JP2016118266A - Continuously variable transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain a structure that highly accurately performs control of a transmission ratio control valve for controlling a transmission ratio of a toroidal type continuously variable transmission when finely adjusting the transmission ratio of the toroidal type continuously variable transmission.SOLUTION: One end part in a long direction of a link member 42 is coupled to a stepping motor 30, and the other end part is coupled to a sleeve 5 of a control valve 1. In an intermediate part in the long direction of the link member 42, a long hole 44 is formed in a state of extending in the long direction, and an oscillation support shaft 45 is engaged to the long hole 44. The link member 42 can be displaced in an oscillatable manner with the oscillation support shaft 45 as a center. The oscillation support shaft 45 can be displaced along the long hole 44 by a motor 46 for oscillation center adjustment.SELECTED DRAWING: Figure 3

Description

  This invention is for generators (generators) used in, for example, automatic transmissions for vehicles (automobiles), automatic transmissions for construction machines (construction machinery), aircrafts (fixed wing aircraft, rotary wing aircraft, airships, etc.), etc. The present invention relates to an improvement of a continuously variable transmission incorporating a toroidal continuously variable transmission that is used as an automatic transmission or the like.

  Toroidal-type continuously variable transmissions used as automatic transmissions for automobiles are described in many publications such as Japanese Patent Application Laid-Open No. H10-260, and are well-known and partially implemented. Such a toroidal-type continuously variable transmission is configured by sandwiching a plurality of power rollers between an input side disk and an output side disk whose toroidal curved surfaces are opposite to each other in the axial direction. During operation, the rotation of the input side disk is transmitted to the output side disk through these power rollers. Each of these power rollers is rotatably supported by a support member such as a trunnion, and each of these support members is subjected to a swinging displacement about a pivot that is in a twisted position with respect to the central axes of both disks. Supported as possible. When changing the gear ratio between the two disks, the support members are displaced in the axial direction of the respective pivots by a hydraulic actuator. The supply / discharge of pressure oil to / from the actuator is controlled by a control valve while feeding back the movement of at least one of the support members.

  When the support members are displaced in the axial direction of the respective pivots based on supply / discharge of pressure oil to / from a pair of hydraulic chambers provided in the actuator, the peripheral surfaces of the power rollers, the input side, and the output side The direction of the tangential force acting on the rolling contact portion (traction portion) with the side surface of each disk changes (side slip occurs in the rolling contact portion). As the direction of the force changes, the support members swing (tilt) about their pivots, and the peripheral surfaces of the power rollers contact the side surfaces of the input and output disks. The position changes. If the peripheral surface of each of these power rollers is brought into rolling contact with the radially outward portion of the side surface of the input side disc and the radially inward portion of the side surface of the output side disc, The gear ratio is increased. On the other hand, if the peripheral surface of each power roller is brought into rolling contact with the radially inward portion of the side surface of the input side disk and the radially outward portion of the side surface of the output side disk, The gear ratio between the disks is on the deceleration side.

  As described above, the mechanism for adjusting the transmission ratio of the toroidal type continuously variable transmission to a desired value and maintaining the adjusted value will be described with reference to FIG. This mechanism includes a control valve 1, a stepping motor 2, and a recess cam 3. Among these, the control valve 1 is a combination of a spool 4 and a sleeve 5 that can be displaced relative to each other in the axial direction. Based on the relative displacement between the spool 4 and the sleeve 5, the oil pump 6 and the actuator 7. The supply / discharge state with the hydraulic chambers 8a and 8b is switched. The spool 4 and the sleeve 5 are relatively displaced by the movement of any one of the plurality of trunnions and the stepping motor 2. In the illustrated example, the movement of any one trunnion, that is, the displacement in the axial direction of the pivot 9 of any one trunnion and the swing displacement about the pivot 9 are used as the precess cam 3 and the link. The spool 4 is transmitted (feedback) to the spool 4 via the arm 10, and the spool 4 is displaced in the axial direction. On the other hand, the stepping motor 2 is configured to displace the sleeve 5 in the axial direction by a linear motion mechanism (not shown) such as a feed screw mechanism.

  When adjusting the gear ratio of the toroidal continuously variable transmission, the stepping motor 2 displaces the sleeve 5 to a predetermined position and opens the control valve 1 in a predetermined direction. Then, pressure oil is supplied to and discharged from the hydraulic chambers 8 a and 8 b of the actuators 7 attached to the trunnions in a predetermined direction, and the trunnions are moved in the axial direction of the pivots 9 by the actuators 7. Be displaced. As a result, the traction portions related to the power rollers supported by the trunnions are in a neutral position (the center of each traction portion includes the central axes of the input side disk and the output side disk, and the central axis of the pivot 9 is When the respective trunnions are displaced in the axial direction of the respective pivot shafts 9 {the original position (the state in which each of the traction portions is present in the neutral position) While returning to the position of each of the trunnions in the axial direction of the respective pivots 9), the trunnion is oscillated and displaced around this pivot 9. Then, the movement (axial direction and swing displacement) of the pivot shaft 9 of any one trunnion is transmitted to the spool 4 via the recess cam 3 and the link arm 10, and the spool 4 is displaced in the axial direction. . As a result, when each trunnion returns to its original position, the control valve 1 is closed, and the supply and discharge of the pressure oil to the hydraulic chambers 8a and 8b of each actuator 7 is stopped.

  When a toroidal continuously variable transmission as described above is incorporated into an actual automatic transmission for an automobile, it is combined with a gear type differential unit such as a planetary gear mechanism via a clutch device, and has a low speed mode and a high speed mode. It has hitherto been proposed to configure a step transmission. For example, Patent Document 2 describes a continuously variable transmission that can switch a rotation state of an output shaft between a forward rotation and a reverse rotation with a stop state (a so-called geared neutral state) while rotating an input shaft in one direction. ing. In the case of such a continuously variable transmission, the speed ratio of the continuously variable transmission as a whole changes to infinity in the low speed mode state. In other words, by adjusting the gear ratio of the toroidal-type continuously variable transmission, the rotation state of the output shaft can be converted into forward rotation and reverse rotation with the input shaft rotated in one direction with the stop state interposed therebetween. Become. In the case of such a continuously variable transmission capable of realizing a geared neutral state, in the vicinity of a value (geared neutral point, GN value) at which the output shaft can be stopped with respect to the transmission ratio of the toroidal type continuously variable transmission, Even if the gear ratio of the toroidal continuously variable transmission is slightly changed, the state of power transmitted to the output shaft is greatly changed. For this reason, it is necessary to perform the gear ratio control of the toroidal type continuously variable transmission with high accuracy.

  For example, with the vehicle stopped, the shift lever is moved from a non-traveling state such as the P range (parking position) or N range (neutral position) to the D range (normal forward position), L range (high drive forward position) or R range. When switching to a traveling state such as a range (reverse position), it is necessary to maintain a vehicle stop state by a braking force based on an operation of a brake pedal while quickly generating an appropriate driving force forward or backward. For this reason, it is necessary to strictly control the gear ratio of the toroidal type continuously variable transmission to a value (range) that can realize a state where the gear ratio is infinite while the shift lever is selected in the non-running state. is there. If the gear ratio of the toroidal-type continuously variable transmission deviates greatly from a value that can realize the state where the gear ratio is infinite, when the shift lever is selected to be in the traveling state, the driving force (which is greater than expected) Creep force) is transmitted, and the vehicle may start to move, or a driving force in a direction opposite to the driver's intention may be transmitted.

  In the case of a continuously variable transmission having a low speed mode and a high speed mode, the transmission ratio of the toroidal continuously variable transmission is determined from a value (mode switching point, MC value) at which mode switching between the low speed mode and the high speed mode is to be performed. If the connection / disconnection state of the clutch device is switched in a shifted state, a shift shock may occur, which may cause discomfort to the vehicle occupant. Therefore, it is required to perform the gear ratio control of the toroidal type continuously variable transmission with high accuracy from the viewpoint of smoothing the mode switching and suppressing the shift shock.

  Here, in order to perform the gear ratio control of the toroidal type continuously variable transmission incorporated in the continuously variable transmission with high accuracy, the stepping motor that displaces the sleeve 5 of the control valve 1 that is the gear ratio control valve in the axial direction. It is effective to reduce the resolution of 2 (increase the number of steps per rotation, decrease the step angle). However, if the resolution of the stepping motor 2 is made fine, the rotation speed of the stepping motor 2 becomes slow (the rotation angle per unit time becomes small), and the displacement speed in the axial direction of the sleeve 5 (the control valve 1). Valve opening speed) is slowed down. As a result, when the vehicle is suddenly accelerated or suddenly decelerated (emergency stop), there is a possibility that a sufficient shift speed of the toroidal continuously variable transmission cannot be secured.

  Japanese Patent Application Laid-Open No. 2003-228867 discloses a gear shift for controlling a gear ratio of a toroidal continuously variable transmission near a geared neutral point by switching an excitation method of a stepping motor for axially displacing a sleeve of a gear ratio control valve. A technique for controlling the ratio control valve with high accuracy is described. However, in the case of the invention described in Patent Document 3, if the stepping motor is driven with 1-2 phase excitation in order to control the transmission ratio control valve with high accuracy in the vicinity of the geared neutral point, The torque of the stepping motor is smaller than that in the case of driving, and idling (step out) is facilitated. Further, the control of the stepping motor becomes troublesome, and the driving circuit of the stepping motor may be complicated.

JP 2001-317601 A JP 2003-307266 A JP 2005-337285 A

  In view of the circumstances as described above, the present invention controls the transmission ratio control valve for controlling the transmission ratio of the toroidal type continuously variable transmission when finely adjusting the transmission ratio of the toroidal type continuously variable transmission. The invention was invented to realize a structure of a continuously variable transmission that can be performed with high accuracy.

A continuously variable transmission according to the present invention includes a differential having an input member that is rotationally driven in one direction by a power source such as an engine, a toroidal continuously variable transmission, a first input portion, and a second input portion. A unit, an output member for rotationally driving a driven part such as a drive wheel, and a controller for adjusting a gear ratio of the toroidal continuously variable transmission are provided.
Among these, the toroidal continuously variable transmission includes an input side disk, an output side disk, a plurality of power rollers, a plurality of support members, a hydraulic actuator, a transmission ratio control valve, and a transmission ratio adjustment. Means and a feedback mechanism.
Of these, the input side disk is rotationally driven by the input member together with the first input unit.
The output side disk is supported concentrically with the input side disk so as to be rotatable relative to the input side disk, and is connected to the second input unit.
Each of the power rollers is sandwiched between the input side disk and the output side disk.
Each of the support members rotatably supports each of the power rollers one by one and freely swings and displaces about a pivot provided at each end.
The actuator displaces the support members in the axial direction of the respective pivots to swing and displace the support members around the respective pivots, thereby changing the gear ratio between the input side disk and the output side disk. (The gear ratio of the toroidal type continuously variable transmission) is changed.
The speed ratio control valve switches the pressure oil supply / discharge state to the actuator based on the relative displacement of a pair of adjusting members (for example, a sleeve and a spool).
The speed ratio adjusting means displaces one of the adjusting members (for example, a sleeve).
The feedback mechanism includes a displacement in the axial direction of the pivot of any one of the support members and a swing displacement about the pivot of any one of the support members, the other of the two adjustment members. This is transmitted to the adjusting member (for example, spool).
The differential unit is formed by combining a plurality of gears. And the rotation according to the speed difference between said 1st input part and said 2nd input part is taken out, and it transmits to the said output member.
Further, the controller adjusts a gear ratio between the input side disk and the output side disk by adjusting a displacement amount of the one adjusting member by the speed ratio adjusting means, and the differential unit The relative displacement speeds of the plurality of gears constituting the are changed. As a result, the rotation direction of the output member can be converted to both directions with the stop state being sandwiched while the input member is rotated in one direction.

In particular, in the continuously variable transmission according to the present invention, the speed ratio adjusting means is combined with a pair of drive devices (actuators), so that a stepping motor which is at least one of these drive devices is used. Is configured to be capable of adjusting the displacement amount of the one adjusting member when it is driven by one step.
When the stepping motor is driven by one step, the amount of displacement of the one adjusting member is adjusted when the gear ratio between the input side disk and the output side disk is finely adjusted. Make it smaller than the case.

When implementing the continuously variable transmission apparatus of the present invention as described above, specifically, for example, the speed ratio adjusting means is composed of a link member, a stepping motor, and an oscillation center adjusting actuator. One end of the link member is coupled to the stepping motor, and the other end is coupled to the one adjusting member. In addition, the swing support shaft between the both ends of the link member is connected to each other by the swing center adjusting actuator such as a direct-acting stepping motor or a hydraulic actuator. The link member is provided so as to be displaceable in a direction of an imaginary straight line connecting the two, and the link member can be swung about the swing support shaft. Then, when the gear ratio between the input side disk and the output side disk is finely adjusted (for example, when the gear ratio of the toroidal continuously variable transmission is near the geared neutral point or near the mode switching point) In some cases, the position of the swing support shaft in the direction of the imaginary straight line is closer to the other end than the other cases (the side closer to the connecting portion with one adjusting member).
Alternatively, the transmission ratio adjusting means includes a first stepping motor and a second stepping motor having a smaller number of steps (a larger step angle) than the first stepping motor. When the gear ratio of the toroidal-type continuously variable transmission is finely adjusted, the one adjustment member is displaced by the first stepping motor, and in the other cases, the second stepping motor The adjustment member is displaced.

According to the continuously variable transmission of the present invention as described above, the displacement amount of one adjusting member when the stepping motor constituting the gear ratio adjusting means is driven by one step is calculated using the toroidal continuously variable transmission. When finely adjusting the gear ratio, it can be made smaller than in other cases. For this reason, when finely adjusting the gear ratio of the toroidal type continuously variable transmission, the gear ratio control valve for controlling the gear ratio of the toroidal type continuously variable transmission can be controlled with high accuracy. On the other hand, in other cases {particularly when the vehicle is suddenly accelerated or suddenly decelerated (emergency stop)}, the speed change speed of the toroidal continuously variable transmission can be sufficiently secured. .
Further, in the present invention, such a configuration can be realized without switching the excitation method of the stepping motor. Therefore, when finely adjusting the gear ratio of the toroidal continuously variable transmission, the stepping which constitutes the gear ratio adjusting means It is possible to prevent the motor torque from becoming small and the control of the stepping motor from becoming troublesome.

The block diagram of the continuously variable transmission used as the object of this invention. 1 is a hydraulic circuit diagram for gear ratio control according to a first example of an embodiment of the present invention. FIG. The schematic diagram (A) which shows the case where the main part is similarly taken out and the gear ratio of the toroidal type continuously variable transmission is finely adjusted, and the schematic diagram (B) showing the other cases. The figure similar to FIG. 3 which shows the 2nd example. FIG. 6 is a schematic cross-sectional view of a hydraulic control device portion for gear ratio control according to a conventional structure.

[First example of embodiment]
A first example of the embodiment of the present invention will be described with reference to FIGS. First, the continuously variable transmission of this example will be described with reference to the block diagram of FIG. In FIG. 1, a thick arrow indicates a power transmission path, a solid line indicates a hydraulic circuit, and a broken line indicates an electric circuit. The output of the engine 11 is input to an input shaft 13 that is an input member via a damper 12. The power transmitted to the input shaft 13 is transmitted from the hydraulic pressing device 15 constituting the toroidal-type continuously variable transmission 14 to the input side disk 16 and further to the output side disk 18 via the power roller 17. The Of these two discs 16, 18, the rotational speed of the input side disc 16 is measured by the input side rotational sensor 19, and the rotational speed of the output side disc 18 is measured by the output side rotational sensor 20, and is input to the controller 21. The gear ratio between the disks 16 and 18 is calculated.

  The power transmitted to the input shaft 13 is transmitted directly or via the toroidal continuously variable transmission 14 to the planetary gear type transmission 22 which is a differential unit. Then, the differential component of the constituent members of the planetary gear type transmission 22 is taken out to the output shaft 24 which is an output member via the clutch device 23. This clutch device 23 switches the power transmission state between the toroidal-type continuously variable transmission 14 and the planetary gear type transmission 22, and the low-speed clutch 25 and the high-speed clutch 26 shown in FIG. It represents. In the case of this example, the output shaft rotation sensor 27 detects the rotation speed of the output shaft 24 to determine whether or not the input side rotation sensor 19 and the output side rotation sensor 20 are defective. Fail safe is possible.

  On the other hand, the oil pump 6 is driven by the power extracted from the damper 12 portion, and the pressure oil discharged from the oil pump 6 is freely fed into the pressing device 15 and the control valve device 28. Among these, the control valve device 28 controls the displacement amount of the actuator 7 for displacing the trunnions 43a and 43b, which are support members supporting the power roller 17, in the axial direction of the pivot 9 (see FIG. 3). is there. The control valve 1 (see FIG. 2) constituting the control valve device 28 controls the supply and discharge of hydraulic pressure to the actuator 7. The hydraulic pressure in the pair of hydraulic chambers 8a and 8b (see FIG. 2) provided in the actuator 7 is detected by a hydraulic sensor 29 (the pair of hydraulic sensors 29a and 29b shown in FIG. 2), and the detection is performed. A signal is input to the controller 21. The controller 21 calculates a torque (passing torque) that passes through the toroidal continuously variable transmission 14 based on a signal from the hydraulic sensor 29 (hydraulic sensors 29a and 29b).

  The control valve device 28 includes a stepping motor 30 that constitutes a gear ratio adjusting means, a loading pressure control electromagnetic on-off valve 31, and a mode switching control electromagnetic on-off valve 32 (an electromagnetic valve 33 for a low-speed clutch shown in FIG. 2). The operating state can be switched by the high-speed clutch solenoid valve 34). The stepping motor 30, the loading pressure control electromagnetic on-off valve 31, and the mode switching control electromagnetic on-off valve 32 are all switched based on a control signal from the controller 21.

  In addition to the signals from the rotation sensors 19, 20, 27 and the hydraulic pressure sensor 29, the controller 21 includes a detection signal from the oil temperature sensor 35, a position signal from the position switch 36, and an accelerator sensor 37. A detection signal, a signal of the brake switch 38, and the like are input. Of these, the oil temperature sensor 35 detects the temperature of the lubricating oil (traction oil) in the casing that houses the continuously variable transmission. The position switch 36 emits a signal indicating an operation position (selection position) of a shift lever (operation lever) provided in the driver's seat for switching a manual hydraulic pressure switching valve 39 described later in FIG. It is. The accelerator sensor 37 is for detecting the opening of the accelerator pedal. Further, the brake switch 38 detects that the brake pedal has been depressed and generates a signal indicating that.

  Further, the controller 21 includes the stepping motor 30 and the electromagnetic valve for loading pressure control based on signals from the switches 36 and 38 and the sensors 19, 20, 27, 29, 35 and 37. In addition to sending the control signal to 31 and the electromagnetic switching valve 32 for mode switching control, a control signal for controlling the engine 11 is sent. Then, the transmission gear ratio between the input shaft 13 and the output shaft 24 is controlled, or is passed through the toroidal-type continuously variable transmission 14 at the time of stopping or traveling at a low speed and applied to the output shaft 24. Control torque (passing torque).

  FIG. 2 shows a hydraulic circuit for controlling the continuously variable transmission as described above. In this hydraulic circuit, the pressure oil sucked from the oil reservoir 40 and discharged by the oil pump 6 can be adjusted to a predetermined pressure by the pressure regulating valves 41a and 41b. Of these pressure regulating valves 41 a and 41 b, the adjustment pressure by the pressure regulating valve 41 a for adjusting the pressure oil sent to the manual hydraulic pressure switching valve 39 side can be adjusted based on the opening and closing of the electromagnetic pressure regulating valve 31 for loading pressure control. It is said. The pressure oil whose pressure has been adjusted by the pressure regulating valves 41 a and 41 b can be sent to the actuator 7 via the control valve 1.

  The pressure oil can be fed into the hydraulic chamber of the low speed clutch 25 or the high speed clutch 26 via the manual hydraulic pressure switching valve 39 and the low speed clutch electromagnetic valve 33 or the high speed clutch electromagnetic valve 34. . Of these, the low speed clutch 25 is connected when realizing a low speed mode in which the reduction ratio is increased (including an infinite transmission ratio) and disconnected when realizing a high speed mode in which the reduction ratio is reduced. It is. On the other hand, the high speed clutch 26 is disconnected when realizing the low speed mode and is connected when realizing the high speed mode. Further, the supply / discharge state of the pressure oil to the low speed clutch 25 and the high speed clutch 26 is detected by hydraulic sensors 29c and 29d, respectively, and a detection signal is input to the controller 21.

  FIG. 1 shows an adjusting device for adjusting the transmission ratio of the toroidal type continuously variable transmission 14 incorporated in the continuously variable transmission of this example as described above to a desired value and maintaining the adjusted value. 2 will be described with reference to FIG. This adjusting device includes the control valve 1, the recess cam 3, the link arm 10, the stepping motor 30, and a link mechanism 49 (link member 42, swing support shaft 45, swing center adjusting motor 46). Prepare. Of these, the control valve 1 is a combination of a spool 4 and a sleeve 5, each of which is an adjustment member, capable of relative displacement in the axial direction. Based on the relative displacement between the spool 4 and the sleeve 5, an oil pump 6 and the hydraulic chambers 8a and 8b of the actuator 7 are switched. Further, the spool 4 and the sleeve 5 are relatively displaced by the movement of one trunnion 43a (right side in FIG. 3) of the trunnions 43a and 43b and the stepping motor 30. Yes. That is, the displacement of the trunnion 43a in the axial direction of the pivot 9 and the swing displacement about the pivot 9 are transmitted (feedback) to the spool 4 via the recess cam 3 and the link arm 10, and the spool 4 Is displaced in the axial direction. On the other hand, the stepping motor 30 is configured to displace the sleeve 5 in the axial direction via a linear motion mechanism (not shown) such as a feed screw mechanism and the link mechanism 49 (link member 42). For this purpose, a long hole 44 is formed in an intermediate portion in the length direction of the link member 42 so as to extend in the length direction, and the swing support shaft 45 is formed in the long hole 44. Engagement (insertion) is possible along the displacement. As a result, the link member 42 can be swung about the swing support shaft 45. Of the link member 42, one end portion in the length direction (the lower end portion in FIGS. 2 and 3) is displaced to the stepping motor 30, and the displacement of the output shaft of the stepping motor 30 in the axial direction (the axial direction of the linear motion mechanism) The other end (the upper end in FIGS. 2 and 3) is coupled to the sleeve 5 of the control valve 1 so as to allow displacement in the axial direction of the sleeve 5. Particularly in this example, the swing support shaft 45 can be driven along the long hole 44 by the swing center adjusting motor 46. The swing center adjusting motor 46 is constituted by, for example, a direct-acting stepping motor. However, the swing support shaft 45 can be configured to be driven along the long hole 44 by a hydraulic actuator or the like.

In the continuously variable transmission of this example as described above, when the gear ratio of the toroidal continuously variable transmission 14 is finely adjusted, that is, the gear ratio e _{CVU of the} toroidal continuously variable transmission 14 is in the vicinity of the geared neutral point. FIG. 3A shows a case where {for example, GN value (1.306) ± 0.1} and a mode switching point vicinity {for example, MC value (0.46) ± 0.1}. As shown, the swing support shaft 45 serving as the swing center (fulcrum) of the link member 42 is driven by the swing center adjusting motor 46 to connect the upper end of the long hole 44 (connected to the sleeve 5). On the end of the side). On the other hand, in other cases (when the gear ratio of the toroidal continuously variable transmission 14 is not finely adjusted), the swing support shaft 45 is driven by the swing center adjusting motor 46, and the long hole 44 is positioned at a lower end portion (an end portion on the side connected to the stepping motor 30) or an intermediate portion. As a result, when the stepping motor 30 is driven by one step, the swing angle of the ring member 42 around the swing support shaft 45, and thus the axial displacement of the sleeve 5 is obtained. Is made smaller when the gear ratio of the toroidal-type continuously variable transmission 14 is finely adjusted than in other cases.

  In the case of the continuously variable transmission of this example as described above, the amount of axial displacement of the sleeve 5 when the stepping motor 30 is driven by one step is determined as the shift of the toroidal continuously variable transmission 14. When the ratio is finely adjusted, it can be made smaller than in other cases. Therefore, when the gear ratio of the toroidal continuously variable transmission 14 is finely adjusted, the control valve 1 can be controlled with high accuracy. . On the other hand, in other cases {particularly when the vehicle is suddenly accelerated or suddenly decelerated (emergency stop)}, the stepping motor 30 is driven by one step. The amount of axial displacement can be increased, and the shift speed of the toroidal-type continuously variable transmission 14 can be sufficiently secured. In the case of this example, the control of the control valve 1 can be performed with high accuracy, so that the swing support shaft 45 serving as the swing center of the link member 42 is connected to the length direction of the link member 42. This is realized by making it displaceable (changing the fulcrum of the link member 42). Therefore, unlike the invention described in the above-mentioned Patent Document 3, when finely adjusting the gear ratio of the toroidal continuously variable transmission, the torque of the stepping motor does not decrease (rather, increases due to the lever principle). ). In addition, the control of the stepping motor can be prevented from being troublesome.

  In the case of the continuously variable transmission of this example, the axial displacement amount of the sleeve 5 when the stepping motor 30 is driven by one step, the gear ratio of the toroidal continuously variable transmission 14 is near the geared neutral point. And the case near the mode switching point are the same, but can be different from each other. That is, for example, when the gear ratio of the toroidal-type continuously variable transmission 14 is in the vicinity of the geared neutral point, the swing support shaft 45 is positioned at the upper end of the long hole 44 and is also in the vicinity of the mode switching point. The oscillating support shaft 45 is positioned in the middle portion of the long hole 44. Thereby, when the gear ratio of the toroidal type continuously variable transmission 14 is in the vicinity of the geared neutral point, the control valve 1 can be controlled with higher accuracy than in the case of the vicinity of the mode switching point. In short, in the case of the continuously variable transmission of this example as described above, the shaft of the sleeve 5 when the stepping motor 30 is driven by one step within a range in which the swing support shaft 45 can be displaced within the long hole 44. The amount of directional displacement can be adjusted, and the accuracy of the gear ratio control and the speed of the toroidal-type continuously variable transmission 14 are appropriately determined {stepless (not limited to a smooth and continuous stepless process, for example, 20 to 30 steps, Including the case of multi-stages close to a continuous state).

[Second Example of Embodiment]
A second example of the embodiment of the present invention will be described with reference to FIG. In the case of the continuously variable transmission of this example, the mechanism for adjusting the transmission ratio of the toroidal type continuously variable transmission 14 (see FIG. 1) to a desired value and holding the adjusted value is the control valve 1, The first stepping motor 47 and the number of steps smaller than the first stepping motor 47 (the rotation angle per step is large. For example, the number of steps is 1/3 of the number of steps of the first stepping motor 47. A second stepping motor 48 (about 2/3) and a link mechanism 49a (link member 42a, swing support shaft 45a). Of these, the first stepping motor 47 displaces the sleeve 5 of the control valve 1 in the axial direction via a linear motion mechanism (not shown) such as a feed screw mechanism and the link mechanism 49a (link member 42a). It is possible. For this purpose, the link member 42a is supported so as to be capable of swinging displacement about a swing support shaft 45a provided at the intermediate portion in the length direction (in the present example, provided undisplaceable). Of the link member 42a, one end (the lower end in FIG. 4) in the length direction is coupled to the first stepping motor 47, and the other end (the upper end in FIG. 4) is connected to the sleeve 5. Are connected. Particularly in the case of this example, the second stepping motor 48 is installed via the second linear motion mechanism so that the first stepping motor 47 can be displaced in the axial direction of the output shaft ( It is coupled to a supported stage (not shown). That is, the second stepping motor 48 is connected to the sleeve of the control valve 1 via the second linear motion mechanism, the first stepping motor 47 (and the linear motion mechanism), and the link mechanism 49a. 5 can be displaced in the axial direction.

  In the case of the continuously variable transmission of this example as described above, when the gear ratio of the toroidal type continuously variable transmission 14 is in the vicinity of the geared neutral point or the mode switching point, The sleeve 5 of the control valve 1 is displaced in the axial direction by the first stepping motor 47 having a larger number of steps than the second stepping motor 48. On the other hand, in other cases (when the gear ratio of the toroidal type continuously variable transmission 14 is not finely adjusted), the second stepping motor 48 having a smaller number of steps than the first stepping motor 47 is used. The sleeve 5 of the control valve 1 is displaced in the axial direction.

  According to such a continuously variable transmission of this example, when it is necessary to finely adjust the gear ratio of the toroidal continuously variable transmission 14, the gear ratio can be controlled with high accuracy. In other cases {particularly when the vehicle is accelerated or decelerated (emergency stopped)}, the shift speed of the toroidal continuously variable transmission 14 can be sufficiently secured.

When the continuously variable transmission of this example is implemented, if the torque of the first and second stepping motors 47 and 48 can be sufficiently secured, the excitation of the first and second stepping motors 47 and 48 can be performed. By switching the system, it is possible to adjust the speed ratio control accuracy and the speed of the toroidal type continuously variable transmission 14 more finely (in multiple stages). Also, the first and second stepping motors 47 and 48 can be exchanged.
Other configurations and operations are the same as those of the first example of the embodiment described above.

DESCRIPTION OF SYMBOLS 1 Control valve 2 Stepping motor 3 Precess cam 4 Spool 5 Sleeve 6 Oil pump 7 Actuator 8a, 8b Hydraulic chamber 9 Axis 10 Link arm 11 Engine 12 Damper 13 Input shaft 14 Toroidal type continuously variable transmission 15 Pressing device 16 Input side disk 17 Power Roller 18 Output side disk 19 Input side rotation sensor 20 Output side rotation sensor 21 Controller 22 Planetary gear type transmission 23 Clutch device 24 Output shaft 25 Low speed clutch 26 High speed clutch 27 Output shaft rotation sensor 28 Control valve device 29, 29a ˜29d Hydraulic pressure sensor 30 Stepping motor 31 Electromagnetic on / off valve for loading pressure control 32 Solenoid on / off valve for mode switching control 33 Solenoid valve for low speed clutch 34 Solenoid valve for high speed clutch 35 Oil temperature sensor 36 Position switch 37 Accelerator sensor 38 Brake switch 39 Manual oil pressure switching valve 40 Oil reservoir 41a, 41b Pressure regulating valve 42, 42a Link member 43a, 43b Trunnion 44 Long hole 45, 45a Oscillation support shaft 46 Oscillation center adjustment motor 47 First stepping motor 48 Second stepping motor 49, 49a Link mechanism

Claims (1)

An input member that is rotationally driven in one direction by a power source, a toroidal-type continuously variable transmission, a differential unit having a first input portion and a second input portion, and for driving the driven portion to rotate An output member, and a controller for adjusting a gear ratio of the toroidal continuously variable transmission,
This toroidal type continuously variable transmission is
An input side disk that is rotationally driven by the input member together with the first input unit;
An output side disk connected to the second input unit, concentrically with the input side disk and supported to be freely rotatable relative to the input side disk;
A plurality of power rollers sandwiched between the input side disk and the output side disk;
A plurality of support members each rotatably supporting the power rollers one by one, and capable of freely oscillating displacement about a pivot provided at each end;
Hydraulic pressure that displaces each of the support members in the axial direction of the respective pivots and swings and displaces each of the support members about the respective pivots to change a gear ratio between the input side disk and the output side disk. An actuator of the type,
A transmission ratio control valve that switches a supply / discharge state of pressure oil to the actuator based on a relative displacement of a pair of adjustment members;
Transmission ratio adjusting means for displacing one of the adjusting members;
The displacement in the axial direction of the pivot of any one of the support members and the swing displacement about the pivot of any one of the support members are transmitted to the other adjustment member of the both adjustment members. With a feedback mechanism and
The differential unit is formed by combining a plurality of gears, takes out rotation according to a speed difference between the first input unit and the second input unit, and transmits the rotation to the output member,
The controller adjusts a gear ratio between the input side disk and the output side disk by adjusting a displacement amount of the one adjusting member by the speed ratio adjusting means, and constitutes the differential unit. By changing the relative displacement speeds of the plurality of gears, the rotation direction of the output member can be converted to both directions with the stop state sandwiched while the input member is rotated in one direction.
In the continuously variable transmission,
The gear ratio adjusting means is a combination of a pair of drive devices, so that the displacement of the one adjusting member when the stepping motor, which is at least one of the two drive devices, is driven by one step. A continuously variable transmission characterized in that the amount is adjustable.

Images