JP2974928B2 - One-way clutch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a one-way clutch in which a number of sprags are interposed between an outer race and an inner race, and the operation of the sprags transmits torque in one direction.

[0002]

2. Description of the Related Art FIGS. 6 and 7 show a conventional technique. In FIG. 6, reference numeral 1 denotes an outer race attached to a rotating side such as a stator boss, and 2 denotes an inner race attached to a fixed side such as a case. The inner race is arranged at a predetermined pitch in a circumferential direction by a retainer 3 therebetween. A number of sprags 4 are interposed. The retainer 3 is
A sheet metal material is punched and drawn by a press machine to form rectangular window holes 3a at a predetermined pitch in a circumferential direction in a short cylindrical main body, and the outer peripheral end of the sprag 4 is formed by each window hole 3a. Are rotatably fitted and held.

Each of the sprags 4 has a circumferentially extending groove 5 formed on an inner peripheral side thereof. A return spring 6 having a ring shape formed of a coil spring is fitted into the groove 5 so that the sprags 4 are radially outward. And urge it towards you. As shown in FIG. 7, washer-shaped side plates 7 and 8 are arranged on both sides of the retainer 3 and the sprags 4 and fitted between the outer race 1 and the inner race 2, and these outer race 1 and inner race 2 are connected to each other. Is held concentrically.

[0004]

In the prior art, when the outer race 1 rotates leftward in FIG. 6 and each sprag 4 rotates in the engagement direction, that is, leftward rotation, a specific error occurs due to a processing error or the like. When the sprag 4, for example, the center sprag 4a in FIG. 6 rotates in the direction of the arrow (a) earlier than the other sprags 4b, the forward end of the center sprag 4a, that is, the left end 4a-1 is the end of the window hole 3a of the retainer 3. There is a defect that the retainer 3 is damaged by colliding with the edge 3b (rear end).
When a large load is applied to the sprag 4, the sprag 4
The rotation angle in the direction of arrow (a) exceeds a predetermined value, the sprag 4 cannot be returned (rollover), and the function as a one-way clutch is lost. Also, if the pitch of each sprag 4 is increased to reduce the number of sprags 4 as a low load specification model, the return spring 6 is deformed radially outward between the sprags 4 and the appropriate load of the sprags 4 is reduced. However, there were drawbacks such as that it became impossible to maintain.
Furthermore, the sprags 4 are weakly held by the coil springs 6, and the sprags 4 are inadvertently detached from the retainer 3 in the axial direction at the time of assembling. An object of the present invention is to provide a new one-way clutch which has solved the above-mentioned disadvantages.

[0005]

Means for Solving the Problems The present invention is configured as follows to achieve the above object. That is, many sprags between the outer race and the inner race,
In a one-way clutch having a retainer that holds each sprag so as to be able to rotate at a predetermined pitch in a circumferential direction and a return spring that biases each sprag to rotate in an engagement direction,
The front and rear surfaces of the body of the sprag in the circumferential direction are formed in an arc surface centered on the rotation center of the sprag, and the retainer faces a pair of washer-shaped side plates concentrically,
A number of pins are arranged between the side plates at a predetermined pitch in the circumferential direction, and both ends are connected to each side plate. The sprags are interposed in the retainer, and the front and rear surfaces in the circumferential direction are formed. A restricting portion is provided that is brought into contact with the pin, and that when the sprag rotates by a predetermined amount in the engaging direction, the rotating end of the sprag collides with the pin and prevents the sprag from rotating further in the engaging direction. It is configured. Each of the pins has a contact portion projecting forward and backward in the circumferential direction, and a regulating portion projecting in a direction perpendicular to the circumferential direction between the contact portions. It is preferable that the sprags are brought into contact with the front and rear surfaces in the circumferential direction so that when the sprags rotate by a predetermined amount in the engagement direction, the rotating ends of the sprags collide with the regulating portion. In addition, the front and rear surfaces of the body of the sprags, which are slightly more axially than the maximum width in the circumferential direction, are brought into contact with the pins, and each sprag is returned from the outer peripheral side in the axial direction by a ring-shaped return spring. , The sprags may be rotated in the direction of engagement.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a partial cross-sectional side view of a one-way clutch according to an embodiment of the present invention, FIG. 2 is a partial cross-sectional side view in a state where a sprag collides with a restricting portion, and FIG. .
In FIG. 1, A is a one-way clutch in which a number of metallic sprags 12 are interposed between an outer race 10 attached to a rotating side such as a stator boss and an inner race 11 attached to a fixed side such as a case. The sprags 12 are held at a predetermined pitch in the circumferential direction by the retainer 15, and the sprags 12 are urged to rotate in the engagement direction, that is, in the counterclockwise direction (A) in FIG.

Each of the sprags 12 has a front surface 1 of its body.
2a (the left surface in FIG. 1) and the rear surface 12b (the right surface in FIG. 1) are formed as arc surfaces having radii R1 and R2 around the rotation center O1 of the sprag 12, and grooves 13 extending in the circumferential direction to the outer peripheral side. And the bottom surface is at the left end 1
3a (counterclockwise) is inclined such that the right end 13b (clockwise) is radially outward. Further, a collision piece 14 protruding rearward is formed on the inner peripheral portion of each sprag 12. As shown in FIG. 2, when the rotation angle of the collision piece 14 in the engagement direction (the direction of the arrow (a)) of the sprag 12 becomes a predetermined amount, a regulating portion 18 of a rear pin 17 described later. Collide with
This is for preventing further rotation in the arrow (A) direction. In addition, the collision piece 14 is made to protrude forward on the outer peripheral portion of each sprag 12, as shown by a virtual line in FIG.
You may make it collide with the regulation part 18 of the pin 17 of a front part.

Each of the sprags 12 is provided with an outer race 10.
, The height in the radial direction increases when the anti-clockwise rotation (a) is made around the rotation center O1 so that the outer peripheral surface 12c and the inner peripheral surface 12d become the inner periphery of the outer race 10. Surface 10a and outer peripheral surface 11 of inner race 11
When the outer race 10 rotates clockwise (A) around the rotation center O1, the height in the radial direction decreases to rotate the outer race 10 in the clockwise direction (idling direction). The pressure contact engagement with the inner race 11 is released. Then, each of the grooves 1
3 is fitted with a return spring 21 having a ring shape as a coil spring, and the left end 1
At the initial stage, the sprags 12 are rotated counterclockwise (A), that is, in the engagement direction around the rotation center O1 by the reaction force of the return spring 21.

As shown in FIGS. 1 to 3, the retainer 15 has a pair of side plates 16, 16 concentrically facing left and right, and a large number of pins 17 are circumferentially provided between the side plates 16, 16. It is arranged at a predetermined pitch in the direction, and its both ends are connected to the side plates 16, 16. Each of the side plates 16 and 16 is formed by punching a steel plate into a washer shape such that the outer circumference approaches the inner peripheral surface 10a of the outer race 10 and the inner circumference approaches the outer peripheral surface 11a of the inner race 11. Side plate 1
As shown in FIG. 5, a wing nut-shaped pin hole 16a in which small holes are continuously formed on both sides in the circumferential direction of the circular hole at a predetermined pitch in the circumferential direction at the radial center portions of the holes 6 and 16. Dawn.

As shown in FIG. 4, the pin 17 is made of a metal of the same material as that of the sprag 12, and has a column-shaped restricting portion 18 whose upper and lower surfaces are cut off. Is a plate-shaped contact portion 1 formed on an arc surface
9 and 19 are integrally formed, and a locking portion 20 having a step portion 20a is formed at both ends in the longitudinal direction. As shown in FIG. And the step 20a is brought into contact with the inner surface of each of the side plates 16, 16 to maintain the distance between the side plates 16, 16 at a predetermined value.
The two ends are integrally connected by caulking or welding the end of the zero.

As shown in FIG. 1, each of the pins 17 is arranged along the right axis of a locus circle C passing through the rotation center O1 of each sprag 12, and the circumferential interval L1 of the sprag 12 is It is formed slightly smaller than the maximum width L in the circumferential direction of the body, that is, the front and rear surfaces 12a and 12b, and prevents the sprags 12 inserted from the outer peripheral side from coming out in the axial direction. Then, the return spring 21 is fitted into the groove 13 of each sprag 12 from the outer peripheral side, and each sprag 12 is sandwiched by the reaction force of the return spring 21 and the pin 17 to form a unit, and the outer race 10 and the inner race 11 Facilitates assembly between

According to the above embodiment, the front surface 12a and the rear surface 12b of the body of each sprag 12 are formed in an arc surface centered on the rotation center O1 of the sprag 12, and the sprags 12 are arranged in the circumferential direction. Pin 17 to each sprag 12
Are arranged along the trajectory circle C passing through the center of rotation O 1 of the first embodiment, so that the sprags 12 do not attack the retainer 15, that is, the pins 17 even if the sprags 12 rotate irregularly due to a processing error or the like.

When a large load is applied to the sprag 12 and the rotation angle in the engagement direction (the direction of the arrow (a)) becomes a predetermined amount, the collision piece 14 of the sprag 12
Of the sprag 12 is prevented, thereby preventing the sprag 12 from rolling over. When the pitch of each sprag 12 is increased and the number of sprags 12 is reduced as a low-load specification model, the pins 17 support the return springs 21 located between the sprags 12, and the return spring 21 The proper load of each sprag 12, that is, the operation is smoothly maintained.

Further, the inner peripheral side of each sprag 12 is held by a high-strength pin 17, and a return spring 21 is fitted into a groove 13 formed on the outer peripheral side of each sprag 12, and the return spring 21 and the pin 17 And each sprag 1
2 so that each sprag 1
2 does not inadvertently move in the axial direction, and the work of assembling between the outer race 10 and the inner race 11 can be performed easily and quickly.

[0015]

As is apparent from the above description, according to the present invention, the operation becomes smooth and the durability of the retainer is increased. Also, there are effects such as easy attachment of the one-way clutch.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional side view of a one-way clutch showing an embodiment of the present invention.

FIG. 2 is a partial cross-sectional side view of a state where a sprag has collided with a restricting portion.

FIG. 3 is a sectional view taken along line III-III of FIG. 1;

FIG. 4 is a perspective view of a pin showing an embodiment of the present invention.

FIG. 5 is a side view of a main part of a side plate showing an embodiment of the present invention.

FIG. 6 is a sectional side view of a one-way clutch showing a conventional example.

FIG. 7 is a sectional view taken along the line VII-VII of FIG. 6;

[Explanation of symbols]

 A one-way clutch 10 outer race 10a inner peripheral surface 11 inner race 11a outer peripheral surface 12 sprag 12a front surface 12b rear surface 12c outer peripheral surface 12d inner peripheral surface 13 groove 13a left end 13b right end 14 collision piece 15 retainer 16 side plate 16a pin hole 17 pin 18 pin Part 19 Contact part 20 Locking part 20a Step 21 Return spring L, L1, interval O1 Center of rotation C Path circle passing through center of rotation O1

Claims (3)

(57) [Claims] 1. A plurality of sprags between an outer race and an inner race, a retainer for holding each sprag rotatably at a predetermined pitch in a circumferential direction, and a return spring for urging each sprag to rotate in an engagement direction. In the one-way clutch having the sprags, the front and rear surfaces of the body of the sprag in the circumferential direction are formed in an arc surface centered on the rotation center of the sprag, and the retainer faces a pair of washer-shaped side plates concentrically. A large number of pins are arranged at a predetermined pitch in the circumferential direction between the side plates, and both ends of the pins are connected to the side plates. Contact the surface with the pin,
When the sprags rotate by a predetermined amount in the engagement direction, a sprung end of the sprags collides with the pin to prevent a sprag from rotating further in the engagement direction. One-way clutch. 2. Each of the pins has a contact portion projecting forward and rearward in the circumferential direction, and a regulating portion projecting in a direction perpendicular to the circumferential direction between the contact portions. 2. The sprag according to claim 1, wherein the contact portion is brought into contact with the front and rear surfaces of the sprag in the circumferential direction, and when the sprag rotates by a predetermined amount in the engagement direction, the rotating end of the sprag collides with the regulating portion. One-way clutch. 3. The front and rear surfaces of the body of the sprags, which are slightly more axially than the maximum width in the circumferential direction, are brought into contact with the pins, and the sprags are formed from the outer periphery by return springs formed in a ring shape. 3. The one-way clutch according to claim 1, wherein said sprags are pressed in an axial direction to urge the sprags to rotate in an engagement direction.