JP2021013280A - motor - Google Patents

Abstract

To provide a motor that can suppress an increase in weight and the leakage of electromagnetic noise generated by a brush.SOLUTION: A motor unit 10 includes a conductive yoke housing 11, an armature 13 equipped with a commutator and arranged inside the yoke housing 11, and a brush 25 for feeding which is in sliding contact with the commutator. An output unit 30 includes a housing 31 in which the brush 25 is arranged inside, and outputs the rotation of the armature 13. The housing 31 includes an outer shell 41 on which the brush 25 is arranged, and an insulating portion 61 located inside the outer shell 41 and on the outer periphery of the brush 25. The outer shell 41 includes a resin portion 42 made of resin and a conductive portion 43 having conductivity. The insulating portion 61 is made of an insulating resin.SELECTED DRAWING: Figure 4

Description

The present disclosure relates to a motor.

In recent years, a large number of various electronic devices have been installed in vehicles. Therefore, it is desired to reduce the electromagnetic noise radiated from the motor in consideration of the influence on the electronic device. For example, the motor described in Patent Document 1 has a motor unit having a rotated armature and an output unit that outputs the rotation of the armature to the outside. The motor unit has a yoke housing in which the armature is arranged inside, and a brush for feeding power that is in sliding contact with the commutator of the armature. The output section has a housing in which the brush is located inside. Then, by making the housing made of metal, the housing suppresses the electromagnetic noise generated in the brush from leaking to the outside of the motor.

JP-A-2018-1221420

However, if the housing is made of metal, it is possible to suppress the electromagnetic noise generated in the brush from leaking to the outside of the motor, but there is a problem that the weight of the motor is increased due to the increase in the weight of the housing. .. Further, when the housing is made of metal, for example, a clearance may be provided between the inner surface of the housing and the parts in order to secure the insulation between the parts for supplying power to the armature such as a brush and the housing. .. Then, the housing becomes large, and as a result, the weight of the motor increases.

An object of the present disclosure is to provide a motor capable of suppressing an increase in weight and suppressing leakage of electromagnetic noise generated by a brush.

The motor of the present disclosure includes a conductive yoke housing (11), an armature (13) provided with a commutator (17) and arranged inside the yoke housing, and a power feeding brush (sliding contact with the commutator). A motor unit (10) having a 25) and an output unit (30, 30B) having a housing (31, 31A, 31B) in which the brush is arranged and outputting the rotation of the armature are provided. The housing has an outer shell portion (41, 41B) on which the brush is arranged inside, and an insulating portion (61, 61B) located inside the outer shell portion and located on the outer periphery of the brush. It has a resin portion (42, 42B) made of a resin and a conductive portion (43, 43B) having conductivity, and the insulating portion is made of an insulating resin.

According to the above aspect, the housing has an outer shell portion having a resin portion made of resin and an insulating portion made of an insulating resin. Therefore, the housing is lighter in weight than the housing made entirely of metal. Further, since the outer shell portion has a conductive portion having conductivity, the conductive portion can suppress the electromagnetic noise generated by the brush located inside the housing from leaking to the outside of the motor. From these facts, it is possible to suppress an increase in the weight of the motor and prevent electromagnetic noise generated by the brush from leaking to the outside of the motor.

The perspective view of the motor in one Embodiment. The schematic diagram of the motor in one Embodiment. The perspective view of the housing in one Embodiment. An exploded perspective view of the motor in one embodiment. An exploded perspective view of the housing in the modified example. Top view of the motor in the modified example.

Hereinafter, an embodiment of the motor will be described.
The motor 1 of the present embodiment shown in FIG. 1 is used, for example, as a drive source of a mechanism for adjusting the position of a seating portion in a front-rear direction in a power seat device mounted on a vehicle. The motor 1 has a motor unit 10 that generates a rotational force, and an output unit 30 that is connected to the motor unit 10 and outputs the rotational force generated by the motor unit 10.

[Composition of motor part]
As shown in FIGS. 1 and 2, the yoke housing 11 which is the outer shell of the motor portion 10 is made of a conductive metal material. The yoke housing 11 has a bottomed tubular shape. The yoke housing 11 has a flange portion 11a extending from an open end portion on the opposite side of the bottom portion of the yoke housing 11 to the outer peripheral side.

A permanent magnet 12 is fixed to the inner peripheral surface of the yoke housing 11. Further, inside the yoke housing 11, the armature 13 is arranged at a position inside the permanent magnet 12. The armature 13 is integrally rotatably fixed to the rotating shaft 14, the armature core 15 rotatably fixed to the rotating shaft 14, the coil 16 wound around the armature core 15, and the rotating shaft 14. It is equipped with a commutator 17. The base end portion of the rotating shaft 14 is pivotally supported by a bearing (not shown) provided in the center of the bottom portion of the yoke housing 11. Further, the tip portion of the rotating shaft 14 projects from the opening of the yoke housing 11 into the output portion 30. The commutator 17 is fixed to a portion of the rotating shaft 14 on the tip side of the rotating shaft 14 with respect to the armature core 15. In the present embodiment, the commutator 17 is located closer to the output unit 30 than the flange portion 11a. The coil 16 is electrically connected to the commutator 17.

A brush device 20 is arranged in the opening of the yoke housing 11. The brush device 20 has a brush holder 21 made of an insulating resin material. The brush holder 21 includes a brush holding portion 22 that substantially closes the opening of the yoke housing 11, a connector portion 23 located on the outer peripheral side of the flange portion 11a in a direction orthogonal to the axial direction X1 of the rotating shaft 14, and a brush holding portion. It has a connecting portion 24 that connects the portion 22 and the connector portion 23. The "axial direction X1 of the rotating shaft 14" is a direction parallel to the rotating axis L1 of the rotating shaft 14, and is hereinafter simply referred to as "axial direction X1".

The brush holding portion 22 has an outer shape that is one size smaller than the outer shape of the flange portion 11a when viewed from the axial direction X1. The rotating shaft 14 penetrates the brush holding portion 22 in the axial direction X1 and is pivotally supported by a bearing (not shown) held by the brush holding portion 22. The brush holding portion 22 holds a plurality of power feeding brushes 25 that are in sliding contact with the outer peripheral surface of the commutator 17. In the state where the brush device 20 is arranged in the opening of the yoke housing 11, the brush 25 held by the brush holding portion 22 is located closer to the tip end side of the rotating shaft 14 than the flange portion 11a in the axial direction X1.

As shown in FIG. 4, the brush device 20 has a plurality of terminals 26 formed of a conductive metal plate material. Each terminal 26 of the present embodiment is held by the brush holder 21 by embedding a part thereof in the brush holder 21 by insert molding. One end of each terminal 26 is exposed inside the connector 23. Further, the other end portion of the pair of terminals 26 for feeding power protrudes from the end portion of the brush holding portion 22 opposite to the yoke housing 11 in the axial direction X1 to the side opposite to the yoke housing 11. The other end portions of the pair of terminals 26 are located on both sides of the rotating shaft 14 when viewed from the axial direction X1. Further, the other end portions of the pair of terminals 26 are arranged apart from each other in a direction orthogonal to the protruding direction X2 of the connector portion 23 with respect to the brush holding portion 22 when viewed from the axial direction X1, and the brush holding portion. It is arranged along both ends in a direction orthogonal to the protruding direction X2 in 22. The protruding direction X2 of the connector portion 23 with respect to the brush holding portion 22 is a direction orthogonal to the axial direction X1. Hereinafter, the protruding direction X2 of the connector portion 23 with respect to the brush holding portion 22 will be simply referred to as “protruding direction X2”.

A corresponding brush 25 is electrically connected to the other end of the pair of power supply terminals 26 via a pigtail 27. The pigtail 27 is made of a flexible electric wire. One end of the pigtail 27 is electrically connected to the brush 25, and the other end is electrically connected to the power supply terminal 26. Each pigtail 27 is located closer to the tip of the rotating shaft 14 than the flange portion 11a in the axial direction X1.

The brush holder 21 has a pair of fixing claws 28 extending from the brush holding portion 22. FIG. 4 illustrates only one of the two fixed claws 28. The pair of fixed claws 28 extend from both ends of the brush holding portion 22 in the direction orthogonal to the protruding direction X2 to the tip end side of the rotating shaft 14, that is, the output portion 30 side along the axial direction X1 when viewed from the axial direction X1. ing. Each fixing claw 28 has a fixing hole 28a penetrating in a direction orthogonal to both the axial direction X1 and the protruding direction X2. The fixed claw 28 is elastically deformable so that the tip end portion of the fixed claw 28 is displaced with respect to the base end portion of the fixed claw 28 in a direction orthogonal to both the axial direction X1 and the protruding direction X2.

[Output section configuration]
As shown in FIGS. 2 and 4, the output unit 30 has a housing 31 in which the brush 25 is arranged inside, and outputs the rotation of the armature 13. The tip of the rotating shaft 14 is arranged inside the housing 31. Further, the output unit 30 has a connecting member 32 that is housed in the housing 31 and is integrally rotatably provided at the tip of the rotating shaft 14.

As shown in FIGS. 2 to 4, the housing 31 has an outer shell portion 41 in which the brush 25 is arranged inside, and an insulating portion 61 located inside the outer shell portion 41 and on the outer periphery of the brush 25. In FIGS. 3 and 4, dots are added to the insulating portion 61 to facilitate understanding.

The outer shell 41 constitutes the outer shell of the output unit 30. The outer shell portion 41 has a resin portion 42 made of resin and a conductive portion 43 having conductivity.
The resin portion 42 is made of a resin that can be metal-plated. In the present embodiment, the resin portion 42 is made of an insulating resin. The resin portion 42 is made of, for example, polypropylene. The resin portion 42 has a bottomed tubular shape that opens toward the yoke housing 11.

The resin portion 42 has a side wall 44 having a substantially square tubular shape extending in the axial direction X1, and a bottom portion 45 integrally provided at an end portion of the side wall 44 opposite to the yoke housing 11. An output hole 46 that penetrates the bottom portion 45 in the axial direction X1 is provided in the central portion of the bottom portion 45.

The side wall 44 has four integrally provided wall portions 44a, 44b, 44c, 44d. In the present embodiment, of the wall portions 44a to 44d, the wall portion adjacent to the connector portion 23 is referred to as the wall portion 44a. Further, the wall portion located on the opposite side of the brush holding portion 22 with respect to the wall portion 44a is referred to as the wall portion 44b. Further, the two wall portions located on both sides of the brush device 20 between the wall portion 44a and the wall portion 44b are referred to as wall portions 44c and 44d.

The wall portion 44a is provided with a through recess 47 through which the connecting portion 24 of the brush holder 21 penetrates. The penetrating recess 47 is recessed from the end of the wall portion 44a opposite to the bottom portion 45 toward the bottom portion 45 side, and penetrates the wall portion 44a in the thickness direction of the wall portion 44a. The thickness direction of the wall portion 44a is a direction parallel to the projecting direction X2 when viewed from the axial direction X1.

The resin portion 42 has a plurality of ground contact convex portions 48. In the present embodiment, the resin portion 42 has four ground contact convex portions 48. There is one grounding convex portion 48 at the end of the wall portions 44c and 44d opposite to the bottom portion 45, and one at the end portion of the corner portion between the wall portions 44b and the wall portion 44c opposite to the bottom portion 45. One is provided at the end opposite to the bottom 45 at the corner of the portion 44b and the wall portion 44d. Each grounding convex portion 48 extends in the axial direction X1 from an end portion of the side wall 44 opposite to the bottom portion 45. In the present embodiment, the ground contact surface 49, which is the tip surface of each ground contact convex portion 48, has a planar shape orthogonal to the axial direction X1.

Further, the resin portion 42 has a fixed convex portion 51 on the outer peripheral surface of the resin portion 42. The fixed convex portion 51 is for locking the fixed claw 28. In the present embodiment, one is provided on the outer surface of the wall portion 44c and one on the outer surface of the wall portion 44d. Each fixed convex portion 51 projects from the outer surface of the wall portions 44c and 44d to the outer peripheral side of the housing 31.

The conductive portion 43 is a metal film made of a conductive metal. The conductive portion 43 imparts conductivity to the resin portion 42. In the present embodiment, the conductive portion 43 covers the entire outer surface of the resin portion 42. As the material of the conductive portion 43, for example, an alloy of copper and tin is used. The conductive portion 43 is formed by subjecting the outer surface of the resin portion 42 to metal plating.

The conductive portion 43 has a grounding portion 43a that covers each grounding surface 49 of the resin portion 42. The grounding portion 43a is provided continuously with the portion of the conductive portion 43 that covers the outer peripheral surface of the side wall 44. Further, the ground contact portion 43a covers the entire ground contact surface 49. The ground contact portion 43a has a flat shape along the ground contact surface 49 which is a flat surface orthogonal to the axial direction X1.

The housing 31 is fixed to the motor portion 10 in a state where a portion of the brush holding portion 22 located outside the yoke housing 11 with respect to the flange portion 11a is housed inside the outer shell portion 41. Specifically, the housing 31 is fixed to the brush holder 21 by fitting the fixing protrusions 51 into the fixing holes 28a of the two fixing claws 28, respectively.

In the state where the housing 31 is fixed to the brush holder 21, the brush 25 held by the brush holding portion 22 is arranged inside the outer shell portion 41. Further, in the same state, the connecting portion 24 of the brush holder 21 is inserted into the through recess 47 from the axial direction X1. Further, the connecting member 32 is exposed to the outside of the housing 31 from the output hole 46. Then, the connecting member 32 can be connected to a drive mechanism (not shown) for moving the seating portion of the seat in the front-rear direction of the vehicle. Further, in the same state, the ground contact portion 43a comes into contact with the flange portion 11a from the axial direction X1. Therefore, the conductive portion 43 is grounded to the yoke housing 11 at the grounding portion 43a.

The insulating portion 61 is provided inside the resin portion 42. The insulating portion 61 is made of a resin in which a metal film is not formed on the surface of the insulating portion 61. In the present embodiment, the insulating portion 61 is made of an insulating resin that is not metal-plated. The insulating portion 61 is made of, for example, polycarbonate. Further, in the present embodiment, the resin portion 42 and the insulating portion 61 are integrally molded products. The resin portion 42 and the insulating portion 61 are integrally formed by two-color molding. In FIG. 4, the resin portion 42 and the insulating portion 61, which are integrally molded products, are shown in an exploded manner.

The insulating portion 61 is located between the brush 25 and the resin portion 42. Further, the insulating portion 61 is provided on the inner peripheral surface of the housing 31 in a portion that serves as a current path to the brush 25, that is, a portion close to the pigtail 27 and the terminal 26. Therefore, in the present embodiment, the insulating portion 61 is formed on the inner side surfaces of the wall portions 44c and 44d on both sides in the direction orthogonal to the projecting direction X2 when viewed from the axial direction X1 and the wall portions 44b on the opposite side to the connector portion 23. It is provided on the inner surface. The insulating portion 61 covers the entire inner side surface of the wall portions 44c and 44d. Further, the insulating portion 61 covers a portion of the inner surface of the wall portion 44b except for the vicinity of the end portion on the side opposite to the bottom portion 45. Further, the portions of the insulating portion 61 that cover the inner surfaces of the wall portions 44c and 44d are connected by the portions of the insulating portion 61 that cover the inner surfaces of the wall portions 44b. Therefore, the insulating portion 61 has a rectangular shape that opens toward the connector portion 23 in the shape seen from the axial direction X1.

In the insulating portion 61, the portions covering the inner surfaces of the wall portions 44c and 44d face each other in close proximity to the terminal 26 exposed from the brush holder 21. Further, in the insulating portion 61, the portion covering the vicinity of the corner portion between the wall portion 44c and the wall portion 44b and the portion covering the vicinity of the corner portion between the wall portion 44d and the wall portion 44b face each other in close proximity to the pigtail 27. .. In the motor 1 of the present embodiment, the wall portion 44a adjacent to the connector portion 23 is up to the brush 25 when the housing 31 is assembled to the motor portion 10 or when the housing 31 is fixed to the motor portion 10. It is unlikely that the component that will be the current path will come into contact with the inner surface.

Further, in the housing 31 of the present embodiment, an adjusting recess 52 is provided in a portion of the resin portion 42 in which the insulating portion 61 is formed on the inner side surface. Therefore, the portion of the side wall 44 of the resin portion 42 in which the insulating portion 61 is formed on the inner peripheral surface is slightly thinner than the portion in which the insulating portion 61 is not formed. As a result, the increase in size of the housing 31 due to the provision of the insulating portion 61 is suppressed. Further, the thickness of the insulating portion 61 can be adjusted while suppressing the thickness of the housing 31 from increasing. Incidentally, the housing 31 of the present embodiment has a thickness similar to that when the housing is formed of, for example, one kind of resin.

Here, a method of manufacturing the housing 31 will be described.
First, a molding mold cavity (not shown) is filled with an insulating resin that cannot be plated with metal, and then the resin is solidified to form an insulating portion 61. After that, the insulating portion 61 is arranged in another molding cavity (not shown). Then, after the cavity for forming the resin portion 42 is filled in the cavity of the other molding mold, the resin portion 42 is formed by solidifying the resin. As a result, an integrally molded product of the insulating portion 61 and the resin portion 42 is formed.

After that, the integrally molded product of the insulating portion 61 and the resin portion 42 is metal-plated to form the conductive portion 43. For example, the integrally molded product of the insulating portion 61 and the resin portion 42 is immersed in the plating solution stored in the plating tank to form the conductive portion 43 which is a metal film covering the entire outer surface of the resin portion 42. Will be done. At this time, since the insulating portion 61 is made of a resin to which metal plating is not applied, no metal film is formed on the surface of the insulating portion 61. Then, the housing 31 is completed by forming the conductive portion 43.

The operation of this embodiment will be described.
In the motor 1 configured as described above, by connecting an external connector (not shown) to the connector portion 23, power can be supplied to the motor 1 from an external power supply device. Then, the current supplied through the external connector is supplied to the armature 13 via the terminal 26, the pigtail 27, and the brush 25. Then, the armature 13 rotates. The rotation of the armature 13, that is, the rotation of the rotating shaft 14, is output to the outside from the connecting member 32 that rotates integrally with the rotating shaft 14.

In the brush 25 that is in sliding contact with the commutator 17 as the armature 13 rotates, the electromagnetic noise generated in the sliding contact portion with the commutator 17 is caused by the conductive portion 43 of the housing 31 located on the outer periphery of the brush 25 to cause the motor 1. Leakage to the outside is suppressed.

The effect of this embodiment will be described.
(1) The housing 31 has an outer shell portion 41 having a resin portion 42 made of resin, and an insulating portion 61 made of an insulating resin. Therefore, the housing 31 is lighter in weight than the housing made entirely of metal. Further, since the outer shell portion 41 has the conductive portion 43 having conductivity, the conductive portion 43 can suppress the electromagnetic noise generated by the brush 25 located inside the housing 31 from leaking to the outside of the motor 1. From these facts, it is possible to suppress an increase in the weight of the motor 1 and prevent electromagnetic noise generated by the brush 25 from leaking to the outside of the motor 1.

(2) The resin portion 42 and the insulating portion 61 are integrally molded products. Therefore, the housing 31 can be easily manufactured.
(3) Generally, in order to give a resin housing a shielding function, it is conceivable to form a conductive metal film on the surface of the housing. In this case, it is necessary to insulate the component that becomes the current path to the brush and the metal film formed on the housing.

For example, after forming a metal film on the entire surface of the housing, it is conceivable to further insulate the inner surface of the housing to insulate the metal film from the component that becomes the current path to the brush. By the way, when assembling the housing and the motor portion, the inner surface of the housing may be damaged because the parts arranged inside the housing come into contact with the inner surface of the housing. Then, the metal film may be exposed by damaging the insulated portion on the inner surface of the housing. Therefore, in order to improve the insulation between the component that becomes the current path to the brush and the housing, for example, the clearance between the component that becomes the current path to the brush and the inner surface of the housing is increased. Then, the housing becomes large, and as a result, the motor becomes large.

Further, for example, before forming a metal film on the surface of the housing, masking is applied to the inner surface of the housing to prevent the metal film from being formed at a desired portion, so that the component and the housing that become the current path to the brush can be separated. Insulation is conceivable. However, it is often difficult to mask the housing because it has a complicated shape with irregularities or a fine shape. Therefore, there arises a problem that the man-hours for manufacturing the motor increase and the manufacturing cost of the motor increases.

On the other hand, in the housing 31 of the present embodiment, the conductive portion 43 is a metal film that covers the outer surface of the resin portion 42. Further, the insulating portion 61 is made of a resin in which a metal film is not formed on the surface of the insulating portion 61. Therefore, even if the conductive portion 43 is formed on the surface of the resin portion 42 in a state where the resin portion 42 and the insulating portion 61 are integrated, the conductive portion 43 which is a metal film is not formed on the surface of the insulating portion 61. Therefore, since it is not necessary to perform the step of masking the inner surface of the housing before forming the metal film, it is possible to suppress an increase in man-hours for manufacturing the motor 1 and an increase in the manufacturing cost of the motor 1. At the same time, the conductive portion 43, which is a metal film, can be provided on the resin housing 31. That is, the housing 31 having the conductive portion 43 which is a metal film can be easily formed. Further, when the housing 31 and the motor portion 10 are assembled, even if the parts arranged inside the housing 31 come into contact with the inner surface of the housing 31, the exposure of the conductive portion 43 to the inside of the housing 31 is suppressed. .. Therefore, in order to improve the insulation between the component that becomes the current path to the brush 25 and the housing 31, it is not necessary to increase the clearance between the component that becomes the current path to the brush 25 and the inner surface of the housing 31. Therefore, the increase in size of the housing 31 is suppressed. As a result, even in the motor 1 provided with the housing 31 having the conductive portion 43 which is a metal film, the insulation between the housing 31 and the brush 25 can be ensured without increasing the size of the motor 1.

(4) The conductive portion 43 has a grounding portion 43a that abuts on the yoke housing 11. Therefore, when the grounding portion 43a comes into contact with the yoke housing 11, the conductive portion 43 is grounded to the yoke housing 11. Therefore, it is possible to better suppress the electromagnetic noise generated by the brush 25 from leaking to the outside of the motor 1 in the conductive portion 43.

(5) The conductive portion 43 covers the entire outer surface of the resin portion 42. Therefore, it becomes more difficult for the electromagnetic noise generated by the brush 25 to pass through the outer shell portion 41. Therefore, it is possible to further suppress the electromagnetic noise generated by the brush 25 from leaking to the outside of the motor 1.

(6) The housing 31 including the outer shell portion 41 and the insulating portion 61 can be formed in the same shape as the resin housing provided in the existing motor. Therefore, in the existing motor, the existing housing and the housing 31 formed in the same shape as the existing housing can be simply replaced. In this way, it is not necessary to change the assembly method or the like on the production line. Therefore, it is possible to suppress an increase in the manufacturing cost of the motor 1 due to the housing 31 having the conductive portion 43 and the insulating portion 61.

This embodiment can be modified and implemented as follows. The present embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.
-In the above embodiment, the conductive portion 43 covers the entire outer surface of the resin portion 42. However, the conductive portion 43 does not necessarily have to cover the entire outer surface of the resin portion 42, and may cover at least a part of the outer surface of the resin portion 42. For example, the conductive portion 43 does not necessarily have to be provided on the outer surface of the bottom portion 45. Further, for example, the conductive portion 43 may be provided only on the outer surface of at least one of the wall portions 44a to 44d. Further, the conductive portion 43 may cover at least a part of the outer surface of the resin portion 42 and a portion of the inner surface of the resin portion 42 that is not covered by the insulating portion 61.

Further, the conductive portion 43 may have a hole in which the outer surface of the resin portion 42 is partially exposed. For example, the conductive portion 43 may have a plurality of circular holes arranged regularly or irregularly. Further, for example, the conductive portion 43 may be provided in a grid pattern on at least a part of the outer surface of the resin portion 42.

In the above embodiment, the ground contact surface 49 of the housing 31 has a planar shape orthogonal to the axial direction X1, so that the ground contact portion 43a of the conductive portion 43 has a flat shape along the ground contact surface 49. However, the shapes of the ground contact surface 49 and the ground contact portion 43a are not limited to this. The ground contact surface 49 and the ground contact portion 43a may have a shape in which the ground contact portion 43a contacts the yoke housing 11 when the housing 31 is assembled to the motor portion 10. For example, the ground plane 49 may be spherical. The ground contact portion 43a may have a spherical shape along the spherical ground surface 49.

Further, the number of the grounding portions 43a included in the conductive portion 43 is not limited to four, and may be three or less, or five or more. Further, the conductive portion 43 does not necessarily have to include the grounding portion 43a.

In the above embodiment, after the insulating portion 61 is formed, the resin portion 42 integrally molded with the insulating portion 61 is formed. However, after forming the resin portion 42, the insulating portion 61 integrally molded with the resin portion 42 may be formed.

The range in which the insulating portion 61 is provided in the housing 31 is not limited to the range of the above embodiment. The insulating portion 61 may be located inside the outer shell portion 41 and on the outer circumference of the brush 25. Therefore, for example, the insulating portion 61 may be formed inside the wall portion 44a in addition to the inner side surface of the wall portions 44b, 44c, 44d.

-In the above embodiment, the resin portion 42 and the insulating portion 61 are integrally molded products, but they do not necessarily have to be integrally molded products.
For example, the housing 31A shown in FIG. 5 has a resin portion 42 and an insulating portion 61 formed separately. The insulating portion 61 is assembled inside the resin portion 42. The conductive portion 43 is formed on the outer surface of the resin portion 42 after the insulating portion 61 is assembled inside the resin portion 42.

-In the above embodiment, the resin portion 42 is made of polypropylene. However, the material of the resin portion 42 is not limited to this. For example, the resin portion 42 may be made of ABS resin.

-In the above embodiment, the insulating portion 61 is made of polycarbonate. However, the material of the insulating portion 61 is not limited to this, and may be any insulating resin in which a metal film is not formed on the surface.
-In the above embodiment, the conductive portion 43 is made of an alloy of copper and tin. However, the material of the conductive portion 43 is not limited to this. The conductive portion 43 may be any conductive material that can coat the outer surface of the resin portion 42, that is, a conductive material that can be fixed to the outer surface of the resin portion 42 in a film form. For example, the conductive portion 43 may be made of an alloy of a metal other than tin and copper. Further, for example, the conductive portion 43 may be made of copper. Further, the conductive portion 43 may be made of a conductive resin such as a conductive elastomer.

-In the above embodiment, the conductive portion 43, which is a metal film, is formed by plating. However, the method for forming the conductive portion 43 is not limited to this. For example, the conductive portion 43 may be formed by applying a conductive metal to the outer surface of the resin portion 42. Examples of the coating method include brush coating, spray coating, dip coating and the like.

In the above embodiment, the housing 31 has an outer shell portion 41 having a resin portion 42 and a conductive portion 43 covering the outer surface of the resin portion 42, and an insulating portion 61 provided inside the outer shell portion 41. .. However, the housing 31 may have an outer shell made of a conductive resin and an insulating portion 61 provided inside the outer shell. In this case, the outer portion made of the conductive resin serves as both the resin portion made of the resin and the conductive portion having conductivity. In this way, it is not necessary to form the resin portion and the conductive portion, respectively, so that the housing 31 can be easily manufactured. The outer shell portion made of the conductive resin and the insulating portion 61 may be integrally molded products, or may be formed and assembled separately.

The configuration of the output unit 30 is not limited to the configuration of the above embodiment. That is, the shape of the housing 31 and the parts housed in the housing 31 are not limited to those of the above embodiment.
For example, the motor 1B shown in FIG. 6 includes a motor unit 10 and an output unit 30B. The output unit 30B has a housing 31B and a speed reduction mechanism 71 housed in the housing 31B. In FIG. 6, the same components as those in the above embodiment or the corresponding configurations are designated by the same reference numerals.

The housing 31B is fixed to the flange portion 11a by the screw 81 in a state of accommodating a portion of the brush holding portion 22 that protrudes outward from the flange portion 11a of the yoke housing 11. The brush 25 is arranged inside the housing 31B. Further, the tip end portion of the rotating shaft 14 projects into the housing 31B.

The speed reduction mechanism 71 has a worm shaft 72 arranged coaxially with the rotating shaft 14, and a worm wheel 73 that meshes with the worm shaft 72. The worm shaft 72 is connected to the rotating shaft 14 via a connecting member 82 such as a clutch arranged in the housing 31B. At the center of the shaft of the worm wheel 73, an output shaft 74 that rotates integrally with the worm wheel 73 is provided. The tip of the output shaft 74 projects to the outside of the housing 31B. In FIG. 6, the tip of the output shaft 74 is located on the back side of the paper surface. Then, the rotation transmitted from the rotating shaft 14 to the worm shaft 72 via the connecting member 82 as the motor unit 10 is driven is decelerated by the worm shaft 72 and the worm wheel 73 and output from the output shaft 74. In the example shown in FIG. 6, the reduction mechanism 71 is composed of the worm shaft 72 and the worm wheel 73, but may be further provided with a reduction gear to which the rotation of the worm wheel 73 is transmitted. In this case, the output shaft 74 is provided so as to be integrally rotatable with the reduction gear in the final stage.

The housing 31B has an outer shell portion 41B on which the brush 25 is arranged inside, and an insulating portion 61B located inside the outer shell portion 41B and on the outer periphery of the brush 25.
The outer shell portion 41B has a resin portion 42 made of resin and a conductive portion 43B having conductivity. The resin portion 42B has a shape capable of accommodating the tip portion of the rotating shaft 14, the portion of the brush holding portion 22 located outside the yoke housing 11 from the flange portion 11a, and the speed reduction mechanism 71. The resin portion 42B is made of the same material as the resin portion 42 of the above embodiment. The conductive portion 43B covers the entire outer surface of the resin portion 42. The conductive portion 43B is made of the same material as the conductive portion 43 of the above embodiment.

The insulating portion 61B is provided inside the resin portion 42B. In FIG. 6, the insulating portion 61 is illustrated by a chain double-dashed line. The insulating portion 61B is made of the same material as the insulating portion 61 of the above embodiment. The insulating portion 61B is interposed inside the resin portion 42 with the brush holding portion 22. Further, the insulating portion 61B is provided on the inner surface of the resin portion 42 at a portion located on the outer periphery of the brush holding portion 22. That is, the insulating portion 61B is provided on the inner surface of the housing 31B in a portion close to a part such as a pigtail and a terminal that serves as a current path to the brush 25.

Even in such a motor 1B, the same effect as that of the above embodiment can be obtained. Further, the conductive portion 43B can suppress the electromagnetic noise radiated from the worm shaft 72 from leaking to the outside of the motor 1B.

-The motor 1 may be used as a drive source for a device other than the power seat device mounted on the vehicle. For example, the motor 1 may be used as a drive source for a power window device that electrically raises and lowers the window glass of a vehicle. Further, for example, the motor 1 may be used as a drive source of a sunroof device that electrically operates an opening / closing body for opening / closing an opening provided in a ceiling portion of a vehicle.

The technical idea that can be grasped from the above-described embodiment and modified example will be described.
(A) The motor according to claim 3, wherein the conductive portion covers the entire outer surface of the resin portion, or a motor according to claim 3.

1,1B ... motor, 10 ... motor unit, 11 ... yoke housing, 13 ... armature, 17 ... commutator, 25 ... brush, 30, 30B ... output unit, 31,31A, 31B ... housing, 41,41B ... outer shell Parts, 42, 42B ... Resin part, 43, 43B ... Conductive part, 43a ... Grounding part, 61, 61B ... Insulating part.

Claims (4)

A motor having a conductive yoke housing (11), an armature (13) provided with a commutator (17) and arranged inside the yoke housing, and a power feeding brush (25) that is in sliding contact with the commutator. Part (10) and
It has a housing (31, 31A, 31B) in which the brush is arranged, and has an output unit (30, 30B) that outputs the rotation of the armature.
The housing has an outer shell portion (41, 41B) on which the brush is arranged inside, and an insulating portion (61, 61B) located inside the outer shell portion and located on the outer periphery of the brush.
The outer shell portion has a resin portion (42, 42B) made of resin and a conductive portion (43, 43B) having conductivity.
The insulating portion is a motor made of an insulating resin. The motor according to claim 1, wherein the resin portion and the insulating portion are integrally molded products. The conductive portion is a metal film that covers at least a part of the outer surface of the resin portion.
The motor according to claim 1 or 2, wherein the insulating portion is made of a resin in which the metal film is not formed on the surface of the insulating portion. The motor according to any one of claims 1 to 3, wherein the conductive portion has a ground contact portion (43a) that abuts on the yoke housing.