Railway vehicle gear units

Abstract

The present invention provides a gear device for railway vehicles. A small gear and a large gear (5) are accommodated in a gear box (1) in a state of being meshed with each other in a horizontal direction, wherein the small gear is fixed to an input shaft and the large gear is fixed to an axle (4), bearings for the input shaft and bearings for the axle (7) are installed on the side walls (11) on both axial sides of the gear box (1), a case cover (8) is provided to cover an opening (15) formed on the upper surface of the gear box (1), and an annular plate (52) protruding radially outward from the boss (51) is fixed to both axial ends of a boss (51) of the large gear externally embedded in the axle (4). The following situation can be suppressed: the movement component toward one side of the axial direction applied to the lubricating oil flying up by the large gear (5) causes the lubricating oil to flow from the case cover to the side wall (11) on one side of the axial direction, thereby a large amount of lubricating oil flows into the axle bearing (7).

Description

Technical Field

[0001] The present invention relates to a railway vehicle gear device as described below, that is, the railway vehicle gear device is configured as follows: it is provided with a gear box, in which a small gear and a large gear are housed in a state of being meshed with each other in a horizontal direction, wherein the small gear is fixed to an input shaft that is rotationally driven by a driving source, and the large gear is fixed to an axle, and bearings for the input shaft and bearings for the axle are installed on the side walls on both axial sides of the gear box. Background Art

[0002] As is well known, in the past, as a gear device for railway vehicles of this type, a gear box is formed with an opening on the upper surface through which a large gear can be inserted from above, and a box cover for covering the opening is installed on the upper surface of the gear box (for example, refer to Patent Document 1). In this gear device, the gear box has an opening on the upper surface through which a large gear can be inserted from above, and a box cover for covering the opening is installed on the upper surface of the gear box. The box cover is formed in a shape that is recessed upward so as to be able to accommodate the upper part of the large gear protruding upward from the opening on the upper surface of the gear box. In addition, according to the gear device for railway vehicles, the large gear can be used to make the lubricating oil retained in the lower part of the gear box fly up, thereby supplying the lubricating oil to various lubrication parts including the part where the small gear meshes with the large gear.

[0003] However, due to the distortion of the tooth direction of the large gear formed by the helical gear, the movement component toward one side of the axial direction is added to the lubricating oil flying up by the large gear. As a result, the lubricating oil is biased toward one side of the axial direction in the case cover, and a large amount of lubricating oil flows to the side wall portion of the gear case on one side of the axial direction and flows into the axle bearing on one side of the axial direction. In addition, once the rotation speed of the large gear exceeds the specified speed, the lubricating oil flying up by the large gear is biased toward the other side of the axial direction in the case cover, and a large amount of lubricating oil flows to the side wall portion of the gear case on the other side of the axial direction and flows into the axle bearing on the other side of the axial direction, although the reason cannot be determined.

[0004] Here, a labyrinth seal is provided on the axial outer side of the axle bearing to prevent the lubricating oil supplied to the bearing from leaking to the outside. However, once a large amount of lubricating oil flows into the bearing as described above, the lubricating oil leakage cannot be prevented by the labyrinth seal alone. Therefore, in the past, in addition to the labyrinth seal provided on the axial outer side of the axle bearing, a rubber oil seal was also provided. However, the oil seal is a consumable part and needs to be replaced, which leads to the problem that maintenance becomes cumbersome.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Utility Model Publication No. 64-46572 Summary of the invention

[0008] In view of the above-mentioned problems, the present invention aims to provide a railway vehicle gear device as described below, which can suppress a large amount of lubricating oil from flowing into the axle bearings, and prevent the lubricating oil supplied to the axle bearings from leaking to the outside even if an oil seal is not provided or the replacement frequency of the oil seal is reduced.

[0009] In order to solve the above-mentioned problems, the gear device for railway vehicles of the present invention is constructed as follows, which includes a gear box, in which a small gear and a large gear are housed in a state of meshing with each other in a horizontal direction, wherein the small gear is fixed to an input shaft that is rotationally driven by a driving source, and the large gear is fixed to an axle, and bearings for the input shaft and bearings for the axle are installed on the side walls on both axial sides of the gear box, the gear box has an opening on the upper surface through which the large gear can be inserted from above, and a case cover for covering the opening is installed on the upper surface of the gear box, the case cover is formed in a shape that is recessed upward so as to be able to accommodate: the upper part of the large gear protruding upward from the opening on the upper surface of the gear box, and is characterized in that: an annular plate protruding radially outward from the boss portion is fixed to the axial ends of the boss portion of the large gear embedded on the axle.

[0010] According to the present invention, near the configuration portion of the axle bearing, airflow toward the radial outside is generated by the rotation of the annular plate. As a result, even if a large amount of lubricating oil flows from the inside of the case cover to the side wall portion of the gear case and flows into the vicinity of the configuration portion of the axle bearing, the lubricating oil can be pushed back by the airflow generated as described above, thereby preventing a large amount of lubricating oil from flowing into the axle bearing. Therefore, even if an oil seal is not provided or the replacement frequency of the oil seal is reduced, the lubricating oil supplied to the axle bearing can be prevented from leaking to the outside, thereby improving the maintainability. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a cutaway side view of the railway vehicle gear device according to the embodiment of the present invention.

[0012] Figure 2 It is along Figure 1 Cross-sectional view after cutting along line Ⅱ-Ⅱ.

[0013] Figure 3 It is along Figure 1 The cross-sectional view after cutting through III-III.

[0014] Description of Reference Numerals

[0015] 1…gear box; 11…side wall portion; 15…opening of the upper surface; 2…input shaft; 3…small gear; 4…axle; 5…large gear; 51…boss portion; 52…annular plate; 6…bearing for input shaft; 7…bearing for axle; 8…box cover. DETAILED DESCRIPTION

[0016] Reference Figure 1 The railway vehicle gear device of the embodiment of the present invention includes a gear box 1. In the gear box 1, a pinion 3 and a gear 5 are accommodated in a state of being meshed with each other in the horizontal direction, wherein the pinion 3 is composed of a helical gear and is fixed to an input shaft 2 ( Figure 3 The large gear 5 is composed of a helical gear and is fixed to the axle 4. Figure 2 , Figure 3 , a pair of input shaft bearings 6, 6 for axially supporting the input shaft 2 and a pair of axle bearings 7, 7 for axially supporting the axle 4 are mounted on the side wall portions 11, 11 on both axial sides of the gear case 1. Specifically, an opening 111 which is concentric with the input shaft 2 and has a diameter larger than that of the pinion gear 3, and an opening 112 which is concentric with the axle 4 and has a diameter smaller than that of the gear 5 are formed on each side wall portion 11. Moreover, a bearing box 61 which has the input shaft bearing 6 built therein is mounted on each side wall portion 11 in such a manner as to block the opening 111, and a bearing box 71 which has the axle bearing 7 built therein is mounted on each side wall portion 11 in such a manner as to block the opening 112. The pinion gear 3 is integrally formed with the input shaft 2, and is inserted into the gear case 1 through the opening 111 of the side wall portion 11 on one axial side. Alternatively, the pinion gear 3 which is separate from the input shaft 2 may be externally fitted and fixed to the input shaft 2.

[0017] A first oil reservoir 12 is provided at the lower portion of the gear box 1 so that the lower portion of the large gear 5 can be immersed. 1 , the second oil reservoir 12 located below the pinion 3 2 , and the first oil storage portion 12 1 and the second oil storage portion 12 2 The partition wall 13 is formed with: 1 The second oil storage portion 12 2 The oil is stored in the first oil storage portion 12 1 The lubricating oil is stirred up by the rotation of the large gear 5, and the stirred up lubricating oil is supplied to various lubricating parts such as the meshing part between the small gear 3 and the large gear 5, and the bearings 6 and 7 for the input shaft and the axle. 1The bottom surface of the gear box 1 is formed with an opening, and a plug body 14 is installed in the opening. A drain plug 141 is installed in the plug body 14, and the lubricating oil in the gear box 1 can be discharged to the outside by pulling out the drain plug 141.

[0018] In addition, the gear box 1 has an opening 15 on the upper surface into which the large gear 5 can be inserted from above. Moreover, a cover 8 for covering the opening 15 is installed on the upper surface of the gear box 1. The cover 8 is formed in a shape that is concave upward so as to be able to receive the upper part of the large gear 5 protruding upward from the opening 15 on the upper surface of the gear box 1.

[0019] However, the following situation may occur, that is, as described in the background technology section, the lubricating oil flying up by the large gear 5 will deviate to the axial side in the case cover 8 due to the motion component applied to the lubricating oil in the axial direction, and a large amount of lubricating oil will flow to the side wall portion 11 on the axial side of the gear case 1 and flow into the axle bearing 7 on the axial side. Here, a cover 72 is installed at the axial outer end of the bearing box 71 in which the axle bearing 7 is built. In addition, a plurality of labyrinth seals 73 are provided in the bearing box 71 and the cover 72 to prevent the lubricating oil supplied to the axle bearing 7 from leaking to the outside. However, once a large amount of lubricating oil flows into the axle bearing 7, the labyrinth seal 73 alone cannot prevent the lubricating oil from leaking to the outside, and a rubber oil seal needs to be provided.

[0020] Therefore, in the present embodiment, annular plates 52, 52 protruding radially outward from the boss portion 51 are fixed to both axial ends of the boss portion 51 of the large gear 5 externally fitted to the axle 4. Accordingly, near the arrangement portion of each axle bearing 7, airflow toward the radial outward is generated by the rotation of each annular plate 52. Thus, even if a large amount of lubricating oil flows into the vicinity of the arrangement portion of the axle bearing 7 on one side in the axial direction due to the axial deviation of the lubricating oil at the case cover 8, the lubricating oil can be pushed back by the airflow generated as described above, thereby preventing a large amount of lubricating oil from flowing into the axle bearing 7 on one side in the axial direction. Therefore, even if an oil seal is not provided, the lubricating oil of the axle bearing 7 can be prevented from leaking to the outside, and as a result, there is no need to replace the oil seal, thereby improving the maintainability. Furthermore, even when the oil seal is provided outside the axle bearing 7, even if the oil seal is considerably deteriorated, the lubricating oil will not leak to the outside, so that the replacement frequency of the oil seal can be reduced, thereby improving the maintainability.

[0021] Although the embodiments of the present invention have been described above with reference to the drawings, the present invention is not limited thereto, and various modifications can be made without departing from the spirit of the present invention.

Claims

1. A railway vehicle gear device, comprising a gear box, wherein a small gear and a large gear are housed in the gear box in a state of being meshed with each other in a horizontal direction, wherein: The small gear is fixed to an input shaft that is rotationally driven by a driving source, and the large gear is fixed to an axle. Bearings for the input shaft and bearings for the axle are installed on the side walls on both axial sides of the gear box. The gear box has an opening on the upper surface through which the large gear can be inserted from above, and a box cover for covering the opening is installed on the upper surface of the gear box, and the box cover is formed in a shape concave upward so as to receive: the upper part of the large gear protruding upward from the opening on the upper surface of the gear box, and lubricating oil is stored in the gear box, characterized in that: An annular plate protruding radially outward from the boss is fixed to both axial ends of the boss of the large gear fitted on the outside of the axle. The airflow toward the radial outside generated by the rotation of the annular plate suppresses the lubricating oil lifted by the large gear from flowing into the bearing for the axle.

Images