JP3121496B2 - Motor detent device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor detent device for a power tool having an external carbon brush.

[0002]

2. Description of the Related Art A conventional motor detent device will be described with reference to FIGS. FIG. 3 is a side view showing a conventional motor detent device, and FIG. 4 is a sectional view taken along line BB of FIG. 3 and 4, a carbon brush tube 3 (hereinafter referred to as a CB tube) accommodating an external carbon brush 2 (hereinafter referred to as a carbon brush).
The motor case 1 is provided with an end cap 4 at one end of the motor case 1 and an inner cover 5 at the other end. A plurality of holes are formed in the end cap 4, and four screws 6 are inserted into the holes. The inserted screws 6 are screwed into respective screw grooves formed in the inner cover 5. As described above, the rotation of the motor in the related art is performed by the four screws 6.

[0003]

Generally, the outer appearance of the motor case is cylindrical, and therefore has few flat portions. For this reason, it is troublesome to stop the motor from rotating by holding the motor case in two. That is, it is difficult to reliably support the curved surface and stop the rotation of the motor. Therefore, in order to surely prevent the rotation of the motor, a plurality of screws are screwed into the screw grooves formed in the inner cover by tapping. Therefore, there is a problem that the manufacturing cost is increased by performing the tapping, and the number of parts increases because the rotation of the motor is stopped using a plurality of screws.

An object of the present invention is to provide a simple motor detent device that reduces the manufacturing cost of the motor detent device.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a motor case having a hole through which a CB tube is inserted, wherein a projection is formed on the motor case and a holding portion for holding the projection is provided in a split housing. Is achieved in.

[0006]

In the motor detent device constructed as described above, the reaction force of the motor is reduced by holding the convex protrusion formed on the motor case by the holding portion provided in the housing. And act to receive at the clamping portion.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a side view showing a motor detent device according to the present invention, and FIG. 2 is a sectional view taken along line AA of FIG.

In FIGS. 1 and 2, a motor case 1 for accommodating a motor is provided in a split housing 7, 8, and an end cap 4 having a bearing portion 4a is provided at one end of the motor case 1. At the same time, an inner cover 5 is provided at the other end. The motor case 1 is provided with a hole into which the CB tube 3 is inserted, and a plurality of convex protrusions 1a extending along the outer periphery of the CB tube 3 (in the direction perpendicular to the amateur axis). The rotation of the motor case 1 is prevented by clamping the convex protrusion 1a by a plurality of clamping portions 7a, 8a formed in the split housings 7, 8. That is, the projection 1a and the holding portion 7
The rotation of the motor is stopped by the frictional resistance of the holding parts 7a, 8a, and the reaction force of the motor is held by the holding parts 7a,
8b. Further, an elastic body (not shown) made of rubber or the like is provided in the split housings 7 and 8 to restrict movement of the motor case 1 in the axial direction (in the direction of the amateur axis). The elastic body is disposed, for example, at both ends of the motor case 1. When the motor case 1 is housed in the split housings 7 and 8, the motor case 1 elastically deforms the elastic body. . For this reason,
The axial movement of the motor case 1 can be restricted by the restoring force of the elastic body. Further, this elastic body also has a role of a damper that can reduce impact to the motor and the like.

In the present invention, the rotation of the motor is stopped by the above-described structure. At the same time, the rotation of the motor is more reliably stopped by holding the opposite end cap 4 side of the motor between the housings 7 and 8. Can be.

[0010]

According to the present invention, the projecting projections are formed on the motor case, and the projecting projections are clamped by the clamping portions formed on the split housing, thereby reducing the manufacturing cost of the motor detent device. And a simple motor detent device can be provided.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of a motor detent device according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a side view showing a conventional motor detent device.

FIG. 4 is a sectional view taken along line BB of FIG. 3;

[Explanation of symbols]

1 is a motor case, 1a is a convex protrusion, 2 is a carbon brush, 3 is a CB tube, 7 is a split housing, 7a
Is a holding portion, 8 is a split housing, and 8a is a holding portion.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-6-237557 (JP, A) JP-A-6-233490 (JP, A) Japanese Utility Model Application Sho 55-181463 (JP, U) Japanese Utility Model Utility Model Sho 62- 132267 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) H02K 5/00

Claims (1)

(57) [Claims] A motor detent comprising a carbon brush, a carbon brush tube for accommodating the carbon brush, a motor case into which the carbon brush tube is inserted, and a split housing for accommodating the motor case. The apparatus according to claim 1, wherein a convex protrusion extending along an outer periphery of the carbon brush tube is formed on the motor case, and the convex protrusion is held by a holding portion formed on the split housing. Stop device.