JPH0334296B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in the structure of a brush holder used in an electric motor.

Conventionally, the structure of a brush holder that holds a brush that slides against a commutator, which is a rectifier, is as follows.
In most cases, a plurality of brush holders that hold individual brushes are fixed to a single plate, and this plate is fixed with screws or the like from outside the frame that is fixed to the yoke. In contrast, today there is a trend toward manufacturing electric motors by integrally molding the brush holder and plate from resin in order to reduce the weight of the device itself.

The brush storage portion of this resin brush holder is open only in the radial direction, which is the direction in which the brush is pressed, and is designed to restrict brush movement up and down in the axial direction of the armature, and left and right in the rotational direction of the armature. . However, in order to mold a brush holder having such a shape, it is necessary to provide a cylindrical space for the brush storage portion, which makes the mold complicated and difficult to manufacture.

In view of the above-mentioned problems, the present invention opens one side of the brush storage part in the axial direction and arranges an insulator for regulating the movement of the brush in the axial direction in this open part, thereby creating a brush holder that is easy to mold. It is intended for the purpose of providing.

The present invention will be described below with reference to embodiments shown in the drawings. FIG. 1 is a cross-sectional view of a motor in which a brush holder according to the present invention is assembled, FIG. 2 is a cross-sectional view along line A-A in the axial direction of FIG. 1, and FIG. 3 is a cross-sectional view of a protruding portion of a frame. 1 is a yoke provided with a stepped portion 1a extending inward from the end surface; 2 is a frame having a protruding portion 2a protruding inwardly at the bottom; the inner diameter matches the stepped portion 1a; 3 is a cylindrical commutator 3a. It is an armature with FIG. 4 is a perspective view of the brush holder of the present invention, and FIG. 5 is a plan view of the insulator. The brush holder 4 is integrally molded from resin, and a storage section 4a for storing the brush 5 is provided on a plate section 5b with one side open in the radial direction, which is the pressing direction of the brush 5, and one side in the axial direction, and is used for positioning and It has a notch 4c for drawing out the brush lead wire. 6
is an insulator that is positioned by the storage part 4a of the brush holder 4 and the positioning notch 6a, and which restricts the axial displacement of the brush 5 by the brush holding part 6b. come into contact with 7 is a brush spring that presses the brush 5 toward the commutator 3a, and 8 is a through bolt that clamps and fixes the yoke 1 between the frame 2 and a housing (not shown).

Next, the operation of the above configuration will be explained. The brush holder 4 stores the brush 5 in the storage part 4a and connects the commutator 3 with the brush spring 7 in the radial direction.
a, and the movement of the brush 5 is regulated by an insulator 6 in the axial direction. Since the dimension B from the stepped part 1a to the bottom of the frame 2 in FIG. 1 is larger than the dimension C from the stepped part 1a to the protruding part 2a in FIG. 3, when the through bolt 8 is tightened and fixed,
The protruding part 2a of the frame 2 comes into contact with the separation part 6c of the insulator 6 and is bent, and this elasticity allows the brush holder 4, brush 5, and insulator 6 to be held between the yoke 1 and the frame 2 and fixed in the axial direction. .

In this way, the brush holder 4 can be easily molded because the shape of the storage part 4a is simplified, and the number of parts can be reduced because there is no need to fix the frame 2 from outside with screws, etc. Furthermore, since the brush holder 4 is made of resin, the number of parts can be reduced. It also becomes possible to reduce the weight.

Other embodiments of the present invention include the following.

As shown in FIG. 6, the arrangement of the brush holder 4 and the insulator 6 is changed, and
The brush holder 4 and the insulator 6 may be sandwiched by providing a convex portion 1b that comes into contact with the separation portion 6c of the insulator 6 in addition to a.

Alternatively, as shown in FIG. 7, the brush holder 4 and the insulator 6 may be arranged interchangeably, and the brush holder 4 may be provided with a separation portion that comes into contact with the protruding portion 2a of the frame 2.

Furthermore, as shown in FIG.
A wave-shaped washer 9 as shown in FIG. 9 may be inserted between the yoke 1 and the frame 2, and the brush holder 4 and the insulator 6 may be held between the yoke 1 and the frame 2 by the elasticity of the wave-shaped washer 9.

As described above, according to the present invention, one side of the brush housing portion of the brush holder in the axial direction is opened, and an insulator for regulating the movement of the brush in the axial direction is disposed in this open portion. Since the shape of the housing part is simple, molding is easy, and since there is no need to fix the frame from outside, it has the excellent effect of reducing the number of parts.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a motor in which a brush holder according to the present invention is assembled, and FIG. 2 is a cross-sectional view of a motor in the axial direction of FIG.
-A sectional view, Fig. 3 is a sectional view of the protruding part of the frame, Fig. 4 is a perspective view of the brush holder, Fig. 5 is a plan view of the insulator, and Figs. This is another embodiment of the invention. 1... Yoke, 2... Frame, 2a... Protrusion, 3... Armature, 3a... Commutator,
4... Brush holder, 4a... Storage section, 5... Brush, 6... Insulator, 6c... Separation section.

Claims (1)

[Scope of Claims] 1. In a plurality of brush holders that are held between a yoke of an electric motor and a frame fixed to the yoke and slide in opposition to a commutator integrated with an armature, the plurality of housing portions of the brushes are arranged on one side in the axial direction. 1. A brush holder characterized in that an annular insulator is disposed in the open portion, and an annular insulator for regulating the movement of all the brushes in the axial direction. 2. The brush holder according to claim 1, wherein the annular insulator has an elastic portion that prevents the insulator from rattling.