JP2009008124A - One-way clutch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a one-way clutch having superior quietness and durability. <P>SOLUTION: The one-way clutch 1 is interposed between a PTO output shaft 41 and a PTO transmission shaft 42. A drive-side clutch body 2 is spline-engaged with the PTO output shaft 41. A driven-side clutch body 3 is spline-engaged with the PTO transmission shaft 42. Both the clutch bodies 2, 3 are arranged to oppose each other. A return spring is provided on the outer peripheral face 3b<SB>2</SB>of a boss 3b of the driven-side clutch body 3, and an opposing spring 5 is provided on the inner peripheral face 3b<SB>3</SB>of the boss 3b. During reverse rotation, even if the driven-side clutch body 3 approaches the drive-side clutch body 2, both the clutch bodies 2, 3 do not contact with each other by the resilience of the opposing spring 5. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a one-way clutch suitable for use in a working vehicle such as a tractor, and more particularly to a one-way clutch in which a claw portion is provided on a clutch body on a driving side and a driven side.

  Conventionally, a disk-shaped clutch body is disposed opposite to a drive shaft (drive shaft) and a driven shaft, and a single claw portion is provided on the opposed surface of both clutch bodies, and a bottom portion (opposing end portion) of the claw portion is provided. A one-way clutch is proposed in which a buffer member is disposed between the two (see Patent Document 1).

  The one-way clutch engages the claw portion for power transmission from the drive shaft to the driven shaft and transmits power, and engages the claw portion for power transmission from the driven shaft to the drive shaft. Instead, both clutch bodies are idled so that the clutch is disengaged. The claw portion is provided over substantially the entire circumference of the opposing surface of the clutch body, and has a gently inclined sliding slope. The claw is the opposing surface between the starting end portion and the terminating end portion of the sliding slope. A cushioning member is disposed at the bottom of the part (between the opposed ends).

Japanese Utility Model Publication No. 2-74628

  In the invention of Patent Document 1, when both clutch bodies are idled when the clutch is disengaged, both the claw parts get over each other and the claw part of one clutch body collides with the bottom part of the claw part of the other clutch body. The generated hitting sound has been mitigated by arranging a buffer member at the bottom of the claw.

  However, even if the buffer member is arranged at the bottom of the claw portion as described above, the clutch bodies still repeatedly collide with each other when the clutch is disengaged, so that a constant hitting sound is generated and wear of the buffer member is avoided. I could not. Further, in the case of a one-way clutch having a plurality of claw portions, it is necessary to provide buffer members as many as the number of claw portions, which increases the number of parts and the manufacturing cost.

  Therefore, in the present invention, in addition to the first attaching means that urges the claws of the two clutch bodies to engage with each other, the top of one of the claws of both clutch bodies abuts the bottom of the other claw. It is an object of the present invention to provide a one-way clutch that is also excellent in silence and durability by newly providing second urging means for urging so as not to occur.

According to the first aspect of the present invention, the clutch body (2, 3) is disposed opposite to the drive shaft (41) and the driven shaft (42), and the opposing surfaces (2c) of the clutch bodies (2, 3) are arranged. , 3c) is engaged with the power transmission from the drive shaft (41) to the driven shaft (42) and is disconnected with respect to the power transmission in the reverse direction. In the direction clutch (1),
First biasing means (4) for biasing the claws (10, 11) of the clutch bodies (2, 3) so as to engage with each other;
The top (11b) of one claw (11) of both clutch bodies (2, 3) is against the bottom of the other claw (10) against the urging force of the first urging means (4). And a second urging means (5) for urging not to contact (2c ₁ ),
Even if the clutch bodies (2, 3) are close to each other when the one-way clutch (1) is disengaged, the top portion (11b) of the one claw portion (11) is the bottom portion of the other claw portion (10) ( 2c ₁ ) is configured so as not to contact the one-way clutch.

In the invention according to claim 2, the first urging means (4) and the second urging means (5) are each composed of a coil spring,
The restoring force of the first spring (4) includes the claw portions (10, 11) of the clutch bodies (2, 3) and the bottom portions (2c ₁ , 3c ₁ ) of the claw portions (10, 11). The two clutch bodies (2, 3) are minimized when they approach each other, and are maximized when the top portions (10b, 11b) of the claws (10, 11) of the clutch bodies (2, 3) come into contact with each other. ) In proportion to the distance between
The restoring force of the second spring (5) is minimized when the restoring force of the first spring (4) is maximized, and is maximized when the restoring force of the first spring (4) is minimized. So as to increase or decrease in inverse proportion to the restoring force of the first spring (4),
At the balance position (b) of the restoring force of the first and second springs (4, 5), the top (11b) of the one claw (11) and the bottom (2c) of the other claw (10) ₁ ) and a certain gap (s) is formed between
The one-way clutch according to claim 1.

  According to a third aspect of the present invention, the one-way clutch (1) includes the drive shaft (41) between the PTO power transmission paths (A) for transmitting the power from the engine to the power take-off shaft (43) of the work machine. The first urging means (4) is disposed on the outer peripheral side of the driven side clutch body (3), and is interposed between the driven shaft (42) and the second urging means ( 5) is disposed on the inner peripheral side of the driven clutch body (3), and the first and second urging means (4, 5) are opposed to each other with the driven clutch body (3) interposed therebetween. The one-way clutch according to claim 1, wherein the one-way clutch is formed.

  In addition, although the code | symbol etc. in a parenthesis is for contrast with drawing, it does not have any influence on a claim by this.

According to the first aspect of the present invention, the one-way clutch having the claw portion on the clutch body normally has the clutch bodies close to each other when the clutch body slips over the claw portion at the time of disconnection, and one clutch The top of the claw part of the body and the bottom part of the claw part of the other clutch body were in contact with each other.
In addition to the first urging means for bringing both clutch bodies close to each other in the axial direction, the second urging means for urging both clutch bodies in the direction of separating them in the axial direction is provided, so that the claws are overcome. The contact between the clutch bodies at the time can be eliminated, the noise caused by the hitting sound can be greatly reduced, and the durability of the clutch body can be improved.

  According to the invention of claim 2, the first and second urging means are constituted by coil springs, and the restoring force of the first urging means and the restoring force of the second urging means are: The relationship between the contact points of the clutch bodies is such that a constant gap is formed between the top of the claw part of the one clutch body and the bottom part of the claw part of the other clutch body at the balanced position. It is possible to reduce the hitting sound generated by the above and reduce the wear caused by the sliding between the clutch bodies.

  According to the invention of claim 3, the first urging means is disposed on the outer peripheral side of the driven clutch body, the second urging means is disposed on the inner peripheral side of the driven clutch body, Since the first and second urging means are formed to face each other with the driven clutch body interposed therebetween, it is possible to reduce noise caused by a hitting sound caused by contact between the clutch bodies with a simple structure. At the same time, the durability of the clutch body can be improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIG. 5, the tractor 20 has a traveling machine body 23 supported by front wheels 21 and rear wheels 22, and an engine and a battery 50 are disposed at the front of the traveling machine body 23 by being covered with a bonnet 24. ing. A mission case 31 extends from the lower side to the rear side of the engine, and a steering unit including a steering handle 25 and a driver's seat 26 is provided from the center of the aircraft to the rear.

  A safety frame 28 is provided behind the driver's seat 26, and a three-point link mechanism 29 for attaching the work machine and a PTO shaft (power take-off shaft) 43 for driving the work machine are provided at the rear of the machine body.

  The battery 50 is housed in a recess for battery storage as shown in FIG. 6, and the bottom surface 52 of the recess is biased upward by a spring 53. In addition, a pair of battery holding members 51 and 51, which are plate-like members having a key claw portion 51a, are attached to the upper surface 54 of the concave portion by a spring hinge. The upper surface is always urged downward by the key claw 51a.

  Therefore, the battery 50 is reliably held by the upward biasing force from the above-described bottom surface 52 and the downward biasing force from the battery holding member 51, and the operator holds the battery holding member 51. The battery 50 can be easily attached and detached by opening and closing the hinge 51, and there is no need to remove the holding member fixed by a bolt as in the prior art.

  As shown in FIG. 4, the transmission case 31 includes a transmission shaft 32 for transmitting power from the engine, a hydraulic continuously variable transmission (HST) 33 as a main transmission, an auxiliary transmission 34, and PTO switching. A transmission 30 comprising a device 40 and the like is provided, and the hydraulic continuously variable transmission 33 is branched into a traveling power transmission path B and a PTO power transmission path A to transmit power.

  The traveling power transmission path B transmits power from the engine to the rear wheel drive shaft 22a, and the PTO power transmission path A transmits power from the engine to the PTO shaft 43 for driving the work implement. . The hydraulic continuously variable transmission 33 transmits power to the travel power transmission path B via the travel output gear 35 and transmits power to the PTO power transmission path A via the PTO output shaft (drive shaft) 41. To do.

  The sub-transmission device 34 provided in the travel power transmission path B includes a travel transmission shaft 36 to which rotation is transmitted by the travel output gear 35, and a travel output shaft 37 disposed in parallel to the travel transmission shaft 36. is doing. The travel transmission shaft 36 is provided with three gears 36a, 36b, 36c each having a different number of teeth, the gear 36a is always meshed with the travel output gear 35, and the integrally formed gears 36b, 36c are traveled. The output shaft 37 is configured to selectively mesh with gears 37a and 37b formed to be axially movable.

  The travel output shaft 37 transmits power to the rear wheel drive shaft 22a via a differential gear (not shown) and the like, and a travel power transmission path B is configured.

  On the other hand, the PTO switching device 40 provided in the PTO power transmission path A has a PTO transmission shaft 42 (driven shaft) and a PTO shaft 43 arranged in parallel with the PTO transmission shaft 42, and the PTO transmission shaft 42 is provided. The shaft 42 is connected to the PTO output shaft 41 via the one-way clutch 1 described later.

  The PTO transmission shaft 42 is provided with gears 42a and 42b having different numbers of teeth. The gear 42a is movable in the axial direction and is selectively selected from a gear 43a provided on the PTO shaft 43 through a bearing. It is configured to be able to engage and disengage. The gear 42b is fixedly provided on the PTO transmission shaft 42, and meshes with a gear 43b similarly provided on the PTO shaft 43 via a bearing. Between the gears 43a and 43b of the PTO shaft 43, a shift member 43c that can be selectively engaged and disengaged with respect to the gear 43b is disposed so as to be movable in the axial direction. It is transmitted to the shaft 43, and the PTO power transmission path A is configured.

  Next, the one-way clutch which is the main part of the present invention will be described.

  As described above, the one-way clutch 1 is interposed between the PTO output shaft 41 of the PTO power transmission path A and the PTO transmission shaft 42. As shown in FIG. The clutch body 3 is provided opposite to each other.

Driving-side clutch member 2 is composed of a boss portion 2b of the cylindrical, a disk-shaped clutch portion 2a, the inner diameter of the boss portion 2b is formed inner spline 2b _1, X2 direction of the PTO output shaft 41 The outer spline 41a formed at the end is in spline engagement. Further, a stopper 8 is formed at the inner diameter portion of the clutch portion 2a of the drive side clutch body 2 and at the front end portion of the boss portion to prevent the drive side clutch body 2 from moving in the X1 direction.

On the other hand, the driven side clutch member 3, and a cylindrical boss portion 3b, consists of a disc-shaped clutch portion 3a, the inner diameter of the boss portion 3b internal splines 3b ₁ formed, X1 direction of the PTO transmission shaft 42 The outer spline 42a formed at the end is in spline engagement.

Between the outer peripheral surface (outer peripheral side) 3b ₂ of the boss 3b of the driven side clutch body 3 and the locking member 7 fixed to the PTO transmission shaft 42, a return spring (first urging means) 4 is provided. The driven clutch body 3 is always urged in the X1 direction. Further, an opposing spring (between the locking plate 6 fixed in the X1 axial direction by the snap ring 9 at the X1 end of the PTO transmission shaft 42 and the inner peripheral surface (inner peripheral side) 3b ₃ of the boss member 3b is provided. (Second urging means) 5 is provided, and the driven side clutch body 3 is always urged in the X2 direction.

As shown in FIGS. 2 (a), 2 (b), and 2 (c), a plurality of claw portions 10 and 11 are provided on the opposing surfaces 2c and 3c of the drive side and driven side clutch bodies 2 and 3, respectively. The claw portions 10 and 11 include sliding slopes 10a and 11a, top portions 10b and 11b, and engaging surfaces 10c and 11c, and are opposed to the top portions 10b and 11b of the clutch bodies 2 and 3 on the driving side and the driven side. The bottom portions 3c ₁ and 2c _{1 of the} claw portions 3 and 2 formed on 3c and 2c are configured so as to have a constant gap s as shown in FIG. 2C due to the restoring force of the springs 4 and 5. Has been.

The constant gap s is not formed larger than the height t of the engaging surfaces 10c, 11c of the claw portions 10, 11.
0 <s <t
The gap s is larger than the engagement surfaces 10c and 11c and the one-way clutch 1 cannot be engaged. Further, it is desirable that the clearance s be set in consideration of the swing width caused by the inertia when the two clutch bodies 2 and 3 are close to each other and the power transmission rate of the one-way clutch 1.

  The operation of the one-way clutch according to the present invention will be described below with reference to FIGS.

  For example, when an operator attaches a rotary tiller (work machine) to the PTO shaft 43 and starts work, the engagement surfaces 10c and 11c of the claws 10 and 11 of the one-way clutch 1 are engaged, and both clutch bodies are engaged. 2 and 3 rotate together (when the clutch is engaged), and the power from the engine is transmitted to the work machine via the PTO power transmission path A.

  When the tilling work is finished, the operator raises the work implement before stopping the rotation of the rotary member so that the rotary member does not bite into the soil of the field. When the working machine is lifted, the load on the rotary member from the soil disappears, and an inertial force acts on the rotary member, so that the relative rotation between the PTO transmission shaft 42 and the PTO output shaft 41 is reversed, and the one-way clutch (Hereinafter, the driving clutch body 2 is schematically fixed as shown in FIG. 2, and the direction in which the one-way clutch 1 is engaged is rotated forward, and the direction in which the one-way clutch 1 is disconnected is reversed. Called).

  When the PTO transmission shaft 42 reverses as shown in FIG. 2A, the claw portion 11 of the driven side clutch body 3 starts to climb the sliding slope 10a of the claw portion 10 of the drive side clutch body 2. At this time, the relationship between the restoring force of the return spring 4 and the opposing spring 5 is such that the restoring force of the return spring 4 gradually increases and the restoring force of the opposing spring 5 decreases, as shown in FIG. In this state, the robot moves from position B (balance position) to position C.

  As shown in FIG. 2 (b), the claw portion 11 of the driven clutch body 3 climbs the sliding slope 10a of the claw portion 10 of the drive side clutch body 2, and when it reaches the top portion 10b, the restoring force of the return spring 4 and the opposing spring 5 3 is the position relationship shown in FIG. 3, and the restoring force of the return spring 4 is maximum and the restoring force of the opposing spring 5 is minimum.

  Next, when the claw portion 11 of the driven-side clutch body 3 gets over the claw portion 10 of the driving-side clutch body 2, the claw portion 11 of the driven-side clutch body faces the facing surface 2c of the driving-side clutch body 2. The driven-side clutch body 3 moves closer to the drive-side clutch body 2. At this time, the relationship between the restoring forces of the springs 4 and 5 tends to be a relationship such as the position A shown in FIG. 3, but finally returns to the lower position due to an increase in the restoring force of the opposing spring 5.

Even if the top portion 11b of the driven side clutch body 3 comes close to the opposing surface 2c of the driving side clutch body 2 due to the balance of the restoring forces of the return spring 4 and the opposing spring 5, the top portion 11b of the driven side clutch body 3 and the driving side certain gap s is generated between the bottom 2c ₁ of the claw portion 10 of the clutch body 2, both clutches (2, 3) are not in contact. As described above, the one-way clutch 1 rotates idly without generating a hitting sound due to end surface contact during reverse rotation (when the clutch is disengaged).

Further, by providing the one-way clutch 1 as described above, the top portion 11b of the claw portion 11 of the driven side clutch body 3 and the driving side clutch body are balanced by the restoring force of the return spring 4 and the opposing spring 5. it has become possible to form a gap s between the bottom 2c ₁ of 2 of the claw portion.

  As a result, even if the claw portion 11 of the driven clutch body 3 gets over the claw portion 10 of the drive side clutch body 2 and the both clutch bodies 2 and 3 come close to each other, the clutch bodies 2 and 3 come into contact with each other. There is no (or is buffered), and it has become possible to greatly reduce the hitting sound caused by contact.

Further, the wear of the clutch bodies 2 and 3 due to the contact between the claws 10 and 11 between the clutch bodies 2 and 3 and the bottom portions 3c ₁ and 2c ₁ can be reduced, and the durability of the clutch bodies 2 and 3 can be reduced. It became possible to improve the performance.

  Further, the sliding between the sliding slopes 10a and 11a of both clutch bodies 2 and 3 is reduced, thereby reducing the wear between the sliding slopes 10a and 11a and improving the durability of the further clutch bodies 2 and 3. In addition, since the return spring 4 and the counter spring 5 are disposed to face each other with the passive clutch body 3 interposed therebetween, the one-way clutch can be configured with a simple configuration.

The top view of the one way clutch which concerns on this invention. (A) Explanatory drawing of the claw-type clutch mechanism at the time of climbing on a sliding slope. (B) Explanatory drawing of the claw-type clutch mechanism in the top part. (C) Explanatory drawing of the claw-type clutch mechanism at the time of getting over a claw part. The relationship figure of the restoring force of a return spring and an opposing spring. Sectional drawing of the transmission which concerns on this invention. The side view of the tractor concerning the present invention. The perspective view of a battery attachment part.

Explanation of symbols

1 one-way clutch 2, 3 clutch body (drive side clutch body, driven side clutch body)
2c, 3c facing surface _2c 1, 3c ₁ claw portion bottom 3b ₂ the outer peripheral side of the driven side clutch member (outer peripheral surface)
3b ₃ Inner peripheral side (inner peripheral surface) of the driven clutch body
4 First biasing means (return spring)
5 Second urging means (opposing spring)
10, 11 Claw 20 Tractor 41 Drive shaft (PTO output shaft)
42 Driven shaft (PTO transmission shaft)
43 Power take-off shaft (PTO shaft)
A PTO power transmission path s Gap B Balance position (B position)

Claims (3)

The clutch body is disposed opposite to the drive shaft and the driven shaft, and is engaged with the power transmission from the drive shaft to the driven shaft by the claw portions provided on the opposing surfaces of the both clutch bodies. In a one-way clutch that cuts off the direction of power transmission,
First urging means for urging the claws of the two clutch bodies to engage with each other;
Second urging means for urging the top of one of the claw portions of the two clutch bodies against the urging force of the first urging means so as not to contact the bottom of the other claw portion; With
Even when the two clutch bodies are close to each other when the one-way clutch is disengaged, the top of the one claw is configured not to contact the bottom of the other claw.
A one-way clutch characterized by that. Each of the first urging means and the second urging means comprises a coil spring,
The restoring force of the first spring is minimized when the claws of the two clutch bodies are close to the bottom of the claws, and is maximized when the tops of the claws of the two clutch bodies are in contact. So as to increase or decrease in proportion to the distance between the clutch bodies,
The restoring force of the second spring is minimized when the restoring force of the first spring is maximum, and is maximized when the restoring force of the first spring is minimized. While increasing or decreasing in inverse proportion to the restoring force,
A certain gap is formed between the top of the one claw and the bottom of the other claw at the balance position of the restoring force of the first and second springs.
The one-way clutch according to claim 1. The one-way clutch is interposed between the drive shaft and the driven shaft between PTO power transmission paths that transmit power from the engine to a power take-off shaft of a work machine,
The first urging means is disposed on the outer peripheral side of the driven side clutch body, and the second urging means is disposed on the inner peripheral side of the driven side clutch body,
The first and second urging means are formed to face each other with the driven clutch body interposed therebetween.
The one-way clutch according to claim 1, wherein the one-way clutch.

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