JP2003269471A - Bearing device for railway vehicles - Google Patents

Abstract

(57) [Problem] To provide a good railway vehicle bearing device capable of preventing a falling off by increasing a fitting force of a sealing device to a bearing. SOLUTION: In the bearing device for a railway vehicle, a sealing device 45 provided at an axial end portion of a roller bearing is provided in a seal case 51 fitted on an inner peripheral surface of an end portion of an outer ring 43, and provided in the seal case 51. And an oil seal 33 to be used. A seal case fitting surface 47a is formed on the inner peripheral surface of the end of the outer race 43 so that the metal surface contacts the seal case 51. The seal case 51 is subjected to a grinding process to bring the metal surface into contact with the seal case fitting surface 47a, and an outer ring fitting surface which is tightly fitted to the seal case fitting surface 47a.
51a is formed.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing device for a railway vehicle, and more particularly to an improvement in a sealing device provided at an axial end of the bearing. 2. Description of the Related Art As a general railway vehicle bearing device,
For example, there is one shown in FIG. This kind of bearing device for railway vehicles has a double-row roller between a rear flinger (oil drainer) 23 fitted to the shoulder 1a of the axle 1 and a front flinger 21 fitted to the end of the axle 1. The bearing 3 is arranged. The roller bearing 3 includes two inner rings 11 and 12 divided in the axial direction of the axle 1, a single outer ring 14, and a plurality of rollers provided between the inner rings 11 and 12 and the outer ring 14. Rolling members (taper rollers) 15, cages 16 and 17 for holding the rolling members 15 between the inner and outer rings at intervals, and both end portions in the axial direction of the outer ring 14 so as to cover the gap between the inner and outer rings. The configuration includes a sealing device 28. When the shaft nut 24 screwed to the shaft end of the axle 1 is tightened, the inner rings 11 and 1 of the roller bearing 3 are tightened.
2 is fixed to the axle 1 by being sandwiched by the front flinger 21 and the rear flinger 23 from both sides in the axial direction. Further, at the end of the axle 1, a small lid 25 projecting a detent projection 25a on the inner periphery engages the detent projection 25a with a locking groove 1b provided at the end of the axle 1. It is mounted in a state. By connecting the small lid 25 and the shaft nut 24 via bolts 27 and integrating them, the shaft nut 24 is prevented from loosening. [0005] As shown in FIG. 7, the sealing device 28 has a stepped cylinder having one end fitted to the inner peripheral portion of the end of the outer ring 14 of the roller bearing 3 and the other end protruding from the end surface of the outer ring 14. And an oil seal (seal means) 33 having a seal lip fitted on the inner peripheral side of the seal case 31 and slidably in contact with the outer peripheral surface of the front flinger 21 or the rear flinger 23. This prevents foreign substances from entering the inside of the roller bearing 3 and leakage of lubricant (grease) from the inside of the bearing. [0006] The sealing device 28 must not come off or loosen from the outer ring 14 of the roller bearing 3 even if it is subjected to vibration or severe impact during rotation of the bearing. On the other hand, the roller bearing 3 has a sealing device
When the bearing is reused, it is necessary to restore the sealing function after installing the new sealing device 28. Therefore, as shown in FIG. 6, an annular seal case fitting surface 29a and a seal case fitting surface 29a are provided on the inner peripheral surface of the end of the outer race 14 into which one end of the seal case 31 is fitted. A seal case fitting portion 29 having an annular locking groove 29b formed in the inner side of 29a is formed. The seal case 31 is made of a thin steel plate, and has an annular outer ring fitting surface at one end fitted to the seal fitting portion 29 to be tightly fitted to the seal case fitting surface 29a. 31a, and a bead 31b which is formed to protrude at the tip of the outer ring fitting surface 31a and engages with the locking groove 29b.
And Incidentally, since the roller bearing 3 in the above-described rolling stock bearing device is equipped with the sealing device 28, the bearing box itself supporting the roller bearing 3 is provided with a bearing from external dust and rainwater. Often used without a protective sealing device. Accordingly, since the outer ring 14 of the roller bearing 3 and the seal case 31 of the sealing device 28 are exposed to the outside, it is inevitable that rainwater adheres or dew condensation occurs. Therefore, the outer ring 14 and the seal case 31 are subjected to a rust-preventive coating treatment to form a rust-preventive surface treatment coating 30 on the entire surface. [0010] However, in the above-described roller bearing 3 in the conventional railway vehicle bearing device, FIG.
As shown in the figure, the center of gravity G of the sealing device 28 is separated from the center position H of the fitting portion between the seal case fitting surface 29a and the seal case 31 by a distance L. Therefore,
When the vibration acceleration transmitted from the axle 1 acts on the roller bearing 3, the moment load generated due to the axial misalignment between the center of gravity G of the sealing device 28 and the seal case fitting surface 29 a causes the seal case fitting. As shown in FIG. 8, one end of the seal case 31 fitted to the seal fitting portion 29 may come off as a force to slide the surface 29a (the amount of disengagement: y in the figure). In addition, since the coating treatment for the outer ring 14 for the purpose of rust prevention treatment is generally performed by chemical treatment, a surface treatment coating 30 is applied to the entire surface of the outer ring 14. Therefore,
The seal case fitting surface 29a and the outer ring fitting surface 31a
It is also conceivable that the surface treatment film 30 is interposed between the seal case 31 and the friction coefficient, thereby making it easy for the seal case 31 to come off as described above. When such a detachment becomes large, the sealing device 28 falls off the roller bearing 3 and the roller bearing 3
It is impossible to prevent foreign matter from entering the inside of the bearing and leakage of grease from the inside of the bearing. SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems, and to provide a good railway vehicle bearing device capable of preventing the falling off by increasing the fitting force of the sealing device to the bearing. An object of the present invention is to provide a seal case in which a sealing device provided at an axial end of a bearing is fitted to an inner peripheral surface of an end of an outer ring, and the seal case. And a seal device provided in the bearing device for a railway vehicle, wherein an inner peripheral surface of an end portion of the outer ring has a seal case fitting surface which has been subjected to a grinding process to bring a metal surface into contact with the seal case. This is achieved by a railway vehicle bearing device characterized in that According to the above configuration, the metal surface of the seal case at the inner peripheral surface of the end portion of the outer ring is exposed by grinding, and the coefficient of friction of the seal case with the outer ring fit surface is increased. Can be. Therefore,
The fitting force of the seal case fitted to the inner peripheral surface at the end of the outer race can be improved. [0015] The seal case fitting surface is subjected to grinding so that a groove connected to a turning process when the seal fitting portion of the outer ring is turned is cut.
Therefore, it is possible to prevent the base oil of the grease filled in the bearing from flowing out of the bearing along the continuous groove of the turning process between the seal case and the outer ring fitting surface. That is, in order to prevent a decrease in the sealing performance of the seal case, a surface treatment film is left on the seal case fitting surface,
There is no need to fill the continuous groove of the turning process on the seal case fitting surface with the surface treatment film. Therefore,
When applying the surface treatment coating to the entire surface of the outer ring, masking is performed on the inner peripheral surface of the end of the outer ring in which the seal case fitting surface is ground, or grinding is performed on the seal case fitting surface in advance to form the outer ring. By removing the surface treatment film applied to the entire surface, the surface treatment film on the seal case fitting surface can be omitted. Therefore, even when the outer race has a surface treatment film, the metal case is exposed on the seal case fitting surface by grinding, so that the friction coefficient is prevented from being reduced by the surface treatment film. Also, regardless of the presence or absence of the surface treatment film, the seal case can be prevented from coming off. Preferably, an outer ring fitting surface which has been subjected to a grinding process to bring the metal surface into contact with the seal case fitting surface is also formed on the outer peripheral surface of the end portion of the seal case.
In this case, the seal case fitting surface and the outer ring fitting surface can increase the coefficient of static friction by direct contact between the grounds of the metal material, and the seal case fits on the inner peripheral surface at the end of the outer ring. The resultant force can be further improved. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a bearing device for a railway vehicle 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 railway vehicle bearing device according to a first embodiment of the present invention. However, the railway vehicle bearing device of the first embodiment is obtained by replacing the roller bearing 3 of the railway vehicle bearing device shown in FIG. 5 with a roller bearing 41 of the present embodiment. Since they are the same, the same reference numerals are given and detailed description is omitted. The roller bearing 41 according to the first embodiment includes an axle 1
And sealing devices 45 provided at both axial ends of the outer ring 43 so as to cover the gap between the two inner rings 11 and 12 divided in the axial direction and the single outer ring 43. The sealing device 45 is, as shown in FIG.
One end is fitted to the inner periphery of the end of the outer ring 43 and the other end projects from the end surface of the outer ring 43. Oil seal (seal means) having a seal lip that slides on the outer peripheral surface of the front flinger 21 or the rear flinger 23
33. Further, the other end 51 of the seal case 51
“c” protrudes into an annular groove 23 a formed on the facing surface of the rear lid 23, thereby forming a labyrinth seal with the rear lid 23. Therefore, the sealing device 45 prevents intrusion of foreign matter into the inside of the roller bearing 41 and leakage of lubricant (grease) from the inside of the bearing. As shown in FIG. 2, a seal case fitting surface 47a which has been subjected to a grinding process to bring the metal surface into contact with the seal case 51 is formed on the inner peripheral surface of the end of the outer race 43.
And a seal case fitting portion 4 having an annular locking groove 47b formed in the inner side of the seal case fitting surface 47a.
7 are configured. The seal case 51 is made of a thin steel plate. One end of the seal case 51 fitted to the seal fitting portion 47 is subjected to a grinding process to bring a metal surface into contact with the seal case fitting surface 47a. Together with the seal case fitting surface 47a.
An annular outer ring fitting surface 51a to be tightly fitted on the outer ring fitting surface 51a, and the locking groove 47
b. That is, after the outer ring 43 has its inner and outer peripheral surfaces processed to predetermined dimensions by turning, the outer ring 43 is subjected to grinding as described above to finish the dimensions of the seal case fitting surface 47a. Also, after the seal case 51 is processed to a predetermined size by press molding of a metal plate or the like, the outer ring fitting surface 51a is dimensionally finished by grinding. Next, after masking is applied to the inner peripheral surface of the end portion of the outer ring 43 and the outer ring fitting surface 51a of the seal case 51 so that the chemical does not adhere thereto, the entire surface is subjected to chemical treatment to prevent rust. A coating treatment is performed, and a surface treatment coating 30 for rust prevention is formed on all surfaces of the outer ring 43 and the seal case 51. Then, by removing the masking from the outer ring 43 and the seal case 51 on which the formation of the rust-preventive surface treatment film 30 has been completed, the seal case fitting surface 47a is formed.
In addition, the background of the metal material is exposed on the outer ring fitting surface 51a. Accordingly, in the roller bearing 41 according to the bearing device for a railway vehicle of the present embodiment, the seal case fitting surface 47a on the end inner peripheral surface of the outer ring 43 and the outer ring fitting surface 51a of the seal case 51 are ground. The processed metal background is exposed, and the coefficient of friction between the seal case fitting surface 47a and the outer ring fitting surface 51a can be increased. Therefore, the fitting force of the seal case 51 fitted to the inner peripheral surface at the end of the outer ring 43 can be improved, and the roller bearing 41 can tolerate a larger vibration acceleration. Can be planned. Further, by grinding the seal case fitting surface 47a, a groove connected to a turning process when the seal fitting portion 47 of the outer ring 43 is turned is cut. Therefore, it is possible to prevent the base oil of the grease filled in the bearing from flowing out of the bearing along the continuous groove of the turning process between the seal case 51 and the outer ring fitting surface 51a. That is, in order to prevent the sealing performance of the seal case 51 from deteriorating, the surface treatment film 30 is left on the seal case fitting surface 47a, and the turning process on the seal case fitting surface 47a is performed by the surface treatment film 30. There is no need to fill continuous grooves. Therefore, when the surface treatment film 30 is applied to the entire surface of the outer ring 43, the inner surface of the end portion of the outer ring 43 in which the seal case fitting surface 47a is ground is masked in advance so that the surface of the seal case fitting surface 47a is Treatment film 3
0 was not formed and the metal background was exposed. Therefore, even when the surface of the outer ring 43 is subjected to a coating treatment for rust prevention, the metal surface of the seal case fitting surface 47a is exposed by grinding, and the friction coefficient of the surface treatment coating 30 is increased. Is prevented, so that the outer ring 43 is less likely to slip out of the seal case 51 irrespective of the presence or absence of the surface treatment film 30. Further, the surface treatment film 30 for rust prevention is formed in advance by a chemical solution treatment on the entire surface of the outer ring 43 whose inner and outer peripheral surfaces have been machined to predetermined dimensions by turning, without using the above-described masking treatment. By grinding the outer race 43 to form the seal case fitting surface 47a,
The surface treatment film 30 on the seal case fitting surface 47a may be scraped off to expose the background of the metal material. The configuration of the bearing and the sealing device such as the seal case and the sealing means in the railway vehicle bearing device of the present invention is not limited to the configuration of the above embodiment.
It goes without saying that various forms can be adopted based on the spirit of the present invention. For example, the railcar bearing device according to the second embodiment of the present invention shown in FIG. 4 includes a rear flinger 67 fitted to the shoulder 1 a of the axle 1 and a front lid 68 attached to the end of the axle 1. Two rows of roller bearings 61 are arranged between them. The front lid 68 attached to the end of the axle 1
Are tightened with the tightening bolts 70, the roller bearing 61
Inner rings 11, 12 are fixed to the axle 1 by being sandwiched from both sides in the axial direction by a front lid 68 and a rear flinger 67 via spacers 65, 66, respectively. The tightening bolt 70
Is prevented from being loosened by a tongue detent washer 71. The sealing device 75 for the roller bearing 61 has a stepped cylindrical seal case 7 having one end fitted to the inner peripheral portion of the end of the outer ring 43 and the other end protruding from the end surface of the outer ring 43.
6 and an oil seal 33 having a seal lip fitted on the inner peripheral side of the seal case 76 and slidably in contact with the outer peripheral surfaces of the spacers 65 and 66, respectively. The sealing device 7
5, the inner peripheral surface of the end of the outer race 43 and the seal case 76
The sealing device 45 of the first embodiment is provided on the outer peripheral surface at one end.
Similarly to the above, a seal case fitting surface and an outer ring fitting surface which have been subjected to a grinding process to bring the metal surfaces into contact with each other are provided. Therefore, the fitting force of the seal case 76 fitted to the inner peripheral surface of the end of the outer ring 43 can be improved, and the roller bearing 61 can allow a larger vibration acceleration. Therefore, the bearing device for a railway vehicle according to the second embodiment can improve the reliability of the bearing similarly to the bearing device for a railway vehicle according to the first embodiment. Further, for example, in each of the above embodiments,
As an example, double-row tapered roller bearings have been described.
It goes without saying that the present invention is applicable to other bearings such as cylindrical roller bearings. Also, the sealing means of the present invention is not limited to the oil seal 33 in the above embodiment, and other sealing means can be used. According to the bearing device for a railway vehicle of the present invention described in detail above, the seal case fitting surface on the inner peripheral surface of the end portion of the outer ring is in a state where the metal background is exposed by grinding. Thus, the friction coefficient of the seal case with respect to the outer ring fitting surface can be increased. Therefore, the fitting force of the seal case fitted to the inner peripheral surface at the end of the outer ring can be improved, and the bearing can tolerate a larger vibration acceleration, so that the reliability can be improved. The seal case fitting surface is subjected to grinding so that a groove connected to the turning process when the seal fitting portion of the outer ring is turned is cut.
Therefore, it is possible to prevent the base oil of the grease filled in the bearing from flowing out of the bearing along the continuous groove of the turning process between the seal case and the outer ring fitting surface. That is, in order to prevent the sealing performance of the seal case from deteriorating, a surface treatment film is left on the seal case fitting surface,
There is no need to fill the continuous groove of the turning process on the seal case fitting surface with the surface treatment film. Therefore,
When applying the surface treatment coating to the entire surface of the outer ring, masking is performed on the inner peripheral surface of the end of the outer ring in which the seal case fitting surface is ground, or grinding is performed on the seal case fitting surface in advance to form the outer ring. By removing the surface treatment film applied to the entire surface, the surface treatment film on the seal case fitting surface can be omitted. Therefore, even when the outer ring has a surface treatment film, the metal case is exposed on the seal case fitting surface by grinding so that the friction coefficient is prevented from being reduced by the surface treatment film. Also, regardless of the presence or absence of the surface treatment film, the seal case can be prevented from coming off.
Therefore, it is possible to provide a good railcar bearing device that can prevent the falling off by increasing the fitting force of the sealing device to the bearing.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view of a railway vehicle bearing device according to a first embodiment of the present invention. FIG. 2 is an enlarged longitudinal sectional view of the sealing device shown in FIG. 1 before assembly. FIG. 3 is an enlarged longitudinal sectional view of an assembled state of the sealing device shown in FIG. 2; FIG. 4 is a longitudinal sectional view of a railway vehicle bearing device according to a second embodiment of the present invention. FIG. 5 is a longitudinal sectional view of a conventional railcar bearing device. FIG. 6 is an enlarged vertical sectional view of the sealing device shown in FIG. 5 before assembly. FIG. 7 is an enlarged longitudinal sectional view of an assembled state of the sealing device shown in FIG. 6; 8 is an enlarged vertical sectional view for explaining a problem in the conventional sealing device shown in FIG. [Description of Signs] 1 Axle 30 Surface treatment coating 33 Oil seal (seal means) 41 Roller bearing (bearing) 43 Outer ring 45 Sealing device 47 Seal case fitting portion 47a Seal case fitting surface 47b Lock groove 51 Seal case 51a Outer ring Fitting surface 51b Bead

   ────────────────────────────────────────────────── ─── Continuation of front page    F term (reference) 3J016 AA04 BB03 BB16 CA03                 3J101 AA16 AA25 AA32 AA43 AA54                       AA62 BA54 BA57 BA73 DA11                       DA16 FA04 FA44 GA02

Claims (1)

Claims 1. A sealing device provided at an axial end of a bearing includes a seal case fitted to an inner peripheral surface of an end of an outer ring, and sealing means provided in the seal case. A bearing device for a railway vehicle, comprising: a seal case fitting surface which has been subjected to a grinding process in order to bring a metal surface into contact with the seal case, on an inner peripheral surface of an end portion of the outer ring. Bearing device for railway vehicles.