JP2003061296A - Brush apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a brush apparatus for inhibiting a brush from deviating in a rotary direction of a commutator to a brush holder. SOLUTION: In a brush apparatus 4, a brush 6 is accommodated and retained in a brush holder 5 that is extended in the radial direction of a commutator while the brush 6 has a gap, and the tip section of the brush 6 is pressed and brought into contact with the commutator 3. An accommodation recess 6a that is extended from the rear end section to the tip side is formed at the brush 6. A leaf spring 8 that is inserted into the accommodation recess 6a and presses an inner wall 6a in the rotary direction of the commutator at the accommodation recess 6a is provided at a rear end wall 5c 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, a brush holder is accommodated and held in a brush holder extending in the radial direction of the commutator with a gap, and the tip of the brush is pressed against the commutator. In the brush device to be contacted, the brush is provided with an accommodating portion extending from the rear end portion to the tip end side, and the brush holder is provided with a pressing member that is inserted into the accommodating portion and presses an inner wall of the accommodating portion. .

According to a second aspect of the present invention, in the brush device according to the first aspect, the pressing member presses an inner wall of the commutator in the accommodating portion in a rotational direction, thereby moving the brush into the brush holder. Is pressed against the side wall of the commutator in the rotation direction.

According to a third aspect of the present invention, in the brush device according to the first aspect, the pressing member presses the axial inner wall of the commutator in the accommodating portion to move the brush into the brush holder. Is pressed against the inner wall of the commutator in the axial direction.

The invention according to claim 4 is the invention according to claim 2 or 3.
In the brush device according to the item (1), a plurality of the pressing members are provided. The invention according to claim 5 is the brush device according to claim 1, wherein a plurality of the pressing members are provided,
The brushes were provided so as to be pressed in different directions and held inside.

The invention according to a sixth aspect is the first to fifth aspects.
The brush device according to any one of claims 1 to 3, wherein the biasing means for pressing the tip of the brush into contact with the commutator is a coil spring that contacts and biases the rear end of the brush. The member was arranged so as to penetrate through the inside of the coil spring.

The invention according to claim 7 is the same as claims 1 to 6.
In the brush device according to any one of items 1 to 3, a drive current is supplied to the brush via the pressing member. (Operation) According to the invention of claim 1, the brush has:
An accommodating portion extending from the rear end portion to the tip side is formed, and the brush holder is provided with a pressing member that is inserted into the accommodating portion and presses the inner wall of the accommodating portion. Therefore, the brush is pressed in either direction, for example, by the brush holder. This prevents the brush from rattling with respect to the brush holder in the rotation direction of the commutator.

According to the second aspect of the present invention, the pressing member presses the inner wall of the commutator in the rotation direction of the accommodating portion, so that the brush moves in the rotation direction of the commutator in the brush holder. Pressed against the side wall. This prevents the brush from rattling with respect to the brush holder in the rotation direction of the commutator.

According to the third aspect of the invention, the pressing member presses the axial inner wall of the commutator in the accommodating portion, so that the brush moves in the axial direction of the commutator in the brush holder. It is pressed against the inner side wall. Therefore, due to the frictional force between the brush and the inner wall in the axial direction,
The brush is prevented from rattling with respect to the brush holder in the rotation direction of the commutator.

According to the invention as set forth in claim 4, since a plurality of pressing members are provided, the brush can be pressed in a well-balanced manner. According to the invention described in claim 5, a plurality of pressing members are provided and are provided so as to press in different directions and hold the brush inside. Therefore, the brush is prevented from rattling with respect to the brush holder in the rotation direction of the commutator.

According to the sixth aspect of the present invention, the urging means for pressing the tip end of the brush to the commutator is a coil spring for abutting and urging the rear end of the brush. The pressing member is arranged so as to penetrate the inside of the coil spring. Therefore, it is not necessary to specially provide a space for disposing the pressing member, and the device does not become large.

According to the invention described in claim 7, the drive current is supplied to the brush through the pressing member that presses the inner wall of the accommodating portion of the brush, that is, presses the inner wall.
Therefore, it is not necessary to provide a pigtail or the like on the brush.

[0019]

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 a rotating shaft 2, a substantially cylindrical commutator (commutator) 3 fixed to the rotating 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.
And a leaf spring 8 as a pressing member.

The brush holder 5 is made of a resin material and is integrally formed on a substrate 9 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.
2a, 5b, a rear end wall 5c formed so as to connect the rear end sides of the pair of rotation direction side side walls 5a, 5b (radially outer side of the commutator 3), as shown in FIGS. In addition, it is composed of an upper part 5d and a lower part 5e (formed of a part of the substrate 9) and the like formed so as to cover the upper end and the lower end of the pair of rotation direction side walls 5a and 5b. The rear end wall 5c of the brush holder 5 extends in the radial direction of the commutator 3 inside the brush holder 5 and is curved in an S shape (inverse S shape) when viewed from the axial direction of the commutator 3 (see FIG. 1). The leaf spring 8 is fixed. 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. The brush 6 is formed with an accommodating recess 6a extending from a rear end portion (radially outer end portion of the commutator 3) toward a tip end portion side (commutator 3 side). The accommodation recess 6a of the present embodiment has an inner wall formed in a quadrangle when viewed in the radial direction of the commutator 3 (see FIG. 2A). The size of the accommodating recess 6a is set to have a gap in the vertical and horizontal directions (axial direction and rotation direction of the commutator 3) when the tip end side of the leaf spring 8 is inserted. or,
The housing recess 6 a of the present embodiment is formed near the lower part of the brush 6.

The coil spring 7 is housed in the brush holder 5 so as to be supported by the rear end wall 5c, and the brush 6 is housed and held in contact with the coil spring 7. Here, in consideration of thermal expansion of the brush 6 to be housed, the distance between the pair of rotation-side side walls 5a and 5b is set so that the brush 6 is housed when the brush 6 in a cold state (normal temperature) is housed. It is set to have a gap between them.

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 rear end of the brush 6 is biased toward the commutator 3 by the coil spring 7, and the tip of the brush 6 is pressed into contact with the commutator 3. Further, the leaf spring 8 is arranged so that the base end side thereof penetrates the inside of the coil spring 7. Further, the leaf spring 8 is inserted into the accommodation recess 6 a of the brush 6 at its tip end side, and the accommodation recess 6 a
The inner wall of a is pressed. Specifically, the leaf spring 8 is an inner wall 6b of the housing recess 6a in the rotating direction of the commutator 3.
By pressing, the brush 6 is pressed against the side wall 5a on the rotational direction side.

As shown in FIGS. 2A and 2B, one end of a pigtail 10 is embedded in the brush 6, and the pigtail is connected to a control device (power supply device) (not shown) outside the DC motor 1. It

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 rotation-side side walls 5a and 5b of the brush holder 5 is set so as to have a gap with the brush 6 when the brush 6 in a cold state (normal temperature) is accommodated. Therefore, the brush holder 5 is prevented from obstructing the movement of the brush 6 in the front-rear direction even when 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 is pressed against the rotation direction side wall 5a of the brush holder 5 by the leaf spring 8 pressing the inner wall 6b of the commutator 3 in the rotation direction of the accommodation recess 6a. Therefore, for example, when the commutator 3 starts rotating (at start-up), during rotation of the commutator 3, or the like,
The brush 6 is prevented from rattling in the rotation direction 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. or,
Generation of noise due to vibration of the brush 6 is reduced.

(2) Connect the tip of the brush 6 to the commutator 3
A coil spring 7 that abuts against the rear end portion of the brush 6 to urge it is used as the urging means for pressing and contacting with the plate spring 8. The leaf spring 8 is arranged so as to penetrate the inside of the coil spring 7. Therefore, it is not necessary to specially provide a space for disposing the leaf spring 8, and the device does not become large.

The above embodiment may be modified as follows. In the above-described embodiment, the brush 6 is provided with one accommodating recess 6a and the brush holder 5 (rear end wall 5c) with one leaf spring 8. However, the accommodating recess 6a and the plate are not included. The number of springs 8 may be appropriately changed and implemented.

For example, as shown in FIGS. 3 (a) and 3 (b),
It is also possible to form a brush device 23 in which two accommodation recesses 21a are formed in the brush 21 and two leaf springs 22 corresponding to each accommodation recess 21a are provided in the brush holder 5 (rear end wall 5c). Specifically, the brush 21 is formed with two accommodating recesses 21 a extending in the axial direction of the commutator 3 from the rear end (the radially outer end of the commutator 3) to the tip (commutator 3 side). . The rear end wall 5c of the brush holder 5 extends in the radial direction of the commutator 3 inside the brush holder 5 and is similar to the leaf spring 8 (see FIG. 1) of the above embodiment when viewed from the axial direction of the commutator 3. The leaf spring 22 curved in the S shape (reverse S shape) of the commutator 3
The two are fixed side by side in the axial direction. The width of each leaf spring 22 in the axial direction of the commutator 3 is set smaller than the width of the leaf spring 8 of the above-described embodiment. Then, each leaf spring 22 presses the inner wall 21b in the rotation direction of the commutator 3 in the accommodation recess 21a to press the brush 21 against the side wall 5a in the rotation direction. With the brush device 23 thus configured, the same effects as those of the above-described embodiment can be obtained. Moreover, since the two leaf springs 22 are provided side by side in the axial direction of the commutator 3, it is possible to press the brush 21 (in the axial direction of the commutator 3) with good balance. Therefore, rattling of the brush 6 with respect to the brush holder 5 is further suppressed. In this example, the brush 21 has a housing recess 21.
Although two a are formed, of course, one large accommodating recess elongated in the axial direction may be formed, and two leaf springs 22 may be inserted into the accommodating recess.

In the above-described embodiment, the leaf spring 8 has the inner wall 6b in the accommodation recess 6a in the rotating direction of the commutator 3.
Although the brush 6 is pressed against the side wall 5a in the rotational direction by pressing, it may be provided so as to press the inner wall of the accommodation recess (accommodation portion) in the other direction.

For example, as shown in FIGS. 4 (a) and 4 (b),
The leaf spring 31 presses the inner wall 32b of the commutator 3 in the housing recess 32a of the brush 32 in the axial direction (lower side), so that the lower portion 5e of the brush holder 5 serving as the inner wall of the commutator 3 in the axial direction. You may change so that it may press. Specifically, the brush 32 has
A housing recess 32a is formed which extends from the rear end portion (radially outer end portion of the commutator 3) to the front end portion side (commutator 3 side). The rear end wall 5c of the brush holder 5 extends in the radial direction of the commutator 3 inside the brush holder 5 and has an S-shape when viewed from the direction perpendicular to the side walls 5a and 5b on the rotation direction side (see FIG. 4B). A leaf spring 31 curved in an (inverted S shape) is fixed. And the leaf spring 31
Presses the inner wall 32b of the commutator 3 in the accommodation recess 32a in the axial direction (lower side), so that the brush 32
Is pressed against the lower portion 5e. In the brush device 33 thus configured, the brush 32 and the lower portion 5 of the brush holder 5 are
The frictional force of e prevents the brush 32 from rattling with respect to the brush holder 5 in the rotation direction of the commutator 3. Further, the same effect as the effect (2) of the above embodiment can be obtained.

In the above embodiments, the leaf springs 8 and 2 are
2 and 31 are provided so as to press the brushes 6, 21 and 32 against the rotation direction side wall 5a and the lower portion 5e of the brush holder 5, but a plurality of leaf springs (pressing members) are provided and pressed in different directions. Then, the brush may be provided so as to be held inside. The term "holding" as used herein means that the leaf spring (pressing member) does not have to be actually held, and a force is applied in the holding direction.

For example, as shown in FIGS.
Two accommodating recesses 41a and 41b are formed in the brush 41, and leaf springs 42 and 43 are inserted into the accommodating recesses 41a and 41b, respectively, so that the brush 41 is held internally by the leaf springs 42 and 43. You may arrange. Specifically, the brush 41
At the rear end (the radially outer end of the commutator 3)
Accommodating recessed portion 4 extending from the end to the tip side (commutator 3 side)
Two 1a and 41b are formed side by side in the axial direction of the commutator 3. The rear end wall 5c of the brush holder 5 extends in the radial direction of the commutator 3 inside the brush holder 5 and is S-shaped when viewed from the vertical direction of the side walls 5a and 5b on the rotation direction side (see FIG. 5B). Two leaf springs 42, 43 curved in an (inverted S shape) are fixed side by side in the axial direction of the commutator 3. The two leaf springs 42 and 43 are provided at a distance smaller than the distance between the two accommodation recesses 41a and 41b. Therefore, above (FIGS. 5A and 5B)
The middle and upper leaf springs 42 press the lower inner wall 41c of the upper accommodation recess 41a, and the lower (in FIGS. 5A and 5B),
The leaf spring 43 on the lower side presses the inner wall 41d on the upper side of the housing recess 41b on the lower side.
Applies a force to hold the brush 41 inside.
In the brush device 44 thus configured, the brush 41
Since the force is applied by the leaf springs 42 and 43 so as to be clamped inside, the brush 41 is prevented from rattling with respect to the brush holder 5 in the rotation direction of the commutator 3. Further, the same effect as the effect (2) of the above embodiment can be obtained.

Further, for example, two leaf springs (pressing members) are inserted into the accommodating recess of the brush, one leaf spring presses one inner wall of the accommodating recess, and the other leaf spring of the other accommodating recess. The brush may be held inside by pressing the inner wall, that is, by pressing in the direction in which the leaf springs are separated from each other. Even with this, the brush 4
The rattling of 1 with respect to the brush holder 5 in the rotation direction of the commutator 3 is suppressed.

The brushes 6, 21, 3 of the above-mentioned respective embodiments
Although it is assumed that one ends of the pigtails 10 are embedded in the reference numerals 2 and 41 and a drive current is supplied via the pigtails 10, the leaf springs (pressing members) 8, 22, 31, 42, 4 are described.
The drive current may be supplied via the switch 3.

For example, as shown in FIG. 6, a lead wire connected to an external control device (power supply device) (not shown) at the base end portion of the leaf spring 42 of the other example (see FIGS. 5A and 5B). You may implement by connecting 45. With this, brush 4
The brush 4 presses the inner wall 41c of the first housing recess 41a, that is, through the leaf spring 42 pressed against the inner wall 41c.
The drive current is supplied to the drive circuit 1. Therefore, it is not necessary to provide the brush 41 with a pigtail or the like. As a result, the indeterminate vibration that occurs when the pigtail is provided on the brush is eliminated. In this example, the conductor wire 45 is connected to the leaf spring 42, but it goes without saying that the conductor wire 45 may be changed to another conductor, for example, a terminal (terminal) formed by a sheet metal press.

In the above embodiments, the brushes 6 and 2 are used.
Housing recesses 6a, 21 serving as housings in 1, 32, 41
Although a, 32a, 41a, 41b are formed, the housing recess may be replaced by a housing hole serving as a housing portion penetrating from the rear end portion to the tip portion of the brush.

In the above embodiments, the leaf springs 8, 22, 31, 42, 43 are used as the pressing members, but similarly, the inner walls 6b, 21b, 32b of the housing recesses 6a, 21a, 32a, 41a, 41b are also used. , 41c, 41d may be changed to another pressing member, for example, a torsion coil spring or the like.

In each of the above embodiments, the coil spring 7 is used as the urging means, but the brushes 6 and 2 are similarly used.
If it is possible to urge 1, 32, 41, other urging means, for example, a torsion coil spring or the like may be used instead.

In each of the above embodiments, 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 wiper, for example) Motor) and the like. 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 any one of claims 1 to 7, wherein the housing portion is a housing recess or a housing hole. With this configuration, since the housing portion is the housing recess or the housing hole, it can be easily formed.

(B) The brush device according to any one of claims 1 to 7 and (a), wherein the pressing member is a leaf spring. With this configuration, the inner wall of the accommodating portion can be pressed with a simple structure.

(C) In the brush device according to the fifth aspect, a plurality of the accommodating portions are provided, the pressing members are inserted into the respective accommodating portions, and the brushes are arranged so as to be sandwiched inside. Brush device characterized by. With this configuration, the pressing member is inserted into each of the plurality of accommodating portions, and is arranged so as to sandwich the brush inside. Therefore, the brush is prevented from rattling with respect to the brush holder in the rotation direction of the commutator.

(D) Claims 1 to 7 and (a) to
A motor provided with the brush device according to any one of (C).
With this configuration, it is possible to provide a motor that can prevent the brush from rattling with respect to the brush holder.

[0047]

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. 3A is a schematic view of another example brush device as viewed from the commutator side. (B) The schematic diagram which looked at the same brush apparatus from the side.

FIG. 4A is a schematic view of another example of the brush device as viewed from the commutator side. (B) The schematic diagram which looked at the same brush apparatus from the side.

FIG. 5A is a schematic view of another example brush device as viewed from the commutator side. (B) The schematic diagram which looked at the same brush apparatus from the side.

FIG. 6 is a schematic view of a brush device of another example as viewed from the side.

FIG. 7 is a schematic view of a conventional brush device as viewed from the direction of the rotation axis.

[Explanation of symbols]

3 ... Commutator, 5 ... Brush holder, 6, 21, 3
2, 41 ... Brush, 7 ... Coil spring, 8, 22,
31, 42, 43 ... Leaf spring (pressing member), 5a ... Rotation direction side wall, 5e ... Lower part (axial direction side inner wall), 6a, 21
a, 32a, 41a, 41b ... Accommodation recess (accommodation portion), 6
b, 21b, 32b, 41c, 41d ... Inner wall.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Moriya Kazuma             Asumo Corporation, 390 Umeda, Kosai City, Shizuoka Prefecture             In the company (72) Inventor Yasuhide Ito             Asumo Corporation, 390 Umeda, Kosai City, Shizuoka Prefecture             In the company F term (reference) 5H605 AA05 BB05 CC07 EA11 EA26                       EA30                 5H613 BB15 BB27 BB29 GA16 KK02                       KK17

Claims (7)

[Claims] 1. Brushes (6, 21, 32, 41) in a brush holder (5) extending in the radial direction of the commutator (3).
Are accommodated and held with a gap, and the brush (6, 2
In the brush device in which the tip end portion of (1, 32, 41) is in pressure contact with the commutator (3), the brush (6, 21, 32, 41) is provided with an accommodating portion (6a, extending from the rear end portion to the tip end side). 21a, 32a, 41
a, 41b), and the accommodating portion (6a, 21a) in the brush holder (5).
a, 32a, 41a, 41b), and the inner wall (6) of the accommodating portion (6a, 21a, 32a, 41a, 41b).
b, 21b, 32b, 41c, 41d) is provided with a pressing member (8, 22, 31, 42, 43). 2. The brush device according to claim 1, wherein the pressing member (8, 22) is provided in the housing portion (6a, 21).
By pressing the inner walls (6b, 21b) of the commutator (3) in the rotational direction in a), the brushes (6, 2) are pressed.
1. A brush device, wherein 1) is pressed against a rotation direction side wall (5a) of the commutator (3) in the brush holder (5). 3. The brush device according to claim 1, wherein the pressing member (31) presses an axial inner wall (32b) of the commutator (3) in the accommodation portion (32a), A brush device, characterized in that the brush (32) is pressed against the axially inner wall (5e) of the commutator (3) in the brush holder (5). 4. The brush device according to claim 2, wherein a plurality of the pressing members (22) are provided. 5. The brush device according to claim 1, wherein a plurality of the pressing members (42, 43) are provided, and
A brush device, characterized in that the brush (41) is provided so as to be held inside by pressing in different directions. 6. The brush device according to any one of claims 1 to 5, wherein the tip of the brush (6, 21, 32, 41) is pressed against the commutator (3) to urge it. Means
A coil spring (7) that abuts and urges the rear end of the brush (6, 21, 32, 41), and the pressing member (8, 22, 31, 42, 43) is the coil spring (7). ) Is arranged so as to penetrate the inside of the brush device. 7. The brush device according to claim 1, wherein a driving current is supplied to the brush (41) via the pressing member (42). Brush device.