JPS5821326Y2 - micro motor - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a micromotor that simultaneously fixes an L-shaped plate-like brush body attached to the bottom surface of the motor case by coupling a bottomed cylindrical motor case and a bracket that covers the opening of the motor case.

In the conventional device, the motor case and the bracket are connected separately from the installation and fixing of the brush body, and the brush body uses a wedge, and the brush mounting part has a special structure.
- Therefore, the brush mounting work must be done carefully, and the fixing of the brush body and the bracket must be done separately, resulting in a large number of assembly steps and high costs.

The present invention has been devised in view of these points, and one embodiment thereof will be described below with reference to the drawings.

In Fig. 1, 1 is a cylindrical resin motor case with a bottom, and its opening is a resin platen that fits into the opening edge step 2).
3, and a field section and an armature 4 are housed inside the motor case 1.

Reference numeral 5 designates a yoke member, which is constructed by bending a belt-shaped thick steel plate into a ring shape having a pair of straight portions A and a pair of circular arc portions, and is placed on the stepped portion 6 of the motor case 10.

An arcuate permanent magnet 7 is attached to the inner surface of the opening of the circular arc portion, and one end of each permanent magnet 7 is attached to a protrusion 8 provided on the inner surface of the straight portion A.
A U-shaped wire spring 9 is stretched between the other ends of each permanent magnet 7, and the yoke member 5 is expanded and fixed to a rib 10 provided on the inner wall of the motor case 1 under pressure.

Further, the armature shaft 11 is supported by bearings 12 and 13 fixed to the motor case 1 and the bracket 3.

The L-shaped plate-shaped brush body 15 that comes into sliding contact with the commutator 14 is attached below the straight portion A of the yoke member 5 as follows.

That is, as shown in FIG. 3, the brush body 15 is formed in an L-shape having a connecting base end piece 16 and a brush piece 17, and the connecting base end piece 16 is connected to a through hole 19 bored in the bottom surface 18 of the motor case 1.
inserted into.

Further, the elastic portion 20 provided on the connecting base end piece 16 is press-fitted into the through hole 19, and the brush body 15 is temporarily fixed.

In this case, the rear part 21 of the brush piece 17 comes into contact with a protrusion 22 provided at the edge of the through hole 19.

On the other hand, a protrusion 23 is provided on the inner surface of the bracket 3 and has a length that reaches the bottom surface 18 of the motor case 1 when the bracket is fitted into the opening edge step 2 of the motor case 1. A lower end step portion 24 is formed at.

The tip of this protrusion 23 reaches the bottom surface 18 of the motor case 1 through the gap between the straight part A of the yoke member 5 and the inner wall of the motor case 1, and the lower end step 24 is connected to the rear part 2 of the brush piece 17.
It engages with the protrusion 22 via.

In this state, the bracket 3 and the motor case 1 are coupled by screwing the screws 26 through the through holes 25 provided in the motor case 1.

Note that the tip of the protrusion 23 does not necessarily have to reach the bottom surface 18 of the motor case 1, and it is not necessary to connect the bracket 3 and the motor case 1 at the bottom surface 18 of the motor case 1. For example, they may be connected at the opening edge step 2 of the motor case 1 using screws or adhesive.

As described above, according to the configuration of the present invention, the connecting base end piece of the L-shaped plate-shaped brush body is inserted into the through hole bored in the bottom of the bottomed resin cylindrical motor case, and is fitted into the opening edge of the motor case. The brush body is held between the lower end of the protrusion provided on the lower surface of the mating resin bracket and the protrusion provided on the edge of the through hole on the bottom surface when the motor case and the bracket are connected. The brush body will be fixed at the same time as the bracket is fixed.

The brush body can be simply inserted into the through hole in the connecting base end piece, and there is no need to provide a wedge or a complicated structure for the brush attachment part as in conventional devices. motor can be provided.

[Brief explanation of drawings]

The drawing shows an embodiment of a micromotor according to the present invention,
FIG. 1 is a sectional view of the micromotor, FIG. 2 is a plan view of the motor case, FIG. 3 is a partially enlarged oblique view of the brush mounting portion, and FIG. 4 is a sectional view of the main part during assembly. 1...Motor case, 18...Bottom surface,
19...Through hole, 3...Bracket, 2
3... Projection pillar, 16... Connection base end piece, 1
5...Brush body, 22...Protrusions.

Claims (1)

[Scope of utility model registration request] A through hole is bored in the bottom of the resin bottomed cylindrical motor case, and a protrusion is provided on the inner surface of the resin bracket that fits into the opening edge of the motor case, and the connecting proximal end piece is inserted into the through hole. Further, an L-shaped plate-shaped brush body, in which an elastic portion provided on the connection base end piece is press-fitted into the through-hole, is provided at the lower end of the protrusion and the edge of the through-hole by fixing the bracket. A micromotor, characterized in that the brush body is fixed by clamping the rear part of the brush piece of the brush body with protrusions.