JPH11299183A - Brush sliding touching apparatus and abutting material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce vibration and in its turn to prevent noise generation at a sliding touching time. SOLUTION: A brush sliding touching apparatus is provided with a commutator 2 which is integrated with the shaft 1 of a motor and rotates together, a power feeding substance 3 which is brought into contact with the commutator 2 and slides on it, a holder 7 having a wall 7b in the direction of rotation of the commutator 2 for holding the power feeding substance 3 in the direction of rotation of the commutator 2, and a coil spring 8 for pushing the power feeding substance 3 to the commutator 2 side. The power feeding substance 3 is provided with a brush to be brought into direct contact with the commutator 2, a coupling substance 5 united to the brush 4 and having elastic and damping properties, and a weight 6 to be united to the coupling substance 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brush sliding device for sliding a contact member provided with a brush to a commutator of a motor, and more particularly to a structure of the contact member.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 11, a commutator (rotating body) 52 is provided on a rotating shaft 51 of a DC motor, and a power supply brush (contact member) 53 is brought into contact with the commutator 52. ing. The brush 53 is housed in a brush holder 54 formed in, for example, a motor housing or the like, and is pressed and held by the spring 55 toward the commutator 52. The brush 53 thus held is in sliding contact with the outer peripheral surface of the commutator 52 even while the commutator 52 is rotating. Therefore, in this DC motor, drive power can be supplied to the coil (not shown) that rotates integrally with the rotating shaft 51 via the brush 53 and the commutator 52.

[0003]

By the way, during the rotation of the commutator 52, the brush 53 is rotated by the sliding resistance generated between the commutator 52 and the brush 53 in the direction of rotation of the commutator 52 (indicated by an arrow A in the figure). Direction), and is pressed against one wall surface 54a of the brush holder 54 located in the direction (i.e., direction), and slidably contacts the commutator 52 in that state.
The brush 53 is generally formed of a mixture of graphite and copper, and it is known that when the humidity in the air decreases, the sliding resistance increases. Therefore, for example, when the humidity in the air decreases and the sliding resistance increases, the brush 53
Is increased against the one wall surface 54a.
Then, the tip 53a of the brush 53 is pulled in so as to enter between the wall surface 54a and the commutator 52, and the one wall surface 54a is elastically deformed in the rotation direction of the commutator 52. Then, a force for returning the one wall surface 54a to the original shape acts on the brush 53, and the brush 53 is repelled to the same wall surface 54a. Then, such a continuous operation causes the brush 53 to vibrate in the brush holder 54, which causes a problem that noise generally called chirp sound is generated.

An object of the present invention is to provide a brush sliding device for sliding a contact member provided with a brush to a commutator, in which vibration at the time of the sliding contact can be reduced, thereby preventing the generation of noise. The present invention is to provide a brush sliding device and an abutting member that can perform the above.

[0005]

According to a first aspect of the present invention, there is provided a commutator rotating integrally with a rotating shaft of a motor, a contact member slidably contacting the commutator, and rotating the contact member by rotating the commutator. In order to hold in the direction, in a brush sliding contact device provided with a holder having a wall surface in the rotation direction of the commutator, and a biasing means for biasing the contact member toward the commutator, the contact member, The gist of the present invention includes a brush that is in direct contact with the rotating body, and a vibration suppression unit that cancels the vibration of the brush that occurs when the brush slides on the rotating body.

According to a second aspect of the present invention, in the brush sliding device according to the first aspect, the vibration suppressing portion is connected to the brush and has a coupling portion having elasticity and damping characteristics; And a weight connected to the weight.

[0007] The invention described in claim 3 is the first or second invention.
Wherein the urging means is a coil spring that urges the brush from the side opposite to the commutator side, and wherein the vibration suppressing portion is disposed inside the coil spring. Make a summary.

[0008] The invention described in claim 4 is the invention according to claim 2 or 3.
In the brush sliding contact device according to the above, the connecting portion is formed by a rubber tube. According to a fifth aspect of the present invention, the holder is held in the rotating direction of the commutator by a holder having a wall surface in the rotating direction of the commutator, and is urged by the urging means toward the commutator to be in sliding contact with the rotating body. The gist of the contact member is to include a brush directly in contact with the commutator, and a vibration suppressing portion for canceling vibration of the brush generated when the brush slides on the commutator.

According to the first and fifth aspects of the present invention, the contact member that has slidably contacted the commutator is pressed against the wall surface of the holder by the sliding resistance between the commutator and the brush.
Then, for example, when the tip of the brush is pulled in so as to enter between the wall and the commutator, and the wall of the holder is deformed by the brush, a force to return the wall to its original position acts on the brush, The brush will be bounced off the wall. Then, the repelled brush is displaced in the rotation direction of the commutator by the sliding resistance force, and is again pressed against the wall surface of the holder. Therefore, the brush vibrates. At this time, the vibration suppressing portion provided in the contact member cancels the vibration, so that the vibration of the brush is reduced.

According to the second aspect of the present invention, for example, when the tip of the brush is pulled in so as to enter between the wall surface of the holder and the rotating body and the wall surface of the holder is deformed by the brush, The force that the wall tries to return works on the brush, and the brush is repelled to the wall. At this time, the displacing force of the brush tries to displace the weight portion via the connecting portion, but is not transmitted instantaneously but transmitted slightly later due to the elasticity and damping characteristics of the connecting portion. When the weight is displaced, the brush is displaced in the rotational direction of the commutator by the sliding resistance. Therefore, the displacement of the brush, that is, the vibration, interferes with the displacement of the weight portion and is substantially offset. As a result, with this brush sliding device,
Vibration when the brush is in sliding contact can be reduced.

According to the third aspect of the present invention, the urging means is a coil spring, and the vibration suppressing portion is disposed inside the coil spring. There is no.

According to the fourth aspect of the present invention, since the connecting portion is formed of a rubber tube, the connecting portion having elasticity and damping characteristics can be formed at low cost.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in a power supply brush sliding contact device will be described below with reference to FIGS.

As shown in FIG. 1, the rotating shaft 1 of the DC motor
Is provided with a commutator 2 for power supply, and the commutator 2 is in contact with a power supply 3 as a contact member. The power supply body 3 includes a power supply brush 4, a coupling body 5 as a coupling portion, and a weight 6 as a weight portion.
The brush 4 is made of a mixture of graphite and copper.
As shown in FIG. The weight 6 is
The brush 4 is connected and fixed to the base end face 4 a of the brush 4 via the coupling body 5. More specifically, a cylindrical convex portion 4b is formed on the base end surface 4a of the brush 4. The coupling body 5 is formed of a cylindrical rubber tube whose inner circumference circle corresponds to the projection 4b. The coupling body 5 is not limited to a rubber tube, but may be rubber or a polymer having viscosity and elasticity corresponding thereto. The weight 6 is made of metal. Weight 6
Is formed in a substantially columnar shape, and the convex portion 4 is provided on one end surface thereof.
A protrusion 6a having the same shape as b is formed. Then, the protrusion 4 b of the brush 4 is fitted to one end of the combined body 5,
The brush 4 and the weight 6 are connected and fixed via the combination 5 by fitting the projection 6 a of the weight 6 to the other end of the combination 5. In the present embodiment, the combined body 5 and the weight 6 constitute a vibration suppressing unit.

FIG. 3 schematically shows the feeder 3 (the brush 4, the coupling body 5, and the weight 6). That is, in the present embodiment, the coupling body 5 includes the damping element 5a having a damping characteristic and the elastic deformation element 5 having elasticity.
b). In addition, the said damping characteristic is
When the coupling body 5 is deformed, that is, the brush 4
When the position is displaced, a reaction force proportional to the deformation (displacement) speed is generated.

The power supply 3 is accommodated in a brush holder 7 formed in a motor housing (not shown).
The brush holder 7 is formed in a box shape with a bottom and an open end face on the commutator 2 side. And the power supply 3
Is biased by a coil spring 8 as biasing means, one end of which is supported on a bottom surface 7a in the brush holder 7,
It is held in a state of being pressed against the commutator 2.
More specifically, the power supply body 3 has a base end surface 4 a of the brush 4 urged toward the commutator 2 by a coil spring 8,
The tip 4c of the commutator 2 protrudes from the opening end of the brush holder 7, and the tip 4d of the brush holder 7 is held in pressure contact with the commutator 2.

In the present embodiment, the coupling body 5 and the weight 6 are arranged inside the coil spring 8. In the present embodiment, the commutator 2, the power supply 3, the brush holder 7, and the coil spring 8 constitute a brush sliding device.

The feeder 3 held as described above comes into sliding contact with the commutator 2 while the commutator 2 is rotating. Therefore, in this DC motor, drive power can be supplied to the coil (not shown) that rotates integrally with the rotating shaft 1 via the brush 4 and the commutator 2. At this time, the power supply body 3 is pressed against one wall surface 7b of the brush holder 7 located in the rotation direction of the commutator 2 (the direction of the arrow A in the figure) due to the sliding resistance generated between the commutator 2 and the brush 4. In this state, it comes into sliding contact with the commutator 2.

Next, the characteristic operation and effect of the above embodiment will be described. (1) In the above embodiment, for example, when the humidity in the air decreases and the sliding resistance increases, the force with which the power supply 3 is pressed against the one wall surface 7b of the brush holder 7 increases. Then, the tip 4c of the brush 4 is pulled in so as to enter between the wall surface 7b and the commutator 2, and the one wall surface 7b is elastically deformed in the rotation direction of the commutator 2. Then, a force for returning the one wall surface 7b to the original shape acts on the brush 4, and the brush 4 is repelled to the same wall surface 7b. At this time, the displacing force of the brush 4 attempts to displace the weight 6 via the coupling body 5,
Due to the elasticity and damping characteristics of the transmission, the transmission is not instantaneous but transmitted with a slight delay. That is, when the brush 4 is displaced in the direction opposite to the rotation of the commutator 2 (the direction of the arrow B in the drawing), the weight 6 is displaced with a slight delay. When the weight 6 is displaced, the brush 4 is displaced in the rotational direction of the commutator 2 due to the sliding resistance. Therefore, brush 4
, Ie, the vibration, interferes with the displacement of the weight 6 and is substantially canceled. As a result, the vibration of the brush 4 in the brush holder 7 is reduced, and the generation of noise can be reduced.

(2) In the above embodiment, since the coupling body 5 and the weight body 6 are arranged inside the coil spring 8, the brush sliding device does not become large. (3) In the above embodiment, since the coupling body 5 is formed of the rubber tube, the coupling body 5 having elasticity and damping characteristics can be configured at low cost.

The above embodiment may be modified as follows. The power supply 3 of the above embodiment is connected to the brush 4 that is in direct contact with the commutator 2, connected to the brush 4, and connected to the connection (connection 5) having elasticity and damping characteristics, and connected to the connection. And any other weight portion (weight body 6), any shape, any arrangement, or any connection.

For example, the power supply 10 may be changed to that shown in FIG. The power supply 10 includes a brush 11, the combined body 5, the weight 6, and an embedded body 12. A concave portion 11b formed in a cylindrical shape is formed on a base end surface 11a of the brush 11. The embedded body 12
It is formed in a cylindrical shape, and is embedded and fixed in the concave portion 11b. Then, a brush 1 is attached to one end of the combined body 5.
The brush 4 and the weight 6 are connected to each other by fitting the embedded body 12 protruding from the base end face 11a of the first body 1 and the projection 6a of the weight body 6 at the other end of the combined body 5. It is connected and fixed through. Even in this case, the same effect as that of the above embodiment can be obtained.

Further, as shown in FIG. 5, the brush 11 may have an inclined base end face 11c. More specifically, the base end face 11c is inclined higher in the direction of rotation of the commutator 2 (in the direction of arrow A in the figure) and lower in the opposite direction. By doing so, the brush 11 whose base end face 11c is urged by the coil spring 8 is pressed by the commutator 2 and pressed against one wall surface 7b of the brush holder 7. Therefore, when the brush 11 is repelled to the wall surface 7b of the brush holder 7, the repelled amount is reduced. As described above, the displacement of the brush 11 interferes with the displacement of the weight 6 and is substantially offset, so that the vibration of the brush 11 in the brush holder 7 is further reduced.

For example, the power supply 20 may be changed to the one shown in FIG. The power supply body 20 includes a power supply brush 21,
And a connecting weight 22. Base end face 21 of brush 21
A is formed with a columnar projection 21b. The connecting weight 22 is made of rubber. Further, the connecting weight body 22 includes a cylindrical connecting portion 22a whose inner circumferential circle corresponds to the convex portion 21b,
And a weight portion 22b extending in a substantially cylindrical shape from one end of the coupling portion 22a. Then, the brush 21 and the connecting weight 2
2 is a protrusion 2 of the brush 21 at one end of the connecting portion 22a.
1b is connected and fixed by fitting.

In this way, the displacement force of the brush 21 tends to displace the weight portion 22b via the coupling portion 22a, but is not transmitted instantaneously due to the elasticity and damping characteristics of the coupling portion 22a. Is delayed. That is, when the brush 21 is displaced in the direction opposite to the rotation of the commutator 2 (the direction of the arrow B in the drawing), the weight portion 22b is displaced with a slight delay. When the weight 22b is displaced, the brush 21 causes the commutator 2 to move due to the sliding resistance.
In the direction of rotation. Therefore, the displacement of the brush 21, that is, the vibration, interferes with the displacement of the weight portion 22b and is substantially canceled.
As a result, the vibration of the brush 21 in the brush holder 7 is reduced, and the generation of noise can be reduced.

As shown in FIG. 7, the connecting weight body 22 may be provided with a metallic weight 23 having a specific gravity larger than that of rubber, for example, in a weight portion 22b. In this case, the weight portion 22b becomes heavier than the whole made of rubber. Therefore, the weight 22b can be made to have a weight corresponding to the frequency of the brush 21 without increasing the volume of the weight 22b. That is, without increasing the volume of the weight portion 22b, the displacement of the brush 21, that is, the vibration can be substantially offset by the displacement of the weight portion 22b.

For example, the power supply 30 may be changed as shown in FIG. The power supply body 30 includes a power supply brush 31,
And a connecting weight 32. Base face 31 of brush 31
A is formed with a concave portion 31b formed in a cylindrical shape. The connecting weight 32 is made of rubber. Also, the connecting weight 3
2 is a cylindrical fixing portion 32a corresponding to the concave portion 31b.
And a cylindrical fixed portion 32a having a smaller diameter than the fixed portion 32a.
And a weight 32c extending from the connecting portion 32b in a cylindrical shape having a larger diameter than the connecting portion 32b. The brush 31 and the connecting weight 32 are fixed by fitting a fixing portion 32a to the concave portion 31b.

With this arrangement, the displacement force of the brush 31 tends to displace the weight portion 32c via the coupling portion 32b, but is not transmitted instantaneously due to the elasticity and damping characteristics of the coupling portion 32b. Is delayed. Therefore, as described above, the displacement, that is, the vibration of the brush 31 is
Interference with the displacement of the weight portion 32c substantially cancels out. as a result,
Vibration of the brush 31 in the brush holder 7 is reduced, and thus noise generation can be reduced.

As shown in FIG. 9, the connecting weight 32 may be provided with a weight 33 made of, for example, a metal having a higher specific gravity than that of rubber in the weight 32c. In this case, the weight 32c becomes heavier than the whole made of rubber. Therefore, the weight 32c can be made to have a weight corresponding to the frequency of the brush 31 without increasing the volume of the weight 32c. That is, without increasing the volume of the weight 32c, the displacement of the brush 31, ie, the vibration, can be substantially offset by the displacement of the weight 32c.

In the above-described embodiment, the coupling portion (coupling member 5) and the weight portion (weight member 6) provided in the power feeding body 3 are arranged inside the coil spring 8, but are arranged inside the coil spring 8. It is not necessary. For example, as shown in FIG. 10, a through hole 7d may be provided in the bottom 7c of the brush holder 7, and the weight portion 22b of the coupling weight body 22 may be disposed so as to pass through the through hole 7d. Also in this case, the displacement of the brush 21, that is, the vibration can be substantially offset by the displacement of the weight portion 22b.

In the above-described embodiment, the coil spring 8 is used to bias the power supply 3 toward the commutator 2. However, for example, another biasing means such as a leaf spring is used to bias the power feeding body 3. Is also good.

The technical ideas other than the claims that can be grasped from the above embodiment will be described below together with their effects. (A) A motor provided with the brush sliding device according to any one of claims 1 to 4. With this configuration, the vibration when the brush is in sliding contact with the commutator can be reduced, and the noise of the motor can be reduced.

(B) The contact member according to claim 5, wherein the vibration suppressing portions (5, 22a, 32b, 6, 22).
b, 32c) are the brushes (4, 11, 21, 31)
(5, 22a, 32b) having elasticity and damping characteristics;
32b) and a weight portion (6, 22b, 32c) connected to the weight portion.

In this way, the displacement force of the brush tends to displace the weight portion via the joint, but due to the elasticity and damping characteristics of the joint, it is not transmitted instantaneously but slightly delayed. Transmitted. Therefore, the vibration when the brush is in sliding contact interferes with the displacement of the weight portion and is substantially canceled. As a result, vibration when the brush is in sliding contact can be reduced.

(C) The contact member according to (b), wherein the connecting portion (5) is formed by a rubber tube (5). With this configuration, since the connecting portion is formed of the rubber tube, the connecting portion having elasticity and damping characteristics can be configured at low cost.

[0036]

According to the present invention, in a brush sliding contact device for sliding a contact member provided with a brush to a commutator,
It is possible to provide a brush sliding contact device and a contact member that can reduce the vibration at the time of the sliding contact and can further prevent the generation of noise.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part showing a brush sliding contact device according to an embodiment.

FIG. 2 is an exploded perspective view illustrating a power supply body according to the embodiment.

FIG. 3 is an explanatory diagram schematically showing a power feeding body of the present embodiment.

FIG. 4 is a cross-sectional view of a main part showing another example of a brush sliding contact device.

FIG. 5 is a sectional view of a main part showing another example of a brush sliding contact device.

FIG. 6 is a sectional view of a main part showing another example of a brush sliding contact device.

FIG. 7 is a sectional view of a main part showing a brush sliding contact device of another example.

FIG. 8 is a cross-sectional view of a main part showing another example of a brush sliding contact device.

FIG. 9 is a cross-sectional view of a main part showing another example of a brush sliding contact device.

FIG. 10 is a sectional view of a main part showing another example of a brush sliding contact device.

FIG. 11 is a sectional view of a main part showing a conventional brush sliding device.

[Description of Signs] 1 ... Rotary axis, 2 ... Commutator, 3,10,20,30
... Feeder, 4, 11, 21, 31. Brush, 5. Combined body, 6... Weight body, 7... Brush holder, 8. Coil spring, 7b .. Wall surface, 22a, 32b.
2c ... weight part.

Claims (5)

[Claims] A commutator (2) rotating integrally with a rotating shaft (1) of a motor, and a contact member (3, 1) slidably contacting the commutator (2).
0, 20, 30) and the contact members (3, 10, 20,
30) is held in the direction of rotation of the commutator (2) in order to hold the wall (7) in the direction of rotation of the commutator (2).
b) and a biasing means (8) for biasing the contact members (3, 10, 20, 30) toward the commutator (2). The contact members (3, 10, 20, 30) are provided with brushes (4, 11,
21, 31) and the brush (4, 11, 21, 3, 3) on the rotating body (2).
The brush (4,11,2) generated when the brush (1) comes into sliding contact
The vibration suppressing unit (5, 2) for canceling the vibration of (1, 31)
2a, 32b, 6, 22b, 32c). 2. The brush sliding contact device according to claim 1, wherein the vibration suppressing portions (5, 22a, 32b, 6, 22b, 3).
2c) is connected to the brush (4, 11, 21, 31), and has a coupling portion (5, 22a, 32) having elasticity and damping characteristics.
b), and a weight portion (6, 22b, 32c) connected to the coupling portion (5, 22a, 32b). 3. The brush sliding contact device according to claim 1, wherein said urging means (8) comprises said brush (4, 11, 21, 21).
31) is a coil spring (8) that urges the vibration suppressor (5) from the side opposite to the commutator (2), and the vibration suppressing portions (5, 22a, 32b, 6, 22b, 3).
2c) A brush sliding contact device which is arranged inside the coil spring. 4. The brush sliding contact device according to claim 2, wherein the connecting portion (5) is formed of a rubber tube (5). 5. A holder (7) having a wall surface (7b) in the direction of rotation of the commutator (2) is held in the direction of rotation of the commutator (2), and the commutator (2) is biased by a biasing means (8). ) Side, and a brush (4, 4) that is in direct contact with the commutator (2) at a contact member that slides on the rotating body (2).
11, 21) and the brush (4, 11, 21) on the commutator (2).
The brush (4,1) generated when (1,31) comes into sliding contact
A contact member comprising: a vibration suppressing portion (5, 22a, 32b, 6, 22b, 32c) for canceling the vibration of (1, 21, 31).