JP2017053366A - One-way clutch built-in type pulley device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a one-way clutch built-in type pulley device capable of stabilizing attitude and operation of a roller of a one-way clutch, and capable of improving durability of a leaf spring.SOLUTION: A leaf spring 30 of a one-way clutch 13 includes a base part 31 arranged substantially parallel to an axial core of a roller 17, a pair of folding parts 33 folded inwardly at a first bent part 32 on both ends in a longitudinal direction of the base part 31, and a pair of pressing pieces 35 further folded outward at a second bent part 34 of an inside end part of the pair of folding parts 33. The leaf spring is formed into a symmetrical shape with respect to the longitudinal direction of the base part 31.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a pulley device with a built-in one-way clutch, and more specifically, an input shaft of an auxiliary machine such as an alternator driven by power of an engine crankshaft, or a starter motor that provides power to an engine crankshaft. The present invention relates to a pulley device with a built-in one-way clutch that is used by being fixed to an output shaft or the like.

  In general, a driven pulley is fixed to an end of a rotating shaft of an auxiliary machine for an automobile such as an alternator, and an endless belt is stretched between a driving pulley fixed to an end of an engine crankshaft, It is used to drive the machine. 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 that relative rotation between a pulley and a rotating shaft can be freely performed is known (for example, see Patent Document 1).

  This one-way clutch has a cam surface on the inner ring or the outer ring so as to form a wedge space between the inner ring and the outer ring, and is engaged with and disengaged by a roller (roller) disposed in the wedge space. Repeat the run state. Each roller disposed in the wedge space is accommodated in a plurality of pockets formed in the cage, and is elastic in the direction in which the wedge action is exerted, that is, in the lock direction, by a leaf spring locked to the cage. Pressed.

  The leaf spring is a member formed in a substantially U shape by bending, and has a pair of spring movable portions bent inward in the axial direction at both ends of the base portion of the spring. Further, the leaf spring is locked between the pair of annular portions by being locked by a central spring holding portion and a pair of end side spring holding portions extending radially outward from the pillar portion of the cage. .

JP 2007-198582 A

  By the way, in the pulley device with a built-in one-way clutch described in Patent Document 1, when the leaf spring receives a load from the roller in the overrun state, the spring movable portion is elastically deformed so that the contact point with the roller is The roller moves toward the center in the axial direction, and the roller is supported at a position close to the center in the axial direction, and the posture and movement of the roller may become unstable. Also, if the contact point is set to the outside in the axial direction of the roller to stabilize the movement of the roller, the length of the spring movable part is shortened, so the spring constant increases and the spring force increases with a slight displacement. Therefore, there is a possibility that excessive stress acts on the root R portion of the spring movable portion and breaks, and there is a problem that a large amount of displacement of the roller cannot be taken.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to stabilize the posture and movement of the roller of the one-way clutch and to improve the durability of the leaf spring. An object is to provide a pulley device with a built-in directional clutch.

The above object of the present invention can be achieved by the following constitution.
(1) A sleeve attached to the rotating shaft, a pulley disposed concentrically with the sleeve on the radially outer side of the sleeve, and provided between an outer peripheral surface of the sleeve and an inner peripheral surface of the pulley, and one of the pulley and the sleeve is provided A one-way clutch that transmits rotational force between the pulley and the sleeve when rotating relative to the other in a predetermined direction, and a one-way clutch between the outer peripheral surface of the sleeve and the inner peripheral surface of the pulley. A support bearing provided at a position spaced apart in the axial direction and capable of rotating the pulley and the sleeve while supporting a radial load applied to the pulley, and the one-way clutch includes one of the sleeve and the pulley. A one-way clutch comprising: a cage that rotates together with the member; a plurality of rollers held by the cage; and a plurality of leaf springs that press the plurality of rollers in a direction in which the one-way clutch is engaged. In the type pulley device, the leaf spring includes a base portion disposed substantially parallel to the roller axis, and a pair of folded portions folded inward at first bent portions at both longitudinal ends of the base portion. A pair of pressing pieces that are further folded outward at the second bent portion at the inner end of the pair of folded portions, and are formed in a symmetrical shape in the longitudinal direction of the base portion Pulley device with built-in clutch.
(2) The one-way clutch built-in pulley apparatus according to (1), wherein at least a part of the pair of folded portions of the leaf spring is in close contact with the base.
(3) The one-way clutch built-in pulley apparatus according to (2), wherein when the pressing piece is pressed toward the base by the roller, the contact area between the base and the folded portion decreases.
(4) The one-way clutch built-in pulley device according to any one of (1) to (3), wherein the pressing piece of the leaf spring is formed in an arc shape that is convex in the base direction.
(5) The one-way clutch built-in pulley according to any one of (1) to (4), wherein the base portion and the first bent portion of the leaf spring are supported by a spring holding portion provided in the cage. apparatus.

  According to the present invention, the leaf spring includes a base portion disposed substantially parallel to the roller axis, and a pair of folded portions folded inward at the first bent portions at both longitudinal ends of the base portion, A pair of pressing pieces that are further folded outward at the second bent portion at the inner end of the pair of folded portions, and are formed symmetrically in the longitudinal direction of the base, so that both axial ends of the rollers The vicinity is supported by a pair of pressing pieces, and the posture and movement of the rollers can be stabilized. Moreover, since the length of a press piece can be lengthened, a spring constant can be made small and durability of a leaf | plate spring can be improved.

It is a longitudinal section explaining one embodiment of a pulley device with a built-in one-way clutch according to the present invention. It is an expansion perspective view explaining the holder | retainer of the state which integrated the leaf | plate spring. It is a side view of the leaf | plate spring of FIG. It is a side view explaining the leaf | plate spring of the state which received the load from a roller. It is the perspective view which looked at the 1st modification of a leaf | plate spring from the base side. It is the perspective view which looked at the 1st modification of a leaf spring from the return part side. It is a side view of the 2nd modification of a leaf | plate spring. It is a side view of the 3rd modification of a leaf spring.

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

  As shown in FIG. 1, a pulley device 10 with a built-in one-way clutch according to this embodiment is arranged concentrically with a sleeve 11 attached to a rotating shaft of an engine accessory such as an alternator and radially outside the sleeve 11. Pulley 12. A belt groove 12 a around which a drive belt (not shown) is wound is formed on the outer peripheral surface of the pulley 12.

  A one-way clutch 13 is disposed between the outer peripheral surface of the sleeve 11 in the axial intermediate portion and the inner peripheral surface of the pulley 12 in the axial intermediate portion. A pair of rolling bearings (support bearings) 14 is disposed between the outer peripheral surface at both axial ends of the sleeve 11 and the inner peripheral surface at both axial ends of the pulley 12.

  The one-way clutch 13 transmits a rotational force between the pulley 12 and the sleeve 11 when the pulley 12 rotates relative to the sleeve 11 in a predetermined direction. A deep groove ball bearing or the like is used as the rolling bearing 14 and supports the sleeve 11 and the pulley 12 so as to be capable of relative rotation while supporting a radial load applied to the pulley 12.

  The one-way clutch 13 includes an inner ring 15 that is externally fitted to the outer peripheral surface of the axially intermediate portion of the sleeve 11, an outer ring 16 that is internally fitted to an inner peripheral surface of the axially intermediate portion of the pulley 12, and an outer peripheral surface of the inner ring 15. A plurality of rollers (rollers) 17 rotatably provided in a wedge space between a cam surface 15a formed on the inner surface of the outer ring 16 and a cylindrical surface 16a formed on the inner peripheral surface of the outer ring 16, and a plurality of rollers 17 for individually accommodating each roller 17 And a leaf spring 30 that is supported by the cage 18 and elastically presses each roller 17 in the locking direction.

  As shown in FIG. 2, the retainer 18 includes a pair of annular portions 20 and a plurality of column portions 21 that connect the pair of annular portions 20 in the axial direction.

  Convex portions 20a (see FIG. 1) that engage with both axial end portions of the cam surface 15a are formed on the inner peripheral surfaces of the pair of annular portions 20, and the retainer 18 together with the inner ring 15 and the sleeve 11 are formed. Rotates together.

  In addition, a pair of end-side spring holding portions 22 are arranged in a radial direction from the outer peripheral surface side of each column portion 21 at a portion that is aligned with each column portion 21 in the circumferential direction on the inner side surface in the axial direction of the pair of annular portions 20. It is formed in a state protruding outward. Moreover, the center side spring holding part 23 is formed in the axial direction center part of each pillar part 21 in the state which protrudes from the outer peripheral surface side of each pillar part 21 to radial direction outward. The leaf spring 30 is sandwiched between one circumferential side surface of the end side spring holding portion 22 and the other circumferential side surface of the center side spring holding portion 23. Further, the pair of end portion side spring holding portions 22 covers the radially outer side of the first bent portion 32 of the leaf spring 30 described later, and prevents the leaf spring 30 from coming off in the radial direction.

  As shown in FIGS. 2 and 3, the leaf spring 30 is directed inward by a base portion 31 disposed substantially parallel to the axis of the roller 17 and first bent portions 32 at both longitudinal ends of the base portion 31. A pair of folded portions 33 that are folded back, and a pair of pressing pieces 35 that are further folded outward at the second bent portion 34 at the inner end of the pair of folded portions 33, and in the longitudinal direction of the base portion 31. It is formed symmetrically.

  The folded portion 33 is linearly formed so as to be in close contact with the base portion 31. The second bent portion 34 is curved such that the base side of the pressing piece 35 is separated from the base portion 31, and the pressing piece 35 is inclined so as to be separated from the base portion 31 from the base side toward the distal end side, and is linear. Is formed. The tip of the pressing piece 35 is a roller contact portion 35 a that contacts the roller 17. The leaf spring 30 presses the roller 17 toward the direction in which the one-way clutch 13 is locked, that is, toward the shallow side of the groove of the cam surface 15a by the elastic force generated by the bending of the second bent portion 34. In addition, it is preferable that the roller contact portion 35a of the pressing piece 35 is smoothly rounded or rounded toward the base portion 31 side.

  In the leaf spring 30, the pair of first bent portions 32 are held by the pair of end side spring holding portions 22 of the cage 18, and the center portion of the base portion 31 is the center side spring holding portion 23 of the cage 18. Is held by.

  In the pulley device 10 with a built-in one-way clutch configured as described above, when the one-way clutch 13 is in an overrun state, the pair of pressing pieces 35 of the leaf spring 30 are pressed by the roller 17. Since the roller contact portion 35a supports the vicinity of both end portions in the axial direction of the roller 17, the inclination (skew) of the roller 17 is prevented, and the posture and movement of the roller 17 can be stabilized.

  Further, in the overrun state, the second bent portion 34 and the pressing piece 35 of the leaf spring 30 are elastically deformed toward the base portion 31 side by the pressing force from the roller 17 (see the one-dot chain line in FIG. 4). At this time, the initial contact point A1 between the base portion 31 and the second bent portion 34 moves to the load contact point A2 on the first bent portion 32 side, and the contact area between the base portion 31 and the folded portion 33 decreases. . Thereby, since the length of the 2nd bending part 34 which supports a load increases, the stress which acts on the leaf | plate spring 30 can reduce, and durability of the leaf | plate spring 30 can be improved.

  As described above, according to the pulley apparatus 10 with a built-in one-way clutch of the present embodiment, the leaf spring 30 includes the base portion 31 disposed substantially parallel to the axis of the roller 17 and the longitudinal direction of the base portion 31. A pair of folded portions 33 folded inward at the first bent portions 32 at both ends, and a pair of pressing pieces folded further outward at the second bent portions 34 at the inner end portions of the pair of folded portions 33. 35, and is formed symmetrically in the longitudinal direction of the base 31, so that the vicinity of both ends in the axial direction of the roller 17 is supported by the pair of pressing pieces 35 to stabilize the posture and movement of the roller 17. Can do. Further, since the length of the pressing piece 35 can be increased, the spring constant can be reduced, and the durability of the leaf spring 30 can be improved.

  Further, according to the pulley device 10 with a built-in one-way clutch of the present embodiment, the pair of folded portions 33 of the leaf spring 30 are in close contact with the base portion 31, so that the second bent portion 34 and the pressing piece 35 are elastically deformed by the roller 17. When this is done, the load on the second bent portion 34 can be reduced.

  Further, according to the pulley device 10 with a built-in one-way clutch of the present embodiment, when the roller contact portion 35a of the pressing piece 35 is pressed toward the base 31 by the roller 17, the contact area between the base 31 and the folded portion 33 is increased. Since it decreases, the length of the 2nd bending part 34 which supports a load increases. Thereby, since the stress which acts on the leaf | plate spring 30 reduces, durability of the leaf | plate spring 30 can be improved.

  Further, according to the pulley device 10 with a built-in one-way clutch of the present embodiment, the base portion 31 of the leaf spring 30 and the first bent portions 32 on both sides are connected to the central spring holding portion 23 of the cage 18 and the end portions on both sides. Since each is supported by the spring holding portion 22, the leaf spring 30 can be reliably held.

(First modification)
As a first modification of the present embodiment, as shown in FIGS. 5 and 6, the base portion 31 and the folded portion 33 of the leaf spring 30 may be tightly fixed by a caulking portion 36. Thereby, since the base 31 and the folding | returning part 33 closely_contact | adhere, the movement of the 2nd bending part 34 and the press piece 35 when the press piece 35 is pressed in the base 31 direction by the roller 17 can be stabilized. The effect of reducing the contact area between the base portion 31 and the folded portion 33 can be more reliably exhibited. The fixing of the base 31 and the folded portion 33 is not limited to caulking, and spot welding or the like may be used.

(Second modification)
As a second modification of the present embodiment, the radius of curvature of the first bent portion 32 of the leaf spring 30 may be increased as shown in FIG. Thereby, since the stress applied to the first bent portion 32 at the time of bending the first bent portion 32 can be reduced, the breakage of the first bent portion 32 can be prevented.

(Third Modification)
As a third modification of the present embodiment, as shown in FIG. 8, the pressing piece 35 of the leaf spring 30 may be formed in an arc shape that is convex in the direction of the base 31. Thereby, the change in the contact position between the roller contact portion 35a of the pressing piece 35 and the roller 17 when the second bent portion 34 and the pressing piece 35 are elastically deformed by the roller 17 can be eliminated.

  In addition, this invention is not limited to what was illustrated to the said embodiment, In the range which does not deviate from the summary of this invention, it can change suitably.

10 Pulley device with built-in one-way clutch 11 Sleeve 12 Pulley 13 One-way clutch 14 Rolling bearing (support bearing)
15 Inner ring 16 Outer ring 17 Roller
DESCRIPTION OF SYMBOLS 18 Cage 22 End side spring holding part 23 Center side spring holding part 30 Leaf spring 31 Base part 32 1st bending part 33 Folding part 34 2nd bending part 35 Pressing piece 35a Roller contact part

Claims (5)

A sleeve attached to a rotary shaft; a pulley disposed concentrically with the sleeve on a radially outer side of the sleeve; and provided between an outer peripheral surface of the sleeve and an inner peripheral surface of the pulley, and the pulley and the sleeve Between the outer peripheral surface of the sleeve and the inner peripheral surface of the pulley when one of the two rotates relative to the other in a predetermined direction, and transmits a rotational force between the pulley and the sleeve. A support bearing that is provided at a position axially separated from the one-way clutch, and that allows the pulley and the sleeve to rotate relative to each other while supporting a radial load applied to the pulley.
The one-way clutch includes a cage that rotates together with one member of the sleeve and the pulley, a plurality of rollers held by the cage, and a direction in which the one-way clutch engages the plurality of rollers. A one-way clutch built-in pulley device comprising a plurality of leaf springs pressed against
The leaf spring is
A base disposed substantially parallel to the axis of the roller;
A pair of folded portions folded inward at first bent portions at both longitudinal ends of the base portion;
A pair of pressing pieces that are further folded outwardly at the second bent portion at the inner end of the pair of folded portions,
A pulley device with a built-in one-way clutch, wherein the pulley device has a symmetrical shape in the longitudinal direction of the base portion.   The one-way clutch built-in pulley apparatus according to claim 1, wherein at least a part of the pair of folded portions of the leaf spring is in close contact with the base portion.   The one-way clutch built-in pulley apparatus according to claim 2, wherein when the pressing piece is pressed toward the base by the roller, a contact area between the base and the folded portion decreases.   The one-way clutch built-in pulley apparatus according to any one of claims 1 to 3, wherein the pressing piece of the leaf spring is formed in an arc shape that is convex in the base direction.   The one-way clutch built-in type according to any one of claims 1 to 4, wherein the base portion and the first bent portion of the leaf spring are supported by a spring holding portion provided in the cage. Pulley device.

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