JP2019009876A - Motor device - Google Patents

Abstract

To provide a motor device capable of suppressing electromagnetic noise discharged externally.SOLUTION: On a side surface of a coupling section between a first case 13 and a second case 41, an opening 49 is formed by the second case 41 having a concave shape in a shaft direction, and part of a flange section 36 of a brush holder 31 is exposed to outside from the opening 49. At the opening 49, a conductive shield cap 51 (an electromagnetic shield unit) electrically connected with the first and second cases 13, 41 is provided so as to cover the opening 49.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a motor device.

  Conventionally, for example, in the motor device disclosed in Patent Document 1, a motor yoke that rotatably accommodates a rotating body having a commutator and a gear case that accommodates a reduction mechanism that decelerates rotation of the rotating body are integrally assembled. Composed. A resin brush holder is provided between the motor yoke and the gear case to hold a brush that is in sliding contact with the commutator so that a part of the brush holder is held between the motor yoke and the gear case in the axial direction. It has become. Here, in the motor device of Patent Document 1, an opening is formed on the side surface of the coupling portion (joint portion) between the motor yoke and the gear case by forming a shape in which the gear case side is recessed in the axial direction. A part of the brush holder is exposed to the outside through the opening.

JP 2017-34808 A

  In the motor device as disclosed in Patent Document 1, electromagnetic noise generated by the sliding contact between the brush and the commutator may be discharged to the outside from the opening in the connecting portion between the motor yoke and the gear case. In recent years, when better EMC (electromagnetic compatibility) performance is required, further study on the electromagnetic noise of the motor device is required.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a motor device capable of suppressing electromagnetic noise emitted to the outside.

  A motor device that solves the above-described problem is composed of a rotating body having a commutator, a first case that is made of a conductive material, and that rotatably accommodates the rotating body, and is made of a conductive material, and is connected to the first case. A second case, a brush holder made of a non-conductive material, and at least partly held in the axial direction by the first case and the second case, and held by the brush holder and slid on the commutator. An opening is formed on the side surface of the connecting portion between the first case and the second case by forming a shape in which at least one of the first and second cases is recessed in the axial direction. A motor device in which a part of the brush holder is exposed to the outside from the opening, covers at least a part of the opening, and is electrically connected to at least one of the first and second cases. Conductivity It is equipped with an electromagnetic shield portion.

  According to this structure, it can suppress by the electromagnetic shield part that the electromagnetic noise produced by the sliding contact of a brush and a commutator is discharge | released outside from the opening part in the connection part of a 1st case and a 2nd case.

In the motor device, the electromagnetic shield part is a shield cap that is mounted so as to cover at least a part of the opening.
According to this configuration, electromagnetic noise emitted from the opening can be suppressed with a simple configuration.

In the motor device, the shield cap includes a retaining claw for preventing the retaining cap to be engaged with any of the first case, the second case, and the brush holder.
According to this configuration, the shield cap can be suitably fixed by the locking claw, and as a result, the shield cap can be prevented from falling off.

  In the motor device, the brush holder includes an extending portion that enters the opening, and the shield cap includes a first sandwiched portion that is sandwiched between the extending portion and the first case in the axial direction. And a second sandwiched portion that is sandwiched between the extending portion and the second case in the axial direction.

  According to this configuration, the first sandwiched portion is sandwiched between the extension portion of the brush holder and the first case, and the second sandwiched portion is sandwiched between the extension portion of the brush holder and the second case. The shield cap can be suitably fixed, and as a result, the shield cap can be prevented from falling off.

  In the motor device, the brush holder and the electromagnetic shield part are configured as an integrally molded product, and at least a part of the electromagnetic shield part is embedded in the brush holder.

  According to this configuration, since the brush holder and the electromagnetic shield portion are configured as an integrally molded product, an increase in the number of components can be suppressed. In addition, since at least a part of the electromagnetic shield part is embedded in the brush holder, the electromagnetic shield part is stably held, and as a result, dropping of the electromagnetic shield part can be suppressed.

In the motor device, the brush holder has an extending part that enters the opening, and the electromagnetic shield part is a conductive coating film coated on the surface of the extending part.
According to this configuration, it is possible to suppress electromagnetic noise emitted from the opening while suppressing an increase in the number of parts. Moreover, since the electromagnetic shield part is made of a conductive coating film, it is possible to suppress the electromagnetic shield part from falling off due to vibration or the like.

  In the motor device, the outer surface of the electromagnetic shield part is positioned so as to be flush with the outer surface of the connecting portion of the first case and the second case, or the outer surface of the electromagnetic shield part is It is located radially inward from the outer surface of the connecting portion of the first case and the second case.

  According to this structure, it can be set as the structure by which an electromagnetic shield part does not protrude to the radial direction outer side from the outer surface in the connection part of a 1st and 2nd case. Thereby, the enlargement to the radial direction of a motor apparatus can be suppressed, and the mounting property of a motor apparatus can be improved by extension.

  According to the motor device of the present invention, electromagnetic noise emitted to the outside can be suppressed.

The side view which shows the motor apparatus of embodiment partially in a cross section. The side view of the motor apparatus of the same form. (A) The side view of the brush holder of the same form, (b) The top view of the brush holder. Sectional drawing which shows a part of motor apparatus of the same form. (A) The side view which shows a part of motor device of a modification, (b) The 5b-5b sectional view taken on the line in the same figure (a). Sectional drawing which shows a part of motor apparatus of a modification. Sectional drawing which shows a part of motor apparatus of a modification. (A) The side view which shows a part of motor device of a modification, (b) The 8b-8b sectional view taken on the line in the same figure (a). (A) The side view which shows a part of motor apparatus of a modification, (b) The 9b-9b sectional view taken on the line in the same figure (a).

  Hereinafter, an embodiment of a motor device will be described with reference to FIGS. In the drawing, three directions orthogonal to each other are shown as an X direction, a Y direction, and a Z direction. Specifically, the axial direction of the motor device (the axial direction of the rotating shaft 21 described later) is illustrated to be parallel to the Z direction, and the axial direction of the output shaft 43 described later is illustrated to be parallel to the Y direction. It is shown that the direction orthogonal to the axial direction of the rotating shaft 21 and the axial direction of the output shaft 43 is parallel to the X direction. Further, in the following description, unless otherwise specified, when “axial direction”, “radial direction”, and “circumferential direction” are simply described, the axial direction, radial direction, circumferential direction of the motor device (rotating shaft 21) are described. Each direction shall mean.

  The motor device 10 of this embodiment shown in FIGS. 1 and 2 is a motor with a brush, and is, for example, a rear wiper motor used as a drive source of a device for wiping the rear glass of a vehicle. The motor device 10 includes a motor main body 11 that generates a rotational force, and an output unit 12 that decelerates and outputs the rotation of the motor main body 11.

The motor body 11 includes a first case 13, a magnet 14, an armature 15 as a rotating body, and a brush device 16.
The first case 13 is made of a conductive material such as metal, and has a bottomed cylindrical shape with one axial end (the right end in FIG. 1) closed. Specifically, the first case 13 includes a cylindrical outer peripheral wall 13a and a bottom portion 13b that closes one axial end of the outer peripheral wall 13a. The outer peripheral wall 13a has a thin flat shape in the Y direction orthogonal to the axial direction (Z direction). That is, the outer peripheral wall 13a is set so that the dimension in the Y direction (see FIG. 2) is shorter than the dimension in the X direction (see FIG. 1). Further, the outer peripheral wall 13a has a two-sided width shape including a pair of flat surface portions orthogonal to the Y direction and a pair of curved surface portions connecting the ends of the pair of flat surface portions. Note that the curved surface portion has a curved surface shape that bulges outward in the radial direction (swells in an arc shape around the axis of the rotation shaft 21).

  Further, the first case 13 has a flange portion 13d extending in the axial orthogonal direction from the axially open end portion 13c (end portion on the opposite side to the bottom portion 13b) of the outer peripheral wall 13a. The first case 13 is formed from a metal plate by pressing or the like, and the flange portion 13d is integrated with the outer peripheral wall 13a.

  As shown in FIG. 1, FIG. 2, FIG. 3 (b) and FIG. 4, the flange portion 13d has a dimension in the Y direction shorter than the dimension in the X direction, like the outer peripheral wall 13a. The dimension of the flange portion 13d in the Y direction is set to be slightly larger than the dimension of the outer peripheral wall 13a in the Y direction (see FIGS. 2 and 4). Further, both side edge portions 13e in the Y direction of the flange portion 13d extend in the Y direction from the planar portion of the outer peripheral wall 13a, and are formed in a straight line parallel to the X direction (a planar portion of the outer peripheral wall 13a). ing.

As shown in FIG. 1, a magnet 14 is fixed to the inner peripheral surface of the outer peripheral wall 13 a of the first case 13, and an armature 15 is rotatably disposed inside the magnet 14 in the radial direction.
The armature 15 includes a rotating shaft 21, an armature core 22 fixed to the rotating shaft 21 so as to be integrally rotatable, a coil 23 wound around the armature core 22, and a rotatable shaft 21. A commutator 24 that is fixed and electrically connected to the coil 23 is provided. The base end portion of the rotating shaft 21 is pivotally supported by a bearing 25 provided at the center of the bottom portion 13 b of the first case 13. Further, the distal end portion of the rotating shaft 21 protrudes from the opening end portion 13 c to the outside of the first case 13. The armature core 22 is provided on the radially inner side of the magnet 14. The commutator 24 is provided on the distal end side of the rotating shaft 21 with respect to the armature core 22. The commutator 24 has a cylindrical shape, and a plurality of segments (not shown) are juxtaposed in the circumferential direction on the outer peripheral surface of the commutator 24.

  A brush device 16 is attached to the open end 13 c of the first case 13. The brush device 16 includes a brush holder 31, a pair of brushes 32 held by the brush holder 31, and a connector portion 33 extending from the brush holder 31 in the direction perpendicular to the axis (X direction). The brush holder 31 is mainly formed of a nonconductive material such as resin.

  As shown in FIGS. 3A and 3B, the brush holder 31 has a holder main body 34 in which a part in the axial direction is accommodated inside the outer peripheral wall 13 a of the first case 13. The holder main body 34 has a two-sided width shape in which the outer shape viewed from the axial direction corresponds to the outer peripheral wall 13a (opening end 13c) of the first case 13 (see FIG. 3B). In other words, the holder body 34 is set so that the dimension in the Y direction is shorter than the dimension in the X direction.

  As shown in FIGS. 1 and 3 (b), the holder main body 34 includes a pair of brush accommodating portions 35. Each brush accommodating portion 35 accommodates a brush 32 so as to be in contact with the outer peripheral surface (segment) of the commutator 24 (see FIG. 1). Each brush 32 is disposed at an opposing position of 180 degrees on the outer periphery of the commutator 24. One brush 32 is disposed on one side in the X direction with respect to the commutator 24, and the other brush 32 is disposed on the other side in the X direction with respect to the commutator 24. Further, the commutator 24 and each brush 32 are disposed inside the outer peripheral wall 13 a of the first case 13. Each brush 32 is urged toward the commutator 24 (in the radial direction) by a spring (not shown). In addition, various electronic components electrically connected to the brushes 32 are mounted on the holder main body 34.

  As shown in FIGS. 3A and 3B, the brush holder 31 includes a flange portion 36 that extends radially outward from the outer peripheral surface of the holder main body portion 34. The flange portion 36 is provided over the entire outer periphery of the holder main body portion 34, and the outer shape of the flange portion 36 viewed from the axial direction is a shape that follows the holder main body portion 34 (open end portion 13c of the first case 13). There is no. That is, both side edge portions 36a in the Y direction of the flange portion 36 are linearly parallel to the X direction. Note that the outer shape of the flange portion 36 viewed from the axial direction is slightly larger than the opening end portion 13 c of the first case 13. And the holder main-body part 34 and the flange part 36 of the brush holder 31 are provided so that the opening end part 13c of the 1st case 13 may be obstruct | occluded substantially.

  Both end surfaces in the axial direction of the flange portion 36 are flat surfaces perpendicular to the axial direction. And each side edge part 36a of the flange part 36 is provided with three convex parts 36b and 36c which each protrude in an axial direction from the axial direction both end surfaces. Each protrusion 36b protrudes toward the first case 13 in the axial direction, and each protrusion 36c protrudes toward the second case 41 described later in the axial direction. Further, in each side edge portion 36a, one convex portion 36b is provided at the center in the X direction of the side edge portion 36a and one at each end portion in the X direction of the side edge portion 36a. Each convex portion 36c is provided at a position overlapping with each convex portion 36b in the axial direction.

  As shown in FIG. 3B, each side edge portion 36a of the flange portion 36 is formed with a pair of through holes 36d penetrating in the axial direction. Each through-hole 36d has a long hole shape extending in the X direction. Moreover, each through-hole 36d is provided between the convex part 36b (convex part 36c) in a X direction.

  The connector portion 33 is formed integrally with the brush holder 31 and is provided so as to extend from the flange portion 36 of the brush holder 31 in the axis orthogonal direction (X direction). A plurality of terminals 37 are embedded in the brush holder 31 by insert molding or the like. Each terminal 37 is provided from the holder main body 34 to the connector 33. Each terminal 37 is electrically connected to each brush 32. An external connector (not shown) connected to the connector portion 33 is electrically connected to each terminal 37.

  As shown in FIG. 1, the output unit 12 includes a second case 41 connected to the first case 13, a speed reduction mechanism 42 accommodated in the second case 41, and an output shaft 43 connected to the speed reduction mechanism 42. It has.

  The second case 41 is made of a conductive material such as metal. The second case 41 includes a connecting portion 45 that is fixed by the flange portion 13 d of the first case 13 and a plurality of screws 44, and an accommodating portion 46 that extends from the connecting portion 45 in the axial direction. A deceleration mechanism 42 is accommodated in the accommodating portion 46. Similar to the first case 13, the connecting portion 45 and the accommodating portion 46 have a thin flat shape in the Y direction.

  The connecting portion 45 has an outer peripheral wall 47 erected in the axial direction, and an axial front end surface of the outer peripheral wall 47 is in contact with the flange portion 13 d of the first case 13 in the axial direction. A part of the holder main body 34 in the brush holder 31 in the axial direction and the flange 36 are accommodated inside the outer peripheral wall 47 of the connecting portion 45. Further, the distal end portion of the rotating shaft 21 enters the outer peripheral wall 47.

  The space inside the connecting portion 45 (inside the outer peripheral wall 47) and the space inside the accommodating portion 46 are in communication with each other. The speed reduction mechanism 42 housed in the housing portion 46 includes a worm shaft 42a that is coupled to the rotary shaft 21 so as to rotate integrally therewith, and a worm wheel 42b that meshes with the worm shaft 42a. The worm shaft 42 a is arranged coaxially with the rotary shaft 21. The rotation axis of the worm wheel 42b is set parallel to the Y direction. Further, the speed reduction mechanism 42 includes a link mechanism 42c that transmits the rotation of the worm wheel 42b to the output shaft 43 and reciprocally rotates the output shaft 43. The axis of the output shaft 43 is parallel to the Y direction (that is, parallel to the rotational axis of the worm wheel 42b) (see also FIG. 2). A rear wiper (not shown) is fixed to the output shaft 43.

  As shown in FIG. 2, the output shaft 43 protrudes from the second case 41 to the front side in the Y direction (on the side opposite to the opening of the second case 41 in the drawing). The second case 41 is fixed to the vehicle body panel P by a plurality of screws Pa on the back surface 12a side in the Y direction (opening side of the second case 41). The vehicle body panel P is configured to cover the outer side of the connecting portion 45 in the radial direction (Y direction).

Next, the connecting portion 45 of the second case 41 will be described in detail.
As shown in FIGS. 1 and 2, the shape of the outer peripheral wall 47 of the connecting portion 45 viewed from the axial direction is a shape that substantially follows the flange portion 13 d of the first case 13. That is, the outer peripheral wall 47 has a pair of linear portions 47a extending linearly in parallel with the X direction when viewed from the axial direction. And each linear part 47a is comprised so that it may overlap with each side edge part 13e of the flange part 13d in an axial direction (refer FIG. 4). The dimension in the Y direction of the outer peripheral wall 47 is set to be equal to the dimension in the Y direction of the flange portion 13 d of the first case 13.

  As shown in FIG. 1, each linear portion 47 a of the outer peripheral wall 47 is formed with a concave portion 48 that is recessed in the axial direction from the axial front end surface of the outer peripheral wall 47. The concave portion 48 is formed so as to communicate the inner and outer sides of the outer peripheral wall 47 (linear portion 47a) in the radial direction (Y direction). That is, in the present embodiment, the concave portion 48 is provided on the second case 41 side, so that both end surfaces in the Y direction at the connecting portions (joint portions) of the first and second cases 13 and 41 are arranged in the Y direction. Opening portions 49 that open are formed. The opening shape of the opening 49 is a rectangular shape having a pair of long sides parallel to the X direction and a pair of short sides parallel to the Z direction (axial direction).

  As shown in FIGS. 3A and 4, the side edge portions 36 a of the flange portion 36 of the brush holder 31 enter into the openings 49. The side edge portion 36 a of the flange portion 36 is sandwiched in the axial direction by the side edge portion 13 e of the flange portion 13 d (first case 13) and the bottom surface of the concave portion 48 of the second case 41. In the present embodiment, each convex portion 36b of each side edge portion 36a abuts on the side edge portion 13e of the flange portion 13d in the axial direction, and each convex portion 36c of each side edge portion 36a is a concave portion of the second case 41. 48 is in axial contact with the bottom surface of 48. That is, between the one end surface in the axial direction of the side edge portion 36 a and the side edge portion 13 e of the flange portion 13 d (first case 13), and between the other end surface in the axial direction of the side edge portion 36 a and the concave portion 48 of the second case 41. Clearances are provided between the bottom surface.

  As shown in FIG. 4, the motor device 10 of the present embodiment includes a pair of shield caps 51 (only one is shown in FIG. 4) that respectively closes the pair of openings 49. Each shield cap 51 is made of a conductive material such as metal. Each shield cap 51 is formed in a plate shape perpendicular to the Y direction, a closing portion 52 that closes the opening 49, and first and second sandwiched portions 53 that extend from the closing portion 52 to the inside of the opening 49 in the Y direction. , 54. The closing part 52 has substantially the same shape as the opening part 49. The closing portion 52 covers the radially outer side of the side edge portion 36 a of the flange portion 36 (brush holder 31) located in the opening portion 49.

  The first sandwiched portion 53 extends from the one end in the axial direction of the closing portion 52 (the end on the first case 13 side) to the inside of the opening 49. Further, the second sandwiched portion 54 extends from the other axial end portion (the end portion on the second case 41 side) of the closing portion 52 to the inside of the opening portion 49. And the 1st to-be-clamped part 53 is clamped by the axial direction by the side edge part 13e of the flange part 13d (1st case 13), and the side edge part 36a of the flange part 36 (brush holder 31). Further, the second sandwiched portion 54 is sandwiched in the axial direction by the bottom surface of the recess 48 of the second case 41 and the side edge portion 36a of the flange portion 36 (brush holder 31). In this way, the shield cap 51 is fixed by sandwiching the first and second sandwiched portions 53 and 54. In addition, the 1st to-be-clamped part 53 is located in the radial direction outer side of the convex part 36b of the flange part 36 in the state clamped as mentioned above. Moreover, the 2nd to-be-clamped part 54 is located in the radial direction outer side of the convex part 36c of the flange part 36 in the state clamped as mentioned above.

  The shield cap 51 is in direct contact with the flange portion 13d (side edge portion 13e) of the first case 13 and the concave portion 48 of the second case 41, respectively. Thereby, the shield cap 51 is electrically connected to the first and second cases 13 and 41, respectively.

  Further, as shown in the X direction view (see FIG. 4), the outer surface (radially outer side surface) of the closing portion 52 of the shield cap 51 is the outer surface (radially outer side) of the flange portion 13d (side edge portion 13e). Side surface) and the outer surface (radially outer surface) of the outer peripheral wall 47 (linear portion 47a) so as to be flush with each other. In other words, the outer surfaces of the closing part 52, the flange part 13d (side edge part 13e) and the outer peripheral wall 47 (linear part 47a) are assembled so as to be substantially continuous.

  As for the assembly of the shield cap 51, when the first case 13 and the second case 41 are assembled in such a manner that the brush holder 31 is interposed, each shield cap 51 is attached to each side edge 36a of the flange 36. Thereafter, the first and second cases 13 and 41 may be fixed with screws 44. Alternatively, an assembly procedure for attaching each shield cap 51 after the first and second cases 13 and 41 are fixed with the screws 44 may be used.

Next, the operation of the motor device 10 of this embodiment will be described.
Power from an external connector connected to the connector unit 33 is supplied to the coil 23 via the terminal 37, the brush 32 and the commutator 24. As a result, the armature 15 is rotationally driven, and the rotational driving force of the rotary shaft 21 of the armature 15 is decelerated by the speed reduction mechanism 42 and output from the output shaft 43, whereby the reciprocating rotation of the rear wiper is realized. ing.

  At this time, each brush 32 is brought into sliding contact with the commutator 24 of the rotating armature 15, and electromagnetic noise is generated from the sliding contact portion. Here, since the first and second cases 13 and 41 are made of a conductive material, the first and second cases are not easily leaked to the outside of the first and second cases 13 and 41. Since the opening portion 49 (concave portion 48) is provided in the connecting portion of the 13 and 41, there is a concern about leakage of electromagnetic noise from the opening portion 49. Thus, in the present embodiment, electromagnetic noise is prevented from being emitted from the opening 49 by closing the opening 49 (concave portion 48) with a shield cap 51 made of a conductive material. Further, since the shield cap 51 is electrically connected to the first and second cases 13 and 41, the emission of electromagnetic noise can be more effectively suppressed.

Next, the effect of this embodiment will be described.
(1) An opening 49 is formed on the side surface of the connecting portion between the first case 13 and the second case 41 by forming the second case 41 in a shape that is recessed in the axial direction. A portion (side edge portion 36a) of the flange portion 36 of 31 is exposed to the outside. The opening 49 is provided with a conductive shield cap 51 (electromagnetic shield) electrically connected to the first and second cases 13 and 41 so as to cover the opening 49. According to this configuration, the shield cap 51 can suppress electromagnetic noise generated by the sliding contact between the brush 32 and the commutator 24 from the opening 49.

  (2) As an electromagnetic shield part for electromagnetically shielding the opening 49, a shield cap 51 mounted so as to cover the opening 49 is used. For this reason, the electromagnetic noise emitted from the opening 49 can be suppressed with a simple configuration.

  (3) The brush holder 31 has a flange portion 36 (extending portion) that enters the opening 49. The shield cap 51 includes a first sandwiched portion 53 that is axially sandwiched between the flange portion 36 of the brush holder 31 and the flange portion 13d of the first case 13, and the flange portion 36 of the brush holder 31 and the second case. 41 is provided with a second sandwiched portion 54 that is sandwiched between the outer peripheral wall 47 of the shaft 41 in the axial direction. Thereby, the shield cap 51 can be suitably fixed, and as a result, the drop-off of the shield cap 51 can be suppressed.

  (4) The outer surface (radial outer side surface) of the closing portion 52 of the shield cap 51 is formed between the outer surface (radial outer side surface) of the flange portion 13d (side edge portion 13e) and the outer peripheral wall 47 (linear portion 47a). It is assembled so as to be flush with the outer surface (radially outer surface). Thereby, the enlargement to the Y direction of the motor apparatus 10 can be suppressed, and the mounting property of the motor apparatus 10 can be improved by extension. Moreover, interference with the vehicle body panel P and bracket which fix the motor apparatus 10 can be suppressed.

In addition, you may change the said embodiment as follows.
-As shown to Fig.5 (a) (b), you may provide the latching | locking part 51a which can be latched to the X direction with respect to the side edge part 36a of the flange part 36 (brush holder 31). . As shown in FIG. 5A, the locking portion 51 a is provided at the center portion in the X direction in the closing portion 52 of the shield cap 51. Moreover, as shown in FIG.5 (b), the latching | locking part 51a is formed in the concave shape dented on the outer side of radial direction (Y direction). On the other hand, the side edge portion 36 a of the flange portion 36 is provided with a locking projection 36 e protruding outward in the radial direction (Y direction). The locking projection 36 e is formed on the locking portion 51 a of the shield cap 51. It is inserted. Thereby, the shield cap 51 is locked to the side edge portion 36a of the flange portion 36 in the X direction and the Z direction (axial direction). According to this configuration, the shield cap 51 can be positioned in the X direction and the Z direction with respect to the side edge portion 36a of the flange portion 36, and the assemblability of the shield cap 51 can be improved.

-The fixation aspect of the shield cap 51 is not limited to the said embodiment, It can change suitably.
For example, the configuration may be changed as shown in FIG. In addition, illustration of the convex parts 36b and 36c is abbreviate | omitted in the same figure. In the configuration shown in the figure, the shield cap 51 is provided with first and second retaining claws 55 and 56 for retaining with which the flange portion 36 of the brush holder 31 is retained. The first locking claw 55 extends from the one end in the axial direction of the closing portion 52 (the end on the first case 13 side) to the inside of the opening 49. Further, the second locking claw 56 extends from the other axial end portion (the end portion on the second case 41 side) of the closing portion 52 to the inner side of the opening portion 49. The first and second locking claws 55 and 56 are locked to the outer side in the Y direction with respect to the through hole 36d formed in the side edge portion 36a of the flange portion 36. Thereby, the shield cap 51 can be suitably fixed, and as a result, the drop-off of the shield cap 51 can be suppressed. In the configuration shown in the figure, the portion on the flange portion 36 side that engages with the first and second locking claws 55 and 56 is a through hole 36d. Moreover, it is good also as a convex part which protrudes from the flange part 36 to an axial direction.

  Further, in the configuration shown in FIG. 6, the first and second locking claws 55 and 56 are locked to the flange portion 36 of the brush holder 31, but for example, as shown in FIG. The first and second locking claws 55 and 56 may be locked to the first and second cases 13 and 41, respectively. In the configuration shown in FIG. 7, the first locking claw 55 is locked outward in the Y direction with respect to the locking recess 13 f formed in the first case 13. The second locking claw 56 is locked outward in the Y direction with respect to a locking recess 48 a formed on the bottom surface of the recess 48 of the connecting portion 45 in the second case 41. Thereby, the shield cap 51 can be suitably fixed, and as a result, the drop-off of the shield cap 51 can be suppressed.

  In the configuration shown in FIG. 7, if the first and second locking claws 55 and 56 are configured to elastically contact the first and second cases 13 and 41, respectively, the shield cap 51 and the first The electrical connection between the first and second cases 13 and 41 can be secured more stably.

  In the configuration shown in FIGS. 6 and 7, the first and second locking claws 55, 56 are provided at the axial ends of the closing portion 52, but other than this, for example, the X direction of the closing portion 52 You may provide the 1st and 2nd latching claws 55 and 56 in both ends, respectively.

  Further, the first locking claw 55 may be configured to be sandwiched between the flange portion 36 of the brush holder 31 and the flange portion 13d of the first case 13 in the axial direction. Further, the second locking claw 56 may be configured to be held in the axial direction between the flange portion 36 of the brush holder 31 and the outer peripheral wall 47 of the second case 41 (the bottom surface of the recess 48). According to this configuration, the shield cap 51 can be more stably fixed.

-The structure of the electromagnetic shield part which electromagnetically shields the opening part 49 is not limited to the shield cap 51 of the said embodiment, It can change.
For example, you may change to the structure shown to Fig.8 (a) (b). In the configuration shown in the figure, the brush holder 31 and the electromagnetic shield member 61 as an electromagnetic shield part are configured as an integrally molded product. In this case, for example, an integrally molded product of the brush holder 31 and the electromagnetic shield member 61 can be formed by insert molding using the electromagnetic shield member 61 as an insert product.

  The electromagnetic shield member 61 is made of a conductive material such as metal. The electromagnetic shield member 61 has a flat plate shape that is substantially the same shape as the opening 49, and the electromagnetic shield member 61 is partially embedded in each side edge 36 a of the flange portion 36 (brush holder 31). It is provided as follows. The electromagnetic shield member 61 is provided perpendicular to the Y direction in the opening 49 (in the recess 48). The electromagnetic shield member 61 is in direct contact with the flange portion 13d (side edge portion 13e) of the first case 13 and the concave portion 48 of the second case 41, respectively. Thereby, the electromagnetic shielding member 61 is electrically connected to the first and second cases 13 and 41, respectively.

  According to such a configuration, since the opening 49 is covered with the conductive electromagnetic shield member 61, the electromagnetic noise generated by the sliding contact between the brush 32 and the commutator 24 is released from the opening 49 to the outside. Can be suppressed. Moreover, since the brush holder 31 and the electromagnetic shielding member 61 are configured as an integrally molded product, an increase in the number of parts can be suppressed. Further, since the electromagnetic shield member 61 is embedded in the brush holder 31, the electromagnetic shield member 61 is stably held, and as a result, the electromagnetic shield member 61 can be prevented from falling off.

  8A and 8B, a part of the electromagnetic shield member 61 is embedded in the brush holder 31, but the entire electromagnetic shield member 61 is embedded in the brush holder 31. May be.

  For example, the configuration shown in FIGS. 9A and 9B may be changed. In the configuration shown in the figure, a conductive coating 62 as an electromagnetic shield portion is coated on the surface of the side edge portion 36a (flange portion 36) that enters the opening 49. The conductive film 62 is made of, for example, metal plating. As shown in FIG. 9B, the conductive film 62 is painted on the outer side surface of the side edge portion 36a in the Y direction, and is located in the opening 49 (in the recess 48). In addition, the conductive film 62 is formed on the surface of the convex portion 36b that contacts the first case 13 and the surface of the convex portion 36c that contacts the concave portion 48 of the second case 41 and the outer surface in the Y direction of the side edge portion 36a. Painted continuously. Thereby, the electrical connection between the conductive film 62 and the first and second cases 13 and 41 is ensured.

  According to such a configuration, at least a part of the opening 49 can be covered with the conductive film 62. Thereby, it can suppress that the electromagnetic noise produced by the sliding contact of the brush 32 and the commutator 24 is discharge | released outside from the opening part 49. FIG. Further, since the conductive film 62 is configured by being coated on the surface of the side edge portion 36a, it is possible to suppress electromagnetic noise emitted from the opening 49 while suppressing an increase in the number of components. In addition, by using the electroconductive film 62 as the electromagnetic shield part, it is possible to suppress the electromagnetic shield part from falling off due to vehicle vibration or the like as compared with the case where the electromagnetic shield part is the shield cap 51 as in the above embodiment. Can do.

  In the configuration in which the electromagnetic shield portion is the conductive film 62, the first case 13 and the second case 41 are assembled in such a manner that the brush holder 31 is interposed and fixed to each other with the screw 44, and then the conductive film 62. If it is made to paint, the electrical connection of the electroconductive film | membrane 62 and the 1st and 2nd cases 13 and 41 can be ensured easily.

  Moreover, you may use a conductive tape as an electromagnetic shielding part. In this case, the conductive tape as the electromagnetic shield portion is in a mode of closing the opening 49, with respect to the outer surface (radial outer surface) of the side edge portion 13e and the outer surface (radial outer surface) of the linear portion 47a. It is preferable to stick and fix. Furthermore, it is preferable that the conductive tape is a tape having an adhesive layer and is fixed to the outer surfaces of the side edge portion 13e and the linear portion 47a by the adhesive layer. In addition, the conductive tape should just be a thin plate-shaped member which has electroconductivity, For example, metal tapes, such as an aluminum tape, can be used. Moreover, it is good also as a structure which provided the electroconductive tape in the radial direction outer surface of the side edge part 36a of the flange part 36 (brush holder 31). According to the configuration using the conductive tape as the electromagnetic shield portion as described above, the conductive tape can be easily attached even after the first case 13, the second case 41, and the brush holder 31 are assembled. Therefore, it can contribute to the improvement of assembly.

  In the above embodiment, the shield cap 51 is in contact with each of the first and second cases 13 and 41. However, the shield cap 51 is not limited to this and only one of the first and second cases 13 and 41 is used. It is good also as a structure which contacts. In the configuration in which the first and second cases 13 and 41 are in contact (electrically connected) with each other as in the above embodiment, the shield cap 51 is in contact with only one of the first and second cases 13 and 41. Even in this configuration, the shield cap 51 is electrically connected to both the first and second cases 13 and 41.

  -The constituent material of the first case 13, the second case 41 and the electromagnetic shield part is not limited to metal, but has conductivity, such as conductive rubber, conductive resin, or metal-plated resin. If necessary, it can be changed as appropriate.

  In the above embodiment, the concave portion 48 constituting the opening 49 is formed only on the second case 41 side, but the concave portion 48 on the second case 41 side is omitted and the concave portion is formed only on the first case 13 side. Also good. Moreover, you may comprise an opening part in the recessed part formed in both the 1st and 2nd cases 13 and 41. FIG.

  In the above embodiment, the outer surface (radial outer surface) of the closing portion 52 of the shield cap 51 is the outer surface (radial direction) of the flange portion 13d (side edge portion 13e) and the outer peripheral wall 47 (linear portion 47a). Although it is assumed that it is assembled to be flush with the outer surface), it is not limited to this. For example, you may assemble | attach so that the outer surface of the obstruction | occlusion part 52 may become radial inside (the rotating shaft 21 side) from the outer surface of the side edge part 13e and the linear part 47a. Moreover, you may assemble | attach so that the outer surface of the obstruction | occlusion part 52 may become a radial direction outer side (counter-rotating shaft 21 side) from the outer surface of the side edge part 13e and the linear part 47a.

In the above embodiment, the shield cap 51 (blocking portion 52) may cover only a part of the opening 49.
In the above embodiment, the shield cap 51 that closes the opening 49 on the back surface 12a side of the second case 41 may be omitted. In the above embodiment, the connecting portion 45 on the back surface 12a side of the second case 41 is covered with the conductive vehicle body panel P. Therefore, even if the shield cap 51 on the back surface 12a side is omitted, the opening on the back surface 12a side. The electromagnetic noise emitted from 49 is suppressed by the vehicle body panel P.

  In the above embodiment, each convex portion 36b of each side edge portion 36a abuts on the side edge portion 13e of the flange portion 13d in the axial direction, and each convex portion 36c of each side edge portion 36a is a concave portion 48 of the second case 41. The flange portion 36 is sandwiched between the side edge portion 13e of the flange portion 13d and the bottom surface of the concave portion 48 of the second case 41 by contacting the bottom surface of the second case 41 in the axial direction, but is not limited thereto. For example, even if the flange portion 36 is sandwiched between the side edge portion 13e of the flange portion 13d and the bottom surface of the concave portion 48 of the second case 41 via the shield cap 51 (first and second sandwiched portions 53, 54). Good. More specifically, the first sandwiched portion 53 of the shield cap 51 is sandwiched between the convex portion 36b of the side edge portion 36a and the side edge portion 13e of the flange portion 13d, and the convex portion 36c and the second portion of the side edge portion 36a. A configuration in which the second sandwiched portion 54 of the shield cap 51 is sandwiched between the bottom surface of the concave portion 48 of the case 41 may be adopted. That is, each side edge part 36a (each convex part 36b, 36c) may be configured not to contact (is not directly clamped) the side edge part 13e of the flange part 13d and the bottom surface of the concave part 48 of the second case 41.

  In the above embodiment, the second case 41 is fixed to the vehicle body panel P by the plurality of screws Pa on the back surface 12a side in the Y direction. However, the present invention is not limited to this. For example, a bracket may be attached to the back surface 12a side of the second case 41 in the Y direction. In this case, the motor device 10 is fixed to the vehicle body panel P by mounting legs provided on the bracket and mounted on the vehicle.

  In the above embodiment, each side edge 36a includes three convex portions 36b and 36c that protrude in the axial direction from both axial end surfaces, but is not limited thereto, and may include four or more. . Moreover, you may provide the convex parts 36b and 36c one by two.

  Moreover, in the said embodiment, although the convex part 36b (convex part 36c) is provided one each in the center of the X direction of the side edge part 36a, and 1 each in the X direction both ends of the side edge part 36a, It is not limited to this. For example, the convex portion 36b (the convex portion 36c) may be provided so as to divide the side edge portion 36a into three equal parts in the X direction.

  In the above embodiment, each side edge 36a is formed with a pair of through holes 36d penetrating in the axial direction, but is not limited thereto. For example, one through hole 36d may be provided in each side edge 36a, or the through hole 36d may be omitted.

-The number of the brush 32 in the said embodiment is an illustration, and can be changed suitably.
In the above embodiment, the present invention is applied to the rear wiper motor. However, the present invention is not limited to this, and the present invention can also be applied to a motor device such as a windscreen wiping motor, a power window motor, or a power seat motor.

  -You may combine embodiment mentioned above and each modification suitably.

  DESCRIPTION OF SYMBOLS 10 ... Motor apparatus, 13 ... 1st case, 15 ... Armature (rotary body), 24 ... Commutator, 31 ... Brush holder, 32 ... Brush, 36a ... Side edge part (extension part), 41 ... 2nd case , 48 ... concave portion, 49 ... opening, 51 ... shield cap (electromagnetic shield part), 53 ... first clamped portion, 54 ... second clamped portion, 55 ... first locking claw, 56 ... second locking Claw, 61... Electromagnetic shield member (electromagnetic shield part), 62... Conductive film (electromagnetic shield part).

Claims (7)

A rotating body having a commutator;
A first case made of a conductive material and rotatably accommodating the rotating body;
A second case made of a conductive material and connected to the first case;
A brush holder made of a non-conductive material, at least partly held in the axial direction by the first case and the second case;
A brush held by the brush holder and in sliding contact with the commutator;
An opening is formed on the side surface of the connecting portion between the first case and the second case by forming a shape in which at least one of the first and second cases is recessed in the axial direction. A motor device in which a part of the brush holder is exposed to the outside,
A motor device comprising: a conductive electromagnetic shield portion that covers at least a part of the opening and is electrically connected to at least one of the first and second cases. The motor device according to claim 1,
The motor device according to claim 1, wherein the electromagnetic shield part is a shield cap mounted so as to cover at least a part of the opening. The motor device according to claim 2,
The motor device according to claim 1, wherein the shield cap includes a retaining claw for preventing the retaining cap to be locked to any one of the first case, the second case, and the brush holder. In the motor device according to claim 2 or 3,
The brush holder has an extending part that enters into the opening,
The shield cap includes a first sandwiched portion that is sandwiched between the extension portion and the first case in the axial direction, and a second sandwiched portion that is sandwiched between the extension portion and the second case in the axial direction. And a motor device. The motor device according to claim 1,
The brush holder and the electromagnetic shield part are configured as an integrally molded product,
At least a part of the electromagnetic shield part is embedded in the brush holder. The motor device according to claim 1,
The brush holder has an extending part that enters into the opening,
The motor device, wherein the electromagnetic shield part is a conductive coating film coated on the surface of the extension part. In the motor device according to any one of claims 1 to 6,
The outer surface of the electromagnetic shield part is positioned so as to be flush with the outer surface of the connecting portion of the first case and the second case, or the outer surface of the electromagnetic shield part is the first case and A motor device, wherein the motor device is located radially inward from an outer surface of a connecting portion of the second case.