JP2000308305A - Motor and washer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor which can prevent backlash of a rotating shaft in the axial direction, while the number of components is reduced. SOLUTION: A washer 15, interposed between a rotor 10 (core 12) and an inner ring 5b of a bearing 5, is installed with a circular ring part 15a in which a rotating shaft 11 is inserted, a protrusion 15b which is formed in the circular ring part 15a and abuts against the inner ring 5b, and a spring segment 15c which is arranged on the outer periphery of the circular ring part 15a and energizes the rotor 10 (core 12) in the axial direction. The rotating shaft 11 is energized in the axial direction by the energizing force of the spring segment 15c.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor in which a rotating shaft rotatably supported by a ball bearing is restrained from rattling in an axial direction, and a washer used for the motor.

[0002]

2. Description of the Related Art Conventionally, in a motor in which a rotating shaft is rotatably supported by a ball bearing, there is a technique for suppressing rattling of the rotating shaft in an axial direction. As an example of such a technique, there is one disclosed in Japanese Patent Application Laid-Open No. Hei 5-30701.

[0003] In the above publication, the shaft press-fitted into the rotor is loosely fitted to the inner rings of bearing bearings provided on the load side and the non-load side so as to be slidable in the axial direction, respectively. A coil spring is wound around the shaft on the non-load side, and the coil spring is interposed between the rotor and the inner ring of the bearing on the non-load side. The rotor (shaft) is constantly biased toward the load by the biasing force of the coil spring with the inner ring of the bearing as a fulcrum. In this way,
Shaking in the axial direction of the shaft is suppressed.

However, the motor disclosed in the above-mentioned publication has a problem that the size of the motor is increased in the axial direction because the coil spring is disposed along the axial direction. Therefore, such a motor is not suitable for applications in which the mounting space cannot be made large in the axial direction.

Therefore, it is conceivable to use a wave washer instead of the coil spring to prevent the motor from increasing in size in the axial direction.

[0006]

The wave washer is larger in the radial direction than the coil spring.
The washer may interfere with the outer ring. for that reason,
Normally, a flat washer is interposed between the wave washer and the inner ring of the bearing so that the wave washer does not contact the outer ring.

However, since two parts, a wave washer and a flat washer, are required, there is a problem that the number of parts increases. The present invention has been made to solve the above problems, and an object of the present invention is to provide a motor and a washer capable of suppressing rattling of a rotating shaft in an axial direction while reducing the number of parts. Is to do.

[0008]

According to a first aspect of the present invention, there is provided a motor having a rotating shaft fixed to a rotor and rotatably supported by a ball bearing. A washer is interposed between the inner ring of the bearing and the washer, and the washer is provided with an annular portion through which the rotating shaft is inserted, a protrusion provided on the annular portion, and abutting on the inner ring; A spring piece provided on the outer periphery of the ring portion and for urging the rotor in the axial direction.

According to a second aspect of the present invention, in the motor according to the first aspect, the protrusion is constituted by a plurality of protrusions or annular protrusions. According to a third aspect of the present invention, in the motor according to the second aspect, the plurality of protrusions are arranged at equal intervals in a circumferential direction.

According to a fourth aspect of the present invention, in the motor according to any one of the first to third aspects, the spring piece includes:
It is composed of a plurality of spring pieces arranged at equal intervals in the circumferential direction. According to a fifth aspect of the present invention, in the motor according to any one of the first to fourth aspects, the spring piece extends in a circumferential direction.

According to a sixth aspect of the present invention, in the motor according to the fifth aspect, the spring piece is formed so as to be narrower toward the tip, and so that the diameter of the washer is reduced.

According to a seventh aspect of the present invention, in the motor according to any one of the first to sixth aspects, the one end of the rotating shaft is an output section for driving a load, and the washer is provided with a counter output. The bearing is interposed between the inner ring of the bearing and the rotor.

The invention according to claim 8 is characterized in that the annular portion, a projection provided on the annular portion and protruding in one direction in the axial direction, and an outer periphery of the annular portion, wherein the projection is provided toward the tip. And a spring piece protruding in a direction opposite to a direction in which the portion protrudes.

According to a ninth aspect of the present invention, in the washer according to the eighth aspect, the protrusion is constituted by a plurality of protrusions or annular protrusions arranged at equal intervals in a circumferential direction. The spring piece is composed of a plurality of spring pieces arranged at equal intervals in the circumferential direction.

Therefore, according to the first aspect of the present invention,
The washer interposed between the rotor and the inner ring of the bearing is provided on an annular portion through which the rotating shaft is inserted, a protrusion provided on the annular portion, and a projection abutting on the inner ring, and provided on the outer periphery of the annular portion. ,
A spring piece for urging the rotor in the axial direction. Therefore, the rattling of the rotor and the rotating shaft in the axial direction is suppressed by the urging force of the spring piece. In addition, since only one washer is used, the number of parts is reduced.

According to the second aspect of the present invention, since the projection is constituted by a plurality of projections or annular projections, the washer always comes into contact with the inner ring of the bearing in a stable state. According to the third aspect of the present invention, since the plurality of projections are arranged at equal intervals in the circumferential direction, the washer always comes into contact with the inner ring of the bearing in a stable state.

According to the fourth aspect of the present invention, since the spring piece is constituted by a plurality of spring pieces arranged at equal intervals in the circumferential direction, a stable urging force is applied to the rotor.
According to the invention described in claim 5, since the spring piece extends in the circumferential direction, the diameter of the washer can be small.

According to the sixth aspect of the present invention, the spring piece is formed so as to become narrower toward the distal end, so that the diameter of the washer becomes smaller. Therefore, the space occupied by the washer can be small.

According to the seventh aspect of the present invention, since the washer is interposed between the inner ring of the bearing on the opposite side to the output portion and the rotor, the rotating shaft is attached to the output portion by the urging force of the washer. Be inspired.

According to the eighth aspect of the present invention, the washer is provided on the annular portion, the projecting portion provided on the annular portion and protruding in one axial direction, and the washer is provided on the outer periphery of the annular portion toward the tip. And a spring piece protruding in a direction opposite to the protruding direction of the protruding portion. Then, such a washer is inserted between the rotor and the inner ring of the bearing by inserting the annular portion through the rotating shaft. At this time, the protrusion contacts the inner race, and the spring piece urges the rotor in the axial direction.

According to the ninth aspect of the present invention, the protrusion is constituted by a plurality of protrusions or annular protrusions arranged at regular intervals in the circumferential direction, and the spring pieces are arranged at regular intervals in the circumferential direction. It is composed of a plurality of arranged spring pieces. Therefore, when such a washer is interposed between the rotor and the inner ring of the bearing, the washer always comes into contact with the inner ring of the bearing in a stable state, and applies a stable urging force to the rotor.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 1, a housing 2 of the DC motor 1 includes a bottomed cylindrical yoke 3 and an end frame 4 that closes an opening of the yoke 3.

A cylindrical bearing holding portion 3a is formed at the center of the bottom of the yoke 3, and the outer ring 5a of the ball bearing 5 is press-fitted and held in the holding portion 3a. A plurality of magnets 6 are fixed to the inner peripheral surface of the yoke 3. A cylindrical bearing holding portion 4a is formed at the center of the end frame 4, and the outer ring 7a of the ball bearing 7 is provided on the holding portion 4a.
Is fixed. A brush holder 9 for holding a brush 8 is attached to the end frame 4. And yoke 3
And the rotor 1 in the space formed by the
0 is rotatably supported.

The rotor 10 has a rotating shaft 11 and the rotating shaft 1
1 is fixed to the core 12. A winding 13 is wound around the core 12, and the winding 13 is electrically connected to a commutator 14. The commutator 14 is fixed to the rotating shaft 11, and the brush 8 slides on the commutator 14. The rotating shaft 11 is pressed into the inner ring 7 b of the bearing 7 and is loosely fitted to the inner ring 5 b of the bearing 5. The rotation shaft 11 has a portion protruding from the end frame 4 as an output portion, and the output portion drives a load.

As shown in FIG. 1 and FIG.
A washer 15 inserted between the rotating shaft 11 is interposed between the core 12 and the inner ring 5b of the bearing 5. The washer 15 has an annular portion 15a through which the rotating shaft 11 is inserted as shown in FIG. On one surface of the annular portion 15a, three projections 15b arranged at equal intervals in the circumferential direction are formed, and come into contact with the end surface of the inner ring 5b of the bearing 5.

On the outer periphery of the annular portion 15a, three spring pieces 15c arranged at equal intervals in the circumferential direction are integrally formed.
Each spring piece 15c has a proximal end 15d extending radially outward and a distal end 15e extending from the proximal end 15d in the counterclockwise direction in FIG. 3 in the circumferential direction to the vicinity of the adjacent spring piece 15c. The spring piece 15c is formed such that the tip 15e protrudes in the direction opposite to the direction in which the protrusion 15b protrudes. Accordingly, the spring piece 15c is
Abuts against the end face of the core 12 and
Press in the direction opposite to the direction of protrusion. Further, the distal end portion 15e is formed such that the width thereof becomes narrower toward the distal end, and the diameter of the washer 15 becomes smaller.

The washer 15 having such a configuration is provided with the core 1
2 and the inner ring 5b of the bearing 5 is attached by being compressed in the axial direction. The rotor 10 (rotary shaft 11) is always urged in the direction of arrow A in FIG. 1 by the urging force of the washer 15 (spring piece 15c) with the inner ring 5b as a fulcrum. In this way, the rattling of the rotating shaft 11 in the axial direction is suppressed.

Further, since the washer 15 abuts on the inner race 5b by the projection 15b, even if the spring piece 15c bends to the annular portion 15a due to the force acting on the rotating shaft 11 in the direction opposite to the arrow A direction, the spring piece 15c Does not contact the outer ring 5 a of the bearing 5.

As described above, in the present embodiment, the following functions and effects can be obtained. (1) The washer 15 of the present embodiment is provided with a spring piece 15c that abuts on the core 12 and has an elastic force, and a projection 15b that abuts on the inner ring 5b of the bearing 5. Attached with axial compression between them. Therefore, the rotor 10 (rotary shaft 11) is always urged in the direction of arrow A in FIG. 1 by the urging force of the washer 15 (spring piece 15c), so that rattling of the rotary shaft 11 in the axial direction is suppressed. Can be. Also, washer 15
Abuts on the inner ring 5b by the projection 15b,
Even if 5c is bent to the annular portion 15a, the spring piece 15c does not contact the outer ring 5a of the bearing 5. Moreover, in this embodiment, since only one washer 15 is used, the number of parts can be reduced as compared with the conventional case.

(2) Due to the urging force of the washer 15, the inner rings 5b and 7b of the bearings 5 and 7 are each applied with a pressure outward in the axial direction. For this reason, occurrence of rattling in both bearings 5 and 7 can be suppressed. Therefore, the life of both bearings 5 and 7 can be improved.

(3) The inner ring 5b of the bearing 5 and the rotating shaft 11 rotate integrally by the urging force of the washer 15. Therefore, the inner ring 5b and the rotating shaft 11 do not come into sliding contact with each other, so that the generation of the sliding contact noise can be suppressed and the wear of the rotating shaft 11 and the inner ring 5b due to the sliding contact can be suppressed. Further, since the washer 15 does not make sliding contact with the core 12 and the inner ring 5b, the generation of the sliding contact noise can be suppressed, and the wear of the washer 15, the core 12, and the inner ring 5b due to the sliding contact can be suppressed. .

(4) Since a plurality of projections 15b abutting on the inner ring 5b are arranged at equal intervals in the circumferential direction, the projections 15b can always abut on the inner ring 5b in a stable state. (5) Since a plurality of spring pieces 15c abutting on the core 12 are arranged at equal intervals in the circumferential direction, a stable urging force can be constantly applied to the core 12. In addition, by this urging force, a stable pressurization can always be applied to the inner rings 5b and 7b of the bearings 5 and 7.

(6) Since the tip 15e of the spring piece 15c extends along the circumferential direction, the diameter of the washer 15 can be reduced. Therefore, the winding 1 of the core 12
The reduction of three spaces can be suppressed, and the increase in the size of the rotor 10 in the radial direction can be suppressed.

(7) The distal end 15e of the spring piece 15c is formed so that its width becomes narrower toward its distal end, and the diameter of the washer 15 becomes smaller. That is, the space occupied by the washer 15 is reduced. Therefore, it is possible to suppress a decrease in the space of the winding 13 of the core 12 and to suppress an increase in the size of the rotor 10 in the radial direction.

The embodiment of the present invention may be modified as follows. In the above embodiment, as shown in FIG.
Was formed, but is not limited to this shape. For example, the number, arrangement, and shape of the projections 15b and the spring pieces 15c are not limited thereto. Further, a plurality of bent pieces may be formed instead of the protrusion 15b. Further, an annular ridge 15f may be formed as shown in FIG.

In the above embodiment, the washer 15 is interposed between the inner ring 5b of the bearing 5 on the side opposite to the output portion and the core 12 to urge the rotating shaft 11 in the direction of arrow A. , The brush holder 9 is arranged on the side opposite to the output section,
The rotating shaft 11 is loosely fitted and supported on the inner ring 7 b of the bearing 7 on the output side, and a washer 1 is provided between the inner ring 7 b and the core 12.
The rotation shaft 11 may be urged in the direction opposite to the arrow A direction with the interposition of the rotation shaft 5. That is, it is only necessary that the rotating shaft 11 can be biased in any of the axial directions.

In the above embodiment, the present invention is applied to the DC motor 1 as shown in FIG. 1, but may be applied to a motor having another configuration. The technical ideas other than the claims that can be grasped from the above embodiments will be described below together with their effects.

(A) The washer according to claim 8 or 9, wherein the spring piece (15c) extends in a circumferential direction. In this case, since the spring piece extends in the circumferential direction, the diameter of the washer can be small.

(B) In the washer according to the above (a), the spring piece (15c) is formed so as to become narrower toward the tip, so that the diameter of the washer (15) becomes smaller. Washer characterized by the following. By doing so, the space occupied by the washer can be reduced.

[0040]

As described in detail above, according to the present invention,
It is possible to provide a motor and a washer capable of suppressing the backlash in the axial direction of the rotating shaft while reducing the number of parts.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a motor according to the present embodiment.

FIG. 2 is an enlarged sectional view of a main part of the motor.

FIG. 3 is a perspective view of a washer.

FIG. 4 is a perspective view of a washer in another example.

[Explanation of symbols]

5: ball bearing, 5b: inner ring, 10: rotor, 1
DESCRIPTION OF SYMBOLS 1 ... Rotating shaft, 15 ... Washer, 15a ... Annular part, 15b
... Projection as projection, 15c. Spring piece, 15f.

Claims (9)

[Claims] 1. A motor comprising a rotor (10) having a rotating shaft (11) rotatably supported by a ball bearing (5), wherein the rotor (10) and an inner race (5) of the bearing (5) are provided.
b), a washer (15) is interposed therebetween, and the washer (15) is provided on the annular portion (15a) through which the rotary shaft (11) is inserted, and on the annular portion (15a). A protrusion (15b, 15f) abutting on the inner ring (5b), and an outer periphery of the annular portion (15a);
A motor comprising: a spring piece (15c) for urging the spring in the axial direction. 2. The motor according to claim 1, wherein the protrusions (15b, 15f) have a plurality of protrusions (15b).
Alternatively, the motor is constituted by an annular ridge (15f). 3. The motor according to claim 2, wherein the plurality of projections (15b) are arranged at equal intervals in a circumferential direction. 4. The motor according to claim 1, wherein the spring pieces (15c) are constituted by a plurality of spring pieces arranged at equal intervals in a circumferential direction. And the motor. 5. The motor according to claim 1, wherein the spring piece (15c) extends in a circumferential direction. 6. The motor according to claim 5, wherein the spring piece (15c) is formed so as to be narrower toward the tip, and is formed so that the diameter of the washer (15) becomes smaller. And the motor. 7. The motor according to claim 1, wherein one end of the rotating shaft is an output unit for driving a load, and the washer is an anti-output unit. A motor interposed between the inner ring (5b) of the bearing (5) on the side and the rotor (10). 8. An annular portion (15a), a projection (15b, 15f) provided on the annular portion (15a) and protruding in one direction in the axial direction, and provided on an outer periphery of the annular portion (15a). , The protrusion (15
Spring piece (15c) projecting in the direction opposite to the projecting direction of b)
A washer comprising: 9. The washer according to claim 8, wherein the protrusions (15b, 15f) are a plurality of protrusions (15b) arranged at equal intervals in a circumferential direction or an annular protrusion (15).
f) wherein the spring pieces (15c) are constituted by a plurality of spring pieces arranged at equal intervals in a circumferential direction.