JPH0231582B2 - KAITENDENKI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Field of Application) The present invention relates to a rotating electrical machine, and particularly to a cooling structure for a bearing of a rotating electrical machine.

(Conventional technology) For example, a vehicle motor generator (hereinafter referred to as MG).
As shown in FIG. 1, the bearing portion supports a bearing 9 by a bracket 7 supported by a frame 6, and a rotor shaft 8 is supported by this bearing 9. Bearing 9
An end cover 10 is attached to the end surface of the bearing 9.
Spaces 12 and 13 are formed on both sides of the shaft, and lubricating grease is sealed in these spaces 12 and 13. A cooling fan 14 is attached to the rotor shaft 8, and as the MG rotates, air inside the machine is discharged to the outside of the machine through an exhaust port 3 provided in a bracket 7, thereby cooling the MG through ventilation.

The temperature of the bearing 9 rises as it rotates, but in addition to the rise in its own temperature, the temperature of the bracket 7 rises due to the rise in the temperature of the cooling air inside the MG, which further increases the temperature rise of the bearing. In recent years, in order to reduce maintenance and inspection of vehicle MGs, it has become an issue to extend the period for disassembling bearings and renewing grease. A major cause of decreasing the service life of bearing lubricating grease is temperature rise. When the temperature of the bearing 9 increases, the base oil in the grease separates more and the oil disappears more quickly. The rate of chemical deterioration of the grease also increases as the temperature increases. Therefore, if the temperature rise is large, the grease needs to be replaced earlier, making it difficult to save labor in maintenance. In addition, recently we have improved the temperature rise limit by using heat-resistant insulators,
There is a trend toward increasing the capacity of MGs or making them smaller and lighter. In this case, the temperature rise of the exhaust air (cooling air) gradually increases, and the temperature effect on the bearing also increases, resulting in an even faster return to replacement of the bearing lubricating grease.

On the other hand, various studies have been made to suppress the rise in temperature of this bearing, one of which is a structure shown in FIG. In the one shown in FIG. 2, a plurality of outside air introduction holes 16 are provided in the bracket 7 and the end cover 10 at the outer periphery of the bearing 9. Outside air flows into the space 15 inside the machine through this outside air introduction hole 16, and is exhausted together when the air inside the MG is exhausted. By flowing outside air through the introduction hole 16 and the space 15, the bearing 9 is cooled, and the bracket 7 is also cooled, thereby reducing the influence on the bearing, thereby reducing the temperature rise of the bearing.

(Problems to be Solved by the Invention) However, this structure has the following problems. Since the MG for vehicles is hung and installed outside under the floor of the car body, as shown in Figure 3, the MG cooling air is
Outside air is taken in through a ventilation filter 2 installed at the outside air intake of the MG 1, and dust, winter rain, rainwater, etc. contained in the outside air are removed. Furthermore, other equipment such as a resistor 5 is connected to the exhaust side of the MG 1, and ventilation cooling is performed using the exhaust air.

In this case, if the outside air introduction hole 16 shown in FIG. 2 is provided, dust, water, and snow will be mixed into the outside air flowing in through the outside air introduction hole 16, and this will enter the machine and the labyrinth part 17 of the lubricating grease filling part. This is a practical problem because it enters into the bearing and causes contamination and deterioration of the lubricating grease, and also flows into other equipment 5 along with the exhaust air through the space 15, contaminating the inside of this equipment. Ta.

The present invention is intended to solve the above-mentioned problems, and an object of the present invention is to provide a rotating electric machine that can prevent internal contamination and cool bearings.

[Structure of the Invention] (Means for Solving the Problem) In order to achieve the above object, a first invention provides a rotor shaft, a bearing that supports the rotor shaft, and a bearing body that supports the bearing. a cooling fan located on the inboard side of the bearing and attached to the rotor shaft; and an end cover located on the outboard side of the bearing and attached to the outside of the bearing body of the bracket. In an electric machine, a cover is attached to the inside of the bearing body of the bracket and forms a first annular space between the cover and the bearing body, and a cover is formed at a lower part of the bearing body of the bracket and communicates with the first annular space. a ventilation hole formed in the lower part of the end cover that communicates with the ventilation hole; a cylindrical partition plate that together forms a second annular space that is a sealed space; fins provided on the back surface of the cooling fan; an exhaust port formed in a lower part of the second annular space; The cover is characterized by comprising a vent provided in an upper part of the cover and communicating the first annular space and the second annular space.

Furthermore, a second invention includes a bracket having a rotor shaft, a bearing for supporting the rotor shaft, a bearing body for supporting the bearing, and a bracket located on the inside of the machine from the bearing and attached to the rotor shaft. In a rotating electric machine having a cooling fan and an end cover located outside the machine of the bearing and attached to the outside of the bearing body of the bracket, a first annular space formed in the end cover, and a first annular space formed in the end cover; an outside air intake port formed in the lower part and communicating with the first annular space; and a second air intake port protruding from the inside of the bracket near the outer peripheral part of the cooling fan and forming a sealed space together with the back surface of the cooling fan and the bracket. a cylindrical partition plate forming an annular space, fins provided on the back surface of the cooling fan, an exhaust port formed in the lower part of the second annular space, and a bearing body of the bracket. The first annular space and the second annular space
It is characterized by having a plurality of ventilation holes communicating with the annular space.

(Function) According to the first invention configured as described above, the air in the second annular space is discharged to the outside of the machine from the exhaust port due to the rotation of the fins. Therefore, outside air is sucked in through the outside air intake port, flows into the first annular space through the ventilation hole, and cools the bearing body through ventilation. Furthermore, the outside air is passed from this first annular space to the second annular space through the vent.
flows into the annular space of Furthermore, the partition plate prevents the high-temperature exhaust air discharged by the cooling fan from flowing into the second annular space, thereby suppressing a rise in the temperature of the bracket.

Furthermore, according to the second invention, outside air is sucked in through the outside air intake port, flows into the second annular space through the first annular space and the ventilation hole, and performs ventilation cooling of the bearing body. The rest is the same as the first invention.

(Example) An example of the present invention will be described below with reference to FIGS. 4 and 5. 6 is an MG frame, a bracket 7A supported by this MG frame 6 supports a bearing 9, and the rotor shaft 8 is supported by this bearing 9. A cooling fan 21 is attached to the rotor shaft 8 on the inside of the bearing 9.

Further, the bracket 7A has a bearing body 7B formed at the mounting portion of the bearing 9, and a side portion 7C formed on the inboard side of this bearing body 7B. An end cover 20 is provided on the outside of the bearing body 7B on the outside of the bearing 9, and a cover 19 is attached on the inside of the bearing body 7B.
A first annular space 25 is formed by this cover 19 and the side portion C of the bearing body 7B. An outside air intake port 23 that opens downward is provided in the lower part of the end cover 20,
Further, one or more ventilation holes 24 communicating with the outside air intake port 23 are provided in the lower part of the bearing body 7B.
Further, one or more ventilation holes 26 are provided in the upper part of the cover 19.

A plurality of fins 22 are provided on the back surface of the cooling fan 21 on the bearing side. Further, a cylindrical partition plate 29 protruding close to the outer circumference of the cooling fan 21 is provided on the inside of the bracket 7A, and this partition plate 29,
A second annular space 27, which is a closed space, is defined by the back surface of the cooling fan 21, the bracket 7A, and the cover 19. The second annular space 27 and the first annular space 5 communicate with each other through the vent 26 described above. Furthermore, an exhaust port 28 communicating with the outside is formed in the lower part of the second annular space 27.

Next, the effect will be explained. The second annular space 2 is opened by rotating the fins 22 provided on the back side of the cooling fan 21.
The air inside 7 is discharged to the outside of the machine from a lower discharge port 28. For this reason, outside air is sucked in through the outside air intake port 23 at the bottom of the end cover 20, passes through the ventilation hole 24,
It flows into the lower part of the first annular space 25. Furthermore, the first
The cooled outside air rising through the annular space 25 is passed through the cover 19.
The air flows into the second annular space 27 through the vent hole 26 provided in the upper part of the air.

In this way, the outside air is circulated around the side portion 7C of the bearing body 7B to cool it, so that a rise in temperature of the bearing 9 can be suppressed. The high-temperature exhaust air from the cooling fan 21 of the MG is discharged after circulating inside the exhaust wind tunnel 30, but because it does not flow into the second annular space 27 due to the partition 29, the temperature rise in the bracket 7A is also suppressed, and the bearing 9 can reduce the impact on

Further, since the outside air intake port 23 is provided at the lower part of the end cover 20 and opens downward, it is difficult for snow, water, etc. to enter. Dust mixed in the outside air taken in is also sealed in the second annular space 27 by the partition 29, so it does not enter the wind tunnel 30, and it can also mix into the MG exhaust air and contaminate other equipment. do not have.

Next, another embodiment of the present invention will be described with reference to FIG. A first annular space 31 is formed in the end cover 20A, and this first annular space 31 communicates with the outside air intake port 23. Further, a plurality of ventilation holes 24A are formed on the circumference of the bearing body 7B, and the ventilation holes 24A are formed on the circumference of the bearing body 7B.
The first annular space 31 and the second annular space 2 via
7 is connected.

In this embodiment, the outside air is
The first annular space 31 and the ventilation hole 24
A, further passes through the second annular space 27 and is discharged from the discharge port 28 to the outside of the machine.

As a result, the heat generated in the outer circumferential portion of the bearing 9 is discharged to the outside of the machine by the cooling air, so that temperature rise can be effectively suppressed.

[Effects of the Invention] As explained above, according to the present invention, the bearing part is cooled by forcibly circulating outside air around the bearing part, suppressing heat generation, and preventing thermal deterioration of the lubricating grease of the bearing. It is possible to prevent this and extend the life of the lubricating grease.

Therefore, extremely beneficial effects such as not only improving the thermal stability performance of the bearing but also making it possible to extend the maintenance and inspection period are achieved.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing a conventional MG cooling fan side bearing structure, Fig. 2 is a partial sectional view showing a conventional MG bearing cooling structure, Fig. 3 is a plan view showing how the MG is installed under the vehicle floor, and Fig. 4 is a partial sectional view showing the conventional MG cooling fan side bearing structure. 5 is a side view of FIG. 4, and FIG. 6 is a cross-sectional view of another embodiment of the invention. 7A, 7D... Bracket, 7B... Bearing body,
8... Rotor shaft, 9... Bearing, 19... Cover,
20... End cover, 21... Cooling fan, 22...
...Cooling fin, 23...Outside air intake, 24, 24
A...Vent hole, 25, 31...First annular space,
26...Vent, 27...Second annular space, 28
...exhaust port, 29...partition plate.

Claims (1)

[Scope of Claims] 1. A rotor shaft, a bearing for supporting the rotor shaft, a bracket having a bearing body for supporting the bearing, and a bracket located on the inside of the machine from the bearing and attached to the rotor shaft. In a rotating electric machine having a cooling fan and an end cover located on the outside of the bearing and attached to the outside of the bearing body of the bracket, an end cover is installed on the inside of the bearing body of the bracket and between the end cover and the bearing body. a cover forming a first annular space; a ventilation hole formed in the lower part of the bearing body of the bracket and communicating with the first annular space; and an outside air hole formed in the lower part of the end cover and communicating with the ventilation hole. an intake port; a cylindrical partition plate that protrudes from the inside of the bracket near the outer periphery of the cooling fan and forms a second annular space that is a sealed space together with the back surface of the cooling fan and the bracket; fins provided on the back of the fan, an exhaust port formed in the lower part of the second annular space, and the first air outlet provided in the upper part of the cover.
A rotating electrical machine, comprising: a vent that communicates an annular space with a second annular space. 2. A rotor shaft, a bearing for supporting the rotor shaft, a bracket having a bearing body for supporting the bearing, a cooling fan located on the inside of the machine from the bearing and attached to the rotor shaft, and the bearing. an end cover located on the outside of the machine and attached to the outside of the bearing body of the bracket; a first annular space formed in the end cover; an outside air intake that communicates with the first annular space, and a second annular space that protrudes from the inside of the bracket near the outer circumference of the cooling fan and is a sealed space together with the back surface of the cooling fan and the bracket. A cylindrical partition plate, fins provided on the back surface of the cooling fan, an exhaust port formed in the lower part of the second annular space, and a fin formed in the bearing body of the bracket and the first annular space. A rotating electrical machine, comprising: a plurality of ventilation holes communicating between the space and the second annular space.