WO2015040823A1

WO2015040823A1 - Brush-equipped motor

Info

Publication number: WO2015040823A1
Application number: PCT/JP2014/004638
Authority: WO
Inventors: 豪坂田; 雄一郎定永
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2013-09-17
Filing date: 2014-09-10
Publication date: 2015-03-26
Also published as: JP2016197930A; CN204669170U

Abstract

A brush-equipped motor (100) is provided with a rotor (8), a pair of bearings (4A, 4B), a brush holder (1), a brush (6), a brush spring (7) that is an elastic member, and a holding section (1A). The holding section (1A) comprises anti-dust plates (10, 10A) and a dust-collecting section (11). The anti-dust plates (10, 10A) face a commutator (5) between a pair of the brush holders (1). The anti-dust plates (10, 10A) are positioned along the axial center (3B) direction of a shaft (3). The dust-collecting section (11) accumulates brush wear powder via the anti-dust plates (10, 10A), said brush wear powder being generated when the brush (6) and the commutator (5) slide.

Description

Motor with brush

The present invention particularly relates to a brushed motor useful for automobile electrical components, industrial equipment, and the like, which involves difficulty in motor replacement work and motor maintenance work.

Conventionally, a motor with a brush has been widely used as a power source for various products because it has a large starting torque and is inexpensive. Patent Document 1 discloses the structure of this type of brushed motor.

As shown in FIG. 18, the motor with brush includes a shaft 3, a pair of

bearings

4C and 4D, a commutator 5, a brush 6, a frame 2, a core 14, a winding 15, a magnet 9, Is provided.

The pair of

bearings

4C and 4D support the shaft 3. The commutator 5 is attached to the outer peripheral surface of the shaft 3. The brush 6 contacts the commutator 5 while sliding. The frame 2 holds the brush 6. The core 14 is attached to the outer peripheral surface of the shaft 3. The winding 15 is wound around the core 14. The magnet 9 is a stator and is disposed outside the core 14.

Furthermore, the motor with brush disclosed in Patent Document 1 has a pocket 111. In the motor with brush, when the shaft 3 rotates, the commutator 5 rotates with the shaft 3. At this time, the brush 6 and the commutator 5 are in sliding contact with each other on a sliding surface in contact with each other. When the brush 6 and the commutator 5 are in sliding contact with each other, brush wear powder is generated from the brush 6 on the sliding surface. The generated brush wear powder is stored in the pocket 111.

The brush motor suppresses the brush wear powder from being diffused into the brush motor by collecting the brush wear powder in the pocket 111 through the rib 110. Therefore, the motor with a brush has prevented the insulation resistance value from significantly decreasing in each member located inside the motor with a brush.

Japanese Utility Model Publication No. 58-22865

A motor with a brush targeted by the present invention includes a rotor, a pair of bearings, a brush holder, a brush, a brush spring that is an elastic member, and a holding portion.

The rotor has a shaft and a commutator located on the outer peripheral surface of the shaft. The rotor rotates around the shaft center.

¡A pair of bearings support the shaft rotatably.

The brush holder forms a pair of positive and negative electrodes and has an opening at a position facing the commutator. The brush holder is positioned to face the commutator along the radial direction of the shaft orthogonal to the axis.

The brush is located in the brush holder of each positive and negative electrode, and can move along the radial direction of the shaft. The brush slides in contact with the commutator on the sliding surface through the opening.

The elastic member is positioned so as to press the brush against the commutator in each of the positive and negative brush holders.

¡The holding part holds the brush holder. In particular, the holding part has a dustproof plate and a dust collecting part. The dustproof plate faces the commutator between the pair of brush holders. The dustproof plate is located along the axial direction of the shaft.

The dust collector accumulates brush wear powder generated when the brush and commutator slide through the dust-proof plate.

FIG. 1 is a cross-sectional view of a brushed motor according to Embodiment 1 of the present invention. FIG. 2 is a perspective view showing an outline of a brush holder used in the motor with brushes according to Embodiment 1 of the present invention. FIG. 3 is an enlarged schematic view of a main part of the brush holder shown in FIG. FIG. 4 is an enlarged schematic view of another main part of the brush holder shown in FIG. FIG. 5 is a cross-sectional view of a brushed motor according to Embodiment 2 of the present invention. FIG. 6 is a perspective view showing an outline of a brush holder used in the motor with brushes in the second embodiment of the present invention. FIG. 7 is an enlarged schematic view of a main part of the brush holder shown in FIG. FIG. 8 is an enlarged schematic view of another main part of the brush holder shown in FIG. FIG. 9 is an enlarged schematic view of still another main part of the brush holder shown in FIG. FIG. 10 is an essential part enlarged view showing a specific example 1 of the fin used in the motor with brush in the second embodiment. FIG. 11 is an essential part enlarged view showing a specific example 2 of the fins used in the motor with brushes in the second embodiment. FIG. 12 is an essential part enlarged view showing a specific example 3 of the fins used in the brushed motor according to the second embodiment. FIG. 13 is an essential part enlarged view showing a specific example 4 of the fin used in the motor with brush in the second embodiment. FIG. 14 is an essential part enlarged view showing a specific example 5 of fins used in the motor with brush in the second embodiment. FIG. 15 is an essential part enlarged view showing a specific example 6 of the fin used in the motor with brush in the second embodiment. FIG. 16 is an essential part enlarged view showing a specific example 7 of the fin used in the motor with brush in the second embodiment. FIG. 17 is an essential part enlarged view showing a specific example 8 of the fin used in the motor with brush in the second embodiment. FIG. 18 is a cross-sectional view of a conventional brushed motor.

The brushed motor according to the embodiment of the present invention can accumulate brush wear powder generated by driving the brushed motor in a predetermined place by the configuration described later. Therefore, the brushed motor in the present embodiment can prevent the brush wear powder from diffusing inside the brushed motor. As a result, the brushed motor in the present embodiment can suppress a decrease in the insulation resistance value in an unspecified part in the brushed motor.

In other words, the conventional brushed motor had the following points to be improved. That is, in the conventional motor with a brush, brush wear powder is generated due to the influence of the rotating speed of the rotor. The generated brush wear powder was diffused from the gap between the brush and the pocket into the brushed motor. The brush abrasion powder accumulated in the unspecified part inside the motor with the brush significantly reduced the insulation resistance value of the unspecified part.

In addition, products incorporating brush motors may be used in harsh environments such as severe vibrations. Under such circumstances, the brush wear powder once in the pocket may be diffused again into the brushed motor due to external factors such as vibration.

Therefore, the brush motor in the embodiment of the present invention is provided with a dustproof plate positioned in the direction in which the commutator rotates with respect to the sliding surface where the brush and the commutator contact. In particular, the dustproof plate is preferably provided to face the commutator so that the gap between the commutator and the dustproof plate is narrowed.

If this configuration is used, it is possible to prevent the brush wear powder generated by the sliding contact between the brush and the commutator from spreading into the motor with the brush.

If the brush wear powder can be prevented from diffusing into the brushed motor, it is possible to suppress the phenomenon that the insulation resistance value decreases in an unspecified part in the brushed motor. In other words, the brushed motor in the present embodiment can maintain the insulation resistance value inside the brushed motor at a high value for a long period of time.

Furthermore, the brushed motor according to the present embodiment has a dust collecting portion at a position in consideration of the use state of a product in which the brushed motor is incorporated. Specifically, the dust collecting part is provided at a position where the brush wear powder is accumulated by the action of gravity.

本 With this configuration, brush wear powder that has leaked into the brushed motor is naturally collected in the dust collector.

Particularly, a plurality of fins may be formed at the bottom of the dust collecting part. Each fin is formed of a flat plate.

¡With this configuration, brush wear powder collected between adjacent fins will not diffuse again.

That is, with the above-described configuration, the brushed motor in the present embodiment can prevent the brush wear powder once accumulated in the dust collecting portion from diffusing into the brushed motor again.

Therefore, even if the product incorporating the brushed motor in this embodiment is used in a severe environment such as severe vibration, the insulation resistance value inside the brushed motor is maintained at a high value for a long period of time. it can.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following embodiments are examples embodying the present invention, and do not limit the technical scope of the present invention.

(Embodiment 1)
FIG. 1 is a cross-sectional view of a brushed motor according to Embodiment 1 of the present invention. FIG. 2 is a perspective view showing an outline of a brush holder used in the motor with brushes according to Embodiment 1 of the present invention.

As shown in FIG. 1, the brushed motor 100 according to the first embodiment includes a rotor 8, a pair of

bearings

4A and 4B, a brush holder 1, a brush 6, a brush spring 7 that is an elastic member, and a holding member. 1A.

The rotor 8 has a shaft 3 and a commutator 5 located on the outer peripheral surface 3 A of the shaft 3. The rotor 8 rotates about the axis 3B of the shaft 3 as the center of rotation.

The pair of

bearings

4A and 4B support the shaft 3 in a rotatable manner.

1 and 2, the brush holder 1 forms a pair of positive and negative electrodes and has an opening 1B at a position facing the commutator 5. The brush holder 1 is positioned facing the commutator 5 along the radial direction of the shaft 3 orthogonal to the axis 3B.

The brush 6 is located in the brush holder 1 of each of the positive and negative electrodes, and is movable along the radial direction of the shaft 3. The brush 6 slides in contact with the commutator 5 on the sliding surface 17 through the opening 1B.

As shown in FIG. 1, the brush spring 7 which is an elastic member is positioned so as to press the brush 6 against the commutator 5 in the brush holder 1 of each of the positive and negative electrodes.

The holding unit 1A holds the brush holder 1. In particular, the holding unit 1 A includes dust-

proof plates

10 and 10 A and a dust collecting unit 11.

1 and 2, the

dustproof plates

10 and 10A face the commutator 5 between the pair of brush holders 1. The

dustproof plates

10 and 10 A are located along the direction of the axis 3 B of the shaft 3.

The dust collecting unit 11 accumulates brush wear powder generated when the brush 6 and the commutator 5 slide through the

dustproof plates

10 and 10A.

As shown in FIG. 2, in particular, the dustproof plate 10 is positioned opposite to the outer peripheral surface 5 A of the commutator 5 in the circumferential direction centering on the shaft center 3 B on a cross section orthogonal to the shaft center 3 B. Further, the dustproof plate 10 is at least in the gravity direction with respect to the commutator 5. Note that the direction of gravity is a direction determined in a state where a motor with a brush is used.

Alternatively, the dust-proof plate 10 may be positioned on the downstream side at least in the direction 20 in which the commutator 5 rotates.

Further, the dustproof plate 10A is formed so as to guide the brush wear powder to the dust collecting portion 11.

Further, the brush holder 1 is formed integrally with the holding portion 1A by an insulating resin.

Further details will be described with reference to FIGS.

FIG. 3 is an enlarged schematic view of the main part of the brush holder shown in FIG. FIG. 4 is an enlarged schematic view of another main part of the brush holder shown in FIG.

As shown in FIG. 1, the brushed motor 100 includes a shaft 3, a pair of bearings 4 A and 4 B, a commutator 5, a brush 6, and a rotation in a housing sealed by a holding unit 1 A and a frame 2. A child 8 and a magnet 9 as a stator are provided.

In the first embodiment, the brush holder 1 is formed integrally with the holding portion 1A. The holding part 1A has a concave part 13B described later.

The frame 2 has a cylindrical shape and has a body portion 2D extending along the central axis 2C of the cylindrical shape. The frame 2 has a frame sealing end 2A at one end of the body 2D and a frame opening end 2B at the other end. In the first embodiment, the frame sealing end portion 2A is positioned to face the holding portion 1A. The frame 2 is in contact with the holding portion 1A at the frame opening end 2B. The frame sealing end 2A has a recess 13A described later.

The pair of

bearings

4A and 4B support the shaft 3. The commutator 5 is attached to the outer peripheral surface 3 A of the shaft 3. The brush 6 is in sliding contact with the commutator 5. The rotor 8 includes a core 14 and a winding 15 wound around the core 14 on the outer peripheral surface 3 A of the shaft 3. A magnet 9 as a stator is located outside the rotor 8.

As shown in FIG. 2, the dust-proof plate 10 is positioned in the direction 20 in which the commutator 5 rotates with respect to the sliding surface 17 where the brush 6 and the commutator 5 are in contact. There is a gap between the dust-proof plate 10 and the commutator 5 facing each other. Further, the dustproof plate 10 guides the brush wear powder generated when the brush 6 and the commutator 5 slide to the dust collecting unit 11.

As shown in FIG. 1, the shaft 3 is located on the center axis 2 C of the frame 2. The tip portion 3C of one shaft 3 protrudes from the frame sealing end portion 2A toward the outside of the frame 2. A bearing 4A and a bearing 4B are attached to both ends of the shaft 3, respectively. In the first embodiment, the bearing 4A is located on the tip portion 3C side of the shaft 3 and is fitted in a recess 13A included in the frame sealing end portion 2A. The bearing 4B is located on the opposite side of the tip portion 3C of the shaft 3, and is fitted in the recess 13B of the holding portion 1A. A thrust washer 16 is inserted between the bearing 4B and the recess 13B in the direction in which the axis 3B of the shaft 3 extends. The thrust washer 16 applies a pressure acting on the bearing 4B and the recess 13B in the direction in which the shaft center 3B extends.

The commutator 5 is formed of a metal material and an insulating material used for a resin mold. In the first embodiment, the commutator 5 is attached to the outer peripheral surface 3 A of the shaft 3 and is positioned closer to the holding unit 1 A than the core 14. As will be described later, the commutator 5 is biased with a brush 6 to which an elastic force is applied by a brush spring 7.

In the first embodiment, the frame 2 and the holding portion 1A constitute a casing by fitting the holding portion 1A into the frame opening end portion 2B of the frame 2. The frame 2 and the holding portion 1A are fixed by screwing or the like.

Further, the brush holder 1 is formed integrally with the holding portion 1A. The brush holder 1 and the holding part 1A are formed of an insulating resin. A brush 6 and a brush spring 7 are inserted into the brush holder 1. The brush 6 receives an elastic force from the brush spring 7 so that the brush 6 contacts the commutator 5.

The rotor 8 has a core 14 and a winding 15. The core 14 is formed by laminating steel plates. The core 14 is attached to the outer peripheral surface 3 A of the shaft 3. The winding 15 is wound around the core 14.

The magnet 9, which is a stator, is positioned to face the core 14 through a gap. The magnet 9 is attached to the inner peripheral surface 2E of the trunk portion 2D included in the frame 2.

The operation of the brushed motor 100 according to the first embodiment configured as described above will be described.

As shown in FIG. 1, the magnet 9 as a stator forms a magnetic field by the magnetic force of the magnet 9.

On the other hand, a current flows through the rotor 8 through a path to be described later. That is, in the magnetic field formed by the magnet 9, a current flows through the winding 15 of the rotor 8, so that the shaft 3 rotates in accordance with Fleming's left hand rule (Fleming's left hand rule).

The path through which current is supplied to the winding 15 refers to a path connected from the power supply located outside the brushed motor 100 to the winding 15 via the brush 6 and the commutator 5 on the positive electrode side. The current supplied to the winding 15 returns to the power supply located outside the brushed motor 100 from the commutator 5 through the negative brush 6 again.

When the shaft 3 rotates, the commutator 5 attached to the shaft 3 also rotates together with the shaft 3. The commutator 5 is biased by a brush 6 that receives an elastic force from the brush spring 7. If the commutator 5 rotates in this state, the brush 6 slides on the commutator 5. If the brush 6 is worn, brush wear powder is generated.

The generated brush wear powder is affected by the magnetic force caused by the magnet 9 and the force by which the commutator 5 rotates. Therefore, the brush wear powder is diffused toward the radial direction of the frame 2, that is, toward the inner peripheral surface 2E of the trunk portion 2D.

This will be described in more detail with reference to FIGS.

First, as shown in FIG. 3, the commutator 5 that rotates together with the shaft rotates in a rotating direction 20 indicated by an arrow in the drawing. A portion of the brush 6 that protrudes from the opening 1 B of the brush holder 1 is in contact with the commutator 5 at the sliding surface 17.

At this time, as described above, the brush wear powder 21 is affected by the magnetic force of the magnet, the force by which the commutator 5 rotates, and the like, and is diffused toward the inner peripheral surface of the trunk portion.

However, the brushed motor in the first embodiment has the dustproof plate 10 at a position facing the outer peripheral surface 5A of the commutator 5 so as to cover the sliding surface 17. If it is set as this structure, since the brush abrasion powder 21 will block the hand which goes to the dustproof board 10, spreading | diffusion will be suppressed.

Next, as shown in FIG. 4, the dust-proof plate 10 A is formed so that the brush wear powder 21 that has collided with the dust-proof plate 10 A is guided to the dust collection unit 11. In the first embodiment, the end portion 11A of the dust collecting portion 11 is connected to the end portion 10B of the dustproof plate 10A.

In this configuration, the brush wear powder 21 whose hand going to the dust-proof plate 10A is blocked is guided to the dust collecting unit 11 along the dust-proof plate 10A. Therefore, the brush wear powder 21 generated by the sliding of the brush and the commutator 5 is not diffused into the brushed motor but is accumulated in the dust collecting unit 11.

As is clear from the above description, if the brushed motor in the first embodiment is used, it is possible to prevent the brush wear powder from diffusing into the brushed motor. Therefore, it is possible to suppress a phenomenon in which the insulation resistance value decreases in an unspecified part in the motor with brush. In other words, the brushed motor in the present embodiment can maintain the insulation resistance value inside the brushed motor at a high value for a long period of time.

(Embodiment 2)
FIG. 5 is a cross-sectional view of a brushed motor according to Embodiment 2 of the present invention. FIG. 6 is a perspective view showing an outline of a brush holder used in the motor with brushes in the second embodiment of the present invention. FIG. 7 is an enlarged schematic view of a main part of the brush holder shown in FIG. FIG. 8 is an enlarged schematic view of another main part of the brush holder shown in FIG. FIG. 9 is an enlarged schematic view of still another main part of the brush holder shown in FIG.

FIG. 10 is an essential part enlarged view showing a specific example 1 of the fin used in the motor with brush in the second embodiment. FIG. 11 is an essential part enlarged view showing a specific example 2 of the fins used in the motor with brushes in the second embodiment. FIG. 12 is an essential part enlarged view showing a specific example 3 of the fins used in the brushed motor according to the second embodiment. FIG. 13 is an essential part enlarged view showing a specific example 4 of the fin used in the motor with brush in the second embodiment. FIG. 14 is an essential part enlarged view showing a specific example 5 of fins used in the motor with brush in the second embodiment. FIG. 15 is an essential part enlarged view showing a specific example 6 of the fin used in the motor with brush in the second embodiment. FIG. 16 is an essential part enlarged view showing a specific example 7 of the fin used in the motor with brush in the second embodiment. FIG. 17 is an essential part enlarged view showing a specific example 8 of the fin used in the motor with brush in the second embodiment.

The brushed motor shown in the second embodiment is different from the brushed motor described in the first embodiment in the dust collecting unit. Specifically, the motor with brush shown in the second embodiment has a plurality of fins in the dust collecting portion.

Hereinafter, description will be made with reference to FIGS.

In addition, about the same thing as the structure shown in Embodiment 1 mentioned above, the same code | symbol is attached | subjected and description is used.

As shown in FIGS. 5 and 6, the brushed motor 100 A according to the second embodiment includes a dust collection unit 31 having a plurality of fins 12. In the perspective view shown in FIG. 6, a part of the dustproof plate 10 A is omitted so that the structure of the commutator 5 can be clearly understood.

Hereinafter, explanation will be given using an enlarged drawing of the main part.

As shown in FIG. 7, the dust collection part 31 used for the motor with a brush in the second embodiment further has a plurality of fins 12 formed by a plane extending in the cross-sectional direction including the axis.

Moreover, as shown in FIG. 8, the dust collection part 31A used for the motor with a brush in the second embodiment further includes a plurality of fins 12 formed by a plane extending in the direction in which the shaft is located. Have.

As shown in FIGS. 7 and 8, the plurality of fins 12 used in the brushed motor in the second embodiment are sequentially positioned in a circumferential direction centering on the axis on the cross section orthogonal to the axis. .

Further details will be described with reference to FIGS.

As shown in FIGS. 7 and 8, the

dust collectors

31 and 31 A have a plurality of fins 12. The fin 12 is formed in a plane. The direction in which the flat surface extends may be a direction in which the opening 33 of the

dust collecting portions

31 and 31A is located from the bottom 32 of the

dust collecting portions

31 and 31A.

These configurations can increase the surface area in the

dust collecting portions

31 and 31A. Therefore, the brush wear powder 21 collected in the

dust collection portions

31 and 31A is likely to adhere to the surfaces in the

dust collection portions

31 and 31A. As a result, even if an external factor such as severe vibration is applied to the brushed motor in the second embodiment, the brush wear powder 21 collected in the

dust collecting portions

31 and 31A is again separated from the frame. It can suppress spreading | diffusion in the housing | casing formed with a holding | maintenance part.

In addition, as shown in FIG. 9, you may arrange | position the fin 12 formed in the dust collecting part 31B along the axial center direction of a shaft.

That is, as shown in FIG. 7, in the plurality of fins 12, openings 34 between adjacent fins 12 are arranged in parallel along the axial direction of the shaft. If it is this structure, it can form so that the opening part 33 of the dust collection part 31 and the opening part 34 between the adjacent fins 12 may open in the same direction. Therefore, the brush wear powder 21 can easily reach the bottom between the fins 12.

Also, as shown in FIG. 8, the plurality of fins 12 have openings 34 between adjacent fins 12 arranged in parallel along the axial direction of the shaft. Moreover, the fin 12 is inclined toward the axis of the shaft. If it is this structure, it can form so that the opening part 33 of 31 A of dust collection parts and the opening part 34 between the adjacent fins 12 may open in the same direction. Moreover, the inclination between the adjacent fins 12 also has an inclination toward the axis of the shaft. Therefore, it becomes easier for the brush wear powder 21 to reach the bottom between the fins 12.

Furthermore, as shown in FIG. 9, the plurality of fins 12 have openings 34 between adjacent fins 12 arranged in parallel along the rotation direction of the commutator. In this configuration, the direction in which the brush wear powder 21 generated by the rotation of the commutator flows into the opening 33 of the dust collecting portion 31B and the opening 34 between the adjacent fins 12 are in the same direction. Can be formed. Therefore, it becomes easy for the brush wear powder 21 to reach the bottom portion between the fins 12.

Next, the fin used in the motor with brush shown in the second embodiment has a surface roughness enough to prevent the brush wear powder adhering to the plane from scattering.

Further, as shown in FIGS. 10 to 13, the fin 12 used in the motor with brush shown in the second embodiment has

convex portions

40, 40A, 40B, and 40C on the surface.

Alternatively, as shown in FIGS. 14 to 17, the fin 12 used in the motor with brush shown in the second embodiment has

concave portions

41, 41A, 41B, and 41C on the surface.

Further details will be described with reference to FIGS. 10 to 17.

The fin 12 is processed so that the surface roughness of the surface of the fin 12 is increased. The surface roughness is such that brush wear powder adhering to the surface of the fin 12 is prevented from scattering again.

Next, there are two methods as specific modes for increasing the surface area in the

dust collecting sections

31, 31A, 31B. Hereinafter, the aspect using a convex part is as follows. Will be described. Moreover, the aspect using a recessed part is 2. Will be described.

1. Specific Example 1 to Specific Example 4 As shown in FIGS. 10 and 11, protrusions shown as

convex portions

40 and 40 A are formed on the surface of the fin 12. Or as shown in FIG. 12, FIG. 13, on the surface of the fin 12, the convex-shaped part shown as

convex part

40B, 40C is formed.

With these configurations, the surface area of each fin 12 can be increased. Therefore, the brush wear powder 21 collected in the

dust collecting portions

31, 31A, 31B shown in FIGS. 7 to 9 is likely to adhere to the surfaces in the

dust collecting portions

31, 31A, 31B. As a result, even if an external factor such as severe vibration is applied to the motor with the brush in the second embodiment, the brush wear powder 21 collected in the

dust collecting portions

31, 31A, 31B is again It can suppress spreading | diffusion in the housing | casing formed with the flame | frame 2 and the holding | maintenance part 1A.

Particularly, the

convex portions

40A and 40C shown in FIGS. 11 and 13 have the following shapes. That is, in the

protrusions

40A and 40C, the upper surface 43 located on the tip 42 side of the protrusion or the protrusion is inclined to the bottom 32 side. As for

convex part

40A, 40C, the lower surface 44 located in the bottom part 32 side of a protrusion or a convex-shaped part has faced the bottom part 32 side.

With these structures, the brush wear powder 21 reaches the bottom 32 between the adjacent fins 12 because the brush wear powder 21 slides on the upper surface 43 in the opening 34 between the adjacent fins 12 shown in FIGS. It becomes easy. On the other hand, since the brush wear powder 21 arriving at the bottom 32 between the adjacent fins 12 is blocked by the lower surface 44, the openings of the

dust collecting portions

31, 31 A, and 31 B again from the bottom 32 between the adjacent fins 12. Through 33, it is possible to suppress diffusion.

2. About Specific Example 5 to Specific Example 8 As shown in FIGS. 14 and 15, depressions shown as

concave portions

41 and 41 A are formed on the surface of the fin 12. Alternatively, as shown in FIGS. 16 and 17, concave grooves shown as concave portions 41 B and 41 C are formed on the surface of the fin 12.

dust collecting portions

31, 31A, 31B shown in FIGS. 7 to 9 is likely to adhere to the surfaces in the

dust collecting portions

Particularly, the recesses 41A and 41C shown in FIGS. 15 and 17 have the following shapes. That is, in the recesses 41 A and 41 C, the lower surface 45 positioned on the bottom 32 side of the recess or the concave groove is inclined toward the bottom 32 side. In the recesses 41 A and 41 C, the upper surface 46 positioned on the tip 42 side of the recess or the concave groove faces the bottom 32 side.

With these configurations, the brush wear powder 21 arrives at the bottom 32 between the adjacent fins 12 because the brush wear powder 21 slides on the lower surface 45 in the openings 34 between the adjacent fins 12 shown in FIGS. It becomes easy to do. On the other hand, since the brush wear powder 21 arriving at the bottom 32 between the adjacent fins 12 is blocked by the upper surface 46, the openings of the

dust collecting portions

31, 31A, 31B again from the bottom 32 between the adjacent fins 12. Through 33, it is possible to suppress diffusion.

As is apparent from the above description, the brushed motor according to the second embodiment forms a plurality of fins in the dust collecting portion. Furthermore, the motor with a brush in the second embodiment forms a convex part or a concave part on the surface of each fin.

</ RTI> By adopting these configurations, the surface area in the dust collecting part becomes larger. As a result, the brush wear powder collected in the dust collection part is likely to adhere to the surface in the dust collection part. In other words, the dust collection part improves the holding power of the brush wear powder.

Therefore, in the motor with a brush according to the second embodiment, it is possible to suppress the release of the brush wear powder from the dust collecting portion toward the inside of the casing due to an external factor.

As a result, it is possible to suppress the phenomenon that the insulation resistance value decreases in an unspecified portion in the brushed motor. In other words, the brushed motor in the present embodiment can maintain the insulation resistance value inside the brushed motor at a high value for a long period of time.

The brushed motor in the present invention makes it difficult for the brush wear powder to scatter inside the brushed motor. Therefore, the present invention is particularly effective for automotive electrical parts, industrial equipment, and the like that are difficult to replace motors or maintain motors.

DESCRIPTION OF SYMBOLS 1 Brush holder

1A Holding part

1B Opening part 2 Frame 2A Frame sealing end part 2B Frame opening end part

2C Central axis

2D Trunk part 2E Inner peripheral surface 3

Shafts

3A, 5A Outer peripheral surface 3B Axes 3C, 42

Tip parts

4A, 4B, 4C, 4D bearing 5 commutator 6 brush 7 brush spring 8 rotor 9 magnet (stator)
10, 10A Dust-

proof plate

10B,

11A End portion

11, 31, 31A, 31B Dust collection portion 12

Fin

13A, 13B Recess 14 Core 15 Winding 16 Thrust washer 17 Sliding surface 20 Direction of rotation 21 Brush wear powder 32

Bottom portion

33, 34

Opening

40, 40A, 40B,

40C Convex

41, 41A, 41B,

41C Concave

43, 46

Top

44, 45

Bottom

100, 100A Brushed motor 110 Rib 111 Pocket

Claims

A rotor having a shaft and a commutator located on the outer peripheral surface of the shaft, and rotating about the axis of the shaft;
A pair of bearings for rotatably supporting the shaft;
A brush holder that forms a pair of positive and negative electrodes, has an opening at a position facing the commutator, and faces the commutator along a radial direction of the shaft orthogonal to the axis;
A brush located in the brush holder of each of the positive and negative electrodes, movable along the radial direction, and in contact with and sliding on the sliding surface with the commutator through the opening;
In the brush holder of each of the positive and negative electrodes, an elastic member positioned so as to press the brush against the commutator;
A holding part for holding the brush holder,
The holding part is
Between the pair of brush holders, a dustproof plate facing the commutator and positioned along the axial direction of the shaft;
A motor with a brush, comprising: a dust collecting part that accumulates brush wear powder generated when the brush and the commutator slide through the dust-proof plate.
The dust-proof plate is positioned opposite to the outer peripheral surface of the commutator in a circumferential direction centering on the shaft center on a cross section orthogonal to the shaft center, and at least in a gravitational direction with respect to the commutator The brushed motor according to claim 1, which is located in
The dust-proof plate is positioned opposite to the outer peripheral surface of the commutator in a circumferential direction centered on the shaft center on a cross section orthogonal to the shaft center, and at least in a direction in which the commutator rotates. The brushed motor according to claim 1, which is located on the downstream side.
The motor with a brush according to claim 1, wherein the dustproof plate is formed to guide the brush wear powder to the dust collecting portion.
The brushed motor according to claim 1, wherein the dust collection unit further includes a plurality of fins formed by a plane extending in a cross-sectional direction including the axis.
The brushed motor according to claim 1, wherein the dust collection unit further includes a plurality of fins formed by a plane extending in a direction in which the shaft is located.
The brush motor according to claim 5, wherein the plurality of fins are sequentially positioned in a circumferential direction centering on the axis on a cross section orthogonal to the axis.
The brush motor according to any one of claims 5 and 6, wherein the fin has a surface roughness that prevents the brush wear powder adhering to the flat surface from scattering.
The brushed motor according to claim 5, wherein the fin has a convex portion on the surface.
The brush motor according to claim 5, wherein the fin has a recess on the surface.
The brushed motor according to any one of claims 1 to 6, wherein the brush holder is formed integrally with the holding portion by an insulating resin.