JP2009192018A - Continuously variable transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a continuously variable transmission capable of suppressing damage of the inner wall surface of an oil pressure chamber by suppressing contacting of a spring with the inner wall surface of the oil pressure chamber even if the spring is deformed by centrifugal force etc. during the operation. <P>SOLUTION: The continuously variable transmission includes a disc-shaped movable sheave 370 arranged able to advance and retreat to/from a stationary sheave 360, a piston 401 installed on the side of a secondary shaft 300 opposite the stationary sheave 360 about the movable sheave 370 and bounding the oil pressure chamber 403 in cooperation with the movable sheave 370, a resilient member 402 installed inside the chamber 403 in a position between the piston 401 and the movable sheave 370, and a protection member 700 having a higher hardness than the piston 401 installed in such a manner as covering the resilient member 402 outward in the radial direction of the secondary shaft 300 with respect to the resilient member 402 in a position between the piston 401 and the resilient member 402. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a continuously variable transmission.

  Conventionally, various continuously variable transmissions have been proposed. For example, a continuously variable transmission described in Japanese Patent Application Laid-Open No. 2005-299698 includes at least two hydraulic chambers: an outer diameter side hydraulic chamber that generates a belt clamping pressure acting on a movable sheave, and an inner diameter side hydraulic chamber. ing.

  A compression spring that biases the movable sheave is provided in the inner diameter side hydraulic chamber so as to generate a belt clamping pressure.

  A continuously variable transmission described in Japanese Patent Laying-Open No. 2006-77929 is provided in a friction transmission mechanism that transmits rotational power by a frictional force generated in association with hydraulic control in a cylinder chamber, and a friction transmission mechanism. And a centrifugal cancel chamber that cancels the centrifugal hydraulic pressure of the cylinder.

  The centrifugal cancel chamber is provided on the secondary movable pulley, and is defined by an extending portion extending in the axial direction, a fixed wall, and a centrifugal cancel piston. A spring is disposed between the secondary movable pulley and the fixed wall.

  A continuously variable transmission described in Japanese Patent Application Laid-Open No. 11-257448 includes a first conical plate pair and a second conical plate each having a conical plate which is movable in the axial direction and immovable in the axial direction. It has a pair and winding means arranged between the conical plate pair for torque transmission.

The continuously variable transmission includes a piston / cylinder unit that drives the pair of conical plates and can be tightened against the chain in the axial direction. Further, a coil spring is provided in the pressure chamber of the piston / cylinder unit, and a plate movable in the axial direction is pushed toward a plate which is not moved in the axial direction.
JP 2005-299698 A JP 2006-77929 A JP-A-11-257448

  In the continuously variable transmission described in JP-A-2005-299698, when the continuously variable transmission is driven, the spring is deformed by centrifugal force or the like, and the spring contacts the inner wall surface of the inner diameter side hydraulic chamber. In addition, there are problems such as damage to the inner wall surface of the inner diameter side hydraulic chamber. Also in the continuously variable transmission described in Japanese Patent Application Laid-Open No. 2006-77929, when the continuously variable transmission is driven, the spring is deformed by centrifugal force or the like. For example, the fixed wall and the spring are in contact with each other and fixed. Defects such as damage to the wall occur. Also in the continuously variable transmission described in Japanese Patent Laid-Open No. 11-257448, the coil spring is deformed by centrifugal force or the like, the inner surface of the pressure chamber contacts the spring, and the inner surface of the pressure chamber is damaged. Bad effects occur.

  The present invention has been made in view of the above problems, and its purpose is to ensure that the spring and the inner wall surface of the hydraulic chamber are in contact with each other even if the spring is deformed by centrifugal force or the like during driving. It is to provide a continuously variable transmission which is suppressed and damage of an inner wall surface of a hydraulic chamber is suppressed.

  A continuously variable transmission according to the present invention is arranged on a rotating shaft, a disc-shaped fixing member fixed to the rotating shaft, and a fixed member spaced apart in the center line direction of the rotating shaft. A disc-shaped movable member provided to be movable toward and away from the fixed member, and a rotary shaft provided on the opposite side of the fixed member with respect to the movable member, and in cooperation with the movable member, A hydraulic chamber defining member for defining the chamber; an elastic member disposed between the hydraulic chamber defining member and the movable member; and an elastic member on the radially outer side of the rotating shaft with respect to the elastic member. A protective part is provided so as to cover and is positioned between the hydraulic chamber defining member and the elastic member and having a higher hardness than the hydraulic chamber defining member. Preferably, the hardness of the protection part is smaller than the hardness of the elastic member. Preferably, the protection unit is attached to an inner surface located in the hydraulic chamber among the surfaces of the hydraulic chamber defining member. Preferably, a part of the protective portion is located between the end portion of the elastic member on the hydraulic chamber defining member side and the hydraulic chamber defining member, and the protective portion is placed on the inner surface of the hydraulic chamber defining member by the elastic member. Pressed and fixed. Preferably, the protection part is formed so as to protrude from a portion of the movable member located in the hydraulic chamber toward the opposite side of the movable member and to cover the elastic member.

  According to the continuously variable transmission according to the present invention, damage to the inner wall surface in the hydraulic chamber can be suppressed even if the elastic member is deformed by centrifugal force or the like.

The continuously variable transmission according to the present embodiment will be described with reference to FIGS.
Note that in the embodiments described below, when referring to the number, amount, and the like, the scope of the present invention is not necessarily limited to the number, amount, and the like unless otherwise specified. In the following embodiments, each component is not necessarily essential to the present invention unless otherwise specified. In addition, when there are a plurality of embodiments below, it is planned from the beginning to appropriately combine the features of each embodiment unless otherwise specified.

(Embodiment 1)
FIG. 1 is a sectional view showing a continuously variable transmission according to an embodiment of the present invention. Referring to FIG. 1, a belt type continuously variable transmission 100 is mounted on a vehicle. The continuously variable transmission 100 includes a speed change mechanism 130.

  The transmission mechanism unit 130 includes a drive-side primary shaft 200 to which rotational force is input from the engine, a driven-side secondary shaft 300 that outputs rotational force, a primary pulley 250 provided on the primary shaft 200, and a secondary shaft 300. And a secondary pulley 350 provided on the vehicle. The primary shaft 200 and the secondary shaft 300 are arranged in parallel with a space therebetween. The speed change mechanism 130 changes the ratio between the rotation speed of the primary shaft 200 and the rotation speed of the secondary shaft 300, that is, the gear ratio steplessly (continuously).

  The continuously variable transmission 100 includes a differential unit 150. The differential unit 150 is provided so as to be able to transmit power to the speed change mechanism unit 130. Differential unit 150 includes a ring gear 153, and ring gear 153 is coupled to secondary shaft 300 with gears 151 and 152 interposed therebetween. The differential unit 150 that has received power transmission from the speed change mechanism unit 130 transmits an equal driving force to both wheels while changing the rotational speed of the left and right wheels when the vehicle is turning.

  The continuously variable transmission 100 includes a case body 175. Case body 175 accommodates transmission mechanism 130 and differential unit 150 and forms the outer shape of continuously variable transmission 100. Case body 175 includes a transaxle housing 171, a transaxle case 170, and a transaxle rear cover 172. A transaxle housing 171 is arranged on the engine side with respect to the transaxle case 170, and a transaxle rear cover 172 is arranged on the opposite side.

  The case body 175 forms a speed change mechanism chamber 135. The transmission mechanism chamber 135 is formed by a transaxle case 170 and a transaxle rear cover 172. In the transmission mechanism chamber 135, a transmission mechanism unit 130 is accommodated.

  The primary pulley 250 rotates with the primary shaft 200 around the central axis of the primary shaft 200 that is a virtual axis. Primary pulley 250 includes fixed sheave 260, movable sheave 270, and hydraulic actuator 290 that drives movable sheave 270.

  The fixed sheave 260 is fixed to the primary shaft 200 and is fixed so as not to move in the circumferential direction and the axial direction with respect to the primary shaft 200.

  Fixed sheave 260 includes a disc-shaped flange that projects outward in the radial direction of primary shaft 200. A portion of the collar portion that faces the movable sheave 270 is a power transmission surface 265 that contacts the belt 390. The power transmission surface 265 is inclined so as to be separated from the movable sheave 270 as it goes outward in the radial direction of the primary shaft 200.

  The movable sheave 270 includes a cylindrical portion in which the primary shaft 200 is inserted, and a flange portion that is formed in the cylindrical portion and projects outward in the radial direction of the primary shaft 200.

  A portion of the collar portion of the movable sheave 270 that faces the fixed sheave 260 is a power transmission surface 275 that contacts the belt 390. The power transmission surface 275 is inclined away from the fixed sheave 260 as it goes radially outward from the primary shaft 200.

  A pulley groove 280 into which the belt 390 is fitted is defined by the power transmission surface 265 of the fixed sheave 260 and the power transmission surface 275 of the movable sheave 270.

  The hydraulic actuator 290 changes the groove width of the pulley groove 280 by moving the movable sheave 270 closer to or away from the fixed sheave 260.

  The secondary pulley 350 rotates with the secondary shaft 300 around the central axis of the secondary shaft 300 that is a virtual axis. The secondary pulley 350 includes a fixed sheave 360, a movable sheave 370, and a hydraulic actuator 400 that drives the movable sheave 370 so as to advance and retreat relative to the fixed sheave 360.

  FIG. 2 is a cross-sectional view showing the configuration of the secondary pulley 350. In FIG. 2, the upper side of the center shaft 301 indicates the secondary pulley 350 at the maximum speed increase ratio, and the lower side of the center shaft 301 indicates the secondary pulley 350 at the maximum speed reduction ratio. Referring to FIGS. 2 and 1, one end 470 of secondary shaft 300 is rotatably supported by transaxle rear cover 172 by bearing 420. The other end 471 of the secondary shaft 300 is rotatably supported by the transaxle housing 171 by a bearing 430.

  The secondary shaft 300 has a large diameter portion 453 extending from one end portion 470 toward the end portion 471 and a smaller diameter than the large diameter portion 453, and an intermediate diameter adjacent to the end portion 471 side with respect to the large diameter portion 453. A portion 452 and a small-diameter portion 451 that is smaller in diameter than the medium-diameter portion 452 and that is adjacent to the end-471 side with respect to the medium-diameter portion 452 are provided.

  A stepped portion 454 is formed at the boundary position between the large diameter portion 453 and the medium diameter portion 452, and a stepped portion 455 is formed at the boundary position between the medium diameter portion 452 and the small diameter portion 451. .

  Splines (engaging portions) 457 are formed on the outer surface of the medium diameter portion 452 and extend in the direction of the central axis 301 and are formed at intervals in the circumferential direction of the medium diameter portion 452.

  An oil passage 500 extending in the direction of the central axis 301 is formed inside the secondary shaft 300.

  A nut 460 is screwed to the end 470 of the secondary shaft 300. A bearing 420 is press-fitted into a portion of the secondary shaft 300 adjacent to the nut 460 on the end 471 side.

  The fixed sheave 360 is formed at a position adjacent to the end portion 471 with respect to the bearing 430 in the secondary shaft 300 and is integrally formed with the large-diameter portion 453.

  The fixed sheave 360 extends from the outer peripheral surface of the secondary shaft 300 toward the radially outer side, and is formed in a disk shape.

  The movable sheave 370 is provided on the secondary shaft 300 on the opposite side of the bearing 420 with respect to the fixed sheave 360 and spaced from the fixed sheave 360 in the direction of the virtual central axis 301 of the secondary shaft 300.

  The movable sheave 370 includes a cylindrical tube portion 371 into which the secondary shaft 300 is inserted, and a disk-shaped flange portion 372 that is connected to an end portion on the fixed sheave 360 side of the tube portion 371. I have.

  The flange portion 372 is formed in an annular shape, and the inner diameter of the flange portion 372 is formed to be larger than the inner diameter of the cylindrical portion 371. For this reason, a step portion 456 is formed at a boundary portion between the inner surface of the flange portion 372 and the inner surface of the cylindrical portion 371.

  The cylindrical portion 371 is formed in a cylindrical shape and extends toward the central axis 301. Splines (engagement portions) corresponding to the splines 457 are formed on the inner surface of the cylindrical portion 371 along the direction of the central axis 301. For this reason, the movable sheave 370 is provided so as to be movable in the direction of the central axis 301, but cannot be rotated in the circumferential direction of the secondary shaft 300.

  Of the outer peripheral surface of the movable sheave 370, the outer diameter of the flange portion 372 on the tube portion 371 side is larger than the outer diameter of the end portion of the tube portion 371 on the flange portion 372 side. For this reason, on the outer peripheral surface of the movable sheave 370, a stepped portion 458 is formed at the boundary portion between the cylindrical portion 371 and the flange portion 372.

  A portion of the surface of the flange portion 372 that faces the fixed sheave 360 is a power transmission surface 411 that is inclined so as to be separated from the fixed sheave 360 as it goes outward in the radial direction of the secondary shaft 300.

  A cylindrical cylinder portion 373 is formed on the side surface of the movable sheave 370 that is opposite to the power transmission surface 411. The cylinder portion 373 protrudes in the direction of the central axis 301.

  A portion of the surface of the fixed sheave 360 that faces the movable sheave 370 is a power transmission surface 410 that inclines away from the movable sheave 370 as it goes outward in the radial direction of the secondary shaft 300. A pulley groove 380 is defined by the power transmission surface 410 and the power transmission surface 411.

  The belt 390 is constituted by, for example, a flexible belt-shaped steel ring and a plurality of elements arranged in the longitudinal direction of the steel ring and fitted to the steel ring.

  The belt 390 functions as a power transmission member that frictionally contacts the inner peripheral surface of the pulley groove 280 of the primary pulley 250 and the inner peripheral surface of the pulley groove 380 of the secondary pulley 350. As a result, belt 390 transmits power between primary pulley 250 and secondary pulley 350.

  The hydraulic actuator 400 is provided on the side opposite to the fixed sheave 360 with respect to the movable sheave 370.

  The hydraulic actuator 400 is located on the opposite side of the fixed sheave 360 with respect to the movable sheave 370, and cooperates with the movable sheave 370 to define a piston (hydraulic chamber defining member) 401 that defines the hydraulic chamber 403, An elastic member 402 such as a coil spring that urges the movable sheave 370 so as to be separated from each other, and a protection member 700 disposed in the hydraulic chamber 403 are provided.

  The end portion on the end portion 471 side of the piston 401 is locked to the step portion 455, and the hydraulic reaction force applied to the hydraulic actuator 400 is supported by the stopper 481 via the stopper 481 and the gear 151. The stopper 480 is provided on the side opposite to the movable sheave 370 with respect to the hydraulic actuator 400, and the gear 151 is provided at a position adjacent to the stopper 480. The stopper 481 is screwed to the surface of the secondary shaft 300.

  FIG. 3 is a cross-sectional view showing a detailed configuration of the hydraulic actuator 400. As shown in FIG. 3, the piston 401 is located on the end portion 471 side, is engaged with the step 404, the bottom 404 is connected to the bottom 404, the peripheral wall 405 is connected to the bottom 404, and the peripheral wall 405 is connected. And a tapered portion 406 provided.

  The bottom portion 404 is formed with a hole portion into which the small diameter portion 451 is inserted, and is extended toward the radial direction of the secondary shaft 300. The peripheral wall portion 405 is connected to the outer peripheral edge portion of the bottom portion 404 and is formed in a cylindrical shape. The tapered portion 406 is connected to the end portion of the peripheral wall portion 405 and is formed so as to increase in diameter toward the flange portion 372 side. An end portion of the taper portion 406 on the movable sheave 370 side is provided to be slidable on the inner peripheral surface of the cylinder portion 373.

  The hydraulic chamber 403 is defined by a flange portion 372, a cylinder portion 373, and a piston 401. When oil is supplied into or discharged from the hydraulic chamber 403, the movable sheave 370 moves in the direction of the central axis 301, and the volume of the hydraulic chamber 403 varies. The elastic member 402 is attached to the cylindrical portion 371, and the elastic member 402 urges the flange portion 372 and the piston 401 so that the distance between them is large.

  The protection member 700 is attached to the inner surface that defines the hydraulic chamber 403 among the surfaces of the piston 401. The protective member 700 includes a bottom portion 702 extending along the inner surface of the bottom portion 404, a peripheral wall portion 703 extending along the inner surface of the peripheral wall portion 405, and a tapered portion 704 extending along the inner surface of the tapered portion 406. Yes. For this reason, the protection member 700 is disposed on the radially outer side of the secondary shaft 300 with respect to the elastic member 402, and is provided so as to cover the periphery of the elastic member 402. For this reason, the protection member 700 is located between the peripheral wall portion 405 and the bottom portion 404 of the piston 401 and the elastic member 402.

  One end of the elastic member 402 is supported by the step 458 via the seat plate 701. The other end of the protection member 700 is supported by the bottom 404 via the bottom 702 of the protection member 700. For this reason, the protection member 700 is pressed and fixed to the bottom 404 of the piston 401 by the elastic member 402.

  Here, the hardness (Vickers hardness) of the protective member 700 is higher than that of the piston 401 and lower than the Vickers hardness of the elastic member 402 and the movable sheave 370. The Vickers hardness of the protective member 700 is, for example, about 400 (Hv), and is formed by quenching iron. The elastic member 402 has a Vickers hardness of about 500 (Hv), for example, and the piston 401 has a Vickers hardness of about 250 (Hv), for example.

  The movable sheave 370 is made of iron or the like that has been subjected to carburizing and quenching or tempering, and the Vickers hardness of the movable sheave 370 is, for example, about 800 (Hv).

  FIG. 4 shows a state of the continuously variable transmission 100 at the maximum reduction ratio. FIG. 5 is a diagram showing a state of the continuously variable transmission in FIG. 1 at the maximum speed increase ratio. 4 and 5, the groove widths of pulley grooves 280 and 380 are variably controlled in accordance with the operation of hydraulic actuators 290 and 400. As a result, the wrapping radius (effective engagement diameter) of the belt 390 with respect to the primary pulley 250 and the secondary pulley 350 is changed to a large or small value, and the shift is executed.

  In FIG. 2, the rotation speed of the secondary pulley 350 and the secondary shaft 300 in the unit time becomes the largest at the maximum speed ratio, and the primary pulley 250 and the secondary shaft 300 in the unit time at the maximum speed reduction ratio. The rotation speed is the smallest.

  In FIG. 2, most of the cylindrical portion 371 enters the peripheral wall portion 405 of the piston 401 at the maximum speed increase ratio. As a result, the elastic member 402 mounted on the peripheral surface of the cylindrical portion 371 enters the protective member 700. Thereby, the periphery of the elastic member 402 is covered with the protective member 700.

  Here, at the maximum speed ratio, the movable sheave 370 and the secondary shaft 300 rotate at high speed. For this reason, the elastic member 402 also rotates in synchronization with the movable sheave 370, and the middle part of the elastic member 402 may bulge outward in the radial direction due to centrifugal force.

  At this time, since the protective member 700 is located on the outer peripheral side of the elastic member 402, it is possible to prevent the elastic member 402 and the piston 401 from being in direct contact with each other and damaging the piston 401. Furthermore, since the elastic member 402 has higher hardness than the protective member 700, the elastic member 402 can be prevented from being worn and broken.

  The protective member 700 is lower in hardness than the elastic member 402, but higher in hardness than the piston 401. Therefore, even if the elastic member 402 and the protective member 700 come into contact with each other, the protective member 700 is greatly worn or chipped. And the generation of foreign matter can be suppressed.

  In this embodiment, since the movable sheave 370 has a higher hardness than the elastic member 402, the cylindrical portion 371 is worn even if the cylindrical portion 371 and the elastic member 402 come into contact with each other while the movable sheave 370 is driven. Can be prevented from being damaged or damaged. The bottom portion 702 of the protection member 700 is disposed between the end portion on the end portion 471 side of the elastic member 402 and the bottom portion 404 of the piston 401, and wear and damage to the bottom portion 404 are suppressed.

  Since the protection member 700 is pressed and fixed to the bottom 404 of the piston 401 by the elastic member 402, the rotation speed of the protection member 700 approximates the rotation speed of the piston 401 and the movable sheave 370.

  Thereby, it can suppress that the protection member 700 rotates relatively with respect to the piston 401, and can suppress that big friction arises between the protection member 700 and the piston 401. FIG. And it can suppress that the protection member 700 is worn out or damaged.

  Here, an oil passage 501 and an oil passage 502 extending in the radial direction of the secondary shaft 300 are connected to the oil passage 500 with an interval in the direction of the central axis 301, and these oil passages 501 and 502 are It is connected to the hydraulic chamber 403.

  The oil discharged from the oil passage 502 reaches the inside of the hydraulic chamber 403 through a space between the inner peripheral surface of the cylindrical portion 371 and the outer peripheral surface of the medium diameter portion 452. For this reason, the friction between the cylinder part 371 and the intermediate diameter part 452 can be reduced, and the movable sheave 370 can move in the direction of the central axis 301 satisfactorily.

  The stepped portion 456 of the movable sheave 370 and the stepped portion 454 of the secondary shaft 300 are engaged with each other, whereby the minimum width of the secondary pulley 350 is defined.

  At the most reduction ratio, as shown in the lower side of FIG. 1, the movable sheave 370 is closest to the fixed sheave 360, and the cylindrical portion 371 of the movable sheave 370 is most protruded from the peripheral wall portion 405 of the piston 401. It becomes a state.

  On the other hand, the protective member 700 extends from the peripheral wall portion 405 of the piston 401 so as to reach the tapered portion 406, and covers most of the elastic member 402 even at the maximum reduction ratio, and the elastic member 402 is caused by centrifugal force. Even if it deform | transforms so that it may swell, it can suppress that the elastic member 402 and the piston 401 contact.

  The rotation speed per unit time of the secondary shaft 300 and the movable sheave 370 at the time of the maximum reduction ratio is smaller than the rotation speed of the secondary shaft 300 and the movable sheave 370 at the time of the maximum speed increase ratio, and the elastic member 402 at the time of the maximum reduction ratio. The deformation of is kept small.

  FIG. 6 is a perspective view showing a modified example of the protection member 700. The protective member 700 shown in FIG. 6 has a plurality of holes formed in the peripheral surface, and oil can flow between the inner peripheral surface side and the outer peripheral surface side of the protective member 700.

  Thereby, an oil film is easily formed between the outer peripheral surface of the protection member 700 and the inner peripheral surface of the piston 401, and friction between the protection member 700 and the piston 401 can be reduced. In the example shown in FIG. 6, a hole is formed in the protective member 700, but the protective member 700 may be made of a mesh-like material, for example.

  In addition, in the secondary pulley 350 which concerns on this Embodiment, since the centrifugal hydraulic pressure canceller chamber is not provided, the secondary pulley 350 can be comprised compactly.

  Here, the safety factor K is used as an index for the belt slip of the belt clamping pressure applied to the belt 490. The safety factor K is calculated by, for example, the well-known formula 1.

Here, P _OUT [MPa] indicates the belt clamping pressure control hydraulic pressure, that is, the belt tension control hydraulic pressure supplied to the hydraulic chamber 403 of the hydraulic actuator 400, and β indicates the centrifugal hydraulic pressure coefficient [MPa / (km / h) 2], V [km / h] is the vehicle speed, S _OUT [mm 2] is the pressure receiving area of the hydraulic chamber 403, W [N] is the load of the elastic member 402, T [Nm] is the transmission torque, θ [rad] is the flank angle of the fixed sheave 360 and the movable sheave 370, D [m] is the winding diameter of the primary pulley 250 of the belt 490, and μ [−] is the friction between the belt 490 and the secondary pulley 350. Each coefficient is represented.

  When the safety factor K is less than 1.0, slip occurs between the secondary pulley 350 and the belt 490. On the other hand, as the safety factor K is larger than 1.0, the clamping pressure applied to the belt 490 becomes excessive, the durability of the belt 490 is lowered, and the belt efficiency is lowered. In general, although the friction coefficient varies depending on the tolerance of the belt 490, the safety factor K is set to fall within a range of, for example, 1.0 to 1.5. It is preferable to set so as to be within the range of 2 to 1.5.

And, in the continuously variable transmission 100 according to the present embodiment, the cylinders of the clamping pressure control hydraulic pressures P _OUT and 403 so that the safety factor is in the above range even when the centrifugal hydraulic canceller chamber is not provided. The pressure receiving area S _OUT is set. In the present embodiment, the protection member 700 is separated from the piston 401. However, the protection member 700 is not limited to this, and heat treatment or the like is applied to the inner surface of the piston 401 so that the protection member 700 is placed inside the piston 401. It may be formed integrally with the surface.

(Embodiment 2)
FIG. 7 is a cross-sectional view of secondary pulley 350 of the continuously variable transmission according to Embodiment 2 of the present invention. In FIG. 7, the portion located on the upper side with respect to the central shaft 301 shows the secondary pulley 350 at the maximum speed increase ratio, and the portion positioned below with respect to the central shaft 301 shows the speed at the maximum speed reduction ratio. It is sectional drawing. In the example shown in FIG. 7, the movable sheave 370 includes a cylindrical portion 801 formed in a cylindrical shape, a flange portion 372 formed on the fixed sheave 360 side with respect to the cylindrical portion 801, and a cylindrical portion 801. On the other hand, it is provided with a cylindrical protective part 800 formed on the opposite side to the collar part 372.

  A spline that can be engaged with a spline 457 formed on the secondary shaft 300 is formed on the inner peripheral surface of the cylindrical portion 801.

  The protection unit 800 extends from the portion of the surface of the movable sheave 370 located in the hydraulic chamber 403 toward the side opposite to the fixed sheave 360 with respect to the movable sheave 370. The protection part 800 is formed in a cylindrical shape extending from the end of the cylinder part 801 toward the central axis 301.

  The inner diameter of the protection part 800 is larger than the inner diameter of the cylinder part 801, and the cylinder part 801 and the protection part 800 define an accommodation part 810 that can receive a part of the elastic member 402.

  One end of the elastic member 402 is supported by the end surface of the cylindrical portion 801, and at least a part of the elastic member 402 is accommodated in the accommodating portion 810. The other end of the elastic member 402 is located at the bottom 404. At the maximum speed increase ratio shown in the upper side of FIG. 7, the protection part 800 enters the peripheral wall part 405 of the piston 401. At this time, the protection part 800 reaches the bottom 404 side from the central part of the elastic member 402 in the direction of the central axis 301. The protection unit 800 is positioned so as to cover the elastic member 402 from the outer peripheral side of the elastic member 402.

  For this reason, even if the elastic member 402 is deformed so as to expand its diameter by centrifugal force, the elastic member 402 is supported by the protection unit 800, and the peripheral wall portion 405 of the piston 401 and the elastic member 402 are suppressed from contacting each other. ing.

  In the example shown in FIG. 7, the protection unit 800 is integrally formed with the movable sheave 370, the Vickers hardness of the movable sheave 370 is about 800 (Hv), and the Vickers hardness of the protection unit 800 is also It is about 800 (Hv) or less. On the other hand, the Vickers hardness of the elastic member 402 is about 500 (Hv), and the Vickers hardness of the protection unit 800 is higher than the Vickers hardness of the elastic member 402. Thereby, even if the protection part 800 supports the elastic member 402 and contacts the elastic member 402, wear of the protection part 800 can be suppressed. Also in the example shown in FIG. 7, the Vickers hardness of the protection part 800 is higher than the Vickers hardness of the piston 401. Also in the secondary pulley 350 shown in FIG. 5, the centrifugal hydraulic canceller chamber is not provided, and the secondary pulley 350 is made compact.

  Although the embodiment of the present invention has been described above, it should be considered that the embodiment disclosed this time is illustrative and not restrictive in all respects. The scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims. Furthermore, the above numerical values are examples, and are not limited to the above numerical values and ranges.

  The present invention is suitable for a continuously variable transmission.

It is sectional drawing which shows the continuously variable transmission in embodiment of this invention. It is sectional drawing which shows the structure of a secondary pulley. It is sectional drawing which shows the detailed structure of a hydraulic actuator. The state at the time of the maximum reduction ratio of the continuously variable transmission is shown. It is a figure which shows the state at the time of the maximum speed increase ratio of the continuously variable transmission in FIG. It is a perspective view which shows the modification of a protection member. It is sectional drawing of the secondary pulley of the continuously variable transmission which concerns on Embodiment 2 of this invention.

Explanation of symbols

  100 continuously variable transmission, 150 differential section, 151, 152 gear, 175 case body, 200 primary shaft, 250 primary pulley, 260, 360 fixed sheave, 265, 275 power transmission surface, 270, 370 movable sheave, 280, 380 pulley Groove, 290, 400 hydraulic actuator, 300 secondary shaft, 301 central axis, 350 secondary pulley.

Claims (5)

A rotation axis;
A disk-shaped fixing member fixed to the rotating shaft;
A disc-shaped movable member that is disposed on the rotary shaft at an interval in the center line direction of the rotary shaft with respect to the fixed member, and is provided so as to be able to advance and retreat toward the fixed member;
A hydraulic chamber defining member that is provided on the opposite side of the fixed member with respect to the movable member of the rotating shaft, and that defines a hydraulic chamber in cooperation with the movable member;
An elastic member disposed in the hydraulic chamber and provided between the hydraulic chamber defining member and the movable member;
The elastic member is provided on the radially outer side of the rotating shaft so as to cover the elastic member, and is positioned between the hydraulic chamber defining member and the elastic member, and has a hardness higher than that of the hydraulic chamber defining member. A high protection part,
A continuously variable transmission.   The continuously variable transmission according to claim 1, wherein a hardness of the protection portion is smaller than a hardness of the elastic member.   3. The continuously variable transmission according to claim 1, wherein the protection unit is mounted on an inner surface of the hydraulic chamber defining member positioned in the hydraulic chamber.   A part of the protective part is located between the end of the elastic member on the hydraulic chamber defining member side and the hydraulic chamber defining member, and the protective part is located inside the hydraulic chamber defining member by the elastic member. The continuously variable transmission according to claim 3, wherein the continuously variable transmission is fixed to the surface.   The protective part is formed so as to protrude toward the opposite side of the fixed member with respect to the movable member from a portion located in the hydraulic chamber of the movable member, and to cover the elastic member. The continuously variable transmission according to claim 1 or 2.

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