JP3030568U - DC motor - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a DC motor having a structure capable of improving workability when press-fitting a bearing of a rotary shaft or covering a yoke. A stator (2) is provided on the inner circumference of a bottomed cylindrical yoke (1).
Is assembled in an annular shape, and the rotor 3 is rotatably incorporated in the stator 2. The cover 7 is attached so as to close the opening of the yoke 1. The rotating shaft 4 of the rotor 3 is rotatably supported by a bearing 8 fitted to a fitting portion 1b provided on the bottom 1a of the yoke 1 and a bearing 9 fitted to a fitting portion 7a provided on the cover 7. The brush plate 10 is sandwiched and fixed by the locking portion 11 provided on the yoke 1 and the cover 7. The brush plate 10 and the cover 7 are provided with an engaging portion 17 including a concave portion 15 and a convex portion 16 that are fitted in the rotating shaft 4 in the axial direction.

Description

[Detailed description of the device]

[0001]

[Technical field to which the device belongs]

 The present invention relates to an improvement of a DC motor of a type in which a brush plate is sandwiched and fixed by a locking portion provided on a yoke and a cover that closes an opening of the yoke.

[0002]

[Prior art]

 FIG. 3 shows the structure of a conventional DC motor of this type. In the DC motor, a stator 2 made of a permanent magnet is annularly assembled to the inner periphery of a bottomed cylindrical yoke 1, and a rotor 3 is rotatably incorporated in the stator 2. The rotor 3 includes a rotor core 5 fixed to the outer circumference of the rotary shaft 4 and a rotor coil 6 wound around the rotor core 5. A cover 7 is attached to the yoke 1 so as to close its opening. Although not shown, the cover 7 is attached to the yoke 1 by caulking. The rotating shaft 4 of the rotor 3 is a bearing 8 fitted and supported by a fitting portion 1b provided on the bottom portion 1a of the york 1, and a bearing press-fitted and fixed to a fitting portion 7a provided on the cover 7. 9 and 9 are press-fitted and fixed, and are rotatably supported. A brush plate 10 is arranged in a direction parallel to the cover 7, and the brush plate 10 is fixed by being sandwiched between two or more locking portions 11 provided by stamping on the yoke 1 and the cover 7. A brush (not shown) is supported on the brush plate 10, and the brush is in contact with the commutator 12 on the rotor 3 side. The brush plate 10 is integrally provided with a terminal holder 13, and the terminal holder 13 is fitted into a hole 14 provided in the cover 7 and is led out to the outside. A terminal connected to the brush is supported by the terminal holder 13.

In this case, in the brush plate 10, the stepped portion 13a of the terminal holder 13 contacts the cover 7, and the leg portion 10a of the brush plate 10 contacts the cover 7 so that the distance from the cover 7 is maintained. There is.

To assemble such a DC motor, the bearing 9 is press-fitted and fixed to the fitting portion 7a of the cover 7, and the brush plate 10 is fitted to the rotary shaft 4 of the rotor 3, In this state, the rotary shaft 4 of the rotor 3 is press-fitted into the bearing 9 to position the rotor 3, and then the yoke 1 having the stator 2 is put on the rotor 3 and the yoke 1 is swaged to the cover 7. By.

[0005]

[Problems to be solved by the device]

 However, in such a conventional DC motor, the position is not fixed because the brush plate 10 can move freely until the work of crimping the yoke 1 to the cover 7 is completed, and the rotary shaft 4 is set to the bearing 9. There was a problem in that workability was poor when press-fitting or when covering the yoke 1.

An object of the present invention is to provide a DC motor having a structure capable of improving workability when press-fitting a rotary shaft into a bearing or covering a yoke.

[0007]

[Means for Solving the Problems]

 According to the present invention, the stator is annularly assembled to the inner circumference of the bottomed cylindrical yoke, the rotor is rotatably incorporated in the stator, and the cover is attached so as to close the opening of the yoke. The shaft is rotatably supported by a bearing fitted to a fitting part provided on the bottom of the yoke and a bearing fitted to a fitting part provided on the cover, and a shaft provided on the yoke. This is to improve a DC motor having a structure in which a brush plate is sandwiched and fixed by a stopper and a cover.

In the DC motor according to the first aspect of the present invention, the brush plate and the cover are provided with an engaging portion including a concave portion and a convex portion which are fitted in the axial direction of the rotating shaft.

As described above, when the brush plate and the cover are provided with the engaging portion including the concave portion and the convex portion that are fitted in the axial direction of the rotating shaft, the brush plate is temporarily locked to the cover first by the engaging portion. By setting it in advance, the position of the brush plate is determined, and workability when press-fitting the rotary shaft into the bearing or covering the yoke can be improved. Further, in the case of this structure, no additional parts such as screws are required for positioning, which is advantageous in cost.

In the DC motor according to the second aspect of the present invention, the engaging portion is provided with a protrusion provided on the brush plate, a recess provided on a tip surface of the protrusion, and a protrusion provided on the cover. It is characterized in that it is composed of a convex portion that fits into a concave portion of the tip end surface of the protruding portion.

[0011]

[Embodiment of device]

 1 and 2 show an example of an embodiment of a DC motor according to the present invention.

In the DC motor of this example, the brush plate 10 and the cover 7 are provided with an engaging portion 17 including a concave portion 15 and a convex portion 16 each of which is a hole fitted in the rotating shaft 4 in the axial direction. There is. The engaging portion 17 of this example includes a protruding portion 18 protruding from the brush plate 10, a recess 15 provided on the tip surface of the protruding portion 18, and a protruding portion 18 protruding from the cover 7. It is composed of a convex portion 16 that fits into the concave portion 15 of the tip surface. The convex portion 16 is formed by stamping.

In assembling such a DC motor, the bearing 9 is press-fitted into the fitting portion 7a of the cover 7 and fixed, and the protrusion 15 protruding from the brush plate 10 is provided with a concave portion 15 on the tip end surface thereof. The protrusion 16 of the cover 7 is fitted to temporarily fix the brush plate 10 to the cover 7, and in this state, the rotary shaft 4 of the rotor 3 is press-fitted into the bearing 9 to position the rotor 3, and then the rotor 3 is positioned. This is done by covering the rotor 3 with the yoke 1 provided with the stator 2 and crimping the yoke 1 on the cover 7.

As described above, by temporarily engaging the brush plate 10 with the cover 7 by the engaging portion 17, the position of the brush plate 10 is determined, and the rotary shaft 4 is press-fitted into the bearing 9 or the yoke 1 is pressed. It is possible to improve the workability when covering. Further, in the case of this structure, no additional parts such as screws are required for positioning, which is advantageous in terms of cost.

It should be noted that the concave portion 15 and the convex portion 16 are not limited to circular shapes and may be rectangular shapes, or one may be circular and the other may be rectangular.

In contrast to the present example, the concave portion 15 and the convex portion 16 may be provided in the cover 7 via the protruding portion 18 and the convex portion 16 may be provided in the brush plate 10.

[0017]

[Effect of device]

 In the DC motor according to the present invention, since the brush plate and the cover are provided with the engaging portion composed of the concave portion and the convex portion which are fitted in the axial direction of the rotating shaft, the brush plate is first covered by the engaging portion. The position of the brush plate can be determined by temporarily locking the brush plate, and the workability when press-fitting the bearing of the rotary shaft and covering the yoke can be improved. Further, in the case of this structure, a new component such as a screw is not required for positioning, which is advantageous in cost.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an example of an embodiment of a DC motor according to the present invention.

FIG. 2 is an enlarged cross-sectional view of a main part of this example.

FIG. 3 is a vertical sectional view of a conventional DC motor.

[Explanation of reference numerals] 1 yoke 1a bottom portion 1b fitting portion 2 stator 3 rotor 4 rotating shaft 5 rotor core 6 rotor coil 7 cover 7a fitting portion 8 bearing 9 bearing 10 brush plate 10a leg portion 11 locking portion 12 commutator 13 Terminal holder 13a Stepped portion 14 Hole 15 Recessed portion 16 Convex portion 17 Engagement portion 18 Protruded portion

Claims (2)

[Scope of utility model registration request] 1. A stator is annularly assembled to an inner circumference of a bottomed cylindrical yoke, a rotor is rotatably incorporated in the stator, and a cover is attached so as to close an opening of the yoke. The rotating shaft of the rotor is rotatably supported by a bearing fitted to a fitting portion provided on the bottom of the yoke and a bearing fitted to a fitting portion provided on the cover. A DC motor in which a brush plate is sandwiched and fixed by a locking portion provided on the cover and the cover, wherein the brush plate and the cover include a concave portion and a convex portion that are fitted in the axial direction of the rotating shaft. A direct-current motor characterized in that an engaging portion is provided. 2. The engaging portion includes a protrusion provided on the brush plate, a recess provided on a tip surface of the protrusion, and a protrusion provided on the cover and provided on a tip surface of the protrusion. The DC motor according to claim 1, wherein the DC motor is configured with a convex portion that fits in a concave portion.