JP2008064288A - Tapered roller bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tapered roller bearing whose torque can be reduced by reducing the stirring resistance of lubricating oil. <P>SOLUTION: In an axially intermediate portion of at least one of a plurality of peripheral restricting parts 52 of a cage 5, an oil removing passage 53 is formed which is cut out to pass through a region as at least peripherally partial section of the intermediate portion in the radial direction. Thus, lubricating oil smoothly flows out to reduce its stirring resistance. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a tapered roller bearing.

JP 2005-265113 A

  A tapered roller bearing used for an automobile differential or the like is provided with a plurality of tapered rollers held by a cage between an inner ring and an outer ring so that the inner ring and the outer ring can be rotated relative to each other.

  In general, a tapered roller bearing sucks lubricating oil from the small diameter side into the bearing and flows out from the large diameter side by a pumping action generated along with the rolling of the tapered roller. If the lubricating oil flow is not smooth, the agitation resistance increases, and thus there is a problem that the rotational torque increases and the fuel consumption of the vehicle deteriorates. In order to solve this problem, for example, Patent Document 1 discloses a tapered roller bearing in which a lubricant outflow promoting means is provided in the vicinity of the large diameter end of the tapered roller.

  However, even in the above invention, the rotational torque is not sufficiently reduced, and a tapered roller bearing that can further reduce the torque has been desired.

  An object of the present invention is to provide a tapered roller bearing that can reduce the stirring resistance of lubricating oil and can reduce torque.

Means for Solving the Problems and Effects of the Invention

In order to solve the above problems, the tapered roller bearing of the present invention is
An outer ring formed on the inner peripheral surface in such a manner that the outer conical raceway surface that becomes the raceway of the tapered roller that forms the rolling element expands from the second side in the axial direction toward the first side;
An inner conical raceway surface that is arranged concentrically with the outer ring and that forms the raceway of the tapered roller is formed on the outer peripheral surface in a shape that expands from the second side in the axial direction toward the first side, and between the outer ring, An inner ring that is rotatable relative to the outer ring around an axis by the plurality of interposed tapered rollers;
A plurality of pocket portions that are disposed in the rolling element holding space between the outer ring and the inner ring and that respectively accommodate and hold the tapered rollers in a rollable manner are first and second sides in the axial direction of the tapered rollers. Formed by a first axial restricting portion and a second axial restricting portion for restricting the position of the roller, and a plurality of circumferential restricting portions for partitioning each pocket portion in the circumferential direction and restricting the circumferential position of the tapered roller. And at least a part of the circumferential direction restricting portion includes a cage formed by connecting the first axial restricting portion and the second axial restricting portion in the axial direction,
The intermediate portion in the axial direction of at least some of the plurality of circumferential direction restricting portions of the cage is cut out so as to penetrate through the region forming at least a partial section in the circumferential direction of the intermediate portion in the radial direction. In an embodiment, an oil drain passage is formed for guiding the lubricating oil flowing into the rolling element holding space from the second side in the axial direction along with the rolling of the tapered roller from the inner side to the outer side in the radial direction.

  According to the above invention, the retainer of the tapered roller has a plurality of pocket portions formed by the first axial restriction portion, the second axial restriction portion, and the circumferential direction restriction portion, and the tapered rollers are respectively formed in the pocket portions. It is stored and held so that it can roll freely. At least some of the plurality of circumferential direction restricting portions are notched so as to penetrate in a radial direction through an area forming at least a partial section in the circumferential direction of the intermediate portion at an intermediate portion in the axial direction. The oil drain passage is formed. The lubricating oil that has flowed into the rolling element holding space from the small diameter side is guided radially outward through the oil drain passage. Therefore, the lubricating oil can be smoothly discharged toward the large diameter side. As a result, the stirring resistance is reduced and the torque of the tapered roller bearing can be reduced.

  In this case, a part of the plurality of circumferential restriction parts is a connecting pillar part that connects the first axial restriction part and the second axial restriction part, and the remaining circumferential restriction part that does not constitute the connection pillar part. Can be configured such that the oil drain passage is formed in a communication form that connects adjacent pocket portions in the circumferential direction. If it does in this way, a 1st axial control part and a 2nd axial control part will be connected by a connection pillar part, and a maintenance machine will be unified. Further, since the oil drain passage is formed in a communication form that connects adjacent pocket portions in the circumferential direction, the lubricating oil flows out smoothly. Therefore, the stirring resistance is reduced, and the rotational torque of the tapered roller bearing can be further reduced.

  Further, the oil drain passage of the circumferential restriction portion is formed to open to at least one of both circumferential edges of the circumferential restriction portion, and the axial inner edge of the oil drain passage is separated from the opening edge in the circumferential direction. It may be formed in a rounded shape or a tapered shape so as to reduce the passage width. If an edge is formed at the opening in the circumferential edge of the oil drain passage, the tapered roller is likely to be worn.However, by making the inner edge in the axial direction rounded or tapered as described above, such wear is reduced. Can be reduced.

  Further, when the oil drain passage is formed in a communication form, the inner edge in the axial direction of the oil drain passage in the communication form is formed in a convex curve shape so that the passage width of the oil drain passage is minimized at a midway position in the circumferential direction. Can be formed. If it does in this way, abrasion of a tapered roller in the opening part of an oil draining passage can be reduced.

  Furthermore, every fixed number of the plurality of circumferential direction restricting portions can be used as the connecting pillar portion. Thereby, the axial direction strength of the holder can be made uniform over the circumferential direction.

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a partially cutaway perspective view of a tapered roller bearing 1 according to the present invention. As described above, the tapered roller bearing 1 includes the outer ring 2, the inner ring 3 disposed concentrically with the outer ring 2, and the tapered roller 4 interposed between the outer ring 2 and the inner ring 3 while being held by the cage 5. With. The rolling of the tapered roller 4 allows the outer ring 2 and the inner ring 3 to rotate relative to each other around the axis. Further, on the inner peripheral surface of the outer ring 2, an outer conical raceway surface 2a serving as a raceway for the tapered rollers 4 expands from the second side (small diameter side) in the axial direction toward the first side (large diameter side). It is formed with. On the outer peripheral surface of the inner ring 3, an inner conical raceway surface 3a serving as a raceway for the tapered rollers 4 is formed so as to expand in diameter from the second side in the axial direction toward the first side.

  Further, the inner ring 3 is formed with a large collar part 7 and a small collar part 8 protruding in the radial direction so as to be adjacent to the first side and the second side in the axial direction of the inner conical raceway surface 3a. By these large collar part 7 and small collar part 8, the tapered roller 4 is guided to the inner conical raceway surface 3a.

  The cage 5 is disposed in a rolling element holding space between the outer ring 2 and the inner ring 3, and a plurality of pocket portions 51 that respectively accommodate and hold the tapered rollers 4 in a rollable manner are predetermined in the circumferential direction. It is formed at intervals. The pocket portion includes a first axial restricting portion 54 that restricts the position of the tapered roller 4 on the first side in the axial direction, a second axial restricting portion 55 that restricts a position on the second side in the axial direction, and a pocket portion 51. And a plurality of circumferential direction restricting portions 52 that restrict the circumferential position of the tapered roller 4. Further, at least a part of the plurality of circumferential direction restricting portions 52 is formed in such a manner that the first axial restricting portion 54 and the second axial restricting portion 55 are connected in the axial direction. Thereby, separation of the first axial restricting portion 54 and the second axial restricting portion 55 is prevented, and the cage 5 is integrated.

  Further, at least a part of the plurality of circumferential direction regulating portions 52 of the cage is configured to penetrate in a radial direction an area that forms at least a partial section in the circumferential direction of the intermediate part in an intermediate part in the axial direction. The oil drain passage 53 is formed in the form of being cut out. That is, the oil drain passage 53 is formed so as to penetrate the central portion in the radial direction while leaving both ends in the axial direction of the circumferential direction regulating portion 52. The tapered roller 4 is held by both end portions 52 a and 52 b of the circumferential direction regulating portion 52.

  FIG. 2 is a view taken along the line AA in FIG. When the outer ring 2 and the inner ring 3 rotate relative to each other, the tapered roller 4 rolls, and the lubricating oil flows into the rolling element holding space S from the second side (small diameter side) in the axial direction by a pump action associated with centrifugal force. This lubricating oil flows radially outward by centrifugal force. As described above, in the present invention, since the oil drain passage 53 is formed in the circumferential direction restricting portion 52, the lubricating oil can be guided radially outward through the oil drain passage 53, and lubrication is performed from the first axial direction side (large diameter side). It becomes easy to let oil flow out. As a result, the stirring resistance is reduced, and the rotational torque of the tapered roller bearing 1 can be reduced.

  In the conventional tapered roller bearing, since the oil drain passage is not formed in the circumferential restricting portion of the cage, the movement of the lubricating oil in the rolling element holding space is restricted, and the stirring resistance is increased. However, in the present invention, since the oil drain passage 53 is formed as described above, the stirring resistance of the lubricating oil can be reduced.

  FIG. 3 shows a partially enlarged view of the cage 5. In this way, some of the plurality of circumferential direction restriction portions 52 are connected column portions 52 c that connect the first axial restriction portion 54 and the second axial restriction portion 55. The oil drainage passage 53 is formed in a connected form in which the adjacent pocket portion 51 is connected to the remaining circumferential regulating portion 52 in which the connecting pillar portion 52c is not configured. By adopting the connection form in this way, the area of the oil draining portion 53 can be increased, and as a result, the lubricating oil can easily flow out, and the stirring resistance can be further reduced.

  Further, as shown in the drawing, the oil drain passage 53 is not formed in the portion that is the connecting column portion 52c, and the column portion is a complete (not cut out) in order to ensure strength. .

  As shown in the overall view of FIG. 4A, every certain number (here, every three) of the plurality of circumferential direction restricting portions 52 is the connecting pillar portion 52c. In this way, the axial strength of the cage 5 can be made uniform over the circumferential direction. It is preferable to form the connecting column part 52c every three or more. For example, as shown in FIG. In addition, in order to ensure the intensity | strength of the axial direction of the holder | retainer 5, it is desirable to form the connection pillar part 52c at least three places.

  If the oil drain passage 53 is formed, the axial strength of the cage 5 may be reduced. In that case, it is preferable to increase the strength by increasing the thickness of the cage 5.

  The cage 5 can be molded using a synthetic resin. In this case, the synthetic resin is suitably of a type that does not easily deteriorate with respect to the additive of the lubricating oil. For example, polyamide (particularly 6,6-nylon) can be suitably used.

  Returning to FIG. In this embodiment, the oil drain passage 53 is formed to open at both circumferential edges of the circumferential restriction portion 52, and the axial inner edge 57 of the oil drain passage 53 is moved away from the opening edge in the circumferential direction. It is formed in a round shape so as to reduce the width of the passage. More specifically, the axially inner edge 57 of the connected oil drain passage 53 is formed in a convex curved shape so that the passage width of the oil drain passage is minimized at a midway position in the circumferential direction. If it does in this way, abrasion of the tapered roller 4 in an opening part can be reduced. For example, as shown in FIG. 8, it is possible to form the edge E by making the angle between the axial inner edge 57 and the circumferential side edge 56 substantially perpendicular, but this makes the tapered roller 4 easily worn by the edge E. . However, wear can be reduced by making the inner edge 57 in the axial direction round as shown in FIG. The same effect can be obtained if the axial inner edge 57 of the oil drain passage 53 is tapered as shown in FIG.

  Next, another embodiment of the present invention is shown in FIG. In this embodiment, at an intermediate position in the circumferential direction of the circumferential direction restricting portion 52, an intermediate column portion 58 that connects the first axial restricting portion 54 and the second axial restricting portion 55 is left, and an intermediate portion in the axial direction is left. Thus, the oil drain passage 53 is formed in a form in which both side edges in the circumferential direction are cut out so as to penetrate in the radial direction. In this way, the stirring resistance of the lubricating oil can be lowered by the oil drain passage 53 while ensuring the axial strength of the cage 5 by the intermediate column portion 58.

  Moreover, you may make it like FIG. In this embodiment, both circumferential edges of the circumferential restriction portion 52 are left as edge column portions 59 that connect the first axial restriction portion 54 and the second axial restriction portion 55 to the intermediate portion in the axial direction. Thus, the oil drain passage 53 is formed in a form in which the circumferential intermediate portion is cut out so as to penetrate in the radial direction. With this configuration, it is possible to reduce the stirring resistance of the lubricating oil by the oil drain passage 53 while securing the axial strength of the cage 5 by the edge column portion 59.

  As described above, according to the present invention, an area that forms at least a partial section in the circumferential direction of the intermediate portion in an intermediate portion in the axial direction of at least some of the plurality of circumferential restriction portions 52 of the cage. Lubricating oil flowing into the rolling element holding space S from the second side (smaller diameter side) in the axial direction along with the rolling of the tapered roller 4 from the inner side to the outer side in the radial direction. Since the guiding oil drain passage 6 is formed, the lubricating oil can be smoothly discharged to the first side (large diameter side) in the axial direction, and the stirring resistance of the lubricating oil can be lowered. Thereby, the rotational torque of the tapered roller bearing 1 can be reduced, and the fuel efficiency of the vehicle is improved.

1 is a partially cutaway perspective view of a tapered roller bearing according to the present invention. The partial expanded sectional view of a tapered roller bearing. The elements on larger scale of a holder | retainer. (A) Whole side view of a cage. (B) Another example of a cage. The 1st modification of a holder | retainer. The 2nd modification of a holder | retainer. The 3rd modification of a holder | retainer. The 4th modification of a holder | retainer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tapered roller bearing 2 Outer ring 2a Outer conical raceway surface 3 Inner ring 3a Inner conical raceway surface 4 Tapered roller 5 Cage 51 Pocket part 52 Circumferential restriction part 53 Oil drain passage 54 First axial restriction part 55 Second axial restriction part 57 ( Axial inner edge of oil drain passage

Claims (5)

An outer ring formed on the inner peripheral surface in such a manner that the outer conical raceway surface that becomes the raceway of the tapered roller that forms the rolling element expands from the second side in the axial direction toward the first side;
An inner conical raceway surface that is arranged concentrically with the outer ring and that forms the raceway of the tapered roller is formed on the outer peripheral surface in a shape that expands from the second side in the axial direction toward the first side, and between the outer ring, An inner ring that is rotatable relative to the outer ring around an axis by the plurality of interposed tapered rollers;
A plurality of pocket portions that are disposed in the rolling element holding space between the outer ring and the inner ring and that respectively accommodate and hold the tapered rollers in a rollable manner are first and second sides in the axial direction of the tapered rollers. Formed by a first axial restricting portion and a second axial restricting portion for restricting the position of the roller, and a plurality of circumferential restricting portions for partitioning each pocket portion in the circumferential direction and restricting the circumferential position of the tapered roller. And at least a part of the circumferential direction restricting portion includes a cage formed by connecting the first axial restricting portion and the second axial restricting portion in the axial direction,
The intermediate portion in the axial direction of at least some of the plurality of circumferential direction restricting portions of the cage is cut out so as to penetrate through the region forming at least a partial section in the circumferential direction of the intermediate portion in the radial direction. A cone having an oil drainage passage configured to guide the lubricating oil flowing into the rolling element holding space from the second side in the axial direction from the second side in the axial direction to the outer side in the radial direction along with the rolling of the tapered roller. Roller bearing. A part of the plurality of circumferential direction restriction portions is a connecting pillar portion that connects the first axial restriction portion and the second axial restriction portion,
3. The cone according to claim 1, wherein the oil drainage passage is formed in a communication form that connects the adjacent pocket portions in the circumferential direction in the remaining circumferential direction regulation portion that does not constitute the connection column portion. Roller bearing.   The oil drain passage of the circumferential restricting portion is formed to open to at least one of both circumferential edges of the circumferential restricting portion, and an axial inner edge of the oil drain passage is an opening edge in the circumferential direction. The tapered roller bearing according to any one of claims 1 to 3, wherein the tapered roller bearing is formed in a rounded shape or a tapered shape so as to reduce a passage width as it is farther from the center. A tapered roller bearing having the requirements of claim 2,
The tapered roller bearing according to claim 3, wherein the axially inner edge of the oil drain passage in a communication form is formed in a convex curved shape so that the passage width of the oil drain passage is minimized at a midway position in the circumferential direction.   The tapered roller bearing according to any one of claims 2 to 4, wherein a certain number of the plurality of circumferential direction regulating portions are the connecting column portions.

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