JP4014555B2 - V belt type continuously variable transmission - Google Patents

Description

  The present invention relates to a belt-type continuously variable transmission, and more particularly to a belt-type continuously variable transmission that can control a gear ratio with an electric actuator.

  A V-belt is stretched between a drive pulley connected to a prime mover such as an engine and a driven pulley connected to a load, and the winding ratio of the V-belt around the drive pulley and the driven pulley is continuously changed to change the gear ratio. A V-belt type continuously variable transmission to be controlled is known. In order to change the winding diameter of the V-belt, the movable pulley portion is displaced in the direction of the support shaft among the fixed pulley portion and the movable pulley portion constituting the driving pulley and the driven pulley, respectively, and the distance between both pulley portions is changed. The winding diameter is changed.

  For example, JP-A-5-44827 discloses a continuously variable transmission in which a movable pulley portion is driven by a motor. In this continuously variable transmission, a movable pulley portion of a drive pulley is coupled to a slider via a bearing, and this slider is coupled to a motor via a gear.

The gear ratio is controlled by detecting the operating state of the engine from the engine speed, throttle opening, and the like. Whether the gear ratio is an appropriate value is detected as the position of the movable pulley portion, and the motor is feedback controlled based on the detected position of the movable pulley portion.
Japanese Patent Laid-Open No. 5-44827

  The continuously variable transmission is formed integrally with a crankcase of an engine, and includes a transmission case that forms a partition wall with the crank chamber, a transmission case cover that covers the transmission case, and an outer cover that further covers the transmission case cover. . The outer cover closes the cooling air circulation hole and the like, and is configured with emphasis on the appearance design, so that the transmission is substantially protected by the transmission case and the transmission case cover. Therefore, as described above, in the transmission in which the slider is connected to the motor via the gear device and the slider is moved by this motor to control the transmission ratio, these are covered with the transmission case cover.

  However, in order to configure the transmission case cover so as to cover the gear device and the motor, a complicated shape must be formed integrally. Therefore, the mold for manufacturing must be complicated, and the assembly with the transmission case is not easy.

  In view of the above-described problems of the prior art, the present invention simplifies the shape of the transmission case and simplifies the cover of the motor and gear device when providing a motor and gear device for adjusting the gear ratio. An object is to provide a V-belt type continuously variable transmission.

  The present invention has a drive pulley driven by an engine and a driven pulley driven by the drive pulley via a V-belt, and each of the pulleys is fixed to a respective support shaft and the support. A movable part provided slidably in the axial direction with respect to the shaft, and the movable part of the drive pulley is displaced in the axial direction by a motor to change the interval between the fixed part and the movable part, In a belt-type continuously variable transmission that changes the number of rotations of the driven pulley relative to the drive pulley by sliding the movable part of the driven pulley according to the change, the gear device that transmits the power of the motor to the movable part of the drive pulley A transmission case that houses the drive pulley, the driven pulley, and the gear device, and is coupled to the transmission case to cover the drive pulley and the driven pulley. And the dynamic case cover is coupled to the transmission case and an actuator cover for covering the gear unit, the motor to the actuator cover has a first feature in that it is supported.

  Further, the present invention has a second feature in that the actuator cover and the transmission case constitute a wall surface of a water pump that circulates water to the engine.

  Furthermore, the present invention is a V-belt continuously variable transmission used in an engine having a cylinder protruding toward the front of a vehicle, wherein the gear device and the motor are connected to the drive pulley. A third feature is that it is provided on the protruding direction side.

  According to the present invention having the above characteristics, the actuator cover that covers the gear device and the motor that drives the drive portion of the drive pulley of the transmission is formed separately from the transmission case cover that covers the belt device that is the transmission body. ing. Therefore, it is easy to manufacture molds when manufacturing these covers, and workability when assembling or disassembling these covers in the transmission case is also good.

  According to the 2nd characteristic, since a water pump can also be covered simultaneously, a maintenance is easy.

  According to the third feature, in the engine in which the cylinder protrudes, the motor and the gear device can be laid out so as to be adjacent to the protruding portion. That is, the actuator means of the transmission can be laid out without generating an extra protruding portion.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 3 is an external side view of a scooter type motorcycle including a continuously variable transmission according to an embodiment of the present invention. In the figure, a vehicle body front portion 2 and a vehicle body rear portion 3 of a scooter type motorcycle 1 are connected via a lower floor portion 4, and the skeleton of the vehicle body extends from the down tube 6 and the down tube 6 to the rear upper side. A tube 7 is used. A seat 8 is disposed above the main tube 7. A storage box such as a helmet and a fuel tank are provided between the seat 8 and the main tube 7 (both not shown). The sheet 8 also serves as a lid for the storage box.

  The front end of the down tube 6 is joined to a head pipe 5 provided in the vehicle body front portion 2. A front fork 12 is pivotally supported on the head pipe 5. A handle 11 is attached to an upper extension portion of the front fork 12, and a front wheel 13 is pivotally supported at the lower end of the front fork 12. The upper portion of the handle 11 is covered with a handle cover 33 that also serves as an instrument panel.

  A bracket 15 is provided at the lower end of the rising portion of the main tube 7. A hanger bracket 18 is connected to the bracket 15 via a link member 16, and a swing unit 17 is swingably supported. The rear part of the swing unit 17 and the rear part of the main tube 7 are connected by a rear suspension 22 having a buffer member. A single-cylinder four-cycle engine 200 is mounted on the front portion of the swing unit 17. A V-belt continuously variable transmission 35 and a speed reducer 38 are provided behind the engine 200. The rear wheel 21 is coupled to an output shaft (described later) of the speed reducer 38. That is, the output of the engine 200 is transmitted to the rear wheel 21 via the continuously variable transmission 35 and the speed reducer 38.

  An intake pipe 23 extending from the cylinder head 32 of the engine 200 is connected to the front portion of the swing unit 17. The intake pipe 23 is provided with a carburetor 24 and an air cleaner 25 connected to the carburetor 24. A parking main stand 26 is supported on the hanger bracket 18 provided on the crankcase 31 of the swing unit 17. A kick arm 28 is fixed to the kick shaft 27 protruding from the external cover 36 of the transmission 35, and a kick pedal 29 is provided at the tip of the kick arm 28.

  FIG. 1 is a front sectional view of a continuously variable transmission, and FIG. 2 is a rear sectional view thereof. 1 and 2, the continuously variable transmission includes a transmission case 40 that is a part of the crankcase 31 of the engine 200, a transmission case cover 401 that covers the transmission case 40 from the left side of the vehicle, and a transmission case cover 401. Further, the outer cover 36 and the actuator cover 58 that are assembled to the front part of the transmission case cover 401 (front part in the traveling direction of the vehicle) and cover the motor 57 and the gear device 60 as the actuator for driving the transmission are used. Form.

  In FIG. 1, the crankshaft 41 of the engine 200 is supported by a bearing 42 provided in the transmission case 40 and another bearing (not shown). A portion 43 of the crankshaft 41 protruding outward from the transmission case 40 is a support shaft for the drive pulley 45 and a drive shaft for the continuously variable transmission.

  A guide pipe 44 is attached to the outer periphery of the drive shaft 43. The drive pulley 45 includes a fixed pulley portion 451 provided at the shaft end of the drive shaft 43 and a movable pulley portion 452 that is movable in the axial direction of the drive shaft 43. On the driving pulley 45, a V-belt 100 is hung on a driven pulley described later. The fixed pulley portion 451 is fixed to the drive shaft 43 by a nut 46 screwed to a screw portion provided at the shaft end of the drive shaft 43. The hub 453 of the movable pulley portion 452 is slidably fitted to the outer periphery of the guide pipe 44 so that the movable pulley portion 452 can move in the drive shaft direction.

  A long hole in the axial direction of the drive shaft 43, that is, a guide hole 47 is formed in the hub 453 of the movable pulley portion 452. A guide pin 48 is erected on the outer periphery of the guide pipe 44, and a head 481 of the guide pin 47 projects into the guide hole 47. A collar 49 such as a fluororesin having a small surface friction coefficient is provided on the head of the guide pin 48 so as to cover at least a portion facing the inner surface of the guide hole 47. Preferably, a portion facing the outer periphery of the guide pipe 44 is also covered as shown. Thus, the movable pulley portion 452 to which the hub 453 is fixed is restricted in displacement in the rotational direction with respect to the guide pipe 44, that is, the drive shaft 43 by the guide pin 48, and can move only in the axial direction with respect to the drive shaft 43. Since the guide pin 48 slides with the guide hole 47 of the hub 453 via the collar 49, the movement of the movable pulley portion 452 is smooth and the generation of sliding noise is also suppressed.

  A bearing holding ring 50 is fitted to the outer periphery of the hub 453 of the movable pulley portion 452, and an inner ring of the bearing 51 is fitted to the outer circumference of the holding ring 50. A slider holding ring 52 is fitted to the outer ring of the bearing 51, and a slider 53 is fitted to the holding ring 52. The slider 53 has a cylindrical shape, and a gear 531 is formed on the outer side, and a feed ring 54 having a female screw (screw screw) formed on the inner periphery is fitted on the inner side. The female screw of the feed ring 54 is screwed with a male screw (screw screw) formed on the outer periphery of the cylindrical body 55. The cylindrical body 55 is fixed to the transmission case 40 with a bolt 56 via a flange portion welded to the outer periphery thereof.

  Next, a drive unit that transmits power to the gear 531 of the slider 53 will be described. The drive unit that drives the gear 531 of the slider 53 includes a gear device 60 and a motor 57. The motor 57 includes a base plate 571 and a housing 572, and the base plate 571 is fitted and fixed to the actuator cover 58 of the transmission case 40. An output gear 591 is formed at the tip of the motor shaft 59.

  The gear device 60 includes first-stage gears 62 and 63 fixed to a common shaft 61 and second-stage gears 65 and 66 fixed to another common shaft 64. Each gear of the gear device 60 is preferably made of resin in order to reduce operation noise. The shaft 61 of the first gear is supported by a bearing 67 provided on the transmission case 40 and a bearing 68 provided on the actuator cover 58. On the other hand, the shaft 64 of the second gear is supported by a bearing 69 provided in the transmission case 40 and a bearing 70 provided in the actuator cover 58. Of the first gear, the large gear 62 meshes with the output gear 591 and the small gear 63 meshes with the large gear 65 of the second gear. The small gear 66 of the second gear meshes with the gear 531 of the slider 53.

  A gear 641 is formed on an extension of the shaft 64 of the second gear that penetrates the bearing 70. The gear 641 is a worm gear, and the worm gear 641 meshes with a rotary variable resistor or a rotary potentiometer as a rotation sensor (rotation sensor and worm wheel will be described later). Thus, the shaft 64 has a function as a sensor output shaft that transmits the rotation amount of the gear device 60 to the rotation sensor.

  Ribs 402 are formed on the transmission case 40 so as to surround the outer periphery of the gear 531 formed on the slider 53. A restriction plate 72 is attached to the end of the rib 402 by a bolt 71. A limit of movement of the slider 53 toward the drive pulley 45 is defined by the restriction plate 72. Normally, the gear 531 of the slider 53 moves within a range where it does not contact the restriction plate 72.

  With the above configuration, the rotation of the motor 57 is sequentially transmitted to the gear 531 of the slider 53 through the output gear 591, the first stage gears 62 and 63, and the second stage gears 65 and 66, thereby rotating the slider 53. When the slider 53 is rotated, the feed ring 54 rotates around the cylindrical body 55, and as a result, the slider 53 is relatively screw-fed in the axial direction of the crankshaft 41. The displacement direction of the slider 53 due to the action of the screw depends on the direction of the female screw and the male screw of the feed ring 54 and the cylindrical body 55.

  When the slider 53 is displaced along the drive shaft 43, the movement is transmitted to the movable pulley portion 452 via the bearing 51, and the distance between the movable pulley portion 452 and the fixed pulley portion 451 changes. When the distance between the fixed pulley portion 451 and the movable pulley portion 452 is increased, the V-belt 100 operates so that the winding diameter of the drive pulley 45 is reduced in combination with the movement of the driven pulley described later. On the other hand, the force in the direction in which the distance between the fixed pulley portion 451 and the movable pulley portion 452 is narrowed causes a component force to push the V belt 100 in the outer peripheral direction of the drive pulley 45, and coupled with the movement of the driven pulley described later. Increase the winding diameter of 100.

  The position of the slider 53 represents the transmission ratio of this transmission. Therefore, the position of the slider 53 can be detected by the rotation sensor that detects the rotation position of the worm gear 641, and the detection result can be fed back to the control of the gear ratio.

  Next, the rear configuration of the continuously variable transmission will be described. In FIG. 2, the driven pulley 73 includes a fixed pulley portion 731 and a movable pulley portion 732. A driven shaft (support shaft of the driven pulley) 74 that supports the driven pulley 73 is supported by bearings 75 and 76. A bearing 77 is fitted into one side of the driven shaft 74, that is, an end portion on the left side of the bearing 75 in FIG. 2, and a collar 78 is put on the tip side of the bearing 77. A collar-like clutch plate 79 is welded to the collar 78. A screw is formed at this end of the driven shaft 74, and a nut 80 is screwed onto the screw, and the collar 78 and the clutch plate 79 are fixed to the driven shaft 74 via the inner ring of the bearing 77. A bearing 81 is provided on the outer periphery of the intermediate portion of the driven shaft 74, and the hub 82 of the fixed pulley portion 731 is mounted on the outer periphery of the driven shaft 74 by the bearing 81 and the bearing 77.

  Further, the hub 83 of the movable pulley portion 732 is provided on the outer periphery of the hub 82 of the fixed pulley portion 731. The movable pulley portion 732 is slidable in the longitudinal direction of the driven shaft 74 with respect to the fixed pulley portion 731. A guide pin 84 is erected on the hub 82. The guide hole 831 provided in the hub 83 engages with the head of the guide pin 84, thereby restricting the rotation of the movable pulley portion 732 with respect to the hub 83.

  A clutch shoe support plate 85 is fixed to the end of the hub 82 of the fixed pulley portion 731 by a nut 86. A clutch shoe 87 is provided on the support plate 85. The clutch shoe 87 is fixed to an arm 90 having a boss 89 pivotally supported by a pivot 88 erected on the support plate 85. The arm 90 is biased by a spring 91 in a direction in which the crush 87 is separated from the inner surface of the clutch plate 79. Further, a coil spring 92 that urges the movable pulley portion 732 toward the fixed pulley portion 731 is interposed between the movable pulley portion 732 and the support plate 85.

  A reduction gear 38 is provided at the rear of the continuously variable transmission. The speed reducer 38 has an input gear 94, intermediate gears 95 and 96, and a final gear 97 provided between the other end of the driven shaft 74, that is, the bearings 75 and 76 in FIG. The input gear 94 meshes with the intermediate gear large gear 95, and the intermediate gear small gear 96 meshes with the final gear 97. The shafts of the intermediate gears 95 and 96 are supported by bearings 98 and 99, and the shaft of the final gear 97, that is, the output shaft 101 is supported by bearings 102 and 103. The bearings 76, 98, and 103 are fitted into the rear casing 403 following the rib 402, and the bearings 75, 99, and 102 are fitted into the reduction gear cover 104 fixed to the casing 403.

  A sensor plate 105 is provided on a side surface of the hub 82 of the fixed pulley portion 731, and a magnetic sensor 106 is provided to face the outer periphery of the sensor plate 105. The sensor plate 105 is made of iron, and the sensor plate 105 made of iron has one or a plurality of protruding or recessed portions on the outer periphery. Therefore, the output of the magnetic sensor 106 changes at this shape change portion, and the number of rotations of the driven pulley 73 can be detected based on the state of this change, for example, the output change interval. The magnetic sensor 106 is fixed to the speed reducer cover 104.

  In the above configuration, when the winding diameter of the V-belt is expanded on the drive pulley 45 side, the tension of the V-belt 100 increases, and the tension increases so that the gap between the movable pulley portion 732 and the fixed pulley portion 731 of the driven pulley 73 is increased. The force that pushes out acts. As a result, the winding diameter of the V-belt 100 is reduced on the driven side. That is, the reduction ratio is reduced. On the other hand, when the winding diameter of the V-belt is reduced on the drive pulley 45 side, the tension of the V-belt 100 is reduced, and the urging force of the coil spring 92 reduces the tension component applied to the V-belt 100 by reducing the tension. If it exceeds, the force which reduces between the movable pulley part 732 and the fixed pulley part 731 of the driven pulley 73 will arise. As a result, the winding diameter of the V belt 100 is increased on the driven side. That is, the reduction ratio is increased.

  When the rotation of the driven pulley 73 reaches a predetermined value, the clutch shoe 87 contacts the clutch plate 79 due to an increase in centrifugal force. Then, the driven shaft 74 to which the clutch plate 79 is coupled rotates, and the output shaft 101 rotates through the input gear 94, the intermediate gears 95 and 96, and the final stage gear 97. The rotation of the output shaft 101 is transmitted to the rear wheel 21 so that the motorcycle can travel.

  FIG. 4 is a view of the transmission case 40 and the actuator cover 58 as viewed from the left side of the vehicle body. In the figure, the transmission case 40 and the actuator cover 58 meet at the meeting portion IF. The meeting part IF is provided with a seal (described later) that makes the meeting part IF liquid-tight. As will be described in detail later, the meeting part IF is formed by a plane perpendicular to the plane parallel to the paper surface of this figure. The portions F and F1 of the transmission case 40 and the actuator cover 58 are formed on the same plane, and the transmission case cover 401 is attached to this portion, that is, the common plane.

  5 is a front view of the actuator cover 58, and FIG. 6 is a cross-sectional view taken along line AA of FIG. The actuator cover 58 covers the components of the deceleration system from the motor 57 to the shaft 64 as described above, and also serves as a water pump cover for circulating engine cooling water. In FIG. 5, a worm wheel 110 meshing with a worm gear 641 supported by a bearing 70 fitted in the actuator cover 58 and a shaft 111 thereof are accommodated, and a cylindrical protrusion 581 for supporting the shaft 111 is formed. . A rotation sensor 112 that detects the rotational position of the worm wheel 110 is coupled to the shaft 111. The detection output of the rotation sensor 112 is supplied to a control device (not shown), and based on this detection output, the position of the movable pulley portion 452 is detected via the gears 641, 65, 66, 531 linked to the worm wheel 110. .

  The actuator cover 58 includes bosses 582 and 583 for holding the base plate 571 of the motor 57, and seats 585 and 586 provided adjacent to a boss hole 584 for receiving the hub of the base plate 571 of the motor 571. Have.

  Furthermore, the actuator cover 58 forms the outer wall of the water pump 113 in combination with a part of the transmission case 40, as can be well understood from FIG. The impeller 114 and the shaft 115 are accommodated in the space surrounded by the outer wall. The shaft 115 is connected to the engine by a transmission device (not shown) and is driven to rotate by the rotation of the engine. The base 116 is an inlet for cooling water circulated from the radiator via the thermostat, and the base 117 is an inlet for cooling water circulated without going through the radiator. When the engine is started or when the cooling water temperature is low, water is introduced from the base 117, and when the cooling water temperature is equal to or higher than a predetermined value, water whose temperature has been lowered is introduced from the base 116 via the radiator.

  7 is a plan view of the seal disposed between the transmission case 40 and the actuator cover 58, FIG. 8 is a side view of the main part of the seal, and FIG. 9 is an enlarged view of the end of the seal. The seal 120 includes an annular part 121 for sealing the water pump 113 in a liquid-tight manner, a long part 122 extending from the annular part 121 to one side, and a long part 123 extending to the other side. The seal 120 is formed so that it can be bent in a direction substantially perpendicular to the paper surface of the drawing in order to maintain a liquid-tight two-dimensional surface where the transmission case 40 and the actuator cover 58 meet. That is, the shapes of the portions 127 and 128 extending from the locking projections 124 and 125 to the end side and the portion 122 between the projections 124 and 125 are different. In other words, the portion 122 has a circular cross-sectional shape so as to be fitted in a groove described later, whereas the portions 127 and 128 on the end side from the locking projections 124 and 125 are the end surfaces of the actuator cover 58. (See FIGS. 8 and 9).

  That is, the end portion of the seal 120 includes a box-shaped portion 128 whose one surface is opened so as to cover the end portion of the actuator cover 58, and a portion 129 that couples the box upper portion 128 and the protrusion 124. At the tip of the box-shaped portion 128, a hook portion 128 a that is wound around the end surface of the actuator cover 58 is provided.

  10 is a rear view of the actuator cover, that is, a view seen from the transmission case 40 side, and FIG. 11 is a cross-sectional view taken along the line BB of FIG. In FIG. 10, a seal groove 130 for fitting the seal 120 along the substantially outer contour of the actuator cover 58 is formed. The seal groove 130 has an annular groove 131 into which the annular portion 121 of the seal 120 is fitted and a long groove 132 extending from the annular groove 131. A lead-out part 133 for extending the seal 120 outward from a part of the annular groove 131 and a lead-out part 134 for extending the seal 120 outward from the long groove 132 are formed. Circular recesses 135 and 136 for fixing the seals are provided adjacent to the drawer portions 133 and 134, respectively.

  10 and 11, the meeting portion between the transmission case 40 and the actuator cover 58 is an inclined portion, that is, a plane parallel to the longitudinal direction of the vehicle body (a plane parallel to the planes F and F1) F3 and the plane F3. It consists of the inclined surfaces F4 and F5 that stand up. The seal 120 indicated by the phantom line in FIG. 11 is disposed along the surface F3 and the surfaces F4 and F5, and the projections 124 and 125 at the intermediate portion are locked to the recesses 135 and 136, respectively, and the hooks at the end portions are hooked. The portion 128a is hooked in the end surface groove 58a of the actuator cover 58. The hook portion 128a is pressed and fixed by the transmission case cover 401.

  As described above, in the transmission of the present embodiment, the transmission case 40 and the transmission case cover 401 are sealed with a higher sealing function so that the liquid tightness can be maintained separately from the sealing means that is airtight particularly for the purpose of dust prevention. 120 was provided. Therefore, the space between the actuator cover 58 which is also a member constituting the wall surface of the water pump and the transmission case 40 can be in a sealed state suitable for the water pump.

1 is a front sectional view of a belt-type continuously variable transmission according to an embodiment of the present invention. 1 is a rear sectional view of a belt type continuously variable transmission according to an embodiment of the present invention. 1 is a side view of a motorcycle according to an embodiment of the present invention. It is a front view of a transmission case and an actuator cover. It is a front view of the gear unit cover provided in the front part of a continuously variable transmission. It is sectional drawing which shows the wall part of the water pump formed with an actuator cover and a transmission case. It is a top view of a seal. It is a principal part side view of a seal | sticker. It is an edge part enlarged view of a seal | sticker. It is a rear view of an actuator cover. It is BB sectional drawing of FIG.

Explanation of symbols

40 ... Transmission case, 41 ... Crankshaft, 45 ... Drive pulley, 53 ... Slider, 57 ... Motor, 58 ... Actuator cover, 60 ... Gear device, 73 ... Drive pulley, 100 ... V belt, 112 ... Rotation sensor, 113 ... Water pump, 451 ... Drive pulley part, 452 ... Movable pulley part

Claims (4)

A drive pulley driven by the engine and a driven pulley driven by the drive pulley via a V-belt;
Each pulley is composed of a fixed part fixed to the respective support shaft and a movable part provided slidably in the axial direction with respect to the support shaft,
The movable part of the drive pulley is displaced in the axial direction by a motor to change the distance between the fixed part and the movable part, and the driven pulley rotates relative to the drive pulley by sliding the movable part of the driven pulley according to the change. In the belt type continuously variable transmission that changes the number,
A gear device for transmitting the power of the motor to the movable part of the drive pulley;
A transmission case that houses the drive pulley, the driven pulley, and the gear device;
An actuator cover coupled to the transmission case and covering only the drive gear device;
The motor is supported by the actuator cover ,
The movable part of the drive pulley is arranged on the engine side, the fixed part is arranged on the outer cover side far from the engine, and the gear device is arranged close to one side of the engine with respect to the drive pulley. V-belt continuously variable transmission characterized by this. The V-belt type continuously variable transmission according to claim 1, further comprising a transmission case cover mounted on a coplanar surface of the actuator cover and the transmission case.   The V-belt type continuously variable transmission according to claim 1, wherein the actuator cover and the transmission case constitute a wall surface of a water pump for circulating water to the engine. A V-belt type continuously variable transmission used for an engine having a cylinder protruding toward the front of a vehicle,
The V-belt type continuously variable transmission according to any one of claims 1 to 3, wherein the gear device and the motor are provided on the drive pulley side in a protruding direction of the cylinder.

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