JP2003052152A - Brush device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a brush device, capable of restraining a brush from rattling in the rotational direction of a commutator. SOLUTION: The brush device is structured, so that the brush 6 is accommodated and held in a brush holder 5 extending in the radial direction of the commutator 3, and the front end part of the brush 6 is brought into pressure contact with the commutator 3. An inclined surface 6a, inclined with respect to the axial direction of the commutator 3, is formed at one side surface in the rotation direction of the commutator 3 in the brush 6. The brush 6 is energized to the commutator 3 side by the energization force of a coil spring 7, and is energized in the facing-side axial direction which is an axial direction on the side facing the inclined surface 6a by the component force of a coil spring 7 by a rear end inclined surface 6c formed at the brush 6. A complete circle bar 9, which is engaged with the inclined surface 6a in the axial direction of the commutator 3, is provided on one rotation-direction sidewall 5a facing the inclined surface 6a, of the rotation-direction sidewalls 5a, 5b which are arranged side by side in a pair in the rotational direction of the commutator 3 and constitute part of the brush holder 5.

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 DC motor is provided with a pair of brush devices as shown in FIG. In this brush device, a brush 93 is accommodated and held in a brush holder 92 extending in a radial direction of a commutator 91 provided on an armature (rotor) not shown, and a rear end portion of the brush 93 is biased by a coil spring 94. The tip of the brush 93 is pressed against the commutator 91.

In the brush device constructed as described above, since the brush 93 is in sliding contact with the commutator 91 during rotation of the rotor, a drive current from the outside is wound around the rotor, more specifically, the armature core. The wire is supplied via a brush 93 and a commutator 91.

By the way, in the brush device as described above, the inside of the brush holder 92 (inside surface) is a brush 93.
In consideration of the thermal expansion of the
It is set to have a gap when 3 is accommodated. Therefore, when the rotor is rotated for a long time, the brush 93
The brush holder 92 will not
It is prevented that the movement of the vehicle in the front-back direction is hindered.

[0005]

However, in the brush device as described above, for example, when the rotor (commutator 51) starts rotating (at the time of starting), the brush 9 is used.
3 may rattle in the rotation direction of the commutator 91 due to the frictional force with the commutator 91. In this case, one end of the tip of the brush 93 in the rotation direction of the commutator 91 is separated (raised) from the commutator 91, and the contact area between the brush 93 and the commutator 91 becomes small. Then the brush 93
Therefore, the drive current does not flow normally to the commutator 91. Therefore, in the motor as described above, especially when starting up,
There is a possibility that desired rotation characteristics may not be obtained.

Further, in the brush device as described above, for example, the brush 9 is rotated while the rotor (commutator 91) is rotating.
The frictional force of 3 with the commutator 91 may rattle and vibrate in the rotation direction of the commutator 91. Therefore, the motor as described above has a problem that noise is generated based on the vibration of the brush 93 during rotation.

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

[0008]

According to a first aspect of the present invention, there is provided a brush device in which a brush is accommodated and held in a brush holder extending in a radial direction of a commutator, and a tip end portion of the brush is pressed into contact with the commutator. , One side surface of the brush in the rotating direction of the commutator,
An inclined surface that is inclined with respect to the axial direction of the commutator is formed, the brushes are biased in the axial direction on the opposite side, which is the axial direction on the side facing the inclined surface, and a pair of them are arranged side by side in the rotation direction of the commutator. An engaging portion that engages the inclined surface and the commutator in the axial direction is provided on one rotational direction side wall facing the inclined surface of the rotational direction side wall forming a part of the brush holder. It was

According to a second aspect of the present invention, in the brush device according to the first aspect, the inclined surface is one bottom surface of a V-shaped groove formed on a side surface of the brush. According to a third aspect of the present invention, in the brush device according to the first or second aspect, the engaging portion is a curved portion that is convex toward the inclined surface.

According to a fourth aspect of the present invention, in the brush device according to the third aspect, the curved portion is a perfect circle shape fixed to the one side wall in the rotation direction so as to project toward the inclined surface side. It is a perfect circle.

According to a fifth aspect of the present invention, in the brush device according to the third aspect, the curved portion is a semicircular convex portion that protrudes in a semicircular shape on the inclined surface side. According to a sixth aspect of the present invention, in the brush device according to any one of the first to fifth aspects, a rear end portion of the brush is a non-opposing side shaft that is an axial direction on a side that does not face the inclined surface. A rear end inclined surface is formed so as to be closer to the commutator side in the direction, and a biasing means for contacting the rear end inclined surface and biasing the commutator side is provided behind the brush.

(Operation) According to the invention described in claim 1,
An inclined surface that is inclined with respect to the axial direction of the commutator is formed on one side surface of the brush in the rotation direction of the commutator, and the brush is in the opposite axial direction that is the axial direction on the side facing the inclined surface. Be energized. In addition, a pair of the rotation direction side sidewalls that are arranged side by side in the rotation direction of the commutator and form a part of the brush holder, and the one of the rotation direction side sidewalls that faces the slope surface have the slope surface and the slope surface. An engaging portion that engages in the axial direction of the commutator is provided.

Therefore, by the action of the inclined surface and the engaging portion, the brush is moved in the opposing axial direction until the side surface on the opposite side of the inclined surface comes into contact with the opposed rotation direction side wall. As a result, the brush comes into contact with both side surfaces including the inclined surface in the rotational direction side wall including the engaging portion in the rotational direction of the commutator. This prevents the brush from rattling with respect to the brush holder in the rotation direction of the commutator. Even if the brush becomes hot and expands with respect to the brush holder, the brush moves in the non-opposing side axial direction, which is the axial direction on the side not facing the inclined surface. It will not be pinched by the side wall. Therefore, the brush is prevented from rattling with respect to the brush holder in the rotating direction of the commutator, and the brush holder is prevented from obstructing the movement of the brush in the front-rear direction.

According to the second aspect of the present invention, since the inclined surface is one bottom surface of the V-shaped groove formed on the side surface of the brush, the engaging portion engaging with the inclined surface is V-shaped. A space for entering the inside of the groove is secured, and the inclined surface can be easily formed.

According to the third aspect of the present invention, since the engaging portion is a curved portion that is convex toward the inclined surface, the brush is allowed to incline on the curved portion side. Therefore, even if the precision of each component is not high, the side surface of the brush opposite to the inclined surface is in surface contact with the opposing rotation direction side wall, and rattling in the rotation direction of the commutator is suppressed.

According to the fourth aspect of the present invention, since the curved portion is a true circular rod which is fixed to the one side wall in the rotation direction so as to project toward the inclined surface, The brush is allowed to tilt on the curved portion side.

According to the fifth aspect of the invention, since the curved portion is a semicircular convex portion that protrudes in a semicircular shape toward the inclined surface side, the brush is allowed to incline on the curved portion side. . According to the invention of claim 6, a rear end inclined surface is formed at the rear end portion of the brush so as to be closer to the commutator side in the axial direction on the non-opposing side, which is the axial direction on the side not facing the inclined surface. In the rear of the brush, an urging means for contacting the rear end inclined surface and urging the brush toward the commutator is provided. Therefore, the brush is urged toward the commutator side by the urging force of the urging means, and is urged in the opposite axial direction by the component force of the urging means by the rear end inclined surface.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment in which the present invention is embodied in a DC 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. A pair of brush devices 4 (one pair at 180 degree intervals) are provided. Then, each brush device 4 has a brush holder 5
A brush 6 and a coil spring 7 as a biasing means.
It has and.

The brush holder 5 is made of a resin material and is integrally formed on a substrate 8 fixed to a motor case (not shown). The brush holder 5 has a commutator 3 for accommodating and holding the brush 6 and the coil spring 7 therein.
Is formed so as to extend in the radial direction. Specifically, the brush holder 5 extends in the radial direction of the commutator 3, and a pair of rotation-direction-side side walls 5 are arranged in parallel on the rotation-direction side of the commutator 3.
a, 5b, a rear end wall 5c formed so as to connect the rear end side of the pair of rotation direction side walls 5a, 5b (the radial outer side of the commutator 3), and the upper ends of the pair of rotation direction side wall 5a, 5b. And an upper part 5d and a lower part 5 formed so as to cover the lower end
e (see FIG. 2) and the like. On one side (clockwise direction side) of the rotation direction side wall 5a, a round bar 9 as an engaging portion and a bending portion is fixed to the inside of the brush holder 5. The true circle bar 9 is set to have a length substantially equal to the radial length of the commutator 3 on the rotation direction side wall 5a, and is located at the axial center of the commutator 3 on the rotation direction side wall 5a and in the radial direction of the commutator 3. It is arranged to extend to. In addition, as shown in FIG.
As shown in (b), a slit 5f extending in the radial direction of the commutator 3 is formed.

The brush 6 is formed in a substantially quadrangular prism shape. An inclined surface 6a that is inclined with respect to the axial direction of the commutator 3 is formed on a side surface of the brush 6 that faces the one rotation-direction-side side wall 5a (the true circular rod 9). For more information,
One side wall 5a of the brush 6 on the rotational direction side (a true circular rod 9)
As shown in FIG. 2A, a V-shaped groove 6b having a substantially V-shaped cross-section when viewed from the radial direction of the commutator 3 is provided on the side surface facing the
Are formed along the radial direction of the commutator 3, and the bottom surface above the V-shaped groove 6b (upper side in FIG. 2A) is the inclined surface 6.
It is a.

The width of the commutator 3 in the rotation direction in the portion of the brush 6 where the V-shaped groove 6b is not formed is smaller than the distance between the pair of rotation direction side walls 5a and 5b in the same direction, and It is set to be larger than the distance in the same direction from the circular bar 9 to the other side wall 5b in the rotation direction.
The minimum width of the commutator 3 in the rotation direction at the portion of the brush 6 where the V-shaped groove 6b is formed is the round bar 9
To the other side wall 5b on the rotation direction side in the same direction.

Further, above the rear end of the brush 6 (the radially outer end of the commutator 3) (upper side in FIG. 2B),
A rear end inclined surface 6c is formed so as to extend toward the commutator 3 side toward the non-opposing side axial direction (upward in FIG. 2B), which is the axial direction on the side not facing the inclined surface 6a. or,
On the rear end side of the brush 6 excluding the rear end inclined surface 6c, one end of the pigtail 10 is embedded so as to project from the upper surface (the upper surface in FIGS. 2A and 2B). The other end of the pigtail 10 is connected to a control device (power supply device) (not shown) outside the DC motor 1.

The coil spring 7 is housed in the brush holder 5 so as to be supported by the rear end wall 5c, and the rear end inclined surface 6c of the brush 6 is housed in contact with the coil spring 7. Retained. At this time, as shown in FIG. 2A, the perfect circular rod 9 is arranged so that a part thereof enters the inside of the V-shaped groove 6 b of the brush 6.

The dimensions of each member are set so that the coil spring 7 is compressed in the radial direction of the commutator 3 when the brush 6 and the coil spring 7 are assembled. Therefore, the brush 6 is biased toward the commutator 3 side by the biasing force of the coil spring 7, and is in the axial direction on the side facing the inclined surface 6a by the component force of the coil spring 7 by the rear end inclined surface 6c. Opposite side axial direction (Fig. 2
(A), (b), downward). Therefore, the tip of the brush 6 is pressed into contact with the commutator 3.

Further, in the brush 6, when the inclined surface 6a is engaged with the true circular rod 9 in the axial direction of the commutator 3, the other side surface of the brush 6 opposite to the inclined surface 6a (V-shaped groove 6b) is opposed. It is moved and arranged in the opposite axial direction (downward in FIGS. 2A and 2B) until it comes into contact with the rotation direction side wall 5b. Before the brush 6 comes into contact with the other side wall 5b on the rotational direction side opposite to the side surface on the opposite side of the inclined surface 6a (V-shaped groove 6b), the brush 6 is prevented from coming into contact with the lower portion 5e of the brush holder 5. The axial length of the commutator 3 is set. As a result, in the brush 6, the inclined surface 6a is pressed and contacted with the perfect circular rod 9 in the rotation direction of the commutator 3, and
The side surface on the opposite side of the inclined surface 6a (V-shaped groove 6b) is pressed into contact with the other side wall 5b on the opposite side in the rotating direction.

In the DC motor 1 (brush device 4) configured as described above, since the brush 6 is in sliding contact with the commutator 3, the brush 6 and the commutator 3 are controlled by 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).

Even when the brush 6 is heated to a high temperature and expands with respect to the brush holder 5 when the rotor is rotated for a long time, the brush 6 is in the axial direction on the non-opposing side (in FIGS. 2A and 2B, By moving the upper side), the pair of side walls 5a and 5b on the rotation direction side including the perfect circular rod 9 will not be pinched.

Next, the characteristic effects of the above embodiment will be described below. (1) In the brush 6, the inclined surface 6a is pressed and contacted with the perfect circular rod 9 in the rotation direction of the commutator 3, and the inclined surface 6a
The side surface on the opposite side of the (V-shaped groove 6b) is pressed into contact with the other side wall 5b on the rotational direction side that faces the side surface. Therefore, for example, rattling of the brush 6 in the rotation direction of the commutator 3 is suppressed when the commutator 3 starts rotating (during start-up) or during rotation of the commutator 3. As a result, the contact area between the tip of the brush 6 and the commutator 3 is always maintained, and the supply of the drive current to the rotor, specifically, the winding wound around the armature core (not shown) is maintained. Therefore, in this DC motor 1, it is possible to obtain a desired rotation characteristic especially at the time of starting. Further, the generation of noise due to the vibration of the brush 6 is reduced.

Moreover, for example, even when the brush 6 becomes hot and expands with respect to the brush holder 5, the brush 6 moves in the axial direction on the non-opposing side (upward in FIGS. 2A and 2B). , A pair of side walls 5a, 5b in the direction of rotation including the perfect circular rod 9
There is no need to be pinched. Therefore, the movement of the brush 6 in the front-rear direction is prevented from being obstructed by the brush holder 5.

(2) The inclined surface 6a is one of the V-shaped grooves 6b formed on the side surface of the brush 6 (upper side in FIG. 2 (a)).
Space (arrangement space) in which the round bar 9 engaging with the inclined surface 6a enters the inside of the V-shaped groove 6b because it is the bottom surface of
Is ensured, and the inclined surface 6a can be easily formed.

(3) Since the true circular rod 9 having a convex curved portion on the side of the inclined surface 6a is used as the engaging portion for engaging the inclined surface 6a, the brush 6 can be inclined on the side of the true circular rod 9a. Is acceptable. Therefore, the brush 6 does not rattle in the rotation direction of the commutator 3 even if the precision of each component is not high, because the opposite side surface of the inclined surface 6a makes surface contact with the opposite side wall 5b on the rotation direction side. Suppressed.

(4) Rear end of brush 6 (commutator 3
The outer end in the radial direction of the rear end), which is closer to the commutator 3 side in the axial direction on the non-opposing side (upper side in FIGS. 2A and 2B), which is the axial direction on the side not facing the inclined surface 6a. An inclined surface 6c is formed, and a coil spring 7 that contacts the rear end inclined surface 6c and urges the commutator 3 side is provided behind the brush 6. Therefore, the brush 6 is biased toward the commutator 3 side by the biasing force of the coil spring 7, and is in the axial direction on the side facing the inclined surface 6a by the component force of the coil spring 7 by the rear end inclined surface 6c. It is urged in the opposite axial direction (downward in FIGS. 2A and 2B). With this configuration, the coil spring 7 also serves as the biasing means in the two directions, so that the number of parts of the brush device 4 can be reduced.

The above embodiment may be modified as follows. In the above embodiment, one (clockwise direction) side wall 5 a on the rotation direction side is provided on the inner side of the brush holder 5,
Although the perfect circular rod 9 serving as the engaging portion and the bending portion is fixed, another engaging portion may be used as long as the inclined surface 6a of the brush 6 is engaged with the commutator 3 in the axial direction.

For example, as shown in FIG. 3, the inclined surface 6a is formed on one side wall 21a of the brush holder 21 on the rotational direction side.
Protruding in a semi-circular shape to the side, the inclined surface 6a and the commutator 3
The semicircular convex portion 21b as an engaging portion and a curved portion that engages in the axial direction may be formed. Even with this,
It is possible to obtain the same effect as that of the above-described embodiment.

Further, for example, on one side wall 5a on the rotational direction side, the inner surface of the brush holder 5 is engaged with the inclined surface 6a, and no convex curved portion is formed on the inclined surface 6a side (for example,
You may implement by forming the engaging part of a convex part etc. which have an inclined surface along the inclined surface 6a. Even in this case, the same effects as the effects (1), (2), and (4) of the above-described embodiment can be obtained.

In the above embodiment, the V-shaped groove 6b is formed on one side surface of the brush 6, and the bottom surface above the V-shaped groove 6b (upper side in FIG. 2A) is the inclined surface 6a. However, as long as an inclined surface similar to the inclined surface 6a inclined with respect to the axial direction of the commutator 3 is formed on one side surface of the brush 6, the brush may be changed to another shape. For example, the brush may be changed to one side surface in which a groove having an inclined surface similar to the inclined surface 6a and a plane parallel to the upper surface of the brush is formed. In this case, it is necessary to change the shape of the perfect circular rod 9 (engagement portion) or the like as appropriate. Even in this case, the same effects as the effects (1) and (4) of the above embodiment can be obtained.

In the above embodiment, the rear end inclined surface 6c is formed at the rear end portion of the brush 6, and the coil spring 7 abutting against the rear end inclined surface 6c is provided behind the brush 6, thereby 6 is urged toward the commutator 3 side by the urging force of the coil spring 7, and the opposing side axial direction which is the axial direction of the side facing the inclined surface 6a by the component force of the coil spring 7 by the rear end inclined surface 6c. (Fig. 2 (a) (b)
Although it is assumed that the brush 6 is biased in the middle and the downward direction), another configuration may be used as long as the brush 6 can be biased in the two directions. For example, a first urging unit that urges the brush 6 toward the commutator 3 and the opposing side axial direction that is the axial direction of the side where the brush 6 faces the inclined surface 6a (see FIGS. 2A and 2B). ,
The second urging means for urging downward) may be separately provided. Even in this case, the same effects as the effects (1) to (3) of the above embodiment can be obtained.

In the above embodiment, the brush holder 5
Is integrally formed on a substrate 8 made of a resin material and fixed to a motor case (not shown). One side wall in the rotation direction is provided with an inclined surface 6a and an engaging portion for engaging the commutator 3 in the axial direction. If so, the brush holder may be configured with other members. For example, it may be composed of a resin substrate and a metal holder member fixed on the substrate. Even in this case, the same effect as that of the above-described embodiment can be obtained.

In the above embodiment, the coil spring 7 is used as the biasing means, but other biasing means (for example,
A torsion spring, etc.) may be used instead. Even in this case, the same effect as that of the above-described embodiment can be obtained.

In the above embodiment, the DC motor 1 having a pair (two) of the brush devices 4 is embodied, but a DC motor having another number (for example, three) of the brush devices 4 (for example, a wiper motor). Etc.). Even in this case, the same effect as that of the above-described embodiment can be obtained.

The technical ideas that can be understood from the above-described embodiment will be described below along with their effects. (A) The brush device according to claim 6, wherein the biasing means is a coil spring. With this arrangement, the brush is urged toward the commutator by the urging force of the coil spring, and the opposing side in the axial direction on the side facing the inclined surface by the component force of the coil spring by the rear end inclined surface. It is axially biased.

(B) A motor provided with the brush device according to any one of claims 1 to 6 and (a). With this configuration, it is possible to provide a motor that can prevent the brush from rattling with respect to the brush holder in the rotation direction of the commutator.

[0044]

As described in detail above, according to the present invention,
A brush device that can prevent the brush from rattling with respect to the brush holder in the rotation direction of the commutator can be provided.

[Brief description of drawings]

FIG. 1 is a schematic view of the brush device according to the present embodiment as viewed from the direction of a rotation axis.

FIG. 2A is a schematic view of the brush device according to the present embodiment as viewed from the commutator side. (B) The schematic diagram which looked at the same brush apparatus from the side.

FIG. 3 is a schematic view of another example brush device as viewed from the commutator side.

FIG. 4 is a schematic view of a conventional brush device as viewed from the direction of the rotation axis.

[Explanation of symbols]

3 ... Commutator, 5, 21 ... Brush holder, 6 ... Brush, 7 ... Coil spring (biasing means), 9 ... Round bar (engaging portion and bending portion), 6a ... Inclined surface, 6b ... V-shaped groove,
Reference numeral 6c ... Rear end inclined surface, 5a, 5b, 21a ... Rotation direction side wall, 21b ... Semicircular convex portion (engaging portion and curved portion).

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Seiya Yokoyama             Asumo Corporation, 390 Umeda, Kosai City, Shizuoka Prefecture             In the company (72) Inventor Moriya Kazuma             Asumo Corporation, 390 Umeda, Kosai City, Shizuoka Prefecture             In the company F-term (reference) 5H613 AA01 AA03 BB04 BB27 GA04                       GA10 GA11 GA13 GA15 KK05                       PP02

Claims (6)

[Claims] 1. A brush (6) is housed and held in a brush holder (5, 21) extending in the radial direction of the commutator (3), and a tip portion of the brush (6) is the commutator (3).
In the brush device that is pressed into contact with the brush (6), an inclined surface (6a) inclined to the axial direction of the commutator (3) is formed on one side surface of the commutator (3) in the rotation direction. , The pair of brushes (6) are arranged in parallel in the rotation direction of the commutator (3) by urging the brushes (6) in the axial direction on the opposite side, which is the axial direction on the side facing the inclined surface (6a). , 21) of the side walls (5a, 5b, 21a) on the rotation direction side forming part of the inclined surface (6a).
An engaging portion (9, 21b) that engages with the inclined surface (6a) and the commutator (3) in the axial direction is provided on the side of the one side wall (5a, 21a) in the direction of rotation that faces the side surface of the commutator (3). And brush device. 2. The brush device according to claim 1, wherein the inclined surface (6a) is one bottom surface of a V-shaped groove (6b) formed on a side surface of the brush (6). Brush device to do. 3. The brush device according to claim 1, wherein the engaging portion (9, 21b) is a convex curved portion on the side of the inclined surface (6a). . 4. The brush device according to claim 3, wherein the curved portion (9) is fixed to the one rotation direction side wall (5a) so as to project toward the inclined surface (6a). A brush device, which is a circular true bar. 5. The brush device according to claim 3, wherein the curved portion (21b) is a semicircular convex portion that protrudes in a semicircular shape toward the inclined surface (6a). . 6. The brush device according to claim 1, wherein a rear end portion of the brush (6) is not opposed to the inclined surface (6a) in the axial direction. A rear end inclined surface (6c) that is closer to the commutator (3) as it goes toward the lateral axis.
The rear end inclined surface (6) behind the brush (6).
A brush device comprising an urging means (7) which abuts against (c) and urges the commutator (3) side.