JPH07135751A - Brush device of small sized motor and its manufacture - Google Patents

Abstract

PURPOSE:To provide the brush device of a small sized motor which facilitates the elimination of troublesome works such as the welding between terminal pieces and brush pieces and the press-fitting of a brush base into grooves and provides a uniform distance between a pair of the brush pieces. CONSTITUTION:A pair of brush pieces which have brush contact pieces 7b and 8b on their one side ends and coil connection pieces 7c and 8c on the other side ends are molded in a brush base 20 by insert-molding while the respective brush contact pieces 7b and 8b and coil contact pieces 7c and 8c are exposed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brush device for a small motor and a method for manufacturing the brush device.

[0002]

2. Description of the Related Art In a conventional brush device for a small motor, a pair of plate terminals for coil connection, one end of which is bent and fixed by welding, is prepared. It was pressed into the groove and fitted.

[0003]

However, according to such a conventional method, the terminal piece, the brush piece, and the brush base are divided into three parts.
Since the points are created separately, they are assembled, so the assembly work such as welding of the terminal piece and brush piece, press fitting into the groove of the brush base, etc. is extremely complicated, especially with a brush device with a very small small motor. Met.

In the case of an ultra-small size, the brush piece is extremely small, thin, and easily deformed by an external force, so that the assembly work is difficult, and the brush piece is easily deformed during handling such as preparation and transportation as a single item, and its handling is extremely complicated.

Since a pair of brush pieces are welded to the terminal pieces and press-fitted into the grooves 4 of the brush base 3,
If the uniformity of the mounting posture and the uniformity of the press-fitting posture are not extremely high due to welding, it is difficult for the spacing between the pair of brush pieces to be constant, which makes it difficult to make the crimping force on the commutator uniform. Lacked stability.

It is an object of the present invention to provide a brush device for a small motor and a method for manufacturing the brush device, which solves these problems.

[0007]

In order to solve the above problems, in a brush device for a small motor of the present invention, a pair of brush pieces having a brush contact piece at one end and a coil connecting piece at the other end. Is insert-molded on the brush base in a state where the brush contact pieces and the coil connection pieces are exposed.

In the method for manufacturing a brush device for a small motor according to the present invention, the metal plate material is punched out, and the brush contact piece is provided on one end side and the brush contact piece is provided on the other end side in a state where the intermediate portion is connected to the metal plate material by the connecting portion. A punching step of forming a pair of brush pieces having a coil connection piece, a processing step of processing the brush contact piece and the coil connection piece of the pair of brush pieces into a predetermined shape on one side of the metal plate material, and the pair of A bending step of bending the brush piece toward the opposite surface side of the metal plate at the connecting portion so that the pair of brush pieces face each other, and the brush contact piece and the coil connecting piece expose the pair of brush pieces to the outside. And an insert molding step of insert-molding the brush base, and a cutting step of cutting the pair of brush pieces from the metal plate material at the connecting portion.

[0009]

According to the present invention, since the brush contact portion and the coil connecting portion of the brush piece are integrally formed and the brush base is insert-molded, the assembly is complicated. No work is required, and the spacing between the pair of brush pieces is uniform.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS. 15 and 16, the brush device of the present invention includes a pair of brush pieces 7 and 8 having brush contact pieces 7 on one end side.
b, 8b and the coil connecting pieces 7c, 8c are exposed to the outside from the side wall step portions of the support columns 20b, 20c of the brush base 20, and a space S (see FIG.
3)), a pair of brush pieces 7, 8 is formed.
Is insert-molded on the brush base 20 made of plastic. The coils 30a and 30b are connected to the coil connecting pieces 7c and 8c by welding or soldering.

Next, a method of manufacturing the brush device of the present invention will be described. As shown in FIG. 1, a thin strip plate-shaped metal plate material 2 having contact side cladding layers 1a and 1b provided on one surface side is provided with positioning holes 3a and 3b provided on both sides at equal intervals.
First, while sequentially feeding in the direction of the arrow,
As shown in FIG. 2, the holes 4a, 4b, 4 are formed by pressing.
c and 4d are punched out, the slits 5a, 5b, 6a and 6b are punched out as shown in FIGS. 3 and 4, and the punching is further performed as shown in FIG. 5, so that the intermediate portions 7a and 8a are connected portions 9 and 10, respectively.
The brush contact pieces 7b, 8b on one end side and the coil connection pieces 7c, 8c on the other end side in a state of being connected to the metal plate 2 by
Forming a pair of brush pieces 7 and 8 which are parallel to each other and in which the brush contact pieces 7b and 8b are staggered. Each brush contact piece 7b and 8b is branched into three by the slits 5a, 5b and 6a, 6b.

Next, while sequentially feeding the metal plate material 2, the both ends of each brush piece 7, 8 are placed on one side of the metal plate material 2 as shown in FIGS. 6 and 7 (upper surface as shown in FIG. 7). Side) and press it into a predetermined shape with the upper and lower molds and bend it.

Next, while sequentially feeding the metal plate material 2, the opposite side of the metal plate material 2 at the boundary lines 7d and 8d (see FIG. 6) between the connecting portions 9 and 10 and the brush piece intermediate portions 7a and 8a. The pair of brush pieces 7 and 8 are opposed to each other by bending at a right angle (as shown in FIG. 9) to the lower surface side.

Then, as shown in FIG. 10, the metal plate material 2 is intermittently fed in sequence and horizontally clamped from both sides of the metal plate material 2 toward the center by a die to brush the brush pieces 7, 8. The contact pieces 7b and 8b are bent into a predetermined shape in which they are closely parallel to each other and face each other.

Before and after these bending processes, the connecting portions 9 and 10 are provided with the cut lines 11 and 12 shown in FIGS.

Next, the metal plate material 2 is fed into a molding machine (not shown), and as shown in FIGS. 11 to 14, a plastic molding is made up of a disc portion 20a and a pair of support portions 20b, 20c on the upper surfaces of both sides thereof. The brush base 20 is formed by the method described above. In this molding, the pair of brush pieces 7 and 8 are replaced by the brush contact pieces 7b and 8b and the coil connection pieces 7c and 8c.
b, 20c, the brush contact pieces 7b, 8b and the coil connection, which are exposed outward from the intermediate portions 7a, 8a and the connecting portions 9, 10 so that the tips of the intermediate portions 7a, 8a and the connecting portions 9, 10 are buried in the support columns 20b, 20c. Between the lower end surfaces of the pieces 7c and 8c and the upper surface of the disk portion 20a of the brush base 20, slide from both sides in the horizontal direction (the direction parallel to the paper surface from the top and bottom in FIG. 11) to form the space S. The brush base 20 is molded from plastic with the mold entering.

The connecting portions 9 and 10 are composed of support columns 20b and 20c.
Are exposed to the outside in the notches 21 and 22 on the outer circumference of the upper end of the brush contact pieces 7b and 8b and the coil connecting piece 7c
8c is exposed to the outside at the step of the side wall of the support columns 20b and 20c.

In the center of the disk portion 20a of the brush base 20, there is a hole 23 in which the commutator of the motor and the shaft are located.
Are provided, and coil insertion holes 24a and 24b are provided on both sides thereof.
Is provided.

After molding, at the cuts 11 and 12 provided in the connecting portions 9 and 10, as shown in FIG.
The coil 3 into the coil insertion holes 24a and 24b.
0a, 30b are inserted and connected to the coil connecting pieces 7c, 8c of the brush pieces 7, 8 by soldering. In FIG. 16, reference numeral 31 is a connector.

The present invention is not limited to the above embodiment, and it is needless to say that various modifications can be made.
For example, the shape of the brush piece obtained by punching a metal plate is shown in FIG.
However, the present invention is not limited to the above and can be arbitrarily changed.

[0021]

As described above, according to the present invention, since (a) the brush contact piece and the coil connecting piece are integrated, the separate brush piece and terminal piece are connected by welding as in the prior art. In addition, since the brush base and the brush piece are integrally formed by insert molding, there is no need to press-fit and assemble into a groove of a separate brush base as in the conventional case. No need for complicated assembly work by parts. Therefore, the production efficiency is remarkably increased, and the cost can be significantly reduced.

(B) In particular, this is remarkable in the manufacture of a very small brush device, and in the present invention, the brush device is produced while the minute thin and easily deformable brush piece is connected to the metal plate material. It eliminates the complexity of handling a brush piece which is easily deformed as in the conventional case as an assembly part.

(C) In the present invention, a pair of brush pieces are formed into a completely constant shape by punching, bending, etc.,
Since it is insert-molded on the brush base with the shape as it is, the distance between the pair of brushes is always constant, so that the crimping force to the commutator can be made uniform and the stability of the product is significantly improved.

[Brief description of drawings]

FIG. 1 is a plan view showing a manufacturing method of the present invention.

FIG. 2 is a plan view showing the manufacturing method of the present invention.

FIG. 3 is a plan view showing the manufacturing method of the present invention.

FIG. 4 is a plan view showing the manufacturing method of the present invention.

FIG. 5 is a plan view showing the manufacturing method of the present invention.

FIG. 6 is a plan view showing the manufacturing method of the present invention.

7 is a sectional view taken along line AA in FIG.

FIG. 8 is a plan view showing the manufacturing method of the present invention.

9 is a sectional view taken along line BB in FIG.

FIG. 10 is a plan view showing the manufacturing method of the present invention.

FIG. 11 is a plan view showing the manufacturing method of the present invention.

FIG. 12 is a perspective view of FIG.

13 is an enlarged cross-sectional view taken along line CC of FIG.

14 is an enlarged cross-sectional view taken along line DD in FIG.

FIG. 15 is a plan view showing a brush device of the present invention.

FIG. 16 is a left side view showing a part of the brush device of the present invention in a cutaway section.

[Explanation of symbols]

 2 Metal plate materials 7, 8 Brush pieces 7a, 8a Intermediate part 7b, 8b Brush contact pieces 7c, 8c Coil connecting piece 9, 10 Connecting part 20 Brush part 20a Disc part 20b, 20c Strut part

Claims (2)

[Claims] 1. A small size of a pair of brush pieces having a brush contact piece on one end side and a coil connecting piece on the other end side, insert-molded on a brush base in a state where the brush contact piece and the coil connecting piece are exposed. Motor brush device. 2. A punching process in which a metal plate material is punched to form a pair of brush pieces having a brush contact piece on one end side and a coil connection piece on the other end side in a state where an intermediate portion is connected to the metal plate material by a connecting portion. A step of processing the brush contact piece and the coil connection piece of the pair of brush pieces into a predetermined shape on one surface side of the metal plate material, and the pair of brush pieces on the opposite surface of the metal plate material at the connecting portion. A bending step of bending the pair of brush pieces to face each other, and an insert molding step of insert-molding the pair of brush pieces into a brush base so that the brush contact piece and the coil connection piece are exposed outward; A method of manufacturing a brush device for a small motor, comprising a step of separating the pair of brush pieces from the metal plate material at the connecting portion.