JP3360355B2 - Bearing device for rotating electric machine - Google Patents

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 a rotating electric machine used for a nuclear power plant or a thermal power plant.

[0002]

2. Description of the Related Art Rotary electric machines for pumps and fans for nuclear power plants, thermal power plants, and the like use lubricating grease for bearings. Japanese Patent Application Laid-Open No. Sho 62-144545 discloses a known example of this bearing device. This will be described with reference to FIG. In FIG. 4, the bearing 16 is fitted and held from one end side to a bearing bracket 18 rotatably supporting the rotor shaft 17 via the bearing 16 and an inner peripheral portion of a cylindrical bearing housing 19 at the center thereof. A cover 20 surrounding the end surface of the bearing 16 is attached to one end surface of the bearing housing 19. The cover 2 is mounted on the bearing housing 19 from the other end face.
A grease introduction passage 21 is provided in the axial direction that reaches the inner surface of the bearing 16, and the grease is sent to the inner surface of the bearing 16 through the introduction passage 21. An oil thrower 22 on a disk is installed adjacent to the outer end surface of the bearing 16, and a grease of waste grease lubricating the bearing 16 is radially opposed to the oil thrower 22 in the bearing housing 19. The discharge path 23 is shown in FIG.
As shown in FIG. An annular groove 24 communicating with the grease discharge passage 23 is provided on the outer periphery of the bearing housing 19, and the outer surface of the groove 24 is closed by a detachable annular lid 25. The waste grease is pushed out by the centrifugal action accompanying the rotation of the oil thrower 22 and is stored in the annular groove 24. The waste grease accumulated in the groove 24 can be removed by removing the lid 25 and using a scraper or the like.

[0003]

In the above-described conventional bearing device, the flow of air generated by the oil thrower 22 does not enter the grease discharge passage 23 which is tightly closed. Get out of the gap 20. At this time, the base oil of the grease is drawn together with the outflow of air, and leaks out of the cover 20. As a result, there is a problem in that it adheres to and contaminates external peripheral devices.

[0004] It is an object of the present invention to provide a highly reliable bearing device which prevents pollution of the surrounding environment by preventing grease from leaking out of base oil.

[0005]

In order to solve the above-mentioned problems, a grease discharge pipe is provided with a hole for venting air, and a gap between the oil thrower and the cover has a labyrinth structure.

[0006]

According to the above structure, the flow of air generated by the oil thrower is directed to the grease discharge pipe due to an increase in air resistance due to the labyrinth structure of the cover and the effect of the air vent provided in the grease discharge pipe. . The grease base oil discharged from the inside of the bearing by the flow of the air is stored in the grease discharge pipe without leaking to the outside of the cover, and the surrounding environmental pollution can be suppressed.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings of the embodiments.

FIG. 3 shows the structure of the electric motor.
, A rotor 13 fitted to the rotor shaft, a bearing 2 for supporting the rotor shaft 1, and bearing covers 3A, 3B for accommodating the same.
A cover 6 surrounding the end face of the bearing 2 and having a labyrinth structure with a gap between the oil thrower 5 and the rotor 13;
, A cylindrical stator 14 having a certain clearance in the circumferential direction, and bearing covers 3A, 3B holding the outer peripheral surface of the bearing 2.
, And a stator frame 15 for fixing the stator 14 and the bearing bracket 4. FIG. 1 is a diagram showing the bearing device of FIG. 3 in detail. In this figure, the rotor shaft 1 is located above the bearing cover 3A.
A grease extraction pipe 7 is provided in the vertical direction, and a grease nipple 8 is provided at the tip. Bearing cover 3
A, the bearing bracket 4 is provided with grease introduction paths 9A and 9B for allowing grease to reach the inside of the bearing cover 3B. A grease discharge pipe 10 penetrating through the bearing cover 3A in a direction perpendicular to the rotor shaft 1 is provided below the bearing cover 3A. As shown in FIG. A hole 11 for venting air is provided above the center of the portion, and a detachable lid 12 is provided at an end of the hole 11 so that waste grease and base oil do not leak. When new grease is supplied from the nipple 8 with a grease gun, new grease can be sent into the bearing through the grease extraction pipe 7. When new grease is pushed into the bearing, waste grease that has been lubricated and base oil that has oozed out of the grease due to heat generated inside the bearing are greased by centrifugal action due to rotation of an oil thrower 5 installed adjacent to the bearing 2. Flyed to the discharge pipe. At the same time, the flow of air generated by the rotation of the oil thrower 5 increases the air resistance due to the labyrinth structure at the end of the cover 6 and provides the grease discharge pipe 10 with a hole 11 for venting the grease. The base oil drawn toward the discharge pipe 10 accumulates in the grease discharge pipe 10. The waste grease and the base oil accumulated in the grease discharge pipe 10 are removed from the grease discharge pipe 10 by appropriately removing the lid 12, and the lubricating grease of the bearing 2 can be replaced with a new one.

According to the embodiment, since the tip of the cover 6 has a labyrinth structure and the hole 11 is provided in the grease discharge pipe 10, the flow of the air generated by the oil thrower 5 enters the grease discharge pipe 10, and the grease discharge pipe 10 has the same structure as the conventional one. It is possible to prevent the surrounding environment from returning without leaking from the gap between the cover 6 and the oil thrower 5.

[0010]

According to the present invention, a hole for venting air is provided in the grease discharge pipe, and a labyrinth structure is provided between the oil thrower and the cover. It is difficult to flow outside through the gap between the oil thrower and the oil thrower, and passes through the hole for venting the grease discharge pipe. Therefore, the base oil drawn by the flow of air also accumulates in the grease discharge pipe, so that the outflow of the base oil to the outside is reduced,
Reduce surrounding environmental pollution.

[Brief description of the drawings]

FIG. 1 is a sectional view of a bearing device according to the present invention.

FIG. 2 is a side view of a grease discharge pipe.

FIG. 3 is a sectional view of an electric motor having the bearing device of the present invention.

FIG. 4 is a sectional view of a conventional bearing device.

FIG. 5 is a sectional view taken along the line II of FIG. 4;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rotor shaft, 2 ... Bearing, 3A, 3B ... Bearing cover, 4
... bearing bracket, 5 ... oil thrower, 6 ... cover,
7 ... Grease extraction pipe, 10 ... Grease discharge pipe, 11 ...
Hole.

Continuation of the front page (56) References JP-A-53-141853 (JP, A) JP-A 62-70651 (JP, U) JP-A 62-200893 (JP, U) JP-A 63-51554 (JP) , U) Japanese Utility Model Showa 55-29709 (JP, U) Japanese Utility Model Showa 54-115430 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02K 5/173 F16C 33/66 H02K 5/10-5/16

Claims (1)

(57) [Claims] A bearing for supporting a rotor shaft of a rotating electric machine, and the shaft
A bearing cover for accommodating the receiving a bearing bracket wherein the bearing cover is provided which holds the outer peripheral surface of the bearing, is provided in the bearing cover, the grease tube for introducing grease, the bearing cover provided,
In the bearing device for a rotary electric machine and a grease discharge pipe Therefore it is accumulated in the centrifugal force by rotating the waste grease the bearing has finished lubrication oil thrown word provided on the rotor shaft, the grease discharge pipe The grease injection pipe is provided below the oil thrower , and the grease injection pipe is disposed in the axial direction of the bearing.
Meanwhile grease is introduced to the side, while the oil thrown ring together is provided on the other side of the bearing, the other axial side of the oil thrown Wa cover for closing the bearing cover provided, the cover the tip portion of the labyrinth structure, further the oil thrown ring comprises a portion extending in the axial direction other side in contact with the rotor shaft, a bearing other of the oil thrown Wa labyrinth structure of the cover distal The part extended to the side is arranged to be closely opposed in the radial direction ,
And, a bearing device for a rotary electric machine, wherein a hole for venting air generated by rotation of the oil thrown word above the center of the horizontal portion of the grease discharge pipe is provided.