JP2008106822A - One-way clutch and one-way clutch built-in pulley apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a one-way clutch and a one-way clutch built-in pulley apparatus to be able to improve the reliability of a clutch function even when starting under a low temperature environment. <P>SOLUTION: The one-way clutch 13 is disposed with a plurality of rollers 22 held in a retainer 23 between a cam surface 20a formed in the outer peripheral surface of a clutch inner ring 20, and a cylindrical track surface 21a formed in the inner peripheral surface of a clutch outer ring 21. The rollers 22 are urged in the lock direction by a spring 24 supported by the retainer 23. The retainer 23 has a pair of rings 25, a plurality of pillars 26 to connect a pair of the rings 25, and center and end supports 28, 29 extending radially outward from the center part and both end parts of the pillar 26. The spring 24 is supported by each side of the center and end supports 28, 29. At least part of radially outer surface 28a of the center support 28 is approximately opposed to a cylindrical track surface 21a of the clutch outer ring 21. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a one-way clutch and a pulley device with a built-in one-way clutch, and more particularly to an input shaft of an auxiliary device such as an alternator driven by power of an engine crankshaft, and conversely, an engine crankshaft. The present invention relates to a one-way clutch used for an output shaft of a starter motor that supplies power to a pulley and a pulley device with a built-in one-way clutch.

  Generally, a driven pulley is fixed to the end of a rotating shaft of an automobile auxiliary machine such as an alternator, and an endless belt is stretched between the crank pulley fixed to the end of the crankshaft of the engine. Is used to drive. In addition, the driven pulley allows the transmission of power from the endless belt to the rotating shaft when the running speed of the endless belt is constant or increases, and the driven pulley is driven when the running speed of the endless belt tends to decrease. 2. Description of the Related Art A pulley device that incorporates a one-way clutch so as to freely rotate a pulley and a rotation shaft is known. Various one-way clutches have been devised for such pulley devices.

  For example, in the one-way clutch 100 shown in FIGS. 4 and 5, a clutch space is formed between the raceway surface of the clutch inner ring 101 and the raceway surface of the clutch outer ring 102 as a cam surface 101a having a plurality of ramp surfaces. The engagement element 103 disposed inside is engaged with and disengaged from both the raceway surfaces to allow power transmission. Further, the engaging element 103 is urged in the locking direction by a spring 105 locked by the cage 104.

The cage 104 includes a pair of ring portions 110, a plurality of column portions 111 that connect the ring portions, and intermediate and end support portions that extend radially outward from the intermediate portion and both end portions of the column portions 111. And the spring 105 is locked by the intermediate and end support portions 112 and 113 (see, for example, Patent Document 1).
JP 2000-240688 A

  By the way, in the conventional one-way clutch 100, as shown in FIG. 4, the cage 104 rotates with the rotation of the clutch inner ring 101, and is deformed and expanded radially outward by centrifugal force. In particular, when the intermediate part of the column part 111 is deformed like a doubly supported beam by centrifugal force, the central support part 112 moves radially outward. As a result, under high speed rotation conditions, the cage 104 may be deformed to a shape that cannot normally hold the spring 105, and the reliability of the function as a one-way clutch may be reduced.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to suppress the deformation of the cage due to centrifugal force, thereby improving the reliability of the clutch function and An object is to provide a one-way clutch built-in type pulley apparatus.

The above object of the present invention can be achieved by the following constitution.
(1) A plurality of engagement elements are arranged in a state of being held by a cage between a cam surface formed on the outer peripheral surface of the inner member and a cylindrical track surface formed on the inner peripheral surface of the outer member. The engagement element is a one-way clutch urged in a locking direction by an elastic member supported by the cage;
The cage includes a pair of annular portions, a plurality of pillar portions connecting the pair of annular portions, and a center portion and end portions extending radially outward from a central portion and both end portions of the pillar portions. A supporting portion, and the elastic member is supported by each side surface of the center and the end supporting portion, and
The one-way clutch according to claim 1, wherein at least a part of a radially outer surface of the central support portion is in close proximity to a cylindrical raceway surface of the outer member.
(2) The outer surface in the radial direction of the central support portion is inclined with respect to the outer surface of the column portion so as to form a wedge-shaped space with the raceway surface of the outer member ( 1-way clutch as described in 1).
(3) The unidirectional according to claim 1 or 2, wherein when a centrifugal force acts on the cage, a radially outer surface of the central support portion protrudes from an outer peripheral surface of the pair of annular portions. clutch.
(4) A one-way clutch built-in type pulley apparatus comprising the one-way clutch according to any one of (1) to (3).

  According to the one-way clutch and the pulley device with a built-in one-way clutch of the present invention, at least a part of the radially outer surface of the central support portion formed in the pillar portion of the cage is formed with the cylindrical raceway surface of the outer member. Since they are close to each other, the center support portion can forcibly suppress the deformation of the cage due to the centrifugal force, and the reliability of the clutch function can be improved.

  In particular, the radial outer surface of the central support portion is inclined with respect to the outer surface of the column portion so as to form a wedge-shaped space between the outer member and the raceway surface. When rotating, grease filled inside enters the wedge-shaped space, and an oil film is generated at a position where the radially outer surface of the central support portion and the raceway surface of the outer member are close to each other, and due to interference with the outer member. Wear of the cage can be prevented. Moreover, since the grease filled therein enters the wedge space, a radially inward force due to the wedge action acts on the central support portion, and deformation of the column portion due to centrifugal force can be suppressed.

  Hereinafter, a one-way clutch and a pulley device with a built-in one-way clutch according to an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a longitudinal sectional view for explaining a pulley device with a built-in one-way clutch for automobile auxiliary equipment according to this embodiment. The one-way clutch built-in pulley apparatus 10 transmits power between an automobile auxiliary machine such as an alternator and a crank pulley fixed to an end portion of an engine crankshaft. As shown in FIG. 1, the pulley apparatus 10 includes a sleeve 11 into which a shaft of an unillustrated automobile auxiliary machine is fitted. Around the sleeve 11, a pulley 12 having a belt groove 12 a formed on the outer peripheral surface is disposed concentrically with the sleeve 11. In addition, a one-way clutch 13 is disposed between the outer peripheral surface of the sleeve 11 and the inner peripheral surface of the pulley 12 in the intermediate portion in the axial direction of the annular space formed therebetween. A pair of support bearings 14 which are ball bearings, such as a deep groove ball bearing, are arrange | positioned at the both ends, ie, the axial direction both sides of the one-way clutch 13, for example. In addition, the shape of the belt groove 12a can be designed in an arbitrary shape such as a V groove, a poly V groove, or a tooth groove.

  The one-way clutch 13 transmits the rotational force from the pulley 12 to the sleeve 11 only when the pulley 12 tends to rotate relative to the sleeve 11 in a predetermined direction. Further, the pair of support bearings 14 enables the relative rotation between the sleeve 11 and the pulley 12 while supporting a radial load applied to the pulley 12.

  Each support bearing 14 includes a bearing inner ring 15 fitted on the outer peripheral surface of the sleeve 11, a bearing outer ring 16 fitted on the inner peripheral surface of the pulley 12, and both raceway surfaces of the bearing inner ring 15 and the bearing outer ring 16. A plurality of balls 17 that are arranged rolling elements, a bearing cage (not shown) that holds the balls 17 in a freely rolling manner, and foreign matter from entering the outside and leakage of lubricant such as grease from the inside. It has a sealing member (not shown) to prevent it.

  As shown in FIGS. 1 and 2, the one-way clutch 13 is press-fitted and fixed to a clutch inner ring 20 that is an inner member that is press-fitted and fixed to the outer peripheral surface of the large-diameter portion of the sleeve 11 and the inner peripheral surface of the pulley 12. A clutch outer ring 21 that is an outer member, and a plurality of rollers 22 that are engaging members rotatably disposed between the clutch inner ring 20 and the clutch outer ring 21 are provided. The outer peripheral surface of the clutch inner ring 20 forms a cam surface in which a plurality of concave ramp surfaces 20a, which are raceway surfaces with which the rollers 22 are brought into rolling contact, are provided at predetermined intervals in the circumferential direction. The roller 22 is rotatably held in a clutch space constituted by each ramp surface 20a and a cylindrical raceway surface 21a formed on the inner peripheral surface of the clutch outer ring 21.

  The one-way clutch 13 engages the retainer 23 having a plurality of pockets for individually holding the rollers 22, and the rollers 22 with the outer peripheral surface of the clutch inner ring 20 and the inner peripheral surface of the clutch outer ring 21. And a spring 24 (see FIG. 2) that is an elastic member that elastically presses in the direction.

  As shown in FIGS. 2 and 3, the cage 23 is arranged at a predetermined interval in the circumferential direction with a pair of annular portions 25 formed at both ends in the axial direction, and connects the pair of annular portions 25. And a plurality of column portions 26 having a predetermined width. A plurality of protrusions 27 are formed radially inward at predetermined intervals in the circumferential direction on the inner peripheral surfaces of the pair of annular portions 25, and the plurality of protrusions 27 are formed on the inner ring 20 of the clutch inner ring 20. The cage 23 is fixed to the clutch inner ring 20 by fitting with the ramp surface 20a. A central support portion 28 extending radially outward is formed at one axial end portion of each column portion 26 in the axial direction, and an axial direction is provided at the other circumferential end portion of each column portion 26. End support portions 29 extending outward in the radial direction are formed at both end portions.

  The radially outer surface 28a of the central support portion 28 is formed to extend radially outward to a position that is close to and opposed to the raceway surface 21a of the clutch outer ring 21, and specifically, the radial height of the end support portion 29 is increased. The height is set to a range equal to or less than the height of the outer peripheral surface of the annular portion 25. In addition, the radially outer surface 28a is inclined in the circumferential direction with respect to the outer surface 26a of the column portion 26 so as to increase in height toward the end support portion side. A wedge-shaped space is formed between the two. In addition, the end support portion 29 has a flange portion 29a that extends toward the center support portion at the radially outer end thereof. The radial outer surface 28a of the central support portion 28 may be linearly inclined in the circumferential direction with respect to the outer surface 26a of the column portion 26, or may be inclined in a curved manner.

  As a result, the spring 24 is configured such that the both ends of the base portion 24a are radially regulated by the flange portions 29a of the end support portion 29 while the base portion 24a is moved between both side surfaces of the center support portion 28 and the end support portion 29. By being pinched, it is supported by the cage 23. And the spring 24 supported in this way presses the roller 22 with the press part 24b formed by bending the both ends of the base 24. FIG.

  In the pulley apparatus 10 with a built-in one-way clutch configured as described above, the roller 22 of the one-way clutch 13 has a wedge action when the rotation angular speed of the pulley 12 is faster than the rotation angular speed of the rotating shaft of an automobile accessory, for example. As a result, the pulley 12 and the sleeve 11 become non-rotatable (locked) relative to each other, so that the rotational force of the engine is reduced by the vehicle. It is transmitted to the rotary shaft of the auxiliary machine. On the other hand, when the rotational angular velocity of the pulley 12 is slower than the rotational angular velocity of the automobile accessory, the engagement of the roller 22 is released, and the relative rotation between the pulley 12 and the sleeve 11 becomes free (overrun state).

  During high-speed rotation, the column portion 26 of the cage 23 is elastically deformed radially outward by centrifugal force, and at the same time, the central support portion 28 formed at the central portion of the column portion 26 also moves radially outward. At this time, the radial outer surface 28a of the central support portion 28 is formed to extend radially outward to a position that is close to and opposed to the raceway surface 21a of the clutch outer ring 21, so that a pair of annular portions is formed by the centrifugal force C. It protrudes from the outer peripheral surface of 25, contacts with the cylindrical raceway surface 21a of the clutch outer ring 21 via the grease, and the deformation of the column portion 26 of the cage 23 can be forcibly suppressed. Further, in the overrun state, the spring 24 is pushed and strokes greatly, but by suppressing the deformation of the column portion 26 of the cage 23, interference between the spring 24 and the column portion 26 of the cage 23 can be suppressed, The retainer 23 can be prevented from being damaged by the spring 24.

  Further, in the overrun state of the one-way clutch 13, the clutch outer ring 21 rotates relative to the clutch inner ring 20 in the direction of arrow A in FIG. 2, and at the same time, the grease enclosed in the clutch space moves in the direction of arrow L. Flowing. The grease flows into a wedge-shaped space between the radial outer surface 28a of the central support portion 28 and the cylindrical raceway surface 21a of the clutch outer ring 21 to generate an oil film therebetween, and the central support portion 28 and the clutch outer ring. Wear due to contact of the raceway surface 21 is prevented. In addition, the grease flowing in the wedge-shaped space can cause the force F to act on the central support portion 28 by the wedge action, and can suppress the deformation of the column portion 26 due to the centrifugal force C.

  As described above, according to the one-way clutch 13 and the pulley device 10 with a built-in one-way clutch configured as described above, at least one of the radial outer surfaces 28a of the central support portion 28 formed on the column portion 26 of the cage 23. Since the portion is in close proximity to the cylindrical raceway surface 21a of the clutch outer ring 21, the center support portion 28 can forcibly suppress deformation of the cage 23 due to the centrifugal force C, and reliability of the clutch function. Can be improved.

  In particular, the radial outer surface 28a of the center support portion 28 is inclined with respect to the outer surface of the column portion 26 so as to form a wedge-shaped space with the raceway surface 21a of the clutch outer ring 21. When the clutch outer ring 21 and the clutch outer ring 21 rotate relative to each other, the grease filled therein enters the wedge-shaped space, and the radial outer surface 28a of the center support portion 28 and the raceway surface 21a of the clutch outer ring 21 are close to each other. An oil film is generated and wear of the cage 23 due to interference with the clutch outer ring 21 can be prevented. Further, since the grease filled therein enters the wedge-shaped space, a force inward in the radial direction due to the wedge action acts on the central support portion 28, and the deformation of the column portion 26 due to the centrifugal force C is suppressed. be able to.

  In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.

  In addition, the one-way clutch of the present invention only needs to transmit a rotational force between the sleeve and the pulley, and the pulley tends to rotate relative to the sleeve in a predetermined direction as in the present embodiment. Only in such a case, a one-way clutch that transmits a rotational force may be used.

  The one-way clutch of the present invention may be a roller clutch as in this embodiment, or may be a cam clutch or a sprag clutch. Further, the outer ring member and inner ring member of the one-way clutch of the present invention may be a clutch outer ring or clutch inner ring formed separately from the pulley or sleeve as in this embodiment, and the inner peripheral surface or sleeve of the pulley. The outer peripheral surface may be constituted by a pulley or a sleeve with a raceway surface.

  Further, the pair of support bearings of the present invention may be of a type other than the deep groove ball bearing, or may be a combination of a roller bearing or a ball bearing. Further, the inner ring or the outer ring of the support bearing may be integrated with the pulley or the sleeve, that is, the inner peripheral surface of the pulley or the outer peripheral surface of the sleeve.

It is a longitudinal cross-sectional view of the one-way clutch built-in pulley apparatus which concerns on one Embodiment of this invention. It is II-II sectional drawing of FIG. It is a perspective view which shows the holder | retainer and spring of a one-way clutch. It is sectional drawing of the conventional one-way clutch. It is a perspective view of the retainer and spring of a conventional one-way clutch.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 One-way clutch built-in pulley apparatus 11 Sleeve 12 Pulley 13 One-way clutch 14 Support bearing 20 Clutch inner ring 21 Clutch outer ring 22 Roller (engagement element)
23 Cage 24 Spring (elastic member)
25 Ring part 26 Column part 28 Center support part 29 End part support part

Claims (4)

A plurality of engagement elements are disposed between the cam surface formed on the outer peripheral surface of the inner member and the cylindrical raceway surface formed on the inner peripheral surface of the outer member, and held by the cage, and The engagement element is a one-way clutch urged in a locking direction by an elastic member supported by the cage,
The cage includes a pair of annular portions, a plurality of pillar portions connecting the pair of annular portions, and a center portion and end portions extending radially outward from a central portion and both end portions of the pillar portions. A supporting portion, and the elastic member is supported by each side surface of the center and the end supporting portion, and
The one-way clutch according to claim 1, wherein at least a part of a radially outer surface of the central support portion is in close proximity to a cylindrical raceway surface of the outer member.   The radial outer surface of the central support portion is inclined with respect to the outer surface of the column portion so as to form a wedge-shaped space with the raceway surface of the outer ring member. One-way clutch as described.   3. The one-way clutch according to claim 1, wherein when a centrifugal force acts on the cage, a radially outer surface of the central support portion protrudes from an outer peripheral surface of the pair of annular portions. A one-way clutch built-in type pulley apparatus comprising the one-way clutch according to claim 1.

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