JP5866241B2 - Continuously variable transmission for motorcycle - Google Patents

Description

  The present invention relates to a continuously variable transmission for a motorcycle that transmits power by means of a V-belt stretched between pulleys.

  Conventionally, a V-belt is wound between a driven pulley and a driven pulley having a fixed pulley piece fixed to the crankshaft and a movable pulley piece supported so as to be slidable in the axial direction facing the fixed pulley piece. A hung V-belt automatic transmission is known. (For example, refer to Patent Document 1). The V-belt type automatic transmission of Patent Document 1 transmits the power of an electric motor to a movable pulley piece via a gear reduction mechanism and a screw mechanism, and moves it in a direction toward or away from a fixed pulley piece to wind the V-belt. By changing the hanging diameter, the power is continuously variable.

JP 2007-232221 A

  In the V-belt type automatic transmission described in Patent Document 1, the movable pulley piece is moved in the axial direction by the electric motor to change the winding diameter of the V-belt, so that an arbitrary speed change characteristic can be obtained by controlling the electric motor. Can be obtained. However, since an electric motor is used, the transmission mechanism is increased in size, the number of parts is increased, and the manufacturing cost is increased.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a continuously variable transmission for a motorcycle that can improve the degree of freedom of transmission characteristics with a simple and compact mechanism. is there.

In order to achieve the above object, the invention according to claim 1
A drive pulley attached to the drive shaft;
A driven pulley attached to the driven shaft;
A V-belt wound between the driving pulley and the driven pulley;
Have
The driving pulley or the driven pulley is
A fixed pulley piece fixed to the drive shaft or the driven shaft;
A movable pulley piece disposed on the drive shaft or the driven shaft so as to be integrally rotatable with the drive shaft or the driven shaft and movable in a direction approaching or separating from the fixed pulley piece;
A fixed ramp plate fixed to the drive shaft or the driven shaft facing the movable pulley piece;
A first weight roller disposed between the fixed ramp plate and the movable pulley piece and pressing the movable pulley piece by centrifugal force to move the movable pulley piece toward the fixed pulley piece. Continuously variable transmission,
A direction fixed to the movable pulley piece so as to be opposite to the movable pulley piece with respect to the fixed pulley piece, and capable of rotating integrally with the driving shaft or the driven shaft and approaching or separating from the fixed pulley piece. A movable lamp plate movable to
A second weight roller disposed between the fixed pulley piece and the movable ramp plate, and pressing the movable ramp plate by a centrifugal force to move the movable pulley piece in the fixed pulley piece direction;
The drive shaft or the driven shaft is disposed so as to be movable in the axial direction, and is between a prohibition position that prevents movement of the second weight roller due to centrifugal force and an operation position that allows movement of the second weight roller. A movable movable plate;
And a switching mechanism for switching the movable plate to the prohibited position and the operating position .

Invention, in addition to the first aspect according to claim 2,
The switching mechanism is
A locking step portion fixed to the drive shaft or the driven shaft and having an inclined surface inclined in the axial direction, a slide surface inclined in the same direction as the inclined surface of the locking step portion, and continuous to the slide surface A fixed cam formed on the front end surface with an axial groove formed continuously in the circumferential direction;
A movable cam that is disposed between the fixed cam and the movable plate, and has an engagement rib that has a tip end surface inclined in the same direction as the inclined surface of the locking step portion and engageable with the axial groove;
A cam push that is slidably fitted to the fixed cam, and that pushes the engagement rib in the axial direction by a tip surface inclined in the same direction as the inclined surface of the locking step portion;
By engaging the engaging rib of the movable cam with the axial groove of the fixed cam, the movable plate is positioned at the operating position;
The movable plate is positioned at the forbidden position by bringing the engagement rib of the movable cam into contact with the locking step of the fixed cam.

The invention according to claim 3 includes, in addition to the configuration of claim 1 or claim 2 ,
The movable plate includes a protrusion that protrudes toward the movable lamp plate,
When the movable plate is located at the prohibited position, the protrusion penetrates a long hole of the movable lamp plate and contacts the second weight roller to prevent the movement of the second weight roller. To do.

The invention according to claim 4, in addition to the configuration of any one of claims 1 to 3,
The movable lamp plate and the movable plate are spline fitted to the drive shaft or the driven shaft.

The invention according to claim 5 includes, in addition to the configuration of any one of claims 1 to 4 ,
The drive shaft is a crankshaft of an internal combustion engine.

According to the first aspect of the present invention, it is possible to improve the degree of freedom of the speed change characteristics by having both types of weight rollers.
In addition, the speed change mechanism that can be switched between the drive mode and the eco mode can be a simple and compact mechanism, and the number of parts can be suppressed and the manufacturing cost can be reduced.

According to the invention of claim 2 , each time the movable cam is pressed by the cam push, the movable plate can be alternately switched between the operation position and the prohibition position. In addition, the switching mechanism can be simplified and downsized.

According to the invention of claim 3 , the continuously variable transmission can be reliably switched between the eco mode and the drive mode with a simple and compact configuration.

According to the invention of claim 4 , the movable lamp plate and the movable plate rotate synchronously, and the protrusion of the movable plate surely passes through the long hole of the movable lamp plate and contacts the second weight roller. You can touch.

According to the invention of claim 5, the continuously variable transmission is suitable for use in a transmission mechanism of an internal combustion engine.

It is sectional drawing of a power unit provided with the continuously variable transmission which concerns on this invention. (A) is a principal part expanded sectional view of the continuously variable transmission which operate | moves in eco mode, (b) is a figure which shows the state of the plate cam of (a). It is a principal part side view of FIG. It is a disassembled perspective view of a switching mechanism. It is explanatory drawing explaining the switching procedure of a switching mechanism. It is a principal part expanded sectional view of the continuously variable transmission which operate | moves in drive mode, (b) is a figure which shows the state of the plate cam of (a).

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.

  FIG. 1 is a cross-sectional view of a power unit including a continuously variable transmission according to the present invention. FIG. 2 is an enlarged cross-sectional view of a main part of a continuously variable transmission operating in an eco mode. In FIG. 1, Fr represents the front, Re represents the rear, L represents the left, and R represents the right. As shown in FIG. 1, the power unit P is mounted on a motorcycle, and is provided on the front side of the rear wheel WR, on one side in the vehicle width direction from the internal combustion engine 20, and on the rear side. The V-belt type continuously variable transmission 10 extending in the vertical direction and the reduction gear mechanism 110 provided at the rear of the V-belt type continuously variable transmission 10 are mainly configured.

  The internal combustion engine 20 is, for example, a 4-cycle 1-cylinder internal combustion engine, and includes a unit case 21 including a right unit case 21a, a middle unit case 21b, and a left unit case 21c, a cylinder block 22, a cylinder head (not shown), and A cylinder head cover.

  A crankshaft 25 is rotatably supported by a pair of rolling bearings 31 in the unit case 21. An AC generator 26 having a rotor 26a and a stator 26b is fixed to the right end of the crankshaft 25, and a case cover 27 covers the sides thereof.

  A piston 29 that reciprocates in the cylinder sleeve 28 of the cylinder block 22 is connected to a crankpin of the crankshaft 25 via a connecting rod 30. A combustion chamber is formed on the lower surface of the cylinder head facing the top surface of the piston 29, and a spark plug (not shown) is attached.

  A timing chain is wound between a cam chain sprocket (not shown) fitted to the right end of a cam shaft disposed in the cylinder head and a drive chain sprocket 34 fixed to the crankshaft 25 to The rotation of the shaft 25 is reduced to 1/2 and transmitted to the camshaft, and the intake valve and the exhaust valve are opened and closed at a predetermined timing via the intake rocker arm and the exhaust rocker arm.

  The V-belt type continuously variable transmission 10 is wound between a drive pulley 60 attached to a crankshaft 25 that is a drive shaft, a driven pulley 93 attached to a driven shaft 92, and between the drive pulley 60 and the driven pulley 93. And a V-belt 95 that is hung. The V-belt type continuously variable transmission 10 is disposed in a power transmission chamber 40 covered with a middle unit case 21b and a left unit case 21c.

  2 and 3, the V-belt type continuously variable transmission 10 has a small-diameter shaft portion 25a on the left side of the crank portion of the crankshaft 25, and a screw portion 51 is formed at the left end of the small-diameter shaft portion 25a. Yes. The small-diameter shaft portion 25a is fitted with a fixed ramp plate 52 that contacts the step portion 25b of the crankshaft 25 and a spline sleeve 53 provided with a male spline 53a on the outer peripheral surface. The fixed ramp plate and the spline sleeve 53 is fixed to the crankshaft 25 by being tightened by screwing the nut 54 into the threaded portion 51. In addition, a fixed pulley piece 61 is integrally fixed at substantially the center in the axial direction of the small diameter shaft portion 25a.

  The spline sleeve 53 is fitted with a movable pulley shaft 62 that passes through a hole 61 a formed in the fixed pulley piece 61 and moves in the axial direction. A female spline 62 a is formed on the inner peripheral surface of the movable pulley shaft 62 and is engaged with the male spline 53 a of the spline sleeve 53. Thereby, the movable pulley shaft 62 can rotate integrally with the crankshaft 25 (spline sleeve 53) and can slide in the axial direction.

  A movable pulley piece 63 is fixed to one end (right end in FIG. 2) of the movable pulley shaft 62 on the fixed ramp plate 52 side so as to face the fixed pulley piece 61. The fixed pulley piece 61 and the movable pulley piece 63 constitute a drive pulley 60. A movable lamp plate 64 is fixed to the other end (left end in FIG. 2) of the movable pulley shaft 62 on the back side of the fixed pulley piece 61. Therefore, the movable pulley piece 63 and the movable ramp plate 64 can rotate integrally with the crankshaft 25 together with the movable pulley shaft 62 and can slide in the axial direction. That is, the movable pulley piece 63 is disposed between the fixed ramp plate 52 and the fixed pulley piece 61, and the movable ramp plate 64 is positioned on the opposite side of the movable pulley piece 63 with respect to the fixed pulley piece 61. At three locations on the outer peripheral surface of the movable lamp plate 64, fitting pieces 69 that are fitted to three ribs 61b extending in the axial direction formed on the inner peripheral surface of the fixed pulley piece 61 are attached. The movable lamp plate 64 is configured to be guided by the fixed pulley piece 61 to slide in the axial direction.

A plurality (three in this embodiment) of first weight rollers 65 are arranged between the fixed ramp plate 52 and the movable pulley piece 63. When the crankshaft 25 rotates, the first weight roller 65 moves radially outward by centrifugal force to press the movable pulley piece 63, and the movable pulley piece 63 moves in the direction of the fixed pulley piece 61 (left direction in the figure). Let The force with which the first weight roller 65 presses the movable pulley piece 63 is proportional to the rotational speed of the crankshaft 25.
A fitting piece 59 for fitting with the movable pulley piece 63 is also attached to the outer peripheral surface of the fixed ramp plate 52, and the sliding of the movable pulley piece 63 in the axial direction is guided by the fixed ramp plate 52. Yes.

  A plurality (three in this embodiment) of second weight rollers 66 are arranged between the fixed pulley piece 61 and the movable ramp plate 64. When the crankshaft 25 rotates, the second weight roller 66 moves radially outward by centrifugal force to press the movable ramp plate 64, and the movable pulley piece 63 is moved toward the fixed pulley piece 61 via the movable pulley shaft 62 ( Move to the left in the figure. The force with which the second weight roller 66 presses the movable ramp plate 64 is proportional to the rotational speed of the crankshaft 25. The second weight roller 66 is formed with a smaller diameter than the first weight roller 65.

  Further, the movable plate 67 arranged on the axially outer side (left side) of the movable lamp plate 64 has a female spline 67c formed on the inner diameter surface spline-fitted with the male spline 53a of the spline sleeve 53, and is thus subjected to centrifugal force. The second weight roller 66 can be slidably moved in the axial direction between a prohibited position (see FIG. 6) for preventing the movement of the second weight roller 66 and an operating position (see FIG. 2) for allowing the movement of the second weight roller 66. Yes.

  The movable plate 67 is a substantially disk-shaped member, and is formed with three plate-like protrusions 67 a that protrude toward the movable lamp plate 64. As shown in FIG. 6, the plate-like protrusion 67a passes through a long hole 64a (see FIG. 3) formed in the movable lamp plate 64 when the movable plate 67 moves in the direction of the fixed pulley piece 61. It contacts the weight roller 66. A plurality of cooling fins 67 b that generate cooling air are provided on the opposite side of the plate-like protrusions 67 a of the movable plate 67. Further, a seal member 89 that slidably contacts the outer peripheral surface of the cam push 73 is attached to a cylindrical portion inside the cooling fin 67 b of the movable plate 67.

  Thus, since the movable plate 67 and the movable ramp plate 64 are spline-fitted to the same spline sleeve 53, the relative phase is always constant, and the movable plate 67 moves in the direction of the fixed pulley piece 61. The plate-like protrusion 67a surely passes through the long hole 64a of the movable lamp plate 64. A retaining ring 74 is provided on the outer peripheral surface of the spline sleeve 53 between the movable plate 67 and the movable ramp plate 64. The retaining ring 74 restricts movement of the movable pulley shaft 62 in the axial direction, and a compression coil spring 68 is disposed between the retaining ring 74 and the movable plate 67. The compression coil spring 68 presses the movable plate 67 in the left direction.

  A switching mechanism 70 is disposed at the left end of the crankshaft 25 to move the movable plate 67 between the prohibition position and the operation position. Referring to FIG. 4 as well, the switching mechanism 70 is externally fitted to the fixed cam 71 fixed to the crankshaft 25 and the spline sleeve 53 so as to be slidable and rotatable in the axial direction. A movable cam 72 disposed between the plate 67 and a cam push 73 fitted on the fixed cam 71 so as to be slidable in the axial direction.

  On the distal end surface of the fixed cam 71, there are a locking step portion 75 inclined in the axial direction, a slide surface 76 inclined in the same direction as the locking step portion 75, and an axial groove 77 in this order in the circumferential direction. It is formed continuously. In the embodiment shown in FIG. 4, four sets of the locking step 75, the slide surface 76, and the axial groove 77 are repeatedly formed in the circumferential direction. That is, four sets of the locking step 75, the slide surface 76, and the axial groove 77 are formed with a 90 ° phase.

  The movable cam 72 includes four engagement ribs 78 that are formed at the same 90 ° intervals as the axial groove 77 of the fixed cam 71 and can be engaged with the axial groove 77. The front end surface 78a of the engagement rib 78 is inclined in the same direction as the locking step 75 (slide surface 76). The movable cam 72 moves in the axial direction together with the movable plate 67, and is positioned at the prohibition position where the plate-like protrusion 67a of the movable plate 67 contacts the second weight roller 66 and the operation position where the corresponding contact is released. .

  The cam push 73 has eight sets of triangular cam ridges 79 formed in the circumferential direction on the tip surface. One inclined surface of the cam crest 79 is an inclined surface 79a inclined in the same direction as the locking step portion 75, and the shape of the other inclined surface is not particularly limited as long as the inclined surface 79a can be formed. The cam push 73 and the fixed cam 71 are relatively movable in the axial direction while maintaining the circumferential phase in the same phase. The phase of the top portion 79 b of each cam crest 79 substantially coincides with the phases of the locking step portion 75 and the axial groove 77 of the fixed cam 71. On the radially inner side of the cam push 73, a coil spring 88 is accommodated so as to abut on the axial side surface of the fixed cam 71 and the axial side surface of the cam push 73. Is energized to the left. The cam push 73 is rotatably supported by a bowl-shaped operation member 81 via a ball bearing 80 provided on the inner peripheral surface.

  A ball 86 urged by a spring 87 is disposed at the center of the operation member 81, and the ball 86 is disposed opposite to the center of the operation member 81, and a plate cam 83 fixed to the cam shaft 82. It is in contact. The cam shaft 82 is rotationally driven by a wire 85 wound around a pulley 84. When the plate cam 83 presses the operating member 81 via the ball 86 and moves in the axial direction by the rotation of the cam shaft 82, the operating member 81 moves the cam push 73 in the axial direction. Thereby, the cam crest 79 of the cam push 73 presses the front end surface 78a of the engagement rib 78 to move the engagement rib 78 in the axial direction (right direction). At this time, every time the cam push 73 presses the movable cam 72 in the axial direction by the cam action of the cam crest 79 (inclined surface 79a) of the cam push 73 and the tip end surface 78a in which the engagement rib 78 is inclined, the movable cam 72 72 rotates by a predetermined angle, and the engagement rib 78 repeatedly engages with the axial groove 77 of the fixed cam 71 and abuts with the locking step 75. When the movable plate 67 is located at the prohibition position and the operation position, the ball 86 is fitted into the cam grooves 83 a and 83 b of the plate cam 83.

  When the engaging rib 78 of the movable cam 72 is engaged with the axial groove 77 of the fixed cam 71, the switching mechanism 70 is the total axial length of the movable cam 72 and the fixed cam 71, that is, the switching mechanism 70. And the movable plate 67 is positioned at the operating position (FIG. 2). Further, when the engaging rib 78 of the movable cam 72 comes into contact with the locking step portion 75 of the fixed cam 71, the axial length of the switching mechanism 70 becomes longer and the movable plate 67 is positioned at the prohibited position (FIG. 6). ). Details of the operation will be described later.

  Returning to FIG. 1, a driven shaft 92 is pivotally supported via a pair of ball bearings 91 at a rear portion of the power transmission chamber 40 surrounded by the middle unit case 21 b and the left unit case 21 c. Yes. A driven pulley 93 of the V-belt type continuously variable transmission 10 is rotatably fitted to the driven shaft 92, and a centrifugal clutch 94 is disposed on one side in the vehicle width direction.

  The driven pulley 93 includes a fixed pulley piece 93a and a movable pulley piece 93b. The fixed pulley piece 93a is fixed to one end (right end) of a sleeve 96 that is rotatably fitted to the driven shaft 92. The movable pulley piece 93 b is rotatably fitted on the sleeve 96 and is urged toward the fixed pulley piece 93 a by the spring force of the compression coil spring 97. A clutch shoe 98 having a friction member provided on the outer peripheral surface is fixed to the other end (left end) of the sleeve 96. Further, a saddle type clutch outer 99 is spline-fitted to the driven shaft 92 with its inner side facing the clutch shoe 98.

  When the driven pulley 93 rotates at a rotational speed greater than a predetermined rotational speed, the clutch shoe 98 swings radially outward by centrifugal force against the spring force of the clutch spring 101, and each clutch shoe 98. The friction member provided on the outer peripheral surface of the clutch contacts the inner peripheral surface of the clutch outer 99, the centrifugal clutch 94 is brought into a connected state, and the rotation of the driven pulley 93 is transmitted to the driven shaft 92.

  A reduction gear mechanism 110 is assembled to the driven shaft 92. A spur gear 111 is provided on the right side of the driven shaft 92. An intermediate shaft 114 having a large diameter gear 112 and a small diameter gear 113 is rotatably supported by a ball bearing 115 in the power transmission chamber 40. Further, an axle 117 having a drive gear 116 is pivotally supported via a pair of ball bearings 118. As a result, in the reduction gear mechanism 110, the driving force transmitted to the spur gear 111 of the driven shaft 92 is transmitted to the large-diameter gear 112 that meshes, and further transmitted to the driving gear 116 that meshes with the small-diameter gear 113. 117 is driven. A wheel 120 of the rear wheel WR is attached to the axle 117.

  In the motorcycle configured as described above, the rotation of the internal combustion engine 20 is transmitted to the rear wheel WR via the V-belt type continuously variable transmission 10, the centrifugal clutch 94, the reduction gear mechanism 110, and the axle 117.

  Next, the operation of the present embodiment having the above configuration will be described with reference to FIGS. First, in both the eco mode and the drive mode, when the crankshaft 25 is not rotating, in the drive pulley 60, the first weight roller 65 and the second weight roller 66 are located radially inward and movable. The pulley piece 63 is positioned away from the fixed pulley piece 61, and the winding radius of the V belt 95 is small. On the other hand, in the driven pulley 93, the movable pulley piece 93b urged by the compression coil spring 97 is located close to the fixed pulley piece 93a, the winding radius of the V-belt 95 is large, and a large gear ratio is obtained. Is set.

  In the eco mode operation state shown in FIG. 2, as shown in FIG. 5A, in the switching mechanism 70, the engaging rib 78 of the movable cam 72 is engaged with the axial groove 77 of the fixed cam 71. The axial length is short. That is, the movable plate 67 is moved to the left in the figure by the spring force of the compression coil spring 68 and is located at an operating position separated from the movable ramp plate 64 (second weight roller 66).

  In this eco mode operation state, when the rotational speed of the crankshaft 25 increases, the first weight roller 65 and the second weight roller 66 move radially outward in the drive pulley 60 by centrifugal force. Thereby, the first weight roller 65 moves the movable pulley piece 63 in the direction of the fixed pulley piece 61 (left direction in the figure). At the same time, the second weight roller 66 presses the movable ramp plate 64 in the left direction in the drawing, and moves the movable pulley piece 63 toward the fixed pulley piece 61 via the movable pulley shaft 62. As described above, the first weight roller 65 and the second weight roller 66 cooperate to move the movable pulley piece 63 toward the fixed pulley piece 61, and the winding radius of the V-belt 95 is increased.

  That is, since the force due to the centrifugal force of the first weight roller 65 and the second weight roller 66 acts on the movable pulley piece 63 at the same time, the axial force is applied to the movable pulley piece 63 from the stage where the rotational speed of the crankshaft 25 is low. Acting, the movable pulley piece 63 moves in the direction of the fixed pulley piece 61 to start shifting. In the driven pulley 93, the movable pulley piece 93b is separated from the fixed pulley piece 93a against the spring force of the compression coil spring 97, and the winding radius of the V belt 95 is reduced. Thereby, a gear ratio becomes small. As described above, the shift is started from the stage where the rotation speed of the crankshaft 25 is low, and the shift speed is fast. Therefore, if the vehicle speed is the same, the rotation speed of the internal combustion engine 20 can be reduced, and the fuel consumption is reduced in the eco mode. You can drive.

  Switching from the eco mode shown in FIG. 2 to the drive mode shown in FIG. 6 is performed as follows. First, the cam shaft 82 is rotated by the operation of the wire 85, and the operation member 81 is pressed by the plate cam 83 via the ball 86 to move the cam push 73 in the axial direction (right direction). As a result, the top portion 79b of the cam crest 79 of the cam push 73 comes into contact with the front end surface 78a of the engaging rib 78 of the movable cam 72 engaged with the axial groove 77 as shown in FIG. The movable cam 72 is moved in the axial direction (right direction in the figure). Then, when the engagement rib 78 gradually comes out of the axial groove 77 and the engagement between the engagement rib 78 and the axial groove 77 is released, the movable cam 72 is guided to the inclined surface 79a of the cam push 73, The engagement rib 78 is slightly rotated until it comes into contact with the valley of the cam peak 79 (see FIG. 5B). Thereby, the engagement rib 78 and the latching step part 75 overlap in the circumferential direction.

  Here, when the cam shaft 82 is further rotated and the ball 86 is fitted into the cam groove 83a of the plate cam 83, the movable cam 72 moves to the left in the drawing as shown in FIG. The leading end surface 78 a of the engagement rib 78 contacts the locking step portion 75 of the fixed cam 71. Then, the movable cam 72 is guided by the inclination of the locking step portion 75, and is further rotated and stopped until the engagement rib 78 contacts the step portion of the locking step portion 75 and the slide surface 76 of the fixed cam 71. To do. As a result, the switching mechanism 70 is in an extended state in which the engaging rib 78 of the movable cam 72 and the locking step 75 of the fixed cam 71 are in contact with each other. At this time, as shown in FIG. 6, the movable plate 67 is pressed by the movable cam 72 and moves to the right, and the plate-like protrusion 67 a passes through the long hole 64 a of the movable lamp plate 64 and the second weight roller. 66 is located at a forbidden position where it abuts 66.

  As shown in FIG. 6, the movable plate 67 in the forbidden position abuts on the second weight roller 66 and prevents the movement of the second weight roller 66 due to centrifugal force, so that the movable plate 67 is movable when the crankshaft 25 rotates. The force for moving the pulley piece 63 in the direction of the fixed pulley piece 61 is only the force due to the centrifugal force of the first weight roller 65. Therefore, the speed change of the crankshaft 25 is required for the speed change as compared with the eco mode in which the first weight roller 65 and the second weight roller 66 work in cooperation. As a result, if the vehicle speed is the same, the rotational speed of the internal combustion engine 20 is increased, and a drive mode is obtained in which high output torque is obtained.

  Further, switching from the drive mode shown in FIG. 6 to the eco mode shown in FIG. 2 again causes the cam push 73 to move in the axial direction via the operation member 81 by the plate cam 83, and the cam crest 79 of the cam push 73 At the top 79b, the engaging rib 78 of the movable cam 72 that is in contact with the locking step 75 is pressed to move the movable cam 72 in the axial direction. Eventually, when the engagement rib 78 exceeds the apex of the slide surface 76 of the fixed cam 71, the movable cam 72 is guided by the inclined surface 79 a of the cam push 73, and the engagement rib 78 contacts the valley of the cam peak 79. The engagement rib 78 and the slide surface 76 overlap in the circumferential direction (see FIG. 5D).

  Then, when the ball 86 is fitted into the cam groove 83b of the plate cam 83 again, the tip surface 78a of the engagement rib 78 comes into contact with the slide surface 76 of the fixed cam 71 as shown in FIG. The movable cam 72 is rotated by being guided by the slide surface 76, and as shown in FIG. 5A, the engaging rib 78 is engaged with the axial groove 77, and the axial length of the switching mechanism 70 is short. Become. As a result, the movable plate 67 in the prohibited position moves to the left by the spring force of the compression coil spring 68 and is positioned in the operating position, and the restraint of the second weight roller 66 is released and the eco-mode is switched.

  Thereafter, similarly, each time the operating member 81 is pressed in the axial direction by the plate cam 83, the movable plate 67 is alternately placed between the operating position and the prohibiting position and switched between the eco mode and the drive mode.

  Since the cam push 73 is separated from the movable cam 72 except at the time of switching, the ball bearing 80 disposed between the cam push 73 and the operation member 81 includes a coil spring 88 and a spring 87. The thrust force does not work.

  As described above, according to the continuously variable transmission 10 for a motorcycle according to the present embodiment, the fixed pulley piece 61 fixed to the crankshaft 25 and the movable pulley 61 can move in a direction approaching or separating from the fixed pulley piece 61. The movable pulley piece 63, the fixed ramp plate 52 fixed to the crankshaft 25 opposite the movable pulley piece 63, and the movable ramp fixed to the movable pulley piece 63 on the opposite side of the fixed pulley piece 61 from the movable pulley piece 63. A plate 64, a first weight roller 65 disposed between the fixed ramp plate 52 and the movable pulley piece 63, a second weight roller 66 disposed between the fixed pulley piece 61 and the movable ramp plate 64, Therefore, the first and second weight rollers 65 and 66 having different characteristics can be provided together, and the degree of freedom of the speed change characteristics can be improved.

  In addition, a movable plate 67 that can move between a prohibition position that prevents the movement of the second weight roller 66 and an operation position that permits the movement, and a switching mechanism 70 that switches the movable plate 67 to the prohibition position and the operation position. Therefore, the speed change mechanism that can be switched between the drive mode and the eco mode can be made a simple and compact mechanism without using a complicated electronic mechanism, and the manufacturing cost can be reduced by suppressing the number of parts. Can be reduced.

  Further, the switching mechanism 70 includes a fixed cam 71 having a locking step 75, a slide surface 76, and an axial groove 77 formed on the tip surface, and an engagement rib 78 engageable with the axial groove 77. A movable cam 72 disposed between the fixed cam 71 and the movable plate 67; and a cam push 73 that slidably fits the fixed cam 71 and presses the engagement rib 78. Since the movable plate 67 is positioned at the operating position by engaging with the axial groove 77, and the movable plate 67 is positioned at the prohibited position by bringing the engaging rib 78 into contact with the locking step portion 75. Each time the movable cam 72 is pressed by the cam push 73, the movable plate 67 can be switched alternately between the operating position and the prohibited position. Moreover, the structure of the switching mechanism 70 can be simplified and reduced in size.

  Further, the movable plate 67 includes a protrusion 67a protruding in the direction of the movable lamp plate 64. When the movable plate 67 is located at the prohibition position, the protrusion 67a abuts against the second weight roller 66 to prevent the movement of the second weight roller 66. Therefore, the continuously variable transmission 10 can be reliably switched between the eco mode and the drive mode with a simple and compact configuration.

  In addition, since the movable lamp plate 64 and the movable plate 67 are spline-fitted to the same crankshaft 25 and rotated synchronously, the protrusion 67a of the movable plate 67 is surely fitted into the elongated hole 64a of the movable lamp plate 64. And can contact the second weight roller 66.

  Since the drive shaft is the crankshaft 25 of the internal combustion engine 20, the continuously variable transmission 10 is suitable for use in the transmission mechanism of the internal combustion engine 20.

  In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.

10 Belt type continuously variable transmission (motorcycle continuously variable transmission)
20 Internal combustion engine 25 Crankshaft (drive shaft)
52 fixed ramp plate 60 driving pulley 61 fixed pulley piece 63 movable pulley piece 64 movable ramp plate 64a elongated hole 65 first weight roller 66 second weight roller 67 movable plate 67a protrusion 70 switching mechanism 71 fixed cam 72 movable cam 73 cam push 75 Locking step 76 Slide surface 77 Axial groove 78 Engaging rib 79 Cam crest 79a Inclined surface (tip surface)
92 Driven shaft 93 Driven pulley 95 V belt

Claims (5)

A drive pulley (60) attached to the drive shaft (25);
A driven pulley (93) attached to the driven shaft (92);
A V-belt (95) wound between the drive pulley (60) and the driven pulley (93);
Have
The driving pulley (60) or the driven pulley (93) is
A fixed pulley piece (61) fixed to the drive shaft (25) or the driven shaft (92);
The drive shaft (25) or the driven shaft (92) can be rotated together with the drive shaft (25) or the driven shaft (92) and can move in a direction approaching or separating from the fixed pulley piece (61). A movable pulley piece (63) disposed on
A fixed ramp plate (52) fixed to the drive shaft (25) or the driven shaft (92) opposite the movable pulley piece (63);
It is arranged between the fixed ramp plate (52) and the movable pulley piece (63), and the movable pulley piece (63) is pressed by a centrifugal force so that the movable pulley piece (63) is fixed to the fixed pulley piece (61). ) First weight roller (65) moved in the direction;
A continuously variable transmission (10) for a motorcycle comprising:
The drive pulley (25) or the driven shaft (92) is fixed to the movable pulley piece (63) so as to be opposite to the movable pulley piece (63) with respect to the fixed pulley piece (61). A movable ramp plate (64) that can rotate together with the fixed pulley piece (61) and move in a direction approaching or separating from the fixed pulley piece (61).
The movable pulley plate (61) is disposed between the fixed pulley piece (61) and the movable ramp plate (64), and the movable ramp plate (64) is pressed by a centrifugal force so that the movable pulley piece (63) is fixed to the fixed pulley piece (61). ) Second weight roller (66) moved in the direction;
A prohibition position that is disposed on the drive shaft (25) or the driven shaft (92) so as to be axially movable and prevents movement of the second weight roller (66) due to centrifugal force, and the second weight roller (66 ) A movable plate (67) movable between operating positions allowing movement of
A continuously variable transmission (10) for a motorcycle, further comprising a switching mechanism (70) for switching the movable plate (67) to the prohibited position and the operating position . The switching mechanism (70)
A locking step (75) fixed to the drive shaft (25) or the driven shaft (92) and having an inclined surface inclined in the axial direction, and in the same direction as the inclined surface of the locking step (75) An inclined slide surface (76) and an axial groove (77) formed continuously in the slide surface (76) are fixed cam (71) formed in the tip surface continuously in the circumferential direction. ,
It is disposed between the fixed cam (71) and the movable plate (67), and the tip end surface is inclined in the same direction as the inclined surface of the locking step (75), and is engaged with the axial groove (77). A movable cam (72) with mating engagement ribs (78);
The engagement rib (78) is moved in the axial direction by a front end surface (79a) that is slidably fitted to the fixed cam (71) and inclined in the same direction as the inclined surface of the locking step (75). A cam push (73) for pressing,
By fitting the engagement rib (78) of the movable cam (72) into the axial groove (77) of the fixed cam (71), the movable plate (67) is positioned at the operating position,
The movable plate (67) is positioned at the prohibited position by bringing the engaging rib (78) of the movable cam (72) into contact with the locking step (75) of the fixed cam (71). CVT motorcycle according to claim 1, wherein (10). The movable plate (67) includes a protrusion (67a) protruding toward the movable lamp plate (64),
When the movable plate (67) is positioned at the forbidden position, the protrusion (67a) passes through the long hole (64a) of the movable lamp plate (64) and comes into contact with the second weight roller (66). the second weight roller (66) moves, characterized in that blocking of claim 1 or claim 2 CVT motorcycle according to (10). Said movable ramp plate (64) and said movable plate (67), said drive shaft (25) or any one of claims 1 to 3, characterized in that the splines to the driven shaft (92) A continuously variable transmission (10) for a motorcycle according to the item. The continuously variable transmission (10) for a motorcycle according to any one of claims 1 to 4 , wherein the drive shaft (25) is a crankshaft (25) of an internal combustion engine (20). ).

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