JP4260581B2 - One-way clutch - Google Patents

Description

  The present invention relates to a one-way clutch for engine braking, which is incorporated in, for example, an engine of a motorcycle.

  In this type of motorcycle engine, there is a conventional one-way clutch on the crankshaft that allows only power transmission from the cell starter to the crankshaft side (see, for example, Patent Document 1 or Patent Document 2). .)

Japanese Utility Model Publication No.59-116639 JP 62-75141 A

  The conventional one-way clutch always operates as a one-way clutch. Therefore, if such a one-way clutch is used for engine braking and only the power transmission from the wheel side to the crankshaft side is allowed, even when the engine is stopped, the rotation of the wheel rotates when the wheel rotates. Transmitted to the shaft. Therefore, in order to handle (push and walk) the vehicle when the engine is stopped, it is necessary to switch the gear to the neutral position and extract the driving force. In the case of a structure without neutral, a new neutral structure had to be incorporated into the gear mission.

In order to solve the conventional problems, an invention according to claim 1, wherein an inner ring and an outer ring which forms the inner race coaxial, the cam surface formed on the outer periphery of the inner ring, between the inner ring and the outer ring A rolling member that is disposed between and rolls on the cam surface; and a biasing member that biases the rolling member in a direction in which the rolling member is constricted by the inner ring and the outer ring along a circumferential direction; A one-way clutch provided with a centrifugal weight pivotably supported by the inner ring and swinging outward by a centrifugal force accompanying the rotation of the inner ring. The centrifugal weight is rocked inward by a tension spring. When the inner ring is stopped, the centrifugal weight swings inward and comes into contact with the rolling member, so that the rolling member moves in the biasing direction. The rolling member is restricted within a range in which the rolling member can freely roll, and a predetermined rotation of the inner ring As described above, the centrifugal weight is arranged so that the restriction of the rolling member within the range in which the rolling member can roll is released by swinging outward and moving away from the rolling member. It is characterized by that.

The invention according to claim 2 is the invention according to claim 1, wherein a plurality of the centrifugal weights are arranged so as to extend along the outer ring, and the centrifugal weight has one end thereof. Are pivotally supported by the inner ring, and have spring receivers for attaching the tension springs in the vicinity of one end and in the vicinity of the other end, respectively. A spring receiver is connected by the tension spring, and the centrifugal weight is biased so as to swing inward, and the centrifugal weight is moved outwardly from the spring receiver near the other end to the rolling member. It has the contact part which contacts, It is characterized by the above-mentioned. According to a third aspect of the invention, in the invention of the second aspect, the contact portion bulges in a circumferential direction with respect to a spring receiver near the other end.

The invention according to claim 1 is configured as described above, and when the inner ring is stopped , the movement of the rolling member in the urging direction is restricted within a range in which the rolling member can roll, and a predetermined inner ring is controlled. Above the rotation speed, a centrifugal weight is provided to release the restriction, so that the rotation is not transmitted to the crankshaft or the like even if the wheel is rotated at a low speed as in the case of handling the vehicle. Therefore, there is no need to perform gear operation or the like when handling the vehicle. Even if the gear mission does not have a neutral mechanism, the vehicle can be routed, so there is no need to provide a neutral mechanism, and the number of parts can be greatly reduced. On the other hand, if the accelerator is returned during traveling, the rotation of the wheel is transmitted to the crankshaft, so that the engine brake can be operated.
In addition, the centrifugal weight is provided with a centrifugal weight, and is pivotally supported by the inner ring so as to swing freely, and is opened outward by centrifugal force at a predetermined rotational speed or more so as to release the restriction. Without using the above, the restriction of the moving range of the rolling member can be canceled by centrifugal force at a predetermined rotational speed or higher. Moreover, the predetermined number of rotations can be arbitrarily selected depending on the weight of the centrifugal weight, and versatility is improved. Furthermore, since a centrifugal force is used, no friction loss occurs.

According to invention of Claim 2, a tension spring can be arrange | positioned inside a rolling member and a one-way clutch can be made compact. According to the invention of claim 3, since the radial width of the centrifugal weight can be reduced, the one-way clutch can be made compact .

  An embodiment according to the present invention will be described below with reference to FIGS. First, FIG. 1 is a longitudinal sectional view of a motorcycle power unit 10 in which an embodiment of the one-way clutch of the present invention is incorporated, and FIG. 2 is the vicinity of a centrifugal start clutch 30 and an engine brake one-way clutch 60 in FIG. It is a figure which expands and shows.

  The power unit 10 is configured by integrating an internal combustion engine 11 and a load-side speed change mechanism 12.

  A crank chamber and a gear chamber are formed inside by combining left and right half case unit 13L and right unit case 13R, in which the crank case of internal combustion engine 11 and the gear case of transmission mechanism 12 are integrated.

  A crankshaft 15 arranged so as to be oriented in the left-right direction of the vehicle is supported on the left and right unit cases 13L, 13R via bearings 16L, 16R. In the internal combustion engine 11, a connecting rod 19 connects a piston 18 slidably fitted in a cylinder bore of a cylinder block 17 and the crankshaft 15.

  A cylinder head 20 joined to the cylinder block 17 forms a combustion chamber 21 between the top surface of the piston 18 and an intake / exhaust valve (not shown) that opens and closes an intake / exhaust port communicating with the combustion chamber 21. ) Is provided. The cam shaft 22 that drives the intake / exhaust valves is rotatably supported by the cylinder head 20 in parallel with the crankshaft 15.

  In the speed change mechanism 12, an input shaft 25 and an output shaft 26 disposed in parallel with the crankshaft 15 are rotatably mounted on the left and right unit cases 13L and 13R. A primary reduction driven gear 25a is fitted to the input shaft 25 at an end protruding rightward from the right unit case 13R, and a drive gear 25b is formed on the left inner side. Further, the output shaft 26 is fitted with a driving sprocket 26a at an end protruding leftward from the left unit case 13L, and a driven gear 26b is fitted inside the rightward side so that the driven gear 26b and the driving gear 26b are driven. The gears 25b mesh with each other.

  A chain 27 is bridged between a drive sprocket 26a projecting outside the output shaft 26 and a driven sprocket integrally provided on the rear wheel of a motorcycle (not shown) to constitute a final reduction mechanism.

  A centrifugal start clutch 30, a torque converter 40, and a primary reduction drive gear 48a are disposed in order from the right end to the inside on the right side of the crankshaft 15 protruding rightward from the right unit case 13R. A primary reduction drive gear 48a meshes with a primary reduction driven gear 25a of the transmission mechanism 12.

  A primary speed reduction mechanism by meshing the primary speed reduction drive gear 48a and the primary speed reduction driven gear 25a, a right side cover 28 that covers the centrifugal start clutch 30 and the torque converter 40 from the right side are provided on the right end surface of the right unit case 13R. Be joined. The right side cover 28 pivotally supports the end of the crankshaft 15 with a bearing 29.

The centrifugal start clutch 30 includes a clutch inner 31 and a clutch outer 35 . The clutch inner 31 includes a disc-shaped inner plate 31a and an inner boss portion 31b that holds the base end thereof. The inner boss portion 31b is splined to the right end portion of the crankshaft 15 and fixed by a clutch tightening nut 32. The crankshaft 15 rotates together with the crankshaft 15.
Clutch weights 34 are pivotally supported by a plurality of support shafts 33 projecting in parallel with the crankshaft 15 on the outer peripheral end side of the inner plate 31a.

The outer plate 35a of the clutch outer 35 has a cylindrical portion covering the plurality of clutch weights 34 with their inner peripheral surfaces facing each other. The outer boss portion 35b that holds the base end of the outer plate 35a is pivotally supported on the crankshaft 15 via a bearing 37 and supported by the inner boss portion 31b via a one-way clutch 60. Has been.

The clutch inner 31 rotates integrally with the rotation of the crankshaft 15, but the rotational torque is not transmitted to the clutch outer 35 by the one-way clutch 60. When the rotational speed of the crankshaft 15 exceeds a predetermined value acts on the outer plate 35a increases the tilting of the clutch weights 34, rotates the clutches outer 35 engages centrifugal type starting clutch 30 is engaged.

  The one-way clutch 60 has a driving force on the transmission mechanism 12 side (clutch outer 35 side) larger than that on the internal combustion engine 11 side (clutch inner 31 side), and the internal combustion engine 11 side (crankshaft 15) rotates. Only when the speed is equal to or higher than a predetermined value, the rotational power can be transmitted from the transmission mechanism 12 side (clutch outer 35 side) to the crankshaft 15 (clutch inner 31 side). Will be described later.

A torque converter 40 disposed adjacent to the right unit case 13R side from the centrifugal start clutch 30 includes a pump impeller 41 integrally coupled to an outer boss portion 35b that holds the base end of the outer plate 35a. The turbine impeller 42 and the stator impeller 43 disposed between the impellers 41 and 42 are arranged.

  A stator boss portion 44 that holds the base end of the stator impeller 43 is spline-fitted to a cylindrical stator shaft 45, and the stator shaft 45 is pivotally supported on the crankshaft 15 via a bearing 46 and mounted on the right unit case 13R. On the other hand, the stator impeller 43 is supported via a freewheel clutch 47, and can rotate in one direction integrally with the stator shaft 45.

  A cylindrical turbine shaft 48 that holds the base end of the turbine impeller 42 is rotatably supported by the stator shaft 45 via a bearing 49, and the primary reduction drive gear is provided at the left end portion of the turbine shaft 48. 48a is formed.

  A side cover 50 that covers the rear surface of the turbine impeller 42 is integrally connected to the pump impeller 41, and a freewheel clutch 51 for transmitting a backload is interposed between the side cover 50 and the turbine shaft 48. ing.

  When the rotational speed of the crankshaft 15 exceeds a predetermined speed, the centrifugal start clutch 30 is engaged, and the pump impeller 41 rotates together with the clutch outer 35, the working oil in the torque converter 40 is moved to the outer periphery of the pump impeller 41. From the side, the turbine impeller 42 and the stator impeller 43 whose rotation is restricted by the free wheel clutch 47 flow in order and circulate back to the inner peripheral side of the pump impeller 41, and the rotational torque of the pump impeller 41 is converted to the turbine. It is transmitted to the impeller 42. Thus, the turbine shaft 48 integrated with the turbine impeller 42, that is, the primary reduction drive gear 48a is rotationally driven.

  When the rotation of the turbine impeller 42 becomes high speed and approaches the speed of the pump impeller 41, the stator impeller 43 is idled by the free wheel clutch 47, and the impellers 41, 42, and 43 are integrated to achieve efficiency as a fluid coupling. Rotate with high. Thus, the torque converter 40 performs an automatic transmission function.

  When the back load during deceleration is input from the speed change mechanism 12 side to the turbine shaft 48 via the primary speed reduction mechanism, the rotational torque is pump impeller 41 via the side cover 50 due to the engagement of the freewheel clutch 51. The rotation of the clutch outer boss portion 35b integral with the pump impeller 41 is transmitted to the crankshaft 15 through the one-way clutch 60, and the engine brake works.

  Next, FIGS. 3 to 6 are views showing members constituting the one-way clutch 60 of the present embodiment, in which FIG. 3 is a retainer, FIG. 4 is a clutch inner ring, and FIG. 5 is a centrifugal weight (regulating member). 6 shows the clutch plate 69, respectively.

  First, FIG. 3A is a right side view of the retainer 61, and FIG. 3B is a cross-sectional view taken along the line BB in FIG. The retainer 61 is an annular plate, and a plurality of outer peripheral portions (3 in the illustrated example) are bent twice to form a spring receiving portion 61a. Further, a portion 61b protruding inward is provided at one location on the inner peripheral portion.

  Next, FIG. 4 (a) is a right side view of the clutch inner ring 62, FIG. 4 (b) is a left side view, and FIG. 4 (c) is a cross-sectional view taken along the line CC in FIGS. 4 (a) and 4 (b). FIG. The clutch inner ring 62 has splines 62a formed on the inner periphery, and cam surfaces 62b formed at a plurality (three in the illustrated example) of the outer periphery. Furthermore, a notch 62c and a pin hole 62d for pivotally mounting a centrifugal weight 63 described later are provided. Further, a plurality of (4 in the illustrated example) shoulder portions 62e extending in the circumferential direction are missing on one surface (left side surface) to form a recess 62f.

  Next, FIG. 5 (a) is a right side view of the centrifugal weight (regulating member) 63, FIG. 5 (b) is a sectional view taken along the line BB of FIG. 5 (a), and FIG. 5 (c) is FIG. ) In FIG. 5C, FIG. 5D is a view in the direction D of FIG. 5A, and FIG. 5E is a view in the direction E of FIG. 5A. The centrifugal weight 63 is formed with a notch 63a and a pin hole 63b for pivotally attaching to the clutch inner ring 62 at one end. In addition, a roller contact portion 63c that contacts a later-described roller 64 when the clutch is idling is formed at the other end portion. At both ends, spring receivers 63d and 63e for attaching a tension spring 68 described later are formed.

  Next, FIG. 6 is a right side view of the clutch plate 69. The clutch plate 69 is an annular flat plate, and is provided with relief portions 69a for disposing tension springs 68 to be described later at a plurality (3 in the illustrated example) of the inner periphery.

  Next, FIG. 7 and FIG. 8 are assembly drawings (right side view) of the one-way clutch 60 of this embodiment, FIG. 7 is a state when the one-way clutch 60 is operating, and FIG. Each state is shown. FIG. 9 is an enlarged view showing only the one-way clutch 60 portion in FIG. 2, and corresponds to a cross section taken along the line IX-IX in FIG.

First, the clutch inner ring 62 having the cam surface 62b formed on the outer periphery is splined to the clutch inner boss portion 31b of the centrifugal start clutch 30 by the spline 62a formed on the inner periphery, and rotates integrally with the crankshaft 15. It is supposed to be. A plurality of (three in the illustrated example) rollers (rolling members) 64 roll on the cam surface 62b of the clutch inner ring 62. 65 is a clutch outer ring formed integrally with the clutch outer boss portion 35b of the centrifugal start clutch 30, and holds the roller 64 in the radial direction between the clutch inner ring 62 and the clutch inner ring 62. They can rotate relative to each other. Reference numeral 66 denotes a compression spring (biasing member) inserted between the spring receiving portion 61a of the retainer 61 and the roller 64, and the roller 64 is moved in the circumferential direction (clockwise in FIGS. 7 and 8). ) Energize.

  7 and 8, the clockwise direction is the normal rotation direction of the engine, and when the clutch outer ring 65 rotates clockwise with respect to the clutch inner ring 62, the roller 64 moves between the clutch inner ring 62 and the clutch outer ring 65. When the clutch inner ring 62 rotates clockwise with respect to the clutch outer ring 65, the above-mentioned narrow pressure is released.

  The above is almost the same as the structure of the conventional one-way clutch, but the one-way clutch 60 of the embodiment of the present invention further has a configuration described below. That is, a plurality of centrifugal weights (restricting members) 63 shown in FIG. 5 (three in the illustrated example) are pivotally attached to the clutch inner ring 62 by pins 67 as shown in FIGS. It can swing. When the centrifugal weight 63 swings inward as shown in FIG. 8, the roller contact portion 63 c at one end of the centrifugal weight 63 contacts the roller 64 and further resists the force of the compression spring 66. 64 is moved counterclockwise in the figure. Further, as shown in FIG. 7, when the centrifugal weight 63 swings outward, the roller contact portion 63 c of the centrifugal weight 63 is separated from the roller 64. Further, a tension spring 68 is attached between the spring receivers 63d and 63e of the adjacent centrifugal weights 63, and urges the centrifugal weights 63 to swing inward.

  When the one-way clutch 60 of this embodiment is assembled, as shown in FIG. 9, a washer 70, a retainer 61, a clutch inner ring 62 (a centrifugal weight 63 and a tension spring) are arranged inside the clutch outer ring 65 from the back. After attaching the roller 64 and the compression spring 66, hold it with the clutch plate 69 and fix it with the circlip 71. At that time, the inward protruding portion 61b (FIG. 3) of the retainer 61 is press-fitted into any one of the four recesses 62f (FIG. 4) of the shoulder 62e formed in the clutch inner ring 62 for positioning.

  When such an engine is started and the crankshaft 15 rotates, the clutch inner 31 of the centrifugal start clutch 30 spline-coupled to the crankshaft 15 also rotates. When the rotational speed reaches a predetermined value, the clutch weight 34 swings around the support shaft 33 by centrifugal force and is pressed against the inner surface of the outer plate 35a of the clutch outer 35, and the clutch outer 35 is rotated by frictional force. Communicated. This rotation is transmitted to the input shaft 25 and the output shaft 26 via the torque converter 40, and finally the wheels of the motorcycle are rotated.

  On the other hand, the rotation of the crankshaft 15 is also transmitted to the clutch inner ring 62 splined to the boss portion 31b of the clutch inner 31, and the clutch inner ring 62 rotates clockwise in FIG. As a result, the cam surface 62b of the clutch inner ring 62 moves toward the relatively lower side, and the inner surface of the clutch outer ring 65 and the cam surface 62b are separated from each other, so that the roller 64 is sandwiched between the inner surface of the clutch outer ring 65 and the cam surface 62b It will never be done. Therefore, the rotation of the crankshaft 15 is not transmitted to the clutch outer 35 of the centrifugal start clutch 30 via the one-way clutch 60.

  Next, when the engine is decelerated during traveling, the rotation of the wheels is transmitted to the clutch outer wheel 65 formed in the clutch outer 35 of the centrifugal start clutch 30. Then, due to the clockwise rotation (FIG. 7) of the clutch outer ring 65 and the urging force of the compression spring 66, the roller 64 moves in the clockwise direction between the inner surface of the clutch outer ring 63 and the cam surface 62b of the clutch inner ring 62. Since the pinching force is applied, the rotation is transmitted to the clutch inner ring 62 by the frictional force and further from the clutch inner boss portion 31b to the crankshaft 15. That is, the engine brake works. In this case, while the crankshaft 15 and the clutch inner 31 are rotating at a predetermined rotation speed or higher (about idling), the centrifugal weight 63 resists the force of the tension spring 68 by centrifugal force as shown in FIG. Since the roller 64 and the roller contact portion 63c of the centrifugal weight 63 are separated from each other, there is nothing to prevent the roller 64 from moving in the clockwise direction in the figure. That is, the roller 64 is released from the restriction within a range that allows rolling, which will be described later.

  Further, when the engine is stopped and the wheels are rotated at a low speed, such as during vehicle handling (push walking), since centrifugal force does not act on the centrifugal weight 63 of the one-way clutch 60, as shown in FIG. The centrifugal weight 63 is swung inward by the force of the tension spring 68. At this time, the roller abutting portion 63c at one end of the centrifugal weight (regulating member) 63 abuts on the roller 64, and further, the roller 64 is moved counterclockwise in the figure against the force of the compression spring 66 to rotate it. Regulate within the movable range. That is, since the roller 64 is released from the clamping pressure between the clutch inner ring 62 and the clutch outer ring 65, the one-way clutch 60 is idled in both directions. Thus, it is possible to push and walk without switching the gear to neutral.

  As described above, in the present embodiment, even if the wheel is rotated at a low speed, the rotation is not transmitted to the crankshaft, so that it is not necessary to perform a gear operation when driving the vehicle. Even if the gear mission does not have a neutral mechanism, the vehicle can be routed, so there is no need to provide a neutral mechanism, and the number of parts can be greatly reduced. On the other hand, if the accelerator is returned during traveling, the rotation of the wheel is transmitted to the crankshaft, and the engine brake can be activated.

  In the present embodiment, since the centrifugal weight 63 is used as the restricting member, the predetermined rotational speed for releasing the restricted state of the one-way clutch 60 can be arbitrarily selected according to the weight of the centrifugal weight 63, and versatility is improved. Further, since this regulating member 63 is operated by centrifugal force, no friction loss occurs.

FIG. 1 is a longitudinal sectional view of a motorcycle power unit 10 in which an embodiment of a one-way clutch according to the present invention is incorporated. FIG. 2 is an enlarged view showing the vicinity of the centrifugal start clutch 30 and the engine brake one-way clutch 60 in FIG. 3 (a) is a right side view of the retainer 61, and FIG. 3 (b) is a cross-sectional view taken along the line BB in FIG. 3 (a). 4 (a) is a right side view of the clutch inner ring 62, FIG. 4 (b) is a left side view, and FIG. 4 (c) is a cross-sectional view taken along the line CC in FIGS. 4 (a) and 4 (b). It is. 5 (a) is a right side view of the centrifugal weight (regulating member) 63, FIG. 5 (b) is a cross-sectional view taken along the line BB of FIG. 5 (a), and FIG. FIG. 5D is a view taken in the direction of arrow C, FIG. 5D is a view taken in the direction of arrow D in FIG. 5A, and FIG. 5E is a view taken in the direction of arrow E in FIG. FIG. 6 is a right side view of the clutch plate 69. 7 and 8 are assembly diagrams (right side view) of the one-way clutch 60 of this embodiment, and FIG. 7 is a diagram showing a state when the one-way clutch 60 is operating. FIG. 8 is also a diagram showing a state when idling in both directions. 9 is an enlarged view showing only the one-way clutch 60 portion in FIG. 2 and corresponds to a cross section taken along the line IX-IX in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Power unit, 11 ... Internal combustion engine, 12 ... Transmission mechanism, 13L ... Left unit case, 13R ... Right unit case, 15 ... Crankshaft, 16L, 16R ... Bearing, 17 ... Cylinder block, 18 ... Piston, 19 ... Connecting rod , 20 ... Cylinder head, 21 ... Combustion chamber, 22 ... Cam shaft, 25 ... Input shaft, 26 ... Output shaft, 27 ... Chain, 28 ... Right side cover, 29 ... Bearing,
30 ... Centrifugal start clutch, 31 ... Clutch inner, 31a ... Inner plate, 31b ... Inner boss, 32 ... Clutch tightening bolt, 33 ... Support shaft, 34 ... Clutch weight, 35 ... Clutch outer, 35a ... Outer plate, 35b … Outer boss, 37… bearing,
40 ... Torque converter, 41 ... Pump impeller, 42 ... Turbine impeller, 43 ... Stator impeller, 44 ... Stator boss, 45 ... Stator boss, 46 ... Bearing, 47 ... Freewheel clutch, 48 ... Turbine shaft, 49 ... Bearings, 50 ... side covers, 51 ... free wheel clutches, 60 ... one-way clutches, 61 ... retainers, 61a ... spring receiving parts, 61b ... inward protruding parts, 62 ... clutch inner rings, 62a ... splines, 62b ... cam surfaces, 62c: Notch, 62d: Pin hole, 62e: Shoulder, 62f: Recess, 63 ... Centrifugal weight (regulating member), 63a ... Notch, 63b ... Pin hole, 63c ... Roller contact part, 63d, 63e ... Spring 64, roller (rolling member), 65 ... clutch outer ring, 66 ... compression spring (biasing member), 67 ... pin, 68 ... tension spring, 69 ... clutch plate, 69a ... relief, 70 ... washer, 71 ... Circlip.

Claims (3)

An inner ring, an outer ring which forms the inner race coaxial, the cam surface formed on the outer periphery of the inner ring, is disposed between the inner ring and the outer ring, and the rolling member rolling on the cam surface In the one-way clutch provided with a biasing member that biases the rolling member in a direction in which the rolling member is narrowly pressed by the inner ring and the outer ring along the circumferential direction,
A centrifugal weight that is pivotally supported by the inner ring and swings outward by a centrifugal force accompanying the rotation of the inner ring,
The centrifugal weight is biased in the direction of swinging inward by a tension spring,
When the inner ring is stopped, the centrifugal weight swings inward and comes into contact with the rolling member, so that the rolling member can roll in the urging direction. In addition to being restricted within the range, the centrifugal weight swings outward at a predetermined rotational speed of the inner ring or more and moves away from the rolling member, so that the rolling member can be rolled. The one-way clutch, wherein the centrifugal weight is arranged so that the restriction is released. The centrifugal weight is of a long and thin shape arranged along the outer ring,
The centrifugal weight has one end pivotally supported by the inner ring, and has a spring receiver for attaching the tension spring in the vicinity of one end and in the vicinity of the other end,
A spring receiver near one end of each of the adjacent centrifugal weights and a spring receiver near the other end are connected by the tension spring, and the centrifugal weight is biased to swing inward,
2. The one-way clutch according to claim 1, wherein the centrifugal weight has an abutting portion that abuts against the rolling member outward from a spring receiver near the other end.   The one-way clutch according to claim 2, wherein the contact portion bulges in a circumferential direction with respect to a spring receiver near the other end.

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