JPS61254041A - Bearing device for rotary electric machine - Google Patents

Abstract

PURPOSE:To prevent lubricant from leaking, a machine from being deteriorated due to the mixture of foreign matters, and a roller bearing from being damaged, by arranging ring-shaped elastic rubber units almost to come in contact with a rotary shaft, between the inner diameter side of lubricant filler chambers confronting the side face of the roller bearing and the rotary shaft. CONSTITUTION:Oil seals 100 are fixed on the inner diameter side of lubricant filler chambers 60 and 70 arranged on bearing covers 40 and 50 placed on the both sides of a roller bearing covers 40 and 50 placed on the both sides of a roller bearing 2. Generally, metal rings 100E are arranged on the outer diameter side. Open air is absorbed into a machine through an air chamber 8 via an air passage 10 through an air chamber 9. The main units 100D of the oil seals 100 are generally made of elastic rubber, and the material is determined subject to the adequate use. On the inner diameter side, namely, on the surface confronting a rotary shaft 1, lips 100A and 100B are arranged on the both sides, and the sections are arranged to come in contact with the rotary shaft 1. Accordingly, lubricant and base oil can be prevented from being leaked by the one side lip, and foreign matters included in open air can be prevented from being infiltrated by the counter side lip.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a bearing device for a rotating electrical machine, and particularly to a rotating electrical machine suitable for use in an atmosphere with a lot of rainwater or dust, such as a rotating electrical machine for a vehicle. Related to bearing devices for electrical machinery.

[Background of the invention]

In recent years, there has been a demand for long-term maintenance-free equipment in various fields, and in particular, in bearing equipment with rolling bearings, lubricant replacement intervals have been extended to extend the life of bearing equipment. One of the major challenges is to eliminate maintenance during the period. In particular, induction motors do not have commutators, brushes, or brush holders, so the only part that requires maintenance is the bearing device. The need is great. In particular, in recent years, induction motors have come to be used in rotating electric machines for vehicles, and the demand for long-term maintenance-free operation is increasing in this field as well.

By the way, in bearing devices for rotating electric machines for vehicles and bearing devices for rotating electric machines used outdoors in dusty atmospheres, water and dust can enter the bearing device and deteriorate the lubricant, causing damage to the rolling bearings. To prevent damage to the bearings, the lubricant must be replaced and the bearing assembly must be disassembled and cleaned frequently.

Therefore, the bearing devices shown in Figures 4 and 5 have been put into practical use with the purpose of protecting the bearing devices from water and dust, extending the period for lubricant replacement and disassembly of the bearing devices, and eliminating the need for long-term maintenance. has been made into

In other words, this bearing device prevents water and dust from entering the lubricant filling chamber and the rolling bearing due to air pressure fluctuations occurring around the bearing device. The dynamic bearing part is constructed so that the pressure is always equalized regardless of fluctuations in air pressure. This bearing device will be specifically explained.

In FIG. 4, a rolling bearing 2 supporting a horizontally extended rotating shaft 1 is supported at its outer diameter by a bearing box 3.
Both axial sides of the rolling bearing 2 are covered with an inner bearing cover 4 and an outer bearing cover 5, respectively. Lubricant filling chambers 6 and 7 are formed in the inner bearing cover 4 and the outer bearing cover 5 at positions facing the side surfaces of the rolling bearing 2, respectively. Grease is included.

Furthermore, air chambers 8 and 9 are provided adjacent to each other on the outside of the lubricant filling chambers 6 and 7, that is, on the reverse motion bearing side. Each of these air chambers 8 and 9 is formed all around the edge of a minute gap formed by the partition walls 6w and 7w that constitute the lubricant filling chamber 6.7 and the rotating shaft 1 that is a rotating body. ing.

Furthermore, each air chamber 8 located on both sides of these rolling bearings 20
, and 9 are communicated with each other by an air flow path 10. Note that the air chambers 8 and 9 do not necessarily need to communicate with each other, and the other end of the air flow path connected to the air chamber 8 is open to the outside air from the external bearing cover 5, and the air flow path connected to the air chamber 9 is opened to the outside air. The other end of the flow path may be opened into the rotating electric machine through the internal bearing cover 4.

In the bearing device configured as described above, when the inside of the rotating electric machine becomes negative pressure during operation, outside air enters through the gap between the rotating shaft l and the external bearing cover 5 as shown by the arrow, but the air chamber After entering 9, the air flow path l with low flow resistance
0, enters the air chamber 8 located on the opposite side, and enters the rotating electrical machine from the core through the gap between the rotating shaft l and the internal bearing cover 4. The outside air that enters the rotating electric machine cools the inside of the machine and is released to the outside together with the exhaust gas.

Therefore, outside air will not enter into the rolling bearing 2 portion surrounded by the lubricant filling chambers 6 and 7, and therefore, contamination and deterioration of the lubricant and damage to the rolling bearing 2 are prevented, and the lubricant is This makes it possible to extend the period for replacement and disassembly of the bearing device.

Although long-term maintenance-free operation has been achieved to some extent, long-term maintenance-free operation still lacks reliability.

That is, when assembling the bearing device, the lubricant filling chambers 6, 71 and the rolling bearing 2 are filled with grease, but if excess grease can be filled, the excess grease is removed during operation of the rotating electric machine. The outside of the lubricant filling chamber 6.7, that is, the partition walls 6W, 7
It leaks into each air chamber 8.9 from the gap between W and the rotating shaft 1. To reduce this leakage, partition walls 6W, 7W
It is possible to reduce the gap between the and the rotating shaft l, but since both are often made of metal, there is a natural limit of 1), currently 0.4~
The minimum value is about 0.5 m.

Incidentally, since outside air containing dust for operating the rotating electric machine is flowing in each of the air chambers 8 and 9, this dust easily adheres to leaked grease. □The dust that adheres to the leaked grease further absorbs the grease and wets the surface of the dust with the grease. New dust adheres to the surface of this wet dust, and as a result of this repetition, the flow path of air due to fluctuations in air pressure is blocked. For example, if the air chamber 9 is clogged, Negative pressure acts on the gap between the partition wall 6W of the lubricant filling chamber 11 and the rotating shaft l, sucking out the grease in the lubricant filling chamber 6 and pulling it out into the rotating electric machine. There may be grease leakage from inside the lubricant filling chamber 6.
This means that there is air flowing through the lubricant filling chamber 7 on the opposite side and the rolling bearing 2, or that there is air intrusion into the lubricant filling chamber 7. Therefore, the grease filling part is filled with outside air containing foreign matter. This results in contamination and deterioration of the grease.

Furthermore, the dust that adheres and accumulates in the air chambers 8 and 9 absorbs even the base oil that is separated from the grease and contributes to the lubrication of the rolling bearing 2, resulting in burnout caused by insufficient lubrication of the rolling bearing 2. There was a strong possibility that this would lead to the above, and there were parts that lacked reliability.

In addition, as mentioned above, the clearance between the rotating shaft 1 and the partitions J16w and J7w is within the range of 0.4 to 0.5, so that the breathing effect during operation of the rotating electric machine or when starting and stopping, or during operation. Due to temperature rise, etc., the base oil may gradually flow out, causing a lack of lubrication.

The above explanation concerns a so-called lubricant-filled bearing device in which grease is filled from the beginning, but the exact same phenomenon can be seen in a lubricant-filled bearing device in which grease can be replenished intermediately. However, in the case of lubricant-filled bearing devices, leakage of excess grease into the air chamber is seen during intermediate replenishment of grease, which is somewhat different from the lubricant-filled bearing devices described above, but there are disadvantages due to dust accumulation, and rotation Shaft 1 and partition wall 6
The drawback is that the base oil gradually flows out from the gap between w and 7w.

As shown in FIGS. 4 and 5, the lubricant replenishment type bearing device is a lubricant filled type bearing device provided with a replenishment path 11 and a side warm lubricant filling chamber 12. The auxiliary i-path 11 has an internal bearing cover 4. Bearing box 3. The external shaft is provided in communication with the receiving cover 5, and its inner end is connected to the upper part of the lubricant chamber 6, and its outer end is connected to the grease nipple GN.

As shown in FIG. 5, the side temperature lubricant filling chamber 12 is provided adjacent to the lubricant filling chamber 70 in the radial direction and in the horizontal direction, and communicates with the lubricant filling chamber 70 through a plurality of communication holes 12A and 12B. It is designed to store grease. In the case of a lubricant filled type bearing device, this side warm lubricant filling plug 12 can be filled with grease.

The above prior art is disclosed in Japanese Patent Publication No. 47-38667.

This is disclosed in Japanese Patent Publication No. 52-27292.

Further, Japanese Utility Model Application Publication No. 55-167748 discloses a bearing device for a rotating electric machine in which pleats made of rubber or the like are pasted on the inner peripheral side of a grease sealing plate facing the shaft. An example of this is shown in FIG. In the figure, 80 is a grease sealing plate, 80A is a fold attached to the inner circumferential side of the grease sealing plate 80, and 90 and 91 are collars fitted into the rotating shaft.

This example attempts to prevent grease leakage by reducing the gap between the rotating shaft side and the enclosing plate side, and also to prevent dust from entering from the outside, but considering the shape of the grease enclosing plate, The amount of grease that can be filled is smaller than that of the prior art described above, and it is not suitable for long-term non-decomposition, and furthermore, it has the disadvantage that intermediate oiling is not possible. Furthermore, since the pleats made of rubber or the like are pasted onto the grease sealing plate, if the folds are damaged, it becomes necessary to replace the entire set of grease sealing plates, which is uneconomical.

In addition, since the depth of these folds is deep and the walls that make up the folds are thin, they are weak in strength and have many chances of being damaged during assembly and disassembly. Coupled with the fact that it has to be affixed to the surface, it is extremely uneconomical.

In addition, in this example, rubber or the like is used to reduce the distance from the rotating shaft side, and this is a non-contact seal, and the rubber elasticity is not particularly intended to be applied. Base oil leakage cannot be completely eliminated.

[Purpose of the invention]

The present invention was made in view of the above points, and its purpose is to prevent the base oil in the lubricant from leaking out, to enable long-term maintenance-free operation, and to prevent foreign substances from entering the filled lubricant. To provide a bearing device for a rotating electric machine in which lubricant does not deteriorate due to intrusion and rolling bearings are not damaged.

[Summary of the invention]

In the present invention, an annular rubber elastic body is provided between the inner diameter side of a lubricant filling chamber facing the side surface of a rolling bearing and the rotating shaft so as to substantially contact the rotating shaft, and the rubber elastic body is arranged in a thickness direction of the rolling bearing. By having unevenness on the surface in a shallower area than the center of the surface, the desired purpose is achieved.

That is, a rubber elastic oil seal T is fixed to the inner diameter side of a lubricant filling chamber provided opposite to the side surface of the rolling bearing, and a minimum tightness or minimum clearance is maintained between it and the rotating shaft. The above-mentioned lubricant filling chamber and air chamber are 0.1 to 0.2 am when the partition wall, oil cool inner diameter surface, and rotating shaft are new.
A certain amount of tightening allowance is provided, and as the oil cooler is used, the tightening allowance will gradually decrease, and eventually the gap will be reduced to 1.
However, in reality, due to the radial clearance of the rolling elements, the maximum clearance is approximately 0.1 tm, which is extremely small compared to the clearance between metals in conventional technology. Therefore, there is no leakage of lubricant or base oil from the lubricant filling chamber, and there is no intrusion of foreign matter, so normal lubrication conditions can be maintained for a long period of time. Since there is no leakage of lubricant or base oil, the air chamber remains dry at all times, and foreign matter that enters the air chamber is carried out of the air chamber with the flow of air. There is no accumulation, and the long-term effectiveness of the air chamber and air flow path can be guaranteed.

[Embodiments of the Invention] The present invention will be described in detail below based on embodiments of the drawings. Incidentally, the same reference numerals are used for the same parts as in the past.

An embodiment of the present invention is shown in FIG. 11, FIG. 2, and FIG. 3.

In FIG. 1, the oil seal 100 is a feature of this embodiment, and the oil seal 100 has a bearing cover 40 located on both sides of the rolling bearing. and a lubricant filling chamber 60 provided in 50. and 70 on the inner diameter side. The details of this oil seal 100 are shown in FIG. 2, but generally a metal ring 100B is provided on the outer diameter side to ensure reliable fixation to the shaft and bearing covers 40 and 50.

The material of the main body 100D of the oil cool 100 is generally determined depending on the intended use, such as a rubber elastic material, and the conditions of use. Furthermore, lips 100A and 100B are provided on both sides of the inner diameter side, that is, the surface facing the rotating shaft 1,
This part comes into contact with the rotating shaft 1. Therefore, the lip on one side prevents the lubricant and base oil from flowing out, and the lip on the other side prevents foreign matter contained in the outside air from entering. Furthermore, several labyrinths 100C are provided between the lips 100A and 100B to strengthen the sealing effect. Rotating shaft 1 and bearing box 3 in FIG. Air chamber 8.9, air flow path 10. The structure and purpose of the supply path 11 are the same as those shown in FIG. 4 above, so a description thereof will be omitted here.

According to this embodiment, since the part in contact with the rotating shaft is the lip of the oil cool, which is a rubber elastic body, the minimum gap can be maintained, and the lubricant and base oil can be prevented from flowing out from the lubricant filling chamber. Since there is no foreign matter entering from the outside, a good lubrication state can be maintained for a long period of time. In addition, since there is no leakage of lubricant or base oil, the air chamber is always kept dry and the air flow path is not blocked, so the effect can be expected for a long period of time.

The above explanations are for lubricant replenishment type bearing devices, but they can of course also be applied to lubricant replenishment type bearing devices that do not have a replenishment path, and the effects may change. do not have.

〔Effect of the invention〕

According to the bearing device for a rotating electrical machine of the present invention as described above, the annular rubber elastic body is placed between the inner pole side of the lubricant filling chamber facing the side surface of the rolling bearing and the rotating shaft, and is substantially in contact with the rotating shaft. The rubber elastic body prevents foreign matter from entering the filled lubricant, degrading the lubricant and damaging the rolling bearing. Therefore, it is very effective for bearing devices of this type of rotating electric machine.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an embodiment of a bearing device for a rotating electrical machine according to the present invention, FIG. 2 is a cross-sectional view showing an example of an oil seal employed therein, and FIG. 3 is a line shown along the line ■-■ in FIG. Cross section, 4th
The figure is a cross-sectional view showing a conventional rotating electric machine Q bearing device, FIG. 5 is a cross-sectional view taken along the line I--I, and FIG. 6 is a cross-sectional view showing another conventional example. 1... Rotating shaft, 2... Rolling bearing, 3... Bearing box,
8, 9... Air chamber, 10... Air flow path, 11...
Supply path, 40...Inner bearing cover, 50...Outer bearing cover, 60...Lubricant filling chamber, 70...Lubricant filling chamber, 100...10th third

Claims (1)

[Claims] 1. A rolling bearing that supports a rotating shaft and is supported by a fixed part, a lubricant filling chamber facing a side surface of the rolling bearing, and a partition wall forming the lubricant filling chamber. In a bearing device for a rotating electrical machine, the bearing device includes an air chamber provided outside the partition wall, and an air flow path communicating with the air chamber, wherein an annular ring is provided between the inner diameter side of the lubricant filling chamber and the rotating shaft. A bearing device for a rotating electric machine, characterized in that a rubber elastic body is provided so as to be substantially in contact with the rotating shaft, and the rubber elastic body has irregularities on its surface in a shallower range than the center in the thickness direction. 2. The rotation according to claim 1, characterized in that a lip-shaped convex portion is provided on both end surfaces of the inner diameter side of the rubber elastic body, and the inner diameter surface of the convex portion and the rotating shaft are substantially in contact with each other. Bearing devices for electrical machinery.