JP2015113934A - Torque cam device - Google Patents

Abstract

There is provided a torque cam device capable of increasing a thrust generated according to a transmitted torque and suppressing a decrease in a position where a pressing member and a pressed member are in contact with each other. A first cam surface having a concave portion and a convex portion, and a second cam having a concave portion or a convex portion formed so as to be shifted in a circumferential direction and a radial direction from the concave portion or the convex portion on the first cam surface. And a first cam follower 25 and a second cam surface 35 that contact the first cam surface 29 and transmit the torque when torque is transmitted to either the pressing member or the pressed member. And a second cam follower 26 for transmitting torque. [Selection] Figure 1

Description

  The present invention relates to a torque cam device that generates axial thrust according to transmitted torque, and more particularly to a torque cam device configured such that a pressing member and a pressed member can move relatively in the axial direction. Is.

  Patent Documents 1 to 3 describe a torque cam device configured to generate a clamping pressure for clamping a belt in accordance with torque transmitted to a belt type continuously variable transmission. The torque cam device described in each patent document includes a cylindrical drive-side cam integrally connected to a secondary pulley provided in the belt-type continuously variable transmission, and torque transmitted to the belt-type continuously variable transmission. In addition, it is arranged to face the cam surface formed on the drive side cam so as to contact the drive side cam to transmit torque and apply a clamping pressure to clamp the belt according to the transmitted torque. It is comprised by the drive side cam.

  In addition, the torque cam device described in Patent Document 2 includes a first torque cam device that generates a pinching force for pinching the belt when transmitting torque so that the vehicle moves forward, and a vehicle that moves backward or forward travels. And a second torque cam device for generating a clamping pressure for clamping the belt when torque is transmitted so as to decelerate sometimes. A driving cam and a driven cam constituting the second torque cam device are provided on the inner peripheral side of the driving cam and the driven cam constituting the first torque cam device.

JP 2011-080560 A JP 2008-051177 A Japanese Patent Laid-Open No. 08-233049

  By the way, the torque cam apparatus described in Patent Document 1 is configured so that a pressing member having two irregularities in the circumferential direction and a pressed member are arranged to face each other. Therefore, when the torque cam device generates thrust while transmitting torque, the contact position between the pressing member and the pressed member is two places in the circumferential direction, so the load in the circumferential direction that presses the pressed member is reduced. The balance may be lost. Moreover, as described in Patent Document 3, by forming a plurality of irregularities in the circumferential direction, it is possible to suppress the balance of the load in the circumferential direction that presses the pressed member from being lost. However, when many irregularities are formed in the circumferential direction, the amount of change in the height of the convex portion or the amount of change in the depth of the concave portion per unit length in the circumferential direction becomes small. Therefore, there is a possibility that the thrust generated according to the transmitted torque becomes small.

  The present invention has been made paying attention to the technical problem described above, and can increase the thrust generated according to the transmitted torque and reduce the number of places where the pressing member and the pressed member are in contact with each other. An object of the present invention is to provide a torque cam device that can suppress this.

  In order to achieve the above object, the invention according to claim 1 is directed to either one of a pressing member and a pressed member that can rotate relative to each other, and a cam surface having a tip end surface in the axial direction curved in an uneven shape in the axial direction. A cylindrical cam member is attached, and a cam follower that is abutted against the cam surface and is moved in the axial direction along the uneven shape of the cam surface is either the pressing member or the pressed member. In the torque cam device attached to the first cam surface, the cam surface includes a first cam surface having the concave portion and a convex portion, and a concave portion formed by shifting the concave portion or the convex portion in the first cam surface in a circumferential direction and a radial direction. Or at least a second cam surface having a convex portion, and the cam follower contacts the first cam surface when torque is transmitted to either the pressing member or the pressed member. And it is characterized in that it comprises a second cam follower for transmitting torque in contact with the second cam surface and the first cam follower for transmitting torque.

  According to a second aspect of the invention, in the first aspect of the invention, when torque is transmitted to the pressing member, the first cam surface and the first cam follower come into contact with each other so that the pressed member moves in the axial direction. While being pressed, the second cam surface and the second cam follower come into contact with each other in the same direction as the load direction in which the pressed member is pressed in the axial direction to press the pressed member in the axial direction. A torque cam device configured as described above.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the first cam surface has two concave portions or convex portions formed at a distance from each other in the circumferential direction, and the first cam surface The follower has two cam followers that respectively contact the two concave portions or convex portions of the first cam surface and transmit torque, and the second cam surface is formed at a distance from each other in the circumferential direction. And the second cam follower has two cam followers that contact the two recesses or projections on the second cam surface to transmit torque. Torque cam device.

  According to the present invention, when torque is transmitted to either the pressing member or the pressed member, the first cam follower that contacts the first cam surface and transmits the torque is contacted to the second cam surface. And a second cam follower for transmitting torque. Moreover, the recessed part or convex part formed in the 1st cam surface and the recessed part or convex part formed in the 2nd cam surface are shifted | deviated and formed in the circumferential direction and radial direction. Therefore, when the first cam follower contacts the first cam surface and transmits torque to generate thrust, the second cam follower contacts the second cam surface and transmits torque to generate thrust. Let As a result, the position where the thrust is applied to the pressing member or the pressed member can be increased, so that it is possible to suppress the balance of the load in the circumferential direction pressing the pressed member from being lost. Further, since the number of irregularities formed on each cam surface can be reduced, the amount of change in the height of the irregularities formed on each cam surface per unit length in the circumferential direction can be reduced. it can. Therefore, the thrust generated according to the torque transmitted to the torque cam device can be increased.

  The first cam surface and the second cam surface each have two concave portions or convex portions that are spaced apart from each other in the circumferential direction, and the first cam follower and the second cam follower are respectively the first cam follower and the first cam follower. In the case of having two cam followers that contact the concave portions or the convex portions on the cam surface and the second cam surface and transmit torque, there are four contact portions between the pressing member and the pressed member in the circumferential direction. Therefore, the posture of the pressed member can be stabilized. Also, the amount of change in the height of the unevenness formed on the cam surface per unit length in the circumferential direction is greater than when three or more recesses or protrusions are formed on the first cam surface and the second cam surface, respectively. The thrust generated according to the transmitted torque can be increased.

It is sectional drawing for demonstrating an example of a structure of the torque cam apparatus which concerns on this invention. It is a perspective view for demonstrating the structure of a to-be-pressed member. It is a perspective view for demonstrating the structure of a press member. It is a figure which shows the state which the 1st cam follower and the 1st cam surface are contacting. It is a figure which shows the state which the 2nd cam follower and the 2nd cam surface are contacting. It is a schematic diagram for demonstrating the structure of a belt-type continuously variable transmission.

  An example of a torque cam device according to the present invention will be described with reference to an example mounted on a belt type continuously variable transmission. First, the configuration of the belt type continuously variable transmission will be briefly described. FIG. 6 is a schematic diagram of a power transmission device mounted on a vehicle. In the power transmission device shown in FIG. 6, a transmission device 3 configured in the same manner as a conventionally known torque converter, forward / reverse switching mechanism or the like is connected to an output shaft 2 of a power source 1 such as an engine or a motor. . The belt-type continuously variable transmission 5 is connected to the output shaft 4 of the transmission device 3, and the output shaft 6 of the belt-type continuously variable transmission 5 arranged in parallel with the output shaft 4 is connected to a not-shown gear train or differential gear. The drive wheels 7 are connected. In addition, since the output shaft 4 of the transmission device 3 functions as an input shaft of the belt type continuously variable transmission 5, it may be referred to as the input shaft 4 in the following description.

  A belt-type continuously variable transmission 5 shown in FIG. 6 is a dry-type belt-type continuously variable transmission in which a pulley and a belt contact each other without passing through lubricating oil to transmit torque, and is connected to an input shaft 4. A primary pulley 8, a secondary pulley 9 connected to the output shaft 6, and a belt 10 that is wound around the pulleys 8 and 9 and transmits torque are provided. The primary pulley 8 can be configured in the same manner as a conventionally known primary pulley, and moves along a fixed sheave 11 integrated with the input shaft 4 and the central axis of the input shaft 4. And a movable sheave 12 configured to rotate integrally with the input shaft 4. Each of the sheaves 11 and 12 is formed in a tapered shape, and a belt 10 covered with a resin or the like is wound around a V groove formed by the tapered surfaces. The primary pulley 8 is configured to change the winding radius of the belt 10 and is provided with a thrust applying device 13 such as a hydraulic actuator or an electromagnetic actuator that moves the movable sheave 12 in the axial direction.

  The secondary pulley 9 is restricted from moving in the axial direction and can move along the fixed sheave 14 that is formed so as to rotate integrally with the output shaft 6 during torque transmission, and the central axis of the output shaft 6. In addition, a movable sheave 15 configured to rotate integrally with the output shaft 6 during torque transmission is provided. Each of the sheaves 14 and 15 is formed in a tapered shape, and the belt 10 is wound around a V groove formed by the tapered surfaces. The secondary pulley 9 is configured to change the transmission torque capacity of the belt-type continuously variable transmission 5 by generating a clamping pressure that clamps the belt 10, and fixes the movable sheave 15 in the axial direction. A pressing device 16 that presses toward the sheave 14 is provided.

  Therefore, in the example shown in FIG. 6, the gear ratio of the belt-type continuously variable transmission 5 is changed by controlling the thrust applying device 13 to change the width of the V groove, and the belt 10 is clamped by the pressing device 16. It is comprised so that a pinching pressure may be produced. In addition, it is preferable that the clamping pressure which clamps the belt 10 changes according to the torque which the belt-type continuously variable transmission 5 transmits.

  FIG. 1 shows a cross-sectional view for explaining an example of the configuration of the secondary pulley 9 and the pressing device 16. 1 above the central axis shown in FIG. 1 is when the transmission ratio of the belt-type continuously variable transmission 5 is maximum, that is, the movable sheave 15 is farthest from the fixed sheave 14 and the winding radius of the belt 10 is minimized. The lower side shows the state when the belt-type continuously variable transmission 5 has the minimum gear ratio, that is, the movable sheave 15 is closest to the fixed sheave 14 side, and the winding radius of the belt 10 is maximized. It shows the state when

  A movable sheave 15 shown in FIG. 1 includes a tapered portion 15b having a tapered surface 15a formed on one side surface in the axial direction, and a cylindrical boss portion 15c formed to protrude in the axial direction from the back side of the tapered portion 15b. have. The boss portion 15c is engaged with the holding shaft 17 via an engaging member 18 such as a key or a spline so as to rotate integrally with the holding shaft 17 with which the fixed sheave 14 is integrally formed. In other words, the boss portion 15 c and the holding shaft 17 are configured to rotate integrally, and the movable sheave 15 can relatively move along the axial direction of the holding shaft 17. In the example shown in FIG. 1, bushes 19 and 20 made of a resin material are provided on both sides of a portion where the engaging member 18 is connected to the boss portion 15 c in the axial direction, and the movable sheave 15 is provided. Is configured to reduce sliding frictional resistance when moving in the axial direction. The bushes 19 and 20 are connected to the inner peripheral surfaces of the tapered portion 15b and the boss portion 15c by press-fitting or the like so as to move integrally with the tapered portion 15b and the boss portion 15c.

  A pressing device 16 configured to press the movable sheave 15 configured as described above toward the fixed sheave 14 and apply a clamping pressure to clamp the belt 10 is provided on the back side of the tapered portion 15b. . Specifically, when torque is transmitted, a torque cam mechanism 21 that applies a thrust according to the transmitted torque to the movable sheave 15 and an elastic force that presses the movable sheave 15 toward the fixed sheave 14 side. The pressing device 16 is constituted by the coil spring 22 to be moved.

  The torque cam mechanism 21 is rotatably held by a case (not shown) and the like, and the movement in the axial direction is restricted. The torque cam mechanism 21 contacts the pressing member 23 according to the transmitted torque and transmits torque. It is comprised by the to-be-pressed member 24 which receives the thrust from the pressing member 23 to the fixed sheave 14 side according to the transmitted torque.

  A perspective view for explaining the configuration of the pressed member 24 is shown in FIG. The pressed member 24 shown in FIG. 2 includes two first cam followers 25 and 25 formed on the inner peripheral side in the radial direction, and two second cam followers 26 and 26 formed on the outer peripheral side. Yes. The positions where the first cam follower 25 and the second cam follower 26 are provided are formed so as to be shifted in the circumferential direction. In the example shown in FIG. 2, two first cam followers 25 and two second cam followers 26 are formed and are shifted by approximately 90 degrees in the circumferential direction. The number by which 25 (26) is formed and the amount or angle by which each cam follower 25 (26) is shifted in the circumferential direction are not limited to this.

  Here, the configuration of the pressed member 24 shown in FIG. 2 will be specifically described. In the example shown in FIG. 2, the outer diameter of the portion of the boss portion 15c that is connected to the tapered portion 15b is larger than the outer diameter of the end portion side of the boss portion 15c. A first cam follower 25 is formed so as to protrude in the axial direction from a large-diameter portion 15 d formed with a relatively large outer diameter. More specifically, one end portion of the first cam follower 25 is integrated with the large diameter portion 15d, and the first cam follower 25 is formed integrally with the outer peripheral surface of the boss portion 15c. Moreover, the front-end | tip part of the 1st cam follower 25 is formed in hook shape. That is, the first inclined surface 27 and the second inclined surface 28 are formed at the distal end portion of the first cam follower 25 so that the central portion in the width direction of the first cam follower 25 protrudes toward the distal end side. Note that the dry belt-type continuously variable transmission 5 is configured to prevent oil from flowing into a portion around which the belt 10 is wound. Accordingly, there may be a case where oil is not supplied to a place where the first cam follower 25 is formed. Therefore, in order to suppress metal contact between the first cam follower 25 and a first cam surface 29 described later, cam tips 30 and 31 formed of a resin material or the like are integrally formed on the inclined surfaces 27 and 28, respectively. Is formed.

  The second cam follower 26 is provided so as to rotate integrally with the first cam follower. Specifically, a second cam follower 26 is formed protruding in the axial direction from the first cylindrical portion 32 engaged by a spline so as to rotate integrally with the large diameter portion 15d. Similarly to the first cam follower 25, the second cam follower 26 is formed in a bowl shape, and a third inclined surface 33 and a fourth inclined surface 34 are formed at the tip thereof. Further, in order to suppress metal contact between the second cam follower 26 and a second cam surface 35 described later, cam tips 36 and 37 formed of a resin material or the like are integrally formed on the inclined surfaces 33 and 34, respectively. Is formed. In addition, although the position in the axial direction of the front-end | tip part of the 1st cam follower 25 and the 2nd cam follower 26 is formed so that it may correspond in the example shown in FIG. 2, the position in an axial direction differs. Also good.

  Next, the configuration of the pressing member 23 will be specifically described. A perspective view for explaining the configuration of the pressing member 23 is shown in FIG. The pressing member 23 shown in FIG. 3 is a cylindrical first cylinder having a first cam surface 29 that is formed to have substantially the same outer diameter as that of the large-diameter portion 15d and whose tip surface is curved in an uneven shape in the axial direction. A cam 38 and a second cam surface 35 that surrounds the outer peripheral surface of the first cylindrical cam 38 and is formed to have substantially the same outer diameter as that of the first cylindrical portion 32 and the tip end surface of which is curved unevenly in the axial direction. And a cylindrical second cylindrical cam 39. The pressing member 23 is provided so as to be rotatable relative to the pressed member 24. The first cylindrical cam 38 is formed integrally with an annular plate portion 40 having an outer diameter substantially the same as the tapered portion 15b, and the second cam surface 35 is formed on the second cylindrical cam 39. The end surface opposite to the end surface is configured to be restricted from moving in contact with the plate portion 40.

  The first cam surface 29 is configured to always come in contact with either the first inclined surface 27 or the second inclined surface 28 when the movable sheave 15 moves in the axial direction. Therefore, the height of the unevenness on which the first cam surface 29 is formed is greater than the amount by which the movable sheave 15 moves in the axial direction. The first cam surface 29 is configured to come into contact with either the first inclined surface 27 or the second inclined surface 28 when torque is transmitted. For this reason, when two first cam followers 25 are formed, two irregularities are formed in the circumferential direction. In other words, two first contact surfaces 41 formed over the concave and convex portions and opposed to the first inclined surface 27 are formed, formed over the concave and convex portions and opposed to the second inclined surface 28. Two second contact surfaces 42 are formed in the circumferential direction.

  FIG. 4 shows a diagram for more specifically explaining the configuration of the first cam follower 25 and the first cam surface 29. In FIG. 4, the circumferential length of the large diameter portion 15d and the first cylindrical cam 38 is shown on the horizontal axis, and the length in the axial direction is shown on the vertical axis. As shown in FIG. 4, the first cam surface 29 is configured such that the length in the axial direction changes with a predetermined amount of change with respect to the length in the circumferential direction. The first cam surface 29 contacts the first contact surface 41 that contacts the cam tip 30 attached to the first inclined surface 27 of the first cam follower 25 and the cam tip 31 attached to the second inclined surface 28. A second contact surface 42 is formed. The inclination angles of the contact surfaces 41 and 42 with respect to the circumferential direction are the same. Therefore, when the first cylindrical cam 38 and the first cam follower 25 rotate relative to each other, the first cam follower 25 has an axis along one of the first contact surface 41 and the second contact surface 42. Configured to move in the direction. When the first cam follower 25 and the first cylindrical cam 38 transmit torque, thrust according to the transmitted torque and the inclination angles of the contact surfaces 41 and 42 acts on the first cam follower 25. It is configured as follows. In the example shown in FIG. 4, the end portions of the cam chips 30 and 31 are provided so as to slightly protrude from the inclined surfaces 27 and 28. Further, the contact surfaces 41 and 42 are not limited to those formed to be inclined at a predetermined inclination angle as shown in FIG. 4, and may be formed to be curved to a predetermined curvature radius.

  On the other hand, the second cylindrical cam 39 is engaged with the outer peripheral surface of the first cylindrical cam 38 by a spline so as to rotate integrally with the first cylindrical cam 38. The second cam surface 35 formed on the second cylindrical cam 39 always contacts one of the third inclined surface 33 and the fourth inclined surface 34 when the movable sheave 15 moves in the axial direction. It is configured as follows. Therefore, the height of the unevenness on which the second cam surface 35 is formed is greater than the amount by which the movable sheave 15 moves in the axial direction. The second cam surface 35 is configured to come into contact with either the third inclined surface 33 or the fourth inclined surface 34 when torque is transmitted. Therefore, when two second cam followers 26 are formed, two irregularities are formed in the circumferential direction. In other words, two first contact surfaces 43 that are formed over the concave and convex portions and are opposed to the third inclined surface 33 are formed, are formed over the concave and convex portions and are opposed to the fourth inclined surface 34. Two fourth contact surfaces 44 are formed in the circumferential direction.

  FIG. 5 shows a diagram for more specifically explaining the configuration of the second cam follower 26 and the second cam surface 35. In FIG. 5, the circumferential length of the cylindrical portion 32 and the second cylindrical cam 39 is shown on the horizontal axis, and the length in the axial direction is shown on the vertical axis. As shown in FIG. 5, the second cam surface 35 is configured such that the length in the axial direction changes with a predetermined amount of change with respect to the length in the circumferential direction. Further, the second cam surface 35 contacts a third contact surface 43 that contacts the cam tip 36 attached to the third inclined surface 33 in the second cam follower 26 and a cam tip 37 attached to the fourth inclined surface 34. A fourth contact surface 44 is formed. The inclination angles of the contact surfaces 43 and 44 with respect to the circumferential direction are the same. Therefore, when the second cylindrical cam 39 and the second cam follower 26 are relatively rotated, the second cam follower 26 has an axial line along one of the third contact surface 43 and the fourth contact surface 44. Configured to move in the direction. When the second cam follower 26 and the second cylindrical cam 39 transmit torque, thrust according to the transmitted torque and the inclination angles of the contact surfaces 43 and 44 acts on the second cam follower 26. It is configured as follows. In the example shown in FIG. 5, the end portions of the cam tips 36 and 37 are provided so as to slightly protrude from the inclined surfaces 33 and 34. Further, the contact surfaces 43 and 44 are not limited to those formed with a predetermined inclination angle as shown in FIG. 5, but may be formed with a predetermined radius of curvature.

  The amount of circumferential displacement between the convex portion or concave portion of the first cam surface 29 and the convex portion or concave portion of the second cam surface 35, and the circumferential displacement of the first cam follower 25 and the second cam follower 26. The amount is configured to match. In other words, in the circumferential direction between the position where the first cam follower 25 is abutted against and abutted against the first cam surface 29 and the position where the second cam follower 26 is abutted against and abutted against the second cam surface 35. The amount of deviation is configured to match the amount of deviation in the circumferential direction between the concave portion or convex portion of the first cam surface 29 and the concave portion or convex portion of the second cam surface 35. That is, the phase difference between the first cam surface 29 and the second cam surface 35 and the phase difference between the first cam follower 25 and the second cam follower 26 are configured to coincide with each other. When the first cam follower 25 transmits torque to the first cam surface 29 and generates a thrust force that presses the movable sheave 15 toward the fixed sheave 14, the second cam follower 26 is moved to the second cam surface 35. Torque is transmitted to the movable sheave 15 and a thrust force that presses the movable sheave 15 toward the fixed sheave 14 is generated.

  The plate portion 40 is configured to function as a seating surface for the second cylindrical cam 39 and the coil spring 22. Specifically, the outer diameter of the second cylindrical cam 39 is larger than that of the second cylindrical cam 39, and the plate portion receives a load that the second cylindrical cam 39 is pressed in the axial direction according to the torque transmitted from the second cam follower 26. It is configured to receive on the side surfaces of 40 and to receive the elastic force of the coil spring 22. And the cylindrical output shaft 6 which protruded from the inner peripheral part of the plate part 40 to the back side is integrally formed. A gear (not shown) is connected to the outer peripheral surface of the end portion of the output shaft 6 by a spline so that torque is transmitted to the drive wheels 7 through the gear.

  In the example shown in FIG. 1, the end of the holding shaft 17 and the output shaft 6 are rotatably held in a case (not shown) via radial bearings 45 and 46 in which oil is sealed. A seal member 47 is provided between the plate portion 40 and the holding shaft 17. Therefore, the example shown in FIG. 1 is configured such that oil does not flow into the space surrounded by the radial bearings 45 and 46 and the seal member 47.

  Next, the operation of the torque cam mechanism 21 shown in FIG. 1 will be described. In the example shown in FIG. 1, torque is transmitted from the belt 10 to the fixed sheave 14 and the movable sheave 15 when driving force is output from the engine 1 during forward travel. That is, the torque transmitted by the belt 10 is divided into two and transmitted to the fixed sheave 14 and the movable sheave 15. The torque transmitted to the fixed sheave 14 as such is added to the torque transmitted to the boss portion 15 c via the engaging member 18 and transmitted to the movable sheave 15. Accordingly, almost all of the torque transmitted by the belt 10 is transmitted to the movable sheave 15. As the torque is transmitted to the movable sheave 15, the first cam follower 25 and the first cam surface 29 come into contact with each other, and the second cam follower 26 and the second cam surface 35 come into contact with each other. When torque is transmitted in such a state that the cam followers 25 and 26 and the cam surfaces 29 and 35 are in contact with each other, a thrust corresponding to the torque acting on the contact surface and the inclination angle of the cam surface is applied to the movable sheave 15. Works. As a result, the movable sheave 15 is pressed toward the fixed sheave 14, so that a clamping pressure for clamping the belt 10 is generated. Since the coil spring 22 is provided, the elastic force of the coil spring 22 acts on the movable sheave 15 in addition to the thrust based on the torque acting on the contact surface.

  On the other hand, torque is transmitted to the first cylindrical cam 38 and the second cylindrical cam 39 by the torque acting on the cam surfaces 29 and 35. Further, since the second cylindrical cam 39 is engaged with the first cylindrical cam 38 by splines as described above, the torque transmitted to the second cylindrical cam 38 is transmitted to the first cylindrical cam 39. Is added up. Then, the torque transmitted to the first cylindrical cam 38 is output from the belt type continuously variable transmission 5 via a gear (not shown). Note that when torque is transmitted from the drive wheels 8 such as when driving force is output from the engine 1 during reverse travel or when engine braking force is applied, the direction of the torque input to the torque cam device 21 is as described above. On the contrary, even when torque is input to the torque cam device 21 as described above, the movable sheave 15 is pressed toward the fixed sheave 14 according to the torque input to the torque cam device 21.

  When driving force is output from the engine 1 during forward travel, either the first contact surface 41 or the second contact surface 42 is in contact with the first cam follower 25 and the third contact surface 43 is Any one of the fourth contact surfaces 44 contacts the second cam follower 26. Further, when driving force is output from the engine 1 during reverse travel, or when torque is transmitted from the drive wheels 8 such as applying an engine braking force, either the first contact surface 41 or the second contact surface 42 is used. One of the third contact surface 43 and the fourth contact surface 44 contacts the second cam follower 26 while the other contacts the first cam follower 25.

  As shown in FIG. 1, the first cam surface 29 and the second cam surface 35 are formed so as to be shifted in the circumferential direction, and the first cam follower 25 and the second cam follower corresponding to the respective cam surfaces 29, 35. 26, when the movable sheave 15 is pressed toward the fixed sheave 14 in accordance with the transmitted torque, the cam followers 25, 26 are formed on the cam surfaces 29, 35 at a plurality of locations in the circumferential direction. It is hit. Therefore, it can suppress that the thrust which presses the movable sheave 15 becomes non-uniform | heterogenous in the circumferential direction. In other words, even if the number of irregularities formed on each of the cam surfaces 29 and 35 is reduced by forming a plurality of cam surfaces 29 and 35, the thrust force that presses the movable sheave 15 is not improved in the circumferential direction. It can suppress becoming uniform. As a result, the inclination angle of the inclined surface formed on each of the cam surfaces 29 and 35 can be reduced, so that the thrust acting on the movable sheave 15 can be increased in accordance with the transmitted torque.

  In particular, the first cam follower 25 and the second cam follower 26 are each formed in two, and the cam surfaces 29 and 35 that are in contact with the cam followers 25 and 26 are each provided with two inclined surfaces. Thus, there are four contact portions in the circumferential direction. Therefore, when there are three or more contact positions, the movable sheave 15 that is a member to be pressed is substantially pressed by the surface. Therefore, the posture of the movable sheave 15 is stabilized. Furthermore, the inclination angles of the inclined surfaces formed on the cam surfaces 29 and 35 can be made smaller than when three or more inclined surfaces are formed. In other words, the pressing force for pressing the movable sheave 15 can be increased according to the transmitted torque.

  In addition, as described above, the first cam follower 25 and the second cam follower 26 are not limited to those engaged by the spline, but the first cam follower 25 and the second cam follower 26 are integrally formed. There may be. Similarly, the first cylindrical cam 38 and the second cylindrical cam 39 may be integrally formed. Further, another cam follower and another cylindrical cam may be provided on the outer peripheral side of the second cam follower 26 and the second cylindrical cam 39. That is, it is only necessary that a plurality of cam followers and cylindrical cams shifted in the circumferential direction and the radial direction are formed, and the number thereof is not particularly limited. Further, the cam followers 25 and 26 or the cam surfaces 29 and 35 may be partially overlapped in the circumferential direction. In the above example, each cam follower is described as being configured to rotate integrally with the movable sheave and move in the axial direction. However, the cylindrical cam rotates integrally with the movable sheave. However, it may be configured to move in the axial direction.

  21 ... Torque cam mechanism, 25,26 ... Cam follower, 29,35 ... Cam surface, 33,34,27,28 ... Inclined surface, 41,42,43,44 ... Contact surface.

Claims (3)

A cylindrical cam member having a tip surface in the axial direction that is a cam surface curved in an uneven shape in the axial direction is attached to one of the pressing member and the pressed member that can rotate relative to each other, and the cam surface is attached to the cam surface. In the torque cam device in which a cam follower that is abutted and moved in the axial direction along the uneven shape of the cam surface is attached to one of the pressing member and the pressed member,
The cam surface includes a first cam surface having the concave portion and a convex portion, and a second concave portion or a convex portion formed so as to be shifted in a circumferential direction and a radial direction from the concave portion or the convex portion on the first cam surface. And at least a cam surface,
When the torque is transmitted to either the pressing member or the pressed member, the cam follower contacts the first cam surface and transmits the torque to the first cam follower and the second cam surface. A torque cam device comprising a second cam follower that abuts and transmits torque.   When torque is transmitted to the pressing member, the first cam surface and the first cam follower come into contact with each other and the pressed member is pressed in the axial direction, and the pressed member is pressed in the axial direction. 2. The structure according to claim 1, wherein the second cam surface and the second cam follower are in contact with each other in the same direction as the direction of the load applied to press the pressed member in the axial direction. The torque cam device described in 1.   The first cam surface has two recesses or projections formed at a distance from each other in the circumferential direction, and the first cam follower is formed on the two recesses or projections on the first cam surface. Two cam followers that contact each other and transmit torque are provided, and the second cam surface has two concave portions or convex portions that are spaced apart from each other in the circumferential direction, and the second cam follower 3. The torque cam device according to claim 1, further comprising: two cam followers that transmit torque by contacting two concave portions or convex portions on the second cam surface, respectively. 4.

Images