JP2004036727A - Sealed rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive sealed rolling bearing capable of preventing a bearing outer part from being fouled by the leakage of lubricating oil by increasing a sealability. <P>SOLUTION: In this sealed rolling bearing 41, openings at both ends of the bearing are closed by a shield plate 54 fitted to both end outer peripheral parts of an inner ring and an oil seal 55 fitted to a seal mounting step part 48 at both end inner peripheral part of an outer ring 47. The oil seal 55 comprises an elastic member having a first lip part 61 for sealing, a second lip part 63 for sealing, and a packing part 65 pressed against the side face 48b of the seal mounting step part 48, and is formed integrally onto a single metal ring 71 for locking an outer peripheral flange part 71a to the seal mounting step part 48. The shield plate 54 comprises a disk part 54b installed extendedly in a radial outer direction so as to cover the openings at both ends of the bearing and having an inner surface in slidable contact with the second lip part 63 for sealing and a cylindrical part 54c installed projectedly from the inner surface of the disk part 54b toward the inside of the bearing and having an outer peripheral surface in slidable contact with the first lip part 61 for sealing. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a sealed rolling bearing, and more particularly to an improvement for preventing contamination of the outside of a bearing due to leakage of lubricating oil by improving sealing performance.
[0002]
[Prior art]
FIG. 3 shows a conventional example of an outer ring rotating type sealed rolling bearing in which an outer ring is used as a roll for rolling in a rolling facility such as a cluster mill.
As shown in FIG. 3, the sealed rolling bearing 11 includes an inner ring 15 composed of two inner race units 13 and 14 arranged in the axial direction, a single outer ring 17, and these inner and outer rings 15 and 17. A double-row cylindrical roller bearing provided with cylindrical rollers 19 provided in two rows between the rollers, a retainer 21 for maintaining the interval between the cylindrical rollers 19 in each roller row, and a sealing mechanism 23 for closing openings at both ends of the bearing. is there.
[0003]
In the sealed rolling bearing 11, for example, a shaft that is a non-rotating shaft is press-fitted into the inner race 15, while the outer race 17 is used as a roll for rolling, and each inner race ring unit constituting the inner race 15 is formed. Oil supply passages 13a and 14a and oil discharge passages 13b and 14b penetrating in the radial direction are provided in 13 and 14, respectively.
[0004]
The oil supply passages 13a and 14a and the oil discharge passages 13b and 14b communicate with the shaft (not shown) which is press-fitted to the inner ring 15 and the oil supply port and the oil discharge port of the lubricating oil circulation device provided outside, respectively. An oil supply path and an oil discharge path for causing the oil to flow are provided. Then, oil supply / discharge to / from the inside of the bearing is performed via an oil supply path and an oil discharge path formed between the inner ring 15 and a shaft fitted to the inner ring 15.
[0005]
The sealing mechanism 23 includes a shield plate 24 in which a fitting surface 24 a is fitted to the outer peripheral surface 15 a at both outer peripheral portions of the inner ring 15 by interference fit, and a seal mounting step portion 18 at both inner peripheral portions of the outer ring 17. And an oil seal 25 to be attached.
[0006]
As shown in FIG. 4, the oil seal 25 includes a first sealing lip portion 31 protruding radially inward and a second sealing lip portion 33 protruding axially outward. Have.
The first sealing lip portion 31 and the second sealing lip portion 33, which are made of an elastic member, are separate from each other and are arranged side by side along the axial direction. The core is integrally formed, for example, by insert molding.
[0007]
The metal ring 36 is prevented from moving in the axial direction by engaging an outer peripheral flange portion 36a formed on the inner end side of the cylindrical portion 36b with a locking groove 18a formed in the seal mounting step portion 18. Being restrained. Further, the metal ring 36 has an inner peripheral flange portion 36 c extending radially inward at an outer end side of a cylindrical portion 36 b extending outward in the axial direction between the side surface 18 b of the seal mounting step 18. A space 38 for accommodating and holding the metal ring 35 is formed.
[0008]
In the metal ring 35 having a substantially L-shaped cross section, the cylindrical portion 35a is fitted into the cylindrical portion 36b of the metal ring 36 by interference fit, and the inner peripheral flange portion 35b formed on the inner end side is used for the seal mounting. The metal ring 36 is fitted and mounted so as to be in surface contact with the side surface 18 b of the step portion 18.
[0009]
A disk portion 24b is provided on an outer peripheral portion of the shield plate 24 so as to extend radially outward so as to cover openings at both ends of the bearing, and an inner surface of the disk portion 24b is in sliding contact with the second sealing lip portion 33 of the oil seal 25. And a cylindrical portion 24c protruding from the inner surface of the disk portion 24b to the inside of the bearing and having an outer peripheral surface slidably in contact with the first sealing lip portion 31 of the oil seal 25.
[0010]
[Problems to be solved by the invention]
However, the oil seal 25 in the above-described conventional sealing mechanism 23 has two first lip portions 31 for sealing and a second lip portion 33 for sealing, and separates the metal rings 35 and 36 from each other. Since it is equipped, there is a problem that the number of components increases and the cost increases. Further, between the cylindrical portion 35a of the metal ring 35 and the cylindrical portion 36b of the metal ring 36, the surface roughness of their contact surfaces is improved or the gap is filled with a gap filler so that the lubricating oil does not leak. Or the assembly is not good.
[0011]
The surface between the oil seal 25 and the seal mounting step 18 is a simple surface contact between the inner side surfaces of the metal rings 35 and 36 and the side surface 18b. The sealing performance is not sufficient as compared with the sliding contact portion of the plate 24 with the disk portion 24b.
[0012]
Therefore, when the lubricating oil supplied between the inner and outer wheels flows toward the oil seal 25 due to the centrifugal force at the time of rotation of the outer ring, a part of the lubricating oil is formed between the inner surfaces of the metal rings 35 and 36 and the side surface 18b. The metal rings 35 and 36 are distorted by the pressure of the lubricating oil, the position of the second sealing lip 33 is shifted, and the sealing performance may be deteriorated. Further, when a part of the lubricating oil which has entered between the inner side surfaces of the metal rings 35 and 36 and the side surface 18b reaches the outer peripheral edge of the outer peripheral flange portion 36a, the outer peripheral surface of the cylindrical portion 36b and the seal mounting are performed. There is a risk of leakage to the outside from between the inner peripheral surface of the step portion 18 and soiling of the outside.
[0013]
Further, in the above-described conventional sealing mechanism 23, since the first sealing lip portion 31 and the second sealing lip portion 33 of the oil seal 25 are arranged along the axial direction, the oil seal 25 Becomes larger, the axial length of the cylindrical roller 19 interposed between the outer ring 17 and the inner ring 15 must be reduced accordingly, and it is difficult to increase the load capacity of the bearing. There was also a problem.
[0014]
Accordingly, an object of the present invention is to solve the above-mentioned problems, and to provide an inexpensive sealed rolling bearing capable of improving sealing performance and preventing contamination of the outside of the bearing due to leakage of lubricating oil.
[0015]
[Means for Solving the Problems]
An object of the present invention is to provide a sealing type rolling device in which openings at both ends of a bearing are closed by a shield plate attached to an outer peripheral portion of both ends of an inner ring and an oil seal attached to a step portion for attaching a seal in an inner peripheral portion of both ends of an outer ring. A bearing, wherein the oil seal projects radially inward, a first sealing lip portion, a second sealing lip projecting outward in the axial direction, and the seal mounting step portion. And an elastic member having a packing portion pressed against the side surface of the outer ring, and is integrally formed on a single metal ring that locks the outer peripheral flange portion to the seal mounting step portion of the outer ring, and the shield plate is A disk portion extending radially outward so as to cover the openings at both ends of the bearing, and having an inner surface slidably in contact with the second lip portion for sealing, and projecting inward from the inner surface of the disk portion into the bearing. Is established Circumferential surface is achieved by sealing a rolling bearing, characterized in that it comprises a sliding contact with the cylindrical portion to the first lip portion for the seal.
[0016]
According to the above configuration, the first sealing lip portion and the second sealing lip portion of the oil seal are integrally formed on a single metal ring that is locked to the seal mounting step portion of the outer race. Therefore, the number of components of the oil seal can be reduced and cost can be reduced, and at the same time, the assemblability can be improved.
[0017]
Further, since the packing portion which is in pressure contact with the side surface of the step portion for mounting the seal is integrally formed on the metal ring, it is possible to improve the sealing performance between the side surface of the step portion for mounting the seal and the oil seal. it can.
Therefore, it is possible to prevent the lubricating oil from leaking between the side surface of the seal mounting step portion and the oil seal, thereby preventing the outside of the bearing from being stained by the leaking lubricating oil.
[0018]
Preferably, the first lip portion for sealing and the second lip portion for sealing are arranged so as to be arranged in a radial direction.
In this case, compared to a conventional oil seal in which the first lip portion for sealing and the second lip portion for sealing are arranged side by side along the axial direction, the oil to be mounted on the seal mounting step portion of the outer ring is different. The width dimension of the seal is reduced, and accordingly, the axial length of the rolling element disposed between the inner and outer rings can be increased to increase the load capacity of the bearing.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a sealed rolling bearing according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a longitudinal sectional view of a main part of a sealed rolling bearing according to an embodiment of the present invention, and FIG. 2 is an enlarged view of a main part of the sealed rolling bearing shown in FIG.
[0020]
As shown in FIG. 1, the sealed rolling bearing 41 according to the present embodiment includes an inner ring 45 composed of two inner race units 43 and 44 arranged in the axial direction, a single outer ring 47, and these inner and outer rings. An outer ring rotary type including a cylindrical roller 49 provided in two rows between 45 and 47, a retainer 51 for maintaining the interval between the cylindrical rollers 49 in each roller row, and a sealing mechanism 53 for closing openings at both ends of the bearing. Double-row cylindrical roller bearing.
[0021]
In the sealed rolling bearing 41, for example, a shaft that is a non-rotating shaft is press-fitted into the inner race 45, while the outer race 47 is used as a roll for rolling, and each inner race unit forming the inner race 45 is formed. Oil supply paths 43a, 44a and oil discharge paths 43b, 44b penetrating in the radial direction are provided in 43, 44.
Further, the oil supply passages 43a and 44a and the oil discharge passages 43b and 44b communicate with the shaft (not shown) which is press-fitted to the inner ring 45 and the oil supply port and the oil discharge port of the lubricating oil circulation device provided outside, respectively. An oil supply path and an oil discharge path for causing the oil to flow are provided. Then, oil supply / discharge to the inside of the bearing is performed via an oil supply path and an oil discharge path formed between the inner ring 45 and a shaft fitted to the inner ring 45.
[0022]
The sealing mechanism 53 includes a shield plate 54 in which a fitting surface 54 a is fitted to the outer peripheral surface 45 a at both outer peripheral portions of the inner ring 45 by interference fitting, and a seal mounting step portion 48 at both inner peripheral portions of the outer ring 47. And an oil seal 55 to be attached.
[0023]
As shown in FIG. 2, the oil seal 55 includes a first sealing lip 61 projecting radially inward, a second sealing lip 63 projecting axially outward, and It is made of an elastic member such as synthetic rubber having a packing portion 65 that is in pressure contact with the side surface 48b of the seal mounting step portion 48, and is integrally formed on a single metal ring 71 as a cored bar.
[0024]
The metal ring 71 is formed into a predetermined shape from a metal plate by press molding or the like, and the outer peripheral flange portion 71a is locked in a locking groove 48a formed in a corner of the seal mounting step portion 48. Thus, the removal in the axial direction is restricted.
An inner peripheral flange portion 71b of the metal ring 71, which is formed so that the radial intermediate portion 71c bulges outward in the axial direction, has a predetermined distance from a side surface 48b of the seal mounting step portion 48. The packing portion 65 provided on the inner surface of the inner peripheral flange portion 71b is pressed against the side surface 48b with a predetermined pressing margin.
[0025]
Further, in the metal ring 71, the first sealing lip portion 61 provided on the inner peripheral flange portion 71b and the second sealing lip portion 63 provided on the radially intermediate portion 71c are formed along the radial direction. The cross-sectional shape is set so as to be substantially aligned.
[0026]
The shield plate 54 extends radially outward so as to cover the openings at both ends of the bearing, and has an inner surface slidably in contact with the second sealing lip 63, and a circular plate portion 54b. And a cylindrical portion 54c protruding inward from the inner surface of the bearing and having an outer peripheral surface slidably in contact with the first lip portion 61 for sealing.
[0027]
That is, according to the sealed rolling bearing 41 of the present embodiment, the sealing first lip portion 61 and the sealing second lip portion 63 of the oil seal 55 are engaged with the locking groove of the seal mounting step portion 48 of the outer ring 47. Since it is made of an elastic member such as synthetic rubber integrally formed on a single metal ring 71 locked to the metal ring 48a, the number of components is reduced as compared with the conventional oil seal 25 shown in FIG. At the same time, the assemblability can be improved.
[0028]
Also, since the packing portion 65 which is pressed against the side surface 48b of the seal mounting step portion 48 is integrally formed on the metal ring 71, a gap between the side surface 48b of the seal mounting step portion 48 and the oil seal 55 is formed. Sealing performance can be improved.
That is, even when the lubricating oil supplied between the inner and outer rings 45 and 47 from the oil supply passages 43a and 44a flows toward the oil seal 55 due to the centrifugal force at the time of rotation of the outer ring, the lubricating oil flows inside the metal ring 71. The metal ring 71 does not enter the space between the side surface and the side surface 48b and is distorted by pressure.
[0029]
Therefore, the position of the second sealing lip 63 is not shifted due to the distortion of the metal ring 71 of the oil seal 55, and the deterioration of the sealing performance is not caused. Further, since the lubricating oil cannot enter between the inner side surface of the metal ring 71 and the side surface 48b, the lubricating oil does not go around to the outer peripheral edge of the outer peripheral flange portion 71a and leak to the outside.
Therefore, contamination of the outside of the bearing due to leakage of the lubricating oil from the sealed rolling bearing to the outside can be reliably prevented.
[0030]
Furthermore, the first sealing lip portion 61 and the second sealing lip portion 63 of the oil seal 55 in the present embodiment are arranged so as to be substantially aligned in the radial direction, and the first lip portion 31 for sealing and Compared to the conventional oil seal 25 (see FIG. 4) in which the second sealing lip 33 and the sealing second lip 33 are arranged along the axial direction, the oil seal mounted on the seal mounting step 48 of the outer ring 47. The width dimension W2 of the bearing 55 is reduced, and accordingly, the axial length of the cylindrical roller 49 disposed between the inner and outer races 45, 47 can be increased to increase the load capacity of the bearing.
[0031]
In addition, the configuration of the inner and outer rings, the shield plate, the oil seal, the first lip portion for sealing, the second lip portion for sealing, the packing portion, the metal ring, and the like in the sealed rolling bearing of the present invention are the same as those of the above embodiment. It is needless to say that the present invention is not limited to this, and can take various forms based on the spirit of the present invention.
[0032]
For example, in the above embodiment, a double-row cylindrical roller bearing using a cylindrical roller as a rolling element has been described. However, the present invention can be applied to other types of sealed rolling bearings such as a four-row tapered roller bearing using a tapered roller. Of course.
Further, the application of the sealed rolling bearing of the present invention is not limited to outer ring roll bearings of rolling equipment such as a cluster mill, but is applied to various kinds of equipment in which a sealed rolling bearing having high sealing performance is required. Can be used.
[0033]
【The invention's effect】
As described above, according to the sealed rolling bearing of the present invention, the first sealing lip portion and the second sealing lip portion of the oil seal are simply locked to the seal mounting step of the outer ring. Since the elastic member is formed integrally on one metal ring, the number of components of the oil seal can be reduced, thereby reducing costs and improving the assemblability.
[0034]
Further, since the packing portion which is in pressure contact with the side surface of the step portion for mounting the seal is integrally formed on the metal ring, it is possible to improve the sealing performance between the side surface of the step portion for mounting the seal and the oil seal. it can.
Therefore, it is possible to prevent the lubricating oil from leaking between the side surface of the seal mounting step portion and the oil seal, thereby preventing the outside of the bearing from being stained by the leaking lubricating oil.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a main part of a sealed rolling bearing according to an embodiment of the present invention.
FIG. 2 is an enlarged view of a main part of the sealed rolling bearing shown in FIG.
FIG. 3 is a longitudinal sectional view of a main part of a conventional sealed rolling bearing.
FIG. 4 is an enlarged view of a main part of the sealed rolling bearing shown in FIG. 3;
[Explanation of symbols]
41 Sealed Rolling Bearing 45 Inner Ring 47 Outer Ring 48 Step 48b for Seal Installation Side Side 49 Cylindrical Roller 54 Shield Plate 54b Disk Part 54c Cylindrical Part 55 Oil Seal 61 First Lip Part 63 for Sealing Second Lip Part 65 for Seal 65 Packing 71 Metal ring 71a Outer flange

Claims (2)

A sealed rolling bearing in which the openings at both ends of the bearing are closed by a shield plate attached to the outer periphery of both ends of the inner ring and an oil seal attached to a seal mounting step on the inner periphery of both ends of the outer ring,
The oil seal is in pressure contact with a first sealing lip projecting radially inward, a second sealing lip projecting axially outward, and a side surface of the seal mounting step. And an elastic member having a packing portion, and is integrally formed on a single metal ring for locking the outer peripheral flange portion to the seal mounting step portion of the outer ring,
The shield plate extends radially outward so as to cover the openings at both ends of the bearing, and has an inner surface slidably in contact with the second sealing lip portion, and a bearing formed from the inner surface of the disk portion. A cylindrical portion protruding inward and having an outer peripheral surface slidingly in contact with the first sealing lip portion. The hermetic rolling bearing according to claim 1, wherein the first lip portion for sealing and the second lip portion for sealing are arranged so as to be arranged in a radial direction.

Images