Bearing device and conical bearing

Abstract

To provide an art which enables further improvement of lubricity between a large diameter end surface of a conical roller and a large flange part.SOLUTION: A bearing device 1 includes: an inner member 2; an annular outer member 4 concentrically arranged with the inner member 2; a plurality of conical rollers 6 disposed between the inner member 2 and the outer member 4; and a retainer 8 which is provided between the inner member 2 and the outer member 4 and holds the conical rollers 6. The retainer 8 has a large diameter annular part 32 disposed at the side of the large diameter end surface 6b of the conical rollers 6. The inner member 2 has: an axial hole 11 which penetrates through the inner member 2 in an axial direction; a large flange part 18 which slidably contacts with the large diameter end surfaces 6b of the conical rollers 6; and through holes 22 each of which penetrates through an outer peripheral surface 20 connected to the large flange part 18 and the axial hole 11. The position in the axial direction of the opening 22a of the through hole 22 on the outer peripheral surface 20 is located close to the side of the conical rollers 6 relative to the axial tip 32a of the large diameter annular part 32.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a bearing device and a tapered roller bearing.

Background Art

[0002] Patent Document 1 discloses a technique for enhancing the lubricity inside a bearing by providing an oil groove in an annular portion on the large-diameter side of a cage.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above conventional example, the lubricating oil held in the oil groove tends to flow radially outward due to centrifugal force. For this reason, there is a possibility that the lubricity between the large flange portion of the inner ring, which is radially inward of the oil groove, and the large-diameter end face of the tapered roller may deteriorate. Such a tendency is particularly prominent when the amount of lubricating oil supplied is small.

[0005] Therefore, a measure for further enhancing the lubricity between the large-diameter end face of the tapered roller and the flange portion is desired.

Means for Solving the Problems

[0006] The bearing device according to the embodiment includes an inner member, an annular outer member concentrically arranged with the inner member, a plurality of tapered rollers interposed between the inner member and the outer member, and a cage provided between the inner member and the outer member for holding the plurality of tapered rollers. The cage has an annular portion disposed on the large-diameter end face side of the plurality of tapered rollers. The inner member has an axial hole penetrating the inner member in the axial direction, a large flange portion in sliding contact with the large-diameter end faces of the plurality of tapered rollers, and a through hole penetrating an outer peripheral surface connected to the large flange portion and the axial hole. The axial position of the opening of the through hole on the outer peripheral surface is on the side of the plurality of tapered rollers rather than the axially leading end portion of the annular portion.

Advantages of the Invention

[0007] According to the present disclosure, the lubricity between the large-diameter end face of the tapered roller and the large flange portion can be further enhanced.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0009] First, the contents of the embodiment will be listed and described. [Summary of the Embodiment] (1) In the bearing device according to the embodiment, there are an inner member, an annular outer member concentrically arranged with the inner member, a plurality of tapered rollers interposed between the inner member and the outer member, and a cage provided between the inner member and the outer member for holding the plurality of tapered rollers. The cage has an annular portion arranged on the large-diameter end face side of the plurality of tapered rollers. The inner member has an axial hole penetrating the inner member in the axial direction, a large flange portion in sliding contact with the large-diameter end faces of the plurality of tapered rollers, and a through hole penetrating the outer peripheral surface connected to the large flange portion and the axial hole. The axial position of the opening of the through hole on the outer peripheral surface is on the side of the plurality of tapered rollers rather than the axial tip of the annular portion.

[0010] According to the above configuration, for example, the lubricating oil supplied to the bearing device enters the axial hole of the inner member. Further, the lubricating oil enters from the axial hole into the through hole by the centrifugal force generated when the bearing device rotates, and is supplied from the opening to the vicinity of the large flange portion. At this time, since the axial position of the opening is on the side of the plurality of tapered rollers rather than the axial tip of the large-diameter annular portion of the cage, the lubricating oil released from the opening on the outer peripheral surface hits the inner peripheral surface of the large-diameter annular portion, and the scattering to the surroundings is suppressed. Therefore, the lubricating oil from the opening is effectively supplied to the vicinity of the large flange portion. As a result, even when the amount of lubricating oil supplied is small, the lubricity between the large-diameter end face of the tapered roller and the large flange portion can be further enhanced.

[0011] (2) In the above bearing device, the annular portion may have an annular protrusion protruding radially inward from the axial tip of the annular portion. In this case, it is possible to suppress the lubricating oil hitting the inner peripheral surface of the annular portion from flowing to the opposite side of the tapered roller, and the supply of the lubricating oil to the vicinity of the large flange portion can be performed more effectively.

[0012] (3) In the above bearing device, the inner peripheral surface of the annular portion may include an inclined surface that gradually expands in diameter from the axial tip side of the annular portion toward the side of the plurality of tapered rollers. Also in this case, it is possible to suppress the lubricating oil hitting the inner peripheral surface of the annular portion from flowing to the opposite side of the tapered roller, and it is possible to more effectively supply the lubricating oil to the vicinity of the large flange portion.

[0013] (4) Further, in the bearing device, when the outer peripheral surface has an annular stepped portion protruding radially outward, the stepped portion may be provided between the opening of the through hole and the axial tip of the annular portion in the axial direction. In this case, it is possible to suppress the lubricating oil from the opening from flowing along the outer peripheral surface to the opposite side of the tapered roller, and it is possible to more effectively supply the lubricating oil to the vicinity of the large flange portion.

[0014] (5) In the bearing device, the inner member may have a shaft-shaped main body portion and a gear portion centered on the axis of the main body portion. In this case, the bearing device can rotatably support the gear portion.

[0015] (6) Further, an embodiment viewed from another aspect is a tapered roller bearing. This tapered roller bearing includes an inner ring, an outer ring concentrically arranged with the inner ring, a plurality of tapered rollers interposed between the inner ring and the outer ring, and a cage provided between the inner ring and the outer ring for holding the plurality of tapered rollers. The cage has an annular portion arranged on the large-diameter end face side of the plurality of tapered rollers. The inner ring has a large flange portion in sliding contact with the large-diameter end faces of the plurality of tapered rollers, and a through hole penetrating the outer peripheral surface connected to the large flange portion and the inner peripheral surface of the inner ring. The axial position of the opening of the through hole on the outer peripheral surface is on the side of the plurality of tapered rollers rather than the axial tip of the annular portion.

[0016] According to the above configuration, if lubricating oil is supplied from the through hole, the lubricating oil is effectively supplied from the opening to the vicinity of the large flange portion. As a result, even when the amount of lubricating oil supplied is small, the lubricity between the large-diameter end face of the tapered roller and the large flange portion can be further improved.

[0017] [Details of the Embodiment] Hereinafter, preferred embodiments will be described with reference to the drawings. Note that at least a part of each of the embodiments described below may be arbitrarily combined.

[0018] 〔Regarding the First Embodiment〕 FIG. 1 is a cross-sectional view showing an example of a bearing device according to the first embodiment. In FIG. 1, the bearing device 1 includes an inner member 2, a pair of outer members 4, a plurality of tapered rollers 6, and a pair of cages 8.

[0019] The inner member 2 is a member formed using machine structural steel or the like. The inner member 2 has a shaft portion 10 (main body portion) and a gear portion 13. The shaft portion 10 and the gear portion 13 are integrally formed. The gear portion 13 is provided substantially at the center in the axial direction of the shaft portion 10. The gear portion 13 is provided so as to protrude from the circumferential surface 10a of the shaft portion 10. The gear portion 13 has a tooth portion 13a centered on the axis of the shaft portion 10. The gear portion 13 functions as a gear by rotating about the axis of the shaft portion 10. The shaft portion 10 has an axial hole 11. The axial hole 11 penetrates both end faces 10b of the shaft portion 10 along the axis of the shaft portion 10.

[0020] The pair of outer members 4 are annular members formed using machine structural steel or the like. The pair of outer members 4 are provided at both axial ends of the shaft portion 10. The plurality of tapered rollers 6 are members formed using bearing steel, machine structural steel, or the like. The plurality of tapered rollers 6 are interposed between the pair of outer members 4 and the shaft portion 10. Also, the pair of cages 8 circumferentially hold the plurality of tapered rollers 6 arranged at both axial ends of the shaft portion 10. That is, the pair of outer members 4, the plurality of tapered rollers 6, and the pair of cages 8 constitute a pair of tapered roller bearings with the inner member 2. The pair of outer members 4 are fixed rings fixed to a housing that houses the bearing device 1. Therefore, the inner member 2 is rotatably supported with respect to the housing.

[0021] Figure 2 is an enlarged cross-sectional view of one end of the bearing device 1. The configurations of both ends of the bearing device 1 are the same. Therefore, only one end of the bearing device 1 will be described here.

[0022] In Figure 2, the inner peripheral surface 4a of the outer member 4 has an outer raceway surface 12. The outer raceway surface 12 has a tapered shape that gradually increases in diameter from the end face 10b side of the shaft portion 10 toward the gear portion 13 side. Also, the circumferential surface 10a of the shaft portion 10 has an inner raceway surface 14. The inner raceway surface 14 has a tapered shape that gradually increases in diameter from the end face 10b side toward the gear portion 13 side. The outer raceway surface 12 and the inner raceway surface 14 face each other. A plurality of tapered rollers 6 are rotatably interposed between the outer raceway surface 12 and the inner raceway surface 14.

[0023] The cage 8 is a member formed of resin, metal, or the like. The cage 8 has a small-diameter annular portion 30, a large-diameter annular portion 32, and a plurality of column portions 34. The small-diameter annular portion 30 is disposed on the small-diameter end face 6a side of the tapered roller 6. The large-diameter annular portion 32 is disposed on the large-diameter end face 6b side of the tapered roller 6. The small-diameter annular portion 30 and the large-diameter annular portion 32 are spaced apart in the axial direction and are connected by a plurality of column portions 34.

[0024] An oil groove 30g is provided in the small-diameter annular portion 30. Also, an oil groove 32g is provided in the large-diameter annular portion 32. These oil grooves 30g and 32g have the function of holding lubricating oil. By the oil grooves 30g and 32g holding the lubricating oil, the lubricity inside the bearing can be enhanced.

[0025] The cage 8 has a plurality of pockets. A pocket is a space surrounded by a pair of adjacent column portions 34, the small-diameter annular portion 30, and the large-diameter annular portion 32. The plurality of pockets are provided at equal intervals in the circumferential direction. The tapered rollers 6 are held in these plurality of pockets.

[0026] The shaft peripheral surface 10a of the shaft portion 10 has, in addition to the inner raceway surface 14, a small flange portion 16 and a large flange portion 18. The small flange portion 16 is provided on the axial end surface 10b side of the inner raceway surface 14. The small flange portion 16 is in sliding contact with the small-diameter end surface 6a of the tapered roller 6. The large flange portion 18 is provided on the axial gear portion 13 side of the inner raceway surface 14. The large flange portion 18 is in sliding contact with the large-diameter end surface 6b of the tapered roller 6. The large flange portion 18 is connected to the outer peripheral surface 20 of the shaft peripheral surface 10a.

[0027] Also, the shaft portion 10 has a plurality of through holes 22. The plurality of through holes 22 penetrate the outer peripheral surface 20 and the axial hole 11. The plurality of through holes 22 extend radially along the radial direction. The plurality of through holes 22 are arranged at equal intervals in the circumferential direction. The plurality of through holes 22 are provided adjacent to the large flange portion 18. More specifically, the axial position of the opening 22a of the plurality of through holes 22 is on the side of the plurality of tapered rollers 6 rather than the axial tip portion 32a of the large-diameter annular portion 32 of the cage 8.

[0028] According to the above configuration, for example, the lubricating oil in the housing in which the bearing device 1 is accommodated enters the axial hole 11 of the shaft portion 10. Further, the lubricating oil enters from the axial hole 11 into the through hole 22 by the centrifugal force generated when the bearing device 1 rotates, and is discharged from the opening 22a and supplied to the vicinity of the large flange portion 18. At this time, since the axial position of the opening 22a is on the side of the plurality of tapered rollers 6 rather than the axial tip portion 32a of the large-diameter annular portion 32 of the cage 8, the lubricating oil discharged from the opening 22a on the outer peripheral surface 20 hits the inner peripheral surface 32b of the large-diameter annular portion 32, and the scattering to the surroundings is suppressed. Therefore, the lubricating oil from the opening 22a is effectively supplied to the vicinity of the large flange portion 18. As a result, even when the amount of lubricating oil supplied is small, the lubricity between the large-diameter end surface 6b of the tapered roller 6 and the large flange portion 18 can be further enhanced.

[0029] Also, in the present embodiment, the large-diameter annular portion 32 of the cage 8 has an annular protrusion 33. The annular protrusion 33 protrudes radially inward from the axial front end portion 32a of the large-diameter annular portion 32. The annular protrusion 33 protrudes radially inward with respect to the inner peripheral surface 32b. Since the large-diameter annular portion 32 has the annular protrusion 33, it is possible to suppress the lubricating oil hitting the inner peripheral surface 32b from flowing to the opposite side (outside the bearing) of the spherical roller 6, and it is possible to more effectively supply the lubricating oil to the vicinity of the large flange portion 18.

[0030] FIG. 3 is a cross-sectional view of a main part of the bearing device 1 according to a modified example of the first embodiment. This modified example is different from the above embodiment in that the inner peripheral surface 32b of the large-diameter annular portion 32 of the cage 8 has an inclined surface, and a stepped portion 20c is provided on the outer peripheral surface 20 of the axial peripheral surface 10a.

[0031] The inner peripheral surface 32b of the cage 8 of the present embodiment includes an inclined surface that gradually increases in diameter from the axial front end portion 32a side of the large-diameter annular portion 32 toward the spherical roller 6 side. Thereby, the inner peripheral surface 32b and the annular protrusion 33 are smoothly connected. Since the inner peripheral surface 32b has the inclined surface, it is possible to suppress the lubricating oil hitting the inner peripheral surface 32b from flowing to the opposite side of the spherical roller 6, and it is possible to more effectively supply the lubricating oil to the vicinity of the large flange portion 18.

[0032] Also, as shown in FIG. 3, the outer peripheral surface 20 of the present embodiment has a first peripheral surface 20a, a second peripheral surface 20b, and a stepped portion 20c. The first peripheral surface 20a is a peripheral surface connected to the large flange portion 18. The second peripheral surface 20b is a peripheral surface arranged on the axial gear portion 13 side (opposite side of the spherical roller 6) of the first peripheral surface 20a. The stepped portion 20c is an annular step connecting the first peripheral surface 20a and the second peripheral surface 20b.

[0033] The stepped portion 20c is provided between the opening 22a of the through hole 22 and the axial front end portion 32a of the large-diameter annular portion 32 in the axial direction. Therefore, it is possible to suppress the lubricating oil from flowing from the opening 22a along the outer peripheral surface 20 to the opposite side of the tapered roller 6, and it is possible to more effectively supply the lubricating oil to the vicinity of the large flange portion 18. Further, in the present embodiment, the stepped portion 20c is provided along the edge of the opening 22a. Thereby, it is possible to suppress the lubricating oil discharged from the opening 22a from scattering to the opposite side of the tapered roller 6, and it is possible to more effectively supply the lubricating oil to the vicinity of the large flange portion 18.

[0034] 〔Regarding the second embodiment〕 FIG. 4 is a cross-sectional view showing an example of a tapered roller bearing according to the second embodiment. The tapered roller bearing 100 of the present embodiment includes an inner ring 102, an outer ring 104, a plurality of tapered rollers 106, and a cage 108.

[0035] The outer ring 104 has an outer raceway surface 112. The inner ring 102 has an inner raceway surface 114. The outer raceway surface 112 and the inner raceway surface 114 face each other. The plurality of tapered rollers 106 are interposed between the outer raceway surface 112 and the inner raceway surface 114 so as to be freely rotatable. The cage 108 has a small-diameter annular portion 130, a large-diameter annular portion 132, and a plurality of column portions 134.

[0036] The tapered roller bearing 100 of the present embodiment has the same configuration as the tapered roller bearing composed of the outer member 4, the inner member 2, the plurality of tapered rollers 6, and the cage 8 included in the bearing device 1 shown in the first embodiment.

[0037] The large-diameter annular portion 132 of the cage 108 has an annular protrusion 133. The annular protrusion 133 protrudes radially inward from the axially front end portion 132a of the large-diameter annular portion 132. The annular protrusion 133 protrudes radially inward with respect to the inner peripheral surface 132b.

[0038] The inner ring 102 has a large flange portion 118 that is in sliding contact with the large-diameter end surface 106b of the tapered roller 106. The large flange portion 118 is connected to the outer peripheral surface 120 on the large-diameter side of the inner ring 102. Also, the inner ring 102 has a plurality of through holes 122. The plurality of through holes 122 penetrate through the outer peripheral surface 120 and the inner peripheral surface 102a of the inner ring 102. The plurality of through holes 122 extend radially along the radial direction. The plurality of through holes 122 are arranged at equal intervals in the circumferential direction. The axial position of the opening 122a of the plurality of through holes 122 is on the side of the plurality of tapered rollers 106 rather than the axial tip portion 132a of the large-diameter annular portion 132 of the cage 108.

[0039] The tapered roller bearing 100 of the present embodiment is externally fitted to the outer peripheral surface 200a of the rotating shaft 200. The rotating shaft 200 has an axial hole 201 that penetrates the rotating shaft 200 in the axial direction and a plurality of through holes 202. The plurality of through holes 202 penetrate through the outer peripheral surface 200a of the rotating shaft 200 and the axial hole 201. The plurality of through holes 202 extend radially along the radial direction. The plurality of through holes 202 are arranged at equal intervals in the circumferential direction. The openings 202a of the plurality of through holes 202 coincide with the openings 122b of the through holes 122 on the inner peripheral surface 102a of the inner ring 102.

[0040] Thus, when lubricating oil is supplied to the axial hole 201 of the rotating shaft 200, the lubricating oil enters from the axial hole 201 into the through holes 202 due to the centrifugal force generated by the rotation of the rotating shaft 200 and the inner ring 102, further passes through the through holes 122, and is supplied from the opening 122a of the outer peripheral surface 120 to the vicinity of the large flange portion 118. As a result, similar to the first embodiment, also in the present embodiment, the lubricating oil from the opening 122a is effectively supplied to the vicinity of the large flange portion 118. As a result, even when the amount of lubricating oil supplied is small, the lubricity between the large-diameter end surface 106b of the tapered roller 106 and the large flange portion 118 can be further improved.

[0041] 〔Others〕 The embodiments disclosed this time are illustrative in all respects and not restrictive. For example, although the case where a plurality of through holes 22 (through holes 122) provided in the shaft portion 10 of the inner member 2 is illustrated, at least one through hole 22 may be provided. Further, the number of the through holes 22 can be appropriately set according to the diameter of the shaft portion 10 and the diameter of the through hole 22.

[0042] The scope of the rights of the present invention is not limited to the above-described embodiments, and includes all modifications within the scope equivalent to the configurations described in the claims.

Explanation of reference numerals

[0043] 1 Bearing device 2 Inner member 4 Outer member 4a Inner peripheral surface 6 Tapered roller 6b Large-diameter end face 8 Cage 11 Axial hole 13 Gear portion 18 Large flange portion 20 Outer peripheral surface 20c Step portion 22 Through hole 22a Opening 32a Axial tip 32b Inner peripheral surface 33 Annular projection 100 Tapered roller bearing 102 Inner ring 102a Inner peripheral surface 104 Outer ring 106b Large-diameter end face 108 Cage 118 Large flange portion 120 Outer peripheral surface 122 Through hole 122a Opening 132a Axial tip 132b Inner peripheral surface 133 Annular projection

Claims

1. An inner member, an annular outer member concentrically arranged with the inner member, a plurality of tapered rollers interposed between the inner member and the outer member, and a cage provided between the inner member and the outer member for holding the plurality of tapered rollers, wherein the cage has an annular portion disposed on the large-diameter end face side of the plurality of tapered rollers, the inner member, has an axial hole penetrating the inner member in the axial direction, a large flange portion in sliding contact with the large-diameter end faces of the plurality of tapered rollers, and a through hole penetrating an outer peripheral surface connected to the large flange portion and the axial hole, wherein an axial position of an opening of the through hole on the outer peripheral surface is on the side of the plurality of tapered rollers rather than an axially leading end portion of the annular portion bearing device.

2. The annular portion has an annular protrusion protruding radially inward from an axially leading end portion of the annular portion The bearing device according to claim 1.

3. The inner peripheral surface of the annular portion includes an inclined surface that gradually increases in diameter from the axially leading end portion side of the annular portion toward the plurality of tapered rollers side The bearing device according to claim 1.

4. The outer peripheral surface has an annular stepped portion protruding radially outward, wherein the stepped portion is provided axially between an opening of the through hole and an axially leading end portion of the annular portion The bearing device according to claim 1.

5. The inner member has a shaft-shaped main body portion and a gear portion centered on the axis of the main body portion The bearing device according to any one of claims 1 to 4.

6. An inner ring, an outer ring concentrically arranged with the inner ring, a plurality of tapered rollers interposed between the inner ring and the outer ring, and a cage provided between the inner ring and the outer ring for holding the plurality of tapered rollers, wherein the cage has an annular portion disposed on the large-diameter end face side of the plurality of tapered rollers, the inner ring, has a large flange portion in sliding contact with the large-diameter end faces of the plurality of tapered rollers, and a through hole penetrating an outer peripheral surface connected to the large flange portion and an inner peripheral surface of the inner ring, wherein an axial position of an opening of the through hole on the outer peripheral surface is on the side of the plurality of tapered rollers rather than an axially leading end portion of the annular portion tapered roller bearing.

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