JPH11230182A - Bearing holding mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a simple structured bearing holding mechanism by integrally forming a bearing housing and plural projections. SOLUTION: A recessed shaped bearing housing 2 for storing a sliding bearing 5 and plural projections 3 which extends from an opening of the bearing housing 2 and prevents the sliding bearing 5 from falling from the bearing housing 2 are integrally formed with resin. The sliding bearing 5 is inserted into a space formed by the bearing housing 2 and the projections 3, and a pressing spring 6 for pressing the sliding bearing is mounted at the top of the projections 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sliding bearing holding mechanism for supporting a rotating shaft such as a rotor of a motor.

[0002]

2. Description of the Related Art As an example using a conventional sliding bearing holding mechanism, a brushless DC motor which is one of motors will be described with reference to FIG. FIG. 5 is a side sectional view of a conventional brushless DC motor.

In FIG. 5, a motor frame 15 comprises a cylindrical stator 17 around which a winding 16 is wound, and a winding connection board 18 mounted adjacent to the stator 15 with a resin 19. Is formed in a cylindrical shape.

[0004] The brushless DC motor 20 is housed in the inner peripheral portion of the motor frame 15 and has a rotor 22 to which a permanent magnet 21 is attached, two slide bearings 24 supporting a shaft 23 of the rotor 22, and A bearing housing 25 is provided at both openings of the motor frame 15 to accommodate the sliding bearings 24.

[0005] The bearing housing 25 is provided with a sliding bearing 2.
4 is housed, and the sliding bearing 24 is pressed and fixed,
And a holding spring 26 for providing self-aligning action,
A felt 27 impregnated with lubricating oil for reducing friction between the shaft 23 of the rotor 22 and the slide bearing 24 is provided, and a felt storage portion 28 for storing the felt 27 is provided.

[0006] The sliding bearing 24 is usually formed of a sintered oil-impregnated alloy.
When the amount of the lubricating oil during the period 3 decreases, the lubricating oil is supplied from the felt 27 to prevent wear of the sliding bearing 24 or the shaft of the rotor 22 to extend the life.

[0007]

In the conventional motor constructed as described above, as described above, a bearing housing and a holding spring are required to provide a sliding bearing with a self-aligning action. After the sliding bearing is housed in the bearing housing, an operation of fixing the bearing housing and the pressing spring, for example, an operation of press-fitting, caulking, etc., has been required.

In addition, a storage portion for storing a felt material or the like impregnated with lubricating oil around the bearing has to be constituted by an iron plate or the like.

[0009]

Therefore, according to the present invention, a concave bearing housing for accommodating a sliding bearing and extending from an opening of the bearing housing to prevent the sliding bearing from dropping from the bearing housing. A plurality of protrusions to be formed are integrally formed of resin, a slide bearing is inserted into a space formed by the bearing housing and the protrusion, and a holding spring for pressing the slide bearing is attached to a tip of the protrusion. The present invention provides a bearing holding mechanism characterized in that:

[0010]

The bearing holding mechanism having a simple structure can be formed by integrally molding the bearing housing and the plurality of projections with resin.

Further, the noise caused by resonance is reduced by integrally forming the motor frame and the bearing holding mechanism and supporting the motor shaft with a sliding bearing.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. 1 to 4 taking a brushless DC motor as an example.
FIG. 1 is a front view of a motor frame formed integrally with a bearing holding portion according to the present invention. FIG. 2 is a side sectional view of the motor frame of FIG. 1 as viewed from section AA.
FIG. 3 is a side sectional view illustrating a process of inserting a slide bearing into the motor frame of FIG. FIG. 4 is a side sectional view of the brushless DC motor according to the present invention.

1 and 2, the motor frame 1 is formed in a cup shape from resin. A concave bearing housing 2 is formed at the center of the bottom of the motor frame 1. A plurality of projections 3 are formed from the opening of the concave bearing housing 2. A groove 4 is provided on the outer peripheral surface of the tip of the projection 3 for attaching a pressing spring described later.

That is, the motor frame 1 is provided with a bearing holding mechanism formed by the bearing housing 2 and the projection 3,
It is formed integrally with resin.

In FIG. 3, a sliding bearing 5 is inserted into a space defined by a bearing housing 2 and a projection 3 of a motor frame 1 and temporarily fixed. Then, the holding spring 6 is attached to the groove 4 provided at the tip of the projection 3.

The sliding bearing 5 is a resin bearing which is filled with lubricating oil and has a structure in which the lubricating oil exudes to the contact surface of the rotor with the shaft, thereby extending the life of the motor. be able to.

Further, the pressing spring 6 is attached to the groove 4 at the tip of the projection 3, and the tip of the projection 3 is focused toward the center of the shaft, thereby pressing the outer peripheral surface of the slide bearing 5 with a certain force. And fix it.

The shape of the surface of the bearing housing 2 and the projection 3 which comes into contact with the outer peripheral surface of the slide bearing 5 after the holding spring 6 is attached is such that the slide bearing 5 can have self-centering.

In FIG. 4, a brushless DC motor 7
Is an outer frame formed by laminating two types of cup-shaped motor frames 1 and 8 integrally formed with the bearing housing 2 and the projections 3 described above, and is fixed to the inner peripheral surface of the outer frame, A cylindrical stator 10 wound with a coil 9, a rotor 12 housed in an inner peripheral portion of the stator 10 and having a permanent magnet 11 attached thereto, and a shaft 13 of the rotor 12 are supported. Two sliding bearings 5 housed in housing 2
It is composed of

As described above, the motor frame and the bearing holding mechanism are integrally formed of resin, and the sliding bearing is also formed of resin, so that a highly silent motor can be constructed.

Further, if the motor may be shorter than the life of the motor described in the above embodiment and there is no strict requirement for noise, the sintered oil-impregnated alloy sliding bearing described in the conventional example may be used. May be used.

[0022]

According to the present invention, the bearing holding mechanism can be constructed at low cost and with simple assembly work.

Further, when used as a bearing holding mechanism for a motor, a motor with reduced noise due to resonance can be provided.

[0024]

[Brief description of the drawings]

FIG. 1 is a front view of a motor frame formed integrally with a bearing holding portion according to the present invention.

FIG. 2 is a side sectional view of the motor frame of FIG. 1 as viewed from section AA.

FIG. 3 is a side sectional view illustrating a process of inserting a slide bearing into the motor frame of FIG. 1;

FIG. 4 is a side sectional view of a brushless DC motor according to the present invention.

FIG. 5 is a side sectional view of a conventional brushless DC motor.

[Explanation of symbols]

 1, 8, 15 ... motor frame 2, 25 ... bearing housing 3 ... projection 4 ... groove 5, 24 ... sliding bearing 6, 26 ... holding spring 7, 20 ... brushless DC motor 9, 16 ... winding 10, 17 ... fixed Element 11, 21 ... permanent magnet 12, 22 ... rotor 13, 23 ... axis 18 ... substrate 19 ... resin 27 ... felt 28 ... felt resin

Claims (1)

[Claims] 1. A concave bearing housing for accommodating a sliding bearing, and a plurality of protrusions extending from an opening of the bearing housing and preventing the sliding bearing from dropping from the bearing housing, are integrally formed of resin. A bearing holding mechanism, wherein a sliding bearing is inserted into a space formed by the bearing housing and the projection, and a holding spring for pressing the sliding bearing is attached to a tip of the projection.