JP2010007777A - Continuously variable transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a continuously variable transmission capable of sufficiently constructing a maximum deceleration stage by precisely displacing a belt to a predetermined position when switching to the maximum deceleration stage. <P>SOLUTION: This continuously variable transmission 100 comprises a primary shaft 200, a primary pulley 250 including a fixed sheave 260 and a movable sheave 270 provided so as to enter or retreat from the fixed sheave 260, a secondary shaft 300, a secondary pulley 350 including a fixed sheave 360 and a movable sheave 370 provided so as to enter or retreat from the fixed sheave 360, a belt provided between the primary pulley 250 and the secondary pulley 350 and capable of transmitting a power between the primary pulley 250 and the secondary pulley 350, and at least one of a first friction material provided to the primary shaft 200 and capable of contacting the belt and a second friction material provided to the secondary shaft 300 and capable of contacting the belt. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a continuously variable transmission.

  Conventionally, various continuously variable transmissions have been proposed. For example, a belt-type continuously variable transmission described in Japanese Patent Application Laid-Open No. 2006-3000243 is a fixed sheave fixed to a pulley shaft, and a movable that is fitted to the pulley shaft so as not to be rotatable relative to the pulley shaft so as to be axially movable. A sheave and a partition member disposed on the back side of the movable sheave and fixed to the pulley shaft. Further, this belt type continuously variable transmission is provided with a structure in which the movable sheave is integrated with a fixed member including a pulley shaft by a wedge action at a position corresponding to the maximum gear ratio or the minimum gear ratio.

  A control device for a vehicle power transmission mechanism described in Japanese Patent Application Laid-Open No. 2004-176729 discloses a road state determination unit that determines continuity of a predetermined road state, and the power based on a determination result of the road state determination unit. Torque capacity control means for controlling the torque capacity of the transmission mechanism. And when the rotation change of a wheel arises according to a state, the torque capacity of a power transmission mechanism is controlled.

  A pulley for a continuously variable transmission described in Japanese Utility Model Laid-Open No. 5-14719 includes a fixed pulley and a movable pulley, and a surface treatment layer having a low friction coefficient is provided on a conical surface in contact with the V belt of the fixed pulley and the movable pulley. Is formed. Thereby, even if the wedge angle between the conical surfaces is small, the lifting force of the belt is ensured.

A transmission pulley structure of a continuously variable transmission described in Japanese Utility Model Publication No. 5-6247 is provided with a rotating shaft, a fixed pulley fixed to the rotating shaft, and a sliding movement on the rotating shaft via a bearing. And a movable pulley. The outer peripheral surface of the rotating shaft is a hard smooth surface. The bearing of the movable pulley has a steel ring part on the outer peripheral side, and a porous bronze layer is sintered inside the steel ring part, and a resin sliding layer impregnated with resin is further inside. Is formed. And the smooth surface by which the roller burnishing process was carried out is formed in the internal peripheral surface of a resin sliding layer. Japanese Patent Laid-Open No. 4-83953 also discloses a continuously variable transmission.
JP 2006-3000243 A JP 2004-176729 A Japanese Utility Model Publication No. 5-14719 Japanese Utility Model Publication No. 5-6247 Japanese Patent Laid-Open No. 4-83953

  However, in the belt-type continuously variable transmission described in Japanese Patent Application Laid-Open No. 2006-3000243, the belt does not return to the inner diameter side of the primary pulley when switching to the most decelerating step, and the best decelerating step is satisfactorily performed. There was a problem that it could not be built.

  The above-described problems are caused by the control device for the vehicle power transmission mechanism described in Japanese Patent Application Laid-Open No. 2004-176729, the pulley for continuously variable transmission described in Japanese Utility Model Laid-Open No. 5-14719, The same problem arises in the transmission pulley structure of the continuously variable transmission described in JP-A-6247 and the continuously variable transmission described in JP-A-4-83953.

  The present invention has been made in view of the problems as described above, and its purpose is to make the best speed reduction stage better when the belt is accurately displaced to a predetermined position when switching to the maximum speed reduction stage. It is to provide a continuously variable transmission that can be constructed.

  A continuously variable transmission according to the present invention includes a first rotary shaft that is rotatably provided, a first sheave provided on the first rotary shaft, and a first rotary shaft that is advanced and retracted relative to the first sheave. A first pulley including a second sheave that can be provided, a second rotary shaft that is provided to be spaced from the first rotary shaft, and a second pulley that is provided on the second rotary shaft. 3 sheaves and a second pulley including a fourth sheave provided on the second rotating shaft and capable of moving back and forth with respect to the third sheave, and provided between the first pulley and the second pulley. A belt capable of transmitting power between the pulley and the second pulley, a first friction material provided on the first rotating shaft and capable of contacting the belt, and a second friction provided on the second rotating shaft and capable of contacting the belt At least one of the materials.

  Preferably, the first friction material is accommodated in an annular first groove formed in a portion of the first rotating shaft located between the first sheave and the second sheave, and the first friction material is , Located on the radially inner side of the first rotating shaft with respect to the second sheave.

  Preferably, the second friction material is housed in an annular second groove formed in a portion of the second rotating shaft located between the third sheave and the fourth sheave, and the second friction material is , Located on the radially inner side of the second rotating shaft with respect to the fourth sheave.

  Preferably, the first friction material is provided, and the first friction material and the belt when the belt contacts the first friction material by adjusting the surface pressure between the third and fourth sheaves and the belt. And a second pulley adjusting mechanism capable of adjusting the frictional force between the first pulley and the second pulley.

  Preferably, the position of the second sheave relative to the first sheave can be adjusted, and the first pulley adjusting mechanism and the first and second pulley adjusting mechanisms capable of adjusting the position of the belt in the radial direction of the first rotating shaft. And a control unit capable of controlling the driving of. The control unit drives the first pulley adjustment mechanism so that the first friction material and the belt are in contact with each other, and the surface pressure between the belt and the first friction material is smaller than that in the normal running state. Thus, the shift control for driving the second pulley drive unit is selectively performed in accordance with a signal from the operation unit operated by the user.

  Preferably, the position of the second sheave with respect to the first sheave can be adjusted, and the first pulley adjusting mechanism capable of adjusting the position of the belt in the radial direction of the first rotating shaft, and the first friction material and the belt. A first friction material speed detecting unit capable of detecting a relative speed therebetween, and a first friction material surface pressure detecting unit capable of detecting a surface pressure between the first friction material and the belt. Further, the continuously variable transmission calculates a damage value of the first friction material based on output values from the first friction material speed detection unit and the first friction material surface pressure detection unit, and calculates the calculated damage. When it is determined that the value exceeds the threshold value, a control unit is further provided for controlling the drive of the first pulley adjusting mechanism so as to suppress contact between the first friction material and the belt.

  According to the continuously variable transmission according to the present invention, the belt can be accurately displaced to a predetermined position when switching to the most decelerating stage, so that the most decelerating stage can be satisfactorily constructed.

A 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 for 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 vehicle according to the present embodiment includes a continuously variable transmission 100, left and right front wheels 122, a shaft 123 that transmits power from continuously variable transmission 100 to front wheels 122, and a continuously variable transmission. ECU 125 for controlling the driving of machine 100. Further, the vehicle includes a shift lever 160 that is operated by a driver and selects a gear position, and a shift sensor 161 that senses the selected gear position and transmits a signal to the ECU 125. Continuously variable transmission 100 includes a transmission 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 speed change groove 130 is provided with a belt 390 provided between the primary pulley 250 and the secondary pulley 350 and capable of transmitting power from the primary pulley 250 to the secondary pulley 350.

  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. A shaft 123 is connected to the differential unit 150 that has received power transmission from the speed change mechanism unit 130, and the differential unit 150 changes the rotational speed of the left and right front wheels 122 during vehicle turning via the shaft 123. An equal driving force is transmitted to both wheels. The shaft 123 is provided with a torque sensor 120 capable of measuring the torque applied from the front wheel 122 to the shaft 123.

  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 flange that projects from the outer peripheral surface of primary shaft 200 toward the radially outer side of primary shaft 200.

  A portion of the collar portion of the fixed sheave 260 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. That is, the hydraulic actuator 290 can adjust the relative position of the movable sheave 270 with respect to 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 primary pulley 250, and is a cross-sectional view at the time of the maximum reduction ratio. As shown in FIG. 2, a friction member 210 is fixed to a portion of the peripheral surface of the primary shaft 200 positioned between the movable sheave 270 and the fixed sheave 260. The primary pulley 250 includes a relative speed sensor 180 that can detect a relative speed between the belt 390 and the friction member 210, and a pressure sensor 181 that can measure a surface pressure applied to the friction member 210 by the belt 390. ing. In addition, although the shape of the bottom part of the belt 390 is formed in the substantially flat surface shape, it is not restricted to this. For example, a plurality of belts 390 may be formed on the bottom surface of the belt 390 in the longitudinal direction of the belt 390 and spaced apart in the lateral direction (width direction) of the belt 390.

  FIG. 3 is a cross-sectional view showing the configuration of the secondary pulley 350, and is a cross-sectional view at the time of the maximum reduction ratio. Referring to FIG. 3 and FIG. 1, a friction member 220 provided in a portion located between the fixed sheave 360 and the movable sheave 370 on the outer peripheral surface of the secondary shaft 300 is provided. The secondary pulley 350 includes a relative speed sensor 182 that can detect a relative speed between the belt 390 and the friction member 220, and a pressure sensor 183 that can measure a surface pressure applied to the friction member 220 by the belt 390. . Here, FIG. 4 shows a state of the continuously variable transmission 100 at the maximum reduction ratio. Here, as shown in FIGS. 2 and 4, at the time of the most deceleration stage, the hydraulic sheave 270 and the fixed sheave 260 of the primary pulley 250 are largely separated from each other by driving the hydraulic actuator 290, so that the belt 390 The bottom and the friction member 210 come into contact with each other. As a result, power is transmitted to the belt 390 via the friction member 210.

  As shown in FIG. 3, at the time of the maximum reduction ratio, the hydraulic actuator 400 is driven so that the fixed sheave 360 and the movable sheave 370 come close to each other, and the belt 390 moves between the fixed sheave 360 and the movable sheave 370. Located on the outer periphery. The power is transmitted from the belt 390 to the secondary pulley 350 by contacting the side surface of the belt 390 with the power transmission surface 410 and the power transmission surface 411.

  Here, in FIG. 2 and FIG. 1, by setting the amount of oil supplied into the hydraulic cylinder of the hydraulic actuator 290 to 0 (L), for example, the movable sheave 270 is separated from the fixed sheave 260 greatly, The belt 390 can be brought into contact with the friction member 210.

  The friction member 210 is accommodated in an annular groove 211 formed on the peripheral surface of the primary shaft 200. The annular groove 211 extends from the root of the fixed sheave 260 toward the movable sheave 270.

  The friction member 210 is housed in the annular groove 211, so that the friction member 210 is positioned on the radially inner side of the primary shaft 200 with respect to the movable sheave 270. Thereby, when the movable sheave 270 moves along the axial direction of the primary shaft 200 so as to approach or separate from the fixed sheave 260, the movable sheave 270 is prevented from coming into contact with the friction member 210. .

  Further, since power is transmitted between the belt 390 and the primary pulley 250 at the time of the most deceleration stage, the power transmission surface 275 of the movable sheave 270, the belt, The surface pressure generated between the side surfaces of 390 is small. For this reason, the load applied to the movable sheave 270 can be reduced, and the rigidity and the like of the support member provided on the primary shaft 200 and supporting the movable sheave 270 can be suppressed.

  In the transmission according to the present embodiment, power is transmitted by contact of friction member 210 located on the radially inner side of primary shaft 200 with respect to movable sheave 270 and belt 390. For this reason, the maximum speed defined by the transmission according to the present embodiment is greater than the reduction ratio of the maximum speed reduction stage defined by the belt 390 being sandwiched between the power transmission surfaces 275 and 265 of the movable sheave 270 and the fixed sheave 260. The reduction ratio at the reduction stage is larger.

  FIG. 8 is a graph showing the gear ratio, belt clamping pressure, and torque when the belt 390 is brought into contact with the friction member 210.

  In FIG. 8, the belt 390 starts to contact the friction member 220 at time t1, and the belt 390 completely contacts the friction member 220 at time t2. The rate of change of the belt clamping pressure during the period from when the belt 390 starts to contact the friction member 210 to when the belt 390 completely contacts the friction member 210 is the belt clamping force when the belt 390 is brought close to the friction member 210. It is smaller than the rate of change of pressure.

  As described above, the ECU 125 controls the driving of the hydraulic actuator 400 so that the belt 390 can be brought into contact with the friction member 210 little by little, and the impact generated when the belt 390 comes into contact with the friction member 210 can be reduced. It has been.

  Even during kickdown, as shown in FIG. 8, the ECU 125 drives the hydraulic actuator 400 so that a large gear ratio can be used while reducing the engagement shock. Can be realized.

  The contact surface pressure between the friction member 210 and the belt 390 is set by the clamping pressure of the belt 390 in the secondary pulley 350. That is, a tensile force is applied to the belt 390 by the clamping pressure of the belt 390 in the secondary pulley 350, and the contact surface pressure between the belt 390 and the friction member 210 is determined by this tensile force.

  FIG. 5 is a diagram showing a state of the continuously variable transmission in FIG. 1 at the maximum speed increase ratio. FIG. 6 is a cross-sectional view of the primary pulley 250 at the maximum speed increase ratio, and FIG. 7 is a cross-sectional view of the secondary pulley 350 at the maximum speed increase ratio.

  As shown in FIG. 6, at the maximum speed ratio, the hydraulic actuator 290 is driven by a command from the ECU 125, and the movable sheave 270 approaches the fixed sheave 260. Then, the belt 390 is displaced toward the outer peripheral edge side of the primary pulley 250 and the fixed sheave 260.

  Here, as shown in FIG. 7, a friction member 220 is provided on the outer peripheral surface of the secondary shaft 300. The friction member 220 is fitted into an annular groove 221 formed on the peripheral surface of the secondary shaft 300, and the friction member 220 is located on the radially inner side of the secondary shaft 300 with respect to the movable sheave 370. . Thereby, even if the movable sheave 370 is displaced toward the fixed sheave 360, the contact between the friction member 220 and the movable sheave 370 is suppressed.

  The annular groove 221 extends from the root of the fixed sheave 360 toward the movable sheave 370. At the maximum speed ratio, the friction member 220 and the belt 390 come into contact with each other, and power is transmitted from the belt 390 to the secondary pulley 350 via the friction member 220.

  Here, since the friction member 220 is located on the radially inner side of the secondary shaft 300 with respect to the movable sheave 370, the maximum increase defined by the power transmission surfaces 410 and 411 between the fixed sheave 360 and the movable sheave 370. The speed ratio of the maximum speed ratio in the transmission according to the present embodiment is smaller than the speed ratio. Thereby, a wide range of the gear ratio can be secured.

  Further, since the power is transmitted between the friction member 220 and the belt 390 at the maximum speed ratio, the surface pressure generated between the side surface of the belt 390 and the power transmission surface 411 is kept small. It has been. For this reason, the rigidity etc. which are provided in the secondary shaft 300 and which support member 370 which supports movable sheave 370 can be suppressed low.

  In FIG. 1, the torque sensor 120 transmits a signal corresponding to the torque applied to the front wheel 122 to the ECU 125. ECU 125 calculates the torque applied to front wheel 122 based on the signal from torque sensor 120. When ECU 125 determines that the calculated torque is greater than the threshold value stored in ECU 125 in advance, the amount of oil supplied to hydraulic actuator 290 is set to 0 (L) (minimum amount of oil), for example. To do. As a result, the belt 390 and the friction member 210 provided on the primary shaft 200 are brought into contact with each other.

  Then, the ECU 125 controls the drive of the hydraulic actuator 400 so that the clamping pressure of the belt 390 in the secondary pulley 350 becomes, for example, a predetermined value smaller than the clamping pressure in the normal traveling state.

  As described above, the tension force applied to the belt 390 can be adjusted by adjusting the clamping force of the belt 390. By adjusting the tensile force of the belt 390, the maximum frictional force generated between the friction member 210 and the belt 390 can be adjusted. For example, the maximum frictional force generated between the friction member 210 and the belt 390 can be reduced as compared with that in the normal running state by making the pressure smaller than that in the normal running state.

  Then, when a large torque is applied from the ground to the continuously variable transmission 100 via the front wheels 122, the belt 390 slips on the friction member 210 and suppresses an excessive torque being applied to the continuously variable transmission 100. Can do.

  In addition, as a case where a large torque is applied from the ground via the front wheel 122, for example, a case where the vehicle jumps and landes on the ground again.

  Here, in the example described above, the belt 390 and the friction member 210 are brought into contact with each other, but the present invention is not limited to this.

  For example, when ECU 125 determines that the torque applied from front wheel 122 is equal to or greater than a predetermined torque, the amount of oil supplied to hydraulic actuator 400 is set to, for example, 0 (L), and belt 390 is attached to secondary shaft 300. You may make it contact the provided friction member 220. FIG. In this case, the ECU 125 adjusts the friction force generated between the friction member 220 and the belt 390 by adjusting the drive of the hydraulic actuator 290 and adjusting the clamping force of the belt 390 in the primary pulley 250. For example, the belt 390 is clamped with a pressure smaller than the clamping pressure of the primary pulley 250 in a normal traveling state.

  When a large torque is applied from the ground via the front wheel 122, the frictional force between the belt 390 and the friction member 220 is reduced, and the belt 390 slides on the friction member 220. Thereby, even if a large torque is applied from the ground, it is possible to suppress a large torque from being applied to the continuously variable transmission 100 via the belt 390.

  Here, in FIG. 2, the ECU 125 has the friction member 210 calculated beforehand by the surface pressure (p) generated between the friction member 210 and the belt 390 and the relative speed (v) of the friction member 210 and the belt 390. The threshold value (F1) of the damage value (F = f (p, v)) is stored.

  The damage value is calculated based on the signals from the relative speed sensor 180 and the pressure sensor 181. When ECU 125 determines that the calculated damage value is greater than threshold value F1, ECU 125 prohibits the shift mode in which belt 390 and friction member 210 are brought into contact with each other. Specifically, by increasing the lower limit value of the amount of oil supplied to the hydraulic actuator 290, the friction member 210 and the belt 390 can be prevented from contacting each other. The damage value is a numerical value for evaluating the degree of damage of the friction member 220. By sampling in advance by changing the relative speed or the surface pressure, the damage value is calculated from the relative speed (v) and the surface pressure (p). A damage value for evaluating the degree of damage of the friction member 220 is calculated.

  As a result, the belt 390 can be prevented from coming into contact with the worn or damaged friction member 220, and damage to the belt 390 and the friction member 220 can be suppressed. As shown in FIG. 3, the secondary pulley 350 also measures the relative speed sensor 182 capable of detecting the relative speed between the belt 390 and the friction member 220, and the surface pressure applied from the belt 390 to the friction member 220. Possible pressure sensor 183.

  Then, ECU 125 calculates a damage value of friction member 220 based on signals from relative speed sensor 182 and pressure sensor 183, and determines whether or not the threshold value is exceeded. When ECU 125 determines that the calculated damage value exceeds the threshold value, the shift mode in which belt 390 and friction member 220 are brought into contact is prohibited. Specifically, the belt 390 can be prevented from contacting the friction member 220 by adjusting the lower limit value supplied to the hydraulic actuator 400.

  In FIG. 1, the drive position, neutral position, parking position, and the like of the shift lever 160 are selected by the driver. Shift sensor 161 transmits to ECU 125 a signal corresponding to the shift position selected by shift lever 160. Then, ECU 125 drives continuously variable transmission 100 according to the selected shift position.

  Here, when the neutral position is selected in shift lever 160, shift sensor 161 transmits a signal to ECU 125 that the neutral position has been selected.

  When the ECU 125 receives the signal from the shift sensor 161, the ECU 125 drives the hydraulic actuator 290 to move the movable sheave 270 away from the fixed sheave 260 and bring the belt 390 into contact with the friction member 210.

  Further, the ECU 125 drives the hydraulic actuator 400 to adjust the clamping pressure of the belt 390 in the secondary pulley 350 so that it is lower than the clamping pressure in the normal traveling state.

  Thereby, the frictional force generated between the friction member 210 and the belt 390 can be reduced, and the belt 390 can slide on the friction member 210 to be in a neutral state. In addition, it can be set as a half clutch by adjusting the clamping force of the belt in the belt 390.

  As described above, the friction member 210 and the belt 390 can create a neutral state or a half-clutch state as described above, so that a forward / reverse gear switching mechanism or the like can be omitted, and the continuously variable transmission 100 can be made compact. Can be achieved. In the example shown in FIG. 1, the forward gear switching mechanism is provided.

  In the above example, the belt 390 is slid on the friction member 210. However, the present invention is not limited to this, and a neutral state or a half-clutch state is established by sliding the belt 390 on the friction member 220. You may do it.

  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 primary pulley, and is sectional drawing in the time of the maximum reduction ratio. It is sectional drawing which shows the structure of a secondary pulley, and is sectional drawing at the time of the maximum reduction ratio. 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 sectional drawing of the primary pulley at the time of the maximum speed increase ratio. It is sectional drawing of the secondary pulley at the time of the maximum speed increase ratio. It is a graph which shows the gear ratio, belt clamping pressure, and torque when a belt is made to contact a friction member.

Explanation of symbols

  100 continuously variable transmission, 120 torque sensor, 200 primary shaft, 210 friction member, 211 annular groove, 220 friction member, 221 annular groove, 250 primary pulley, 260 fixed sheave, 270 movable sheave, 290 hydraulic actuator, 300 secondary shaft, 350 Secondary pulley, 360 Fixed sheave, 370 Movable sheave, 390 belt, 400 Hydraulic actuator.

Claims (6)

A first rotation shaft provided rotatably,
A first sheave including a first sheave provided on the first rotating shaft and a second sheave provided on the first rotating shaft so as to be movable back and forth with respect to the first sheave;
A second rotary shaft provided at a distance from the first rotary shaft and rotatably provided;
A second pulley including a third sheave provided on the second rotating shaft, and a fourth sheave provided on the second rotating shaft and capable of moving forward and backward with respect to the third sheave;
A belt provided between the first pulley and the second pulley and capable of transmitting power between the first pulley and the second pulley;
At least one of a first friction material provided on the first rotating shaft and capable of contacting the belt; and a second friction material provided on the second rotating shaft and capable of contacting the belt;
A continuously variable transmission.   The first friction material is accommodated in an annular groove formed on a circumferential surface of the first rotation shaft, and the first friction material is radially inward of the first rotation shaft than the second sheave. The continuously variable transmission according to claim 1, which is located on a side.   The second friction material is accommodated in an annular groove formed on a peripheral surface of the second rotation shaft, and the second friction material is radially inward of the second rotation shaft than the fourth sheave. The continuously variable transmission according to claim 1 or 2, which is located on a side. The first friction material is provided;
A second pulley adjusting mechanism that can adjust a frictional force between the first friction material and the belt by adjusting a surface pressure between the third and fourth sheaves and the belt is further provided. The continuously variable transmission according to any one of claims 1 to 3. A first pulley adjusting mechanism capable of adjusting a position of the second sheave relative to the first sheave and capable of adjusting a position of the belt in a radial direction of the first rotating shaft;
A control unit capable of controlling the driving of the first and second pulley adjusting mechanisms;
The control unit drives the first pulley adjusting mechanism so that the first friction material and the belt are in contact with each other, and when the surface pressure between the belt and the first friction material is in a normal running state. 5. The continuously variable transmission according to claim 4, wherein shift control for driving the second pulley drive unit is selectively performed according to a signal from an operation unit operated by a user so that the second pulley drive unit is smaller. Machine. A first pulley adjusting mechanism capable of adjusting a position of the second sheave relative to the first sheave and capable of adjusting a position of the belt in a radial direction of the first rotating shaft;
The first friction material speed detector capable of detecting a relative speed between the first friction material and the belt;
A first friction material surface pressure detector capable of detecting a surface pressure between the first friction material and the belt;
A damage value of the first friction material is calculated based on output values from the first friction material speed detection unit and the first friction material surface pressure detection unit, and the calculated damage value is a threshold value. A controller that controls the drive of the first pulley adjusting mechanism so as not to contact the first friction material and the belt;
The continuously variable transmission according to claim 4 or 5, further comprising:

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