KR200239831Y1 - Bearing oil leakage prevention structure of motor - Google Patents

Abstract

The present invention can prevent the bearing oil from leaking inside the blade by mounting a structure between the bearing cover and the bearing that can cause a pressure difference having a direction opposite to the pressure difference caused by the blade mounted on the rotor. The present invention relates to a bearing oil leakage preventing means of an electric motor, which is inserted into a rotating shaft so as to be positioned between a bearing and a bearing cover of an electric motor. Radial length grooves are formed on one inclined surface opposite the cover, and an insertion piece for guiding the rotating shaft is formed through the insertion holes on both sides so that the bearing oil is formed through the gap between the bearing cover and the rotating shaft. There is an effect of preventing leakage to the inside.

Description

Bearing oil leakage prevention structure of motor

The present invention relates to a structure for preventing leakage of bearing oil in an electric motor, and more particularly, a structure capable of inducing a pressure difference having a direction opposite to a pressure difference caused by a blade mounted to a rotor between a bearing cover and a bearing. The present invention relates to a bearing oil leakage preventing structure of an electric motor which can be prevented from leaking bearing oil to the inner side of a blade by attaching to a shaft.

In general, when an induction motor applies current to a primary winding, a voltage is induced in the secondary winding by an electromagnetic induction action, thereby causing a current to flow, thereby rotating the rotor by a rotational force generated by the interaction of alternating magnetic flux and current. In general, the rotational speed is constant enough to be classified as a constant speed motor, and there is almost no speed change except for the pole number conversion. Therefore, the blades of the fan and the rotor are designed for the purpose of cooling only the motor itself. Hereinafter, the general cooling method of the induction motor will be described.

1 is a half sectional view showing the configuration of a general induction motor.

As shown in FIG. 1, a general induction motor includes a rotor core 110 into which a rotating shaft 100 is inserted, a blade 130 mounted on the rotor core 110, and a rotor core 110. A frame that forms a stator core 120 installed at a predetermined interval, a cooling fan 160 inserted into and fixed to one end of the rotating shaft 100, and the stator core 120 and the rotor iron core 110 to form an external shape. And a bearing 140 mounted to the frame 170 to support the rotating shaft 100, and a bearing cover 150 mounted to the frame 170 to embed the bearing 140.

Reference numeral 122 denotes a stator winding, and 180 denotes an end bracket.

When the voltage is supplied to the stator winding 122 of the induction motor having the above configuration, the induced voltage is induced in the rotor by the induction action, the rotor current flows, and is generated by the interaction between the alternating flux and the rotor current. As the rotor rotates by the force, the cooling fan 160 and the blade 130 also rotate.

Therefore, the cooling wind generated by the rotation of the cooling fan 160 cools the frame 170 body along the outer surface of the frame 170, and the cooling wind according to the rotation of the blade 130 is formed in the stator winding 122. By circulating the generated heat inside the rotor → the end bracket 180, the heat generated inside the motor is dissipated to the outside through the envelope of the end bracket 180.

On the other hand, in recent years, due to the development of inverter technology, the electric motor is widely used for general purposes and is used at high speed, and it is a trend that is small and light. Because of this, the cooling method of the rotor by the blade 130 is made as follows.

When the blade 130 rotates at a high speed, the internal pressure of the blade 130 is further reduced than the pressure of the blade 130 and the pressure of the bearing 140, so that the blade 130 inside and the bearing cover 150 inside the blade 130. It caused a pressure difference between them. As a result, the cooling wind generated by the rotation of the blade 130 enters the inner side of the blade 130 through the inner side surface of the end bracket 180, and the cooling wind is caused by the centrifugal force of the rotating blade 130. By hitting the stator winding 122, the heat of the stator winding 122 is taken away.

However, after the bearing oil in the bearing 140 is sucked into the blade 130 through the gap between the bearing cover 150 and the rotating shaft 100 by the pressure difference generated by the rotation of the blade 130, the blade The centrifugal force of 130 impinges on the stator core 120 and is attached to the stator winding 122. Therefore, the stator windings are burned due to the deterioration of the stator winding 122, the bearing oil of the bearing 140 gradually leaks, and the bearing 1420 is finally fixed, thereby causing the motor to burn out.

The present invention has been made in view of the above problems, and its purpose is to generate a pressure difference in the opposite direction so as to offset the pressure difference caused by the rotation of the blade inside the bearing cover, so that the bearing oil is It is to provide a bearing oil leakage prevention structure of the motor that is not leaked to the outside.

1 is a cross-sectional view showing the configuration of a general induction motor

2 is a perspective view showing a structure for preventing oil leakage of a bearing of the present invention

Figure 3 is a partial cross-sectional view showing a state in which the bearing oil leakage prevention structure of the present invention is mounted on the motor

Explanation of symbols on the main parts of the drawings

1: Bearing oil leakage prevention structure 10: Disc body

12: insertion 2 part 14: length groove

20: insertion hole 100: rotation axis

110: rotor core 120: stator core

130: blade 140: bearing

150: bearing cover 160: cooling fan

170: frame

In order to achieve the above object, the bearing oil leakage prevention structure of the motor of the present invention is inserted into the rotating shaft so as to be located between the bearing and the bearing cover of the motor, and an insertion hole is formed in the center and inclined in both directions from the outer circumference. It is a disk having a radial length groove is formed on one inclined surface facing the bearing cover, the insertion piece for guiding the rotation axis along the periphery of the insertion hole on both sides protrudes.

Therefore, in the bearing oil leakage preventing structure of the motor of the present invention, the bearing oil leakage preventing structure is inserted into the rotating shaft so as to be located between the bearing cover and the bearing so as to offset the pressure difference generated by the rotation of the blade during the high speed rotation. By creating a difference, there is a break that prevents the bearing oil from leaking to the inside of the blade through the gap between the bearing cover and the rotating shaft.

EXAMPLE

Hereinafter, the bearing oil leakage prevention structure of the induction motor of the present invention will be described in detail.

Figure 2 is a perspective view showing a bearing oil leakage prevention structure of the present invention-motor, Figure 3 is a partial cross-sectional view showing a state in which the bearing oil leakage prevention structure of the present invention is mounted to the motor.

In the drawings, the same reference numerals and the same reference numerals are used for the same components, and the detailed description thereof will be omitted in the description of the present invention in order to avoid the confusing description.

In the drawings, reference numeral 1 denotes a bearing oil leakage preventing structure, 10 a disc body, 12 an insertion piece, 14 a length groove, 20 an insertion hole, 122 a stator winding, 130 a blade, 140 a bearing, 150 a bearing cover, 1 Denotes the clearance between the bearing cover and the bearing.

As shown in FIG. 2, the bearing oil leakage preventing structure 1 of the present invention is a disk 10 having an insertion hole 20 formed in the center thereof and both surfaces of which are inclined in the inner circumferential direction from the outer circumference thereof, and inserted into one inclined surface. The length groove 14 is radially formed outward from the center of the hole 20 to cause a pressure difference between the inner circumference and the outer circumference during rotation, and to guide the rotating shaft 100 along the circumference of the insertion hole 20 on both sides. The insertion piece 12 protrudes.

Here, the bearing oil leakage preventing structure 1 of the present invention is inserted and fixed to the rotating shaft 100 so as to be located between the bearing cover 150 and the bearing 140 of the electric motor, as shown in FIG. At this time, the length groove 14 should be opposed to the inner bearing cover 150 of the motor.

It describes the operation and effect of the present invention in this configuration.

First, as the blade 130 rotates to prevent overheating of the stator winding 122, a pressure difference is caused inside the blade 130 and inside the bearing cover 150, and the bearing oil causes the bearing ( 140 is leaked out of the gap (1) between the bearing cover 150 and the rotating shaft 100 while flowing through the inner surface of the bearing cover 150.

At this time, the bearing oil leakage preventing structure 1 that rotates at a high speed causes a pressure difference in a direction opposite to the pressure difference caused by the blade 130 to the gap 1 between the bearing cover 150 and the rotating shaft 100. The oil leaked bearing oil flows to the outer periphery of the bearing 140 on the inclined surface of the disc 10.

That is, when the bearing oil leakage preventing structure 1 inserted in the rotating shaft 100 rotates at a high speed, the pressure in the shaft inner diameter portion is reduced by the longitudinal groove 14 formed radially around the shaft center. Accordingly, the bearing oil having a specific velocity flowing down the inner surface of the bearing cover 150 flows to the outer diameter of the bearing 140 on the inclined surface of the disc 10. In addition, the bearing oil flowing into the outer diameter of the bearing 140 rides on the inner surface of the bearing cover 150 due to the pressure difference caused by the blade 130, and thus the clearance 1 between the bearing cover 150 and the rotating shaft 100. ), The bearing oil is circulated to the outer circumferential surface of the bearing 140 → the inner surface of the bearing cover 150 → the inclined surface of the disk body 10 → the outer circumferential surface of the bearing 140, and the bearing cover 150 and the rotating shaft 100. It does not leak into the gap 1 between them.

On the other hand, conventional structures having the same action as the above-described bearing oil leakage preventing structure 1 include a radial fan, an impeller, etc., and instead of the bearing oil leakage preventing structure 1 of the present invention, Of course, the radial fan or impeller can be used.

According to the bearing oil leakage preventing structure of the electric motor of the present invention as described above, the bearing oil leakage preventing structure is inserted into the rotating shaft so as to be located between the bearing cover and the bearing to compensate for the pressure difference generated by the rotation of the blade during the high speed rotation. By generating a possible pressure difference, the bearing oil is prevented from leaking to the inner side of the blade through the gap between the bearing cover and the rotating shaft.

Claims (1)

Is inserted into the rotating shaft so as to be located between the bearing and the bearing cover of the motor, the disk is formed in the center and has a double-sided inclined in the inner circumferential direction from the outer circumference and the radial groove on the inclined surface facing the bearing cover This is formed, the bearing oil leakage prevention structure of the electric motor, characterized in that the insertion piece for guiding the rotating shaft along the periphery of the insertion hole on both sides.