JPS6289449A - Bearing device of rotary electric machine - Google Patents

Abstract

PURPOSE:To heighten the external pressure to the lubricating room so as to prevent the leakage of lubricant and enhance the water-proof effect by providing an annular air room to slue around the shaft on the outside of the lubricating room located on the side of a bearing and by supplying a part of cooling wind of the main motor. CONSTITUTION:A lubricating room 11 is provided to fill the lubricant on both sides of a rolling bearing 4 axially supporting a rotor shaft 6, while annular air rooms 14 and 15 are provided which slue around the rotor shaft 6 adjacent to this lubricating room 11. Of these air rooms the air room 15 on the in-unit side communicates the in-unit space 13 and the lubricating room 11 through the labyrinth, while the air room 14 communicates the out-unit space and the lubricating room 11 through the labyrinth. a part of the in-unit cooling air is supplied to these air rooms 14 and 15 through a scavenging port 19 and a communicating hole 20 and the air is exhausted through a communicating hole 21 and an exhaust port 22.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a bearing device for a rotating electrical machine, and more particularly to a bearing device for a rotating electrical machine used as a main electric motor for a vehicle.

[Technical background of the invention]

Grease lubrication is preferred over oil lubrication in bearing devices for rotating electric machines used as main electric motors for vehicles because it is relatively easy to prevent oil leaks and the structure of the bearing device is simple. .

Incidentally, in recent years, induction traction motors controlled by VVVF inverters have been put into practical use, and it has become possible to make the traction motors smaller and lighter and increase their capacity in order to increase the rotation speed of the traction motors. When the speed of the main motor was increased, bearing lubrication became a problem, so it was necessary to switch from grease lubrication to oil lubrication.
What is disclosed in No. 0225 and the like is known.

To explain such a conventional bearing device based on FIG. 7, bearing boxes 101 and 102 are provided on both sides of a stator frame 100, and rolling bearings 10 are installed in these bearing boxes 101 and 102.
The rotor shaft 105 is supported by these bearings 103, 104, and furthermore, the end face of the bearing 103, 10/I is closed with an end cover 106, 107, and the bearing 103, 1
Lubricating oil chambers 108 and 109 are formed on the sides of 04, and lubricating oil is stored in the lower part of the lubricating oil chambers 108 and 109.

A ventilation fan 110 is attached to the rotor shaft 105, and the rotation of the fan 110 blows the air inside the machine to the exhaust port 1.
11, and outside air is sucked into the machine through a ventilation filter 112 installed at the end of the frame to cool the machine.

The main electric motor is supported on the truck by a fixed arm 113 provided on the frame, and a coupling 114 is attached to one end of the rotor shaft 105 to transmit rotational force to the drive device.

[Problems with back silver technology]

In the conventional oil-lubricated bearing device described above, the rolling elements of the bearings 103 and 104 stir the lubricating oil during high-speed rotation,
The atomized lubricating oil fills the lubricating oil chambers 108 and 109. Here, the interior of the main motor is under negative pressure due to the exhaust action of the general purpose fan 110, so outside air flows into the interior of the machine through the labyrinth seals 115 and 116, which have minute gaps, and the lubricating oil chamber 108 , 109 will also leak into the machine.

Furthermore, due to the high-speed rotation of the bearing 103, the pressure within the lubricating oil chamber 108 locally increases, causing mist of lubricating oil within the lubricating oil chamber 108 to leak out of the machine through the labyrinth seal 115.

In order to prevent the lubricating oil leak mentioned above, it is possible to make the labyrinth seal more complex and increase the ventilation resistance.
In the long term, it is not possible to completely prevent oil leaks, and the overall size of the device increases, making it impossible to use it in areas where space is limited, such as in vehicle traction motors.

Furthermore, if a contact type mechanical seal is used instead of a labyrinth seal, oil leakage can be prevented, but there are problems in its use in high-speed machines because the seal generates heat and wears out.

As mentioned above, in conventional oil-lubricated bearing devices, oil leakage cannot be completely prevented, and as a result, the leaked oil contaminates the inside and outside of the machine, and increases oil consumption. It can be said that it is difficult to adopt this method for products that require no maintenance for a long period of time, such as main electric motors.

Furthermore, by changing from a conventional DC traction motor to an induction traction motor, maintenance of the traction motor becomes almost unnecessary, so it is being considered to significantly extend the decomposition and regression period. In this case, the main motor remains attached to the bogie, but when inspecting the bogie, the entire bogie is sprayed with water and the inspection area is cleaned, so the main iF
IIFM will also be affected. As a result, water enters the bearing through the labyrinth seal, causing deterioration of the lubricating oil. When cleaning the trolley, it is necessary to remove the main motor from the trolley, which is a tedious task.

[Purpose of the invention]

The present invention was devised in view of the above circumstances, and its purpose is to eliminate lubricating oil leakage and achieve long-term maintenance-free operation, and at the same time, to prevent water from entering the lubricating oil chamber when water is poured for vehicle washing. It is an object of the present invention to provide a bearing device for a rotating electric machine that does not require any trouble.

[Summary of the Invention] In order to achieve the above object, the present invention provides a lubricant chamber on the side of a bearing that supports the rotor shaft, and an annular air chamber surrounding the rotor shaft outside the lubricant chamber. A part of the cooling air for the main motor is supplied to this air chamber through the air supply hole, and the air in the air chamber is discharged to the outside or inside of the machine through the exhaust hole. be. According to the invention,
While the traction motor is operating, a portion of the cooling air from the traction motor enters the air chamber and pressurizes the air chamber, preventing atomized lubricant from leaking from the lubricant chamber of the cooler 1 receiver. Also, water that enters through the labyrinth seal during truck cleaning is discharged to the outside of the machine through the air chamber.

[Embodiments of the invention] Embodiments of the present invention will be described below based on the accompanying drawings.

FIG. 1 is a longitudinal sectional view of the bearing device according to the first embodiment, and FIG. 2 is a view taken in the direction of the ■ arrow in FIG.
A bearing box 2 is attached to the bearing box 2, and a rotor shaft 6 is rotatably supported by a rolling bearing 1 housed in the bearing box 2, and the outer surface of the bearing 4 is closed with an end cover 2a.

Furthermore, lubricating oil chambers 11.11 are formed on both sides of the bearing 4, and air chambers 14.15 are formed outside the lubricating oil chambers 11.11.
is formed. And lubricating oil chamber 11 and air chamber 1 = 1-
．． 15 are connected by a labyrinth seal with a minute gap, and the air chambers 14 and 15 are connected to labyrinth seals 2b and 2c, respectively.
It communicates with the outside of the aircraft or the inside space 13.

Further, the air chambers 14, 15 are annular so as to go around the rotor shaft 6, and each air chamber 11, 15 is connected to the communication hole 20 in the -L section.
The upper communication hole 20 has a ventilation hole 19, and the lower communication hole 21 has an exhaust hole 22.
is open, and a guard 23 is provided at the outlet of the air hole 22.

On the other hand, a coupling 7 is attached to the outer shaft end of the rotor shaft 6 and connected to the drive device, and a ventilation fan 8 is fixed to the interior of the machine. A plurality of exhaust ports 9 are formed, a guide 16 is provided in a part of the exhaust port 9 (), and air blow holes 17,
A portion of the cooling air is supplied into the air chambers 14 and 15 through the ventilation passage 18 and one ventilation hole.

In the above, as the rotating electrical machine rotates, the airflow fan 8 discharges air inside the machine from the tillage port 9 to the outside of the machine, but part of the discharged air is passed through the ventilation hole 17, the ventilation passage 18, and the ventilation hole 19 by the guide 16. It flows into the communication hole 20. And the communication hole 20
is the air chamber 14. ．． 15, the exhaust air flows into the air chambers 14 and 15. Air chamber 14. ．． A part of the air that has flowed into the labyrinth seals 2b and 2c leaks into the outside of the machine and the interior space 13, but most of the air is discharged to the outside of the machine from the exhaust hole 22 via the lower communication hole 21.

Note that one feed hole is formed in two places and the exhaust hole 22 is formed in one place, so the labyrinth seal 2I).

Even if there is a slight leak from 2C, a difference in resistance will occur between air supply and exhaust, and the air chambers 14 and 15 will be pressurized above atmospheric pressure. Furthermore, the air chamber 14-. 15 are connected through the communication hole 20, so the rain air chambers 14 and 15 are approximately equal pressure -C
There is. Therefore, during operation, the air inside the lubricating oil chamber 11 is 1/l of the air chamber.

15, and the atomized lubricating oil contained in the air in the lubricating oil chamber 11 will not leak into the air chamber 1/1.15.

Also, during operation, since the internal space 13 is under negative pressure, the air in the air chamber 15 is sucked through the labyrinth seal 2C, but the amount of air sucked is determined by the common resistance of the labyrinth seal 2C. Since the air is large, the amount is extremely small, and since the air chamber 15 is supplied with air from the ventilation hole 19 and the communication hole 20, the pressure in the air chamber 15 will not become negative pressure, and the lubricating oil chamber 11 will not be affected. Air and mist oil contained therein will not leak into the air chamber 15.

On the other hand, as the rotational speed of the rotating electric machine increases, the negative pressure in the machine interior space 13 increases, and the amount of air sucked from the labyrinth seal 2C increases, but at the same time, the amount of air supplied to the air chamber 15 from the ventilation hole 17 also increases. Since the pressure in the air chamber 15 increases, the pressure in the air chamber 15 does not decrease, and there is no problem in preventing leakage from the lubricating oil chamber 11.

In addition, even if the amount of air blown increases significantly as the rotation speed increases, the pressure inside the air chamber 14.15 will not rise more than necessary because it is exhausted outside the 'C machine through the illll air hole. Therefore, a stable oil leak prevention effect is exhibited without causing local oil leakage due to a significant increase in pressure within the lubricating oil chamber 11.

On the other hand, if you spray water from the nozzle to clean the rotary type II (main electric motor) while it is still attached to the trolley, if you do this while the rotary electric machine is rotating at a constant rotation speed, the air chamber 14 Labyrinth seal 2b because .15 is pressurized
, 2c will not allow water to enter. Furthermore, even when the rotating electric machine is not rotated when cleaning the trolley, water that has entered through the labyrinth seals 2b and 2c is discharged to the outside of the machine via the communication hole 21 and exhaust hole 22 that communicate the air chambers 14 and 15.
It does not enter into the lubricating oil chamber 11. In particular, since the guard 23 is provided in the tJl air chamber, water is prevented from flowing directly back into the air chamber 14, 15.

3 to 6 are views showing other embodiments. In the embodiment shown in FIG. 3, the bearing device on the non-drive side is shown, and the bearing box 3 supported on the frame 1 A rotor shaft 6 is supported by a rolling bearing 5 housed in a rotor shaft 6, the end face of the bearing 5 is closed by an end swallow 3a, and lubricating oil chambers 12 are formed on both sides of the bearing 5.

Then, an air chamber 24 is installed adjacent to the lubricating oil chamber 12 on the inside of the machine. This air chamber 24 and the lubricating oil chamber 12 are communicated via a labyrinth seal.
A is communicated with the labyrinth seal 3b.

In addition, a guide 2 is attached to a part of the exhaust port on the outer periphery of the ventilation fan 8.
5 (), and the guide 25 and the air chamber 2/I are connected to the air pipe 26 and air holes 27, 28 provided outside the frame 1.
Furthermore, the lower part of the air chamber 24 and the outside of the machine are communicated by an antagonism chamber 29.

With the above configuration, a part of the exhaust air from the rotating electric machine flows into the air chamber 2/I and pressurizes the inside of the air chamber 24, thereby preventing oil leakage from the lubricating oil chamber 12. .

In addition, even if water injected from the nozzle enters the machine from the general purpose filter 10 and flows into the bearing section through the labyrinth seal 3b during truck cleaning, the air chamber 2/l lower part 1]
It is discharged from the air hole 29 to the outside of the machine and does not enter the lubricating oil chamber 12.

Fig. 4 shows an example in which the main motor is applied to an externally ventilated main motor without a self-ventilating fan, in which a feeder 130 is attached to the frame 1, and cooling air is supplied to the inside of the machine from the vent 31. . And the cooling air that cooled the cabin was tJl wind port 9.
is ejected from the aircraft.

-C1 In this embodiment, a part of the cooling air is sent from the air outlet 31 of the blower lit device 30 to the air chamber 1/1 through the air pipe 32, the air passage 18, the air hole 19, and the communication hole 20. .1
5, and also to the air chambers (not shown) of the bearing section on the non-drive side through the air supply pipe 33, so that each air chamber is pressurized.

Even with the above configuration, the same effects as described above can be achieved.

In the embodiment shown in FIG. 5, the exhaust air from the ventilation passage 18 is supplied to the air chamber 15 through the ventilation hole 19, and the air chamber 15 and the air chamber 14 are provided at different positions on the circumference. They are communicated through a communicating hole 20. Such a structure can be said to be effective when the negative pressure generated inside the machine is large and the amount of air sucked into the machine from the labyrinth seal 2C is large.

In the embodiment shown in FIG. 6, the air chamber 14.1
+jl air chamber 21a that also serves as a drainage hole formed at the bottom of 5
, 21b, and 22 are communicated with the interior space 13 through an opening 22a. Even with this configuration, the same effects as described above can be achieved.

Although the above embodiments have been described as oil-lubricated bearing devices, a grease-lubricated bearing device may also be used.

In other words, according to the present invention, the rain air chamber can be pressurized and the pressure difference in the rain air chamber can be eliminated, so the air circulation inside the lubricating grease filling chamber on the bearing side can be eliminated, and therefore, the dust from the outside can be removed. Intrusion and contamination of the filled grease can be prevented. Furthermore, a grease lubrication method also exhibits the same effect in preventing water intrusion during cleaning.

[Effects of the Invention] As explained above, according to the present invention, a lubricant chamber is provided on the side of a bearing of a rotating electric machine, an air chamber is provided adjacent to this lubricant chamber, and this air chamber is used as a part of a rotating electric machine. By using part of the cooling air to pressurize the bearing, it is possible to prevent the bearing lubricant from leaking, and it also prevents contamination and deterioration, making it possible to replenish and replace lubricant over a long period of time. No other maintenance is required.

Furthermore, even if the rotating electric machine is cleaned while it is attached to the cart, water will not enter, so it is possible to increase the speed of the rotating electric machine and extend the disassembly period.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a bearing device according to the present invention, FIG. 2 is a view taken in the direction of the ■ arrow in FIG. 1, FIGS. 3 to 6 are cross-sectional views of other embodiments, and FIG. FIG. 3 is a cross-sectional view of the bearing device. 1... Frame, 2, 3... Bearing box, 4, 5...
Rolling bearing, 6... Rotor shaft, 11.12... Lubricating oil chamber, 14.15... Air chamber, 17.19... Air supply hole, 20° 21... Communication hole, 22 ...II Chikiana Applicant's Agent Sato - Iroaru / Zutsuri 3 Zuyu 4 Figure

Claims (1)

[Claims] 1. A bearing device in which a rotor shaft is supported by a rolling bearing housed in a bearing box supported by a stator,
A lubricant chamber is provided on both sides of the bearing in the axial direction, and an annular inboard air chamber and an annular outboard air chamber are formed adjacent to these lubricant chambers and orbit around the rotor shaft, and the inboard air chamber is a labyrinth. The air chamber outside the machine communicates with the lubricant room and the space outside the machine through a labyrinth.
These internal and external air chambers communicate with each other through a communication hole, and this communication hole has an air supply hole that introduces a portion of the cooling air of the rotating electric machine, and an exhaust hole that discharges the air inside the air chamber to the outside or inside of the machine. A bearing device for a rotating electrical machine characterized by having an open hole. 2. In a bearing device in which a rotor shaft is supported by a rolling bearing housed in a bearing box supported by a stator,
An inboard lubricant chamber and an outboard lubricant chamber are provided on both sides of the bearing in the axial direction, and an annular air chamber surrounding the rotor shaft is formed adjacent to the inboard lubricant chamber, and this air chamber is a labyrinth. The air chamber is connected to the inside lubricant chamber and the inside space of the machine, and the air chamber also has an air supply hole that introduces a part of the cooling air of the rotating electrical machine and an exhaust hole that exhausts the air in the air chamber to the outside of the machine or the inside space of the machine. A bearing device for a rotating electrical machine, characterized in that each of the bearings has an opening.