JP2006097771A - One-way clutch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a spring from interfering with a pocket hole when assembling a sprag into the pocket hole of a cage and prevent the spring from coming off the cage easily when assembling the sprag into the pocket hole. <P>SOLUTION: This one-way clutch 1 is provided with the cage 4 provided with a plurality of pocket holes 4a in the circumferential direction, a plurality of sprags 5 held in the pocket holes 4a, and the spring 6 mounted like a circular ring along an inner peripheral face of the cage 4 and energizing the sprag 5 in the direction in which it meshes with an outer ring and an inner ring. Each of both end parts of the spring 6 is locked in the cage 4 by a locking piece 6f to regulate movement in the axial direction of the whole spring 6. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a sprag type one-way clutch used in a power transmission device such as an automatic transmission of an automobile. More specifically, the present invention relates to one of inner and outer rings by tilting movement of a sprag according to the relative rotation of inner and outer rings. The present invention relates to a one-way clutch that transmits the rotational power of the other to the other or interrupts the transmission. In this specification, the state in which the sprags are engaged with the inner and outer rings and the inner and outer rings are connected to rotate integrally and the rotational power is transmitted is referred to as the locked state, and the sprags are released and the rotational power is released. A state in which no signal is transmitted is called a free state.

A conventional sprag type one-way clutch is arranged in an annular space between inner and outer rings. The one-way clutch includes a cage, a sprag, and a spring. The cage includes a plurality of column portions in the circumferential direction, and includes pocket holes between the column portions in the circumferential direction. The sprag is attached to the pocket hole. The spring is guided and attached to the inner peripheral surface of the cage in a state where both ends are overlapped, and urges the sprag in a direction to engage the outer ring and the inner ring (see Patent Document 1).
In the one-way clutch having the above configuration, for example, when the outer ring rotates in the clockwise direction relative to the inner ring, the sprags are engaged with the outer ring and the inner ring, and the inner and outer rings are locked. When the outer ring rotates in the counterclockwise direction relative to the inner ring, the sprag is released from the above-described engagement, and the inner and outer rings are in a free state.

In such a one-way clutch, the spring is unfolded in a straight line in a free state, it is rounded into an annular shape, and both ends are overlapped and attached to the inner peripheral surface of the cage. The fixing force of the spring with respect to the inner peripheral surface of the cage is based on a force that presses the inner peripheral surface of the cage in the diameter-expanding direction in an attempt to expand the spring into a free state. In such a spring, the entire circumferential direction of the spring is pressed against the inner circumferential surface of the cage in the circumferential direction and is relatively difficult to move in the circumferential direction, but is relatively easy to move in the axial direction. It is. Therefore, in the assembly process of the one-way clutch, depending on the direction of the force when the spring is wound around and attached to the inner peripheral surface of the cage, the spring hardly moves in the circumferential direction on the inner peripheral surface of the cage. However, it moves considerably in the axial direction, and the overlapping parts of both ends are inclined obliquely in the circumferential direction, for example, so that the corners (edges) of both ends face the pocket hole and interfere with the pocket hole. There is a fear. In addition, depending on the direction of the force applied when the sprag is assembled into the pocket hole of the cage, the spring may easily move in the axial direction and come off the cage.
JP 2003-130089 A

  Therefore, the problem to be solved by the present invention is that the spring interferes with the pocket hole when the sprag is incorporated into the pocket hole of the cage, and the spring is easily detached from the cage when the sprag is incorporated into the pocket hole. It is to prevent that.

  The one-way clutch according to the present invention biases the retainer having a plurality of pocket holes in the circumferential direction, the plurality of sprags held in the pocket holes, and the direction in which the sprags are engaged with the outer ring and the inner ring. And a spring mounted in an annular shape along the inner peripheral surface of the cage, the springs are engaged with the cage at both ends and the entire spring moves at least in the axial direction. It is characterized by restricting to do.

  The “annular” is not limited to a perfect circular annular shape, and includes an elliptical annular shape and the like.

  In addition, “locking both ends of the spring to the cage and restricting at least the entire spring from moving in the axial direction” means, for example, a locking piece extending at both ends of the spring as a column portion. The movement in the axial direction is almost completely restricted at both ends of the spring as in the case where the movement of the whole spring that is displaced in the axial direction is restricted. Since it is not locked by the stop piece, there is a possibility that it moves slightly in the axial direction.

  Therefore, the present invention includes such a possibility. On the other hand, one or more locking pieces are provided not only at both ends of the spring but also in the middle of the spring so that the entire spring is displaced in the axial direction. It includes a form in which the movement is almost impossible, and as a whole, it means a state where the movement of the spring is restricted by moving in the axial direction.

  According to the present invention, since both ends of the spring are locked in a state in which the movement in the axial direction is restricted by the cage, the entire circumferential direction of the spring is in pressure contact with the inner peripheral surface of the cage. In combination with this, when the sprag is assembled into the pocket hole of the cage, the movement of the spring is restricted in the circumferential direction or the axial direction, so that both ends of the spring are prevented from moving obliquely in the circumferential direction. It is possible to effectively prevent the pocket holes from being interfered with by the edges of these. In the present invention, since both ends of the spring are fixed to the cage in a state in which movement in the axial direction is restricted, when the sprag is incorporated into the pocket hole, the spring is displaced in the axial direction. It is possible to effectively prevent the release from the cage.

  It is preferable to provide hook-shaped locking pieces that are hooked on the pillar portions of the cage and restrict the movement of the entire spring in the axial direction at both ends of the spring. The form of the locking piece may be a hook shape, for example, an L shape opposite to the direction in which the spring end provided with the locking piece extends. It is preferable that the locking piece has the hook shape because the spring can be effectively prevented from moving not only in the axial direction of the entire spring but also in the circumferential direction.

  Furthermore, if hook-like locking pieces are provided not only at both ends of the spring but also at a plurality of locations in the circumferential direction thereof, the movement in the axial direction can be restricted even at the middle of both ends of the spring. It is preferable that the displacement of the entire spring in the circumferential direction and the axial direction can be prevented more effectively.

  Furthermore, the locking piece is constituted by, for example, protrusions in the outer diameter direction provided on a part of the spring, and the protrusions are locked by being fitted into grooves or holes provided corresponding to the cage. May be fixed to the cage.

  According to the present invention, it is possible to prevent the spring from interfering with the pocket hole when the sprag is incorporated into the pocket hole of the cage, and to prevent the spring from being easily detached from the cage when the sprag is incorporated into the pocket hole. can do.

Hereinafter, a one-way clutch according to an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a cross-sectional view showing a structure of a part of a one-way clutch according to an embodiment of the present invention incorporated in an annular space between an outer ring and an inner ring, and FIG. 2 is an annular space between the outer ring and the inner ring. 1 is a perspective view showing the vicinity of both ends of the retainer and spring of the one-way clutch shown in FIG. 1, and FIG. 3 is a view showing the spring expanded on a plane.
With reference to these drawings, the one-way clutch 1 is arranged in an annular space between an outer ring 2 and an inner ring 3. The one-way clutch 1 includes a cage 4, a sprag 5, and a spring 6 as components. The one-way clutch 1 generally includes a sprag 5 accommodated in a pocket hole 4a of the cage 4 when the outer ring 2 rotates in a clockwise direction relative to the inner ring 3. The inner and outer rings 2 and 3 can be integrally rotated by being bitten between the three. On the contrary, when the outer ring 2 rotates counterclockwise relative to the inner ring 3, the sprag 5 tilts in the direction opposite to the biting direction against the elasticity of the spring 6, and the inner / outer ring 2. , 3 interrupts the power transmission.

The components of the one-way clutch 1 outlined above will be described in detail below.
The cage 4 is made of metal or reinforced resin, and a plurality of circumferential column portions 4c are integrally formed between the annular portions 4b and 4b on both sides in the axial direction, and pockets are provided between the circumferential portions of the respective column portions 4c. Hole 4a is formed.

  The sprags 5 are respectively housed and held in the pocket holes 4a, and when the outer ring 2 rotates relative to the inner ring 3 in the clockwise direction, the outer peripheral cam surface 5a becomes the outer ring inner peripheral surface 2a and the inner peripheral cam surface 5b. Is engaged with the outer peripheral surface 3a of the inner ring so that the outer ring 2 and the inner ring 3 are connected to each other so as to be integrally rotatable so that the rotational power of the outer ring 3 is transmitted to the inner ring 2, while the outer ring 2 When relatively rotating in the counterclockwise direction, the above biting is released, the outer ring 2 and the inner ring 3 can be rotated relative to each other, and the outer ring 2 is in a free state in which it rotates idle. Such sprags 5 are held in the pocket holes 4a of the cage 4 in a state where slight tilting in the circumferential direction is allowed.

  The spring 6 is, for example, a thin metal plate that has been quenched and hardened, and is unfolded linearly in a free state. The spring 6 is rolled into an annular shape and stuck to the inner peripheral surface of the cage 4. To be fitted. In the spring 6, a plurality of circumferential column portions 6b are integrally formed between the annular portions 6a on both sides in the axial direction, pockets 6c are formed between the respective column portions 6b, and a tongue piece portion 6d is provided on the column portion 6c. ing. The tongue piece 6d acts on the sprag 5 held in the pocket hole 4a of the cage 4 and urges the sprag 5 to bite the outer ring 2 and the inner ring 3, thereby prestressing in the biting direction. Is granted. When the spring 6 is mounted on the inner peripheral surface of the cage 4, the pocket hole 6 c overlaps the pocket hole 4 a of the cage 4, and the spring 6 is inserted and held in these pocket holes 6 c and 4 a. .

  In the embodiment, one or more axially extending end portions 6e of the spring 6 and two hook-shaped locking pieces 6f in the embodiment are integrally extended in parallel with each other. The locking pieces 6f of the both end portions 6e are respectively in the circumferential direction one side and the other column portions 4c, 4c that define the circumferential inner wall surface of the pocket hole 4a of the retainer 4 to which the both end portions 6e correspond. Are wound in an inverted L shape and locked. The spring 6 is restrained from moving not only in the circumferential direction but also in the axial direction by being hooked and locked so that the locking piece 6f is wound around the column part 4c of the cage 4. Fixed. Since the spring 6 is fixed to the cage 4 in this way, in the one-way clutch 1 of the embodiment, unlike the conventional one, the spring 6 moves in the axial direction when the sprag 5 of the cage 4 is incorporated. Thus, there is no possibility of interfering with the pocket hole 4a of the cage 4. Further, when the sprag 5 is assembled into the pocket hole 4a, the spring 6 does not move in the axial direction and does not come off the inner peripheral surface of the cage 4, so that the assemblability of the sprag 5 is greatly improved.

As shown in FIG. 4, one or more locking pieces 6f are provided not only at both ends but also in the middle of the spring 6, so that the movement of the entire spring 6 in the axial direction is more effective. May be restricted. However, FIG. 4 is a cross-sectional view showing the structure of a one-way clutch according to another embodiment of the present invention, which is shown in a state of being incorporated in an annular space between the outer ring 2 and the inner ring 3. The outer ring 2 and the inner ring 3 are not shown.
In the above, the present invention is not limited to the above-described embodiment, but includes various modifications that do not exceed the scope of the claims.

It is sectional drawing which shows the structure of a part of one-way clutch by embodiment of this invention integrated in the annular space between an outer ring | wheel and an inner ring | wheel. FIG. 2 is a perspective view showing the vicinity of both ends of the one-way clutch retainer and spring of FIG. 1 in a state of being incorporated in an annular space between an outer ring and an inner ring. It is a figure which expand | deploys and shows a spring in a plane. It is sectional drawing which shows the structure of the one-way clutch by other embodiment of this invention shown in the state integrated in the annular space between an outer ring | wheel and an inner ring | wheel.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 One-way clutch 2 Outer ring 3 Inner ring 4 Cage 4a Cage pocket hole 4b Annular part 4c Column part 5 Sprag 6 Spring 6a Annular part 6b Column part 6c Pocket hole 6d Tongue piece part 6f Locking piece

Claims (2)

  A cage having a plurality of pocket holes in the circumferential direction, a plurality of sprags held in the pocket holes, and an inner circumferential surface of the cage so as to bias the sprags in a direction in which the sprags are engaged with the outer ring and the inner ring. In a one-way clutch provided with a spring mounted in an annular shape along with, both ends of the spring are locked to a cage to restrict the entire spring from moving at least in the axial direction. Characteristic one-way clutch. 2. The hook-like locking piece for restricting the movement of the entire spring in the axial direction by being hooked on a pillar portion of the cage is provided at each of both ends of the spring. Direction clutch.

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