JP5187301B2 - Toroidal continuously variable transmission and continuously variable transmission - Google Patents

Description

  The present invention relates to a toroidal-type continuously variable transmission used as an automatic transmission for automobiles or as a transmission for various industrial machine devices, and to an improvement of a continuously variable transmission incorporating the toroidal-type continuously variable transmission. Specifically, by maintaining the contact surface pressure of each rolling contact portion appropriately at all times, a structure capable of preventing the occurrence of significant wear on each surface constituting each rolling contact portion is realized.

  The use of a toroidal continuously variable transmission as an automatic transmission for automobiles has been studied and implemented in part. In addition, as described in Patent Documents 1 to 9 and the like, it is conventionally known that a continuously variable transmission device is configured by combining a toroidal type continuously variable transmission and a planetary gear type transmission. 2 to 3 show the continuously variable transmission described in Patent Document 4 among them. This continuously variable transmission is a combination of a toroidal-type continuously variable transmission 1 and first to third planetary gear transmissions 2 to 4, and is supported concentrically and relatively rotatably. Further, it has an input shaft 5, a transmission shaft 6, and an output shaft 7. Then, in a state where the first and second planetary gear type transmissions 2 and 3 are spanned between the input shaft 5 and the transmission shaft 6, the third planetary gear type transmission 4 is connected to the transmission shaft 6. And the output shaft 7 are provided in a state of being spanned.

  Of these, the toroidal-type continuously variable transmission 1 includes a pair of input-side disks 8 a and 8 b, an integrated output-side disk 9, and a plurality of power rollers 10 and 10. Of these, the two input-side disks 8a and 8b have two axially spaced portions of the input shaft 5 in a state in which one axial side surfaces, which are toroidal curved surfaces each having a circular arc cross section, are opposed to each other. The position is concentric with each other and supports the rotation in synchronism with the input shaft 5 as free. Further, the output side disk 9 has both axial side surfaces, each of which is a toroidal curved surface having an arc cross section, at a position between the input side disks 8a and 8b around the intermediate portion of the input shaft 5. In a state of being opposed to one side surface in the axial direction of the input side discs 8a and 8b, the input side discs 8a and 8b are concentrically supported and freely supported for relative rotation with respect to the both input side discs 8a and 8b. .

  Further, a plurality of each of the power rollers 10 and 10 is sandwiched between both side surfaces in the axial direction of the output side disk 9 and one side surface in the axial direction of the both input side disks 8a and 8b. Each of the power rollers 10 and 10 has a partially spherical convex surface, and both the input side and output side of the power rollers 10 and 10 are sandwiched between the input side disks 8a and 8b and the output side disk 9. Transmission of power between the disks 8a, 8b, 9 can be freely performed. The power rollers 10 and 10 are rotatably supported on the inner surfaces of the trunnions 11 and 11. The trunnions 11 and 11 support the pivot shafts 12 and 12 provided at both ends of the trunnions 11 and 13b on support plates 13a and 13b installed in the casing 14 so as to be swingable and axially displaceable. . These support plates 13a and 13b are respectively supported by both ends of support columns 17 and 17 supported and fixed in the casing 14 via a connecting plate 15 and an actuator body 16.

  Further, the output side disk 9 is rotatably supported by a pair of thrust angular ball bearings 18 and 18 between the intermediate portions of the respective pillars 17 and 17 formed in an annular shape. Further, a base end portion (left end portion in FIG. 2) of the hollow rotary shaft 19 is spline engaged with the output side disk 9. The hollow rotary shaft 19 is inserted inside the input side disk 8a on the side far from the engine (right side in FIG. 2) so that power transmitted to the output side disk 9 can be taken out. Furthermore, a first sun gear for constituting the first planetary gear type transmission 2 at a portion protruding from the outer surface of the input side disk 8a at the tip end portion (the right end portion in FIG. 2) of the hollow rotary shaft 19. The gear 20 is fixed.

  On the other hand, a first carrier is provided between a portion protruding from the hollow rotary shaft 19 at the tip end portion (right end portion in FIG. 2) of the input shaft 5 inserted inside the hollow rotary shaft 19 and the input side disk 8a. 21 is provided so that the input side disk 8a and the input shaft 5 rotate in synchronization with each other. The planetary gears 22 to 24 are rotatably supported on the first carrier 21. Then, the planetary gear 24 on the outer diameter side and the planetary gears 22 and 23 on the inner diameter side are engaged with each other, and the planetary gears 22 and 23 on the inner diameter side are connected to the distal end portion (the right end portion in FIG. 2) of the hollow rotary shaft 19. The planetary gear 24 on the outer diameter side is freely rotatable around the first carrier 21 to the first sun gear 20 fixed to the second sun gear 25 fixed to the base end of the transmission shaft 6. Are respectively meshed with the first ring gear 26. Further, in order to transmit rotation between the input side disk 8a and the first carrier 21, the input side disk 8a and a part of the first carrier 21 are engaged.

  On the other hand, a second carrier 27 for constituting the third planetary gear type transmission 4 is coupled and fixed to a base end portion (left end portion in FIG. 2) of the output shaft 7. The second carrier 27 and the first ring gear 26 are coupled via a low speed clutch 28. Further, a third sun gear 29 is fixedly provided near the tip of the transmission shaft 6 (near the right end in FIG. 2). Further, a second ring gear 30 is disposed around the third sun gear 29, and a high speed clutch 31 is provided between the second ring gear 30 and the fixed portion of the casing 14, etc. Further, a plurality of planetary gears 32 and 33 arranged between the second ring gear 30 and the third sun gear 29 are rotatably supported on the second carrier 27. The planetary gears 32 and 33 mesh with each other, and the planetary gear 32 provided on the inner side in the radial direction of the second carrier 27 is provided on the third sun gear 29 and the planetary gear 33 provided on the outer side is provided on the first side. The two ring gears 30 are engaged with each other.

  In the case of the continuously variable transmission configured as described above, it is transmitted from the drive shaft 34 to the input shaft 5, and further from the input shaft 5 through the input disks 8 a and 8 b and the power rollers 10 and 10. The power transmitted to the integrated output disk 9 is taken out through the hollow rotary shaft 19. In the low speed mode in which the low speed clutch 28 is connected and the high speed clutch 31 is disconnected, the rotational speed of the input shaft 5 is kept constant by changing the gear ratio of the toroidal continuously variable transmission 1. In this state, the rotational speed of the output shaft 7 can be converted into forward rotation and reverse rotation with the stop state interposed therebetween. That is, in this state, the differential component between the first carrier 21 that rotates in the forward direction together with the input shaft 5 and the first sun gear 20 that rotates in the reverse direction together with the hollow rotation shaft 19 becomes the first ring. The gear 26 is transmitted to the output shaft 7 through the low speed clutch 28 and the second carrier 27. In this state, the output shaft 7 is stopped by setting the gear ratio of the toroidal continuously variable transmission 1 to a predetermined value, and the speed ratio of the toroidal continuously variable transmission 1 is increased from the predetermined value. By changing to the side, the output shaft 7 is rotated in the direction of retreating the vehicle. On the other hand, the output shaft 7 is rotated in the direction of moving the vehicle forward by changing the gear ratio of the toroidal type continuously variable transmission 1 from the predetermined value to the deceleration side.

  Further, in the high speed mode in which the low speed clutch 28 is disconnected and the high speed clutch 31 is connected, the output shaft 7 is rotated in a direction to advance the vehicle. That is, in this state, the first carrier 21 that rotates in the forward direction together with the input shaft 5 and the first sun gear 20 that rotates in the reverse direction together with the hollow rotating shaft 19 rotate according to the differential component. The rotation of the planetary gear 22 of the first planetary gear type transmission 2 is transmitted to the planetary gear 23 of the second planetary gear type transmission 3 via the planetary gear 24 on the outer diameter side, and the second sun gear The transmission shaft 6 is rotated via the gear 25. The third sun gear 29 provided at the tip of the transmission shaft 6, and the second ring gear 30 and the planetary gears 32, 33 constituting the third planetary gear type transmission 4 together with the third sun gear 29. The second carrier 27 and the output shaft 7 coupled to the second carrier 27 are rotated in the forward direction. In this state, the rotational speed of the output shaft 7 can be increased as the speed ratio of the toroidal type continuously variable transmission 1 is changed to the speed increasing side.

  During operation of the continuously variable transmission as described above, the inner side surfaces of the input side disks 8a and 8b and both axial side surfaces of the output side disk 9 and the power rollers 10 constituting the toroidal type continuously variable transmission 1 are provided. It is necessary to apply an appropriate surface pressure to the rolling contact portion (traction portion) with 10 peripheral surfaces. For this reason, in the case of the toroidal type continuously variable transmission 1 constituting the continuously variable transmission shown in FIGS. 2 to 3, the end of the input shaft 5 on the drive shaft 34 side and the periphery of the end A thrust generator 35 is provided between the disk 8b and the input side disk 8b. In the case of the structure shown in FIG. 2, the thrust generator 35 is a double piston type provided with a pair of hydraulic chambers 36a and 36b, each of which can be expanded and contracted in the axial direction. In the case of the structure provided with such a hydraulic thrust generating device 35, the surface pressure applied to each traction portion is controlled by controlling the pressure oil fed into the respective hydraulic chambers 36a, 36b. The value is adjusted to an appropriate value according to the magnitude of the torque passing through the step transmission 1. In addition, a preload spring 37 such as a disc leaf spring incorporated in the hydraulic chamber 36a can apply a minimum surface pressure to the traction portions even when no hydraulic pressure is introduced into the hydraulic chambers 36a and 36b. I have to.

  In the case of the continuously variable transmission incorporating the thrust generating device 35 and the preload spring 37 as described above, there is room for improvement when it is intended to ensure both transmission efficiency and durability. This is because, in the case of a continuously variable transmission provided with the low speed clutch 28 and the high speed clutch 31, when switching between the low speed mode and the high speed mode based on the connection / disconnection of the both clutches 28, 31, This is due to the fact that the torque passing through the toroidal type continuously variable transmission 1 becomes small (substantially zero) even though the power rollers 10 and 10 are rotating at high speed. That is, when switching between the low speed mode and the high speed mode, the torque passing through the toroidal-type continuously variable transmission 1 is maintained in order to keep both the clutches 28 and 31 connected, albeit for a short time. Become scarce. In this way, when the torque passing through the toroidal-type continuously variable transmission 1 is very small, the thrust generated by the thrust generator 35 (pressing force) is prevented from the occurrence of slippage in each traction section. ) Is negligible.

  On the other hand, since the switching between the low speed mode and the high speed mode is performed while the toroidal type continuously variable transmission 1 is in the maximum deceleration state, the rotational speeds of the power rollers 10 and 10 are very high. When the power rollers 10 and 10 are rotating at high speed, the revolution of the balls 39 and 39 constituting the thrust ball bearings 38 and 38 that rotatably support the power rollers 10 and 10 is performed. The speed is increased, and the centrifugal force acting on each of these balls 39 is increased. As a result, these balls 39 are pressed against the inner ring raceway 40 and the outer ring raceway 41 constituting the thrust ball bearings 38, 38 on the radially outer side of the power rollers 10, 10. In this state, the thrust generated by the thrust generating device 35 is reduced. As a result, when the surface pressure related to the load acting direction (contact angle direction) of the balls 39 and 39 decreases, the balls 39 and 39 It will be in a state of revolving without rotating. That is, the gyro slip occurs beyond the so-called gyro limit. When such gyro slip occurs, significant wear occurs at the contact portions between the rolling surfaces of the balls 39, 39 and the inner ring raceway 40 and the outer ring raceway 41, and the toroidal continuously variable transmission 1 is incorporated. This is a cause of reducing the durability of the continuously variable transmission.

  The above explanation is based on the assumption that the torque (passing torque) passing through the toroidal continuously variable transmission is small while the power roller constituting the toroidal continuously variable transmission is rotating at high speed. The case where the continuously variable transmission is configured by combining the step transmission with the planetary gear type transmission has been described. However, the state where the passing torque is small while the power roller is rotating at a high speed also occurs in the toroidal type continuously variable transmission alone. In other words, when this toroidal continuously variable transmission is used as an automatic transmission for an automobile, the accelerator pedal is suddenly stopped from a state where the accelerator pedal is depressed and suddenly accelerated. In this state, the above-described state occurs at the moment of shifting from the acceleration state to the deceleration state by the engine brake, although it is a short time. Also in this case, gyro slip occurs unless any countermeasure is taken.

  In any case, in order to prevent the durability from being lowered due to gyro slip, even if the elasticity of the preload spring 37 is increased and the hydraulic pressure introduced into the thrust generator 35 is low, It is conceivable to ensure the surface pressure in the contact angle direction of the balls 39, 39. However, in this case, the surface pressure becomes excessive when the value of the passing torque is small and the rotation speed of the power rollers 10 and 10 is low. As is well known, the resistance of the rolling contact portion increases as the surface pressure increases, and as a result, the power transmission efficiency decreases. Therefore, it is not preferable to increase the elasticity of the preload spring 37 in terms of ensuring low torque and efficiency during low rotation.

  Patent Document 10 discloses a technique for increasing the hydraulic pressure introduced into a hydraulic chamber provided in a hydraulic thrust generator in accordance with the rotational speed of each disk, and suppressing the gyro moment acting on the thrust ball bearing for the power roller. Is described. However, with such a structure described in Patent Document 10, it is difficult to suppress gyro-slip that occurs when switching between the low speed mode and the high speed mode in the continuously variable transmission as the object of the present invention. Furthermore, Patent Document 11 describes a technique for improving the gyro limit and suppressing gyro slip by devising the shape of the raceway surface and the material of the ball of the thrust ball bearing for the power roller. It is difficult to suppress the gyroscopic slip that occurs under the above conditions.

  In consideration of slip prevention at each traction section, even when the passing torque is small, the surface pressure of each traction section may be set to be equal to or higher than the pressure at which the traction oil is solidified (glass transition pressure). Conceivable. However, even when each of the power rollers 10 and 10 is rotating at high speed, in order to reliably prevent the gyro slip, the surface pressure of each of the traction portions must be larger than the glass transition pressure. It may not be possible. Therefore, even in consideration of securing the glass transition pressure, consideration for reliably preventing the gyro slip is necessary.

JP-A-6-174033 JP 2000-220719 A JP 2002-139124 A JP 2004-84712 A US Pat. No. 5,607,372 US Pat. No. 6,059,658 US Pat. No. 6,099,431 US Pat. No. 6,358,178 JP 2006-348888 A JP 2004-347071 A JP-A-11-72153

  In view of the circumstances as described above, the present invention provides each rolling contact portion, that is, a rolling contact portion (traction portion) between a peripheral surface of each power roller and a side surface of each disk, and each of these power rollers is rotatable. By maintaining the contact surface pressure of the rolling contact part inside the thrust ball bearing for proper support at all times, a structure that can prevent the occurrence of significant wear on each surface constituting each rolling contact part is realized. Invented accordingly.

Of the toroidal type continuously variable transmission and continuously variable transmission of the present invention, the toroidal type continuously variable transmission according to claim 1 is similar to the conventionally known toroidal type continuously variable transmission, and the input side disk. And an output side disk, a plurality of trunnions, a plurality of power rollers, a thrust generator, and a controller.
Among these, the input side disk and the output side disk are supported concentrically and rotatably in a state where the inner side surfaces, which are concave surfaces each having an arcuate cross section, are opposed to each other. Each trunnion swings about a pivot that is twisted with respect to the central axes of the input and output disks.
Each of the power rollers has a spherical convex surface, and a support shaft supported in a state protruding from the inner side surface of each trunnion and an inner portion of each trunnion. Via a thrust ball bearing provided between the trunnion and the trunnion, the trunnion is rotatably supported on the inner side surface, and is sandwiched between the input side disk and the output side disk.
Further, the thrust generating device is of a hydraulic type, and generates a thrust in a direction in which the input side disk and the output side disk are brought close to each other as the hydraulic pressure is introduced into the hydraulic chamber.
Furthermore, the controller controls the hydraulic pressure to adjust the thrust generated by the thrust generator.

  In particular, in the toroidal type continuously variable transmission of the present invention, the controller obtains a first target value necessary for power transmission between the input side disk and the output side disk; Compare the first and second target values with a function for obtaining the second target value required to prevent the balls constituting the thrust ball bearing from revolving without rotating, and a large target value. And a function of introducing a hydraulic pressure necessary for generating a thrust according to the pressure into the hydraulic chamber.

  A continuously variable transmission according to the present invention includes an input shaft, an output shaft, a toroidal continuously variable transmission, a planetary gear type transmission, and a connection between the toroidal type continuously variable transmission and the planetary gear type transmission. And a clutch device for switching the power transmission state. Of these, the toroidal continuously variable transmission is the toroidal continuously variable transmission as described above.

  According to the toroidal-type continuously variable transmission and continuously variable transmission of the present invention configured as described above, the rolling contact portion (traction portion) between the peripheral surface of each power roller and the side surface of each disk, and each of these powers The contact surface pressure of the rolling contact portion inside the thrust ball bearing for rotatably supporting the roller can always be maintained appropriately. And it can prevent that remarkable abrasion generate | occur | produces on each surface which comprises each of these rolling contact parts.

The flowchart which shows the function used as the characteristic of this invention. Sectional drawing which shows an example of the continuously variable transmission used as the object of this invention. AA sectional drawing of FIG.

  The toroidal type continuously variable transmission and continuously variable transmission of the present invention are characterized by a hydraulic thrust for ensuring the surface pressure of the rolling contact portion (traction portion) between the peripheral surface of each power roller and the side surface of each disk. In addition to ensuring the surface pressure required for the traction section, the hydraulic pressure introduced to the generator is also controlled from the surface that prevents the gyroscopic sliding from occurring in the thrust ball bearing that rotatably supports the power rollers. In the point. In addition, regarding the structure of the toroidal continuously variable transmission and the continuously variable transmission itself, various conventional toroidal continuously variable transmissions including one example of the conventional structure shown in FIGS. Since it is the same as the continuously variable transmission, the description thereof will be omitted or simplified, and the function of the controller for controlling the hydraulic pressure introduced into the hydraulic chamber of the thrust generator, which is a feature of the present invention, will be described below with reference to FIG. 1 will be described with reference to FIG.

  A controller for controlling the hydraulic pressure introduced into the hydraulic chambers 36a and 36b (see FIG. 2) of the hydraulic thrust generator 35 in the toroidal type continuously variable transmission and continuously variable transmission of this example is shown in FIG. As shown in FIG. 1, first, in Step 1, the first target value (power transmission) required for power transmission between the input side disks 8a and 8b and the output side disk 9 (see FIG. 2) is performed by the first function. The target loading pressure A) required for This first target value passes through the toroidal-type continuously variable transmission 1 (see FIGS. 2 to 3), as is widely known in the technical field of toroidal-type continuously variable transmissions and continuously variable transmissions. It is obtained from the torque (passing torque), the rotational speed of the drive shaft 34 (see FIG. 2), the traction coefficient of the traction section, and the like. The passing torque is obtained from an engine control computer or the like, the drive torque of the drive shaft 34, the transmission ratio of the toroidal-type continuously variable transmission 1, the low speed and high speed clutches 28, 31 (see FIG. 2). The traction coefficient is obtained from the type of traction oil present in the casing 14 (see FIGS. 2 to 3) and the temperature of the traction oil.

  The controller obtains the target loading pressure A necessary for power transmission in step 1 and then in step 2, the balls 39, 39 (see FIG. 3) constituting the thrust ball bearing 38 do not rotate. A second target value (necessary target loading pressure B required from the gyro limit load) required to prevent the revolving state is obtained. This second target value is obtained from the revolution speed of each of the balls 39, 39 determined by the rotational speed of the power rollers 10 and 10 (see FIG. 3) rotatably supported by the thrust ball bearing 38. The rotational speeds of the power rollers 10 and 10 are obtained from the rotational speed of the drive shaft 34 and the gear ratio of the toroidal continuously variable transmission 1. The operation (calculation) for obtaining the rotational speed of each of the power rollers 10 and 10 based on these and further for obtaining the gyro limit load based on the revolution radius and weight of each of the power rollers 10 and 10 is complicated. For this reason, continuing this operation during the operation of the toroidal-type continuously variable transmission 1 (a continuously variable transmission incorporating the toroidal-type continuously variable transmission 1) makes the load on the controller (ECU) excessive, and the hydraulic chamber 36a. , 36b may cause a delay in the control of the hydraulic pressure introduced into 36b. Therefore, based on a map (matrix) created in advance, a hydraulic pressure with a little margin (slightly higher than actually required) is obtained, and the obtained hydraulic pressure is set as the second target value. This is effective in eliminating the control delay.

  If the target loading pressure A required for power transmission is obtained in the step 1 and the necessary loading pressure B is obtained from the gyro limit load in the step 2, these target loading pressures A and B are obtained in the next step 3. Compare the size of. When the target loading pressure A required for power transmission is equal to or higher than the target loading pressure B required from the gyro limit load, the required loading pressure is set as the target loading pressure A required for power transmission in step 4, and this target A loading pressure A is introduced into the hydraulic chambers 36a and 36b. As a result, the discs 8a and 10b are not slipped excessively at rolling contact portions (traction portions) between the peripheral surfaces of the power rollers 10 and 10 and the inner surfaces of the input side discs 8a and 8b and the output side disc 9. , 8b, power transmission between the disks 9 becomes possible. At the same time, the thrust ball bearing 38 prevents gyro slip.

  On the other hand, when the target loading pressure B required from the gyro limit load is larger than the target loading pressure A required for power transmission, in step 5, the required loading pressure is changed from the gyro limit load to the required target loading pressure B. The target loading pressure B is introduced into the hydraulic chambers 36a and 36b. As a result, with respect to the rolling contact portions between the balls 39, 39 constituting the thrust ball bearing 38 and the inner ring raceway 40 and the outer ring raceway 41 (see FIG. 3), the thrust load bearing direction (contact angle direction) is related. The contact pressure becomes sufficiently high. As a result, the so-called gyro-slip, in which the balls 39, 39 revolve without rotating, is prevented from occurring, and excessive wear is not generated at each portion of the thrust ball bearing 38.

  According to the toroidal type continuously variable transmission and continuously variable transmission of this example configured as described above, the rolling contact between the peripheral surfaces of the power rollers 10 and 10 and the inner surfaces of the disks 8a, 8b and 9 is achieved. The contact surface pressure of the rolling contact portion inside the thrust ball bearing 38 for rotatably supporting the portion (traction portion) and the power rollers 10 and 10 can always be maintained appropriately. That is, the power rollers 10 and 10 rotate at a high speed when the load is light (when the transmission torque is small) as well as the power can be transmitted without causing excessive slip at the traction portions (rolling contact portions). In this state, it is possible to prevent an excessive slip from occurring inside the thrust ball bearing 38. As a result, it is possible to prevent the occurrence of significant wear on each surface constituting each rolling contact portion while preventing an increase in rolling resistance (decrease in transmission efficiency) associated with application of excessive surface pressure.

  A feature of the present invention is a toroidal-type continuously variable transmission equipped with a hydraulic thrust generating device. This thrust generating device generates a thrust so that the thrust generated by the thrust generating device is not insufficient and a margin is not excessive. This is to control the hydraulic pressure introduced into the hydraulic chamber of the apparatus. The structure of the hydraulic thrust generator is not limited to the double piston type as shown, but may be a single piston type. Furthermore, the present invention can be applied to a case where the toroidal type continuously variable transmission is implemented as a single unit in addition to a case where the toroidal type continuously variable transmission and the planetary gear type transmission are combined as a continuously variable transmission. .

DESCRIPTION OF SYMBOLS 1 Toroidal type continuously variable transmission 2 1st planetary gear type transmission 3 2nd planetary gear type transmission 4 3rd planetary gear type transmission 5 Input shaft 6 Transmission shaft 7 Output shaft 8a, 8b Input side disk 9 Output side disk DESCRIPTION OF SYMBOLS 10 Power roller 11 Trunnion 12 Pivot shafts 13a, 13b Support plate 14 Casing 15 Connection plate 16 Actuator body 17 Strut 18 Thrust angular ball bearing 19 Hollow rotating shaft 20 First sun gear 21 First carrier 22 Planetary gear 23 Planetary gear 24 Planetary gear 25 Second sun gear 26 First ring gear 27 Second carrier 28 Low speed clutch 29 Third sun gear 30 Second ring gear 31 High speed clutch 32 Planetary gear 33 Planetary gear 34 Drive shaft 35 Thrust generator 36a, 36b Hydraulic chamber 37 Preload spring 38 Thrust ball bearing 39 Ball 40 Inner ring Track 41 Outer ring track

Claims (2)

An input side disk and an output side disk that are supported concentrically and rotatably in a state in which the inner side surfaces, which are concave surfaces each having a circular arc shape, are opposed to each other, and these input side disk and output side disk A plurality of trunnions that swing about a pivot that is twisted with respect to the central axis of the shaft, a support shaft that is supported in an intermediate portion of each trunnion in a state of protruding from the inner surface of each trunnion, and each trunnion Respective peripheral surfaces that are rotatably supported on the inner side surface of each trunnion via a thrust ball bearing provided between the inner side surface and the input side disc and the output side disc. A plurality of power rollers having a spherical convex surface, and in a direction in which the input side disk and the output side disk come close to each other with the introduction of hydraulic pressure into the hydraulic chamber. Generates a force, a hydraulic thrust generating apparatus, for adjusting the thrust the thrust generator is generated, in the toroidal type continuously variable transmission in which and a controller for controlling the hydraulic pressure,
The controller has a function of obtaining a first target value necessary for power transmission between the input side disk and the output side disk, and each ball constituting the thrust ball bearing revolves without rotating. Compares the first and second target values with the function for obtaining the second target value necessary to prevent the state, and supplies the hydraulic pressure necessary to generate thrust according to the large target value in the hydraulic chamber. A toroidal-type continuously variable transmission characterized in that it is equipped with a function to be introduced. Input shaft, output shaft, toroidal continuously variable transmission, planetary gear transmission, and clutch device for switching the power transmission state between these toroidal continuously variable transmission and planetary gear transmission And
Of these, the toroidal continuously variable transmission has an input side disk and an output side that are supported concentrically and rotatably, with the inner side surfaces of each concave surface having an arcuate cross section facing each other. A disc, a plurality of trunnions that swing about a pivot that is twisted with respect to the center axis of the input side disc and the output side disc, and an intermediate portion of each trunnion protrudes from the inner surface of each trunnion The input side disk and the output side disk are rotatably supported on the inner side surface of each trunnion via a support shaft supported in a state and a thrust ball bearing provided between the inner side surfaces of each trunnion. A plurality of power rollers each having a spherical convex surface sandwiched between them, and the input side disk and the output along with the introduction of hydraulic pressure into the hydraulic chamber A stepless generator comprising a hydraulic thrust generating device that generates thrust in a direction in which the disk approaches each other, and a controller that controls the hydraulic pressure to adjust the thrust generated by the thrust generating device. In the transmission,
The controller has a function of obtaining a first target value necessary for power transmission between the input side disk and the output side disk, and each ball constituting the thrust ball bearing revolves without rotating. Compares the first and second target values with the function for obtaining the second target value necessary to prevent the state, and supplies the hydraulic pressure necessary to generate thrust according to the large target value in the hydraulic chamber. A continuously variable transmission characterized by having a function to be introduced into the vehicle.

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