JPH0799180B2 - One way clutch - Google Patents

Description

TECHNICAL FIELD The present invention relates to an improvement of a one-way clutch device used for an engine starting motor or the like.

[Prior Art] As shown in FIG. 5, a conventional one-way clutch device includes rollers 6 arranged in a plurality of wedge-shaped spaces 5 as a connecting means for connecting a clutch outer 3 and a clutch inner 4, respectively. Although the method of pressing with the springs 7 is used, it is necessary to form the holes 8 into which the coil springs 7 are inserted in the clutch outer 3, and it is troublesome to assemble the coil springs 7 and productivity is poor. Will be things.

Therefore, in Japanese Utility Model Publication No. 57-7823, as shown in FIG. 6, engaging portions 6a are formed at both ends of each roller 6 in each wedge-shaped space 5, and each engaging portion 6a of each roller is formed. There is disclosed a method of pressing the roller 6 in the small diameter direction by using the engaged annular coil spring 7.

[Problems to be Solved by the Invention] However, according to Japanese Utility Model Publication No. 57-7823, even if it is not necessary to provide a plurality of holes in the clutch outer, the number of parts is reduced because the engaging portions are attached to both ends of each roller. Since the number of rollers is increased and the length of each roller is shortened only at the engaging portions at both ends of each roller, the contact width between each roller and the clutch outer and the clutch inner is reduced, and as a result, the clutch performance may be deteriorated. .

Further, since the annular coil spring is engaged with each engaging portion, a bending stress is always applied to each engaging portion in the vertical direction, which may adversely affect each engaging portion.

Further, the two coil springs engaged with both ends of each roller must always be balanced with the same pressing force, and when the balance is lost, each roller may tilt and it may be difficult to obtain stable clutch performance. is there.

Further, in the conventional device shown in FIG. 5, in order to downsize the one-way clutch, the spring space 8 (hole for inserting the coil spring 7) needs to be small, and as a result, the coil spring 7 itself. Since the length of the roller becomes short, the roller pressing force becomes small and the clutch performance may deteriorate.

An object of the present invention is to provide a one-way clutch capable of improving clutch performance and downsizing by making the coil spring itself movable.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a wedge-shaped space between a clutch inner and an outer peripheral surface of the clutch inner coaxially arranged on the outer periphery of the clutch inner. A one-way clutch having a clutch outer having a plurality of concave portions forming a, a roller arranged in each wedge-shaped space, and a coil spring for pressing the roller in a narrow direction of the wedge-shaped space, A hole is provided in each of the partition walls of the wedge-shaped space, and the rod-shaped portion protruding from the end turn of the coil spring is inserted into the hole and protrudes into the adjacent wedge-shaped space, and when the roller moves, the roller causes A configuration is adopted in which the rod-shaped portion of the coil spring is pressed.

[Operation] According to the above configuration, the partition wall of each wedge-shaped space is provided with the hole through which the rod-shaped portion protruding from the end turn of the coil spring is inserted, so that the coil spring itself can move in conjunction with the roller. Become.

This will be described with reference to FIG. 3. After the engine rotates by itself, the engine is in an overrun state, and the roller 6 resists the coil spring, as shown in FIG.
The wedge-shaped space 5 moves in the expanding direction (clockwise direction in the drawing). At this time, the coil spring 7 is compressed and the spring elastic force is maximized.

Next, due to the relative position change between the clutch outer 3 and the clutch inner 4 and the pressing force of the coil spring 7, the roller 6 moves in the narrow direction of the wedge-shaped space 5 (counterclockwise direction in the drawing).
In the process of moving to, as shown in FIG. 3- (b), the roller 6 is pressed by the coil spring 7, and the rod-shaped portion 7c protruding from the end turn 7b of the coil spring 7 in the adjacent wedge-shaped space 5 is formed. Contact the terminal 7a. After that, Fig. 3-
As shown in (c), the roller 6 has a coil spring 7
While being pressed by, it moves in a narrow direction of the wedge-shaped space 5 while interlocking with the coil spring 7 while contacting the terminal 7a. As a result, FIG. 3- (b) to FIG. 3- (c)
Up to, the elastic force of the coil spring 7 does not change,
The roller pressing force of the coil spring 7 becomes constant.

EFFECTS OF THE INVENTION As described above, since the roller pressing force of the coil spring becomes constant after the roller abuts on the rod-shaped end of the coil spring in the adjacent wedge-shaped space, the roller is narrowed in the narrow direction of the wedge-shaped space. The roller pressing force of the coil spring does not decrease even at the time of maximum load driving in which the roller is pressed and locked, and it is possible to improve the clutch performance.

Further, the amplitude of the coil spring is from when the roller is positioned in the direction of expansion of the wedge-shaped space to when it comes into contact with the rod-shaped end of the coil spring in the adjacent wedge-shaped space, so compared to the conventional device, The amplitude of the coil spring is reduced. As a result, it is possible to reduce the amplitude stress applied to the coil spring. Further, since the amplitude stress is reduced, the life of the coil spring can be extended and a high quality one-way clutch can be provided.

Further, in the related art, when the one-way clutch is downsized, the length of the coil spring is shortened due to the spring space. Therefore, the pressing force of the roller becomes small, and it is difficult to make the size significantly smaller. However, according to the present invention, even if the one-way clutch is downsized, the interlocking property of the coil spring and the roller does not change, so that the roller pressing force of the coil spring is prevented from decreasing and the amplitude stress applied to the coil spring is reduced. Is possible. As a result, the one-way clutch can be downsized.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

In FIGS. 1 and 2, reference numeral 1 denotes an output shaft of an engine starting motor, which has a stepped tubular shape and is a roller clutch and a one-way clutch 2 that constitutes an overrunning clutch. , But fitted with a helical spline.

The one-way clutch 2 has a clutch outer 3 having a plurality of recesses on the inner circumference thereof, and a clutch inner 4 which is arranged coaxially with the clutch outer 3 and to which the rotational force from the clutch outer 3 is transmitted. .

The plurality of recesses formed on the inner circumference of the clutch outer 3 form a wedge-shaped space 5 with the outer peripheral surface of the clutch inner 4, respectively.

Inside each of the wedge-shaped spaces 5, a roller 6 and a coil spring 7 for pressing the roller 6 in the narrowing direction of the wedge-shaped space 5 (counterclockwise direction in the drawing) are arranged. Note that the roller 6 transfers the rotational force of the clutch outer 3 to the clutch inner 4 by moving in the narrow direction of the wedge-shaped space 5, while the rotation of the clutch inner 4 after the engine self-rotates. When it becomes higher than the rotation of 3, the roller 6 moves in the direction of expansion of the wedge-shaped space 5. As a result, the connection between the clutch outer 3 and the clutch inner 4 is released, and the transmission of the rotational force from the clutch inner 4 to the clutch outer 3 can be cut off.

As shown in FIG. 3, the coil spring 7 has a rod-shaped portion 7c protruding from the end-wound portion 7b of the coil spring 7.
The protrusion 7c is inserted into the hole 8 provided in the partition wall 3b of the wedge-shaped space 5 and protrudes into the adjacent wedge-shaped space 5,
It can move in conjunction with the roller 6.

A pinion 9 is formed at the tip of the clutch inner 4 and is fitted on the output shaft 1 via a bush 13 so as to be rotatable and slidable. The pinion 9 is provided so as to be meshable with a ring gear 14 on the engine crank side.

10 is a washer for preventing the clutch inner 4 from protruding in the axial direction. 11 is a case for accommodating the above-mentioned components forming the one-way clutch 2. Reference numeral 12 denotes an operation lever, which is rotated by electric connection / disconnection of the electric motor, and accordingly moves the one-way clutch 2.

Next, the operation based on the above embodiment will be described.

When the electric motor is energized, the lever 12 is rotated, and the one-way clutch 2 connected to the tip of the lever 12 is pushed to the right in FIG. 2 while being rotated by the action of the helical spline. At this time, in the wedge-shaped space 5 formed by the clutch outer 3 and the clutch inner 4 of the one-way clutch 2, the roller 6 is pressed in the narrow direction in each wedge-shaped space 5 by the elastic force of the coil spring 7. Further, due to the wedge action of the wedge-shaped space 5, the wedge-shaped space 5 is further moved in the narrow direction of the wedge-shaped space 5 and locked, whereby the rotational force of the clutch outer 3 is transmitted to the clutch inner 4 via the roller 6. To be done. Further, a pinion 9 formed at the tip of the clutch inner 4 of the one-way clutch 2
Also, due to the action of the helical spline, it is pushed out while rotating, meshes with the ring gear 14 on the engine crank side, the rotational force of the clutch inner 4 is transmitted to the ring gear 14 via the pinion 9, and the engine is started.

After that, when the engine self-rotates and reaches a predetermined number of revolutions, it becomes an overrun state, and the locked roller 6 resists the elastic force of the coil spring 7 by the action of the centrifugal force and the tapered surface in the wedge-shaped space 5. Then, the wedge-shaped space 5 is moved in the expanding direction (clockwise direction in the drawing). As a result, the connection between the clutch outer 3 and the clutch inner 4 is released, and the pinion 9 idles to prevent the high speed rotation of the engine from being transmitted to the output shaft 1 of the electric motor.

When the rotational force of the clutch outer 3 is transmitted to the clutch inner 4 via the roller 6, the coil spring 7
The rod-shaped portion 7c protruding from the end coil is a partition wall of the wedge-shaped space 5.
Since it is inserted into the hole 8 provided in 3b, the coil spring 7 itself can also move in conjunction with the roller 6.

The operation of the coil spring 7 and the roller 6 at this time is
This will be described with reference to FIG.

After the engine has rotated by itself, the engine is in an overrun state, and the roller 6 moves in the expanding direction of the wedge-shaped space 5 against the coil spring, as shown in FIG. At this time, the coil spring 7 is compressed and the spring elastic force is maximized.

Next, in the process in which the roller 6 moves in the narrow direction of the wedge-shaped space 5 due to the relative position change between the clutch outer 3 and the clutch inner 4 and the pressing force of the coil spring 7, it is shown in FIG. As described above, the roller 6 is pressed by the coil spring 7, and the end of the rod-shaped portion 7c protruding from the end turn 7b of the coil spring 7 in the adjacent wedge-shaped space 5
Contact 7a. Thereafter, as shown in FIG. 3- (c), the roller 6 is pressed by the coil spring 7 while the above-mentioned end is being pressed.
Since it interlocks with the coil spring 7 while contacting 7a,
The spring end turn 7b of the coil spring 7 begins to float above the spring seat 3a, and thereafter, the coil spring 7 is interlocked with the roller 6 until the roller 6 is locked at the time of maximum load driving, and the narrow direction of the wedge-shaped space 5 is reduced. Move to.
As a result, the elastic force of the coil spring 7 does not change and the roller pressing force of the coil spring 7 becomes constant from 3- (b) to FIG. 3- (c).

Next, a second embodiment of the present invention will be described with reference to FIG.

In the second embodiment, by making the tip of the rod-shaped portion 7c protruding from the end turn of each coil spring 7 spiral, the contact state with the roller can be made more accurate, and as a result, The interlock between the coil spring 7 and the roller can be made more reliable.

[Brief description of drawings]

1 is a front sectional view of an essential part of a one-way clutch of the present invention, FIG. 2 is a side sectional view of an embodiment of a one-way clutch of the present invention, and FIG. 3 is an explanatory view of the operation of an essential part of the present invention. FIG. 4 is a perspective view of an essential part of a second embodiment of the present invention, FIGS. 5 and 6 are front sectional views of an essential part of a conventional apparatus, and FIG. 7 is a side view of the roller of FIG. In the figure, 1 ... Output shaft, 2 ... One-way clutch, 3 ... Clutch outer, 3b ... Partition wall, 4 ... Clutch inner, 5
...... Wedge-shaped space, 6 ...... Roller, 7 ...... Coil spring, 7b …… Coil spring end turn, 7c …… Coil spring rod-shaped part, 8 …… Coil spring rod-shaped hole for insertion

Claims (1)

[Claims] 1. A clutch inner, and a clutch outer coaxially arranged on the outer circumference of the clutch inner and having a plurality of recesses each forming a wedge-shaped space between the outer circumference of the clutch inner and the clutch outer. A one-way clutch having a roller arranged in each wedge-shaped space and a coil spring for pressing the roller in a narrow direction of the wedge-shaped space, wherein each partition wall of the wedge-shaped space is provided with a hole, and the coil is formed. The rod-shaped portion of the spring that protrudes from the end turn protrudes into the adjacent wedge-shaped space through the hole, and when the roller moves, the roller presses the rod-shaped portion of the coil spring. One way clutch.