JP2003199300A - Brush device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a brush device capable of effectively suppressing a brush from rattling in the rotative direction of a commutator relative to a brush holder. <P>SOLUTION: In a brush device 4, a brush 6 is housed/held together with a gap in a brush holder 5 extending almost in the radial direction of the commutator. When the rear end of the brush 6 is energized to a one-end-side protruding part 7b of a torsion spring 7, the tip of the brush 6 is pressurized and contacted to the commutator. A U-shape part 11 which is almost U-like is formed at an other-end-side protruding part 7c of the torsion spring 7. The brush 6 is pressurized against a rotative-direction-side side-wall 5b of the brush holder 5 when energized to the rotative-direction side side-wall 5b side by the U-shaped part 11. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brush device for bringing a brush into contact with a commutator of a motor.

[0002]

2. Description of the Related Art Conventionally, a rotating shaft of a DC motor is provided with a commutator (commutator), and a pair of power supply brushes are in contact with the commutator. As a brush device for bringing the brush into contact with the commutator, the brush is housed and held in a brush holder extending in the radial direction of the commutator, and the rear end of the brush is biased to one end of a torsion spring (torsion coil spring). As a result, the tip of the brush is pressed into contact with the commutator in some cases. The other end of the torsion spring is fixed to the stator side member (the substrate or the like) like the brush holder.

In the brush device constructed as described above, when the rotor rotates, the brush comes into sliding contact with the commutator, so that an external drive current is supplied to the rotor through the brush and the commutator.

In the brush device as described above, the inside (inside surface) of the brush holder has a gap in consideration of thermal expansion of the brush and the like when the brush in a cooled state (normal temperature) is accommodated. Is set. Therefore, it is possible to prevent the brush holder from hindering the movement of the brush in the front-rear direction even when the brush becomes hot and expands when the rotor rotates for a long time.

[0005]

However, in the brush device as described above, for example, when the rotor (commutator) starts rotating (at the time of starting), the brush rotates due to the frictional force with the commutator. It may rattle in the direction. In this case, one end of the brush in the rotation direction of the commutator is separated (raised) from the commutator, and the contact area between the brush and the commutator becomes small. Then, the drive current does not flow normally from the brush to the commutator. Therefore, in the motor as described above, there is a possibility that desired rotation characteristics may not be obtained, especially at the time of starting. Further, for example, when the rotor rotates, the brush may repeatedly vibrate and vibrate to cause vibration noise.

Therefore, by tilting the rear end surface of the brush and urging the rear end surface with a compression coil spring, the front end portion of the brush is pressed into contact with the commutator, and the rear end portion of the brush is attached to the brush holder. Some push against the side wall in the rotation direction (side wall in the rotation direction of the commutator). In this brush device, the rear end portion of the brush can be pressed against the rotation direction side wall of the brush holder without increasing the number of parts, and thus the rattling can be reduced. However, in the above brush device, since it is pressed by the component force of the compression coil spring due to the inclined rear end surface, it is difficult to increase the pressing force, and
There is a problem that the rattling (vibration) of the tip portion of the brush, which is easily rattled, cannot be effectively suppressed. Further, in this brush device, the compression coil spring is arranged further outside in the radial direction of the rear end of the brush, and in a motor having a small space for arranging the commutator in the radial direction, the disposition is more difficult than in the torsion spring. Become.

The present invention has been made to solve the above problems, and an object thereof is to effectively prevent rattling of the brush with respect to the brush holder in the rotating direction of the commutator. To provide a device.

[0008]

According to a first aspect of the invention, the brush is accommodated and held in a brush holder extending in a substantially radial direction of the commutator with a gap, and the brush is attached to one end of the torsion spring. In the brush device in which the tip end is pressed and brought into contact with the commutator by being urged, the brush is pressed against the rotation direction side wall of the brush holder by the other end of the torsion spring.

According to a second aspect of the present invention, in the brush device according to the first aspect, the other end of the torsion spring is
By urging at least the tip of the brush, the brush is pressed against the side wall in the rotation direction.

According to a third aspect of the present invention, in the brush device according to the second aspect, the other end of the torsion spring is
A radial extension portion is provided from the front end portion to the rear end portion side of the brush so as to make a long contact in the radial direction of the commutator.

The invention according to claim 4 is the invention according to claims 1 to 3.
In the brush device according to any one of items 1 to 3, an axially extending portion that is in contact with the brush and the commutator for a long time in an axial direction is provided at the other end of the torsion spring.

According to a fifth aspect of the present invention, in the brush device according to the second aspect, the other end of the torsion spring is
A substantially U-shaped U-shaped portion having parallel parallel portions and a connecting portion connecting one end of the parallel portion is provided, and the parallel portion is provided in a radial direction of the commutator from a front end portion to a rear end portion side of the brush. It was arranged so as to make long contact, and the connecting portion was arranged so as to make long contact at the tip of the brush in the axial direction of the brush and the commutator.

(Operation) According to the invention described in claim 1,
When the brush is biased by one end of the torsion spring, the tip end of the brush comes into pressure contact with the commutator, and the other end of the brush is pressed against the side wall of the brush holder in the rotational direction, which constitutes a part of the brush holder. Therefore, it is possible to effectively prevent the brush from rattling (vibrating) in the rotation direction of the commutator, for example, when the commutator starts rotating. Moreover, the number of parts does not increase.

According to the second aspect of the present invention, the brush is pressed against the side wall in the rotational direction by biasing at least the tip end portion of the other end of the torsion spring. Further, since the tip side of the brush, which is the contact surface side with the commutator, is easily rattled, it is possible to further suppress the rattling (vibration) of the brush in the rotation direction of the commutator.

According to the third aspect of the present invention, the other end of the torsion spring is provided with a radially extending portion that abuts in a long direction in the radial direction of the commutator from the front end portion to the rear end portion side of the brush. Therefore, the brush is urged from the front end to the rear end side. Therefore, it is possible to further prevent the brush from rattling (vibrating) in the rotation direction of the commutator.

According to the invention as set forth in claim 4, since the axially extending portion which is in contact with the brush and the commutator for a long time in the axial direction is provided at the other end of the torsion spring, the brush has an axial direction. Is energized in a long range. Therefore, it is possible to further prevent the brush from rattling (vibrating) in the rotation direction of the commutator.

According to the invention described in claim 5, at the other end of the torsion spring, there is a substantially U-shaped U-shaped portion having a parallel parallel portion and a connecting portion connecting one end of the parallel portion. It is provided. The parallel portion is arranged so as to abut in the radial direction of the commutator from the front end portion to the rear end portion side of the brush, and the connecting portion is long in the axial direction of the brush and the commutator at the front end portion of the brush. Arranged to touch. Therefore, the brush is urged from the front end portion to the rear end portion side by the pair of parallel portions arranged in the axial direction of the commutator. Moreover, the brush is urged by the connecting portion in the axially long range. Therefore, it is possible to further suppress the rattling (vibration) of the brush in the rotation direction of the commutator while the other end of the torsion spring has a simple shape.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in a motor will be described below with reference to FIGS.

As shown in FIG. 1, a DC motor 1 is arranged in the vicinity of the rotary shaft 2, a substantially cylindrical commutator (commutator) 3 fixed to the rotary shaft 2, and the commutator 3. And a pair of brush devices 4. Each brush device 4 includes a brush holder 5, a brush 6, and a torsion spring (torsion coil spring) 7.

The brush holder 5 is erected on the substrate 8,
It is formed so as to extend in the radial direction of the commutator 3 so as to accommodate and hold the brush 6 having a substantially rectangular prism shape inside. For more information,
The brush holder 5 is composed of side walls 5a and 5b on the rotational direction side, an upper portion 5c, and a lower portion 5d (see FIG. 2). The rotation direction side sidewalls 5a and 5b are erected on the substrate 8 and arranged in parallel on the rotation direction side of the commutator 3 so as to extend in the radial direction of the commutator 3. The upper portion 5c is formed so as to connect the upper end portions (the end portions in the standing direction) of the pair of rotation direction side sidewalls 5a and 5b. The lower portion 5d is a part of the substrate 8 and is formed so as to connect the lower end portions of the pair of rotation direction side sidewalls 5a and 5b. Here, the distance between the pair of rotation-direction side walls 5a and 5b is set between the brushes 6 when the brushes 6 in a cold state (normal temperature) are accommodated in consideration of thermal expansion of the brushes 6 accommodated therein. Is set to have a gap.

On one side (clockwise direction side in FIG. 1) of the rotational direction side wall 5a, a notch extending from its tip (radially inward of the commutator 3) to its rear end (radially outward of the commutator 3). The portion 5e (see FIG. 2) is formed.

In the upper portion 5c, the side walls 5a on both sides in the rotation direction,
An upper end slit 5f that extends radially inward from the center of the rear end portion (radial outer end) and penetrates in the rotation axis direction is formed in an intermediate portion between 5b. The pigtail 6a of the brush 6 housed inside the brush holder 5 penetrates the upper end slit 5f and projects outward (upward), and is connected to a control device (power supply device) (not shown) outside the DC motor 1.

The torsion spring 7 is composed of a coil portion 7a, one end side protruding portion 7b protruding from one end of the coil portion 7a, and another end side protruding portion 7c protruding from the other end of the coil portion 7a. The torsion spring 7 is held by the coil portion 7a being externally fitted to a column 8a standing upright in the vicinity of the brush holder 5 of the substrate 8 (in the present embodiment, in the clockwise side of the brush holder 5). Has been done.

The projection 7b on one end side of the torsion spring 7 is
The brush holder 5 is formed so as to enter the inside of the brush holder 5 through the open rear end portion (radially outer end portion) and the upper end slit 5f and be bent so as to be able to contact the rear end portion of the brush 6.

As shown in FIG. 2, the other end side protrusion 7c of the torsion spring 7 has a pair of parallel parallel portions 11a and 11b as a radially extending portion and the parallel portions 11a and 11b.
-Shaped portion 11 having a connecting portion 11c as an axially extending portion that connects one end portion (radially inner end portion of the commutator 3) of the
Are formed. The parallel portions 11a and 11b are provided on one side surface (the clockwise side surface in FIG. 1) of the brush 6,
The commutator 3 is formed so as to be abuttable in the radial direction from the front end to the rear end for a long time. Also, the connecting portion 11c is
The tip of one side surface (a clockwise side surface in FIG. 1) of the brush 6 is formed so as to be capable of abutting on the brush 6 for a long time in the rotation axis direction. The U-shaped portion 11 (parallel portion 11a,
11b and the connecting portion 11c) enter the inside of the brush holder 5 through the cutout portion 5e and come into contact with one side surface of the brush 6. Further, since the pair of parallel portions 11a and 11b are connected to the connecting portion 11c which is parallel and extends in the rotation axis direction, the diameter of the commutator 3 is two at the brush 6 and two points in the rotation axis direction (upper side and lower side). It will make a long contact in the direction. The torsion spring 7 is configured such that the tip of the one end side protruding portion 7b urges the rear end portion of the brush 6 toward the commutator 3 side, and the U-shaped portion 11 is located on one side surface of the brush 6 (in FIG. 1). , The clockwise side surface) is urged toward the other (counterclockwise direction side in FIG. 1) rotational direction side wall 5b. Therefore, the tip of the brush 6 is pressed into contact with the commutator 3, and the other side surface (counterclockwise side surface in FIG. 1) of the brush 6 is on the rotation direction side wall 5b.
Is pressed by.

In the DC motor 1 (brush device 4) configured as described above, the brush 6 is in sliding contact with the commutator 3, so that the brush 6 and the commutator 3 from the control device (power supply device) even when the rotor is rotating. A drive current is supplied to the rotor, more specifically, to the winding wound around the armature core (not shown).

The gap between the pair of side walls 5a and 5b on the rotation direction side of the brush holder 5 is set so that there is a gap between the brush 6 and the brush 6 when the brush 6 is stored in a cold state (normal temperature). Therefore, the brush holder 5 is prevented from obstructing the movement of the brush 6 in the front-rear direction even if the brush 6 becomes hot and expands when the rotor rotates for a long time.

The characteristic effects of the above embodiment will be described below. (1) The brush 6 has a protruding portion 7 on one end side of the torsion spring 7.
The tip end of the brush holder 5 is pressed against the commutator 3 by being urged toward the tip of the b, and the U-shaped portion 11 formed on the other end side protruding portion 7c of the torsion spring 7 causes the side wall of the brush holder 5 in the rotational direction. 5b is pressed. Therefore, for example, when the commutator 3 starts rotating, it is possible to effectively prevent the brush 6 from rattling (vibrating) in the rotation direction of the commutator 3. Moreover, the number of parts does not increase.

(2) The brush 6 has a radially inner end of the U-shaped portion 11 of the torsion spring 7 (parallel portions 11a, 11).
The radially inner end of b and the tip of one side surface are urged by the connecting portion 11c) to be pressed against the rotation direction side wall 5b. Further, since the tip end side of the brush 6 which is the contact surface side with the commutator 3 is easily rattled, rattling (vibration) of the brush 6 in the rotation direction of the commutator 3 is further suppressed.

(3) In the U-shaped portion 11 of the torsion spring 7, the commutator 3 extends from the front end of the brush 6 to the rear end thereof.
Since the parallel portions 11a and 11b that are long in contact with each other in the radial direction are provided, the brush 6 is biased from the front end portion to the rear end portion side. Therefore, rattling (vibration) of the brush 6 in the rotation direction of the commutator 3 is further suppressed.

(4) Since the U-shaped portion 11 of the torsion spring 7 is provided with the connecting portion 11c that abuts on the brush 6 in the rotation axis direction (axial direction of the commutator 3) for a long time, the brush 6 moves in the rotation axis direction. Activated over a long range. Therefore, rattling (vibration) of the brush 6 in the rotation direction of the commutator 3 is further suppressed.

(5) The other end side protruding portion 7 of the torsion spring 7
C is a U-shaped portion 1 including a pair of parallel parallel portions 11a and 11b and a connecting portion 11c that connects the parallel portions 11a and 11b.
1 was set. By doing so, it is possible to obtain the above-mentioned effects (2) to (4) while having a simple U-shape. Moreover, since the pair of parallel portions 11a and 11b are in long contact with the brush 6 in the radial direction of the commutator 3 at two locations (upper side and lower side) in the rotational axis direction, the brush 6 rattles in the rotational direction of the commutator 3 ( Vibration) is further suppressed.

(6) Since the torsion spring 7 is arranged on the clockwise side of the brush holder 5, in a motor in which the commutator 3 has a small radial arrangement space as compared with a brush device using a compression coil spring. Also, its arrangement (design) becomes easy.

The above embodiment may be modified as follows. In the above embodiment, the U-shaped portion 11 having a substantially U-shape is formed on the other end side protruding portion 7c of the torsion spring 7, but the brush 6 is rotated in the rotation direction side by the other end side protruding portion (the other end). If it is possible to press against the side wall 5b, the U-shaped portion 11 may not be particularly formed, and the other end may be changed to another shape. Even in this case, the brush 6 is pressed against the rotation direction side wall 5b of the brush holder 5 by the other end of the torsion spring. Therefore, for example, when the commutator 3 starts rotating,
It is possible to effectively prevent the brush 6 from rattling (vibrating) in the rotation direction of the commutator 3. Moreover,
The number of parts does not increase.

For example, the U-shaped portion 11 has a shape of only one parallel portion 11a (extending in the radial direction) (the other parallel portion 11).
b and the connecting portion 11c are not formed). Even in this case, since the brush 6 is biased from the front end portion to the rear end portion side, rattling (vibration) of the brush 6 in the rotation direction of the commutator 3 is further suppressed.

Further, for example, the U-shaped portion 11 is formed with only one parallel portion 11a (radially extending portion) and the connecting portion 11c (axially extending portion) having the shape (the other parallel portion 11b). No) may be changed. Even in this case, the brush 6 is urged from the front end to the rear end, and
Since the brush 6 is biased in a long range in the rotation axis direction, the brush 6
Rattling (vibrating) in the rotation direction of the commutator 3 is further suppressed.

In the above embodiment, the upper slit 5f is formed in the upper portion 5c. The one end side protruding portion 7b of the torsion spring 7 is formed so as to enter the inside of the brush holder 5 through the open rear end portion and the upper end slit 5f of the brush holder 5 and contact the rear end portion of the brush 6.
May be biased toward the commutator 3 side, the shape of the brush holder 5 or the shape of the one end side protruding portion 7b may be changed to another shape. Even in this case, the same effect as that of the above-described embodiment can be obtained.

In the above embodiment, the brush device 4 is embodied as a motor having a pair (two).
May be embodied in a motor having another number (for example, three) (for example, a wiper motor). Even in this case, the same effect as that of the above-described embodiment can be obtained.

The technical idea that can be understood from the above-described embodiment will be described below along with its effects. (A) A motor comprising the brush device (4) according to any one of claims 1 to 5. With this configuration, it is possible to provide a motor that can effectively prevent the brush from rattling with respect to the brush holder in the rotation direction of the commutator.

[0040]

As described in detail above, according to the present invention,
It is possible to provide a brush device that can effectively prevent the brush from rattling with respect to the brush holder in the rotation direction of the commutator.

[Brief description of drawings]

FIG. 1 is a sectional view of a main part of a motor according to the present embodiment.

FIG. 2 is a perspective view of the brush device according to the present embodiment.

[Explanation of symbols]

3 ... commutator, 5 ... brush holder, 6 ... brush, 7
... torsion spring, 11 ... U-shaped portion that constitutes a part of the other end of the torsion spring, 5b ... side wall in the direction of rotation, 7b ... one end side protruding portion that constitutes one end of the torsion spring, 7c ... other end of the torsion spring The other end side protruding portion which constitutes a part, 11
a, 11b ... Parallel part (radially extending part), 11c ... Connection part (axially extending part).

Continued front page    F term (reference) 5H605 BB05 BB09 CC03 CC07 CC10                       EA12 EA25                 5H613 AA01 BB04 BB15 BB28 GA13                       GA15 KK05 SS05

Claims (5)

[Claims] 1. A brush holder (5) extending substantially in the radial direction of a commutator (3) is accommodated and held with a brush (6) having a gap, and the brush (6) is at one end of a torsion spring (7). In the brush device, the tip of which is pressed into contact with the commutator (3) by being urged by (7b), the brush (6) is connected to the other end (7c, 11) of the torsion spring (7). The brush device is characterized in that it is pressed against the side wall (5b) of the brush holder (5) in the rotation direction. 2. The brush device according to claim 1, wherein the other end (7c, 11) of the torsion spring (7) urges at least a tip portion of the brush (6). ) Is pressed against the side wall (5b) on the rotation direction side. 3. The brush device according to claim 2, wherein the other end (7c, 11) of the torsion spring (7) is provided with the commutator (3) from a front end portion to a rear end portion side of the brush (6). The radially extending portion (11
a, 11b) is provided. 4. The brush device according to any one of claims 1 to 3, wherein the other end (7c, 11) of the torsion spring (7) is provided with the brush (6) and the commutator (3). A brush device comprising an axially extending portion (11c) that is long in contact with the axial direction. 5. The brush device according to claim 2, wherein a parallel portion (1) parallel to the other end of the torsion spring (7) is provided.
1a, 11b) and a connecting portion (11c) connecting one ends of the parallel portions (11a, 11b) to each other, and a U-shaped portion (11) having a substantially U shape is provided, and the parallel portions (11a, 11b) are The brush (6) is arranged so as to make long contact in the radial direction of the commutator (3) from the front end portion to the rear end portion side, and the connecting portion (11c) is provided at the front end portion of the brush (6). ) And the commutator (3) are arranged so as to make long contact with each other in the axial direction.