JPH0426736Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an improvement in bearing seals attached to both ends of a bearing body.

(Prior Art) A conventional example of this type of bearing is one shown in FIG. 3, for example. That is, FIG. 3 is a longitudinal cross-sectional view of the main parts of a conventional bearing seal, and the bearing seal 110 includes a seal case 111 attached to a bearing body (not shown) and a spring cover 112 fixed to the inner circumferential side of the seal case 111. An oil seal 113 is held between the bearings, and the bearing seals 110 are attached to both ends of the bearing body. Furthermore, the third
In the case of the bearing seal 110 shown in the figure, A
The side B is the bearing body side, and the B side is the atmosphere side.

(Problem to be solved by the invention) However, the conventional bearing seal 110
In this case, since the oil seal 113 is fixed on the stationary side and is in sealing contact with the surface of the rotating member, it may be possible to prevent water, dust, etc. from the atmospheric side from entering the valve bearing body. There is a problem in that it is not possible to completely prevent the infiltration of gases such as water vapor that are generated when snow removal is performed using heating means. In this way, when gas containing moisture such as water vapor enters and stagnates inside the bearing, the temperature inside the bearing rises due to the heat generated by the rolling elements when the axle rotates at high speed, and the temperature between it and the atmosphere increases. When a difference occurs, water vapor or the like inside the bearing comes into contact with the low-temperature seal case 111, causing dew condensation on its inner peripheral surface. Particularly during the cold season when the temperature on the atmospheric side is extremely low, the temperature difference between the inside and outside of the bearing is significant, and the amount and range of dew condensation that occurs inside the bearing becomes large.

When the dew condensation thus generated inside the bearing becomes water droplets due to steam saturation and mixes into the grease that lubricates the bearing, it causes the grease to emulsify. When grease is emulsified, its lubrication function is significantly reduced, causing problems such as seizure of bearings.

The present invention was developed in view of the above problem, and its purpose is to prevent the formation of dew condensation inside the bearing by preventing a temperature difference between the atmosphere side and the inside of the bearing. To provide a bearing seal that can prevent emulsification of lubricant and reliably prevent accidents such as seizure of the bearing.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides an annular seal case and a fixing member fixed to the inner circumference of the seal case at the side end of the outer ring of the bearing body that holds the rotating shaft. By providing a stationary member having a ring,
A space is formed between a rotating body fixed to a rotating shaft and a stationary member, and an oil seal is fitted in a position facing the space around the outer periphery of the rotating body, and the oil seal is provided with:
A first auxiliary lip portion is provided which does not contact the stationary member when the rotating body is not rotating, and which is elastically deformed by centrifugal force and comes into contact with the stationary member when the rotating body rotates, and further includes a fixed ring that is larger than the first auxiliary lip. The bearing is characterized in that a seal lip that slides into contact with the rotating body is attached to the inside of the bearing body.

(Function) Since the oil seal rotates together with the rotating body, there is no leakage of water etc. between the two, and while the rotating shaft is rotating, the first auxiliary lip provided on the oil seal is elastically deformed by centrifugal force and comes into contact with other stationary members such as the seal case to prevent water, dust, etc. from entering the bearing body. However, gas such as water vapor that has passed through the first auxiliary lip portion of the oil seal and entered between the seal case and the fixed ring is prevented from entering the inside of the bearing body by the seal lip. Then, when the rotating shaft is stopped, no centrifugal force acts on the oil seal, and the first auxiliary lip portion returns to a position away from the stationary member, forming a gap there. Therefore, the gas is discharged to the atmosphere through this gap, and no temperature difference is generated between the bearing and the atmosphere, so that no dew condensation occurs inside the bearing. Therefore, the function of lubricants such as grease is not impaired.

(Example) The present invention will be explained below based on the illustrated example.

Fig. 1 is a longitudinal sectional view of the lower half of the journal bearing equipped with the bearing seal according to the present invention;
The figure is a longitudinal sectional view of the main parts of the bearing seal.

A journal bearing 1 shown in FIG. 1 rotatably supports one end of a rotating shaft 30.
Bearing seals 10, 10 according to the present invention are attached to both ends of the bearing body 2 constituting the journal bearing 1.

The bearing main body 2 is constructed by interposing a plurality of rolling elements 5 between a stationary outer ring 3 and inner rings 4 fixed to the outer periphery of a rotating shaft 30 so as to be freely rolling.
In Fig. 1, 6 and 6 are retainers for holding the rolling elements 5 between the outer ring 3 and the inner ring 4 at a predetermined pitch in the circumferential direction, and 7 is interposed between the inner rings 4 and 4. It is a distance piece.

Furthermore, seal ring rotating bodies 31 and 32 are fitted onto the outer periphery of the rotating shaft 30, and one end surface thereof abuts the inner rings 4 and 4, respectively. Bearing seals 10, 10 connected to the bearings are in sliding contact with each other.

By the way, as shown in FIG. 2, each of the bearing seals 10 includes an annular seal case 11 attached to the side end of the outer ring 3, and a spring cover 12 as a fixed ring fixed to the inner circumferential side of the seal case 11. a stationary member consisting of a seal ring 31;
An oil seal 13 is disposed in a closed cross-sectional space formed between Therefore, the oil seal 13 rotates together with the seal ring 31, that is, together with the rotating shaft 30. Further, a predetermined gap is formed between the end of the oil seal 13 on the atmosphere side and the outer periphery thereof on the atmosphere side, as shown in the figure, between the seal case 11 and the stationary member of the spring cover 12 when the rotating shaft 30 is stopped. First auxiliary lip portions 13a and 13b that are separated from the stationary member are integrally formed, and a second auxiliary lip portion 13c that comes into contact with the inner surface of the spring cover 12 when the oil seal 13 is stopped is formed on the outer periphery of the oil seal 13 on the bearing body side. It is formed in one piece.

On the other hand, a seal lip 15 that is to be in sliding contact with the outer periphery of the seal ring 31 is attached to a position closer to the inside of the bearing body 2 than the first auxiliary lip parts 13a, 13b, that is, around the free end of the spring cover 12. There is. In addition, in Figure 2, 16..., 17
. . . is a projection for positioning the oil seal 13. Further, through holes 18 are bored at the lower circumferential position of the seal case 11.

In the bearing seal 10 shown in FIG. 2, A is the inside of the bearing body, and B is the atmosphere side. Furthermore, although the above has been described only for one of the bearing seals 10 (the one on the seal ring 31 side), the structure of the other bearing seal (the one on the seal ring 32 side) is also the same as above, so a description thereof will be omitted. do.

Next, the function of this bearing seal 10 will be explained.The inner circumference of the oil seal 13 is its main lip portion a,
Since the oil seals b and c are watertightly and airtightly fitted to the outer periphery of the seal ring 31, gases such as water and steam cannot leak between these oil seals 13 and the seal ring 31.

By the way, when the rotating shaft 30 rotates, the oil seal 13 also rotates, so the oil seal 13
First auxiliary lip portions 13a, 13 integrally formed with
b both expand radially outward (elastically deform) under the influence of centrifugal force, and come into close contact with stationary members of the seal case 11 and spring cover 12, respectively. Therefore,
Moisture, etc. in the atmosphere is removed by the first auxiliary lip portion 13a,
13b prevents it from entering the seal case 11. In addition, in the unlikely event that these lip portions 13a,
Gas and the like that have entered the seal case 11 through the seal ring 13b are normally prevented from entering the bearing body 2 by the seal lip 15 that comes into contact with the seal ring 31.

Therefore, when the rotating shaft 30 is stopped, no centrifugal force acts on the oil seal 13, so that the first auxiliary lip portion 13 provided on the oil seal 13
a and 13b are seal case 1 as shown in FIG.
1. The spring cover 12 is restored to a position away from the stationary member, and a gap is created between the two, so that the internal space communicates with the atmosphere. Therefore, the pressure of gas such as water vapor that has entered the seal case 11 through the first auxiliary lip portions 13a and 13b during the rotation of the rotating shaft 30 increases due to the temperature rise inside the bearing. Since it is effectively discharged into the atmosphere through this gap or through hole 18, there is no difference in temperature between the air and the atmosphere. Furthermore, since the second auxiliary lip portion 13c is in close contact with the spring cover 12 on the stationary side when the shaft is stopped, even if the above-mentioned gas is not sufficiently discharged, it will still enter the inside of the bearing body 2. There's nothing to do. or,
The seal lip 15 prevents gas that has entered the seal case 11 from entering the bearing body 2, and also prevents lubricant such as grease from leaking out of the bearing body 2.

(Effects of the invention) As is clear from the above explanation, according to the invention,
Since there is no temperature difference between the atmosphere side and the inside of the bearing, there is no condensation inside the bearing, which prevents lubricants such as grease inside the bearing body from being adversely affected by moisture. , its lubrication performance is not impaired, and accidents such as bearing seizure are prevented from occurring. Furthermore, since the oil seal rotates together with the rotating shaft and has few sliding parts, the durability of the bearing seal is improved.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of the lower half of the journal bearing equipped with the bearing seal according to the present invention;
This figure is a longitudinal sectional view of the main part of the bearing seal, and FIG. 3 is a longitudinal sectional view of the main part of the conventional bearing seal. 1... Journal bearing, 10... Bearing seal, 11... Seal case, 12... Spring cover, 13... Oil seal, 13
a, 13b...first auxiliary lip part, 13c...second auxiliary lip part, 15...seal lip, 18...
...through hole.

Claims (1)

[Scope of utility model registration request] A rotating body fixed to the rotating shaft is provided by providing a stationary member having an annular seal case and a fixed ring fixed to the inner circumference of the seal case at the side end of the outer ring of the bearing body that holds the rotating shaft. A space is formed between the rotating body and the stationary member, and an oil seal is fitted in a position facing the space around the outer periphery of the rotating body. a first auxiliary lip portion that is elastically deformed by force and comes into contact with the stationary member;
A bearing seal further comprising a seal lip which is to be in sliding contact with a rotating body and is attached to the fixed ring at a position closer to the inside of the bearing body than the first auxiliary lip.