JP2007120640A - Rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing whose maintenance cycle is elongated by an appropriate clearance formed between a rotation side bearing ring and a sealing member. <P>SOLUTION: A cylindrical roller bearing comprises: an inner ring 22 as a rotation side bearing ring; an outer ring 23 as a non-rotation side bearing ring with insulating layers on its outer diameter surface and both end surfaces; cylindrical rollers 24 as rolling elements disposed between the inner ring 22 and the outer ring 23; a cage 25 keeping intervals between the cylindrical rollers 24; and sealing seals 26 as sealing members with U-shaped cross-sectional surfaces projected from axial both ends of the inner ring 22 and the outer ring 23. A clearance δ between a wall face opposed to the inner ring 22 of the sealing seal 26 and the raceway surface of the inner ring 22 is set within a range of 0.003≤δ/d≤0.015, when the inner diameter of the sealing seal 26 is d. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a rolling bearing, and more particularly to a rolling bearing that requires a longer lubrication life in grease lubrication.

  Conventionally, cylindrical roller bearings and deep groove ball bearings have been used as bearings used in railway vehicle main motors. For example, a cylindrical roller bearing 1 as shown in FIG. 4 maintains an interval between an inner ring 2, an outer ring 3, a cylindrical roller 4 as a rolling element disposed between the inner ring 2 and the outer ring 3, and the cylindrical roller 4. And a cage 5.

  In addition, the cylindrical roller bearing 1 used in the railway car main motor has an insulating layer 3a formed on the outer diameter surface and both end surfaces of the outer ring 3 in order to prevent damage to the bearing due to electrolytic corrosion. The insulating layer 3a is formed by spraying an insulating material such as ceramics.

  Furthermore, since the railway vehicle main motor is used outdoors, there is a concern that grease may deteriorate due to dust contamination in an open type bearing in which a grease pocket is formed in the bearing peripheral structure. Therefore, it is preferable to use a sealed bearing in order to prevent the grease from being deteriorated due to dust and to extend the maintenance cycle.

  However, in the case of the cylindrical roller bearing 1 configured as described above, since the bearing internal space volume is small, there is a problem in that an appropriate amount of grease cannot be sealed to ensure the bearing life required for the railway vehicle main motor bearing. is there. This problem applies to ball bearings as well.

  As a means to solve the above problem, it is conceivable to increase the filling ratio of the grease with respect to the internal space volume. In this case, however, the agitation resistance of the grease increases at the time of rotation of the bearing, particularly at the start, and the temperature of the bearing rapidly increases. Is not appropriate.

  In view of this, a rolling bearing capable of securing an appropriate amount of grease inside the bearing is described in, for example, Japanese Patent Application Laid-Open No. 2004-346972 (Patent Document 1).

As shown in FIG. 5, the cylindrical roller bearing 11 described in the publication has an inner ring 12, an outer ring 13, a cylindrical roller 14 disposed between the inner ring 12 and the outer ring 13, and the interval between the cylindrical rollers 14. A retainer 15 to be held and sealing seals 16 disposed at both axial ends of the inner ring 12 and the outer ring 13 are provided, and the outer diameter surface and both end surfaces of the outer ring 13 are covered with an insulating material 17. Further, the sealing seal 16 has a U-shape projecting from both end faces of the inner ring 12 and the outer ring 13, and is fixed to the outer ring 13 by a stopper 16a.
JP 2004-346972 A

  When the cylindrical roller bearing 11 as shown in FIG. 5 is rotated, the outer ring 13 and the seal 16 are stationary, and the inner ring 12 is rotated with the rotation of the shaft. Therefore, in order to prevent the sealing seal 16 from being damaged due to contact between the inner ring 12 and the sealing seal 16, it is necessary to provide a certain gap between the inner ring 12 and the sealing seal 16.

  If this gap is too small, the inner ring 12 and the sealing seal 16 may come into contact with each other during rotation of the bearing due to manufacturing errors of the sealing seal 16 or the like. On the other hand, if the gap is too large, leakage of grease and entry of dust from the outside cannot be prevented.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a rolling bearing having an extended maintenance cycle by providing an appropriate gap between the rotating side race and the sealing member.

  The rolling bearing according to the present invention protrudes in a substantially U-shaped cross-sectional shape from the end surfaces of both the bearing rings, the rotating bearing rings, the non-rotating bearing rings, the rolling elements disposed between the both bearing rings. And a ring-shaped sealing member. The inner diameter dimension d of the sealing member and the gap δ between the wall surface facing the rotation-side raceway of the seal member and the rotation-side raceway have a relationship of δ / d ≦ 0.015.

  By setting the gap δ between the inner ring and the sealing member within the above range, it is possible to effectively prevent leakage of grease sealed inside the bearing and entry of dust from the outside of the bearing. As a result, a rolling bearing with an extended maintenance cycle can be obtained.

  Preferably, the inner diameter dimension d of the sealing member and the gap δ between the wall surface of the sealing member facing the rotation-side raceway and the rotation-side raceway have a relationship of δ / d ≧ 0.003. From the viewpoint of the sealing performance of the sealing member, the smaller the gap between the inner ring and the sealing member, the better. However, in consideration of the manufacturing error of the sealing member, δ = 0 cannot be set. Therefore, by setting the gap δ between the inner ring and the sealing member within the above range, even if there is a certain manufacturing error in the sealing member, it is possible to prevent the inner ring and the sealing member from contacting when the bearing rotates. Can do.

  Preferably, the sealing member is made of a resin material. By using a resin with high insulation performance as the material of the sealing member, a rolling bearing that can be used for a railway vehicle main motor or the like can be obtained.

  For example, the rotation-side raceway is an inner ring, and the non-rotation-side raceway is an outer ring. Thereby, when using as a bearing which supports the rotating shaft etc. of a railway vehicle main motor, a maintenance period can be extended, for example.

  According to the present invention, a rolling bearing having an extended maintenance cycle can be obtained by setting the gap δ between the inner ring and the sealing member within a range of 0.003 ≦ δ / d ≦ 0.015.

  With reference to FIGS. 1-3, the cylindrical roller bearing 21 which concerns on one Embodiment of this invention is demonstrated.

  As shown in FIG. 2, the cylindrical roller bearing 21 includes an inner ring 22 as a rotating raceway, an outer ring 23 as a non-rotating raceway having an outer diameter surface and both end faces, and an inner ring 22 and an outer ring. A cylindrical roller 24 serving as a rolling element disposed between the rollers 23, a cage 25 for maintaining the interval between the cylindrical rollers 24, and both axial ends of the inner ring 22 and the outer ring 23 project in a U-shaped cross-sectional shape. And a hermetic seal 26 as a sealing member.

  The hermetic seal 26 has a ring shape protruding from both end faces of the inner ring 22 and the outer ring 23 with a substantially U-shaped cross-sectional shape. The inside of the substantially U-shaped projection becomes a grease pocket, and an appropriate amount of grease can be sealed inside the bearing. In this specification, the “substantially U-shaped” is not limited to the U-shaped shape such as the sealing seal 26 shown in FIG. Any shape that protrudes from this part shall be included.

  Moreover, it has the weir 27 which protrudes from an inner wall surface, and as shown in FIG. 3, the division | segmentation area | region 27a divided | segmented into the circumferential direction by the weir 27, and the opening end of the sealing seal 26 as shown in FIG. On the side, a continuous region 27b communicating between the adjacent divided regions 27a and a grease injection port (not shown) are provided at at least one location on the wall surface of the seal seal 26.

  Further, as shown in FIG. 1, the gap δ between the wall surface facing the inner ring 22 of the seal seal 26 and the raceway surface of the inner ring 22 is 0.003 ≦ δ / d ≦ where the inner diameter dimension of the seal seal 26 is d. Set within the range of 0.015.

  By setting the gap δ between the inner ring 22 and the hermetic seal 26 within the above range, the maintenance cycle of the cylindrical roller bearing 21 can be extended. If δ / d ≦ 0.003, the inner ring 22 and the sealing seal 26 may come into contact with each other during rotation of the bearing due to manufacturing errors of the sealing seal 26 and the like. On the other hand, when δ / d ≧ 0.015, it is not possible to prevent leakage of grease sealed inside the bearing and contamination of dust from the outside of the bearing. As a result, the bearing life is reduced in any case.

  In the cylindrical roller bearing 21 shown in FIG. 2, the portion of the inner ring 22 facing the sealing seal 26 is a raceway surface. However, in the case of an inner ring having flanges at both ends, the wall surface facing the inner ring of the sealing seal And δ is defined as the gap between the inner ring and the outer diameter surface of the flange portion of the inner ring.

  Further, by dividing the grease pocket into a plurality of divided regions 27a, even when the viscosity of the grease decreases during the rotation of the bearing, it is possible to prevent the grease sealed in each divided region 27a from flowing out to the other divided regions 27a. Grease can be held evenly.

  When filling the sealing seal 26 with grease, first, the opening end of the sealing seal 26 is sealed with a seal or the like, and the grease is injected from the grease inlet. The grease injected into the hermetic seal 26 first fills one divided region 27a and then moves to the left and right divided regions 27a via the continuous region 27b. When all the divided areas 27a are filled with grease, the seal at the open end is removed to remove excess grease in the continuous area 27b.

  As described above, by providing the continuous region 27b communicating between the adjacent divided regions 27a, it is possible to fill all the divided regions 27a with grease from one grease injection port. As a result, the structure of the hermetic seal 26 and the grease filling operation can be simplified. Further, by providing the continuous region 27b on the opening end side of the hermetic seal 26, the excessively filled grease can be easily removed, so that an appropriate amount of grease can be sealed.

  3 shows an example in which the weir 27 is provided evenly on the circumference of the hermetic seal 26. However, the weir 27 is not limited to this example, and the weir 27 is placed in a position where the grease can be effectively prevented from being biased. Any number of weirs 27 may be provided.

  The hermetic seal 26 may be manufactured by pressing a metal, or may be manufactured by covering a metal cored bar with an insulating material such as rubber, but from the viewpoint of improving the insulating performance of the bearing. Is preferably manufactured by injection molding of a resin material.

  In the above embodiment, the example of the cylindrical roller bearing 21 has been described. However, the present invention is not limited to this, but a tapered roller bearing, a self-aligning roller bearing, a deep groove ball bearing, a four-point contact ball bearing, an angular ball bearing, etc. Regardless of whether the moving body is a roller or a ball, it can be applied to any rolling bearing.

  Further, in the above embodiment, an example of the cylindrical roller bearing having the insulating layer on the outer diameter surface and both end surfaces of the outer ring is shown. However, the present invention is not limited to this, and the insulating layer is formed on the inner diameter surface and both end surfaces of the inner ring. It is good to do. Since the inner ring inner surface has a smaller spray area than the outer ring outer surface, the thermal spraying cost can be reduced by spraying the insulating material onto the inner ring inner surface. In addition, since the insulating layer does not interfere with the joint between the hermetic seal and the race, the method for fixing the hermetic seal can be simplified.

  Furthermore, in the above-described embodiment, an example in which the inner ring 22 is a rotation side raceway and the outer ring 23 is a non-rotation side raceway and the sealing seal 26 is fixed to the outer race 23 is shown. However, the present invention is not limited to this. The present invention can also be applied to a gap between a seal seal of a bearing in which a seal seal is fixed to the inner ring and the outer ring, where the inner ring is a non-rotating side race and the outer ring is a rotation side race.

  As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to the thing of embodiment shown in figure. Various modifications and variations can be made to the illustrated embodiment within the same range or equivalent range as the present invention.

  The present invention is advantageously used for rolling bearings used in railway vehicle main motors and the like.

It is a figure which shows the characterizing part of this invention, Comprising: It is an enlarged view of the P section of FIG. It is a figure which shows the cylindrical roller bearing which concerns on one Embodiment of this invention. FIG. 3 is a front view of a hermetic seal used in FIG. 2. It is a figure which shows the conventional standard roller bearing. It is a figure which shows the example of the roller bearing which made the seal seal protrude from the end surface of an inner ring | wheel and an outer ring | wheel, and enlarged the bearing internal space.

Explanation of symbols

  1,11,21 Cylindrical roller bearing, 2,12,22 Inner ring, 3,13,23 Outer ring, 3a, 13a, 23a Insulating layer, 4,14,24 Cylindrical roller, 5,15,25 Cage, 16,26 Hermetic seal, 16 stop, 27 weir, 27a split region, 27b continuous region.

Claims (4)

A rotating raceway,
A non-rotating side ring,
Rolling elements disposed between the two race rings,
A ring-shaped sealing member that protrudes from the end faces of the both race rings in a substantially U-shaped cross-sectional shape,
An inner diameter dimension d of the sealing member, and a gap δ between the wall surface of the sealing member facing the rotating raceway and the rotating raceway,
δ / d ≦ 0.015
Rolling bearings with the relationship An inner diameter dimension d of the sealing member, and a gap δ between the wall surface of the sealing member facing the rotating raceway and the rotating raceway,
δ / d ≧ 0.003
The rolling bearing according to claim 1, having the relationship:   The rolling bearing according to claim 1, wherein the sealing member is formed of a resin material. The rotating side raceway is an inner race,
The rolling bearing according to claim 1, wherein the non-rotating side race is an outer ring.

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