Tapered roller bearing

Abstract

To provide a tapered roller bearing that can prevent interference between a recess on a large diameter side end face of the tapered roller and a cage.SOLUTION: A cage comprises: a large diameter side annular portion; a small diameter side annular portion arranged coaxially with the large diameter side annular portion; a plurality of column portions that axially connect the large diameter side annular portion and the small diameter side annular portion and are provided at approximately equal intervals in a circumferential direction; and a plurality of pocket portions that are formed respectively between an axial inner surface of the large diameter side annular portion, an axial inner surface of the small diameter side annular portion, and the column portions adjacent to each other in the circumferential direction, and that hold tapered rollers in a rollable manner. A recess is provided on a large diameter side end face of the tapered roller to be recessed axially inward. A recessed groove is provided on the axial inner surface of the large diameter side annular portion to be recessed axially outward, at least in a region overlapping with the recess of the tapered roller.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a tapered roller bearing. [Background technology]

[0002] Tapered roller bearings are suitably used to support the rotation of rotating shafts in various industrial machines such as railway cars, automobiles, construction machines, and steel rolling mills.

[0003] Fig. 5 is a cross-sectional view showing a conventional tapered roller bearing. As shown in Fig. 5, tapered roller bearing 100 comprises an outer ring 10 having an outer ring raceway surface 11 on its inner peripheral surface, an inner ring 20 having an inner ring raceway surface 21 on its outer peripheral surface, a plurality of tapered rollers 30 provided so as to be able to roll between outer ring raceway surface 11 and inner ring raceway surface 21, and a cage 40 that holds the plurality of tapered rollers 30 at approximately equal intervals in the circumferential direction.

[0004] The retainer 40 comprises a large diameter side annular portion 41, a small diameter side annular portion 43 arranged coaxially with the large diameter side annular portion 41, a plurality of pillar portions 45 that axially connect the large diameter side annular portion 41 and the small diameter side annular portion 43 and are arranged at approximately equal intervals in the circumferential direction, and a plurality of pocket portions 47 that are formed respectively between the axial inner surface 41a of the large diameter side annular portion 41, the axial inner surface 43a of the small diameter side annular portion 43, and the pillar portions 45 adjacent to each other in the circumferential direction, and that hold the tapered rollers 30 in a rollable manner.

[0005] In such a tapered roller bearing 100, the large diameter side end faces 31 of the tapered rollers 30 rotate while being guided by the large rib surface 23 of the inner ring 20. For this reason, as a countermeasure against wear, the large diameter side end faces 31 of the tapered rollers 30 and the large rib surface 23 of the inner ring 20 are ground. And, because the center portions of the large diameter side end faces 31 of the tapered rollers 30 do not come into contact with the large rib surface 23 of the inner ring 20, a grinding relief 33 is provided to reduce processing costs.

[0006] As in the example of Figure 5, when the large-diameter annular portion 41 of the cage 40 overlaps with the recess 33 of the tapered roller 30, the axially inner surface 41a of the large-diameter annular portion 41 interferes with the recess 33, which could result in wear of the cage 40. The possibility of wear tends to be particularly high in tapered roller bearings with steep contact angles or tapered roller bearings used at high speeds. If the generated wear debris gets caught in the rolling surface of the tapered roller bearing 100 or the tooth surface of the gear, problems could occur. One possible solution would be to reduce the diameter of the recess 33, but this would increase costs due to increased grinding time.

[0007] Patent Document 1 discloses a tapered roller bearing designed to prevent edge contact between the recessed portion of the large end face of the tapered roller and the large rib surface of the inner ring, thereby preventing damage such as wear and galling that is likely to occur on the large end face of the tapered roller and the large rib of the inner ring from the early stages of use. To this end, this tapered roller bearing forms a recessed portion of a predetermined diameter in the center of the large end face of the tapered roller, provides a sliding contact portion with the large rib surface in an annular area outside this diameter, provides a chamfer at the intersection edge between the large rib surface and the outer circumferential surface of the large rib, and provides a smooth flank at the boundary between this chamfered portion and the large rib surface. This eliminates the edge that would have formed at the boundary between the chamfered portion and the large rib surface, preventing edge contact. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Publication No. 2019-184018 Summary of the Invention [Problem to be solved by the invention]

[0009] However, the invention described in Patent Document 1 aims to prevent edge contact between the recessed portion on the large diameter side end face of the tapered roller and the large rib surface of the inner ring, and does not take into consideration interference between the recessed portion on the large diameter side end face of the tapered roller and the cage.

[0010] The present invention has been made in view of the above-mentioned problems, and its object is to provide a tapered roller bearing that can prevent interference between the relief on the large diameter side end face of the tapered roller and the cage. [Means for solving the problem]

[0011] Therefore, the above object of the present invention is achieved by the following configuration [1] relating to a tapered roller bearing. [1] An outer ring having an outer ring raceway on its inner circumferential surface; an inner ring having an inner ring raceway surface on its outer circumferential surface; a plurality of tapered rollers rollably provided between the outer ring raceway surface and the inner ring raceway surface; a cage that holds the plurality of tapered rollers at approximately equal intervals in the circumferential direction; A tapered roller bearing comprising: The retainer is a large diameter annular portion; a small diameter annular portion arranged coaxially with the large diameter annular portion; a plurality of pillar portions that connect the large diameter side annular portion and the small diameter side annular portion in the axial direction and are provided at approximately equal intervals in the circumferential direction; a plurality of pocket portions formed respectively between an axially inner surface of the large diameter side annular portion, an axially inner surface of the small diameter side annular portion, and the column portions adjacent to each other in the circumferential direction, and which hold the tapered rollers in a rollable manner; Equipped with A recess is provided on the large diameter side end surface of the tapered roller, the recess being recessed axially inward, a recessed groove is provided in an axially outward direction on at least a region of an axially inner surface of the large diameter side annular portion that overlaps with the relief of the tapered roller; A tapered roller bearing characterized by: [Effects of the Invention]

[0012] According to the tapered roller bearing of the present invention, it is possible to prevent interference between the clearance on the large diameter side end face of the tapered roller and the cage. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a cross-sectional view showing a tapered roller bearing according to this embodiment. [Figure 2] FIG. 2 is a perspective view showing tapered rollers assembled in a cage. [Figure 3] Figure 3(a) is a diagram showing the positional relationship between the tapered roller and the large-diameter annular portion of the retainer when viewed from the radial direction of the tapered roller, and Figure 3(b) is a diagram showing the positional relationship between the tapered roller and the large-diameter annular portion of the retainer when viewed from the axial direction of the tapered roller. [Figure 4] Figure 4(a) is a diagram showing the positional relationship between a tapered roller according to a modified example and the large diameter side annular portion of the retainer when viewed from the radial direction of the tapered roller, and Figure 4(b) is a diagram showing the positional relationship between a tapered roller according to a modified example and the large diameter side annular portion of the retainer when viewed from the axial direction of the tapered roller. [Figure 5] FIG. 5 is a cross-sectional view showing a conventional tapered roller bearing. DETAILED DESCRIPTION OF THE INVENTION

[0014] Fig. 1 is a cross-sectional view showing a tapered roller bearing according to this embodiment, and Fig. 2 is a perspective view showing tapered rollers incorporated into a cage.

[0015] As shown in Figures 1 and 2, the tapered roller bearing 1 comprises an outer ring 10 having an outer ring raceway surface 11 on its inner peripheral surface, an inner ring 20 having an inner ring raceway surface 21 on its outer peripheral surface, a plurality of tapered rollers 30 arranged to roll between the outer ring raceway surface 11 and the inner ring raceway surface 21, and a cage 40 that holds the plurality of tapered rollers 30 at approximately equal intervals in the circumferential direction.

[0016] The cage 40 includes a large-diameter side annular portion 41, a small-diameter side annular portion 43 arranged coaxially with the large-diameter side annular portion 41, a plurality of column portions 45 that axially connect the large-diameter side annular portion 41 and the small-diameter side annular portion 43 and are provided at approximately equal intervals in the circumferential direction, and a plurality of pocket portions 47 that are formed respectively between the axially inner surface 41a of the large-diameter side annular portion 41, the axially inner surface 43a of the small-diameter side annular portion 43, and the circumferentially adjacent column portions 45 and rollably hold the tapered rollers 30. Here, the axial direction refers to the axial direction of the tapered roller bearing 1, and is the left-right direction in FIG. 1. Furthermore, the axially inner side refers to the center side of the tapered roller bearing 1 in the axial direction, and is the left-right center side in FIG. 1. Furthermore, the axially outer side refers to the outside in the axial direction of the tapered roller bearing 1, and is both the left and right sides in FIG. 1.

[0017] In this type of tapered roller bearing 100, the large diameter side end faces 31 of the tapered rollers 30 rotate while being guided by the large rib surface 23 of the inner ring 20. For this reason, as a countermeasure against wear, the large diameter side end faces 31 of the tapered rollers 30 and the large rib surface 23 of the inner ring 20 are ground. And, because the central portions of the large diameter side end faces 31 of the tapered rollers 30 do not come into contact with the large rib surface 23 of the inner ring 20, a grinding relief 33 is provided to reduce processing costs. The large diameter side end face 31 includes a substantially planar annular surface 35 formed around the relief 33.

[0018] If the large-diameter-side annular portion 41 of the cage 40 were to overlap and come into contact with the recesses 33 of the tapered rollers 30, the axially inner surface 41a of the large-diameter-side annular portion 41 would interfere with the recesses 33, which could result in wear of the cage 40. Therefore, in this embodiment, grooves 42 are recessed axially outward in the axially inner surface 41a of the large-diameter-side annular portion 41 of the cage 40. The depth of the grooves 42 in FIG. 2 increases from both circumferential sides toward the circumferential center, but this does not limit the depth or shape of the grooves 42. Note that the grooves 42 are formed in regions of the axially inner surface 41a of the large-diameter-side annular portion 41 that form the pockets 47, and therefore the number of grooves 42 provided is the same as the number of tapered rollers 30 and pockets 47.

[0019] The recessed groove 42 will be described more specifically with reference to Figures 3(a) and 3(b). Figure 3(a) is a diagram showing the positional relationship between the tapered rollers 30 and the large diameter side annular portion 41 of the retainer 40 as viewed from the radial direction of the tapered rollers 30, and Figure 3(b) is a diagram showing the positional relationship between the tapered rollers 30 and the large diameter side annular portion 41 of the retainer 40 as viewed from the axial direction of the tapered rollers 30.

[0020] As shown in Figures 3(a) and 3(b), a recessed groove 42 is recessed axially outward in an area T of the axially inner surface 41a of the large-diameter side annular portion 41 of the retainer 40 that overlaps at least with the recess 33 of the tapered roller 30. Here, the area T where the axially inner surface 41a of the large-diameter side annular portion 41 of the retainer 40 and the recess 33 of the tapered roller 30 overlap is the area where they overlap when viewed from the axial direction of the tapered roller 30, as shown in Figure 3(b). In Figure 3(b), the area T is hatched with diagonal lines.

[0021] If the recessed groove 42 is formed in at least the region T of the axially inner surface 41a of the large diameter side annular portion 41 of the retainer 40, interference between the relief 33 of the tapered roller 30 and the large diameter side annular portion 41 of the retainer 40 can be prevented.

[0022] The recessed groove 42 in this embodiment is formed over an area wider than the region T. That is, both circumferential end portions 42a, 42a of the recessed groove 42 are located circumferentially outer than the region T, and the radially outer end portion 42b of the recessed groove 42 is located radially outer than the region T. By forming the recessed groove 42 over an area that includes the region T and is wider than the region T in this way, interference between the relief 33 of the tapered roller 30 and the large-diameter-side annular portion 41 of the retainer 40 is prevented even when the tapered rollers 30 and the retainer 40 are inclined relative to each other.

[0023] The recessed grooves 42 are preferably formed from the radially inner end to the radially outer end of the axially inner surface 41a of the large-diameter-side annular portion 41. With this configuration, the recessed grooves 42 are easy to process, and by forming the recessed grooves 42 over a wide range in the radial direction, the effect of preventing interference between the reliefs 33 of the tapered rollers 30 and the large-diameter-side annular portion 41 of the cage 40 is improved.

[0024] In this embodiment, both circumferential end portions 42a, 42a of the recessed groove 42 extend in a substantially straight line in the radial direction, which makes it easy to process the recessed groove 42.

[0025] Furthermore, both circumferential end portions 42a, 42a of the recessed groove 42 are formed in an area where the axially inner surface 41a of the large-diameter side annular portion 41 overlaps with the annular surface 35 of the tapered roller 30. This prevents the recessed groove 42 from being formed too large, ensures an area where the axially inner surface 41a of the large-diameter side annular portion 41 contacts with the annular surface 35 of the tapered roller 30, and enables the cage 40 to reliably hold the tapered roller 30.

[0026] The present invention is not limited to the above-described embodiment, and modifications and improvements are possible as appropriate.

[0027] For example, the shape of the recessed groove 42 is not particularly limited, and shapes such as those shown in Figures 4(a) and 4(b) may be adopted. Figure 4(a) is a diagram showing the positional relationship between the tapered rollers 30 according to a modified example and the large diameter side annular portion 41 of the cage 40, as viewed from the radial direction of the tapered rollers 30, and Figure 4(b) is a diagram showing the positional relationship between the tapered rollers 30 according to a modified example and the large diameter side annular portion 41 of the cage 40, as viewed from the axial direction of the tapered rollers 30. As shown in Figures 4(a) and 4(b), both circumferential end portions 42a, 42a of the recessed groove 42 may extend in a generally V-shape so as to approach each other circumferentially from the radially inner side toward the radially outer side.

[0028] As described above, the present specification discloses the following: (1) an outer ring having an outer ring raceway on its inner circumferential surface; an inner ring having an inner ring raceway surface on its outer circumferential surface; a plurality of tapered rollers rollably provided between the outer ring raceway surface and the inner ring raceway surface; a cage that holds the plurality of tapered rollers at approximately equal intervals in the circumferential direction; A tapered roller bearing comprising: The retainer is a large diameter annular portion; a small diameter annular portion arranged coaxially with the large diameter annular portion; a plurality of pillar portions that connect the large diameter side annular portion and the small diameter side annular portion in the axial direction and are provided at approximately equal intervals in the circumferential direction; a plurality of pocket portions formed respectively between an axially inner surface of the large diameter side annular portion, an axially inner surface of the small diameter side annular portion, and the column portions adjacent to each other in the circumferential direction, and which hold the tapered rollers in a rollable manner; Equipped with A recess is provided on the large diameter side end surface of the tapered roller, the recess being recessed axially inward, a recessed groove is provided in an axially outward direction on at least a region of an axially inner surface of the large diameter side annular portion that overlaps with the relief of the tapered roller; A tapered roller bearing characterized by: (2) Both circumferential end portions of the recessed groove are located circumferentially outward of a region where an axially inner surface of the large-diameter-side annular portion and the relief of the tapered roller overlap, a radially outer end portion of the recessed groove is located radially outward of a region where an axially inner surface of the large-diameter-side annular portion and the relief of the tapered roller overlap; (1) A tapered roller bearing according to the present invention. (3) The large diameter side end surface of the tapered roller includes an annular surface formed around the relief, Both circumferential end portions of the recessed groove are formed in a region where an axially inner surface of the large diameter side annular portion and the annular surface of the tapered roller overlap. (2) A tapered roller bearing according to the present invention. (4) The recessed groove is formed on the axially inner surface of the large-diameter annular portion from a radially inner end to a radially outer end. The tapered roller bearing according to any one of (1) to (3). (5) Both circumferential ends of the recessed groove extend substantially linearly in the radial direction. The tapered roller bearing according to any one of (1) to (4). (6) Both circumferential end portions of the recessed groove extend so as to approach each other in the circumferential direction from the radially inner side toward the radially outer side. The tapered roller bearing according to any one of (1) to (4). [Explanation of symbols]

[0029] 1. Bearings 10 outer ring 11 Outer ring raceway 20 Inner Circle 21 Inner ring raceway surface 23 Large Tsuba Face 31 Large diameter side end face 33 Escape 35 Annular Surface 40 Retainer 41 Large diameter annular portion 41a, 43a Axial inner surface 42 Groove 42a Circumferential ends 42b Radial outer end 43 Small diameter side annular part 45 Pillar section 47 Pocket

Claims

1. an outer ring having an outer ring raceway surface on its inner circumferential surface; an inner ring having an inner ring raceway surface on its outer circumferential surface; a plurality of tapered rollers rollably provided between the outer ring raceway surface and the inner ring raceway surface; a cage that holds the plurality of tapered rollers at approximately equal intervals in the circumferential direction; A tapered roller bearing comprising: The retainer is a large diameter annular portion; a small diameter annular portion arranged coaxially with the large diameter annular portion; a plurality of pillar portions that connect the large diameter side annular portion and the small diameter side annular portion in the axial direction and are provided at approximately equal intervals in the circumferential direction; a plurality of pocket portions formed respectively between an axially inner surface of the large diameter side annular portion, an axially inner surface of the small diameter side annular portion, and the column portions adjacent to each other in the circumferential direction, and which hold the tapered rollers in a rollable manner; Equipped with A recess is provided on the large diameter side end surface of the tapered roller, the recess being recessed axially inward, a recessed groove is provided in an axially outward direction on at least a region of an axially inner surface of the large diameter side annular portion that overlaps with the relief of the tapered roller; A tapered roller bearing characterized by:

2. both circumferential end portions of the recessed groove are located circumferentially outward of a region where an axially inner surface of the large-diameter-side annular portion and the relief of the tapered roller overlap, a radially outer end portion of the recessed groove is located radially outward of a region where an axially inner surface of the large-diameter-side annular portion and the relief of the tapered roller overlap; 2. A tapered roller bearing according to claim 1.

3. the large diameter side end surface of the tapered roller includes an annular surface formed around the relief, Both circumferential end portions of the recessed groove are formed in a region where an axially inner surface of the large diameter side annular portion and the annular surface of the tapered roller overlap.

3. A tapered roller bearing according to claim 2.

4. The recessed groove is formed on the axially inner surface of the large-diameter annular portion from a radially inner end to a radially outer end.

2. A tapered roller bearing according to claim 1.

5. Both circumferential ends of the recessed groove extend substantially linearly in the radial direction.

2. A tapered roller bearing according to claim 1.

6. circumferential end portions of the recessed groove extend so as to approach each other in the circumferential direction from the radially inner side toward the radially outer side.

2. A tapered roller bearing according to claim 1.

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