JP2010203484A - V-belt type continuously variable transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce bearing pressure acting on a torque transmission surface between a pulley shaft and a movable pulley. <P>SOLUTION: A V-belt type continuously variable transmission includes a groove width variable mechanism 80 for changing a groove width of a pulley 60 by sliding the movable pulley 62 along a support part 51b in the pulley shaft 51, and includes a torque transmission part 110 relatively nonrotatably arranged to the pulley shaft, a boss part 63 arranged in the movable pulley 62 and transmitting torque between the torque transmission part 110 and itself, a flange part 111 arranged in the torque transmission part 110 and extending in the radial direction of the pulley shaft, and an axial directional part 112 integrally arranged in the flange part 111. The axial directional part 112 is positioned outside in the radial direction more than an opposed surface 63a with the support part 51b of the movable pulley 62. A synthetic resin shock absorbing member 66 is arranged between the axial directional part 112 and the torque transmission surface in the boss part 63. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a V-belt type continuously variable transmission.

  Conventionally, as seen in, for example, Patent Document 1 (FIGS. 2 to 4), as a V-belt continuously variable transmission, a drive pulley (47) supported by a primary shaft (11) that is a first pulley shaft; , A driven pulley (52) supported by a secondary shaft (50), which is a second pulley shaft, and a V-belt (55) spanned between the driving pulley (47) and the driven pulley (52) The groove width of the pulley (47) is changed by sliding the movable pulley (movable half 49) in the drive pulley (47) in the axial direction along the support portion of the movable pulley (49) in the pulley shaft (11). A V-belt type continuously variable transmission having a groove width variable mechanism is known.

JP 2006-153057 A

In the conventional V-belt type continuously variable transmission described above, as shown in FIGS. 3 and 4 of Patent Document 1, torque transmission between the pulley shaft (11) and the movable pulley (49) 49) through spline coupling between the inner peripheral surface of the boss portion (49B) in 49) and the outer peripheral surface of the support portion of the movable pulley (49) in the pulley shaft (11).
That is, since torque transmission is performed on the inner surface side of the movable pulley boss portion, there is a problem that a force per unit area acting on the torque transmission surface (this force is referred to as surface pressure in the present specification and the like) increases. there were.
An object of the present invention is to provide a V-belt continuously variable transmission that solves the above-described problems and can reduce the surface pressure acting on the torque transmission surface between the pulley shaft and the movable pulley.

In order to achieve the above object, a V-belt continuously variable transmission according to the present invention includes a drive pulley supported by a primary shaft that is a first pulley shaft and a driven shaft supported by a secondary shaft that is a second pulley shaft. Sliding a pulley, a V-belt stretched between the drive pulley and the driven pulley, and a movable pulley in the drive pulley and / or the driven pulley in the axial direction along a support portion of the movable pulley on the pulley shaft. A V-belt type continuously variable transmission equipped with a variable groove width mechanism for changing the groove width of the pulley,
The movable pulley includes a boss portion supported by the pulley shaft;
The boss portion is provided with a sliding portion that supports the movable pulley so as to be movable in the pulley shaft direction, and a torque-transmitted portion that transmits the torque of the pulley shaft, spaced apart in the radial direction of the pulley shaft. It is characterized by that. In the present application, the term “pulley shaft” means the first and / or second pulley shaft.
According to this V-belt type continuously variable transmission, sliding in the axial direction of the pulley and torque transmission are performed separately in the radial direction, thereby reducing stress concentration while avoiding an increase in the size of the boss portion, and a movable pulley. The sliding and torque transmission can be improved.
That is, when transmitting torque of the same magnitude, the surface pressure acting on the torque transmission surface can be reduced as compared with the conventional case. The reduction of the surface pressure can contribute to the miniaturization of the torque transmission part and, consequently, the miniaturization of the entire V-belt continuously variable transmission.
Preferably, the torque receiving part of the boss part is engaged with a torque transmitting part provided so as not to rotate relative to the pulley shaft to transmit the torque of the pulley shaft to the movable pulley.
The torque transmitting part and the torque-transmitted part are configured to be relatively movable along the axial direction of the pulley shaft and to transmit torque by abutting in the rotational direction of the pulley shaft.
If comprised in this way, even if a torque transmission part and a to-be-torque transmission part move relatively with the movement of a movable pulley, the torque of a pulley axis | shaft can be transmitted.
Preferably, the pulley shaft has a large-diameter portion and a small-diameter portion that is provided on the large-diameter portion via a step portion and constitutes a support portion of the movable pulley,
The torque transmission portion is a member separate from the pulley shaft, and has a flange portion extending in a radial direction of the pulley shaft and the axial portion integrally provided on the flange portion. The flange portion is inserted between the boss portion of the movable pulley and sandwiched between the end portion of the cylindrical member attached to the small diameter portion of the pulley shaft and the stepped portion, so that the relative rotation with respect to the pulley shaft is impossible. It is set as the structure fixed to.
If comprised in this way, it will become easy to produce compared with the case where a torque transmission part is integrally formed in a pulley axis | shaft, and it will become possible to fix a torque transmission part reliably with respect to a pulley axis | shaft so that relative rotation is impossible. .
Desirably, a buffer member made of synthetic resin is provided between the axial direction portion of the torque transmitting portion and the torque transmitting surface of the boss portion.
If comprised in this way, a movable pulley can be smoothly moved, making the grease supply to a torque transmission surface unnecessary.
Preferably, a plurality of engaging portions of the torque transmitting portion are provided around the axis.
With this configuration, torque can be transmitted more smoothly, and the surface pressure can be more reliably reduced.
Desirably, an engaging member is disposed on the outer periphery of the boss portion of the movable pulley via a bearing for sliding the movable pulley.
If comprised in this way, it will become possible to comprise compactly the power transmission system for sliding a movable pulley. Moreover, wear of the anchor member can be prevented by shortening the axial length and preventing the torque from being transmitted to the engaging member.

The side view which shows the scooter type motorcycle as an example using one Embodiment of the V-belt type continuously variable transmission which concerns on this invention. FIG. 3 is a side view of a power unit including a V-belt type continuously variable transmission in the motorcycle. Partial omission III-III sectional drawing in FIG. The elements on larger scale of FIG. FIG. 4 is a partially omitted V arrow view in FIG. 3. FIG. 3 is an exploded perspective view showing a main part of a torque transmission unit 110.

Embodiments of a V-belt type continuously variable transmission according to the present invention will be described below with reference to the drawings.
FIG. 1 is a side view showing a scooter-type motorcycle as an example using an embodiment of a V-belt continuously variable transmission according to the present invention, and FIG. 2 shows a V-belt continuously variable transmission in the motorcycle. FIG. 3 is a partially omitted III-III sectional view in FIG.
As shown in FIG. 1, this motorcycle 10 is a vehicle in which a power unit 20 is suspended from a body frame 11 around a pivot shaft 12 by a pivot shaft 12 and a rear cushion unit 13 at a rear portion of the body frame 11. It is. A front fork 14 is attached to the head pipe 11h so as to be steerable, and a front wheel 15F is attached to the lower end of the front fork 14. A steering handle 15 is attached to the top of the front fork 14.
The body frame 11 has a pair of left and right seat frames 11s (only one is shown) at the rear. A seat 16 on which the occupant sits is provided on the seat frame 11 s, and a storage box 17 that opens upward is provided below the seat 16. A fuel tank 18 is disposed behind the storage box 17.

  The power unit 20 includes an engine 30 as a drive source and a transmission case 40 provided behind the engine 30. The transmission case 40 incorporates a V-belt type continuously variable transmission 50 that transmits the driving force of the engine 30 to the rear wheels 15R. The power unit 20 is swingably attached to the rear end portion of the vehicle body frame 11, and the power of the engine 30 is transmitted to the rear wheel 15 </ b> R via the V-belt type continuously variable transmission 50 in the transmission case 40. Therefore, the power unit 20 also serves as a rear swing arm.

As shown mainly in FIG. 3, the engine 30 includes a crankcase 31, a cylinder block 32, a cylinder head 33, and a cylinder head cover 34. A cylinder block 32 oriented in a substantially horizontal direction is coupled to the front end of the crankcase 31, a cylinder head 33 is coupled to the front end of the cylinder block 32, and a cylinder head cover 34 is coupled to the front end of the cylinder head 33.
A crankshaft 31c is rotatably supported by ball bearings 31b and 31b held by the crankcase 31, and a piston 32p is slidably provided in the cylinder block 32. The crankshaft 31c and the piston 32p are connected by a connecting rod 32c, and the crankshaft 31c is rotated by the reciprocating motion of the piston 32p. The crankshaft 31c constitutes a primary shaft 51 described later. An intake pipe 35 (FIG. 1) and an exhaust pipe 36 (FIG. 1) communicating with the combustion chamber 33c are connected to the cylinder head 33. As shown in FIG. 2, a fuel supply device 35 a and an air cleaner 35 c are connected to the intake pipe 35. A silencer (not shown) is connected to the exhaust device 36.

  In FIG. 3, 30p is an ignition plug, 30c is provided in the cylinder head cover 34, and is a camshaft for valve drive that is rotationally driven from the crankshaft 31c via the chain c, and 31g is around the crankshaft 31c in the crankcase cover 31e. Is a generator having a stator and a rotor fixed to the crankshaft 31c.

  As shown in FIG. 3, a transmission case (also simply referred to as a case) 40 is configured as a case that forms a part of the power unit 20 described above. The case 40 has a right case 40R and a left case 40L coupled thereto. The right case 40R is manufactured integrally with the crankcase 31. A gear box cover 40C constituting a gear box (40G) for reducing the rotation of the secondary shaft 52 and transmitting it to the rear wheel shaft 55 is coupled to the rear portion of the right case 40R.

4 is a partially enlarged view of FIG. 3, and FIG. 5 is a partially omitted V arrow view of FIG.
As shown mainly in FIG. 3, the V-belt continuously variable transmission 50 is supported by a drive pulley 60 supported by a primary shaft 51 that is a first pulley shaft and a secondary shaft 52 that is a second pulley shaft. The driven pulley 70 and a V belt 53 stretched between the driving pulley 60 and the driven pulley 70 are provided. The V belt type continuously variable transmission 50 includes a case 40 that houses the drive pulley 60, the driven pulley 70, and the V belt 53, and a groove width variable mechanism 80 that changes the groove width of the drive pulley 60 (see FIG. 4), a drive unit 90 for operating the variable groove width mechanism 80, and a power transmission unit 100 for transmitting the power of the drive unit 90 to the variable groove width mechanism 80.

The variable groove width mechanism 80 (and therefore the power transmission unit 100 and the like) can be configured to change the groove width of the driven pulley 70 instead of the groove width of the drive pulley 60. It is also possible to change the groove width and the groove width of the driven pulley 70. Therefore, in the present application, “pulley shaft” means the first and / or second pulley shaft.
One of the features of the V-belt type continuously variable transmission 50 of this embodiment is that the drive unit 90 and the power transmission unit 100 are arranged in the case 40.
Hereinafter, the configuration of the V-belt type continuously variable transmission 50 will be sequentially described.

As shown in FIGS. 3 and 4, in this embodiment, the primary shaft 51 is constituted by the crankshaft 31c as described above.
The primary shaft 51 includes a large-diameter portion 51a that is supported at both ends by bearings 31b and 31b, which are bearing members, and a support portion for the movable pulley 62 in the drive pulley 60 that is provided on the large-diameter portion 51a via a step portion 51d. And a small-diameter portion 51b.

As shown in FIG. 4, in this embodiment, the drive pulley 60 is provided with a groove width variable mechanism 80.
The drive pulley 60 includes a fixed pulley (fixed half) 61 that does not move in the axial direction of the primary shaft (pulley shaft) 51, and a movable pulley (movable half) that is movable in the axial direction with respect to the primary shaft 51 and is relatively non-rotatable. Body) 62.
The groove width variable mechanism 80 changes the groove width of the pulley 60, that is, the distance between the fixed pulley 61 and the movable pulley 62 by sliding the movable pulley 62 in the axial direction along the support portion 51 b of the movable pulley 62 in the pulley shaft 51. It is a mechanism to do.
The groove width variable mechanism 80 is provided on the torque transmission part 110 that is not rotatable relative to the pulley shaft 51 and the movable pulley 62, and the boss part 63 that transmits torque between the torque transmission part 110. And have.

FIG. 6 is an exploded perspective view showing a main part of the torque transmission unit 110.
4 to 6, the movable pulley 62 includes a boss portion 63 supported by the pulley shaft 51. The boss portion 63 includes a sliding portion 63a that supports the movable pulley 62 so as to be movable in the pulley shaft direction. A torque-transmitted portion 64 to which the torque of the pulley shaft 51 is transmitted is provided so as to be spaced apart in the radial direction of the pulley shaft.
The torque transmission part 110 has a flange part 111 extending in the radial direction of the pulley shaft 51 and an axial direction part 112 provided integrally with the flange part 111 and extending in the axial direction. The axial direction portion 112 is located on the outer side in the radial direction from the surface 63a of the movable pulley 62 facing the support portion 51b of the movable pulley 62 on the pulley shaft 51 (in this embodiment, the inner peripheral surface of the boss portion 63). Yes. A plurality of the axial direction portions 112 (three in this embodiment at an equal pitch in the circumferential direction) are provided.

Although the torque transmission part 110 can be formed integrally with the primary shaft 51, in this embodiment, the torque transmission part 110 is constituted by a member separate from the pulley shaft 51 (this member is also referred to as a torque transmission member). It is.
The flange portion 111 of the torque transmitting portion 110 has a shape in which the disk-shaped portion 111a is radially extended at three locations in the radial direction, and the axial direction portion 112 is integrally formed at the tip of the extended portion. .

The boss portion 63 of the movable pulley 62 is provided with a torque transmission surface 64 through which torque is transmitted to and from the axial direction portion 112 of the torque transmission portion 110. The torque transmission surface 64 is movable relative to the axial direction portion 112 in the axial direction.
The boss portion 63 of the movable pulley 62 is provided with a hole 65 into which the axial direction portion 112 of the torque transmission portion 110 is inserted. The hole 65 has a fan-shaped cross section and corresponds to the cross section of the axial direction portion 112 and substantially coincides with it. An end surface of the hole 65 in the circumferential direction forms a torque transmission surface 64. As described above, the axial direction portion 112 is positioned outside the inner peripheral surface 63a of the boss portion 63 in the radial direction while being inserted into the hole 65 of the boss portion 63.

Between the axial direction portion 112 of the torque transmitting portion 110 and the torque transmitting surface 64 of the boss portion 63, a desired hardness is obtained by mixing a synthetic resin (for example, polyamide resin (for example, PA66) with a curing material (for example, carbon). The shock absorbing member 66 of the material) is provided.
The buffer member 66 is mounted on the inner side of the tip end portion of the axial direction portion 112 in the torque transmitting portion 110 and has a shape suitable for the tip end portion of the axial direction portion 112. The buffer member 66 shown in FIG. 6 includes a curved inner peripheral wall portion 66a, both side wall portions 66b and 66b, a bottom wall portion 66c, and a projection 66d protruding outward in the radial direction at the inner peripheral wall portion 66a. It is an integral molded product.

A hole 112 d is provided in the axial direction portion 112 of the torque transmitting portion 110.
The buffer member 66 is configured such that the protrusion 66d of the inner peripheral wall portion 66a is fitted into the hole 112d of the axial direction portion 112, and the inner peripheral wall portion 66a is joined to the inside of the tip portion of the axial direction portion 112 to thereby connect the axial direction portion 112. It is attached to the tip part of.
The axial direction part 112 is inserted in the hole 65 of the boss | hub part 63 with the buffer member 66 in the state in which the buffer member 66 was mounted | worn. In a state where the buffer member 66 is inserted into the hole 65, the outer surface 66 b 1 of the side wall portion 66 b of the buffer member 66 constitutes a torque transmission surface that contacts the torque transmission surface 64 of the boss portion 63.

  The buffer member 66 can slide in the axial direction in the hole 65 of the boss portion 63 together with the axial direction portion 112. However, since the projection 66d of the buffer member 66 and the hole 112d of the axial direction portion 112 are engaged, the axial line Even if the direction portion 112 slides, the buffer member 66 does not come off the axial direction portion 112.

  6 shows a configuration in which the buffer member 66 is mounted inside the tip end portion of the axial direction portion 112, but the buffer member 66 may be configured to be mounted outside the tip end portion of the axial direction portion 112. it can. Further, the buffer member 66 may not be mounted on the axial direction portion 112, and in this case, the side surface of the axial direction portion 112 constitutes a torque transmission surface that contacts the torque transmission surface 64 of the boss portion 63. To do.

  5 and 6, 67 is a cylindrical member. The cylindrical member 67 is inserted into the boss portion 63 of the movable pulley 62 and attached to the small diameter portion 51 b of the pulley shaft 51. As shown in FIG. 4, a double nut 68 is attached to the tip of the small diameter portion 51b, and the torque transmission member 110, the cylindrical member 67, and the fixed member are fixed between the double nut 68 and the step portion 51d of the primary shaft 51. The pulley 61 is fastened together and fixed on the small diameter part 51b. That is, the torque transmission member 110 is fixed to the pulley shaft 51 so as not to rotate relative to the flange shaft 111 by being sandwiched between the one end portion 67a of the cylindrical member 67 and the step portion 51d. The fixed pulley 61 is fixed to the pulley shaft 51 so as not to rotate relative to the pulley shaft 51 by being sandwiched between the other end 67 b of the cylindrical member 67 and the double nut 68.

As described above, the movable pulley 62 is attached to the pulley shaft 51 so as not to rotate relative to the pulley shaft 51 and to be slidable by inserting the axial direction portion 112 of the torque transmitting portion 110 into the hole 65 of the boss portion 63.
As shown in FIGS. 4 and 5, an engaging member 120 is disposed on the outer periphery of the boss portion 63 of the movable pulley 62 to slide the movable pulley 62. The engaging member 120 will be described in detail later together with the power transmission unit 100.

As shown in FIGS. 4 and 5, the drive unit 90 includes a motor unit M1 (FIG. 4) in which a motor (servo motor) M (FIG. 5) as a drive source is housed, The output shaft 91 of the drive unit 90 is provided, and the output shaft 91 is arranged in parallel with the primary shaft 51. When the groove width of the driven pulley 70 is changed by the drive unit 90, the output shaft 91 is arranged in parallel with the secondary shaft 52.
The drive unit 90 includes a reduction gear train 92 that transmits the power of the motor M to the output shaft 91. A ball screw (male screw) 93 is concentrically coupled to the gear 92e at the final stage of the reduction gear train 92. The base side of the output shaft 91 is formed in a cylindrical shape, and a ball screw (female screw) 91 b is formed on the inner surface thereof, and this female screw 91 b is screwed into the ball screw (male screw) 93. Therefore, when the ball screw 93 rotates through the reduction gear train 92 by driving the motor M, the output shaft 91 moves forward and backward in the axial direction (the directions of the arrows X1 and X2 in FIG. 4) according to the rotation direction.

  The drive unit 90 is fixed in the case 40 by fastening a gear case 94 containing the reduction gear train 92 to a mounting portion 41 (FIG. 3) provided in the case 40 with a screw 95. In this embodiment, the gear case 94 (that is, the drive unit 90) is covered with the side cover 40LC that forms a part of the left case 40L by being detachably attached to the left case 40L with the screw 42, whereby the drive unit 90 However, it is also possible to adopt a configuration in which the drive unit 90 and the power transmission unit 100 are accommodated in the case 40 by completely integrating the side cover 40LC with the left case 40L.

  As shown in FIG. 4, the distal end 91 a of the output shaft 91 protrudes toward the V belt 53 from the motor unit M <b> 1 of the drive unit 90, and at least a part of the output shaft 91 as viewed from the direction orthogonal to the output shaft 91. 91c is disposed within the belt width W of the V-belt. The motor unit M1 is disposed outside the belt width W. As shown in FIGS. 2 and 5, the output shaft 91 is disposed on a line L <b> 1 connecting the primary shaft 51 and the secondary shaft 52 in the rotation locus 53 i of the V belt 53 as viewed from the axial direction of the output shaft 91. is there. As shown in FIG. 4, the reduction gear train 92 is disposed outside the belt width W of the V belt 53, and as shown in FIG. 5, the reduction gear train 92 overlaps the V belt 53 when viewed from the axial direction of the output shaft 91. Arrange as follows.

As shown in FIGS. 4 and 5, the power transmission unit 100 is for transmitting the power of the drive unit 90 to the groove width variable mechanism 80, and includes the engaging member 120 and the connecting member 130. Yes. The engaging member 120 and the connecting member 130 are coupled by a screw 131. The connecting member 130 is coupled to the output shaft 91 with a screw 132. Therefore, when the output shaft 91 advances and retracts, the engaging member 120 and the connecting member 130 also advance and retract together.
As shown in FIG. 4, the connecting portion 133 of the connecting member 130 with the output shaft 91 is connected to the tip surface 91 e of the output shaft 91.

  As shown in FIG. 5, the engaging member 120 has an engaging portion 121 that indirectly engages with the boss portion 63 of the movable pulley 62 to slide the movable pulley 62. As shown in FIG. 4, a bearing 69 is fixed to the outer periphery of the boss portion 63 of the movable pulley 62 so as not to slide in the axial direction of the boss portion 63. Similarly, an engagement ring 122 is fixed to the outer periphery of the bearing 69 so as not to slide in the axial direction. A ring-shaped engagement groove 123 is provided on the outer periphery of the engagement ring 122, and the engagement portion 121 of the engagement member 120 is engaged with the engagement groove 123. Thus, in the illustrated example, the engaging portion 121 of the engaging member 120 is indirectly engaged with the boss portion 63 of the movable pulley 62 (via the engaging ring 122 and the bearing 69). It is also possible to directly engage the joint portion 121 with the boss portion 63.

  As shown in FIG. 4, the engaging portion 121 is connected to the bearing portion 31b between the movable pulley 62 and the bearing portion 31b that supports the pulley shaft 51 to which the movable pulley 62 is attached in the axial direction of the movable pulley 62. Adjacent to each other. That is, the engaging part 121 is arranged as close as possible to the bearing part 31b. The engaging portion 121 is preferably engaged with the boss portion 63 of the movable pulley 62 at at least two positions facing each other across the pulley shaft 51. In this embodiment, the engaging portion 121 is related to the pulley shaft 51 ( In other words, they are engaged at two points symmetrically with respect to the rotation center of the boss portion 63.

As shown in FIG. 3, the secondary shaft 52 that is the driven shaft of the V-belt type continuously variable transmission 50 is rotatably supported by the left case 40L of the case 40 and the gear box cover 40C. A driven pulley 70 is provided on the secondary shaft 52 via a centrifugal clutch 54.
The driven pulley 70 includes a fixed pulley (fixed half) 71 and a movable pulley (movable half) 72. An endless V-belt 53 is stretched between the driving pulley 60 and the driven pulley 70, and the rotation of the driving pulley 60 is transmitted to the driven pulley 70. When the rotational speed of the driven pulley 70 exceeds the predetermined rotational speed, the centrifugal clutch 54 provided between the driven pulley 70 and the secondary shaft 52 is connected, and the secondary shaft 52 starts to rotate.

A gear train (gear box) 40G that decelerates the rotation of the secondary shaft 52 and transmits it to the rear wheel shaft 55 includes a gear 52g provided on the secondary shaft 52, a large-diameter gear 141 that meshes with the gear 52g, and the large gear. A small gear 142 having a smaller diameter than 141 and rotating with the large gear 141 and a large gear 143 meshing with the small gear 142 are provided. The large gear 143 is attached to the rear wheel shaft 55 so as not to be relatively rotatable.
Therefore, the rotation of the secondary shaft 52 is decelerated and transmitted to the rear wheel shaft 55, and the rear wheel 15R (FIG. 1) attached to the rear wheel shaft 55 is driven.

  The movable pulley 72 in the driven pulley 70 is attached to the secondary shaft 52 so as to be movable in the axial direction. The movable pulley 72 is urged in a direction approaching the fixed pulley 71 by a coil spring 73, and moves in the axial direction according to the tension acting on the V belt 53. That is, when the movable pulley 62 of the driving pulley 60 is displaced in the direction of narrowing the groove width and the winding diameter of the V belt 53 around the driving pulley 60 increases, the V belt wound around the driven pulley 70 correspondingly. 53 is pulled toward the drive pulley 60 and the tension acting on the V-belt 53 is increased. With this increase in tension, the movable pulley 72 of the driven pulley 70 is displaced in the direction of increasing the groove width, and the V-belt to the driven pulley 70 is increased. The winding diameter of 53 becomes small and the secondary shaft 52 rotates at high speed. When the movable pulley 62 of the driving pulley 60 is displaced in the direction of widening the groove width, the operation is reversed, and the secondary shaft 52 rotates at a low speed.

  When the drive unit 90 operates under the control of a control unit (not shown) and the output shaft 91 protrudes in the direction of the arrow X1 in FIG. 4 and the movable pulley 62 slides in the X1 direction, the distance between the fixed pulley 61 and the movable pulley 62 increases. As a result, the winding diameter of the V belt 53 around the driving pulley 60 decreases and the winding diameter of the V belt 53 around the driven pulley 70 increases, so that the rear wheel 15R is driven to rotate at a low speed so that it can withstand high loads. The Rukoto. Conversely, when the output shaft 91 slides in the direction of the arrow X2 and the movable pulley 62 slides in the X2 direction, the distance between the fixed pulley 61 and the movable pulley 62 becomes narrow, and the winding diameter of the V belt 53 around the drive pulley 60 is reduced. Becomes larger and the winding diameter of the V-belt 53 around the driven pulley 70 becomes smaller, and the rear wheel 15R is rotationally driven at a high speed.

According to the V-belt type continuously variable transmission 50 as described above, the following operational effects can be obtained.
(A) The movable pulley 62 includes a boss portion 63 supported by the pulley shaft 51. The boss portion 63 transmits the torque of the pulley shaft 51 to the sliding portion 63a that supports the movable pulley 62 so as to be movable in the pulley shaft direction. Since the to-be-torque transmitted portion 64 is spaced apart in the radial direction of the pulley shaft, the sliding of the pulley shaft direction and the to-be-torque-transmitted force are separated from each other in the radial direction. It is possible to improve the sliding and torque transmission of the movable pulley by reducing the stress concentration while avoiding the increase in the size.
That is, when transmitting torque of the same magnitude, the surface pressure acting on the torque transmission surface can be reduced as compared with the conventional case. The reduction of the surface pressure can contribute to the miniaturization of the torque transmission part and, consequently, the miniaturization of the entire V-belt continuously variable transmission.
(B) By providing the torque transmission surface 64 separately from the sliding surface 63a, the load applied to the sliding surface 63a is reduced while the sliding surface 63a and the torque transmission surface 64 are formed on the same member 62. Can do. Therefore, it is not necessary to supply oil or grease to the sliding surface 63a.
(C) The torque transmission part (torque transmission surface 64) of the boss part 63 transmits the torque of the pulley shaft to the movable pulley 62 by engaging with the torque transmission part 110 provided so as not to rotate relative to the pulley shaft. The torque transmitting part 110 and the torque transmitting part 64 are relatively movable along the axial direction of the pulley shaft, and transmit torque by abutting in the rotational direction of the pulley shaft. Accordingly, the torque of the pulley shaft can be transmitted even when the torque transmission unit 110 and the torque receiving unit move relative to each other.
(D) A torque transmitting portion 110 provided so as not to rotate relative to the pulley shaft 51 is provided integrally with the flange portion 111 extending in the radial direction of the pulley shaft 51 and the movable pulley 62. The pulley shaft 51 has an axial direction portion 112 that is located on the outer side in the radial direction from the surface 63a facing the support portion 51b of the movable pulley 62 and extends in the axial direction of the pulley shaft 51. Since the torque is transmitted between the boss portion 63 and the torque transmission surface 64, the surface pressure acting on the torque transmission surface 64 can be reduced as compared with the prior art.
That is, when transmitting torque of the same magnitude, the surface pressure acting on the torque transmission surface 64 can be reduced compared to the conventional case. The reduction of the surface pressure can contribute to the downsizing of the torque transmission unit 110 and the downsizing of the V-belt continuously variable transmission 50 as a whole.
(E) The pulley shaft 51 includes a large-diameter portion 51a and a small-diameter portion 51d provided on the large-diameter portion 51a via a step portion 51d and constituting a support portion for the movable pulley 62. 110 is a member separate from the pulley shaft 51, and the flange portion 111 of the member 110 is inserted into the boss portion 63 of the movable pulley 62 and attached to the small diameter portion 51 d of the pulley shaft 51. By being sandwiched between the end portion 67a and the stepped portion 51d, it is fixed so as not to rotate relative to the pulley shaft 51. Therefore, it is easier than the case where the torque transmitting portion 110 is formed integrally with the pulley shaft 51. The torque transmission unit 110 can be reliably fixed to the pulley shaft 51 so as not to be relatively rotatable.
(F) Since the buffer member 66 made of synthetic resin is provided between the axial direction portion 112 of the torque transmission portion 110 and the torque transmission surface 64 of the boss portion 63, it is not necessary to supply grease to the torque transmission surface 64. In addition, the generation of noise can be suppressed.
(G) Since a plurality of the axial direction portions 112 of the torque transmission unit 110 are provided around the axis, torque transmission can be performed more smoothly and the surface pressure can be more reliably reduced.
(H) Since the engaging member 120 is arranged on the outer periphery of the boss portion 63 of the movable pulley 62 via the bearing 69 for sliding the movable pulley 62, the power transmission system for sliding the movable pulley 62 can be made compact. It can be configured. Further, wear of the anchor member 120 can be prevented by shortening the axial length and preventing the torque from being transmitted to the engaging member 120.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and can be appropriately modified within the scope of the gist of the present invention.

  31b Bearing part, 40 Transmission case, 50 V belt type continuously variable transmission, 51 Primary shaft, 51a Large diameter part, 51b Support part (small diameter part), 51d Step part, 52 Secondary shaft, 53 V belt, 60 Drive pulley , 62 Movable pulley, 63 Boss part, 63a Opposing surface, 64 Torque transmission surface, 66 Buffer member, 67 Cylindrical member, 70 Driven pulley, 80 Groove width variable mechanism, 90 Drive unit, 91 Output shaft, 91a Tip surface, 92 Deceleration Gear train, 100 power transmission unit, 110 torque transmission unit, 111 flange unit, 112 axial direction unit, 120 engagement member, 121 engagement unit, 130 coupling member, 133 coupling unit.

Claims (6)

A driving pulley supported by a primary shaft that is a first pulley shaft, a driven pulley supported by a secondary shaft that is a second pulley shaft, and a V-belt stretched between the driving pulley and the driven pulley And a groove width variable mechanism for changing the groove width of the pulley by sliding the movable pulley in the driving pulley and / or the driven pulley in the axial direction along the support portion of the movable pulley in the pulley shaft. A continuously variable transmission,
The movable pulley includes a boss portion supported by the pulley shaft;
The boss portion is provided with a sliding portion that supports the movable pulley so as to be movable in the pulley shaft direction, and a torque-transmitted portion that transmits the torque of the pulley shaft, spaced apart in the radial direction of the pulley shaft. A V-belt type continuously variable transmission. A torque transmitting portion of the boss portion is engaged with a torque transmitting portion provided so as not to rotate relative to the pulley shaft, thereby transmitting the torque of the pulley shaft to the movable pulley;
2. The torque transmitting unit and the torque-transmitting unit are configured to move relative to each other along an axial direction of the pulley shaft, and transmit torque by abutting in the rotational direction of the pulley shaft. The described V-belt type continuously variable transmission. The pulley shaft has a large-diameter portion, and a small-diameter portion that is provided on the large-diameter portion via a step portion and constitutes a support portion of the movable pulley,
The torque transmission portion is a member separate from the pulley shaft, and has a flange portion extending in a radial direction of the pulley shaft and the axial portion integrally provided on the flange portion. The flange portion is inserted between the boss portion of the movable pulley and sandwiched between the end portion of the cylindrical member attached to the small diameter portion of the pulley shaft and the stepped portion, so that the relative rotation with respect to the pulley shaft is impossible. The V-belt type continuously variable transmission according to claim 2, wherein the V-belt type continuously variable transmission is fixed to the belt.   The V-belt type continuously variable transmission according to claim 3, wherein a buffer member made of synthetic resin is provided between an axial direction portion of the torque transmission portion and a torque transmission surface of the boss portion.   5. The V-belt continuously variable transmission according to claim 2, wherein a plurality of engaging portions of the torque transmitting portion are provided around an axis.   6. The V-belt type non-removable member according to claim 1, wherein an engaging member is arranged on the outer periphery of the boss portion of the movable pulley via a bearing for sliding the movable pulley. Step transmission.

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