JP5664153B2 - Belt type continuously variable transmission for motorcycles - Google Patents

Description

  The present invention relates to a belt-type continuously variable transmission that changes a gear ratio steplessly by changing the belt winding effective diameter of a drive pulley by the power of a shift actuator.

  In a belt-type continuously variable transmission mounted on a motorcycle or a four-wheeled vehicle, the movable half of a drive pulley is moved in the axial direction by the power of a shift actuator such as a shift electric motor, and the drive pulley There are known ones that change the belt winding effective diameter and change the gear ratio steplessly.

  Among these, in the belt-type continuously variable transmission described in Patent Document 1, a transmission-type electric motor is installed on the upper part of a crankcase in an engine unit (unit swing engine).

JP 2007-55304 A

  In the belt-type continuously variable transmission described in Patent Document 1, the relatively heavy heavy-duty electric motor is installed on the upper part of the crankcase of the engine unit. Steering stability is reduced.

  Further, since the shifting electric motor protrudes from the upper part of the crankcase of the engine unit, it is difficult to effectively use the space above the crankcase.

  An object of the present invention has been made in consideration of the above-described circumstances, and is a belt that can improve the steering stability of the vehicle by setting the position of the center of gravity of the engine unit low, and can effectively use the space above the engine unit. An object is to provide a continuously variable transmission.

The present invention includes a drive pulley that is built in a unit swing type engine unit that is provided with an engine in which a cylinder assembly is tilted forward with respect to a crankcase and is swingably supported by a vehicle body frame, and is driven by the engine. A driven pulley that is rotated via a belt by the drive pulley, and the rotation speed of the driven pulley with respect to the drive pulley is changed by changing the belt winding effective diameter of the drive pulley by the power of the shifting actuator. In the belt type continuously variable transmission for a motorcycle , the shift actuator is located below the cylinder of the cylinder assembly and below the crankshaft of the engine in a side view . It is characterized by being arranged in the front.

  According to the present invention, since the speed change actuator is disposed below the cylinder assembly of the engine in the engine unit and in front of the crankcase of the engine, the speed change actuator is disposed above the crankcase. The position of the center of gravity of the engine unit can be set low, and as a result, the steering stability of the vehicle can be improved. In addition, since the speed change actuator is not disposed above the engine unit, the space above the engine unit can be used effectively.

1 is a left side view showing a scooter type motorcycle including an engine unit to which an embodiment of a belt type continuously variable transmission according to the present invention is applied. FIG. 2 is a left side view showing a vehicle frame and an engine unit of the scooter type motorcycle of FIG. 1. The partial expanded side view which expands and shows the vehicle rear part of FIG. FIG. 4 is a partial cut side view showing a left side portion of the body frame or the like in FIG. The left view which shows the engine unit of FIG. Sectional drawing which follows the VI-VI line of FIG. The partial expanded sectional view which expands and shows a part of FIG.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. However, the present invention is not limited to this embodiment. FIG. 1 is a left side view showing a scooter type motorcycle to which an embodiment of a belt type continuously variable transmission according to the present invention is applied. FIG. 2 is a left side view showing a vehicle body frame and an engine unit of the scooter type motorcycle of FIG. In this embodiment, front / rear, left / right, and upper / lower expressions are based on the driver at the time of boarding the vehicle.

  The scooter type motorcycle 10 of this embodiment is a large scooter for two people. The vehicle body front portion 11 of the scooter type motorcycle 10 includes a leg shield 12, a screen 13, and a handle bar 14 that project left and right. The handle bar 14 is rotatably connected to a steering shaft 17 pivotally supported by the head pipe 16 of the vehicle body frame 15 shown in FIG. A front wheel 19 is suspended from the steering shaft 17 via a pair of left and right front forks 18. When the steering shaft 17 is pivotally supported by the head pipe 16 so as to be able to turn left and right, the front wheel 19 is turned left and right by the operation of the handle bar 14.

  As shown in FIG. 1, in the scooter type motorcycle 10, a double seat 20 for two persons is disposed behind the vehicle body front portion 11. A pair of left and right plate-like footboards 21 on which the occupants (drivers and passengers) seated on the double seat 20 can place both feet in a range from the vehicle body front portion 11 to the double seat 20 are provided. A center tunnel 22 that extends and bulges upward is formed between the footboards 21.

  Further, a rear cover 23 that covers the rear portion of the vehicle body is provided below the double seat 20. Below the rear cover 23, a unit swing type engine unit 25 that drives the rear wheel 24 is mounted on the vehicle body frame 15 shown in FIG.

  Here, the vehicle body frame 15 includes the head pipe 16 at a front end portion, and a pair of left and right down tubes 26 and 27 extend downward from the lower and upper portions of the head pipe 16, respectively. The front down tube 26 is formed with a lower portion bent backward, and a pair of left and right lower tubes 29 are connected to the lower end portion. Further, a pair of left and right main tubes 28 extend rearward from a substantially central position in the vertical direction of the front down tube 26. The lower end portion of the rear down tube 27 is connected to the main tube 28 and the rear portion of the lower tube 29 is also connected. Further, a seat rail 30 extending rearward is connected to the rear portion of the lower tube 29.

A pair of left and right main tubes 28 and lower tubes 29 that are spaced apart from each other in the vehicle width direction are bridged. The main tube 28 and the lower tube 29 support the double seat 20. Bridges 31 and 32 are respectively installed. Further, a suspension plate 38 is fixed at the intersection of the main tube 28 and the seat rail 30.

  As shown in FIGS. 3 and 5, the engine unit 25 includes a crankcase 33 that houses a crankshaft 75, and a cylinder assembly 34 that is inclined forward with respect to the crankcase 33. The power transmission device 36 is integrated with the engine 35. The cylinder assembly 34 includes a cylinder 40, a cylinder head 41, and a head cover 42 that are sequentially stacked from the crankcase 33 side. Further, the power transmission device 36 includes a belt-type continuously variable transmission 37 (FIG. 6) described later in a belt case 70 that is provided on the left side of the crankcase 33 of the engine 35 and extends rearward. The rotational force of the crankshaft 75 in the engine 35 is shifted by the power transmission device 36 (belt type continuously variable transmission 37) and transmitted to the rear wheels 24.

  A pair of left and right bearing bosses 43 are provided on the upper part of the crankcase 33 so as to protrude upward. As shown in FIGS. 3 and 4, an engine suspension bracket 45 is pivotally supported on the suspension plate 38 of the vehicle body frame 15 using an engine suspension bolt 44. A bearing boss 43 of the engine unit 25 is rotatably connected to the engine suspension bracket 45 using a pivot shaft 46. As described above, the engine unit 25 is supported (supported) so as to be swingable in the vertical direction with respect to the vehicle body frame 15 around the pivot shaft 46 provided in the bearing boss 43 at the upper part of the engine unit 25.

  As shown in FIGS. 3 and 4, the lower front portion of the crankcase 33 in the engine unit 25 is buffered to the vehicle body frame 15 (lower tube 29) by a cushion unit (rear shock absorber) 48 via a link mechanism 47. Suspended.

  That is, the front end of the cushion unit 48 is swingably connected to the mounting bridge 49 that spans the pair of left and right lower tubes 29 of the vehicle body frame 15. The link mechanism 47 includes a cushion lever 50 and a cushion lever rod 51. The cushion lever 50 is pivotally supported by a reinforcement 52 spanned on the lower tube 29 of the vehicle body frame 15 by using a pivot shaft 56 as a pivot point, and one end of the cushion lever 50 is operated in the cushion unit 48. The tip of the rod 53 is rotatably connected. One end of the cushion lever rod 51 is rotatably connected to a connection boss portion 54 formed at the front lower portion of the crankcase 33 in the engine 35 of the engine unit 25 using a rod shaft 68 as a connection point. Further, the other end of the cushion lever rod 51 is rotatably connected to the other end of the cushion lever 50 by using a link shaft 55 as a connection point.

Accordingly, when the engine unit 25 and the rear wheel 24 swing in the vertical direction around the pivot shaft 46, the cushion lever 50 of the link mechanism 47 is centered on the pivot shaft 56 via the cushion lever rod 51 of the link mechanism 47. The rotation of the cushion lever 50 is absorbed by the expansion and contraction of the cushion unit 48, and the swinging of the engine unit 25 and the rear wheel 24 is buffered.

  As shown in FIGS. 2 and 3, a storage box 57 capable of storing articles such as a helmet is attached to the main tube 28 of the vehicle body frame 15. Then, the double sheet 20 shown in FIG. 1 is disposed above the storage box 57. The double seat 20 is supported by a seat rail 30 and supported at its tip by an unillustrated hinge installed on a support bracket 31 (FIG. 2) so as to be opened and closed. Therefore, when the double sheet 20 is closed, the bottom plate of the double sheet 20 closes the upper opening of the storage box 57.

  The aforementioned engine unit 25 is disposed below the storage box 57. The fuel tank 58 stores fuel in front of the engine unit 25 and between the main tube 28 and the lower tube 29 of the vehicle body frame 15. Is placed. The fuel tank 58 is accommodated in the center tunnel 22 shown in FIG.

  As shown in FIGS. 3 to 5, an engine intake system 63 having an air cleaner 59, an intake duct 60, an air-fuel mixture supply device 61 and an intake pipe 62 is disposed above the engine unit 25 and in front of the storage box 57. The Of these, the air cleaner 59 is attached to the engine unit 25, introduces outside air, removes dust and the like in the outside air, and produces clean air.

  The air-fuel mixture supply device 61 is connected to an air cleaner 59 using an intake duct 60 and connected to an intake port of the cylinder head 41 of the cylinder assembly 34 via an intake pipe 62. The air-fuel mixture supply device 61 is, for example, a throttle body and includes a fuel injector 64. The fuel injector 64 is connected to the fuel tank 58 using a fuel hose 65. The air-fuel mixture supply device 61 sprays fuel from the fuel injector 64 into clean air introduced from the air cleaner 46 to form an air-fuel mixture, and supplies this air-fuel mixture to the intake port of the cylinder head 41 via the intake pipe 62.

  As shown in FIGS. 4 and 5, an exhaust pipe 66 is connected to the exhaust port of the cylinder head 41 of the cylinder assembly 34 below the cylinder assembly 34 in the engine unit 25. The exhaust pipe 66 extends rearward and is connected to a muffler (not shown). An engine exhaust system 67 is configured using the exhaust pipe 66 and the muffler. The engine exhaust system 67 and the engine intake system 63 are provided together with the engine unit 25 so as to be swingable in the vertical direction about the pivot shaft 46.

  As shown in FIGS. 6 and 7, in the power transmission device 36 in the engine unit 25, a belt case 70 integrally provided on the left side surface of the crankcase 33 of the engine 35 extends rearward. The case cover 71 closes the opening formed on the left side in the vehicle width direction, and the belt-type continuously variable transmission 37 is built in the belt case 70 and the case cover 71. In this embodiment, the belt-type continuously variable transmission 37 changes the belt winding effective diameter of the drive pulley 73 by the power of the speed change electric motor 72 as a speed change actuator, and thereby the driven pulley with respect to the drive pulley 73. The rotational speed of 74 is changed steplessly, that is, the gear ratio is changed steplessly.

  That is, the crankshaft 75 of the engine 35 extends in the vehicle width direction and is pivotally supported by the crankcase 33, and the left end thereof enters the front portion of the belt case 70 to drive the drive shaft of the belt-type continuously variable transmission 37. It becomes. A drive pulley 73 is mounted on the free end of the crankshaft 75, and the drive pulley 73 is driven by the engine 35.

  On the other hand, a driven shaft 76 is supported at the rear portion of the belt case 70, and a driven pulley 74 and a centrifugal clutch 77 are mounted on the driven shaft 76. A V belt 78 is wound between the driving pulley 73 and the driven pulley 74, and the driven pulley 74 is rotated by the driving pulley 73 via the V belt 78.

  As shown in an enlarged view in FIG. 7, the drive pulley 73 is a fixed half 79 provided integrally with the crankshaft 75 so as to rotate integrally therewith, and is positioned so as to face the fixed half 79, and is integrally rotated with the crankshaft 75. And a movable half 80 that is movable in the axial direction. Between the inner side surfaces of the fixed half body 79 and the movable half body 80, both side surfaces of the V-belt 78 are sandwiched and frictionally engaged.

  A slider gear 82 is provided relative to the movable half body 80 via a slider gear bearing 81 so as to be relatively rotatable and integrally movable in the axial direction. A female screw 83 is formed on the inner peripheral surface of the sleeve portion 82 </ b> B of the slider gear 82.

  Further, a screw shaft 84 is fixed to the crankcase 33 using a fixing bracket 85. A male screw 86 formed on the outer peripheral surface of the screw shaft 84 is screwed into a female screw 83 of the slider gear 82 to constitute a trapezoidal three-thread screw mechanism as the thrust generating mechanism 87.

  On the other hand, the crankcase 33 is provided with a speed changing electric motor 72 that rotationally drives the slider gear 82. Two reduction intermediate gears (actuator counter gear 89 and actuator idler gear 90) are pivotally supported between the pinion gear 88 of the motor shaft of the speed change electric motor 72 and the gear portion 82A of the slider gear 82, and all the gears are supported. Are engaged.

  The rotational force of the speed changing electric motor 72 is decelerated by the actuator counter gear 89 and the actuator idler gear 90 and transmitted to the slider gear 82, which rotates the slider gear 82 by a predetermined angle. As a result, in the thrust generating mechanism 87, a thrust along the axial direction is generated between the male screw 86 of the screw shaft 84 and the female screw 83 of the slider gear 82, and the slider gear 82 together with the movable half 80 of the drive pulley 73 is 7 moves in the axial direction between a low-side restriction position L0 and a high-side restriction position H0. At the low-side restriction position L0, the effective V-belt winding diameter of the drive pulley 73 is the minimum diameter D1, and at the high-side restriction position H0, the V-belt winding effective diameter is the maximum diameter D2.

  The slider gear 82 rotates about 3/4, for example, before moving from the low-side restriction position L0 to the high-side restriction position H0. When the slider gear 82 and the movable half 80 move to the low-side regulating position L0, the low-side stopper abutment protrusion 91 protruding from the slider gear 82 contacts the low-side stopper 92 formed on the fixed bracket 85. The rotation stops upon contact. Further, when the slider gear 82 and the movable half body 80 are moved to the high-side restriction position H0, a high-side stopper abutting pin 93 protruding from the outer portion of the slider gear 82 is formed on the belt case 70. The rotation stops upon contact with the side stopper 94.

  In the driven pulley 74 shown in FIG. 6, when the effective V-belt winding diameter of the driving pulley 73 is the minimum diameter D1, the effective V-belt winding diameter is the maximum diameter d1, and the effective V-belt winding diameter of the driving pulley 73 is When the maximum diameter is D2, the V belt winding effective diameter is the minimum diameter d2. The rotation of the driving pulley 73 is transmitted to the driven pulley 74 by the V belt 78.

  At the start of the scooter type motorcycle 10, the speed change electric motor 72 moves the slider gear 82 and the movable half 80 to the vicinity of the low-side restriction position L0, and the effective V-belt winding diameter of the drive pulley 73 is near the minimum diameter D1. As the vehicle accelerates, the speed change electric motor 72 moves the slider gear 82 and the movable half 80 toward the high-side restriction position H0 so that the effective V-belt winding diameter of the drive pulley 73 approaches the maximum diameter D2. . Thereby, the vehicle speed of the scooter type motorcycle 10 is changed steplessly.

  By the way, in the belt type continuously variable transmission 37 as described above, as shown in FIGS. 4 and 5, the transmission electric motor 72 is disposed below the cylinder 40 of the cylinder assembly 34 and in front of the crankcase 33. Further, it is disposed above the cushion lever rod 51 in the link mechanism 47. The transmission electric motor 72 is disposed in the vicinity of the pivot shaft 56 in which the cushion lever 50 of the link mechanism 47 is pivotally supported by the lean force 52 of the vehicle body frame 15.

  Further, the transmission electric motor 72 is disposed in the vicinity of the link shaft 55, which is a connection point between the cushion lever 50 and the cushion lever rod 51, and the connection boss portion 54 of the crankcase 33 and the cushion lever rod 51. It is arrange | positioned in the rod shaft 68 vicinity which is a connection point. Further, as shown in FIG. 6, the transmission electric motor 72 is disposed at a position passing through the vehicle width direction center line O of the body frame 15 that substantially coincides with the cylinder axis of the engine 35.

Therefore, according to the present embodiment, the following effects (1) to (5) are obtained.
(1) The speed change electric motor 72 of the belt type continuously variable transmission 37 is disposed below the cylinder 40 of the cylinder assembly 34 in the engine 35 of the engine unit 25 and in front of the crankcase 33 of the engine 35. For this reason, compared with the case where the transmission electric motor 72 is disposed above the crankcase 33, the transmission electric motor 72 is disposed below the crankshaft 75, so that the center of gravity of the engine unit 25 can be set low. As a result, the steering stability of the scooter type motorcycle 10 can be improved.

  (2) The transmission electric motor 72 is disposed below the cylinder 40 of the cylinder assembly 34 in the engine 35 of the engine unit 25 and in front of the crankcase 33 of the engine 35. For this reason, the shifting electric motor 35 is not disposed above the engine unit 25, and as a result, the space above the engine unit 25 can be effectively used for expanding the capacity of the storage box 57 and the like.

  (3) The transmission electric motor 72 is disposed below the cylinder 40 of the cylinder assembly 34 and in front of the crankcase 33 and further above the cushion lever rod 51 of the link mechanism 47. The space surrounded by the cylinder 40, the crankcase 33, and the cushion lever rod 51 is narrow for placing the starter motor 95. However, since the speed change electric motor 72 can be placed, this space is limited. It can be used effectively.

  (4) When the engine unit 25 swings, the cushion lever rod 51 rotates around the link shaft 55 that is a connection point with the cushion lever 50 and is a connection point with the connection boss portion 54 of the crankcase 33. It rotates around the rod shaft 68. For this reason, the transmission electric motor 72 and the cushion shaft 51 are arranged in the vicinity of the link shaft 55 and the rod shaft 68, which are the connection points of the cushion lever rod 51. The relative displacement with the lever rod 51 can be minimized.

  (5) Since the shifting electric motor 72 is disposed at a position passing through the vehicle width direction center line O of the body frame 15, the weight balance in the vehicle width direction of the engine unit 25 is improved, and the scooter type motorcycle 10 The steering stability can be improved.

  As mentioned above, although this invention was demonstrated based on the said embodiment, this invention is not limited to this, In the implementation stage, you may change a component in the range which does not deviate from the summary. Moreover, you may combine suitably the some component currently disclosed by the above-mentioned embodiment, and may delete some components from all these components.

15 Body frame 25 Engine unit 33 Crankcase 34 Cylinder assembly 35 Engine 37 Belt type continuously variable transmission 40 Cylinder 46 Pivot shaft 47 Link mechanism 48 Cushion unit 50 Cushion lever 51 Cushion lever rod 56 Pivot shaft (Pivot point)
72 Electric motor for speed change (actuator for speed change)
73 Driving pulley 74 Driven pulley 78 V-belt O Vehicle width direction center line

Claims (6)

The cylinder assembly includes an engine tilted forward with respect to the crankcase and is built in a unit swing type engine unit that is swingably supported by the vehicle body frame.
By having a drive pulley driven by the engine and a driven pulley that is rotated by the drive pulley via a belt, by changing the belt winding effective diameter of the drive pulley by the power of the shift actuator, In a belt type continuously variable transmission for a motorcycle that changes the rotational speed of the driven pulley relative to the drive pulley,
A motorcycle belt, wherein the speed change actuator is disposed below a cylinder of the cylinder assembly and in front of the crankcase , which is positioned below the crankshaft of the engine in a side view. Type continuously variable transmission. In the unit swing type engine unit, the upper part of the crankcase in the engine is pivotally supported by the vehicle body frame, and the lower front part of the crankcase is buffered and suspended on the vehicle body frame by a cushion unit via a link mechanism. ,
The link mechanism includes a cushion lever pivotally supported by the vehicle body frame and having one end connected to the cushion unit, one end connected to the front lower part of the crankcase, and the other end to the other end of the cushion lever. A cushion lever rod to be connected,
The belt-type continuously variable transmission for a motorcycle according to claim 1, wherein the speed-changing actuator is disposed above the cushion lever rod. The belt-type continuously variable transmission for a motorcycle according to claim 2, wherein the shifting actuator is disposed in the vicinity of a connection point between the cushion lever and the cushion lever rod in a side view. The belt-type continuously variable transmission for a motorcycle according to claim 2, wherein the shifting actuator is disposed in the vicinity of a connection point between the crankcase and the cushion lever rod in a side view. 2. The belt type continuously variable transmission for a motorcycle according to claim 1, wherein the speed change actuator is disposed at a position passing a center line in a width direction of the body frame. The belt-type continuously variable transmission for a motorcycle according to claim 1, wherein the transmission actuator is a transmission electric motor.

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