JPS6037012Y2 - Field core fixing structure of small electric motor - Google Patents

Description

[Detailed description of the invention] The present invention relates to a structure for fixing a bracket and a field core in a small electric motor.The width of the bracket only needs to be the straight part outside the field core, which significantly reduces the amount of bracket material. The purpose of this invention is to easily and reliably fix the bracket and the field core.

Conventionally, the bracket and the field core were fixed as shown in Fig. 1 and Fig. 2.
This was done by press-fitting a field core into a cylindrical bracket 1' as shown in the figure.

However, with this configuration, the shape of the bracket is large and extra material is required, and the strength of the positioning protrusion and interference must be considered when press-fitting the field core. .

SUMMARY OF THE INVENTION In view of the above-mentioned drawbacks, the present invention aims to provide a structure for fixing a field core to a bracket that improves this problem.

3 and 4 show the shape of the bracket. 1 is a bracket made of steel plate, 1a is a press-formed positioning convex part that forms a connection part with a field core, which will be described later, and 5th
As shown in the figure, two grooves are provided parallel to each other in the axial direction, and the gap between the grooves is bent as shown in FIG. 8 so as to protrude inward.

In addition, in FIG. 5, a indicates the dimension between the grooves before providing the positioning convex portion 1a, and in FIG. 8, b indicates the dimension between the grooves after providing the positioning convex portion 1a. It is in.

Moreover, FIGS. 6 and 7 show the groove shapes when forming the positioning convex portion 1a, and FIG. 6 shows a groove in which a groove connecting two grooves is further formed. The figure shows two grooves with both ends extending in the direction of the opposing grooves.
In order to facilitate the formation of the positioning convex portion 1a, the groove shape is modified, but basically two grooves are provided in parallel in the axial direction.

FIG. 9 shows the configuration of the field core, where 2 is a field core formed by laminating a plurality of iron plates, 2a is a recess that fits into the bracket positioning convex 1a, and field core 2 is It is provided on the outer surface of the.

Moreover, FIGS. 10 and 11 show the shape of the recess 2a. In FIG. 10, the opening end of the recess 2a is formed to have a smaller diameter than the bottom, and FIG. 11 shows the shape of the recess 2a. The dimensions of the open end and the bottom are the same.

In FIG. 10, C indicates the width of the recess 2a that fits into the positioning projection 1a of the bracket 1.

Further, FIG. 12 shows a state in which the convex portion 1a and the concave portion 2a are fitted together.

From this state, as shown in FIG.
The bracket 1 and the field core 2 are positioned and fixed by making the bent portions flat.

However, in this case, the relationship between dimensions a, b, and c is a
> c > b.

FIG. 14 shows a state in which the field core 2 is fixed to the bracket 1 as described above and the motor is assembled.

As described above, the fixing structure of the bracket and field core of a small electric motor of the present invention is such that the bent convex part of the bracket is inserted into the concave part of the field core, and the bent part of the convex part is flattened. It is positioned and fitted with the field core, and there is no need for press-fitting the field core, so the amount of bracket material can be significantly reduced, and it can be fixed easily and reliably, among other benefits. is obtained.

[Brief explanation of drawings]

FIG. 1 is a front half-sectional view showing a conventional bracket for a small electric motor, FIG. 2 is a side view of FIG. 1, and FIG. 3 is a front half-sectional view showing a bracket for a small electric motor according to an embodiment of the present invention. Figure 4 is a side view of Figure 3, Figure 5 is a side view of Figure 3, and Figure 5 is a side view of Figure 3.
3, FIGS. 6 and 7 are views taken along arrow A in FIG. 3 showing other embodiments, FIG. 8 is a sectional view taken along line B-B in FIG. The figure is a front view of the field core of the electric motor, FIG. 10 is an enlarged view of section D in FIG. 9, and FIG.
The figure is an enlarged view of part D showing another embodiment, FIG. 12 is an enlarged view of the above electric motor when the bracket convex part and the field core concave part are fitted together, and FIG. 13 is the above bracket convex part and the field core concave part. FIG. 14 is an enlarged view of the case where the core recesses are fitted and the protrusions are flattened and fixed, and FIG. 14 is a perspective view of a small electric motor according to an embodiment of the present invention. 1... Bracket, 1a... Fitting portion with field core and bent convex portion for positioning, 2
......Field core, 2a...Recess that fits into the protrusion of the bracket, a...Dimension between grooves in bracket 1 before providing the protrusion, b... ...Groove dimension after providing the convex part in bracket 1, C...
...Width dimension of the recess 2a of the field core 2 that fits into the bracket protrusion.

Claims (1)

[Scope of utility model registration request] Two grooves are provided in the steel plate bracket parallel to the axial direction, and the space between the grooves is bent in a curved shape in a direction perpendicular to the axis so as to fit into a recess provided on the outer surface of the field core. Field core fixing for a small electric motor, in which a convex part protruding from the field core is formed, the curved convex part is fitted into a concave part of the field core, and the bent part of the convex part is flattened to fix the field core and the bracket. structure.