantially radial direction of the commutator, and being accommodated in a state having a gap in the brush holder, the tip contacts the commutator A brush device comprising: a brush; and a torsion spring that urges a rear end portion of the brush toward the commutator, wherein the pair of inner side surfaces are directed to the commutator and the axis of the commutator The torsion spring is pushed toward the commutator by pressing the position of the commutator on the one end side in the axial direction with respect to the center line of the brush at the rear end of the brush. The brush is urged by the torsion spring, so that it contacts the inner side surface on the other end side in the axial direction of the commutator among the pair of inner side surfaces at its tip side, The inner end surface of the commutator is in contact with the inner surface on one axial end side of the commutator, and the center line is placed on the rear end side portion of the brush with respect to the pressing position of the brush by the torsion spring. A pigtail for supplying power to the brush is connected to the opposite side of the clip.

  According to this configuration, the torsion spring presses the position on the one end side in the axial direction of the commutator with respect to the center line of the brush at the rear end portion of the brush. Therefore, it is easy to apply a rotational force to the brush to rotate the brush so that the front end and the rear end of the brush are displaced in the axial direction of the commutator. The brush to which the rotational force is applied is pressed against the inner surface on the other end side in the axial direction of the commutator on the tip side, and is pressed on the inner surface on the one end side in the axial direction of the commutator on the rear end side. It will be in the state pressed by contact. Therefore, since it becomes difficult for the brush to move in the axial direction of the commutator within the brush holder, it is possible to suppress rattling of the brush in the axial direction of the commutator. Further, the brush can be brought into contact with the commutator in a stable state. Furthermore, since the back end portion of the brush presses the position of one end of the commutator in the axial direction with respect to the center line of the brush with a torsion spring, the backlash of the brush in the brush holder is suppressed. Need not be increased.

  Further, when the torsion spring urges the rear end of the brush in a direction substantially parallel to the diameter direction of the commutator, the brush is easily rotated so that the front end and the rear end thereof are displaced in the axial direction of the commutator. The tip side can contact the inner side surface of the commutator in the axial direction other end side, and the rear end side can contact the inner side surface of the commutator in the axial direction one end side. Therefore, since the urging direction of the brush by the torsion spring does not need to be a complicated direction, the structure of the brush device is prevented from being complicated.

  Further, the force generated by the torsion spring biasing the brush is substantially the same as the rotational force that rotates the brush so that the tip and rear ends of the brush are displaced in the axial direction of the commutator. To the brush. Therefore, since it becomes difficult for the brush to move further in the axial direction of the commutator within the brush holder, it is possible to further suppress the rattling of the brush in the axial direction of the commutator.

The brush contacts the commutator at the other axial end of the commutator from the center line.
According to this configuration, it is easy to increase the rotational force that is generated when the torsion spring biases the brush so as to rotate the brush so that the front end and the rear end of the brush are displaced in the axial direction of the commutator. Therefore, the brush can be strongly pressed against the inner surface on the other end in the axial direction of the commutator at the tip end of the brush, and the brush can be pressed more strongly against the inner surface on the one end in the axial direction of the commutator. it can. Therefore, since it becomes more difficult for the brush to move in the axial direction of the commutator inside the brush holder, it is possible to further suppress rattling of the brush in the axial direction of the commutator.

  The brush contacts the commutator at one location, and the torsion spring presses the even-numbered locations spaced apart in the circumferential direction of the commutator at the rear end of the brush, and the brush by the torsion spring The same number of pressing points are provided on both sides of a straight line that passes through the contact point between the brush and the commutator and is parallel to the center line when viewed from the axial direction of the commutator.

According to this configuration, it is possible to prevent the brush from rattling in the circumferential direction of the commutator inside the brush holder.
A follow-up concave portion that is opened to the opposite side of the brush tip is formed at the rear end portion of the brush, and the brush rear end portion as viewed from the axial direction of the commutator is formed at one end portion of the torsion spring. A pressing convex portion is formed which protrudes in an arc shape on the side and presses two locations spaced in the circumferential direction of the commutator on the inner peripheral surface of the tracking concave portion.

  According to this configuration, the pressing convex portion presses two locations that are inserted in the tracking recess and spaced apart in the circumferential direction of the commutator on the inner peripheral surface of the tracking recess. When the brush wears, the rear end portion of the brush moves toward the commutator, and accordingly, one end portion where the pressing convex portion of the torsion spring is formed rotates around the coil portion of the torsion spring as the center of rotation. Thus, even if the one end portion where the pressing convex portion is formed in the torsion spring rotates, the pressing convex portion forms an arc shape protruding toward the rear end portion side of the brush when viewed from the axial direction of the commutator. It is possible to maintain a state in which two locations spaced apart in the circumferential direction of the commutator are pressed by the pressing convex portion on the inner peripheral surface of the tracking concave portion. Therefore, even if the brush is worn, it is possible to suppress the rattling of the brush in the circumferential direction of the commutator.

  The inner side surface on the other end side in the axial direction of the commutator that contacts the tip end side of the brush among the pair of inner side surfaces is perpendicular to the axial direction of the commutator at the end of the inner surface on the commutator side And a linear portion that forms a straight line perpendicular to the direction in which the brush holder extends, and the brush is in contact with the linear portion on the tip side.

  According to this configuration, since the brush contacts the linear portion at the tip end side, the brush can make line contact or surface contact with the inner surface. The straight portion has a linear shape that is orthogonal to the axial direction of the commutator and orthogonal to the direction in which the brush holder extends. Therefore, when the brush is pressed against the linear portion on the tip side of the brush by the urging force of the torsion spring and makes line contact or surface contact with the linear portion, the posture becomes more stable. Therefore, shakiness of the brush can be further suppressed, and the brush can be brought into contact with the commutator in a more stable state.

The motor is provided with the commutator fixed so as to be integrally rotatable with a rotary shaft that is rotationally driven, and the brush device having the brush that is in sliding contact with the outer peripheral surface of the commutator.
According to this configuration, since the motor includes the brush device in which the rattling of the brush in the brush holder is suppressed, the generation of noise due to the rattling of the brush is suppressed in this motor. Further, since the brush is in contact with the commutator in a stable state, excessive wear of the brush is suppressed and the life of the brush is shortened. Accordingly, it is possible to suppress the life of the motor from being shortened.

  DESCRIPTION OF SYMBOLS 13 ... Rotary shaft, 16 ... Commutator, 31 ... Brush apparatus, 32 ... Brush holder, 33 ... Brush, 33h ... Follow-up recessed part, 34 ... Torsion spring, 34d ... Pressing convex part, 35 ... Pigtail, 72 ... Linear part, L2 ... center line, L3 ... straight line, S1 ... first inner side as inner side, S2 ... second inner side as inner side.

Claims (2)

A brush holder that is provided in a cylindrical cover portion that accommodates the commutator and has a pair of inner side surfaces that are spaced apart in the axial direction of the commutator and extends in a substantially radial direction of the commutator;
A brush housed in a state having a gap in the brush holder and having a tip contacting the commutator;
A torsion spring that biases the rear end of the brush toward the commutator;
A brush device comprising:
The torsion spring urges the brush toward the commutator by pressing a position shifted in the axial direction of the commutator from the center line of the brush at the rear end of the brush,
The brush is biased by the torsion spring, so that one of the pair of inner side surfaces is brought into contact with the tip side and the other side surface is brought into contact with the rear end side. Configured,
Of the pair of inner side surfaces, the inner side surface that is in contact with the tip side of the brush is perpendicular to the axial direction of the commutator when viewed from the axial direction of the commutator at the end of the inner surface on the commutator side. And it has a straight line portion that forms a straight line perpendicular to the direction in which the brush holder extends, and the brush is configured to contact the straight line portion on its tip side,
An end portion on the radially inner side of the brush holder protrudes on the inner side of the cover portion, and an inner opening portion that opens on the inner side of the cover portion is formed on the end portion on the radially inner side of the brush holder. The brush device is characterized in that the straight line portion constitutes a part of the inner opening. The commutator fixed so as to rotate integrally with a rotary shaft that is driven to rotate;
The brush device according to claim 1, comprising the brush slidably in contact with an outer peripheral surface of the commutator.