JPH08298743A - Electric rotating machine - Google Patents

Abstract

PURPOSE: To provide an electric rotating machine having a structure in which the exhaustion preventive means of a wave washer can be installed with high accuracy without increasing the number of working processes. CONSTITUTION: Bearing holding recessed parts 10 are formed on both sides in the length direction of a stator support tube part 1. A radial bearing is arranged in every bearing holding recessed part 10, and a shaft is supported by the radial bearing so as to be freely rotatable. A wave washer 14 is arranged between the edge of an outer ring at the radial bearing and the inner edge 10a of every bearing holding recesses part 10. A plurality of stopper protrusions 19 are formed so as to protrude on the inner edge 10a of every bearing holding recessed part 10 in such a way that their tips are inserted into a plurality of recessed parts 14a at the wave washer 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to rotary electric machines such as electric motors and generators.

[0002]

2. Description of the Related Art FIG. 6 shows the structure of a brushless DC motor as an example of a conventional rotary electric machine of this type.

In the brushless DC motor, a stator 2 is attached to the outer circumference of a stator support cylinder portion 1, and a rotor 3 is rotatably arranged on the outer circumference of the stator 2. The stator 2 has a structure in which a stator coil 5 is wound around each pole portion of a stator core 4. The rotor 3 has a structure in which a permanent magnet 7 is attached to the inner circumference of a cup-shaped yoke 6.

A rotary shaft 9 is passed through the shaft through hole 8 of the stator support cylinder portion 1, and the rotary shaft 9 is disposed in the bearing holding recesses 10 and 11 on both sides of the stator support cylinder portion 1 in the longitudinal direction. 12 and 13 are rotatably supported. These radial bearings 12 and 13 have inner ring 12
It has a structure in which a plurality of steel balls 12c and 13c are arranged between a and 13a and outer rings 12b and 13b. The shaft through hole 8 has a small diameter hole portion 8 on the radial bearing 12 side.
The large-diameter hole portion 8b is formed on the radial bearing 13a side.

One of the radial bearings 12, 13 is provided with a wave washer 14 as a pressing spring for absorbing the play in the axial direction of the rotary shaft 9.

A rotor 3 is supported on the rotating shaft 9. That is, the rotating shaft 9 is fixed to the boss portion 6 a provided in the center of the cup-shaped yoke 6 of the rotor 3 on the bottom side, and the rotor 3 is supported by the cup-shaped yoke 6.

On the radial bearing 13 side, a printed circuit board 15 on which the control circuit of the brushless DC motor is mounted is fixed to the outer periphery of the stator support cylinder 1 by a fixing portion 16 to an insulating spacer 17 on the end face of the stator 2. .

In such a brushless DC electric motor, as shown in FIGS. 7A and 7B and FIG.
In order to stop the axial movement of the second inner ring 12a and absorb the play in the axial direction of the rotating shaft 9, the outer peripheral surface of the small diameter hole portion 8a in the inner end surface 10a of the bearing holding recess 10 of the stator support tubular portion 1 is provided. A ring-shaped stopper portion 18 is provided.

In this case, depending on the type of brushless DC motor, the stopper portion 18 may not be provided.

[0010]

However, such a conventional rotating electric machine has the following problems.

(A) In a rotary electric machine in which the stopper portion 18 is not provided on the inner end surface 10a of the bearing holding recessed portion 10, the wave washer 14 sinks due to the axial movement of the rotary shaft 9 and noise is generated due to play. There is a risk of

(B) In the rotary electric machine in which the stopper portion 18 is provided on the inner end surface 10a of the bearing holding recess 10 as shown in FIGS. 5A and 5B, the stopper portion is provided on the center side of the bearing holding recess 10. Since 18 is provided, the small diameter hole portion 8a
Since the inner diameter d1 of the bearing is reduced and the bearing holding recess 10 is cut with a cutting tool and then the cutting tool holding recess 11 on the opposite side is cut by passing the cutting tool through the small diameter hole 8a, the small diameter hole 8
If the inner diameter d1 of a is small, the bite does not pass, and the bearing holding recess 10 and the bearing holding recess 11 cannot be processed at the same time, and chuck change is required at the time of processing lowering, which easily causes misalignment, and processing The man-hour also increases.

An object of the present invention is to provide a rotating electric machine having a structure in which the sag preventing means for the wave washer can be provided with high accuracy without increasing the number of processing steps.

[0014]

According to the present invention, a stator is attached to the outer circumference of a stator support cylinder, a rotor is rotatably arranged on the outer circumference of the stator, and a rotary shaft is provided in a shaft through hole of the stator support cylinder. The rotary shaft is pierced through and is rotatably supported by radial bearings arranged in bearing holding recesses on both sides in the longitudinal direction of the stator support tubular portion, and at least one of the radial bearings has a play in the axial direction of the rotary shaft. A rotary electric machine in which a wave washer that absorbs is disposed and a rotor is supported on a rotation shaft is targeted for improvement.

In the rotating electric machine according to the present invention, the wave washer is disposed between the end surface of the outer ring of the radial bearing and the inner end surface of the bearing holding recess, and the tips are inserted into the recesses of the wave washer. It is characterized in that a plurality of stopper projections are provided on the inner end surface of the bearing holding recess.

In this case, the wave washer may be provided with an escape recess corresponding to the stopper protrusion.

[0017]

As described above, the wave washer is arranged between the end surface of the outer ring of the radial bearing and the inner end surface of the bearing holding recess, and the tips are inserted into the plurality of recesses of the wave washer so that the inner end surface of the bearing holding recess is inserted. If a plurality of stopper projections are provided on the ridge, the wave washer can be prevented from sagging without increasing the number of parts.

In this structure, since the stopper projection is provided near the outer periphery of the bearing holding recess, the inner diameter of the shaft through hole of the stator supporting cylinder can be increased. Therefore, it is possible to perform the cutting process of the two bearing holding recesses without exchanging the chuck, to prevent misalignment, to improve the processing accuracy, and to reduce the processing man-hour.

If the wave washer is provided with an escape recess,
Each stopper protrusion is preferable because it does not restrict the normal operation of the wave washer.

[0020]

1 (A) (B) -FIG. 3 shows a first embodiment in which the present invention is applied to the brushless DC motor described above.

In the brushless DC motor of this embodiment, the end face of the outer ring 12b of the radial bearing 12 in the bearing holding recess 10 and the inner end face 10a of the bearing holding recess 10 are formed.
A wave washer 14 is arranged between the two. A plurality of stopper projections 19 are projected on the inner end surface 10a of the bearing holding recess 10 by inserting the tips into the recesses 14a of the wave washer 14.

The other structure is similar to that of FIG. 6 described above.

As described above, the wave washer 14 is arranged between the end surface of the outer ring 12b of the radial bearing 12 and the inner end surface 10a of the bearing holding recess 10, and the tips are inserted into the recesses 14a of the wave washer 14. A plurality of stopper projections 19 are formed on the inner end surface 10a of the bearing holding recess 10.
By projecting, the settling of the wave washer 14 can be prevented without increasing the number of parts. That is, when these stopper protrusions 19 are present, the push-cutting due to an external force in the axial direction is stopped by these stopper protrusions 19 via the wave washer 14, and the settling of the wave washer 14 can be prevented.

In this structure, since the stopper projection 19 is provided near the outer periphery of the bearing holding recess 10, the inner diameter d2 of the small diameter hole portion 8a of the shaft through hole 8 of the stator supporting cylinder portion 1 can be increased. Therefore, it is possible to cut the bearing holding recess 10 with a cutting tool, and then pass the cutting tool through the small diameter hole 8a to cut the bearing holding recess 11 on the opposite side. Therefore, the cutting processing of the two bearing holding recesses 10 and 11 can be performed without exchanging the chuck, and the misalignment does not occur.
The processing accuracy can be improved and the processing man-hour can be reduced.

4A and 4B and 5A and 5B
Shows a second embodiment in which the present invention is applied to the brushless DC motor described above.

In the brushless DC motor of this embodiment, the recesses 20 are provided in the wave washer 14 so as to correspond to the stopper protrusions 19.

The other structure is shown in FIG.
(B) to FIG. 3 and FIG.

When the relief recess 20 is provided in the wave washer 14 in this way, each stopper projection 19 does not restrict the normal operation of the wave washer 14, and is thus preferable.

In the above embodiment, an example in which the present invention is applied to a brushless DC electric motor has been described, but the present invention is not limited to this and can be applied to other rotary electric machines in the same manner. .

[0030]

As described above, according to the rotating electric machine of the present invention, the following excellent effects can be obtained.

In the present invention, a wave washer is arranged between the end surface of the outer ring of the radial bearing and the inner end surface of the bearing holding recess, and the tip of the wave washer is inserted into the recesses of the wave washer so that the inside of the bearing holding recess. Since a plurality of stopper protrusions are provided on the end face, it is possible to prevent the wave washer from sagging without increasing the number of parts.

In particular, according to the present invention, since the stopper projection is provided near the outer periphery of the bearing holding recess, the inner diameter of the shaft through hole of the stator supporting cylinder can be increased. Therefore, it is possible to perform the cutting process of the two bearing holding recesses without exchanging the chuck, to prevent misalignment, to improve the processing accuracy, and to reduce the processing man-hour.

If the wave washer is provided with an escape recess, each stopper projection is preferable because it does not restrict the normal operation of the wave washer.

[Brief description of drawings]

FIG. 1A is a front view of a bearing holding concave portion provided in a stator supporting cylinder portion in a first embodiment of a rotating electric machine according to the present invention;
(B) is a vertical sectional view of (A), and (C) is a sectional view taken along the line AA of (A).

FIG. 2 is a vertical cross-sectional view showing a state in which a radial bearing and a wave washer are incorporated in a bearing holding recess in the first embodiment.

FIG. 3 is a vertical cross-sectional view showing the relationship between a wave washer and a stopper protrusion arranged in a bearing holding recess in the first embodiment.

FIG. 4A is a vertical cross-sectional view showing a relationship between a wave washer and a stopper projection in a bearing holding recess provided in a stator supporting cylinder in a second embodiment of the rotating electric machine according to the present invention;
(B) is a longitudinal sectional view showing a state in which a radial bearing is incorporated in the bearing holding recess in the structure of (A).

5A is a front view of the wave washer used in the second embodiment, and FIG. 5B is a vertical cross-sectional view of FIG.

FIG. 6 is a vertical cross-sectional view of a brushless DC electric motor as a conventional rotating electric machine.

7A is a front view of a bearing holding recess provided in a stator supporting cylinder of a conventional rotating electric machine, and FIG. 7B is a vertical sectional view of FIG. 7A.

FIG. 8 is a vertical cross-sectional view showing a state in which a radial bearing and a wave washer are incorporated in a bearing holding recess in a conventional rotating electric machine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stator support cylinder part 2 Stator 3 Rotor 4 Stator core 5 Stator coil 6 Cup-shaped yoke 7 Permanent magnet 8 Shaft through hole 8a Small diameter hole part 9 Rotating shaft 10,11 Bearing holding recess 10a Inner end surface 12,13 Radial bearing 12a, 13a Inner Ring 12b, 13b Outer ring 12c, 13c Steel ball 14 Wave washer 15 Printed circuit board 16 Fixing part 17 Insulating spacer 18 Stopper part 19 Stopper protrusion 20 Escape recess

Claims (2)

[Claims] 1. A stator is mounted on the outer circumference of a stator support cylinder, a rotor is rotatably arranged on the outer circumference of the stator, and a rotary shaft is passed through a shaft through hole of the stator support cylinder. It is rotatably supported by radial bearings arranged in bearing holding recesses on both sides in the longitudinal direction of the stator support tubular portion, and at least one of the radial bearings absorbs a play in the axial direction of the rotary shaft. In a rotary electric machine in which a wave washer is arranged and the rotor is supported on the rotating shaft, the wave washer is arranged between an end surface of an outer ring of the radial bearing and an inner end surface of the bearing holding recess, A rotary electric machine characterized in that the tip is inserted into a plurality of recesses of the wave washer, and a plurality of stopper projections are provided on the inner end surface of the bearing holding recess. . 2. The rotating electric machine according to claim 1, wherein the wave washer is provided with an escape recess corresponding to the stopper protrusion.