JPH0116367Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to an electric motor equipped with a thrust bearing.

Conventional technology As a conventional thrust bearing,
There is one disclosed in the publication No. First, this conventional example will be explained with reference to FIGS. 1 and 2.

FIG. 1 is a perspective view showing a conventional thrust bearing, and FIG. 2 is a longitudinal cross-sectional view of an electric motor showing a state in which the thrust bearing is engaged with a bearing support. 1st
As shown in the figure, the thrust bearing 1 is formed into a crown shape using a resin such as polyacetal that can form a surface having a sliding bearing effect. Reference numeral 2 denotes a cylindrical body, and the cylindrical body 2 is formed with a receiving surface 4 for supporting an end portion of the rotating shaft 3. Reference numeral 5 denotes a plurality of protrusions formed on the side 6 opposite to the receiving surface 4, which are formed to expand from the outer diameter of the cylindrical body 2 and extend integrally from the cylindrical body 2. Reference numeral 7 denotes a pushing protrusion, which inserts the thrust bearing 1 into the insertion hole 9 of the bearing support part 8 of the housing.
It has a flat surface for applying pushing pressure when it is inserted into the housing, and is parallel to the receiving surface 4 and the upper surface of each protrusion 5. This pushing protrusion 7 is also a cylindrical body 2.
However, as shown in FIG. 2, if the thrust bearing 1 is made to protrude to the outside of the bearing support part 8, the thrust bearing 1 can be inserted without using any special tools. If a tool such as a push rod is used, there is no particular need to provide the push-in protrusion 7, and it is sufficient to push the side 6 opposite to the receiving surface 4 with a push rod or the like for insertion. The degree of expansion of the protrusion 5 is as follows:
The outer peripheral edge of the protrusion 5 is expanded to a slightly larger diameter than the diameter of the insertion hole 9 of the bearing support part 8, and the cylindrical body 2 is
The outer diameter of the insertion hole 9 may be slightly smaller than the diameter of the insertion hole 9. Further, the connecting portion between the projections 5 and the cylindrical body 2 is selected to have a shape that is relatively flexible outwardly.

Next, a method for attaching this thrust bearing 1 to the bearing support portion 8 will be explained.

The structure of the bearing support part 8 is as shown in FIG.
It has a substantially cylindrical shape and holds the radial bearings 10 and 11 within the cylinder. The load in the thrust direction is applied in the direction of the arrow in the figure, and the radial bearings 10 and 11 have no bearing effect against the load in the thrust direction.

An annular groove 12 is provided on the cylindrical inner surface of the bearing support portion 8 using a boring machine or the like. The depth of the annular groove 12 may be such that the tip of the protrusion 5 can be attached thereto;
If it is an electric motor used for audio equipment, etc., the thickness should normally be around 1 mm. The cross-sectional shape of the annular groove 12 does not have to be the shape shown in FIG. 2, as long as the jaws forming the locking portion can be secured, and for example, the cross-sectional shape may be triangular.

Now, if the thrust bearing 1 is inserted into the bearing support part 8 formed as described above through the insertion hole 9 before or after inserting the rotating shaft 3, in the direction opposite to the thrust load direction, that is, the thrust direction. , protrusion 5
... is once bent inward in the insertion hole 9, inserted, expands outward at a predetermined position, and is engaged with the jaws of the annular groove 12 at the locking portion, thereby fixing the thrust bearing 1. .

A problem with the conventional example described above is that the thrust bearing 1 rotates as the rotating shaft 3 rotates, which accelerates the wear of the thrust bearing 1 and adversely affects the wow performance of the motor.

For this reason, in the past, an epoxy adhesive or the like was applied to the thrust bearing 1 to prevent rotation, but this work was very time-consuming and the adhesive flowed, causing the adhesive to flow onto the bearing 10 side. This caused the motor to malfunction.

Purpose of the invention The purpose of the invention is to solve the problem of the prior art, that is, to prevent rotation of the thrust bearing.

Composition of the invention The present invention has been made to achieve the above-mentioned purpose and is constructed as follows. That is, in the present invention, the thrust bearing is made of resin and has a cylindrical body, and the cylindrical body has an outer diameter large enough to fit into the through hole of the bearing support part, and has a plurality of uneven parts on the lower outer periphery. A thrust receiving surface is formed on the lower end surface, and a plurality of protrusions are formed on the outer peripheral surface.
The plurality of protrusions have elasticity and expand from a small diameter dimension fitted into the through hole to a large diameter dimension larger than the through hole, and the thrust bearing is fitted at the tip of the through hole and has a plurality of projections. The protrusion is attached to the attachment part, the plurality of uneven parts are in contact with the inner circumferential wall of the through hole, and the thrust receiving surface is in contact with the tip of the rotating shaft. .

Embodiment An embodiment of the present invention will be described with reference to FIGS. 3 to 5.

In these figures, reference numeral 13 denotes a bearing support portion of the housing 14, which is formed from aluminum die casting. Further, the lower end of this bearing support portion 13 is fixed to a support plate 16 of a coil 15 formed of an iron plate. A through hole 13a through which the rotating shaft 17 is inserted is bored in the bearing support portion 13, and radial bearings 18, 19 are fixedly installed in the through hole 13a. The rotating shaft 17 is rotatably inserted into the radial bearings 18 and 19. The thrust bearing 20 is fitted into the engaging portion 13b formed near the open end of the through hole 13a. This thrust bearing 20 is made of polyacetal resin and has a cylindrical body 20c. The cylindrical body 20c has an outer diameter large enough to be fitted into the through hole 13a, and a plurality of uneven portions 20d are formed on the lower outer periphery. A thrust receiving surface 20b is formed on the lower end surface, and a plurality of protrusions 20a are formed on the outer peripheral surface. The plurality of protrusions 20a have elasticity and expand from a small diameter dimension that is fitted into the through hole 13a to a large diameter dimension that is larger than the through hole 13a. The plurality of uneven portions 20d are formed by knurling or the like.

When the thrust bearing 20 is fitted into the tip of the through hole 13a, the plurality of protrusions 20a are engaged with the engaging portion 13b, and the plurality of uneven portions 20d are brought into contact with the inner circumferential wall of the through hole 13a, thereby preventing the rotation of the thrust bearing 20. Prevented.
In this case, the thrust receiving surface 20b is
is brought into contact with the tip of the Rotation of the thrust bearing 20 is prevented.

Effects of the invention As explained above, according to the invention, the rotation of the thrust bearing can be prevented by simply fitting the thrust bearing into the bearing support part without using adhesive, which improves work efficiency. Cost reduction can be achieved.

Furthermore, since no adhesive is used, the thrust bearing can be easily replaced, which has great practical effects.

[Brief explanation of the drawing]

1 and 2 are a perspective view of a conventional thrust bearing and a vertical sectional view of an electric motor equipped with this bearing, and FIGS. 3 to 5 show an embodiment of the present invention, and FIGS. FIG. 4 is a perspective view and a half-sectional side view showing the thrust bearing, and FIG. 5 is a longitudinal sectional view of the electric motor showing a state in which the thrust bearing is engaged. 13...Bearing support part, 13a...Through hole, 14...
...Housing, 17...Rotating shaft, 20...Thrust bearing, 20a...Protrusion, 20b...Thrust receiving surface, 20c...Cylindrical body, 20d...Irregular portion.

Claims (1)

[Claims for Utility Model Registration] An electric motor having a housing 14, a thrust bearing 20, and a rotating shaft 17, wherein the housing 14 has a bearing support part 13, and the bearing support part 13 has a through hole 13a. , through hole 13
A has an engaging part 13b formed at its tip, a thrust bearing 20 made of resin, and a cylindrical body 20.
The cylindrical body 20c has an outer diameter large enough to fit into the through hole 13a, a plurality of uneven parts 20d are formed on the lower outer periphery, and a thrust receiving surface 20b is formed on the lower end surface. A plurality of protrusions 20a are formed on the outer circumferential surface, and the plurality of protrusions 20a have elasticity, and the through-hole 1
The rotating shaft 17 is rotatably supported by the bearing support part 13, and the thrust bearing 20 is inserted into the through hole 13a. The plurality of protrusions 20a are fitted to the tip, and the plurality of protrusions 20a are attached to the attachment portion 13b, the plurality of uneven portions 20d are brought into contact with the inner circumferential wall of the through hole 13a, and the thrust receiving surface 20b is brought into contact with the tip of the rotating shaft 17. An electric motor characterized in that it is