JPH05111208A - Electric motor bearing device - Google Patents

Abstract

(57) [Abstract] [Object] An object of the present invention is to prevent the impregnated lubricating oil from escaping to the outside of the bearing holder due to an increase in internal pressure during sliding of an oil-impregnated bearing in an electric motor, thereby extending the service life thereof. .. [Structure] A bearing device for an electric motor according to the present invention includes a stator 22.
The fixed end side opening of the cylindrical bearing holder 23 fixed to the frame 20 and having the oil-impregnated bearing 28 fitted therein is closed by the thrust receiving plate 40. The motor rotating shaft 2 having the opening on the opposite side of the bearing holder 23 supported by the oil-impregnated bearing 28.
9 is airtightly closed by a lid 30 that is airtightly inserted, and the opposite side is extended and the end thereof is bent toward the motor rotating shaft 29 side, and the lid 30 is used as a bottom for filling with oil and fat. Part 2
7 is formed and the oil 31 is filled. According to the present invention, the oil and fat prevent the impregnated lubricating oil from leaking out of the bearing holder due to the increase in the internal pressure of the oil-impregnated bearing during operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing device for an electric motor, such as an axial fan, which supports a motor rotating shaft using an oil-impregnated bearing fitted in a bearing holder attached to a frame of a stator. is there.

[0002]

2. Description of the Related Art FIG. 3 is a sectional view showing a conventional electric motor disclosed in Japanese Utility Model Publication No. 55-117160, in which 1 is a frame of a stator 3 and 2 is a bearing holder provided on the frame. 4, a stator core, 5 windings wound on the stator core, 6 an oil-impregnated bearing fitted in the bearing holder,
Reference numeral 7 is a motor rotating shaft supported by the oil-impregnated bearing, 8 is a retaining member attached to an end of the motor rotating shaft protruding from the oil-impregnating bearing 6, and 9 is a slip washer superposed on the retaining member. Reference numeral 10 denotes a rotor having a magnet 11 fixed to the other end of the motor rotating shaft 7, and 12
Is a sealing plate on the fixed end side of the bearing holder 2.

[0003]

In the conventional motor bearing device having the above structure, the internal pressure of the oil-impregnated bearing 6 rises due to the load during operation, and the impregnated lubricating oil (hereinafter referred to as oil) oozes out on the surface. .. Further, the temperature of the oil-impregnated bearing 6 rises due to the heat generation of the stator core 4, which also causes an increase in the internal pressure and promotes the exudation of oil. The oil flowing out from the sliding surface of the oil-impregnated bearing is transmitted through the motor rotating shaft 7 and the bearing holder 2
Is transmitted to the outer surface of the bearing holder 2 or the rotor 10. Then, the oil once flowing out there cannot return to the oil-impregnated bearing 6 again. Therefore, there is a problem that the oil in the oil-impregnated bearing 6 is reduced and the rotation speed is lowered or the starting failure occurs.

The present invention has been made to solve the above problems, and prevents the impregnated oil from escaping out of the bearing holder due to the increase of the internal pressure of the oil-impregnated bearing during the operation to extend the life thereof. This is intended to be achieved.

[0005]

A bearing device for an electric motor according to the present invention includes a cylindrical bearing holder having one end fixed to a frame of a stator, and a motor rotating shaft supported in the bearing holder. An oil-impregnated bearing and a lid that airtightly penetrates the motor rotation shaft and airtightly seals the other end opening of the bearing holder, and extends the other end of the bearing holder, An oil and fat filling portion having the lid as a bottom is formed by bending the motor rotation shaft side, and the oil and fat filling portion is filled with oil and fat.

Further, an annular recess is formed in the contact surface of the motor rotating shaft with the oil and fat.

Further, a cylindrical bearing holder whose one end is fixed to the frame of the stator and an oil-impregnated bearing which is inserted into the bearing holder by supporting the motor rotating shaft are provided, and the other end of the bearing holder is provided. In addition, a lid is integrally formed to cover the end surface of the oil-impregnated bearing, and the end surface of the oil-impregnated bearing is provided with a recess that is in contact with the lid and the motor rotating shaft and is filled with oil and fat.

[0008]

According to the present invention, the cylindrical bearing holder having one end fixed to the frame of the stator, the oil-impregnated bearing inserted into the bearing holder to support the motor rotating shaft, and the motor rotating shaft are provided. A lid that airtightly penetrates and that hermetically seals the other end opening of the bearing holder, extends the other end of the bearing holder, and bends the end toward the motor rotation shaft side. By forming an oil-filled portion with the lid as the bottom and filling the oil-filled portion with oil, when the lubricating oil oozing out from the oil-impregnated bearing flows out from the joint between the motor rotating shaft and the lid Be blocked.

Further, since the annular recess is formed in the contact surface of the motor rotating shaft with the oil and fat, the oil and fat enters the annular recess.

Further, a cylindrical bearing holder whose one end is fixed to the frame of the stator and an oil-impregnated bearing which is inserted into the bearing holder by supporting the motor rotating shaft are provided, and the other end of the bearing holder is provided. In addition to integrally forming a lid body that covers the end surface of the oil-impregnated bearing into the oil-impregnated bearing, the end surface of the oil-impregnated bearing is abutted with the lid body and the motor rotating shaft, and a recessed portion filled with oil and fat is formed. Lubricating oil that oozes out from the bearing and flows on the motor rotating shaft is blocked by the oil.

[0011]

EXAMPLES Example 1. First Embodiment FIG. 1 is a view showing a first embodiment of the present invention, and 20 is a stator 2 which constitutes an inner ring of an electric motor 21.
Reference numeral 2 denotes a frame, and 23 denotes a bearing holder whose one end 24 is fitted and fixed to the frame. An oil and fat filling portion 27 is formed by bending the motor rotation shaft side to be disposed and having the lid as a bottom portion. Reference numeral 28 denotes an oil-impregnated bearing, which is made of, for example, a sintered alloy, has a rotary shaft hole in the center, and is press-fitted into the bearing holder 23. Numeral 29 designates a motor rotary shaft which is fitted and supported in the rotary shaft hole of the oil-impregnated bearing.
Reference numeral 0 denotes a lid, which is positioned on the stepped portion 26 in the bearing holder 23 and is airtightly fitted so as to be in close contact with the end surface of the oil-impregnated bearing 28, and the motor rotation shaft 29 is airtightly penetrated in the center thereof. The hole is provided. Reference numeral 31 is an oil and fat, which is, for example, a silicon-based hard material and has a grease shape in a normal use range, and is filled in the oil and fat filling portion 27. Reference numeral 32 denotes an annular recess formed in the outer surface of the motor rotating shaft 29 that comes into contact with the oil and fat.
Is filled. 33 is a stator core of the stator 22,
The coil 34 is wound. Reference numeral 35 is a retaining member attached to the protruding end of the motor rotating shaft 29 from the oil-impregnated bearing 28, 36 is a slip washer superposed on the retaining member, and 37 is fixed to the other end of the motor rotating shaft 29. A rotor having a magnet 38, 39 is a sealing plate on the fixed end side of the bearing holder 23, and 40 is a thrust receiving plate abutting against the end face of the motor rotating shaft 29.

In the bearing device for an electric motor constructed as described above, the internal pressure of the oil-impregnated bearing 28 rises as the electric motor 21 is operated to rotate the motor rotating shaft 29.
This internal pressure pushes the internal oil toward the open surface of the oil-impregnated bearing 28. That is, the oil flows to the outer periphery of the oil-impregnated bearing 28 and the sliding surface. In this case, the oil that has exuded from the outer periphery of the lid 30 is covered with the layer formed by the oil and fat 31 and is prevented from flowing out, so that there is no outflow. Further, in the annular recess 32 of the motor rotating shaft 29, the close contact between the oil / fat 31 and the motor rotating shaft 29 is improved, and the sealing effect is improved.

Embodiment 2. In the first embodiment, the other end 25 of the bearing holder 23 is extended and bent to form the oil and fat filling portion 27 with the lid 30. However, as shown in FIG. A lid 50 is formed by bending without extending and covers the end surface of the oil-impregnated bearing 28. Then, a concave portion 52 is formed on the contact surface of the oil-impregnated bearing 28 with the lid 50 and the motor rotating shaft 29, and the concave portion 52 is filled with the oil 31 to obtain the same effect as that of the first embodiment. With
The bearing holder 23 can be downsized, and the electric motor 21 can be made compact.

[0014]

As described above, according to the present invention, a cylindrical bearing holder whose one end is fixed to the frame of the stator, and an oil-impregnated bearing which is fitted and inserted to support the motor rotating shaft in the bearing holder, A lid that airtightly penetrates the motor rotation shaft and that hermetically seals the other end opening of the bearing holder, extends the other end of the bearing holder, and folds the end portion toward the motor rotation shaft side. By bending to form an oil-and-fat filled portion with the lid as the bottom, and the oil-and-fat filled portion was filled with the oil and fat, the internal pressure of the oil-impregnated bearing during operation increased and the impregnated oil outside the bearing holder It is possible to prevent accidents due to lack of lubricating oil over a long period of time by preventing oil and fat from escaping to the oil and fat provided in the oil and fat filling section.

Further, since the annular concave portion is formed in the contact surface of the motor rotating shaft with the oil and fat, the motor rotating shaft and the oil and fat are closely adhered to each other, and the sealing property is improved.

Further, a cylindrical bearing holder whose one end is fixed to the frame of the stator and an oil-impregnated bearing which is inserted into the bearing holder by supporting the motor rotating shaft are provided, and the other end of the bearing holder is provided. In addition to integrally forming a lid body that covers the end surface of the oil-impregnated bearing, and by forming a recessed portion that is in contact with the lid body and the motor rotation shaft and that is filled with oil and fat, is formed on the end surface of the oil-impregnated bearing. It is possible to reduce the manufacturing cost by not providing a lid with parts and prevent the impregnated oil from leaking out of the bearing holder by the oil and fat provided in the recess, preventing accidents due to lack of lubricating oil for a long period of time. You can

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a first embodiment of the present invention.

FIG. 2 is a vertical sectional view showing a second embodiment of the present invention.

FIG. 3 is a vertical sectional view showing a conventional bearing device for an electric motor.

[Explanation of symbols]

 20 frame 22 stator 23 bearing holder 24 one end 25 the other end 27 oil and fat filling portion 28 oil impregnated bearing 29 motor rotating shaft 30 lid 31 oil and grease 32 annular recess 50 lid 52 recess

Claims (3)

[Claims] 1. A cylindrical bearing holder, one end of which is fixed to a frame of a stator, an oil-impregnated bearing which is inserted into the bearing holder so as to support a motor rotating shaft, and the motor rotating shaft is penetrated airtightly. And a lid that hermetically seals the other end opening of the bearing holder, the other end of the bearing holder is extended, and the end is bent toward the motor rotation shaft side to close the lid. A bearing device for an electric motor, characterized in that an oil-and-fat-filled portion serving as a bottom portion is formed, and the oil-and-fat-filled portion is filled with oil and fat. 2. A bearing device for an electric motor according to claim 1, wherein an annular recess is formed in a contact surface of the motor rotating shaft with the oil and fat. 3. A cylindrical bearing holder, one end of which is fixed to a frame of a stator, and an oil-impregnated bearing, which is inserted into the bearing holder so as to support a motor rotation shaft, and the other end of the bearing holder. In addition to integrally forming a lid body that covers the end surface of the oil-impregnated bearing, the end surface of the oil-impregnated bearing is abutted with the lid body and the motor rotation shaft, and a recessed portion filled with oil and fat is formed. Motor bearing device.