JPH0534212Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a brush device for a DC motor in which a brush is clamped and fixed between a brush holder and a bond magnet.

[Prior art]

Conventionally, the brush fixing structure of a normal DC motor has a dimensional margin in the axial direction of the motor, so a groove 9a and a hole 9b are formed in a thick synthetic resin brush holder 9 as shown in Fig. 7. The terminal portion 5a was press-fitted into the hole so that the brush 5 could be inserted into the hole.
Since flat type motors have dimensional restrictions, the terminal portion 6d may be press-fitted into the hole 18a of a thin synthetic resin brush holder 18 as shown in FIG.
A structure is adopted in which a protrusion 18b is provided at the terminal portion, and a hole in the terminal portion is fitted into the protrusion 18b for welding. Both have weak strength, so if the terminal part is protruded to the outside, a considerable amount of force and heat will be applied, which may cause the brush position to shift or make sliding contact with the commutator unstable. To avoid this, a lead wire is connected to the terminal and pulled out to prevent direct application of large force or heat to the terminal. but,,
When lead wires are used, there is an increase in the number of types due to differences in length, wire diameter, etc., and there is also the disadvantage that workability is extremely reduced.

[Purpose of invention]

In view of the above-mentioned drawbacks, the present invention proposes a brush device for a DC motor that uses the pressure of fixing the side plate to the stator case by caulking and press-fitting to increase the fixing strength of the terminal part and improve workability.

[Structure of the idea]

In the present invention, a stator is constructed by disposing a bonded magnet in a stator case, an armature having a commutator is opposed to the bonded magnet, and a side plate is attached to the stator case to provide a brush that slides in contact with the commutator. In the DC motor fixed to a brush holder, the terminal portion of the brush is clamped and fixed between the brush holder and the bond magnet.

〔Example〕

The present invention will be explained below with reference to illustrated embodiments. 1st
In Figures 2 and 2, the magnets constituting the stator are elastic members using bonded magnets, which are resin-bonded magnets, and the brush holder itself, which is fixed to the side plate attached to the stator, is elastic. The first embodiment is made of a synthetic resin material, and the terminal portion of the brush is clamped and fixed between the brush holder fixed to the side plate and the stator case via the bond magnet, and the brush device of the DC motor is cup-shaped. An elastic bond magnet 2 is fitted and fixed into the stator case 1, and a side plate 3 is fixed to the upper side of the stator case 1 in the drawing by caulking or press fitting. A brush holder 4 made of resin is fixed to the inside of the side plate 3 by screws or resin molding. The brush holder 4 has a protrusion 4
A is formed, the hole of the terminal portion 5a of the brush 5 is fitted, and the protrusion 4a is positioned and fixed by thermally deformed welding. Window hole 1a in stator case 1
is formed, and the terminal portion 5a protrudes to the outside.

Bearings 10 and 11 are fixed to the center of the bottom surface of the stator case 1 and the center of the brush holder 4, and a rotating shaft 12 of the armature 6 is supported thereon. The armature 6 has an armature core 1 in which a coil 13 is wound around a rotating shaft 12.
4 and a commutator unit 15 are fitted together. The commutator unit 15 has a sliding contact portion 5 of the brush 5.
b is in sliding contact. A collar 16 is fitted onto the rotating shaft 12 below the armature core 14.

The brush device of the DC motor is configured as described above, and the side plate 3 has the brush holder 4 and the brush 5 fixed thereto.
is fixed to the stator case 1 by caulking or press-fitting, the terminal part 5a is fixed using this fixing pressure.
hits the upper surface of the elastic bonded magnet 2 and is pressed and clamped and fixed.

Therefore, even if a considerably large force or heat is applied to the terminal portion 5a, since it is clamped and fixed by the bond magnet 2, which is an elastic member, and the brush holder 4, the position will not shift, and the performance of the motor will not deteriorate. Furthermore, since the terminal portion 5a protrudes to the outside, there is no need to connect lead wires to the terminal portion inside the stator case in advance, thereby improving work efficiency.

FIG. 5 shows a modified example in which the terminal portion 5a is positioned in the elastic brush holder 8, and the sharp bent protrusion 5c formed on the terminal portion 5a is press-fitted into the elastic brush holder 8. . Other methods of positioning may also be used.

[Effect of idea]

In this invention, when the side plate is fixed to the stator case by caulking or press-fitting, this fixing pressure is used to move the terminal part of the brush positioned inside the side plate via the brush holder to the terminal part of the brush, which is attached to the stator case by a bond magnet or the like. The terminal part, which is clamped and fixed via an elastic member or an elastic member such as an elastic brush holder, and which protrudes from the stator case to the outside, will not shift position even if large force or heat is applied, improving the performance of the motor. DC motors have excellent practical effects such as improved workability and improved workability since the terminals protrude outside and there is no need to connect the lead wires to the terminals inside the stator case in advance. A brush device can be provided.

[Brief explanation of drawings]

1 to 6 show embodiments of the brush device for the DC motor of the present invention, and FIGS. 1 and 2 show the first embodiment, FIG. 1 is a cross-sectional side view of the DC motor, and FIG. 2 is a cross-sectional side view of the DC motor. Fig. 3 is an enlarged sectional side view of the main part of the second embodiment, Fig. 4 is an enlarged sectional side view of the main part of the third embodiment, and Fig. 5 shows the terminal part of the brush attached to the brush holder. Sectional side view of a modified example of positioning, No. 6
The figure is an enlarged cross-sectional side view of the main part of the fourth embodiment, FIG. The figure is a cross-sectional side view of the main part showing the structure for fixing the terminal part of the brush of a conventional flat type motor to the brush holder. Figure 9 is a cross-sectional view of the main part showing the structure for fixing the terminal part of another brush to the brush holder. FIG. 1... Stator case, 2, 2', 2''... Magnet, 2, 7, 8... Elastic member, 3... Side plate,
5... Brush, 4a... Terminal section, 6... Armature, 15... Commutator unit.

Claims (1)

[Scope of utility model registration request] A stator is constructed by disposing a bonded magnet in the stator case, an armature having a commutator is opposed to the bonded magnet, and a brush that comes into sliding contact with the commutator is fixed to a brush holder on a side plate attached to the stator case. A brush device for a DC motor, wherein a terminal portion of the brush is clamped and fixed between the brush holder and the bond magnet.