JP3645501B2 - Brush device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a brush device for bringing a brush into contact with a commutator of a motor.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a commutator (commutator) is provided on a rotating shaft of a DC motor, and a brush for power supply is in contact with the commutator. And as a brush apparatus which makes a brush contact a commutator, there exists a thing as shown in FIG. The brush device includes a brush holder 53 having an inner side surface 53a extending in a substantially radial direction of a commutator 52 fixed to a rotating shaft 51, a brush 54 accommodated and held in the brush holder 53, and a tip of the brush 54 And a torsion coil spring 55 for pressing the portion against the commutator 52. An inner side surface 53 a of the brush holder 53 is inclined toward one end side (downward in FIG. 5) in the axial direction of the commutator 52 with respect to the direction orthogonal to the axis of the commutator 52. The inner surface 53a of the brush holder 53 is set so as to accommodate and hold the brush 54 with a gap in consideration of thermal expansion of the brush 54 and the like. The torsion coil spring 55 is supported by the support column 56 so that the axial direction of the coil portion 55a is substantially parallel to the axial direction of the commutator 52 (rotating shaft 51), and the brush 54 is supported in the direction of the commutator 52 (substantially orthogonal to the axis). The commutator 52 is pressed and contacted by the urging force F11 in the direction).
[0003]
In the brush device configured as described above, when a driving current is supplied from a power supply device (not shown) to the brush 54 via the pigtail 54a, the brush device 54 is wound around an armature core (not shown) via the commutator 52. A drive current is supplied to the winding, and the rotary shaft 51 is driven to rotate. When the commutator 52 (rotating shaft 51) rotates, the brush 54 is slidably contacted with the commutator 52, and a drive current is always supplied from the brush 54 to the commutator 52. At this time, since the brush 54 is slidably contacted with the rotating commutator 52, the brush 54 receives an irregular (slightly changing) reaction force R11 from the commutator 52, but the inner surface 53a of the brush holder 53 is Since it is inclined with respect to the direction perpendicular to the axis of the commutator 52, the reaction force R11 from the commutator 52 is received by the inner side surface 53a of the brush holder 53 (the frictional force of the inner side surface 53a), and its vibration is suppressed. . Therefore, the generation of noise based on the vibration of the brush 54 is suppressed.
[0004]
[Problems to be solved by the invention]
However, in the brush device as described above, there is a gap between the brush holder 53 and the brush 54, and the torsion coil spring 55 urges the brush 54 in the direction of the commutator 52 (substantially perpendicular to the axis) with the urging force F11. Therefore, the brush 54 is inclined with respect to the inner side surface 53 a of the brush holder 53. Then, a part of the inner side surface 53a receives the reaction force R11 locally to generate reaction forces R12 and R13 on a part of the inner surface 53a, and the brush 54 becomes hot. There is a possibility that a part of 53 is deformed. This causes damage to the normal posture and function of the brush 54.
[0005]
The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a brush device capable of preventing deformation of the brush holder while suppressing vibration of the brush.
[0006]
[Means for Solving the Problems]
The invention described in claim 1 includes a brush holder having an inner surface that extends in a substantially radial direction of the commutator and is inclined toward one end side in the axial direction of the commutator toward the commutator, and a gap in the brush holder. A torsion coil spring in which the axis orthogonal direction line of the coil portion is inclined at an angle larger than the inclination angle of the inner side surface in a brush device comprising a brush which is housed and held in a state and whose tip is pressed against the commutator One end of the torsion coil spring is engaged with an engagement groove formed at a position above the central axis in the longitudinal direction of the brush, and the rear end of the brush is connected to the inner surface by the torsion coil spring. by biasing the inclination angle than in a direction inclined to an angle larger, with to press contact the tip of the brush to the commutator, the rear end side of the brush Before biasing the Kijikusen direction one end side.
[0009]
According to a second aspect of the invention, the brush device of claim 1, the struts for supporting the inserted through the coil portion of the torsion coil spring said coil portion, so as to extend in the axial direction of the commutator And it formed so that it might be loosely fitted in this coil part.
[0010]
According to a third aspect of the invention, the brush device according to claim 1 or 2, the rear end portion of the brush, the other end of the torsion coil spring to form a engaging groove for engaging.
[0011]
(Function)
According to the first aspect of the present invention, since the brush holder has an inner surface inclined toward one end in the axial direction of the commutator, the brush holder is housed and held in the brush holder, and its tip is pressed against the commutator. The vibration of is suppressed. In addition, since the rear end side of the brush is urged toward one end in the axial direction of the commutator, the brush comes into surface contact with the surface on the one end side in the axial direction on the inner surface of the brush holder. Therefore, it is prevented that a force is locally applied to a part of the brush holder. As a result, deformation of the brush holder is prevented.
[0012]
In addition , since the means for pressing the tip of the brush against the commutator and the means for urging the brush rear end toward the one end in the axial direction of the commutator are configured by one torsion coil spring , the number of parts is reduced. Does not increase.
[0013]
The urging means is a torsion coil spring that is urged by a torsional force, and the axis-perpendicular direction line of the coil portion is provided to be inclined at an angle larger than the inclination angle of the inner side surface. Therefore, the rear end portion of the brush is biased by the torsion coil spring in a direction inclined to an angle larger than the inclination angle of the inner surface.
[0014]
According to the second aspect of the present invention, the support for inserting the coil portion of the torsion coil spring and supporting the coil portion is loosely fitted to the coil portion so as to extend in the axial direction of the commutator. Therefore, the support column can be easily formed integrally with a brush holder member or the like as a base using a mold or the like, and the axis orthogonal direction line of the coil portion can be inclined.
[0015]
According to the invention of claim 3, the rear end portion of the brush engaging groove for the other end of the torsion coil spring is engaged is formed. Thus, the other end of the torsion coil spring can be reliably connected to the brush in a simple shape.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment in which the present invention is embodied in a motor will be described with reference to FIGS.
[0017]
As shown in FIG. 1, the motor 1 includes a motor body 2 and a speed reduction unit 3. The yoke 4 of the motor body 2 is formed in a bottomed cylindrical shape, and a rotating shaft 5 is rotatably supported by the yoke 4 by bearings 6a and 6b. An armature core 8 around which a winding 7 is wound and a commutator (commutator) 9 are fixed to the rotating shaft 5. A plurality of magnets M are fixed to the inner peripheral surface of the yoke 4 facing the armature core 8.
[0018]
A worm shaft 11 is rotatably supported by bearings 12a and 12b in the gear housing 10 of the speed reduction unit 3. The gear housing 10 rotatably supports a worm wheel 13 that meshes with the worm 11a of the worm shaft 11, and the worm wheel 13 is connected to an output shaft (not shown). The speed reduction unit 3 is fixed to the motor main body 2 with the gear housing 10 screwed to the flange 4a extending from the opening of the yoke 4 and the worm shaft 11 connected to the rotary shaft 5. ing.
[0019]
A brush holder member 14 made of an insulating resin material is fixed between the opening of the yoke 4 and the opening of the gear housing 10. As shown in FIGS. 2 and 3, a pair of brush devices 15 (only one is shown in FIG. 3) is provided on the inner side end surface 14 a of the yoke 4 of the brush holder member 14. The brush device 15 includes a brush holder 16, a brush 17, a support column 18, a support protrusion 19, and a torsion coil spring 20 as an urging means.
[0020]
As shown in FIGS. 2 and 3, the brush holder 16 is composed of a pair of wall portions 14 b and a lid portion 14 c erected on the inner side end surface 14 a of the brush holder member 14, and in the substantially radial direction of the commutator 9. The inner side surface 16a extends in the longitudinal direction of the inner side end surface 14a and is inclined toward one end side in the axial direction of the commutator 9 (lower side in FIGS. 1 and 3) toward the commutator 9. Note that the inner side surface 16 a of the present embodiment is inclined by about 10 degrees with respect to the direction perpendicular to the axis of the commutator 9. The inner surface 16a of the brush holder 16 is set to accommodate and hold the brush 17 with a gap in consideration of thermal expansion of the brush 17 and the like. A wall slit 14d (see FIG. 3) extending in the radial direction of the commutator 9 is formed in the wall 14b of the brush holder 16, and a lid slit 14e (in FIG. 3) extending in the radial direction of the commutator 9 is formed in the lid 14c. 2) is formed.
[0021]
The brush 17 is housed and held in the brush holder 16. An engagement groove 17 a is formed in the rear end portion of the brush 17 so as to be recessed in the tip direction of the brush 17. In addition, one end of a pigtail 21 is embedded in the upper part of the rear end side of the brush 17. The pigtail 21 protrudes from the lid slit 14e to the outside of the brush holder 16, and is connected to an external power supply device (not shown) via the choke coil 22 and the like.
[0022]
The support column 18 is erected on the inner side end surface 14 a of the brush holder member 14 at a position shifted from the radially outer portion of the brush holder 16 in the short direction of the inner side end surface 14 a. The support column 18 of the present embodiment is formed in a cylindrical shape. Moreover, the support | pillar 18 is formed so that it may extend in the axial direction (parallel) of the commutator 9 (rotating shaft 5).
[0023]
The support protrusion 19 is erected on the inner side end surface 14 a of the brush holder member 14 at a position shifted from the radially outer side of the brush holder 16 to the outer side in the longitudinal direction of the inner side end surface 14 a. As shown in FIG. 3, a locking groove 19a is formed in the upper portion of the end surface of the support protrusion 19 on the brush 17 side. Note that the locking groove 19a of the present embodiment is formed at a position above the central axis L1 in the longitudinal direction of the brush 17.
[0024]
The torsion coil spring 20 includes a coil portion 20a, one end protruding portion 20b protruding from one end of the coil portion 20a, and the other end protruding portion 20c protruding from the other end of the coil portion 20a. The torsion coil spring 20 of the present embodiment is formed so that the tip ends of the one end protruding portion 20b and the other end protruding portion 20c are arranged on the same axis orthogonal direction at the axial center position of the coil portion 20a. Yes. In addition, here, the outer diameter of the support column 18 is set smaller than the inner diameter of the coil portion 20a.
[0025]
The torsion coil spring 20 is configured so that the support column 18 is loosely fitted to the coil portion 20a, and the tip end portion of the one end protruding portion 20b is locked to the locking groove 19a of the support protruding portion 19. And the front-end | tip part of the other end protrusion part 20c is arrange | positioned so that the engagement groove | channel 17a of the brush 17 may be engaged. The other end protruding portion 20c penetrates through the wall slit 14d of the wall 14b of the brush holder 16 and is engaged with the engaging groove 17a. At this time, the torsion coil spring 20 is disposed such that the axis orthogonal direction line L2 of the coil portion 20a is inclined at an angle larger than the inclination angle of the inner surface 16a of the brush holder 16. In addition, the inclination described here is an inclination with respect to the direction perpendicular to the axis of the commutator 9, and is an inclination of an angle smaller than 90 degrees. The torsion coil spring 20 urges the rear end portion (engagement groove 17a) of the brush 17 to the commutator 9 side in the direction perpendicular to the axis L2 by the urging force F1. Here, since the axis orthogonal direction line L2 is inclined at an angle larger than the inner surface 16a of the brush holder 16, the tip of the brush 17 is pressed against the commutator 9 by the torsion coil spring 20. The rear end of the brush 17 is urged toward one end in the axial direction of the commutator 9 (the lower side in FIGS. 1 and 3).
[0026]
In the motor 1 (brush device 15) configured as described above, when a driving current is supplied from a power supply device (not shown) to the brush 17 via the pigtail 21 or the like, the armature core 8 is supplied from the brush 17 via the commutator 9. A driving current is supplied to the winding 7 wound around the rotary shaft 5, and the rotary shaft 5 is driven to rotate. Then, the worm shaft 11 rotates according to the rotation of the rotating shaft 5, and the worm wheel 13 (output shaft) rotates according to the rotation. When the commutator 9 (rotary shaft 5) rotates, the brush 17 is slidably contacted with the commutator 9, and a drive current is always supplied from the brush 17 to the commutator 9, so that the rotational drive of the rotary shaft 5 is maintained.
[0027]
Next, characteristic effects of the above embodiment will be described below.
(1) Since the brush 17 is slidably contacted with the rotating commutator 9 during driving, the brush 17 receives an irregular (a slight change with time) reaction force R1 from the commutator 9. Since the side surface 16a is inclined with respect to the direction perpendicular to the axis of the commutator 9, the reaction force R1 from the commutator 9 is received by the inner side surface 16a of the brush holder 16 (friction force of the inner side surface 16a), and its vibration is It is suppressed. Therefore, the generation of noise based on the vibration of the brush 17 is suppressed. Moreover, since the rear end portion (engagement groove 17 a) of the brush 17 is biased toward one end side in the axial direction of the commutator 9 (lower side in FIGS. 1 and 3), the brush 17 The side surface 16a is in surface contact with the surface on the one end side in the axial direction (the bottom surface in FIGS. 1 and 3). Therefore, the reaction force R1 is received in the range S having the same area as the surface of the inner surface 16a, specifically, the lower surface of the brush 17, and the reaction force R2 is generated in the entire range S of the inner surface 16a. Therefore, it is prevented that a force is locally applied to a part of the brush holder 16. Thereby, the deformation of the brush holder 16 is prevented. As a result, the normal posture and function of the brush 17 are maintained.
[0028]
(2) The torsion coil spring 20 is arranged such that the axis orthogonal direction line L2 of the coil portion 20a is inclined at an angle larger than the inclination angle of the inner surface 16a of the brush holder 16. Therefore, the rear end portion (engagement groove 17a) of the brush 17 is urged by the torsion coil spring 20 in a direction inclined at an angle larger than the inclination angle of the inner surface 16a. If it does in this way, the means which presses and contacts the front-end | tip part of the brush 17 to the commutator 9, and the means which urges the rear end side of the brush 17 to the axial direction one end side (lower side in FIG.1 and FIG.3) of the commutator 9 Are constituted by the torsion coil spring 20 which is one urging means, so that the number of parts of the brush device 15 does not increase.
[0029]
(3) The support column 18 for inserting the coil portion 20a of the torsion coil spring 20 to support the coil portion 20a extends in the axial direction of the commutator 9 (in parallel) and has an outer diameter of the coil portion 20a. Smaller than the inner diameter of the coil portion (so as to be loosely fitted to the coil portion 20a). Therefore, the support column 18 can be easily formed integrally with the brush holder member 14 using, for example, a mold or the like, and the axis orthogonal direction line L2 of the coil portion 20a can be inclined.
[0030]
(4) At the rear end portion of the brush 17, an engagement groove 17 a with which the other end protruding portion 20 c of the torsion coil spring 20 is engaged is formed. If it does in this way, the other end protrusion part 20c of the torsion coil spring 20 can be reliably connected with the brush 17 with a simple shape.
[0031]
The above embodiment may be modified as follows.
In the above embodiment, the column 18 is formed in a cylindrical shape so as to extend (parallel) in the axial direction of the commutator 9 and the outer diameter is smaller than the inner diameter of the coil portion 20a. If it can support in the state which inclined part 20a, you may change into other shapes. For example, you may change to the support | pillar 31 shown in FIG. The support column 31 is formed to extend (in parallel) in the axial direction of the commutator 9. The support 31 is formed with an inclined portion 31a along the same inclination angle so as to maintain the inclination angle of the coil portion 20a. The inclined portion 31a is formed on a part of the column 31 (on the support projection 19 side, on the right side in FIG. 4) so that the cross-sectional area of the column 31 decreases toward the tip of the column 31. ing. If it does in this way, the coil part 20a of the torsion coil spring 20 will be hold | maintained in the inclination part 31a formed in the support | pillar 31 at the angle larger than the inclination angle of the said inner surface 16a. In addition, the inclined portion 31a is formed on a part of the support 31 so that the cross-sectional area of the support 31 is reduced toward the tip of the support 31, so that the support 31 is formed using a mold or the like. When forming integrally with the brush holder member 14 or the like, the mold that is moved and pulled out in the direction of the tip of the column 31 is easily removed, and the moldability is improved.
[0032]
In the above embodiment, the torsion coil spring 20 presses the tip of the brush 17 against the commutator 9, and the rear end of the brush 17 is at one end in the axial direction of the commutator 9 (in FIGS. 1 and 3). The lower end of the brush 17 is pressed against the commutator 9 and the rear end of the brush 17 is moved to one end in the axial direction of the commutator 9 (lower side in FIGS. 1 and 3). The biasing means may be composed of different members. Even in this case, vibration of the brush is suppressed and deformation of the brush holder is prevented.
[0033]
In the above embodiment, the rear end of the brush 17 is arranged by inclining the axis orthogonal direction line L2 of the coil portion 20a of the torsion coil spring 20 at an angle larger than the inclination angle of the inner surface 16a of the brush holder 16. The portion (engagement groove 17a) was urged in a direction inclined to an angle larger than the inclination angle of the inner side surface 16a, but the rear end portion (engagement groove 17a) of the brush 17 was set to an angle larger than the inclination angle of the inner side surface 16a. As long as it can urge in the inclined direction, it may be changed to another urging means. For example, the rear end portion (engagement groove 17a) of the brush 17 may be biased in a direction inclined to an angle larger than the inclination angle of the inner surface 16a by the force of the compression coil spring. In this case, the support column 18 is not necessary, and the shape and the like of the support protrusion 19 must be changed as appropriate. Even in this case, vibration of the brush is suppressed and deformation of the brush holder is prevented. Moreover, the number of parts of the brush device does not increase.
[0034]
In the above embodiment, the engagement groove 17a is formed in the rear end portion of the brush 17, and the other end protruding portion 20c of the torsion coil spring 20 is engaged and connected. You may connect a torsion coil spring to a part. Even if it does in this way, the effect similar to the effect (1)-(3) of the said embodiment can be acquired.
[0035]
In the above embodiment, the brush device 15 is embodied in a motor having a pair (two), but the brush device 15 is embodied in a motor (for example, a wiper motor) having another number (for example, three). Also good. Even if it does in this way, the effect similar to the effect of the said embodiment can be acquired.
[0036]
In the above embodiment, the motor 1 including the speed reduction unit 3 is embodied. However, the motor 1 may be embodied to another motor that does not include the speed reduction unit 3. Even if it does in this way, the effect similar to the effect of the said embodiment can be acquired.
[0037]
The technical idea that can be grasped from the above embodiment will be described below together with the effects thereof.
Wherein inserting the coil portion (20a) the coil part of the (b) pre-Symbol torsion coil spring (20) and (20a) strut (31) for supporting a, so as to extend in the axial direction of the commutator (9) The brush device is characterized in that an inclined portion (31a) along the inclination angle is formed on the support column (31) so as to maintain the inclination angle of the coil portion (20a). If it does in this way, the coil part of a torsion coil spring is hold | maintained in the inclination part formed in a support | pillar at the angle whose axis orthogonal direction line is larger than the inclination angle of the said inner surface.
[0038]
(B) pre-Symbol inclined portion (31a) so as to reduce the cross-sectional area of the struts increases toward the distal end of the strut (31), and being formed in a portion of the struts (31) Brush device to do. In this case, the inclined portion is formed in a part of the support so that the cross-sectional area of the support becomes smaller toward the tip of the support. Therefore, the support is used, for example, by using a mold or the like. When integrally forming on a brush holder member or the like serving as a table, the mold that is moved and pulled out in the direction of the tip of the column is easily removed, and the moldability is improved.
[0039]
(C) motor with the brush device (15). If it does in this way, the motor which can prevent a deformation | transformation of a brush holder can be provided, suppressing the vibration of a brush.
[0040]
【The invention's effect】
As described above in detail, according to the present invention, it is possible to provide a brush device capable of preventing the deformation of the brush holder while suppressing the vibration of the brush.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a main part of a motor in the present embodiment.
FIG. 2 is a cross-sectional view taken along line AA in FIG.
FIG. 3 is a schematic diagram of a brush device according to the present embodiment.
FIG. 4 is a schematic diagram of a brush device according to another example.
FIG. 5 is a schematic diagram of a brush device according to the prior art.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 9 ... Commutator, 16 ... Brush holder, 17 ... Brush, 18 ... Strut, 20 ... Torsion coil spring (biasing means), 16a ... Inner side surface, 17a ... Engagement groove, 20a ... Coil part, 20c ... Other end protrusion part , L2: Axis orthogonal direction line of the coil part.

Claims (3)

A brush holder (16) extending in a substantially radial direction of the commutator (9) and having an inner surface (16a) inclined toward one end side in the axial direction of the commutator (9) toward the commutator (9);
In the brush device comprising a brush (17) which is housed and held in a state having a gap in the brush holder (16) and whose tip is pressed against the commutator (9),
A torsion coil spring (20) is provided by inclining an axis orthogonal direction line (L2) of the coil portion (20a) at an angle larger than the inclination angle of the inner surface (16a), and one end portion of the torsion coil spring (20) ( 20b) is locked in a locking groove (19a) formed at a position above the longitudinal central axis (L1) of the brush (17), and the torsion coil spring (20) By urging the rear end portion in a direction inclined at an angle larger than the inclination angle of the inner side surface (16a), the tip end portion of the brush (17) is pressed against the commutator (9) and the brush ( brush apparatus characterized by biasing the rear end of the 17) before Kijikusen direction end side. The brush device according to claim 1, wherein
A column (18) for inserting the coil portion (20a) of the torsion coil spring (20) and supporting the coil portion (20a) extends in the axial direction of the commutator (9) and the coil portion. A brush device formed so as to be loosely fitted in (20a) . The brush device according to claim 1 or 2,
The brush device according to claim 1, wherein an engagement groove (17a) for engaging the other end portion (20c) of the torsion coil spring (20) is formed at a rear end portion of the brush (17) .

Images