JPH0370445A - Means for supporting bearing of rotating machine - Google Patents

Abstract

PURPOSE:To enable using an apparatus both for preventing the backlash of an outer ring and for applying a pre-load to a bearing through a pre-load spring by inserting the pre-load spring providing a part of the outer periphery of an annular plate having a corrugated section with a bending part for radially performing a spring action between the stepped part of the inner periphery and the inner peripheral end of a bearing housing and the outer ring. CONSTITUTION:The outer ring 2a of a ball bearing 2 fitted into a rotating shaft 1 is loose-fitted to the inner periphery of a cylindrical bearing housing 14a, and an elastic pre-load spring 20 is suitably compressed and inserted between the stepped part 14b of the inner periphery and the inner peripheral end of the bearing housing 14a and the outer ring 2a. The pre-load spring 20 is formed by the bias-working of a spring steel plate and a part of the outer periphery of an annular plate having a corrugated section is provided with a bending part 20a for radially performing a spring action. Thus, a simple structure with a small number of required parts enables preventing the backlash of the outer ring 2a of the ball bearing 2 loose-fitted to the inner periphery of the bearing housing 14a and applying a pre-load to the bearing 2.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention is a bearing support device for a rotating machine in which the outer ring of a ball bearing is loosely fitted to the inner periphery of a bearing housing. This invention relates to a device that allows the addition of a simple structure with a small number of required parts.

[Conventional technology]

A conventional example of a bearing support device for a rotating machine will be explained based on the longitudinal cross-sectional view of FIG. FIG. 3 shows an outer rotor type motor, in which a rotating shaft 1 is supported on the inner periphery of a cylindrical bearing housing 4a provided at the center of a fixed bracket 4 via a pair of ball bearings 2.3.

A cylindrical stator core 5 is fitted on the outer periphery of the bearing housing 4a, and a cylindrical rotor 6 made of a permanent magnet or the like and surrounding the stator core 5 is rotated through a rotating bracket 7 that supports it. It is supported at the end of the rotating shaft l. The rotating bladder 7 is fitted onto the rotating shaft 1 by a cylindrical boss 7a provided at the center, and the boss 7a has an end surface that comes into contact with the inner ring end surface of one of the bearings 2, so that it also serves to position the bearing 2. It has become. In the bearing 2, the outer ring 2a is a bearing housing 4a.
The inner circumference of the bearing housing 4a is loosely fitted to the inner circumference of the bearing housing 4a, and between the inner circumference of the bearing housing 4a and the outer ring 2a, there is a radial groove in order to eliminate rattling of the outer ring 2a due to the clearance and to prevent the rotating shaft 1 from swinging due to vibration etc. Spring action is performed to move the outer ring 2a into the bearing housing 4a.
A leaf spring 8 that presses against the inner periphery of the bearing housing 4a is attached to the end face of the bearing housing 4a with bolts 9 and inserted. Also, outer ring 2a
and the stepped portion 4 at the center of the inner circumference of the bearing housing 4a.
An elastic preload spring 10 having an annular wave-shaped cross section that performs a spring action in the axial direction is appropriately compressed and inserted between the bearings 1 and 2b, thereby applying pressure to the bearings 2 and 3.

The preload spring 10 applies preload to the bearings 2 and 3 to reduce noise generated from the bearing 23 during rotation and to prevent damage to the bearings 2 and 3 due to vibration.

[Problem to be solved by the invention]

However, in the above structure, the leaf spring 8 and the preload spring 10 are used to prevent rattling of the outer ring 2a and to apply preload to the bearings 2 and 3, which not only increases the number of required parts but also reduces assembly work. This method requires a lot of work and has the disadvantage that the motor becomes larger due to the space required for attaching the leaf spring 8 to the bearing housing 4a.

In order to eliminate the above-mentioned drawbacks, this invention prevents rattling of the outer ring of a ball bearing loosely fitted to the inner periphery of a bearing housing and applies preload to the bearing using a simple structure with a small number of required parts. An object of the present invention is to provide a bearing support device for a rotating machine that enables the following.

[Means to solve the problem]

In order to achieve the above object, the bearing support device for a rotating machine of the present invention includes an annular plate with a corrugated cross section between the inner periphery of the cylindrical bearing housing, the stepped part of the inner periphery end, and the outer ring of the ball bearing. A preload spring is inserted in a part of the outer periphery, which has a bent part that acts as a spring in the radial direction.

[Effect]

The bent portion of the preload spring presses the outer ring of the ball bearing against the inner periphery of the bearing housing to prevent rattling, and the axial spring action can apply preload to the bearing;
This also allows for a simpler structure by reducing the number of required parts.

〔Example〕

FIG. 1 is a vertical sectional view showing an embodiment of the present invention, and FIG.
Components indicated by the same reference numerals as those in the figures are the same parts. In FIG. 1, the outer ring 2a of the ball bearing 2 fitted on the rotating shaft 1 is loosely fitted to the inner periphery of a cylindrical bearing housing 14a, and the stepped portion 14b on the inner periphery and the inner periphery end of the bearing housing 14a is shown.
An elastic preload spring 20 is appropriately compressed and inserted between the outer ring 2a and the outer ring 2a. The preload spring 20 is formed by pressing a spring steel plate, and as shown in the perspective view of FIG. 2, a bent portion 20a that exerts a spring action in the radial direction is provided on a part of the outer periphery of an annular plate with a corrugated cross section. It is being This bent portion 20a is formed by a gap between the outer ring 2a and the inner circumference of the bearing housing 14a.
This is to eliminate rattling and prevent the rotating shaft 1 from swinging due to vibrations, etc., and the outer ring 2a is pressed against the inner circumference of the bearing housing 14a by a radial spring action.

In addition, the annular plate having a corrugated cross section of the preload spring 20 is used to reduce the noise generated by the bearing 2 due to rotation by applying preload to the bearing 2, and to prevent damage to the bearing 2 due to vibration. The action presses the outer ring 2a to apply preload. The end face of the inner ring of the bearing 2 abuts against the end face of a cylindrical boss 7a at the center of a rotating bracket 7 fitted onto the end of the rotating shaft 1, thereby determining its axial position.

According to the embodiment described above, the preload spring 20 with a bent portion serves both to prevent rattling of the outer ring 2a and to apply preload to the bearing 2, so the number of required parts is reduced and assembly work is facilitated. Also, the bolt 9 of the leaf spring 8 explained in the conventional example
The attachment to the bearing housing 4a can reduce the size of the rotating machine by the amount of space required.

In the embodiment described above, the annular plate of the preload spring 20 has a corrugated cross section, but it is also possible to use an annular disc spring.

〔Effect of the invention〕

According to the present invention, in a bearing support device for a rotating machine in which the outer ring of a ball bearing is loosely fitted to the inner periphery of a bearing housing, a corrugated cross section is formed between the inner periphery of the bearing housing and the stepped portion at the end of the inner periphery and the outer ring. Since a preload spring is inserted in a part of the outer periphery of the annular plate, the preload spring is used to prevent rattling of the outer ring and to apply preload to the bearing. This has the effect of simplifying the structure with fewer required parts.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a main part of an embodiment of the present invention, FIG. 2 is a perspective view of the preload spring shown in FIG. 1, and FIG. 3 is a longitudinal sectional view of a conventional example. DESCRIPTION OF SYMBOLS 1...Rotating shaft, 2.3...Ball bearing, 2a...Outer ring, 4...Fixing bracket, 4a...Bearing housing, 5...Stator core, 6...Rotor , 7... Rotating bracket, 7a... Cylindrical boss, 8... Temporary spring,
9... Bolt, 10... Preload spring, 14a... Bearing housing, 14b... Stepped portion, 20... Preload spring, 20a... Bent portion. Figure 3

Claims (1)

[Claims] 1) A spring acts in the radial direction on a part of the outer circumference of the annular plate with a corrugated cross section between the inner circumference of the cylindrical bearing housing that loosely fits the outer ring of the ball bearing, and the stepped part of the inner circumference end and the outer ring. A preload spring provided with a bent portion for performing this is inserted, and the preload spring presses the outer ring against the inner periphery of the bearing housing,
A bearing support device for a rotating machine characterized by applying preload to the bearing by pressing with an axial spring action.