JP2006161847A - One-way clutch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a one-way clutch capable of increasing rigidity and sliding performance of an end bearing, preventing the end bearing from causing abnormal wear and seizure, and reducing racing torque. <P>SOLUTION: A plurality of ribs 15 extending intermittently in the peripheral direction are formed in two rows in the radial direction and in 12 rows at a substantially equal interval in the peripheral direction on an end face on the opposite side to a sprag 3 side in the axial direction of the end bearing 8. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a one-way clutch provided with an end bearing.

  Conventional one-way clutches are described in Japanese Patent Application Laid-Open No. 2002-89590.

  This one-way clutch includes an outer ring, an inner ring, a sprag, a cage, a biasing spring, and an end bearing.

  A plurality of sprags are arranged at substantially equal intervals in the circumferential direction in a state of being held by the retainer between the outer ring and the inner ring. Specifically, the sprag is disposed in the pocket of the cage and is urged in the locking direction by the urging spring.

  The end bearing has a substantially U-shaped axial cross-sectional shape. The said end bearing is arrange | positioned substantially symmetrically with respect to the said sprags in the both sides of the said sprags in the state which orient | assigned the recessed part toward the said sprags. The end bearing slides on the inner peripheral surface of the outer ring or the outer peripheral surface of the inner ring. The end bearing has a slide bearing function.

  A large number of dimples are formed on the end surface of the end bearing in the axial direction opposite to the sprag side.

  The conventional one-way clutch reduces the friction between the end bearing and the member opposite to the sprag side of the end bearing by forming a large number of dimples on the end face, thereby increasing the drag torque of the end bearing. The size is reduced to prevent seizure and abnormal wear of the end bearing, and to reduce idling torque.

  However, in the conventional one-way clutch, since a large number of dimples are formed on the axial end surface (back surface) opposite to the sprag side of the end bearing, the rigidity of the end bearing is reduced. There is a problem that the end bearing is deformed, and friction between the end bearing and the inner and outer rings is increased, so that the performance of the end bearing as a slide bearing is lowered.

In general, in order to avoid the problem of a decrease in the rigidity of the end bearing, if the end bearing is thickened in the axial direction, the axially outer end face of the end bearing and the back side of the end bearing The members are in close contact with each other, and it is difficult to form an oil film between the back surface of the end bearing and the back side member, and there is a problem that seizure of the end bearing and abnormal wear occur.
Japanese Patent Laid-Open No. 2002-89590 (FIG. 1)

  Accordingly, an object of the present invention is to provide a one-way clutch in which the end bearing has high rigidity, the end bearing has high sliding performance, the end bearing does not cause abnormal wear or seizure, and the idling torque is small. is there.

In order to solve the above problems, the one-way clutch of the present invention is
Outer ring,
An inner ring having a lubricating oil supply hole opening on the outer peripheral surface;
An engagement element disposed between the outer ring and the inner ring;
An end bearing disposed between the outer ring and the inner ring and on the outer side in the axial direction with respect to the engagement element,
A rib is formed on the end surface of the end bearing opposite to the engagement side in the axial direction.

  Note that only one end bearing may be arranged on one side in the axial direction with respect to the engaging element, and two end bearings are arranged on the both sides in the axial direction with respect to the engaging element. You may do it.

  According to the present invention, since the rib is formed on the end surface of the end bearing opposite to the axial side of the engagement element, the end bearing can be reinforced with the rib, and the rigidity of the end bearing can be increased. Therefore, the deformation of the end bearing can be prevented, and the sliding performance of the end bearing can be prevented from being lowered.

  Further, according to the present invention, since the end bearing portion that contacts the outer member in the axial direction of the end bearing is only the tip portion of the rib in the axial direction, the end bearing is in the axial direction of the end bearing. There is no close contact with the outer member. Accordingly, a lubricating oil film can be reliably formed between the end surface in the axial direction of the end bearing and the outer member in the axial direction of the end bearing. Therefore, the end bearing and the outer member Thus, seizure and abnormal wear of the end face of the end bearing can be prevented, and idling torque can be reduced.

  According to the above invention, since the lubricating oil supply hole that opens to the outer peripheral surface of the inner ring is formed in the inner ring, the lubricating oil is caused to flow toward the outer peripheral surface side of the inner ring by centrifugal force when the inner ring rotates. It is possible to prevent the one-way clutch from running out of lubricating oil.

  According to the one-way clutch of the present invention, since the rib is formed on the end surface of the end bearing opposite to the axial side of the engagement element, the end bearing can be reinforced with this rib, and the rigidity of the end bearing is increased. it can. Therefore, the deformation of the end bearing can be prevented, and the sliding performance of the end bearing can be prevented from being lowered.

  Further, according to the present invention, since the end bearing portion that contacts the outer member in the axial direction of the end bearing is only the tip portion of the rib in the axial direction, the end bearing is in the axial direction of the end bearing. Without being in close contact with an outer member, seizure and abnormal wear of the end face of the end bearing can be prevented, and idling torque can be reduced.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

(First embodiment)
FIG. 1 is an axial sectional view of a one-way clutch according to a first embodiment of the present invention.

  This one-way clutch includes an outer ring 1, an inner ring 2, a sprag 3 as an example of an engagement element, an outer holder 5, an inner holder 6, a biasing spring 7, and an end bearing 8.

  The outer ring 1 has an inner peripheral cylindrical surface as an engagement surface. The inner ring 2 has an annular recess 10 that opens in the radial direction, and the bottom surface of the annular recess 10 is an outer peripheral cylindrical surface as an engagement surface. The axial width of the bottom surface of the annular recess 10 is substantially the same as the axial width of the inner peripheral cylindrical surface of the outer ring 1.

  The inner ring 2 has a lubricating oil supply hole 12. The lubricating oil supply hole 12 is opened at a portion where the sprag 3 on the outer peripheral surface of the inner ring 2 slides. The lubricating oil supply hole 12 extends along the radial direction of the inner ring 2 and penetrates the inner ring 2. The lubricating oil supply hole 12 is provided to supply lubricating oil from the inner peripheral side of the inner ring 2 to the outer peripheral side. Specifically, when the inner ring 2 rotates, the lubricating oil present on the inner peripheral surface side of the inner ring 2 is automatically moved to the outer peripheral surface side of the inner ring 2 by centrifugal force, and the lubricating oil is moved between the outer ring 1 and the inner ring 2. It is designed to be supplied during

  A plurality of the sprags 3 are arranged at substantially equal intervals in the circumferential direction between the inner peripheral cylindrical surface of the outer ring 1 and the outer peripheral cylindrical surface of the inner ring 2 while being held by the outer retainer 5 and the inner retainer 6. ing. Specifically, the sprag 3 is disposed in the pockets of the outer retainer 5 and the inner retainer 6 and is applied in the locking direction by a biasing spring 7 disposed between the outer retainer 5 and the inner retainer 6. It is energized.

  The end bearing 8 is an annular member having a U-shaped cross section at a portion from the central axis of the axial cross section (half of the axial cross section) and has a radial dimension larger than the depth of the annular recess 10. is doing. The end bearings 8 are arranged substantially symmetrically with respect to the sprags 3 on both sides of the sprags 3 with the recesses facing the sprags 3. The end bearing 8 keeps a predetermined distance between the outer ring 1 and the inner ring 2. Specifically, between the radially outer end surface of the end bearing 8 and the inner circumferential cylindrical surface of the outer ring 1, and the radially inner end surface of the end bearing 8, and the outer circumferential cylindrical surface of the inner ring 2. The end bearing 8 slides on the inner peripheral cylindrical surface of the outer ring 1 and the outer peripheral cylindrical surface of the inner ring 1. The end bearing 8 has a slide bearing function.

  Each of the end bearings 8 has a rib 15 protruding outward in the axial direction on the end surface in the axial direction opposite to the sprag 3 side. The end surface of the rib 15 in the axial direction outer side slides on the side surface 17 of the annular recess 10 of the inner ring 2. A side surface 17 of the annular recess 10 of the inner ring 2 is a receiving surface of the end bearing 8.

  FIG. 2 is a view of the end bearing 8 when viewed from the outside in the axial direction indicated by an arrow A in FIG.

  As shown in FIG. 2, 24 ribs 15 are arranged in two rows in the radial direction and in 12 rows at substantially equal intervals in the circumferential direction. The ribs 15 having the same diameter are substantially the same. Moreover, the inner periphery and outer periphery of the said rib 15 consist of a part of circular arc, and each rib 15 is extended intermittently in the substantially circumferential direction.

  According to the one-way clutch of the first embodiment, since the rib 15 is formed on the end surface 16 opposite to the sprag 3 side in the axial direction of the end bearing 8, the end bearing 8 is reinforced by the rib 15. Thus, the rigidity of the end bearing 8 can be increased. Therefore, the deformation of the end bearing 8 can be prevented, and the sliding performance of the end bearing 8 can be prevented from being lowered.

  Further, according to the one-way clutch of the first embodiment, the portion of the end bearing 8 that contacts the side surface 17 of the annular recess 10 of the inner ring 2 that exists outside the end bearing 8 in the axial direction is formed on the rib 15. Since it is only the tip portion in the axial direction, the end bearing 8 does not come into close contact with the side surface 17 of the annular recess 10 of the inner ring 2. Therefore, a lubricating oil film can be reliably formed between the axially outer end surface of the end bearing 8 and the side surface 17 of the annular recess 10 of the inner ring 2, so that the end bearing 8 and the annular recess 10 of the inner ring 2 are formed. Friction with the side surface 17 can be reduced, seizure and abnormal wear of the axially outer end face of the end bearing 8 can be prevented, and idling torque can be reduced.

  Further, according to the one-way clutch of the first embodiment, since the rib 15 extends in the substantially circumferential direction, the force received from the side surface 17 of the annular recess 10 of the inner ring 2 can be distributed in the circumferential direction, The stress distribution in the end bearing 8 can be made substantially uniform. Therefore, it is possible to prevent the end bearing 8 from being distorted, and to maintain good sliding performance of the end bearing 8 over a long period of time.

  Further, according to the one-way clutch of the first embodiment, since the circumferentially extending ribs 15 are arranged in two rows in the radial direction, the radial gap between the radially arranged ribs 15 A lubricating oil reservoir can be formed at 27, and a lubricating oil film can be formed between the end bearing 8 and the side surface 17 of the annular recess 10 of the inner ring 2. Therefore, friction between the end bearing 8 and the side surface 17 of the annular recess 10 of the inner ring 2 can be further reduced, seizure and abnormal wear of the end bearing 8 can be further prevented, and idling torque can be further reduced.

  In addition, according to the one-way clutch of the first embodiment, since the lubricating oil supply hole 12 that connects the inner peripheral side and the outer peripheral side of the inner ring 2 is formed, the lubrication that exists on the inner peripheral side of the inner ring 2 is formed. The oil can flow to the outer peripheral surface side of the inner ring 2 by centrifugal force when the inner ring 2 rotates. Therefore, it is possible to prevent the one-way clutch from running out of lubricating oil.

  In the one-way clutch of the first embodiment, 24 ribs 15 intermittently extending in the circumferential direction are arranged in two rows in the radial direction and in 12 rows at substantially equal intervals in the circumferential direction. In the one-way clutch of the present invention, the ribs extending intermittently in the circumferential direction may be arranged in an example in the radial direction or a plurality of rows other than the two rows, and the ribs extending intermittently in the circumferential direction are substantially omitted in the circumferential direction. A plurality of rows other than 12 rows may be arranged at equal intervals. Further, a plurality of ribs extending intermittently in the circumferential direction may be arranged in a plurality of rows at non-uniform intervals, and a plurality of ribs extending intermittently in the circumferential direction may be arranged randomly in the radial direction and the circumferential direction. . In the one-way clutch of the present invention, the annular ribs having substantially the same diameter and arranged over the entire circumference in the circumferential direction may be formed in one or more rows in the radial direction.

  Further, in the one-way clutch of the first embodiment, the end bearings having the ribs 15 are disposed on both sides of the sprag 3 approximately symmetrically with respect to the sprags 3. However, the one-way clutch of the present invention has the ribs. The end bearing may be disposed only on one side in the axial direction with respect to the sprag.

  In the one-way clutch of the first embodiment, the member positioned outward in the axial direction of the end bearing 8 is a part of the inner ring 2, but the member positioned outward in the axial direction of the end bearing. However, when the outer ring is other than the inner ring, the outer peripheral surface of the inner ring is more axially outward than the outer end face in the axial direction of the end bearing (the surface on which the rib is formed) and adjacent to the end face. When the opening of the lubricating oil supply hole is formed, a lubricating oil film can be reliably formed between the outer end surface in the axial direction of the end bearing and the member positioned outside, and seizure of the end bearing can be achieved. Abnormal wear can be reliably prevented and idling torque can be further reduced.

(Second Embodiment)
FIG. 3 is a view of the end bearing 38 provided in the one-way clutch of the second embodiment when viewed from the outside in the axial direction.

  The one-way clutch of the second embodiment is different from the one-way clutch of the first embodiment only in the shape of the end bearing 38, and more specifically, the shape of the rib 45 protruding from the axially outer end face of the end bearing 38. Only the one-way clutch is different from the first embodiment.

  In the one-way clutch of the second embodiment, the description of the operation and effect common to the one-way clutch of the first embodiment will be omitted, and only the operation and effect different from those of the one-way clutch of the first embodiment will be omitted. I will explain.

  As shown in FIG. 3, in the second embodiment, the rib 45 has a substantially linear shape. Specifically, twelve ribs 45 are arranged at substantially equal intervals in the circumferential direction, and each rib 45 extends in a substantially radial direction from the inner periphery to the outer periphery.

  According to the one-way clutch of the second embodiment, the rib 45 protruding from the outer end surface in the axial direction of the end bearing 38 extends in the radial direction, so that it greatly affects the sliding performance of the end bearing. The rigidity in the radial direction of the end bearing 38 can be increased, and good sliding performance of the end bearing 38 can be maintained for a long time.

  In the one-way clutch of the second embodiment, twelve ribs 45 extending in the radial direction from the inner periphery to the outer periphery are arranged at substantially equal intervals in the circumferential direction. A plurality of extending ribs other than 12 may be arranged at substantially equal intervals in the circumferential direction. Further, a plurality of ribs extending in the radial direction may be arranged at unequal intervals in the circumferential direction. Further, the rib may not extend from the inner periphery to the outer periphery, and may extend partially in the radial direction between the inner periphery and the outer periphery.

  In the first embodiment, the rib extends in the circumferential direction. In the second embodiment, the rib extends in the radial direction. However, in the one-way clutch according to the present invention, the rib extends in the circumferential direction. The extending rib may be mixed. Further, the rib may extend in any direction other than the circumferential direction and the radial direction. A plurality of hemispherical ribs may be formed. Of course, the shape of the rib is not limited to a linear shape, an arc shape, or a hemispherical shape, and may be any shape such as a wave shape or a polygonal line shape.

It is sectional drawing of the axial direction of the one-way clutch of 1st Embodiment of this invention. It is the figure which looked at the end bearing with which the one-way clutch of the said 1st Embodiment is provided from the axial direction outward. It is the figure which looked at the end bearing with which the one-way clutch of 2nd Embodiment is provided from the axial direction outward.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Outer ring 2 Inner ring 3 Sprag 5 Outer cage 6 Inner cage 7 Biasing spring 8,38 End bearing 12 Lubricating oil supply hole 15,45 Rib 16 End surface of end bearing opposite to sprag side in axial direction 17 Ring of inner ring Side of recess

Claims (1)

Outer ring,
An inner ring having a lubricating oil supply hole opening on the outer peripheral surface;
An engagement element disposed between the outer ring and the inner ring;
An end bearing disposed between the outer ring and the inner ring and on the outer side in the axial direction with respect to the engagement element,
A one-way clutch, characterized in that a rib is formed on an end surface of the end bearing opposite to the engagement side in the axial direction.

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