Title of Invention

"A V-BELT TYPE CONTINUOUSLY VARIABLE TRANSMISSION"

Abstract

A V-belt type continuously variable transmission, having: a drive pulley comprising a fixed section fixed on a support shaft, and a movable section, the moveable section of the drive pulley being displaced in the axial direction by a motor to vary a distance between the fixed section and the movable section, and the rotational speed of the driven pulley being varied in accordance with the drive pulley as a result of the movable section of the driven pulley sliding according to a variation in the distance, wherein a gear unit is provided for transmitting power of the motor to the movable section of the drive pulley, an actuator cover is provided for covering the gear unit, a shaft is provided arranged in parallel to the support shaft of the drive pulley, the movable section of the drive pulley is arranged near to the inner side of the motorcycle with respect of the fixed section, a rotation sensor is further provided which is connected to a shaft orthogonal to a sensor output shaft as a shaft nearest to the support shaft of the drive pulley, of the shafts of a plurality of gears composing the gear unit and which is arranged in front fo the sensor output shaft in a side view of the motorcycle, and the shaft orthogonal to the sensor output shaft is stored in a cylindrical projecting portion formed on the actuator cover, and also arranged between the sensor output shaft and the motor in the side view of the motorcycle.

Full Text

The present invention relates to a v-belt type continuously variable transmission. [0001] The present invention relates to a V-belt type continuously variable transmission, and particularly to a V-belt type continuously variable transmission capable of controlling gear ratio with an electrical actuator. [Background Art] [0002] A V-belt type continuously variable transmission having a V-belt wound between a drive pulley connected to a motor such as an engine and a driven pulley connected to a load, and capable of controlling gear ratio by continuously changing the wound diameter of the V-belt on the drive pulley and the driven pulley, is known. In order to change the wound diameter of the V-belt, of fixed pulley,sections and movable pulley sections respectively constituting the drive pulley and the driven pulley, the movable pulley sections are made to move in a supporting axis direction to change a distance between the two fellow pulley sections, thus varying the wound diameter. [0003] For example, a continuously variable transmission in which a movable pulley section is moved by a motor is disclosed in Japanese Patent laid-open No. Hei. 5-44827. This continuously variable transmission has a movable pulley section of a drive pulley linked via a bearing to a slider, and the slider is connected via a gear to a motor. [0004] Gear ratio control is carried out by detecting the running condition of an engine from engine rotation speed, throttle opening amount etc. Whether or not a gear ratio is an appropriate value is detected as position of a movable pulley section, and the motor is feedback controlled based on the detected movable pulley section position. [Patent Document 1] Japanese patent laid-open No. Hei. 5-44827. [Disclosure of the Invention] [Problems to be solved by the Invention] [0005] In the above described continuously variable transmission of the related art, a direct acting variable resistor is used as a sensor for detecting position of the movable pulley section. Specifically, a rod that is displaced in a sliding direction of a slider, tracking the slider, is moved on the variable resistor, and a voltage corresponding to that position is detected as positional information of the movable pulley section. With this detection method, the rod inclines along the movement direction of the slider, with one end of the rod being in contact with the slider and the other end sliding on the variable resistor. Therefore, the detection section is laid out extending completely in the movement direction of the slider, that is, in the axial direction of the drive pulley. Because of this, there is a projecting section in the axial direction of the drive pulley, and the degree of freedom with respect to layout of other adjacent components is reduced. [0006] The present invention has been conceived in view of the above-described problems of the related art, and an object of the invention is to provide a V-belt continuously variable transmission in which a section projecting in the axial direction of the drive pulley is controlled, while a sensor for detecting amount of displacement of a movable pulley is arranged. [Means of Solving the Problems] [0007] The present invention is directed to a V-belt type continuously variable transmission, having a drive pulley driven by an engine and a driven pulley driven by the drive pulley via a V-belt, each pulley respectively comprising a fixed section fixed on a support shaft, and a movable section provided so as to be capable of sliding with respect to the support shaft in the axial direction, the movable section of the drive puller being moved in the axial direction by a motor to vary a distance between the fixed section and the movable section, and the rotational speed of the drive pulley being varied in accordance with the drive pulley as a result of the movable section of the driven pulley sliding according to the variation in distance, wherein each gear of a gear unit for transmitting power of the motor to the movable section of the drive pulley is supported by a shaft arranged parallel to the support shaft of the drive pulley,, one shaft of a plurality of gears constituting the gear unit is used as a sensor output shaft, and there are provided a shaft orthogonal to the sensor output shaft and a rotational sensor connected to a shaft orthogonal to the sensor output shaft. [Effects of the invention] [0008] According to the present invention having the above-described features, since the sensor output shaft rotates according to rotation of the gear unit, the rotation amount corresponds to rotation amount of an output shaft of the gear unit causing displacement of the drive pulley movable section. That is, the rotation amount of the sensor outp.ut shaft is a function of rotation amount of the motor and gear ratio of the gear unit. Accordingly, it is possible to control gear ratio based on output of the rotation sensor. Since the shaft of the rotation sensor is orthogonal to the sensor output shaft, the arranging of members for attaching the rotational sensor in the longitudinal direction of the sensor output shaft is avoided. For example, it is possible to have arrangement of a rotational sensor that is likely to become wide in an extension direction of the shafts of each gear of the gear unit arranged parallel to a crank shaft extending in a widthwise direction of the vehicle, that is, wide in the widthwise direction of the vehicle, along the vehicle width. [Best mode for carrying out the invention] [0009] One embodiment of the present invention will be described in the following with reference to the drawings. [Brief description of the drawings] [0035] FIG. 1 is a front section cross section of a V-belt type continuously variable transmission of one embodiment of the present invention. FIG. 2 is a rear section cross section of a V-belt type continuously variable transmission of one embodiment of the present invention. Fig. 3 is a side elevation of a motorcycle of one embodiment of the'present invention. Fig. 4 is a front elevation of an actuator cover provided in a front section of the continuously variable transmission. Fig. 5 is a cross section showing a wall section of a water pump formed from an actuator cover and a crank case. FIG. 3 is an outward side view of a scooter-type two-wheeled vehicle including the continuously variable transmission of one embodiment of the present invention. In Fig. 3, a vehicle front section 2 and a vehicle rear section 3 of the scooter type vehicle 1 are connected via a low floor section 4, and a skeleton of the vehicle body is made up of a down tube 6 and a main tube 7 extending upwards to the rear from the down tube 6. A seat 8 is arranged above the main tube 7. A storage box for storing a helmet or the like and a fuel tank are provided between the seat 8 and the main tube 7. The seat 8 also acts as a cover for the storage box. [0010] A front end of the down tube 6 is connected to a head pipe 5 provided on the vehicle front section 2. A front fork 12 is axially supported on the head pipe 5 in a rotatable manner. A handle 11 is attached to an upwardly extending section of the front fork 12, and a front wheel 13 is axially supported on a lower end of the front fork 12. An upper part of the handle 11 is covered by a handle cover 33 acting as an instrument board. [0011], A bracket 15 is provided on an upright lower end of the main tube 7, a hanger bracket 18 is connected via a link member 16 to the bracket 15, and the swing unit 17 is supported irt a swingable manner. A rear end of the main tube 7 and a rear end of the swig unit 17 are connected by a rear suspension 22 having a damping member. A single cylinder 4-cycle engine 200 is mounted on a front section of the swing unit 17. A V-belt continuously variable transmission 35 and reduction gears 38 are provided at the rear of the engine 200. A rear wheel 21 is connected to an output shaft (described later) of the reduction gears 38. That is, output of the engine 200 is transmitted to the rear wheel 21 via the V-belt continuously variable transmission 35 and the reduction gears 38. [0012] An intake pipe 23 extending from a cylinder head 32 of the engine 200 is connected to the front section of the swing unit 17. A carburetor 24 and an air cleaner 25 connected to the carburetor 24 are arranged at the intake pipe 23. A main stand 26 for parking is supported on the hanger bracket 18 provided on a crankcase 31 of the swing unit 17. A kick arm 28 is fixed to a kick shaft projecting from a case cover (outer cover) 36 of a transmission 35, and a kick pedal 29 is provided on a tip end of the kick arm 28. [0013] Fig. 1 is a front cross sectional view of a continuously variable transmission, and Fig. 2 is a rear cross sectional view of the continuously variable transmission. In Fig. 1 and Fig. 2, the continuously variable transmission is outwardly made up of a transmission case 40 made up of part of the crankcase 31 of the engine 200, a transmission case cover 401 covering the transmission case 40 from a left side surface of the vehicle, an outer cover 36 further covering the transmission case cover 401 from outside, and a gear drive section cover (hereafter called "actuator cover") 58 incorporated into a front section of the transmission case cover 401 (front section in the traveling direction of the vehicle). [0014] In Fig. 1, the crankshaft 41 of the engine 200 is supported by a bearing 42 provided in the transmission case 40, and by one other bearing (not shown).A part 43 of the crankshaft 41 projecting from the crankcase 40 to an outer side is a support shaft for the drive pulley 45, and is a drive shaft of the continuously variable transmission. [0015] A guide pipe 44 is mounted around the drive shaft 43. The drive pulley 45 is made up of a fixed pulley section 451 provided on a shaft end of the drive shaft 43, and a movable pulley section 452 that can move in the axial direction of the drive shaft 43. A V-belt 100 spanning the driven pulley, described later, is wound around the drive pulley 45. The fixed pulley section 451 is fixed to the drive shaft 43 with a nut 46 screwed on to a threaded section provided on the shaft end of the drive shaft 43.A hub 453 of the movable pulley section 452 is slidably fitted around the guide pipe 44 so that the movable pulley section 452 is capable of moving in the drive shaft direction. [0016] A hole that is elongated 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 section 452.A guide pin 48 is erected on the outer periphery of the guide pipe 44, and a head section 481 of this guide pin 47 projects inside the guide hole 47. A collar 49, such as fluorocarbon resin whose surface has a low coefficient of friction is provided on the head section of the guide pin 48 so as to cover at least part that faces an inner surface of the guide hole 47. Preferably, a part facing the outer periphery of the guide pin 44 is also covered, as shown in the drawing. In this way, the movable pulley section 452 having the fixed hub 453 has displacement in the rotational direction controlled with respect to the guide pipe 44, that is, the drive shaft 43, by the guide pin 48, and is only capable of movement in the axial direction with respect to the drive shaft 43. Since the guide pin 48 sides in the guide hole 47 of the hub 453 via the collar 49, movement of the movable pulley section 452 is smooth, and the generation of sliding noise is suppressed. [0017] A bearing holding ring 50 is fitted around the hub 453 of the movable pulley section 452, and an inner race of a bearing 51 is fitted around this holding ring 50 A slider holding ring 52 is fitted to the outer race of the bearing 51, and a slider 53 is also fitted into this holding ring 52 (50?). The slider 53 is cylindrical, with a near 531 formed on an outer side, with a feed connecting ring 54 having an internal thread (screw thread) formed in the inside being inserted in an inner side. The inside thread of the feed connecting ring 54 is screwed to an external thread formed on the outer periphery of a cylinder 55. The cylinder 55 is fixed to the transmission case 40 with a bolt 56, via a flange section welded to the outside of the cylinder 55. [0018] Next, the drive section for transmitting power to the gear 531 of the slider 53 will be described. The drive section for transmitting drive to the gear 531 of the slider 53 has a gear unit and a motor. The motor 57 is provided with a base plate 571 and a housing 572, with the base plate 571 being inserted into the actuator cover 58 of the transmission case 40 and fixed. An output gear 591 is formed on a tip end of the motor shaft 59. [0019] The gear unit 60 comprises first gears 62, 63 fixed to a common shaft 61, and second gears 65, 66 fixed to another common shaft 64. Each of the gears of the gear unit 60 are preferably made of resin in order to reduce drive noise. The shaft 61 of the first gear is supported by a bearing 67 provided in the transmission case 40 and a bearing 68 provided in 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 gears, a large gear 62 meshed with an output gear 591, while the small gear 63 meshes with the large gear 65 of the second gears. The small gear 66 of the second gears meshes with a gear 531 of the slider 53. [0020] A gear 641 is formed on an extended part of the shaft 64 of the second gears passing through the bearing 70. The gear 641 is a worm gear, and this worm gear 641 meshes with a worm wheel (the rotation sensor and the worm wheel will be described later) connected to a rotation type variable resistor or a rotation type potentiometer, as a rotation sensor. The shaft 64 provides a function as a sensor output shaft for transmitting rotation amount of the gear unit 60 to the rotation sensor. [0021] A rib 402 is formed on the transmission case 40 so as to surround the outer periphery of a gear 531 formed on the slider 53, and a regulating plate 72 is attached to an end of the rib 402 using a bolt 71. The slider 53 has a movement limit towards the drive pulley 45 side regulated by the regulating plate 72. Normally, the gear 531 of the slider 53 moves in a range that does not bring it into contact with the regulating plate 72. [0022] With the above described structure, rotation of the motor 57 is transmitted to the gear 531 of the slider 53 sequentially through the first gears 62, 63, and the second gears 65, 66, and the slider 53 rotates. If the slider 53 rotates, the feed connecting ring 54 rotates around the cylinder 55, and as a result the slider 53 is relatively screw fed in an axial direction of the crank shaft 41. The displacement direction of the slider due to operation of the thread is the direction of the feed connecting ring 54, and the inner and outer threads of the cylinder 55. [0023] If the slider 53 is displaced along the drive shaft 43, that movement is transmitted via the bearing 51 to the movable pulley section 452, and a distance between the movable pulley section 452 and the fixed pulley section 451 is varied. If the distance between the fixed pulley section 451 and the movable pulley section 452 is made wide, the V-belt 100 that is interdependent on movement of a driven pulley, that will be described later, is operated so as to have a small diameter wrapped around the drive pulley 45. On the other hand, as the distance between the fixed pulley section 451 and the movable pulley section 452 is made narrower, a force component pressing the V-belt 100 out in the outward direction of the drive pulley 45 acts, and the V-belt 100 that is interdependent on movement of a driven pulley, that will be described later, is operated so as to have a large wrapping diameter. [0024] The position of the slider 53 represents gear ratio of the transmission. Therefore, the position of the slider 53 is detected by a rotation sensor for detecting rotational position of the worm gear 641, and that detection result can be fed back to gear ratio control. [0025] Next, the rear structure of the continuously variable transmission will be described. In Fig. 2, the driven pulley 73 is made up of the fixed pulley section 731 and the movable pulley section 732. A driven shaft (driven pulley shaft) 74 supporting the driven pulley 73 is supported by bearings 75, 76. A bearing 77 is fitted in to an end section to one side of the driven shaft 74, that is further to the left side than the bearing 75 in Fig. 2, and a side further forward than the bearing 77 is covered by a collar 78. A cube-shaped clutch plate 79 is welded to the collar 78. A thread is formed on this tip section of the driven shaft 74, a nut 80 is screwed onto the thread, and the collar 78 and the clutch plate 79 are fixed to the driven shaft 74 via an inner race of the bearing 77. A bearing 81 is provided on the outer periphery of a middle section of the driven shaft 74, and the hub 82 of the fixed pulley section 731 is mounted on the outer periphery with respect to the driven shaft 74 by the bearing 81 and the bearing 77. [0026] Also, the hub 82 of the movable pulley section 732 is provided on the outer periphery of the fixed pulley section 731. The movable pulley section 732 slides in the longitudinal direction of the driven shaft 74 with respect to the fixed pulley section 731. A guide pin 84 is erected on the hub 82. The guide hole 83 provided in the hub 83 is engaged with a head section of the guide pin 84, and in this way rotation of the movable pulley section 732 with respect to the hub 83 is regulated. [0027] A support plate 85 of a clutch shoe is fixed to an end part of the hub 82 of the fixed pulley section 731 with a nut 86. The clutch shoe 87 is provided on the support plate 85. The clutch shoe 87 is mounted on an arm 90 having a boss 89 supported by a pivot shaft 88 provided in the support plate 85. The arm 90 is urged by a spring 91 in a direction separating the clutch shoe 87 from the clutch plate 79. Also, a coil spring 92 for urging the movable pulley section 732 to the fixed pulley 731 side is fitted between the movable pulley section 732 and the support plate 85. [0028] Reduction gears 38 are provided at the rear of the continuously variable transmission. The reduction gears 38 have an input gear 94, intermediate gears 95, 96, and a final gear 97 provided on another end of the driven shaft 74, that is between the bearing 75 and the bearing 76 in Fig. 2. The input gear 94 meshes with a large gear 95 of the intermediate gears, and the small gear 96 of the intermediate gears meshes with the final gear 97. Shafts of the intermediate gears 95, 96 are supported by bearings 98, 99, and a 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 a rear casing 403 continuing to the rib 402, and the bearings 75, 99 and 102 are fitted into a reduction gear cover 104 fixed to the casing 403. [0029] A sensor plate 105 is provided on the hub 82 side of the fixed pulley section 731, and a magnetic sensor 106 is provided facing the outer periphery of the sensor plate 105 .The sensor plate 105 is made of iron, and this iron sensor plate 105 has from one to a plurality of sections that are projecting to the outside or concave. Therefore, the output of a magnetic senor 106 changes at this shape changing section, and the rotational speed of the driven pulley section 73 can be detected using the state of the change, for example, an interval between output changes. The magnetic sensor 106 is fixed to the reduction gear cover 104. [0030] In the above described structure, if the wound diameter of the V-belt is expanded at the drive pulley 45 side, tension of the V-belt increases, and as a result of that increase in tension a force acts pushing between the movable pulley section 732 and the fixed pulley section 731 of the driven pulley 73. As a result, at the driven side, the V-belt 100 is wound at a small diameter. That is, the gear ratio is small. On the other hand, if the wound diameter of the V-belt is reduced at the drive pulley 45 side, tension of the V-belt 100 is reduced, and as a result of that reduction in tension if the tension force component, that is the urging force of the coil spring 92 acting on the V~belt 100, is raised, a reduction force is generated between the movable pulley section 732 and the fixed pulley section 731 of the driven pulley 73. As a result, at the driven side, the V-belt is wound at a large diameter. That is, the gear ratio is large [0031] If rotation of the driven side pulley 73 reaches a specified value, the clutch shoe 87 comes into contact with the clutch plate 79 due to centrifugal force. If this happens, the driven shaft 74 connected to the clutch plate 79 rotates, and the output shaft 101 will rotate via the input gear 94, intermediate gears 95, 96, and the final gear 97. Rotation of the output shaft 101 is transmitted to the rear wheel 21, and the two-wheeled vehicle can travel. [0032]Fig. 4 is a front elevation of an actuator cover 58 incorporated with a front section of the transmission case, and Fig. 5 is a cross section along line A - A in Fig. 4. The actuator cover 58 covers structural components of the reduction system, from the motor 57 to the shaft 64, as described above, and also acts as a cover of a water pump for circulating engine cooling water. In Fig. 4, a worm wheel 110 meshing with a worm gear 641 supported by a bearing 70 fitted into the actuator cover 58, and a shaft 111 of the worm wheel 110, are housed, and a cylindrical projecting section 581 for supporting the shaft 111 is formed. A rotation sensor 112 for detecting rotational position of the worm wheel 110 is connected to the shaft 111. Detection output of the rotation sensor 112 is. supplied to a controller, not shown, and based on this detection output the position of the movable pulley section 452 is detected via each of the gears 641, 65, 66 and 531 connected to the worm wheel 110. [0033] The actuator cover 58 also has bosses 582 and 583 for holding a base plate 571 of the motor 57, and seats 585, 586 provided adjacent to a boss hole 584 for receiving a hub of the base plate 571 of the motor 57[SB1]. [0034] Further, as will be more clearly understood from Fig. 5, the actuator cover 58 is incorporated into part of the transmission case 40 to form an outer wall of the water pump 113. A space enclosed by this outer wall houses an impeller 114 and a shaft 115. The shaft 115 is connected to an engine using a transmission unit, not shown, and is driven to rotate by rotation of the engine. A mouthpiece 116 is an inlet for cooling water circulated from a radiator via a thermostat, and a mouthpiece 117 is; an inlet for cooling water circulated not via the radiator. From when starting. the engine to when cooling water temperature is low, water is introduced from the mouthpiece 117, and if cooling water temperature reaches a specified value or higher water that has been reduced in temperature via the radiator is introduced from the mouthpiece 116. [Description of the Numerals] [0036] 40 transmission case 41 crankshaft 45 drive pulley 53 slider 57 motor 60 gear unit 73 driven pulley 100 V-belt 110 worm wheel 111 worm wheel shaft 112 rotation sensor 451 drive pulley section 452 movable pulley section WE CLAIM: 1. A V-belt type continuously variable transmission, having: a drive pulley (45) driven by an engine and a driven pulley (73) driven by the drive pulley via a V-belt (100), composing a swing unit for a motorcycle together with the engine, each pulley comprising a fixed section fixed on a support shaft, and a movable section provided so as to be capable of sliding with respect to the support shaft in an axial direction, the moveable section of the drive pulley (45) being displaced in the axial direction by a motor to vary a distance between the fixed section and the movable section, and the rotational speed of the driven pulley being varied in accordance with the drive pulley (45) as a result of the movable section of the driven pulley sliding according to a variation in the distance, wherein a gear unit (60) is provided for transmitting power of the motor (57) to the movable section of the drive pulley, an actuator cover (58) is provided for covering the gear unit (60) by being assembled to an engine output transmission case (40) cover and supporting the motor, a shaft is provided which is arranged in parallel to the support shaft of the drive pulley (45) and which supports each gear of the gear unit (60), the movable section of the drive pulley (45) is arranged near to the inner side of the motorcycle with respect of the fixed section, a rotation sensor (112) is further provided which is connected to a shaft orthogonal to a sensor output shaft as a shaft nearest to the support shaft of the drive pulley (45), of the shafts of a plurality of gears composing the gear unit (60) and which is arranged in front of the sensor output shaft in a side view of the motorcycle, and the shaft orthogonal to the sensor output shaft is stored in a cylindrical projecting portion formed on the actuator cover (58), and also arranged between the sensor output shaft and the motor in the side view of the motorcycle. 2. The V-belt (100) continuously variable transmission as claimed in claim 1, wherein each gear of the gear unit (60) is made of resin. 3. The V-belt (100) continuously variable transmission as claimed in claim 1 or 2, wherein the rotation sensor (112) is a potentiometer.

Documents:

1472-DEL-2004-Abstract-(22-06-2011).pdf

1472-del-2004-abstract.pdf

1472-del-2004-Claims-(22-06-2011).pdf

1472-del-2004-Claims-(27-09-2012).pdf

1472-del-2004-claims.pdf

1472-del-2004-Correspondence Others-(22-06-2011).pdf

1472-del-2004-Correspondence-Others-(27-09-2012).pdf

1472-del-2004-correspondence-others.pdf

1472-del-2004-Description (Complete) (11-01-2008).pdf

1472-del-2004-description (complete).pdf

1472-del-2004-Drawings-(22-06-2011).pdf

1472-del-2004-drawings.pdf

1472-del-2004-Form-1-(22-06-2011).pdf

1472-del-2004-form-1.pdf

1472-del-2004-Form-13-(27-09-2012).pdf

1472-del-2004-form-19.pdf

1472-del-2004-Form-2-(22-06-2011).pdf

1472-del-2004-form-2.pdf

1472-del-2004-Form-3-(22-06-2011).pdf

1472-del-2004-form-3.pdf

1472-del-2004-form-5.pdf

1472-del-2004-GPA-(22-06-2011).pdf

1472-del-2004-GPA-(27-09-2012).pdf

1472-del-2004-gpa.pdf

1472-del-2004-Petition-137-(22-06-2011).pdf

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