JP5060383B2 - Continuously variable transmission - Google Patents

Description

  The present invention relates to a continuously variable transmission, and more particularly to a so-called toroidal continuously variable transmission in which a gear ratio is changed by a movement of a power roller disposed between an input disk and an output disk. .

  In general, in order to transmit a driving force from an internal combustion engine or an electric motor as a driving source, that is, an output torque to a road surface under an optimum condition according to a traveling state of the vehicle, a transmission is provided on the output side of the driving source. Is provided. This transmission includes a continuously variable transmission that controls the gear ratio steplessly (continuously) and a stepped transmission that controls the gear ratio stepwise (discontinuously). Here, in such a continuously variable transmission, so-called CVT (CVT: Continuously Variable Transmission), torque is transmitted between the respective disks via a power roller sandwiched between the input disk and the output disk. There is a so-called toroidal continuously variable transmission in which a power roller is tilted to change a gear ratio.

  This toroidal-type continuously variable transmission is configured by sandwiching a rotating means such as a power roller whose outer peripheral surface is a curved surface corresponding to the toroidal surface between an input disk and an output disk having a toroidal surface. Torque is transmitted using the shear force of the oil film of the traction fluid formed between the input disk, the output disk, and the power roller. The power roller is rotatably supported by a trunnion. The trunnion can be swung around a swing shaft, and, for example, can be placed in a transmission control hydraulic chamber with respect to a piston provided in the trunnion. The shift control pressing force is applied by the hydraulic pressure of the supplied hydraulic oil so as to be movable in the direction along the swing shaft.

  Accordingly, the power roller supported by the trunnion moves from the neutral position with respect to the input disk and the output disk to the shift position together with the trunnion. At this time, a tangential force acts between the power roller and the disk to generate a side slip, and the power roller swings, that is, tilts around the swing axis with respect to the input disk and the output disk. As a result, the gear ratio which is the rotation speed ratio between the input disk and the output disk is changed. The speed ratio, which is the rotation speed ratio between the input disk and the output disk, is determined based on the angle at which the power roller tilts with respect to the input disk and the output disk, that is, the tilt angle. It is determined based on an integral value of a stroke amount (offset amount) as a movement amount from the neutral position of the power roller to the shift position side.

  In such a conventional toroidal continuously variable transmission, lubrication and cooling are required to prevent wear and seizure of each member, and traction fluid is supplied as lubricating oil. In this case, since the torque is transmitted using the shear force of the oil film of the traction fluid formed between the input disk, the power roller, and the output disk, the traction fluid generates an oil film that separates the disk and the roller. The ability and the property (large traction force) that the generated oil film can transmit a large force are required.

  By the way, an oil pump for supplying traction fluid to each member is driven in synchronization with the engine. On the other hand, this traction fluid has a higher viscosity at low temperatures than a general traction fluid. Therefore, when the engine is cold started, the oil pump sucks and discharges high-viscosity traction fluid, which requires excessive driving torque and a large load on the oil pump. .

  Therefore, for example, in the power steering pump disclosed in Patent Document 1 below, a communication passage that communicates the suction chamber and the discharge chamber is provided, an oil passage that communicates from the communication passage to the suction chamber is provided, and an orifice is provided in the communication passage. A spring is provided that movably supports the spool valve and urges the spool valve in the closing direction of the oil passage. At the time of starting the pump, only when the viscosity of the hydraulic oil is large due to low temperature, the orifice is made to function as a throttle, so that the spool valve is opened and a part of the hydraulic oil in the discharge chamber is returned from the oil passage to the suction chamber. Yes.

Japanese Utility Model Publication No. 05-026726

  In the power steering pump described in Patent Document 1 described above, when the viscosity of the hydraulic oil is large due to low temperature when the pump is started, the spool valve is opened by causing the orifice to function as a throttle. In this case, in this conventional pump structure, the differential pressure is generated only when the hydraulic oil flows into the orifice. As a result, the spool valve is opened to return the hydraulic oil in the discharge chamber from the oil passage to the suction chamber. However, the traction fluid used in toroidal continuously variable transmission pumps is particularly viscous at low temperatures, so the pressure increases before hydraulic fluid flows from the suction chamber to the orifice, requiring excessive driving torque. At the same time, a large load acts on the oil pump.

  In addition, during normal operation of the engine where the temperature of the hydraulic oil has increased, the viscosity of the hydraulic oil becomes low, and when the engine rotates at a high speed, a large amount of hydraulic oil flows from the suction chamber to the orifice, where a differential pressure is generated and the spool The valve is opened to reduce the load on the oil pump. However, in the conventional pump structure, the spool valve is opened according to the viscosity of the hydraulic oil. Therefore, if the opening pressure of the spool valve is set so that a large load does not act on the oil pump at a low temperature, the spool is heated at a high temperature. The pressure threshold for opening the valve increases, and it becomes difficult to suppress the load of the oil pump.

  The present invention solves such problems, and an object of the present invention is to provide a continuously variable transmission that improves the durability by reducing the load of the oil pump.

In order to solve the above-described problems and achieve the object, the continuously variable transmission of the present invention contacts an input disk to which driving force from the engine is transmitted and an output disk to transmit the driving force to the wheels. In a toroidal continuously variable transmission having a hydraulic control device that hydraulically controls a gear ratio, which is a rotation speed ratio between the input disk and the output disk, by moving a power roller, the hydraulic control device includes the engine It has an oil pump to be discharged from the discharge port of the sucked oil from the drive to the suction port arrangement, the oil pump, the safety valve to open and close is provided in accordance with the discharge pressure from the discharge port, the oil pump, oil And a second discharge port for discharging oil to a high pressure system or a low pressure system, and a discharge destination of the second discharge port in the oil pump A switching valve for switching between in accordance with the engine operating condition and said low-pressure system and the high-voltage is provided, said safety valve, the first discharge opening and provided on at least one of the second discharge port, characterized in that It is what.

  In the continuously variable transmission according to the present invention, the power roller is tilted by changing the relative position of the power roller with respect to the input disk and the output disk by hydraulic pressure, and the rotational speed ratio between the input disk and the output disk. A cylinder mechanism for changing the input disk, and a pinching mechanism that brings the input disk, the output disk, and the power roller into contact with each other, and exerts a pinching force that sandwiches the power roller between the input disk and the output disk. The hydraulic control device controls the cylinder mechanism and the pinching mechanism with hydraulic pressure from the oil pump.

  In the continuously variable transmission according to the present invention, the safety valve opens when the discharge pressure from the discharge port exceeds a predetermined pressure set in advance, and discharges oil from the discharge port to the suction port or the oil reservoir. It is characterized by.

In the continuously variable transmission according to the present invention , the safety valve is provided in the first discharge port and the second discharge port.

  In the continuously variable transmission according to the present invention, when the safety valve is opened, the oil at the first discharge port is discharged to the second suction port side, and the oil at the second discharge port is discharged to the first suction port side. It is characterized by that.

  In the continuously variable transmission according to the present invention, the oil pump is a gear pump in which three gears mesh in series to transport oil.

  In the continuously variable transmission according to the present invention, the oil pump is fixed so as to cover the pump body, and the suction port and the discharge port are formed. And a pump cover.

According to the continuously variable transmission of the present invention, an oil pump that is driven by an engine and discharges oil sucked from the suction port from the discharge port is provided as a hydraulic control device, and the oil pump is provided according to the discharge pressure from the discharge port. A safety valve that opens and closes is provided. The oil pump is provided with a first discharge port for discharging oil to the high pressure system and a second discharge port for discharging oil to the high pressure system or the low pressure system, and the discharge destination of the second discharge port in the oil pump is set to the engine operating state. Accordingly, a switching valve for switching between the high pressure system and the low pressure system is provided, and a safety valve is provided at at least one of the first discharge port and the second discharge port. Therefore, if the oil discharge pressure at the discharge port rises abnormally, the safety valve opens according to this discharge pressure, and the oil at the discharge port is discharged to the outside, reducing the load on the oil pump and improving durability. can do.

  Embodiments of a continuously variable transmission according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments. In addition, constituent elements in the following embodiments include those that can be easily replaced by those skilled in the art or those that are substantially the same.

  FIG. 1 is a schematic configuration diagram of a hydraulic control device in a toroidal continuously variable transmission according to a first embodiment of the present invention, FIG. 2 is a side view of an oil pump by the hydraulic control device of the first embodiment, and FIG. FIG. 4 is a sectional view taken along the line IV-IV in FIG. 2, FIG. 5 is a sectional view taken along the line V-V in FIG. 2, and FIG. 7 is a schematic cross-sectional view of the step transmission, FIG. 7 is a configuration diagram of a main part of the toroidal continuously variable transmission of the first embodiment, and FIG. 8 is a diagram illustrating a power roller input disk in the toroidal continuously variable transmission of the first embodiment. FIG. 9 is a schematic diagram for explaining the shift position of the power roller with respect to the input disk in the toroidal continuously variable transmission according to the first embodiment. FIG. 10 is a schematic diagram for explaining the toroidal continuously variable transmission according to the first embodiment. Schematic plan view explaining how to put the synchronous wire of the machine It is.

  FIG. 7 is a diagram showing an arbitrary power roller among the power rollers constituting the toroidal-type continuously variable transmission, and an input disk in contact with the power roller. 8 and 9 are views of the input disk as viewed from the output disk side, and only one input disk and one power roller are schematically shown. In the embodiment described below, an internal combustion engine that generates engine torque is used as a drive source that generates a drive force transmitted to the continuously variable transmission of the present invention. A diesel engine, an LPG engine, or the like may be used.

  As shown in FIG. 6, the toroidal continuously variable transmission 1 as the continuously variable transmission according to the first embodiment uses a driving force from an engine 21 as a drive source mounted on the vehicle, that is, an output torque, as the vehicle travels. This is a so-called CVT (CVT: Continuously Variable Transmission) that can be transmitted to the wheel 27 under the optimum conditions according to the state, and can control the gear ratio steplessly (continuously). The toroidal-type continuously variable transmission 1 transmits torque between each input disk 2 and output disk 3 via a power roller 4 sandwiched between the input disk 2 and the output disk 3, and This is a so-called toroidal continuously variable transmission that tilts to change the gear ratio. That is, the toroidal continuously variable transmission 1 includes a power roller 4 having an outer peripheral surface curved between the input disk 2 and the output disk 3 having the toroidal surfaces 2a and 3a and corresponding to the toroidal surfaces 2a and 3a. The torque is transmitted by utilizing the shear force of the oil film of traction oil (traction fluid) formed between the input disk 2, the output disk 3 and the power roller 4.

  Specifically, as shown in FIGS. 6 and 7, the toroidal continuously variable transmission 1 includes an input disk 2, an output disk 3, a power roller 4, and a gear ratio changing unit 5 as a cylinder mechanism. Is provided. The gear ratio changing unit 5 includes a trunnion 6 and a moving unit 7. Further, the moving unit 7 includes a hydraulic piston unit 8 and a hydraulic control device 9. The toroidal continuously variable transmission 1 includes an electronic control unit (ECU) 60 that controls each part of the toroidal continuously variable transmission 1. In this toroidal continuously variable transmission 1, the power roller 4 provided in contact with the input disk 2 and the output disk 3 is moved from the neutral position to the shift position with respect to the input disk 2 and the output disk 3 by the moving unit 7. As a result, the gear ratio, which is the rotational speed ratio between the input disk 2 and the output disk 3, is changed.

  The input disk 2 transmits (inputs) a driving force (torque) from the engine 21 via, for example, a torque converter 22 that is a starting mechanism and a fluid transmission device, a forward / reverse switching mechanism 23, and the like. .

  The engine 21 outputs an engine torque, that is, a driving force for moving forward or backward the vehicle on which the engine 21 is mounted. Further, the engine 21 is electrically connected to the ECU 60, the driving of the engine 21 is controlled by the ECU 60, and the driving force to be output is controlled. The driving force from the engine 21 is transmitted to the torque converter 22 via the crankshaft 21a.

  The torque converter 22 transmits the driving force from the engine 21 to the toroidal continuously variable transmission 1 via the forward / reverse switching mechanism 23. The torque converter 22 includes a pump (pump impeller), a turbine (turbine runner), a stator, and a lockup clutch. The pump is connected to the crankshaft 21a of the engine 21 via a front cover or the like, and is rotatably provided together with the crankshaft 21a and the front cover. The turbine is arranged to face this pump. This turbine is connected to the input shaft 10 via the forward / reverse switching mechanism 23, and is provided so as to be rotatable about the same axis as the crankshaft 21a together with the input shaft 10. The stator is disposed between the pump and the turbine. The lockup clutch is provided between the turbine and the front cover, and is connected to the turbine.

  Therefore, in the torque converter 22, the driving force (engine torque) of the engine 21 is transmitted from the crankshaft 21a to the pump via the front cover. When the lockup clutch is released, the driving force transmitted to the pump is transmitted to the turbine and the input shaft 10 via the hydraulic oil that is a working fluid interposed between the pump and the turbine. The At this time, the torque converter 22 can obtain a predetermined torque characteristic by changing the flow of the working oil circulating between the pump and the turbine by the stator. In the torque converter 22, when the lockup clutch connected to the turbine is engaged with the front cover, the driving force transmitted from the engine 21 to the pump via the front cover does not pass through the hydraulic oil. To the input shaft 10 directly. Here, the engagement / disengagement of the lock-up clutch, that is, ON / OFF control for turning on / off, is performed by hydraulic oil supplied from a hydraulic control device 9 described later. The hydraulic control device 9 is connected to an ECU 60 described later. Therefore, the ON / OFF control of the lockup clutch is performed by the ECU 60.

  The forward / reverse switching mechanism 23 transmits the driving force transmitted from the engine 21 via the torque converter 22 to the input disk 2 of the toroidal continuously variable transmission 1. The forward / reverse switching mechanism 23 includes, for example, a planetary gear mechanism, a friction clutch, a friction brake, and the like, and transmits the driving force of the engine 21 to the input disk 2 directly or reversely. That is, the driving force of the engine 21 via the forward / reverse switching mechanism 23 is a positive rotational driving force that acts in the direction in which the input disk 2 rotates forward (the direction in which the input disk 2 rotates when the vehicle moves forward), or The input disk 2 is transmitted to the input disk 2 as a reverse rotation driving force that acts in the direction in which the input disk 2 rotates in the reverse direction (the direction in which the input disk 2 rotates when the vehicle moves backward). The switching control of the driving force transmission direction by the forward / reverse switching mechanism 23 is performed by executing ON / OFF control for engaging and releasing the friction clutch and the friction brake, that is, ON / OFF. Switching control of the transmission direction of the driving force by the forward / reverse switching mechanism 23, in other words, ON / OFF control of the friction clutch and the friction brake is performed by hydraulic oil supplied from a hydraulic control device 9 described later. Accordingly, switching control of the forward / reverse switching mechanism 23 is performed by the ECU 60.

Two input disks 2 are coupled to an input shaft 10 that is rotated based on the rotation of the engine 21, and is rotatably provided by the input shaft 10. More specifically, each input disk 2 is rotated by a variator shaft 11 that rotates in the same manner as the input shaft 10. Accordingly, each input disk 2 can rotate around the rotation axis X1 of the input shaft 10 as a rotation center. The toroidal type continuously variable transmission 1, with respect to the variator shaft 11, a front side (engine 21 side) front input disk 2 _F is provided, in the direction along the rotation axis X1 in front input disk 2 _F On the other hand, a rear side input disk _2R is provided on the rear side (wheel 27 side) at a predetermined interval.

Front input disk 2 _F is supported on the variator shaft 11 via the ball spline 11a. That is, the front-side input disk 2 _F, together with the rotatable with the rotation of the variator shaft 11 is supported by the movable variator shaft 11 along the rotation axis X1 direction with respect to the variator shaft 11 . In other words Further, the front-side input disk 2 _F, to the variator shaft 11, whereas no relative rotational displacement about the rotational axis X1, in the direction along the rotation axis X1 can be relatively displaced. On the other hand, the rear input disk 2 _R, together are supported by a variator shaft 11 through a spline fitting portion, along the rotation axis X1 by a snap ring 11b provided on the rear end of the variator shaft 11 direction Movement to is restricted. In other words, the rear input disk 2 _R, together with the rotatable with the rotation of the variator shaft 11, is supported movably on the variator shaft 11 along with the movement direction along the rotation axis X1 of the variator shaft 11 Yes. In other words Additionally, rear input disk 2 _R, to the variator shaft 11, with no relative rotational displacement about the rotation axis X1, is not relatively displaced in the direction along the rotation axis X1. In the following description, when it is not necessary to distinguish the front side input disc 2 _F and the rear-side input disk 2 _R, abbreviated as "input disk 2".

  Each input disk 2 is formed with an opening at the center and gradually protruding from the outside toward the center. The slope of the protruding portion of each input disk 2 is formed so that the cross section along the direction of the rotation axis X1 is substantially arc-shaped, and forms a toroidal surface 2a of each input disk 2. The two input disks 2 are provided such that the toroidal surfaces 2a face each other.

The output disks 3 transmit (output) the driving force transmitted (input) to each input disk 2 to the wheel 27 side, and two output disks 3 are provided, one for each input disk 2. The toroidal type continuously variable transmission 1, with respect to the variator shaft 11, the front side output disc 3 _F as the first output disk is provided on the front side (engine 21 side), the rear side (wheel 27 side) rear output disk 3 _R as 2 output disk is provided. A front output disk 3 _F and the rear-side output disc 3 _R is provided between the front input disc 2 _F and the rear-side input disk 2 _R with respect to the direction in which both along the rotation axis X1, More , rear output disk 3 _R is provided between the front side output disc 3 _F and the rear-side input disk 2 _R. That is, the toroidal continuously variable transmission 1 has a front side input disk 2 _F , a front side output disk 3 _F , a rear side output disk 3 _R , and a rear side input in the direction along the rotation axis X 1. It is provided in the order of the disc 2 _R. In the following description, the front side output disc 3 _F and the rear-side output disc 3 when there is no need to distinguish between _R, abbreviated as "the output disc 3 '.

Each input disk 2 and each output disk 3 are provided so as to be rotatable relative to the input shaft 10 coaxially with the rotation axis X1. Accordingly, each output disk 3 can rotate around the rotation axis X1. Each output disk 3 has substantially the same shape as each input disk 2, that is, each output disk 3 has an opening at the center and gradually protrudes from the outside toward the center. The slope of the protruding portion of each output disk 3 is formed such that the cross section along the direction of the rotation axis X1 is substantially arc-shaped, and forms a toroidal surface 3a of each output disk 3. Each output disk 3 is provided between the two input disks 2 in the direction along the rotation axis X1 as described above, and each toroidal surface 3a faces the toroidal surface 2a of each input disk 2. To be provided. That is, in the section along the rotation axis X1, one of the front input disk 2 _F toroidal surface 2a and the front output disk 3 _F toroidal surface 3a and front side facing in (engine 21 side) semicircular cavity forming a C _F, the other of the rear input disk 2 _R toroidal surface 2a and the rear-side output disc 3 _R another rear toroidal surface 3a is opposite of (wheel 27 side) forms a semicircular cavity C _R doing.

  Each output disk 3 is rotatably supported by the variator shaft 11 via a bearing. An output gear 12 is connected between the two output disks 3, and the output gear 12 can rotate together with the two output disks 3. A counter gear 13 is engaged with the output gear 12, and an output shaft 14 is connected to the counter gear 13. Accordingly, the output shaft 14 rotates as each output disk 3 rotates. The output shaft 14 is connected to the wheels 27 via a power transmission mechanism 24, a differential gear 25, etc., and the driving force is transmitted to the wheels 27 via the power transmission mechanism 24, the differential gear 25, etc. (output) )

  The power transmission mechanism 24 transmits driving force between the toroidal-type continuously variable transmission 1 and the differential gear 25. The power transmission mechanism 24 is disposed between the output disk 3 and the differential gear 25. The differential gear 25 transmits driving force between the power transmission mechanism 24 and the wheels 27. The differential gear 25 is disposed between the power transmission mechanism 24 and the wheels 27. A drive shaft 26 is connected to the differential gear 25. Wheels 27 are attached to the drive shaft 26.

  The power roller 4 is provided between the input disk 2 and the output disk 3 in contact with the input disk 2 and the output disk 3, and transmits the driving force from the input disk 2 to the output disk 3. That is, the power roller 4 is formed as a curved contact surface 4a whose outer peripheral surface corresponds to the toroidal surfaces 2a and 3a. The power roller 4 is sandwiched between the input disk 2 and the output disk 3, and the contact surface 4a can contact the toroidal surfaces 2a and 3a. Each power roller 4 is contacted by a trunnion 6 described later. While the surface 4a is in contact with the toroidal surfaces 2a and 3a, the surface 4a is supported rotatably about the rotation axis X2. The power roller 4 is configured to shear an oil film formed between the toroidal surfaces 2a and 3a of the input disk 2 and the output disk 3 and the contact surface 4a of the power roller 4 by traction oil supplied to the toroidal continuously variable transmission 1. The driving force (torque) is transmitted using force.

A total of four power rollers 4 are provided, two for each of the cavities formed by the pair of input disks 2 and output disks 3. That is, the toroidal type continuously variable transmission 1 comprises two power rollers 4 to the front side semicircular cavity C _F is provided with a pair, two power rollers 4 against the rear semicircular cavity C _R pair Is provided.

  More specifically, the power roller 4 includes a power roller main body 41 and an outer ring 42. The power roller main body 41 has the above-described contact surface 4a in contact with the toroidal surfaces 2a and 3a of the input disk 2 and output disk 3 on the outer peripheral surface. The power roller main body 41 is rotatably supported via a radial bearing RB with respect to a rotation shaft 42a formed on the outer ring 42. Further, the power roller main body 41 is rotatably supported on the surface of the outer ring 42 facing the power roller main body 41 via a thrust bearing SB. Accordingly, the power roller main body 41 can rotate around the rotation axis X2 of the rotation shaft 42a.

  The outer ring 42 is formed with an eccentric shaft 42b together with the rotating shaft 42a. The eccentric shaft 42b is formed such that the rotation axis X2 'is shifted from the rotation axis X2 of the rotation shaft 42a. The eccentric shaft 42b is rotatably supported via a radial bearing RB with respect to a fitting portion 6d formed as a recess in a roller support portion 6a of the trunnion 6 described later. Accordingly, the outer ring 42 can rotate around the rotation axis X2 'of the eccentric shaft 42b. That is, the power roller 4 can rotate with respect to the trunnion 6 about the rotation axis X2 and the rotation axis X2 ′, that is, can revolve around the rotation axis X2 ′ and can rotate about the rotation axis X2. Become. As a result, the power roller 4 is configured to be movable in the direction along the rotation axis X1, and for example, it is possible to allow component deformation and variations in component accuracy.

  Here, the input shaft 10 is connected to a hydraulic pressure (end load) mechanism 15 as a clamping mechanism. The hydraulic pressing mechanism 15 brings the input disk 2 and output disk 3 into contact with the power roller 4 and applies a clamping pressure for sandwiching the power roller 4 between the input disk 2 and the output disk 3. The hydraulic pressing mechanism 15 includes a clamping pressure generating hydraulic chamber 15a and a clamping pressure piston 15b.

The clamping pressure generating hydraulic chamber 15a is provided on one side of the two input disks 2 in the direction along the rotation axis X1. Here, squeezing force generating hydraulic chamber 15a is provided on the front side input disc 2 _F side against along the rotation axis X1 direction, it is disposed between the input shaft 10 and the front input disk 2 _F. The hydraulic pressure chamber 15a is supplied with hydraulic oil from the hydraulic control device 9 in accordance with the operating state.

The clamping pressure piston 15b is formed in a disc shape and is provided at one end of the variator shaft 11 so that the center thereof substantially coincides with the rotation axis X1. Nipping and pressing force piston 15b is the end rear input disk 2 _R of the variator shaft 11 is provided opposite end, i.e., are provided on the front side (engine 21 side). Nipping and pressing force piston 15b, to the direction along the rotation axis X1, it is spaced front input disk 2 _F and distance between the input shaft 10 and the front input disk 2 _F. Clamping force generating hydraulic chamber 15a of the above is provided between the nipping and pressing force piston 15b and the front input disk 2 _F.

The clamping pressure piston 15b is rotatable with respect to the variator shaft 11 around the rotation axis X1 together with the variator shaft 11 and is movable in the direction along the rotation axis X1. That is, the clamping pressure piston 15b can be rotated with the rotation of the variator shaft 11, and is supported by the variator shaft 11 so as to be movable with the movement of the variator shaft 11 along the rotation axis X1. Yes. In other words, the clamping pressure piston 15b is not relatively displaced relative to the variator shaft 11 around the rotational axis X1 and is not relatively displaced in the direction along the rotational axis X1. Therefore, the rear side input disk 2 _R , the variator shaft 11 and the pinching pressure piston 15 b are integrally rotatable about the rotation axis X 1 and are movable in the direction along the rotation axis X 1. The front-side input disk 2 _F is rear input disc 2 _R, together with the variator shaft 11 and the nipping and pressing force piston 15b while being rotatable about a rotation axis X1 together, by a ball spline 11a, The rear side input disk 2 _R , the variator shaft 11, and the pressing pressure piston 15 b are relatively movable in the direction along the rotation axis X 1.

Further, the clamping pressure piston 15 b is also connected to the input shaft 10, can be rotated around the rotation axis X <b> 1 together with the input shaft 10, and relatively moves in the direction along the rotation axis X <b> 1. Provided possible. That is, the rear side input disk 2 _R , the variator shaft 11, and the pressing pressure piston 15 b are integrated with the input shaft 10 and can rotate about the rotation axis X 1, while rotating with respect to the input shaft 10. It is relatively movable in the direction along the axis X1. The driving force from the input shaft 10 is transmitted to the variator shaft 11, and is transmitted from the variator shaft 11 to the front side input disk 2 _F and the rear side input disk 2 _R.

Further, the front side input disk 2 _F has a front side input disk clamping pressure application surface 28, while the clamping pressure piston 15 b has a rear side input disk clamping pressure application surface 29. Front input disk nipping and pressing force acting surface 28 at the front side input disc 2 _F, provided on the back of the toroidal surface 2a which is a contact surface between the power roller 4. The rear side input disk clamping pressure operating surface 29 is provided on the surface facing the front side input disk clamping pressure operating surface 28 in the direction along the rotation axis X1 at the clamping pressure piston 15b. The rear side input disk clamping pressure operating surface 29 is provided to face the front side input disk clamping pressure operating surface 28 with the above-described clamping pressure generating hydraulic chamber 15a interposed therebetween. Clamping force generating hydraulic chamber 15a, depending the front input disk nipping and pressing force acting surface 28 and the rear-side input disk nipping and pressing force acting surface 29 between the nipping and pressing force piston 15b and the front input disk 2 _F It is partitioned with respect to the direction along the rotation axis X1. That is, the front-side input disk clamping pressure application surface 28 and the rear-side input disk clamping pressure application surface 29 are arranged such that the front-side input disk clamping pressure application surface 28 enters the clamping pressure generating hydraulic chamber 15a on the rear side. The rear-side input disk clamping pressure operating surface 29 faces the clamping pressure generating hydraulic chamber 15a on the front side.

Accordingly, the hydraulic pressing mechanism 15, clamping force generating hydraulic chamber hydraulic oil supplied to the 15a (traction oil) front input disk nipping and pressing force acting surface 28 hydraulic by the front input disk 2 _F in and nipping and pressing by the action of nipping and pressing force to the rear input disk nipping and pressing force acting surface 29 of the pressure piston 15b, moving the front input disk 2 _F from the hydraulic pressing mechanism 15 side in a direction away to the rear side, rear moving the side input disc 2 _R together with the variator shaft 11 in a direction approaching from the rear side to the hydraulic pressing mechanism 15 side. At this time, the front-side input disk 2 _F moves relative to the variator shaft 11 in the direction along the rotation axis X1. The hydraulic pressing mechanism 15, the front-side input disk 2 _F is moved from the hydraulic pressing mechanism 15 side to the rear side, by moving the rear input disk 2 _R direction toward the front side along with the variator shaft 11, The front side input disc 2 _F is brought closer to the front side output disc 3 _F side, and the rear side input disc 2 _R is brought closer to the rear side output disc 3 _R side, and the front side input disc 2 _F and the front side output disc 3 _F are generating a clamping force between and between the rear input disk 2 _R and the rear side output disc 3 _R a. Thus, the hydraulic pressing mechanism 15, since to generate a clamping pressure between and between the rear input disk 2 _R and the rear side output disc 3 _R between the front input disc 2 _F and the front output disk 3 _F , between the front-side input disk 2 _F and the front output disk 3 _F at a predetermined clamping pressure power rollers 4, respectively, can be sandwiched between the rear-side input disk 2 _R and the rear side output disc 3 _R . As a result, it is possible to prevent slipping between the input disk 2, the output disk 3 and the power roller 4 and maintain the traction state.

  Here, the pressing pressure by the hydraulic pressing mechanism 15 is applied to the toroidal continuously variable transmission 1 by controlling the amount of hydraulic oil supplied to the clamping pressure generating hydraulic chamber 15a by a hydraulic control device 9 described later. Is controlled to a predetermined magnitude based on the input torque. The hydraulic control device 9 is connected to an ECU 60 described later. Therefore, the ECU 60 controls the magnitude of the pressing pressure by the hydraulic pressing mechanism 15.

  As described above, the gear ratio changing unit 5 includes the trunnion 6 and the moving unit 7. The moving unit 7 moves the power roller 4 together with the trunnion 6 with respect to the rotation axis X 1 of the input disk 2 and the output disk 3. The gear ratio is changed by moving and tilting the power roller 4 with respect to the input disk 2 and the output disk 3. Here, the transmission gear ratio is the rotation speed ratio between the input disk 2 and the output disk 3, and typically represented by [transmission ratio = output-side contact radius (contact radius where the power roller 4 and the output disk 3 are in contact with each other). (Distance between the contact point and the rotation axis X1) / input side contact radius (contact radius where the input disk 2 and the power roller 4 are in contact)].

  Specifically, each trunnion 6 rotatably supports the power roller 4 and moves the power roller 4 with respect to the input disk 2 and the output disk 3 to tilt with respect to the input disk 2 and the output disk 3. It supports to roll freely. The trunnion 6 has a roller support portion 6a and a swing shaft 6b. The roller support portion 6a has a space portion 6c in which the power roller 4 is disposed, and a recessed fitting portion 6d is formed in the space portion 6c. The trunnion 6 rotatably supports the power roller 4 by inserting the eccentric shaft 42b of the power roller 4 into the fitting portion 6d as described above in the space 6c. Further, the roller support portion 6a is provided so as to be movable integrally with the swing shaft 6b. The oscillating shaft 6b is formed in a columnar shape so as to be rotatable about the rotation axis X3. Therefore, the trunnion 6 is supported by a casing (not shown) via the lower link 16 and the upper link 17 so that the roller support portion 6a can rotate about the rotation axis X3 together with the swing shaft 6b. The trunnion 6 is supported by a casing (not shown) via a lower link 16 and an upper link 17 so as to be movable in a direction along the rotation axis X3, and is moved along the rotation axis X3 by a moving unit 7 described later. It can be moved in any direction.

Four trunnions 6 are provided in total, two for each of the cavities formed by the pair of input disks 2 and output disks 3, and each support four power rollers 4 one by one. That is, the toroidal type continuously variable transmission 1 comprises two trunnions 6 supporting each two power rollers 4 to the front side semicircular cavity C _F is provided with a pair, on the rear side semicircular cavity C _R On the other hand, two trunnions 6 that support the two power rollers 4 are provided as a pair.

  Here, the trunnion 6 supports the power roller 4 so that the rotation axis X2 of the power roller 4 is parallel to a plane perpendicular to the rotation axis X3 of the swing shaft 6b. The trunnion 6 is arranged so that the rotation axis X3 of the swing shaft 6b is parallel to a plane perpendicular to the rotation axis X1 of the input disk 2 and the output disk 3. That is, the trunnion 6 moves along the rotation axis X3 in a plane perpendicular to the rotation axis X1 so that the power roller 4 moves along the rotation axis X3 with respect to the rotation axis X1 of the input disk 2 and the output disk 3. Can be moved. Further, the trunnion 6 rotates and swings about the rotation axis X3, so that the power roller 4 can be moved with respect to the input disk 2 and the output disk 3 about the rotation axis X3 in a plane perpendicular to the rotation axis X3. It can be tilted freely. In other words, the trunnion 6 supports the power roller 4 so that the power roller 4 can be tilted when a tilting force described later acts on the power roller 4.

  The moving unit 7 moves the power roller 4 together with the trunnion 6 in the direction along the rotation axis X3, and includes the hydraulic piston unit 8 and the hydraulic control device 9 as described above.

  The hydraulic piston portion 8 includes a transmission control piston 81 and a transmission control hydraulic chamber 82, and receives the hydraulic pressure of the hydraulic oil introduced into the transmission control hydraulic chamber 82 by the flange portion 84 of the transmission control piston 81. Thus, the trunnion 6 is moved in two directions (A1 direction and A2 direction) along the rotation axis X3. In other words, the hydraulic piston portion 8 applies a shift control pressing force to the flange portion 84 provided in the trunnion 6 by the hydraulic pressure of the hydraulic oil supplied to the shift control hydraulic chamber 82.

  Specifically, the transmission control piston 81 includes a piston base 83 and a flange portion 84. The piston base 83 is formed in a cylindrical shape, is inserted into one end of the swing shaft 6b, and is fixed with respect to the direction of the rotational axis X3 and the direction around the rotational axis X3.

  The flange portion 84 is fixedly provided so as to protrude from the piston base 83 in the radial direction of the piston base 83, in other words, in the radial direction of the swing shaft 6b, and the swing shaft 6b of the piston base 83 and the trunnion 6 is provided. At the same time, it can move in the direction along the rotation axis X3. The flange portion 84 is formed in an annular plate shape around the rotation axis X3 of the swing shaft 6b.

  The shift control hydraulic chamber 82 is configured by a hydraulic chamber constituent member 85. The hydraulic chamber constituent member 85 includes a cylinder body 86 as a first constituent member and a lower cover 87 as a second constituent member. That is, the hydraulic chamber constituting member 85 forms the wall surface of the transmission control hydraulic chamber 82 and is divided into the cylinder body 86 and the lower cover 87 with respect to the direction along the rotation axis X3 that is the movement direction (stroke direction) of the trunnion 6. Has been. The cylinder body 86 is formed with a recess serving as a space of the transmission control hydraulic chamber 82. The lower cover 87 is fixed to the cylinder body 86 so as to close the opening of the concave portion of the cylinder body 86, whereby the transmission control hydraulic chamber 82 is formed in a cylindrical shape centered on the rotation axis X3 by the cylinder body 86 and the lower cover 87. Comparted into a cylinder. The cylinder body 86 and the lower cover 87 are fixed to a casing (not shown) on the opposite side of the cylinder body 86 from the lower cover 87 side.

  The flange portion 84 is accommodated in the transmission control hydraulic chamber 82 into which hydraulic oil is introduced, and two hydraulic chambers, that is, the first hydraulic chambers in the direction along the rotation axis X3 in the transmission control hydraulic chamber 82 are provided. The partition is divided into a hydraulic chamber OP1 and a second hydraulic chamber OP2. The first hydraulic chamber OP1 moves the trunnion 6 together with the flange portion 84 in the first direction A1 along the rotation axis X3 by the hydraulic pressure of the hydraulic oil supplied to the inside, while the second hydraulic chamber OP2 is supplied to the inside. The trunnion 6 together with the flange 84 is moved in the second direction A2, which is the reverse direction of the first direction, by the hydraulic pressure of the hydraulic oil. An annular seal member S is provided at the distal end portion on the radially outer side of the flange portion 84. Accordingly, the first hydraulic chamber OP1 and the second hydraulic chamber of the shift control hydraulic chamber 82 defined by the flange portion 84. The OP2 is sealed by the seal member S so that the hydraulic oil does not leak from each other.

  Since each of the pair of input disks 2 and output disks 3 is provided with two power rollers 4 and trunnions 6, the first hydraulic chamber OP1 and the second hydraulic chamber OP2 have a pair of input disks 2 and output disks. Two for every three will be provided. At this time, in the pair of trunnions 6, the positional relationship between the first hydraulic chamber OP1 and the second hydraulic chamber OP2 is switched for each trunnion 6. That is, the hydraulic chamber that is the first hydraulic chamber OP1 of one trunnion 6 is the second hydraulic chamber OP2 of the other trunnion 6, and the hydraulic chamber that is the second hydraulic chamber OP2 of one trunnion 6 is the second hydraulic chamber OP2 of the other trunnion 6. 1 hydraulic chamber OP1. Therefore, in the toroidal-type continuously variable transmission 1 shown in FIG. 7, the two power rollers 4 provided for each of the pair of input disks 2 and output disks 3 are driven by the hydraulic pressure in the first hydraulic chamber OP1 or the second hydraulic chamber OP2. , And move in opposite directions along the rotation axis X3.

  The hydraulic control device 9 supplies hydraulic oil to each part of the transmission, for example, the hydraulic pressing mechanism 15, the torque converter 22, the forward / reverse switching mechanism 23, and the hydraulic pressure of the hydraulic oil in the transmission control hydraulic chamber 82. Is to control. The hydraulic control device 9 sucks, pressurizes, and discharges the hydraulic oil stored in the oil pan and supplied to each part of the transmission with an oil pump. The hydraulic control device 9 supplies hydraulic oil pressurized by an oil pump to a flow rate control valve or the like via a pressure regulator valve. The flow rate control valve includes a spool valve element, an electromagnetic solenoid, and the like, and supplies hydraulic oil to the first hydraulic chamber OP1 and the second hydraulic chamber OP2, or from the first hydraulic chamber OP1 and the second hydraulic chamber OP2. It controls the discharge of hydraulic oil. The flow rate control valve of the hydraulic control device 9 is configured such that an electromagnetic solenoid driven by a drive current based on a control command value input from the ECU 60 displaces the position of the spool valve element, whereby the first hydraulic chamber OP1 and the second hydraulic pressure The flow rate of the hydraulic oil supplied to and discharged from the chamber OP2 is controlled. In addition, this pressure regulator valve removes the hydraulic oil on the downstream side when the hydraulic pressure on the downstream side of the pressure regulator valve exceeds a predetermined hydraulic pressure, that is, the line pressure used as the original pressure of the hydraulic control device 9. The pressure is returned to the oil pan and adjusted to a predetermined line pressure.

  For example, the ECU 60 controls the flow rate control valve of the hydraulic control device 9, supplies the hydraulic oil pressurized by the oil pump to the first hydraulic chamber OP1, and discharges the hydraulic oil in the second hydraulic chamber OP2. The hydraulic pressure in the first hydraulic chamber OP1 acts on the flange portion 84, so that [the hydraulic pressure in the first hydraulic chamber OP1> the hydraulic pressure in the second hydraulic chamber OP2]. Thereby, the flange part 84 of the hydraulic piston part 8 is pressed in the first direction A1 along the rotation axis X3, and the power roller 4 moves together with the trunnion 6 in the first direction A1 along the rotation axis X3. Similarly, when the ECU 60 controls the flow control valve of the hydraulic control device 9 to discharge the hydraulic oil pressurized by the oil pump from the first hydraulic chamber OP1 and supply it into the second hydraulic chamber OP2, the second hydraulic pressure is obtained. The hydraulic pressure in the chamber OP2 acts on the flange portion 84, so that [the hydraulic pressure in the first hydraulic chamber OP1 <the hydraulic pressure in the second hydraulic chamber OP2]. Thereby, the flange part 84 of the hydraulic piston part 8 is pressed in the second direction A2 along the rotation axis X3, and the power roller 4 moves in the second direction A2 along the rotation axis X3 together with the trunnion 6. At this time, the movement of the power roller 4 in the first direction A1 or the second direction A2 is adjusted according to the amount of movement of the spool valve element of the flow control valve.

  Therefore, the moving unit 7 is driven by the ECU 60 by the hydraulic control device 9 to control the hydraulic pressure in each of the shift control hydraulic chambers 82 of the hydraulic piston unit 8, so that a predetermined shift is applied to the flange portion 84 of the shift control piston 81. By applying a control pressing force, the power roller 4 together with the trunnion 6 can be moved in two directions along the rotation axis X3, that is, in the first direction A1 and the second direction A2. The speed change ratio changing unit 5 moves the power roller 4 together with the trunnion 6 together with the trunnion 6 from the neutral position (see FIG. 8) with respect to the input disk 2 and the output disk 3 (see FIG. 9). The gear ratio can be changed by tilting the power roller 4 with respect to the input disk 2 and the output disk 3.

  Here, as shown in FIG. 8, the neutral position of the power roller 4 with respect to the input disk 2 and the output disk 3 is a position where the gear ratio is fixed, and the power roller 4 is positioned with respect to the input disk 2 and the output disk 3. In this position, the tilting force to be tilted cannot act on the power roller 4. That is, when the power roller 4 is in the neutral position and the transmission gear ratio is fixed, the rotation axis X2 of the power roller 4 is set in a plane that includes the rotation axis X1 and that is perpendicular to the rotation axis X3. Is done. In other words, at the neutral position of the power roller 4 (when the transmission ratio is fixed), the position of the power roller 4 in the direction along the rotational axis X3 is such that the rotational axis X2 of the power roller 4 passes through the rotational axis X1 (orthogonal). Set to position. At this time, the rotation direction (rolling direction) of the power roller 4 and the rotation direction of the input disk 2 coincide with each other at the contact point between the power roller 4 and the input disk 2. Therefore, the power roller 4 continues to rotate together with the input disk 2 while remaining in the neutral position, and the gear ratio during this period is fixed.

  At this time, since the force acting on the power roller 4 from the input disk 2 is only the driving force (torque), the hydraulic piston portion 8 of the moving portion 7 and the hydraulic control device 9 only resist this driving force by the hydraulic pressure. Is applied to the trunnion 6. That is, when the power roller 4 and the trunnion 6 supporting the power roller 4 are in the neutral position, as described above, the tangential force F1 acting on the contact point between the input disk 2 and the output disk 3 and the power roller 4 according to the input torque. A shift control pressing force F2 (see FIG. 8) having a magnitude that opposes (see FIG. 8) is applied to the flange portion 84, and the tangential force F1 acting on the power roller 4 and the shift control pressing force F2 are balanced. The positions of the power roller 4 and the trunnion 6 that supports the power roller 4 are fixed to the neutral position, and the gear ratio is fixed.

  On the other hand, as shown in FIG. 9, the speed change position of the power roller 4 is a position where the speed ratio is changed, and the tilting force that tilts the power roller 4 with respect to the input disk 2 and the output disk 3 is this power. It is a position that acts on the roller 4. That is, when the power roller 4 is in the speed change position and the speed ratio is changed, the rotation axis X2 of the power roller 4 is a plane including the rotation axis X1 and the rotation axis from the plane perpendicular to the rotation axis X3. It is set at a position moved in the first direction A1 or the second direction A2 along X3. In other words, at the speed change position of the power roller 4 (during speed change), the position of the power roller 4 in the direction along the rotation axis X3 is the position where the rotation axis X2 of the power roller 4 passes the rotation axis X1, that is, the neutral position. Is set to a position offset from. At this time, at the contact point between the power roller 4 and the input disk 2, the rotation direction of the power roller 4 is shifted from the rotation direction of the input disk 2, whereby a tilting force acts on the power roller 4. As a result, a side slip occurs between the power roller 4 and the input disk 2 and the output disk 3 due to the tilting force acting on the power roller 4, and the power roller 4 tilts with respect to the input disk 2 and the output disk 3. As a result, the input side contact radius between the power roller 4 and the input disk 2 and the output side contact radius between the power roller 4 and the output disk 3 are changed, and accordingly, the gear ratio is changed.

  For example, as shown in FIG. 9, when the input disk 2 is rotating in the direction of arrow B (counterclockwise) in FIG. 9, the power roller 4 is moved in the second direction A2 (power roller along the rotation axis X3). 4 is offset in the direction opposite to the direction of movement of the input disk 2 at the contact point between the input disk 2 and the direction opposite to the direction of rotation of the input disk 2 (direction along the direction of rotation of the output disk 3). Then, the force in the circumferential direction of the input disk 2 acts on the power roller 4 at the contact point between the power roller 4 and the input disk 2, and the power roller 4 is moved to the peripheral side of the input disk 2 (power roller 4 Tilting force acts in the direction of separating the input disk 2 from the rotation axis X1. As a result, the power roller 4 moves so that the contact point with the input disk 2 moves radially outward of the input disk 2 and the contact point with the output disk 3 moves radially inward of the output disk 3. The gear ratio is changed to the decreasing side and upshifted. Then, the changed gear ratio is fixed by returning the power roller 4 to the neutral position again.

  Conversely, when downshifting, the power roller 4 is moved in the first direction A1 along the rotation axis X3 (the moving direction of the input disk 2 at the contact point between the power roller 4 and the input disk 2, that is, the rotation of the input disk 2). In the direction along the direction (the direction opposite to the rotation direction of the output disk 3)). Then, the force in the circumferential direction of the input disk 2 acts on the power roller 4 at the contact point between the power roller 4 and the input disk 2, and the power roller 4 moves to the center side of the input disk 2 (power roller 4 Is applied to the rotation axis X1 of the input disk 2). As a result, the power roller 4 moves so that the contact point with the input disk 2 moves radially inward of the input disk 2 and the contact point with the output disk 3 moves radially outward of the output disk 3. The gear ratio is changed to the increasing side and downshifted. Then, the changed gear ratio is fixed by returning the power roller 4 to the neutral position again.

  Here, the position of the power roller 4 is determined by the stroke amount from the neutral position and the tilt angle with respect to the input disk 2 and the output disk 3. The stroke amount of the power roller 4 is set from the neutral position to the first direction A1 or the second direction A2 with a neutral position where the rotation axis X2 of the power roller 4 passes through the rotation axis X1 of the input disk 2 and the output disk 3 as a reference position. The amount of movement (the amount of offset from the neutral position). The tilt angle of the power roller 4 is input from this reference position with the position where the rotation axis X2 which is the rotation center of the power roller 4 is orthogonal to the rotation axis X1 which is the rotation center of the input disk 2 and the output disk 3 as a reference position. The tilt angle (acute angle on the acute angle side) with respect to the disk 2 and the output disk 3, in other words, the rotation angle around the rotation axis X3. The transmission ratio of the toroidal-type continuously variable transmission 1 is determined by the tilt angle of the power roller 4 with respect to the input disk 2 and the output disk 3, and this tilt angle is the amount of stroke from the neutral position of the power roller 4. Determined by the integral value.

  Here, the ECU 60 controls the driving of each part of the toroidal-type continuously variable transmission 1 according to the operating state of the toroidal-type continuously variable transmission 1, and the actual gear ratio that is the actual gear ratio of the toroidal-type continuously variable transmission 1. Is to control. That is, the ECU 60, for example, the engine speed, the throttle opening, the accelerator opening, the engine speed, the input disk speed, the output shaft speed, the shift position and the like detected by various sensors, Based on the stroke amount, etc., a target gear ratio that is a target gear ratio is determined and the gear ratio changing unit 5 is driven to move the power roller 4 from the neutral position to the gear shift position side to a predetermined stroke amount. The gear ratio is changed by tilting to a tilt angle of. Furthermore, the ECU 60 performs duty control on the drive current supplied to the flow rate control valve of the hydraulic control device 9 based on the control command value, so that the first hydraulic chamber OP1 and the second hydraulic chamber OP2 of the hydraulic piston portion 8 are controlled. By controlling the hydraulic pressure and moving the power roller 4 together with the trunnion 6 from the neutral position to the shift position to a predetermined stroke amount and tilting to a predetermined tilt angle, the actual gear ratio becomes the target gear ratio. To control.

  When the driving force (torque) is input to the input disk 2, the toroidal continuously variable transmission 1 as described above transmits the driving force to the power roller 4 that is in contact with the input disk 2 via traction oil. Further, the driving force is transmitted from the power roller 4 to the output disk 3 via traction oil. During this time, the traction oil is changed to glass by being pressurized, and the driving force is transmitted by the accompanying large shearing force, so that each of the input disks 2 and output disks 3 has a clamping force corresponding to the input torque with the power roller 4. It is pressed by the hydraulic pressing mechanism 15 so as to occur between the two. Further, the peripheral speed of the power roller 4 and the peripheral speed at the torque transmission point of each input disk 2 and output disk 3 (contact point where the power roller 4 is in contact via the traction oil) are substantially the same. Depending on the radius from the rotation axis X1 of the contact point between the input disk 2 and the power roller 4 and the radius from the rotation axis X1 of the contact point between the power roller 4 and the output disk 3, each input disk 2, output The rotational speed (rotational speed) of the disk 3 is different, and the ratio of the rotational speed (rotational speed) becomes the transmission ratio.

  Then, when changing the gear ratio to the set target gear ratio, that is, when the gear ratio is changed, the ECU 60 applies a drive current to the flow control valve of the hydraulic control device 9 based on the rotation direction of the input disk 2. By supplying and controlling the hydraulic pressures of the first hydraulic chamber OP1 and the second hydraulic chamber OP2, the trunnion 6 is moved from the neutral position to the first direction A1 or until the power roller 4 has an inclination angle corresponding to the target gear ratio. Move in the second direction A2. For example, in a state where the input disk 2 is rotating in the direction of arrow B (counterclockwise) in FIG. 7, the power roller 4 is moved from the neutral position to the first direction along the rotation axis X3 by the hydraulic pressure of the first hydraulic chamber OP1. When moved to A1, as described above, the gear ratio increases and a downshift is performed. On the other hand, in a state where the input disk 2 is rotating in the direction of arrow B (counterclockwise) in FIG. 7, the power roller 4 is moved from the neutral position to the second direction along the rotation axis X3 by the hydraulic pressure of the second hydraulic chamber OP2. When moved to A2, as described above, the gear ratio is reduced and an upshift is performed. When the set transmission gear ratio is fixed, the trunnion 6 is moved in the first direction A1 or the second direction A2 until the power roller 4 reaches the neutral position again.

  The ECU 60 determines the actual gear ratio (actual gear ratio) based on the tilt angle of the power roller 4 detected by the tilt angle sensor (not shown) and the stroke amount detected by the stroke sensor (not shown). ) Is the target feedback ratio (target transmission ratio after the shift). That is, the ECU 60 determines a target tilt angle, which is a target tilt angle corresponding to the target gear ratio, based on the accelerator opening and the vehicle speed, and detects the actual tilt detected by the target tilt angle and the tilt angle sensor. Based on the deviation from the actual tilt angle, which is the tilt angle, the target speed ratio and the target stroke amount that is the target stroke amount corresponding to the target tilt angle are determined, and the stroke amount detected by the stroke sensor is the target stroke amount. The hydraulic control device 9 of the moving unit 7 is controlled so that the stroke amount is obtained. In such shift control of the toroidal-type continuously variable transmission 1, basically, only the tilt angle (in other words, the gear ratio) detected by the tilt angle sensor needs to be feedback-controlled, but the stroke amount is Since this corresponds to the differentiation of the tilt angle, the damping effect for suppressing the vibration in the tilt control can be obtained by performing the feedback control of the stroke amount detected by the stroke sensor. Further, the ECU 60 may perform feed-forward control together with this feedback control in order to improve the response of the gear ratio.

  Here, as shown in FIG. 7, the toroidal-type continuously variable transmission 1 has two power rollers 4 provided for each of the pair of input disks 2 and output disks 3, and a reverse direction along the rotation axis X3 of the trunnion 6. As a mechanism for synchronizing the movement, a link mechanism including a lower link 16 and an upper link 17 is provided. The lower link 16 connects the pair of trunnions 6 via a radial bearing RB on one end side (between the cylinder body 86 and the roller support portion 6a) where the speed change control piston 81 is provided on the swing shaft 6b. On the other hand, the upper link 17 connects the pair of trunnions 6 via the radial bearing RB on the other end side of the swing shaft 6b. The lower link 16 and the upper link 17 are respectively supported by lower post and upper post support shafts 16a and 17a fixed to a casing (not shown). The support shafts 16a and 17a are extended in a direction parallel to the rotation axis X1, and the lower link 16 and the upper link 17 are configured to be swingable in a seesaw shape with the support shafts 16a and 17a as fulcrums. Yes. Therefore, the lower link 16 and the upper link 17 can synchronize the movement of the pair of trunnions 6 in the reverse direction along the rotation axis X3.

  Further, as shown in FIGS. 7 and 10, the toroidal continuously variable transmission 1 has a synchronization mechanism 18 as a synchronization means as a mechanism for promoting the synchronization of rotation about the rotation axis X 3 of the plurality of trunnions 6. Is provided. The synchronization mechanism 18 includes a synchronization wire 19 as a rotational force transmission material and a fixed pulley 20 as a winding portion.

  The fixed pulley 20 is fixed to each swing shaft 6b of each trunnion 6. The plurality of fixed pulleys 20 are provided on the lower side in FIG. 7 of the piston base 83 (the side opposite to the side on which the power roller 4 is disposed) in each swing shaft 6b. The fixed pulley 20 is formed in a columnar shape, and is fixed to the swing shaft 6b so that the center axis substantially coincides with the rotation axis X3.

  The fixed pulley 20 is provided so as not to rotate around the rotation axis X3 with respect to the swing shaft 6b and to be unable to move in the direction along the rotation axis X3. That is, each fixed pulley 20 is not relatively displaced about the rotation axis X3 relative to each swing shaft 6b of each trunnion 6, and is not relatively displaced in the direction along the rotation axis X3. Accordingly, each fixed pulley 20 can be rotated along with the rotation about the rotation axis X3 of each swing shaft 6b of each trunnion 6, and can be moved along with the movement along the rotation axis X3. Each of the fixed pulleys 20 is wound with the synchronous wire 19 via a caulking member 31 as a stopper.

  The synchronization wire 19 transmits a rotational force (rotational torque) for rotating one trunnion 6 around the rotation axis X3 to the other trunnions 6. That is, the synchronization wire 19 transmits the rotational force around the rotation axis X <b> 3 that acts on one trunnion 6 to the other trunnions 6 by the tilt of the power roller 4. In the toroidal continuously variable transmission 1, the rotational directions around the rotation axis X <b> 3 are mutually changed when the transmission ratio is changed by the transmission ratio changing unit 5 with respect to the four fixed pulleys 20 provided in the four trunnions 6. A total of four synchronization wires 19 are provided, one each between a pair of trunnions 6 in the opposite direction. Each synchronization wire 19 is reversed and stretched so as to intersect once between the fixed pulleys 20. Each synchronization wire 19 has a metal arcuate tube-shaped caulking member 31 that is caulked at its end or the like so that the planar shape is an endless loop shape with an eight shape. Here, “caulking” refers to, for example, the entire process of tightening and fixing by applying a pressing force to cause plastic deformation.

  In the toroidal-type continuously variable transmission 1, when the power roller 4 is tilted to change the transmission gear ratio, the rotational direction around the rotation axis X3 of each trunnion 6 is set to one trunnion 6 on the front side (for example, The rotation direction of the trunnion 6 on the lower side in FIG. 6 and the other trunnion 6 on the rear side (for example, the upper trunnion in FIG. 6) are the same direction, and the other trunnion 6 on the front side (for example, the upper trunnion in FIG. 6). ) And one trunnion 6 on the rear side (for example, the lower trunnion in FIG. 6) are in the same direction.

  Therefore, the synchronization mechanism 18 is configured to rotate the rotational force of one trunnion 6 whose rotational directions around the rotational axis X3 are opposite to each other when changing the gear ratio due to the frictional force between each fixed pulley 20 and each synchronous wire 19. (Rotational torque) can be transmitted to the other trunnion 6, and the rotations of the four trunnions 6 can be synchronized with each other via the respective synchronization wires 19. Accordingly, the tilting operations of the four power rollers 4 are synchronized with each other, and the tilt angles of the power rollers 4 with respect to the input disk 2 and the output disk 3 are the same among the plurality of power rollers 4. It can be.

  As a result, in the tilting operation (transmission operation) of each power roller 4 and each trunnion 6, due to variations in the member accuracy and assembly accuracy of the trunnion 6 that is the support structure of the plurality of power rollers 4, the plurality of power rollers 4 Even when the clamping pressure of the hydraulic pressure pressing mechanism 15 does not act evenly, or even when a slight shift is likely to occur in the shift response due to the difference in the oil path resistance of the hydraulic control device 9, the synchronization mechanism 18 Since the rotations of the plurality of trunnions 6 are synchronized with each other and the tilting operations of the plurality of power rollers 4 can be synchronized with each other, the shift control accuracy of the toroidal continuously variable transmission 1 can be improved.

  In the above description, the synchronization wire 19 is caused to intersect once between the trunnions 6 whose rotational directions around the rotation axis X3 are opposite to each other when the transmission ratio is changed by the transmission ratio changing unit 5. However, the present invention is not limited to this, and the rotation of the plurality of trunnions 6 can be synchronized with each other via the synchronization wire 19 as long as it intersects an odd number of times (for example, three times). Can be made. Further, when the transmission gear ratio is changed by the transmission gear ratio changing section 5, the synchronization wire 19 does not intersect between the trunnions 6 whose rotation directions around the rotation axis X3 are the same direction. Similarly, the rotation of the plurality of trunnions 6 can also be synchronized with each other by winding them around the fixed pulleys 20 evenly (for example, intersecting twice).

  By the way, in such a toroidal continuously variable transmission 1, the hydraulic control device 9 supplies traction oil to the torque converter 22, the forward / reverse switching mechanism 23, the gear ratio changing unit 5, the hydraulic pressure mechanism 15, and the like. The oil pump is driven in synchronization with the engine. Further, this traction oil has a high viscosity and has a property of further increasing the viscosity at low temperatures. For this reason, when the engine 21 is cold started, the oil pump sucks and discharges highly viscous traction oil, which requires an excessive driving torque and may cause a start failure of the engine 21. At the same time, the load on the oil pump increases.

  Therefore, in the toroidal continuously variable transmission 1 according to the first embodiment, as shown in FIG. 1, an oil pump 105 having two suction ports 101 and 102 and two discharge ports 103 and 104 is provided. A safety valve 106 that opens and closes according to the discharge pressure from the second discharge port 104 is provided. When the oil temperature is low and the viscosity is high, such as when the engine 21 is cold started, the discharge pressure from the second discharge port 104 is increased. Accordingly, the safety valve 106 is opened to reduce the driving torque of the oil pump 105 to prevent the engine 21 from starting poorly, and to suppress an abnormal pressure rise in the oil pump 105 to reduce the load and to be durable. Improved.

  That is, in the hydraulic control device 9, traction oil as hydraulic oil is stored in the oil pan (oil storage unit) 107. The oil pump 105 is driven in synchronism with the rotation of the crankshaft 21a of the engine 21 and can discharge the sucked oil after boosting. As will be described later, the oil pump 105 is a gear pump that transports oil by meshing three gears in series and rotating the gears synchronously. In this case, the oil pump 105 has the first suction port 101 and the second suction port 102, and also has the first discharge port 103 and the second discharge port 104, and the discharge capacity from the first discharge port 103 is The discharge capacity from the second discharge port 104 is set to be smaller.

  In the oil pump 105, the first suction passage 108 is connected to the first suction port 101, and the first suction passage 108 communicates with the oil pan 107 through the filter 109. Further, a first discharge passage 110 is connected to the first discharge port 103 by the oil pump 105, and the first discharge passage 110 communicates with a control system A as a high-pressure system.

  In addition, the second suction passage 111 is connected to the second suction port 102 by the oil pump 105, and the second suction passage 111 is connected to the first suction passage 108. Further, the second discharge passage 112 is connected to the second discharge port 104 by the oil pump 105, and the second discharge passage 112 is connected to the third discharge passage 114 and the fourth discharge passage 115 via the switching valve 113. Has been. The switching valve 113 is an electromagnetic valve, and can switch the switching destination of the second discharge passage 112 between the third discharge passage 114 and the fourth discharge passage 115. The third discharge passage 114 communicates with the control system A via the first discharge passage 110, and the fourth discharge passage 115 is connected to the lubrication system B.

  In this case, the control system A is a so-called line pressure system, and includes the speed ratio changing unit 5 and the hydraulic pressure pressing mechanism 15 described above. That is, the line pressure system is provided with a flow rate control valve that adjusts the hydraulic pressure to the transmission control hydraulic chamber 82 in the transmission ratio changing unit 5, and adjusts the hydraulic pressure to the clamping pressure generating hydraulic chamber 15 a in the hydraulic pressing mechanism 15. A pressure control valve is provided. Further, the lubrication system B has at least a sliding portion of the toroidal continuously variable transmission 1. The first discharge passage 110 and the second discharge passage 112 are connected by a connection passage 116, and oil flow from the first discharge passage 110 to the second discharge passage 112 is prohibited in the connection passage 116. A check valve 117 is provided.

  The oil pump 105 is provided with a safety valve 106 that opens and closes according to the discharge pressure from the second discharge port 104. The safety valve 106 opens when the discharge pressure from the second discharge port 104 exceeds a predetermined pressure set in advance, and discharges oil from the second discharge port 104 to the first suction port 101 (or the oil pan 107). be able to.

  Here, the oil pump 105 of the first embodiment will be described in detail.

  In the oil pump 105, as shown in FIGS. 2 to 5, the casing 121 has a first pump cover 123 and a second pump cover 124 fixed by a plurality of bolts 125 so as to cover both sides of the pump body 122. Being done. The casing 121 is rotatably accommodated with three gears 126a, 126b, 126c meshing in series with each other, and is fixed to the transmission housing 127.

  The pump body 122 is formed with a long hole 122a at the center, and is rotatably supported by the rotary shafts 128a, 128b, and 128c in a state where the three gears 126a, 126b, and 126c are engaged in the long hole 122a. . In this case, the rotating shaft 128b is driven by the engine 21. The elongated hole 122a of the pump body 122 has a first suction recess 129a and a first discharge recess 130a corresponding to the gear 126a, and a second suction recess 129b and a second discharge corresponding to the gear 126c. A recess 130b is formed.

  A first suction port 101 is formed through the pump body 122 and the first pump cover 123, and a first suction groove that communicates the first suction port 101 and the first suction recess 129 a with the first pump cover 123. 131a is formed. A first discharge port 103 is formed through the first pump cover 123, and a first discharge groove 132 a that communicates the first discharge port 103 and the first discharge recess 130 a is formed in the first pump cover 123. Is formed.

  A second suction port 102 is formed through the pump body 122 and the first pump cover 123, and a second suction groove communicating with the first pump cover 123 through the second suction port 102 and the second suction recess 129 b. 131b is formed. A second discharge port 104 is formed through the first pump cover 123, and a second discharge groove 132b communicating with the second pump port 104 and the second discharge recess 130b is formed in the first pump cover 123. Is formed.

  The first pump cover 123 has a mounting hole 123a, and the safety valve 106 is mounted in the mounting hole 123a. That is, the first pump cover 123 is formed with a suction communication groove 133 that communicates the mounting hole 123a with the first suction port 101, and the mounting hole 123a and the second discharge port 104 through the second discharge groove 132b. A discharge communication groove 134 that communicates with each other is formed. A piston 135 that blocks communication between the suction communication groove 133 and the discharge communication groove 134 is movably supported in the mounting hole 123a, and a lid member 137 is fixed via a compression coil spring 136. The compression coil spring 136 is urged and supported at a position where the piston 135 is urged by the urging force and the suction communication groove 133 and the discharge communication groove 134 are blocked.

  Therefore, as shown in FIG. 1, when the engine 21 is started, the oil pump 105 is driven synchronously, sucks oil from the suction ports 101 and 102, and discharges oil from the discharge ports 103 and 104. Then, oil is supplied to the control system A and the lubrication system B. That is, the oil pump 105 sucks the oil in the oil pan 107 from the first suction port 101 through the first suction passage 108, pressurizes it, and then discharges the oil from the first discharge port 103 to the first discharge passage 110. Supplied oil to the control system A. The oil pump 105 sucks the oil in the oil pan 107 from the second suction port 102 through the first suction passage 108 and the second suction passage 111 and pressurizes it, and then, from the second discharge port 104 to the second discharge passage 112. To discharge. Then, the discharged oil is supplied to the control system A through the third discharge passage 114 and the first discharge passage 110 or is supplied to the lubrication system B through the fourth discharge passage 115. In this case, the ECU 60 controls the supply amount of oil in the control system A and the lubrication system B by switching the switching valve 113 according to the operating state of the engine 21. That is, a large amount of oil is supplied to the control system A when the engine 21 is at a high speed or a high load.

  In the operation of the oil pump 105, the traction oil has a high viscosity, and the viscosity becomes higher at a low temperature. Therefore, when the engine 21 is cold started, the oil pump 105 sucks the high-viscosity traction oil. Discharging results in excessive driving torque and an increased pump load. However, in this embodiment, since the safety valve 106 is provided, at this time, the pump driving torque and the pump load are reduced by discharging the traction oil on the discharge side to the suction side.

  That is, as shown in FIGS. 4 and 5, normally, when the gears 126a, 126b, and 126c rotate, they are sucked from the first suction port 101 into the first suction recess 129a through the first suction groove 131a and added by the gear 126a. After being pressurized, the liquid is discharged from the first discharge recess 130a to the first discharge port 103 through the first discharge groove 132a. Further, the air is sucked from the second suction port 102 into the second suction recess 129b through the second suction groove 131b, pressurized by the gear 126c, and then discharged from the second discharge recess 130b to the second discharge port 104 through the second discharge groove 132b. To do.

  At this time, when the viscosity of the oil is high, the driving torque of the gears 126a, 126b, and 126c increases, and the discharge pressure of the oil at the discharge ports 103 and 104 increases. Then, the pressure of the second discharge port 104 acts on the piston 135 of the safety valve 106 through the discharge communication groove 134. In this case, the urging force of the compression coil spring 136 is set so that the piston 135 moves (releases) when the discharge pressure from the second discharge port 104 exceeds a predetermined pressure set in advance. Therefore, the piston 135 moves in the axial direction against the urging force of the compression coil spring 136 when the hydraulic pressure from the discharge communication groove 134 becomes larger than the urging force of the compression coil spring 136. Then, the second discharge port 104 and the first suction port 101 communicate with each other via the discharge communication groove 134, the mounting hole 123a, and the suction communication groove 133, and the oil in the second discharge port 104 is discharged to the discharge communication groove 134, the mounting hole. 123 a through the suction communication groove 133 and discharged to the first suction port 101. Therefore, the hydraulic pressure at the second discharge port 104 is reduced, the driving force of each gear 126a, 126b, 126c, that is, the pump load is reduced, and the pump driving torque of the engine 21 is also reduced.

  As described above, in the continuously variable transmission according to the first embodiment, the power roller 4 that contacts the input disk 2 to which the driving force from the engine 21 is transmitted and the output disk 3 that transmits the driving force to the wheels 27 is provided. By moving, a toroidal continuously variable transmission is configured by providing a hydraulic control device 9 for controlling the gear ratio, which is the rotation speed ratio between the input disk 2 and the output disk 3, by hydraulic pressure. 21 is provided with an oil pump 105 that discharges oil sucked from the suction ports 101 and 102 from the discharge ports 103 and 104, and a safety valve that opens and closes according to the discharge pressure from the second discharge port 104. 106 is provided.

  Therefore, when the oil discharge pressure at the second discharge port 104 rises abnormally, the safety valve 106 opens according to this discharge pressure, and the oil at the second discharge port 104 is discharged to the first suction port 101. The load on the pump 105 can be reduced and the durability can be improved. As a result, the pump drive torque can be reduced, the startability of the engine 21 can be improved, and the occurrence of insufficient lubricating oil can be prevented.

  In the continuously variable transmission of the first embodiment, the power roller 4 is tilted by changing the relative position of the power roller 4 with respect to the input disk 2 and the output disk 3 by hydraulic pressure, and the input disk 2 and the output disk 3 are The transmission ratio changing unit 5 that changes the rotation speed ratio, the input disk 2 and the output disk 3, and the power roller 4 are brought into contact with each other, and a clamping pressure that sandwiches the power roller 4 between the input disk 2 and the output disk 3 is applied. A hydraulic pressure pressing mechanism 15 is provided, and the hydraulic pressure control device 9 controls the gear ratio changing unit 5 and the hydraulic pressure pressing mechanism 15 by the hydraulic pressure from the oil pump 105. Therefore, when the engine 21 is started, oil can be supplied to at least the gear ratio changing unit 5 and the hydraulic pressure pressing mechanism 15, and the toroidal continuously variable transmission can be properly controlled.

  In the continuously variable transmission according to the first embodiment, the safety valve 106 is opened when the discharge pressure from the second discharge port 104 exceeds a predetermined pressure set in advance, and the oil in the second discharge port 104 is discharged to the first suction port. 101 is discharged. Therefore, by setting the predetermined pressure to the limit value of the pump load, the pump can be prevented from being damaged and the durability can be improved.

  Further, in the continuously variable transmission according to the first embodiment, the oil pump 103 is a gear pump that transports oil by meshing three gears 126a, 126b, and 126c in series. Accordingly, even oil having a low temperature and high viscosity can be reliably sucked, and since the two discharge ports 103 and 104 are provided, the discharge amount can be switched in a stepwise manner. Cost reduction can be made possible.

  FIG. 11 is a cross-sectional view of the oil pump in the toroidal continuously variable transmission according to the second embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the member which has the same function as what was demonstrated in the Example mentioned above, and the overlapping description is abbreviate | omitted.

  In the second embodiment, as shown in FIG. 11, the oil pump 141 includes a casing 121 that includes a pump body 122, a first pump cover 123, and a second pump cover 124, and three gears 126a, 126b, and 126c inside. It is rotatably accommodated in a state of meshing in series. A mounting hole 123a is formed in the first pump cover 123. The safety valve 106 is mounted in the mounting hole 123a, and a mounting hole 122a is formed in the pump body 122. A safety valve 142 is attached.

  That is, the pump body 122 is formed with a suction communication groove 143 that communicates with the mounting hole 122a and the second suction port 102 via the second suction groove 131b and the second suction recess 129b. A discharge communication groove 144 that communicates with the discharge port 103 via the first discharge groove 132a and the first discharge recess 130a is formed. A piston 145 that blocks communication between the suction communication groove 143 and the discharge communication groove 144 is movably supported in the mounting hole 122a, and a lid member 147 is fixed via a compression coil spring 146. The compression coil spring 146 is urged and supported at a position that urges the piston 145 by the urging force and blocks the suction communication groove 143 and the discharge communication groove 144.

  Note that the configuration and operation of the safety valve 106 are the same as those in the first embodiment, and a detailed description thereof will be omitted.

  Therefore, normally, when the gears 126a, 126b, and 126c rotate, they are sucked from the first suction port 101 through the first suction groove 131a into the first suction recess 129a, pressurized by the gear 126a, and then from the first discharge recess 130a. The ink is discharged to the first discharge port 103 through the first discharge groove 132a. Further, the air is sucked from the second suction port 102 into the second suction recess 129b through the second suction groove 131b, pressurized by the gear 126c, and then discharged from the second discharge recess 130b to the second discharge port 104 through the second discharge groove 132b. To do.

  At this time, when the viscosity of the oil is high, the driving torque of the gears 126a, 126b, and 126c increases, and the discharge pressure of the oil at the discharge ports 103 and 104 increases. Then, the pressure of the first discharge port 103 acts on the piston 145 of the safety valve 142 through the discharge communication groove 144. In this case, the urging force of the compression coil spring 146 is set so that the piston 145 moves (releases) when the discharge pressure from the first discharge port 103 exceeds a predetermined pressure set in advance. Therefore, the piston 145 moves in the axial direction against the biasing force of the compression coil spring 146 when the hydraulic pressure from the discharge communication groove 144 becomes larger than the biasing force of the compression coil spring 146. Then, the first discharge port 103 and the second suction port 102 communicate with each other via the discharge communication groove 144, the mounting hole 122a, and the suction communication groove 143, and the oil in the first discharge port 103 is discharged into the discharge communication groove 144 and the mounting hole. 122 a and the suction communication groove 143 is discharged to the second suction port 102. Therefore, the hydraulic pressure of the first discharge port 103 is reduced, the driving force of each gear 126a, 126b, 126c, that is, the pump load is reduced, and the pump driving torque of the engine 21 is also reduced.

  As described above, in the continuously variable transmission according to the second embodiment, the hydraulic control device 9 includes the oil pump 141 that is driven by the engine 21 and discharges the oil sucked from the suction ports 101 and 102 from the discharge ports 103 and 104. The oil pump 141 is provided with safety valves 106 and 142 that open and close according to the discharge pressures from the discharge ports 103 and 104, respectively.

  Therefore, when the oil discharge pressure at each discharge port 103, 104 rises abnormally, the safety valves 106, 142 are opened according to this discharge pressure, and the oil at each discharge port 103, 104 is discharged to each suction port 101, 102. Thus, the load on the oil pump 141 can be reduced and the durability can be improved. As a result, the pump drive torque can be reduced, the startability of the engine 21 can be improved, and the occurrence of insufficient lubricating oil can be prevented.

  In the continuously variable transmission of the second embodiment, the oil pump 141 is provided with the first discharge port 103 that discharges oil to the control system and the second discharge port 104 that discharges oil to the control system or the lubrication system. The switching valve 113 for switching the discharge destination of the second discharge port 104 in 141 according to the engine operating state is provided, the safety valve 106 is provided in the second discharge port 104, and the safety valve 142 is provided in the first discharge port 103. Therefore, by setting the discharge destination of the second discharge port 104 according to the operating state of the engine 21, the driving torque of the oil pump 103 can be reduced and the startability of the engine 21 can be improved. , 104 are provided with safety valves 106, 142, the load of the oil pump 141 can be reliably reduced.

  In the continuously variable transmission of the second embodiment, when the safety valve 142 is opened, the oil in the first discharge port 103 is discharged to the second suction port 102 side, and when the safety valve 106 is opened, the second discharge port. The oil 104 is discharged to the first suction port 101 side. Therefore, the discharge pressure at each of the discharge ports 103 and 104 can be efficiently reduced.

  In each of the above-described embodiments, the safety valve 106 is mounted on the first pump cover 123 and the safety valve 142 is mounted on the pump body 122. The mounting positions are the pump body 122, the first pump cover 123, and the second pump. Any of the covers 124 may be used. In addition, the casing 121 is configured by the pump body 122, the first pump cover 123, and the second pump cover 124, but may be configured integrally. Furthermore, although the configuration of the safety valves 106 and 142 is configured by the pistons 135 and 145 and the compression coil springs 136 and 146, the configuration is not limited to this configuration.

  In the above-described embodiment, the oil pump according to the present invention is configured as one oil pump 105 having two suction ports 101 and 102 and two discharge ports 103 and 104. Two oil pumps having a port and a discharge port may be used. The number of suction ports, discharge ports, and oil pumps is not limited to two, and three or more may be provided. In each embodiment, the discharge capacity of the first discharge port 103 in the oil pump is set to be smaller than the discharge capacity of the second discharge port 104. However, according to the oil (hydraulic pressure) required when starting the engine 21. What is necessary is just to set suitably.

  The continuously variable transmission according to the above-described embodiment of the present invention is not limited to the above-described embodiment, and various modifications can be made within the scope described in the claims. The continuously variable transmission according to the embodiment of the present invention may be configured by combining a plurality of the embodiments described above. In the above description, the continuously variable transmission has been described as a double-cavity toroidal continuously variable transmission, but the present invention is not limited thereto. Moreover, in the above description, although the rotational force transmission material was demonstrated as what is a wire, it is not restricted to this, A belt etc. may be sufficient.

  As described above, the continuously variable transmission according to the present invention improves the durability by reducing the load on the oil pump by providing the oil pump with a safety valve that opens and closes according to the discharge pressure from the discharge port. It is suitable for application to various half-toroidal continuously variable transmissions having a plurality of power rollers.

It is a schematic block diagram of the hydraulic control apparatus in the toroidal type continuously variable transmission which concerns on Example 1 of this invention. It is a side view of the oil pump by the hydraulic control apparatus of Example 1. It is a front view of the oil pump by the hydraulic control apparatus of Example 1. It is IV-IV sectional drawing of FIG. It is VV sectional drawing of FIG. 1 is a schematic cross-sectional view of a toroidal continuously variable transmission according to Embodiment 1. FIG. 1 is a configuration diagram of a main part of a toroidal continuously variable transmission according to Embodiment 1. FIG. It is a schematic diagram explaining the neutral position with respect to the input disk of the power roller with which the toroidal type continuously variable transmission of Example 1 is equipped. It is a schematic diagram explaining the speed change position with respect to the input disk of the power roller with which the toroidal type continuously variable transmission of Example 1 is equipped. FIG. 3 is a schematic plan view for explaining how to lay the synchronous wire of the toroidal continuously variable transmission according to the first embodiment. It is sectional drawing of the oil pump in the toroidal type continuously variable transmission which concerns on Example 2 of this invention.

Explanation of symbols

1 Toroidal continuously variable transmission (continuously variable transmission)
2 Input disk 3 Output disk 4 Power roller 5 Gear ratio changing part (cylinder mechanism)
6 trunnion 7 moving part 8 hydraulic piston part 9 hydraulic control device 10 input shaft 11 variator shaft 15 hydraulic pressure mechanism (clamping mechanism)
DESCRIPTION OF SYMBOLS 18 Synchronous mechanism 21 Engine 22 Torque converter 23 Forward / reverse switching mechanism 24 Power transmission mechanism 60 Electronic control unit, ECU (hydraulic switching control means)
DESCRIPTION OF SYMBOLS 101 1st suction port 102 2nd suction port 103 1st discharge port 104 2nd discharge port 105,141 Oil pump 106,142 Safety valve 107 Oil pan (oil storage part)
113 Switching valve A Control system (high pressure system)
B Lubrication system (low pressure system)

Claims (7)

A gear ratio which is a rotational speed ratio between the input disk and the output disk by moving a power roller in contact with an input disk to which the driving force from the engine is transmitted and an output disk for transmitting the driving force to the wheels. In a toroidal-type continuously variable transmission having a hydraulic control device for controlling the pressure by hydraulic pressure,
The hydraulic control device has an oil pump that is driven by the engine and discharges oil sucked from a suction port from a discharge port,
The oil pump is provided with a safety valve that opens and closes according to the discharge pressure from the discharge port ,
The oil pump has a first discharge port that discharges oil to a high-pressure system and a second discharge port that discharges oil to a high-pressure system or a low-pressure system, and the discharge destination of the second discharge port in the oil pump is an engine operation Provide a switching valve that switches between the high-pressure system and the low-pressure system according to the state,
The safety valve is provided in at least one of the first discharge port and the second discharge port;
A continuously variable transmission. A cylinder mechanism that tilts the power roller by hydraulically changing a relative position of the power roller with respect to the input disk and the output disk, and changes a rotational speed ratio between the input disk and the output disk;
A pressing mechanism that brings the input disk and the output disk into contact with the power roller, and that exerts a pressing force that sandwiches the power roller between the input disk and the output disk;
2. The continuously variable transmission according to claim 1, wherein the hydraulic control device controls the cylinder mechanism and the clamping mechanism by hydraulic pressure from the oil pump.   3. The safety valve according to claim 1, wherein the safety valve opens when a discharge pressure from the discharge port exceeds a predetermined pressure set in advance, and discharges oil from the discharge port to the suction port or the oil reservoir. The continuously variable transmission described in 1. The continuously variable transmission according to any one of claims 1 to 3, wherein the safety valve is provided in the first discharge port and the second discharge port.   5. The oil in the first discharge port is discharged to the second suction port side and the oil in the second discharge port is discharged to the first suction port side when the safety valve is opened. The continuously variable transmission described in 1.   The continuously variable transmission according to any one of claims 1 to 5, wherein the oil pump is a gear pump in which three gears mesh in series to transport oil.   The oil pump includes a pump body in which the gear is rotatably accommodated, and a pump cover that is fixed so as to cover the pump body and in which the suction port and the discharge port are formed. The continuously variable transmission according to claim 6.

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