Bearing device

Abstract

To provide a bearing device having a plurality of rows of inner rings and a tapered roller, which suppresses a seizure between a large-diameter end face of a tapered roller and a collar face of an inner ring.SOLUTION: A bearing device 1 includes: an outer ring 10 having a pair of first raceway face 11 and second raceway face 12 formed on one side and the other side in an axial direction on an inner peripheral side; a pair of first inner ring 20a and second inner ring 20b having inner ring raceway faces 21 on an outer peripheral side and provided on one side and the other side in the axial direction; a plurality of tapered rollers 30; and a pair of retainers 40. The first inner ring 20a and the second inner ring 20b are coaxially arranged with a gap between end faces in the axial direction, and a lubrication oil is supplied from a radial inner side between the first inner ring 20a and the second inner ring 20b in the axial direction. The outer ring 10 includes a projection part 15 that projects to a radial inner side from an inner peripheral face 10a between the first raceway face 11 and the second raceway face 12, and is inserted into the gap.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to a bearing device.

Background Art

[0002] For example, in a planetary gear mechanism used in an automobile transmission, a bearing device used for supporting a planetary gear is disclosed in Patent Document 1. The bearing device is a double-row cylindrical roller bearing having double-row inner rings and tapered rollers.

[0003] FIG. 6 is a cross-sectional view at a position including the center line of a conventional bearing device, and is an explanatory view showing the flow of lubricating oil. The conventional bearing device 101 shown in FIG. 6 is a double-row cylindrical roller bearing. As shown in FIG. 6, the bearing device 101 includes an outer ring 110, inner rings 120, tapered rollers 130, and a cage 140.

[0004] The outer ring 110 has a first outer ring raceway surface 111 and a second outer ring raceway surface 112 on its inner peripheral surface 110a. The inner rings 120 include a first inner ring 120a disposed on one axial side and a second inner ring 120b disposed on the other axial side. The inner rings 120 have an inner ring raceway surface 121 formed on their outer peripheral surfaces, and a small flange portion 122 and a large flange portion 123. The first inner ring 120a and the second inner ring 120b are arranged coaxially with a gap between the small flange portions 122 facing each other. The tapered rollers 130 have a small-diameter side end face 131, a large-diameter side end face 132, and an outer peripheral surface 133. A plurality of tapered rollers 130 are arranged between the first outer ring raceway surface 111 and the inner ring raceway surface 121, and between the second outer ring raceway surface 112 and the inner ring raceway surface 121, respectively. The cage 140 has a small-diameter annular portion 141 and pockets 142. The cage 140 includes a first cage 140a disposed on one axial side and a second cage 140b disposed on the other axial side. The first cage 140a holds a plurality of tapered rollers 130 between the first outer ring raceway surface 111 and the inner ring raceway surface 121. The second cage 140b holds a plurality of tapered rollers 130 between the second outer ring raceway surface 112 and the inner ring raceway surface 121.

[0005] The bearing device 101 is mounted on the shaft 150 with the center line C0 of the bearing device 101 aligned with the center line C2 of the shaft 150. The bearing device 101 is axially sandwiched between a pair of nuts 153 screwed onto the shaft 150 and mounted on the shaft 150, and a preload is applied thereto. Lubricating oil is supplied to the bearing device 101 from a hydraulic pump (not shown) through the shaft hole 151 and the oil supply hole 152 toward the gap between the first inner ring 120a and the second inner ring 120b from the radially inner side.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] In the conventional bearing device 101 shown in FIG. 6, the lubricating oil supplied from the oil supply hole 152 flows radially outward by the action of centrifugal force, and after reaching the inner peripheral surface 110a of the outer ring 110, it flows to one side and the other side in the axial direction. At this time, the lubricating oil flows into the space between the outer ring 110 and the cage 140 and flows along the first outer ring raceway surface 111 and the second outer ring raceway surface 112. In this case, the amount of lubricating oil flowing into the space between the small-diameter annular portion 141 and the small flange portion 122 decreases, and it becomes difficult for the lubricating oil to reach the sliding portion between the large-diameter side end surface 132 and the flange surface 124 of the large flange portion 123. For this reason, in the conventional bearing device 101, there is a concern about seizure of the lubricated portion.

[0008] An object of the present disclosure is to suppress the occurrence of seizure between the large-diameter side end surface of a tapered roller and the flange surface of an inner ring in a bearing device having a double-row inner ring and tapered rollers.

Means for Solving the Problems

[0009] The bearing device of the present disclosure includes an outer ring having a pair of outer ring raceway surfaces formed on one axial side and the other axial side on the inner peripheral side, and an inner ring raceway surface, a small flange portion provided at one axial end side of the inner ring raceway surface, and a large flange portion provided at the other axial end side of the inner ring raceway surface on the outer peripheral side. A pair of inner rings arranged on one axial side and the other axial side, a plurality of tapered rollers arranged between the outer ring raceway surface and the inner ring raceway surface, and between the outer ring raceway surface and the inner ring raceway surface on one axial side, and between the outer ring raceway surface and the inner ring raceway surface on the other axial side, a pair of cages for holding the plurality of tapered rollers respectively. The large-diameter side end surface of the tapered roller is in rolling contact with the flange surface of the large flange portion. The pair of inner rings are coaxially arranged with a gap between the end surfaces in the axial direction, and lubricating oil is supplied from the radially inner side between the pair of inner rings in the axial direction toward the gap. The outer ring has a protruding portion that protrudes radially inward from the inner peripheral surface between the pair of outer ring raceway surfaces and is inserted into the gap.

[0010] According to the present disclosure, in a bearing device having a double-row inner ring and tapered rollers, it is possible to suppress the occurrence of seizure between the large-diameter side end surface of the tapered roller and the flange surface of the inner ring.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Best Mode for Carrying Out the Invention

[0012] <Summary of Embodiments of the Present Disclosure> The summary of the embodiments of the invention of the present disclosure will be listed and described below.

[0013] (1) The bearing device of the present disclosure includes an outer ring having a pair of outer ring raceway surfaces formed on one axial side and the other axial side on the inner peripheral side, an inner ring raceway surface, a small flange portion provided on one axial end side of the inner ring raceway surface, and a large flange portion provided on the other axial end side of the inner ring raceway surface on the outer peripheral side, a pair of inner rings arranged on one axial side and the other axial side, a plurality of tapered rollers arranged between the outer ring raceway surface and the inner ring raceway surface, and a pair of cages that respectively hold the plurality of tapered rollers between the outer ring raceway surface and the inner ring raceway surface on one axial side and between the outer ring raceway surface and the inner ring raceway surface on the other axial side. The large-diameter side end surface of the tapered roller is in rolling contact with the flange surface of the large flange portion. The pair of inner rings are coaxially arranged with a gap between their axial end surfaces, and lubricating oil is supplied from the radially inner side between the pair of inner rings in the axial direction toward the gap. The outer ring has a protruding portion that protrudes radially inward from the inner peripheral surface between the pair of outer ring raceway surfaces and is inserted into the gap.

[0014] According to the bearing device, the lubricating oil can be guided by the protruding portion and flow radially inward from the inner peripheral surface of the outer ring. Thereby, in a bearing device having a double-row inner ring and tapered rollers, the occurrence of seizure between the large-diameter side end surface of the tapered roller and the flange surface of the inner ring can be suppressed.

[0015] (2) In the bearing device according to the aspect (1), it is preferable that the cage has a small-diameter annular portion facing the small-diameter side end surface of the tapered roller, and the inner diameter of the protruding portion is equal to or less than the inner diameter of the small-diameter annular portion. According to this configuration, the lubricating oil can be guided by the protruding portion between the small-diameter annular portion of the cage and the small flange portion of the inner ring. With such a configuration, it becomes possible to supply lubricating oil between the large-diameter side end surface of the tapered roller and the flange surface of the inner ring.

[0016] (3) In the bearing device according to the form of (1) or (2) above, it is preferable that the inner diameter of the protruding portion is equal to or larger than the outer diameter of the small flange portion. According to this configuration, the protruding portion can surely guide the lubricating oil between the small-diameter annular portion of the cage and the small flange portion of the inner ring. With such a configuration, it becomes possible to supply lubricating oil between the large-diameter side end face of the tapered roller and the flange face of the inner ring.

[0017] (4) In the bearing device according to the form of (1) or (2) above, it is preferable that the inner peripheral surface of the protruding portion has a first inclined surface whose inner diameter dimension expands toward one side in the axial direction and a second inclined surface whose inner diameter dimension expands toward the other side in the axial direction. According to this configuration, the lubricating oil can be guided by the first inclined surface and the second inclined surface and flowed radially inward from the inner peripheral surface of the outer ring. Thereby, in a bearing device having a double-row inner ring and tapered rollers, it is possible to suppress the occurrence of seizure between the large-diameter side end face of the tapered roller and the flange face of the inner ring.

[0018] (5) In the bearing device according to the form of (4) above, the cage has a small-diameter annular portion facing the small-diameter side end face of the tapered roller, and in a cross section including the center line of the outer ring, the extension line of the first inclined surface and the extension line of the second inclined surface preferably pass between the small-diameter annular portion and the small flange portion. According to this configuration, the first inclined surface and the second inclined surface can surely guide the lubricating oil between the small-diameter annular portion of the cage and the small flange portion of the inner ring. With such a configuration, it becomes possible to supply lubricating oil between the large-diameter side end face of the tapered roller and the flange face of the inner ring.

[0019] (6) In the bearing device according to any one of the forms of (1) to (5) above, it is preferable that the outer ring is provided with gear teeth on the outer peripheral surface. According to this configuration, it is possible to suppress the occurrence of seizure between the large-diameter side end face of the tapered roller and the flange face of the inner ring under conditions where the lubricating oil is likely to scatter due to the centrifugal force generated by the driving of the gear.

[0020] [Overall Structure of the Bearing Device] FIG. 1 is a cross-sectional view taken at a position including the center line of the bearing device according to the first embodiment of the present disclosure. FIG. 2 is a partially enlarged view of the cross-sectional view shown in FIG. 1. FIGS. 1 and 2 show a bearing device 1 according to the first embodiment of the present disclosure. The bearing device 1 of the present disclosure shown in FIGS. 1 and 2 is a double-row cylindrical roller bearing having a double-row inner ring and a double-row tapered roller. In the following description, the bearing device 1 according to the first embodiment is also referred to as the first bearing device 1A. In the following description, when simply referred to as "bearing device 1", the common configuration in the first bearing device 1A and the bearing device 1 according to the second embodiment (see the second bearing device 1B shown in FIG. 4) to be described later is described.

[0021] As shown in FIGS. 1 and 2, the bearing device 1 includes an outer ring 10, a pair of inner rings 20 provided radially inward of the outer ring 10, a plurality of tapered rollers 30 provided between the outer ring 10 and the inner rings 20, and a pair of cages 40 for holding the tapered rollers 30.

[0022] The "axial direction" and "radial direction" in the description of each of the outer ring 10, inner ring 20, and cage 40 are defined. The "axial direction" is the direction along the center line of each of the outer ring 10, inner ring 20, and cage 40. Note that the axial direction includes a direction parallel to the center line. The "radial direction" is the direction orthogonal to each center line. Note that the direction along a circle centered on each center line is the circumferential direction. In each figure, the symbol of the center line in a state where the center lines of the outer ring 10, inner ring 20, and cage 40 coincide with each other is "C1".

[0023] The "axial direction" in the description of the tapered roller 30 is defined. The "axial direction" of the tapered roller 30 is the direction along the center line of the tapered roller 30. In order to distinguish it from the "axial direction" of the outer ring 10, inner ring 20, and cage 40, the axial direction of the tapered roller 30 may be referred to as the "roller axial direction". Note that the roller axial direction includes a direction parallel to the center line.

[0024] The outer ring 10 shown in FIGS. 1 and 2 is an annular member formed using bearing steel, steel for machine structures, or the like. As shown in FIGS. 1 and 2, in the bearing device 1 of the present disclosure, the outer ring 10 includes a tapered first raceway surface (outer ring raceway surface) 11 formed on one axial side of the inner peripheral surface 10a, and a tapered second raceway surface (outer ring raceway surface) 12 formed on the other axial side of the inner peripheral surface 10a.

[0025] The outer ring 10 of the present embodiment further includes gear teeth 13 on the outer peripheral surface. The outer ring 10 of the present embodiment is a gear and is used as a planetary gear that constitutes a planetary gear mechanism. The outer ring 10, which is a planetary gear, is driven in response to the rotation of a sun gear and / or a ring gear (not shown). Note that in the bearing device of the present disclosure, the outer ring does not have to be a gear, and in this case, the teeth of the outer ring may be omitted.

[0026] The inner ring 20 shown in FIGS. 1 and 2 is an annular member formed using bearing steel, steel for machine structures, or the like. As shown in FIGS. 1 and 2, in the bearing device 1 of the present disclosure, the inner ring 20 includes a first inner ring 20a disposed on one axial side and a second inner ring 20b disposed on the other axial side. The inner ring 20 (the first inner ring 20a and the second inner ring 20b) has a tapered inner ring raceway surface 21 formed on the outer peripheral surface. The inner ring raceway surface 21 of the first inner ring 20a faces the first raceway surface 11. The inner ring raceway surface 21 of the second inner ring 20b faces the second raceway surface 12.

[0027] The inner ring 20 (the first inner ring 20a and the second inner ring 20b) further has a small flange portion 22 and a large flange portion 23. The small flange portion 22 and the large flange portion 23 each project radially outward. The first inner ring 20a and the second inner ring 20b are coaxially arranged with a gap between the axial end faces of the two small flange portions 22.

[0028] The tapered roller 30 is a tapered trapezoidal member formed using bearing steel or the like. The tapered roller 30 has a small-diameter side end face 31, a large-diameter side end face 32, and an outer peripheral face 33. The small-diameter side end face 31 is a circular part with a small diameter located on one side in the roller axis direction and faces the small flange portion 22 of the inner ring 20. The large-diameter side end face 32 is a circular part with a large diameter located on the other side in the roller axis direction and faces the flange face 24 of the large flange portion 23 of the inner ring 20. A plurality of the tapered rollers 30 are arranged between the first raceway surface 11 and the inner ring raceway surface 21 of the first inner ring 20a. These tapered rollers 30 rollingly contact the first raceway surface 11 and the inner ring raceway surface 21. A plurality of the tapered rollers 30 are arranged between the second raceway surface 12 and the inner ring raceway surface 21 of the second inner ring 20b. These tapered rollers 30 rollingly contact the second raceway surface 12 and the inner ring raceway surface 21. The small-diameter side end face 31 rollingly contacts the small flange portion 22. The large-diameter side end face 32 rollingly contacts the flange face 24 of the large flange portion 23.

[0029] The cage 40 is made of synthetic resin and is formed in an annular shape by injection molding. The cage 40 of the present embodiment is made of, for example, polyphenylene sulfide resin (PPS). The cage 40 has resistance (oil resistance) to lubricating oil, is relatively hard, and is difficult to elastically deform.

[0030] The cage 40 has a plurality of pockets 42 for accommodating the tapered rollers 30 and holds the plurality of tapered rollers 30 at equal intervals in the circumferential direction. The cage 40 includes an annular small-diameter annular portion 41 formed at one end in the axial direction. The small-diameter annular portion 41 faces the small-diameter side end face 31 of the tapered roller 30 accommodated in the pocket 42.

[0031] In the bearing device 1 of the present disclosure, the cage 40 includes a first cage 40a and a second cage 40b. The first cage 40a and the second cage 40b are coaxially arranged with the axial end faces of the small-diameter annular portions 41 facing each other. The axial end faces of both small-diameter annular portions 41 face each other axially with a gap therebetween. The first cage 40a is arranged on one axial side. The first cage 40a holds a plurality of tapered rollers 30 that rollingly contact the first raceway surface 11 and the inner raceway surface 21 of the first inner ring 20a. The second cage 40b is arranged on the other axial side. The second cage 40b holds a plurality of tapered rollers 30 that rollingly contact the second raceway surface 12 and the inner raceway surface 21 of the second inner ring 20b.

[0032] As shown in FIGS. 1 and 2, in the bearing device 1 of the present disclosure, the outer ring 10 is provided with a protruding portion 15. The protruding portion 15 is an annular portion that protrudes radially inward from the inner peripheral surface 10a between the first raceway surface 11 and the second raceway surface 12. The protruding portion 15 extends radially inward toward the gap formed between the first inner ring 20a and the second inner ring 20b and is inserted into the gap. Further, the protruding portion 15 is inserted into the gap formed between the opposing small-diameter annular portions 41.

[0033] [Regarding the usage state of the bearing device] FIG. 3 is an explanatory diagram showing the mounting state of the bearing device with respect to the shaft and the flow of lubricating oil. As shown in FIG. 3, the bearing device 1 is mounted and used with respect to the shaft 50. The shaft 50 of the present embodiment is a shaft that supports a planetary gear provided on a planetary carrier. The shaft 50 is provided with a shaft hole 51 and an oil supply hole 52 for supplying lubricating oil. In each figure, the reference sign of the center line of the shaft 50 is "C2".

[0034] The bearing device 1 is mounted on the shaft 50 with the inner ring 20 inserted through the shaft 50 with the center line C1 aligned with the center line C2 of the shaft 50. The bearing device 1 is axially sandwiched between a pair of nuts 53 screwed onto the shaft 50 and mounted on the shaft 50, and a preload is applied.

[0035] As shown in Fig. 3, lubricating oil is supplied from a hydraulic pump (not shown) through the shaft hole 51 and the oil supply hole 52 toward the gap between the first inner ring 20a and the second inner ring 20b from the radially inner side.

[0036] [Regarding the first bearing device] As shown in Figs. 1 to 3, in the first bearing device 1A, the protruding portion 15 provided on the outer ring 10 has an inner peripheral surface 16.

[0037] As shown in Fig. 3, in the first bearing device 1A, the lubricating oil discharged radially outward from the oil supply hole 52 flows radially outward by centrifugal force and reaches the protruding portion 15. Next, the lubricating oil flows axially along the inner peripheral surface 16 and reaches between the small-diameter annular portion 41 and the small flange portion 22. Next, the lubricating oil flows into the space between the small-diameter annular portion 41 and the small flange portion 22 and flows toward the tapered roller 30. Then, the lubricating oil flows along the outer peripheral surface 33 and reaches between the large-diameter side end surface 32 of the tapered roller 30 and the large flange portion 23. In this way, the first bearing device 1A supplies lubricating oil between the large-diameter side end surface 32 and the flange surface 24 of the large flange portion 23. Thereby, the occurrence of seizure between the large-diameter side end surface 32 and the flange surface 24 can be suppressed.

[0038] As shown in Fig. 2, in the first bearing device 1A, it is preferable that the inner diameter φP of the inner peripheral surface 16 is a dimension equal to or less than the inner diameter φQ of the small-diameter annular portion 41 of the cage 40 (φP ≦ φQ). In this case, the lubricating oil can flow along the inner peripheral surface 16 radially inside the small-diameter annular portion 41. Thereby, it is possible to suppress the lubricating oil from flowing along the first raceway surface 11 and the second raceway surface 12, and it is possible to suppress a decrease in the lubricating oil flowing between the small-diameter annular portion 41 and the small flange portion 22.

[0039] Further, in the first bearing device 1A, it is more preferable that the inner diameter φP of the inner peripheral surface 16 is a dimension equal to or greater than the outer diameter φR of the small flange portion 22 of the inner ring 20 (φR ≦ φP). In this case, the lubricating oil can flow along the inner peripheral surface 16 radially outside the small flange portion 22. Thereby, the lubricating oil can be reliably guided between the large-diameter side end surface 32 and the flange surface 24 of the large flange portion 23.

[0040] The first bearing device 1A sets the dimensional relationship among the inner diameter φP of the inner peripheral surface 16, the inner diameter φQ of the small-diameter annular portion 41, and the outer diameter φR of the small flange portion 22 of the inner ring 20 as the relationship of (φR ≤ φP ≤ φQ), so that the lubricating oil reaching the inner peripheral surface 16 can be surely made to flow between the small-diameter annular portion 41 and the small flange portion 22. According to the first bearing device 1A having such a configuration, lubricating oil can be surely supplied between the large-diameter side end face 32 and the flange face 24.

[0041] [Regarding the second bearing device] FIG. 4 is a cross-sectional view at a position including the center line of the bearing device according to the second embodiment of the present disclosure. FIG. 5 is a partially enlarged view of the cross-sectional view shown in FIG. 4. FIGS. 4 and 5 show a bearing device 1 according to the second embodiment of the present disclosure. In the following description, the bearing device 1 according to the second embodiment is also referred to as a second bearing device 1B.

[0042] As shown in FIGS. 4 and 5, in the second bearing device 1B, the inner peripheral surface 16 of the protruding portion 15 includes a first inclined surface (hereinafter referred to as a first inclined surface 16a) and a second inclined surface (hereinafter referred to as a second inclined surface 16b), and this point is different from the first bearing device 1A (see FIG. 1). Note that the second bearing device 1B is common with the first bearing device 1A in other configurations.

[0043] In the second bearing device 1B, the first inclined surface 16a and the second inclined surface 16b have an inclination capable of guiding lubricating oil between the small-diameter annular portion 41 and the small flange portion 22. In the second bearing device 1B, the lubricating oil reaching the protruding portion 15 flows along the first inclined surface 16a and the second inclined surface 16b. At this time, the lubricating oil flows toward between the small-diameter annular portion 41 and the small flange portion 22. According to the second bearing device 1B having such a configuration, lubricating oil can be surely supplied between the large-diameter side end face 32 and the flange face 24. Thereby, the occurrence of seizure between the large-diameter side end face 32 and the flange face 24 can be suppressed.

[0044] As shown in Fig. 5, in the second bearing device 1B, it is preferable that the extension lines L1 and L2 of the first inclined surface 16a and the second inclined surface 16b pass between the small-diameter annular portion 41 and the small flange portion 22, respectively. The extension line L1 of the first inclined surface 16a is a line obtained by extending the first inclined surface 16a in a cross section including the center line C1 of the second bearing device 1B, and the extension line L2 of the second inclined surface 16b is a line obtained by extending the second inclined surface 16b in a cross section including the center line C1. In such a configuration, the lubricating oil reaching the protruding portion 15 can be guided by the first inclined surface 16a and the second inclined surface 16b and reliably made to flow between the small-diameter annular portion 41 and the small flange portion 22. According to the second bearing device 1B having such a configuration, lubricating oil can be reliably supplied between the large-diameter side end surface 32 and the flange surface 24.

[0045] [Actions and Effects of the Present Embodiment] (1) The bearing device 1 of the above embodiment includes an outer ring 10 having a pair of outer ring raceway surfaces (first raceway surface 11 and second raceway surface 12) formed on one side and the other side in the axial direction on the inner peripheral side, and an inner ring raceway surface 21, a small flange portion 22 provided at one axial end side of the inner ring raceway surface 21, and a large flange portion 23 provided at the other axial end side of the inner ring raceway surface 21 on the outer peripheral side. A pair of inner rings 20 (first inner ring 20a and second inner ring 20b) arranged on one side and the other side in the axial direction, a plurality of tapered rollers 30 arranged between each raceway surface 11, 12 and the inner ring raceway surface 21, and a pair of cages 40a, 40b that respectively hold the plurality of tapered rollers 30 between the first raceway surface 11 and the inner ring raceway surface 21 and between the second raceway surface 12 and the inner ring raceway surface 21. The large-diameter side end surface 32 of the tapered roller 30 rolls and contacts the flange surface 24 of the large flange portion 23. The pair of inner rings 20 (first inner ring 20a and second inner ring 20b) are coaxially arranged with a gap between their end surfaces in the axial direction, and lubricating oil is supplied from the radially inner side between the first inner ring 20a and the second inner ring 20b in the axial direction toward the gap. The outer ring 10 has a protruding portion 15 that protrudes radially inward from the inner peripheral surface 10a between the first raceway surface 11 and the second raceway surface 12 and is inserted into the gap.

[0046] According to the bearing device 1 of the above embodiment, the lubricating oil can be guided by the protruding portion 15 and flow radially inward from the inner peripheral surface 10a of the outer ring 10. Thereby, in the bearing device 1 having the double-row inner ring 20 and the tapered roller 30, it is possible to suppress the occurrence of seizure between the large-diameter side end surface 32 of the tapered roller 30 and the flange surface 24 of the inner ring 20.

[0047] (2) In the bearing device 1 of the above embodiment, the cage 40 has a small-diameter annular portion 41 facing the small-diameter side end surface 31 of the tapered roller 30. The inner diameter φP of the protruding portion 15 is equal to or less than the inner diameter φQ of the small-diameter annular portion 41. According to the configuration of the above embodiment, the lubricating oil can be guided by the protruding portion 15 between the small-diameter annular portion 41 of the cage 40 and the small flange portion 22 of the inner ring 20. With such a configuration, it becomes possible to supply the lubricating oil between the large-diameter side end surface 32 of the tapered roller 30 and the flange surface 24 of the inner ring 20.

[0048] (3) In the bearing device 1 of the above embodiment, the inner diameter φP of the protruding portion 15 is equal to or greater than the outer diameter φR of the small flange portion 22. According to the configuration of the above embodiment, the lubricating oil can be reliably guided by the protruding portion 15 between the small-diameter annular portion 41 of the cage 40 and the small flange portion 22 of the inner ring 20. With such a configuration, it becomes possible to reliably supply the lubricating oil between the large-diameter side end surface 32 of the tapered roller 30 and the flange surface 24 of the inner ring 20.

[0049] (4) In the bearing device 1 of the above embodiment, the inner peripheral surface 16 of the protruding portion 15 has a first inclined surface 16a whose inner diameter dimension expands toward one axial side, and a second inclined surface 16b whose inner diameter dimension expands toward the other axial side. According to the configuration of the above embodiment, the lubricating oil can be guided by the first inclined surface 16a and the second inclined surface 16b and flow radially inward from the inner peripheral surface 10a of the outer ring 10. Thereby, in the bearing device 1 having the double-row inner ring 20 and the tapered roller 30, it is possible to suppress the occurrence of seizure between the large-diameter side end surface 32 of the tapered roller 30 and the flange surface 24 of the inner ring 20.

[0050] (5) In the bearing device 1 of the above-described embodiment, the cage 40 has a small-diameter annular portion 41 facing the small-diameter side end face 31 of the tapered roller 30. In a cross-section including the center line C1 of the outer ring 10, the extension line L1 of the first inclined surface 16a and the extension line L2 of the second inclined surface 16b pass between the small-diameter annular portion 41 and the small flange portion 22. According to the configuration of the above-described embodiment, the first inclined surface 16a and the second inclined surface 16b can surely guide the lubricating oil between the small-diameter annular portion 41 of the cage 40 and the small flange portion 22 of the inner ring 20. With such a configuration, it becomes possible to surely supply the lubricating oil between the large-diameter side end face 32 of the tapered roller 30 and the flange surface 24 of the inner ring 20.

[0051] (6) In the bearing device 1 of the above-described embodiment, the outer ring 10 is provided with gear teeth 13 on the outer peripheral surface. According to the configuration of the above-described embodiment, it is possible to suppress the occurrence of seizure between the large-diameter side end face 32 of the tapered roller 30 and the flange surface 24 of the inner ring 20 under conditions where the centrifugal force generated by the driving of the outer ring 10, which is a gear, makes the lubricating oil likely to scatter.

[0052] The forms disclosed this time are illustrative in all respects and not restrictive. The scope of the rights of the present invention is not limited to the above-described forms, but includes all modifications within the scope equivalent to the configurations described in the claims.

Explanation of Reference Numerals

[0053] 1 Bearing device 10 Outer ring 10a Inner peripheral surface 11 First raceway surface (outer ring raceway surface) 12 Second raceway surface (outer ring raceway surface) 13 Teeth 15 Protrusion 16 Inner peripheral surface 16a First inclined surface (first inclined surface) 16b Second inclined surface (second inclined surface) 20 Inner ring 20a First inner ring 20b Second inner ring 21 Inner ring raceway surface 22 Small flange part 23 Large flange part 24 Flange surface 30 Ball 31 Small-diameter side end face 32 Large-diameter side end face 40 Retainer 41 Small-diameter ring part φP (Inner diameter of the protruding part) φQ (Inner diameter of the small-diameter ring part) φR (Outer diameter of the small flange part)

Claims

1. an outer ring having a pair of outer raceway surfaces formed on one axial side and the other axial side on the inner peripheral side; a pair of inner rings having an inner raceway surface, a small flange portion provided at one axial end side of the inner raceway surface, and a large flange portion provided at the other axial end side of the inner raceway surface, and arranged on one axial side and the other axial side; a plurality of tapered rollers disposed between the outer raceway surface and the inner raceway surface; a pair of cages that respectively hold the plurality of tapered rollers between the outer raceway surface and the inner raceway surface on one axial side and between the outer raceway surface and the inner raceway surface on the other axial side; comprising; the large-diameter side end surface of the tapered roller rolls in contact with the flange surface of the large flange portion; the pair of inner rings are coaxially arranged with a gap between their axial end surfaces, and lubricating oil is supplied from the radially inner side between the pair of inner rings in the axial direction toward the gap; the outer ring has a protruding portion that protrudes radially inward from the inner peripheral surface between the pair of outer raceway surfaces and is inserted into the gap, a bearing device.

2. the cage has a small-diameter annular portion facing the small-diameter side end surface of the tapered roller; the inner diameter of the protruding portion is equal to or less than the inner diameter of the small-diameter annular portion, the bearing device according to claim 1.

3. the inner diameter of the protruding portion is equal to or greater than the outer diameter of the small flange portion, the bearing device according to claim 1 or claim 2.

4. the inner peripheral surface of the protruding portion; has a first inclined surface whose inner diameter dimension expands toward one axial side; and a second inclined surface whose inner diameter dimension expands toward the other axial side, the bearing device according to claim 1 or claim 2.

5. the cage has a small-diameter annular portion facing the small-diameter side end surface of the tapered roller; in a cross section including the center line of the outer ring, the extension line of the first inclined surface and the extension line of the second inclined surface pass between the small-diameter annular portion and the small flange portion, the bearing device according to claim 4.

6. the outer ring is provided with gear teeth on its outer peripheral surface, the bearing device according to claim 1 or claim 2.

Images