JP2009197892A - Continuously variable transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To appropriately regulate fastening pressures of a low-speed clutch 7 and high-speed clutch 8 in accordance with an operating condition. <P>SOLUTION: Pressurized oil is fed to respective hydraulic chambers 52a, 52b of a low-speed clutch 7 and high-speed clutch 8 through a system separate from a primary line 50 for introducing the pressurized oil to a hydraulic chamber 51 of a pressing device 14. In this case, oil pressure introduced to the low-speed clutch 7 and high-speed clutch 8 is adjusted by PWM controlling respective solenoid valves 45, 46 for the low-speed clutch 7 and high-speed clutch 8 on the basis of a passing torque (differential pressure corresponding to a passing torque) of a toroidal continuously variable transmission and output torque (accelerator operation amount corresponding to output torque) of an engine connected with the toroidal continuously variable transmission. <P>COPYRIGHT: (C)2009,JPO&INPIT

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 used as an automatic transmission or the like. Specifically, the structure which controls appropriately the fastening pressure of a clutch apparatus according to a driving | running condition is implement | achieved.

  The use of a toroidal continuously variable transmission as a vehicle (automobile) transmission is described in, for example, many publications and is well known in some implementations. Also, a continuously variable transmission that combines a toroidal continuously variable transmission and a differential unit (for example, a planetary gear transmission that is a gear-type differential unit) in order to increase the fluctuation range of the transmission ratio is disclosed in, for example, a patent. Conventionally, it is widely known, for example, as described in Documents 1 to 4. Among these, Patent Documents 1 and 2 describe a mode in which power is transmitted only by a toroidal-type continuously variable transmission (low-speed mode), and main power is transmitted by a planetary gear type transmission that is a differential unit. A continuously variable transmission having a mode (high speed mode) that realizes a so-called power split state in which a gear ratio is adjusted by a continuously variable transmission is described. Further, Patent Documents 3 to 4 describe a mode in which a so-called geared neutral state can be realized in which the rotation state of the output shaft can be switched between forward rotation and reverse rotation with the input shaft rotated in one direction. A continuously variable transmission with a low speed mode is described.

  FIGS. 8 to 9 show continuously variable transmissions having a mode described in Patent Documents 3 to 4 that can realize a geared neutral state. Of these, FIG. 8 shows a block diagram of the continuously variable transmission, and FIG. 9 shows a hydraulic circuit for controlling the continuously variable transmission. The output of the engine 1 is input to the input shaft 3 via the damper 2. The power transmitted to the input shaft 3 is transmitted to the planetary gear type transmission 5 which is a differential unit, either directly or via the toroidal continuously variable transmission 4. The differential components of the constituent members of the planetary gear type transmission 5 are taken out to the output shaft 9 via the clutch device 6, that is, the low speed and high speed clutches 7 and 8 shown in FIG. The toroidal-type continuously variable transmission 4 has input and output disks 10 and 11 corresponding to the first and second disks, respectively, and a plurality of power rollers 12, each corresponding to a support member. A plurality of trunnions (not shown), an actuator 13 (FIG. 9), a pressing device 14, and a transmission ratio control unit 15.

  Of these, the input-side and output-side disks 10 and 11 are arranged concentrically and relatively freely rotatable. Each of the power rollers 12 is sandwiched between the inner surfaces of the input and output disks 10 and 11 facing each other, and the power roller 12 is driven between the input and output disks 10 and 11. (Force, torque) is transmitted. Each trunnion supports each power roller 12 rotatably. The actuator 13 is of a hydraulic type, and the trunnions supporting the power rollers 12 are displaced in the axial directions of the pivots provided at both ends so that the input side disk 10 and the output side The gear ratio with the disk 11 is changed. The pressing device 14 is of a hydraulic type that generates a pressing force proportional to the hydraulic pressure with the introduction of the hydraulic pressure, and presses the input side disk 10 and the output side disk 11 in a direction approaching each other. . The gear ratio control unit 15 controls the displacement direction and the displacement amount of the actuator 13 so that the gear ratio between the input side disk 10 and the output side disk 11 becomes a desired value.

  In the case of the illustrated example, the transmission ratio control unit 15 includes a controller (ECU) 16, a stepping motor 17 that is switched based on a control signal from the controller 16, a line pressure control electromagnetic on-off valve 18, and the like. The solenoid valve 19, the shift solenoid valve 20, and the control valve device 21 whose operation state can be switched by these members 17 to 20. The control valve device 21 includes a transmission ratio control valve 22, a differential pressure cylinder 23, correction control valves 24a and 24b, and high-speed clutch and low-speed clutch switching valves 25 and 26 (FIG. 9). It is a combination. Of these, the gear ratio control valve 22 controls the supply and discharge of hydraulic pressure to the actuator 13. Further, the differential pressure cylinder 23 is configured to control the transmission ratio control valve so as to correct the transmission ratio of the toroidal type continuously variable transmission 4 according to the force (passing torque) passing through the toroidal type continuously variable transmission 4. This is for adjusting the switching state of 22. The correction control valves 24 a and 24 b control the supply and discharge of pressure oil to and from the differential pressure cylinder 23. Further, the switching valves 25 and 26 for the high speed clutch and the low speed clutch switch the introduction state of the pressure oil to the low speed and high speed clutches 7 and 8, respectively.

  Further, the pressure oil discharged from the oil pump 27 (27a, 27b in FIG. 9) driven by the power extracted from the damper 2 portion is sent to the control valve device 21, the pressing device 14, and the like. That is, the pressure oil sucked from the oil reservoir 28 (FIG. 9) and discharged by the oil pumps 27a and 27b is adjusted to a predetermined pressure by the pressing force adjusting valve 29 and the low pressure side adjusting valve 30 (FIG. 9). It is free. Of these adjusting valves 29 and 30, the pressing force adjusting valve 29 for adjusting the hydraulic pressure sent to the pressing device 14 and the manual hydraulic pressure switching valve 31 is described in detail in, for example, Patent Document 5 and the like. In addition, it has a function as a relief valve, and includes first to third pilot portions 32 to 34. Of these, the first and second pilot portions 32 and 33 control the opening pressure of the pressing force adjusting valve 29 according to the magnitude of the force (passing torque) passing through the toroidal-type continuously variable transmission 4. It is for adjusting. For this purpose, there exists between a pair of hydraulic chambers 36a and 36b provided with a piston 35 sandwiched between an actuator 13 for displacing a support member (trunnion) for supporting the power roller 12 in the axial direction of the pivot axis. A hydraulic pressure difference (differential pressure) is introduced into the first and second pilot parts 32 and 33 via a differential pressure take-out valve 37.

  On the other hand, the third pilot portion 34 is a transmission ratio of the toroidal type continuously variable transmission 4, the temperature of the lubricating oil (traction oil) existing in the toroidal type continuously variable transmission 4, and a drive source. This is for adjusting the valve opening pressure of the pressure adjusting valve 29 according to operating conditions other than the passing torque (corresponding differential pressure) such as the rotational speed of a certain engine 1. That is, the valve opening pressure of the pressure adjusting valve 29 is adjusted according to the passing torque (corresponding to the differential pressure) (adjusted by the first and second pilot parts 32 and 33), The pressure is adjusted (reduced) to a target value corresponding to the optimum pressing force to be generated by the pressing device 14 in accordance with operating conditions other than (the differential pressure corresponding to) the passing torque. For this purpose, pressure oil of a predetermined pressure is introduced into the third pilot portion 34 based on the opening / closing (duty ratio control) of the line pressure control electromagnetic switching valve 18 controlled by a command from the controller 16. Yes. Then, by appropriately adjusting the hydraulic pressure introduced into the first to third pilot parts 32 to 34, {according to the magnitude of the passing torque (differential pressure) in the first and second pilot parts 32 and 33 By introducing the hydraulic pressure and introducing the hydraulic pressure adjusted based on the command of the controller 16 to the third pilot section 34, the opening pressure of the pressing force adjusting valve 29, and thus the pressing device The pressing force generated by 14 is appropriately regulated in accordance with the operation status of the toroidal type continuously variable transmission 4.

  For example, FIG. 10 shows the relationship between the opening degree of the line pressure control electromagnetic on-off valve 18 (the ratio of the open time per unit time) and the pressure reduction amount (the amount of decrease in the valve opening pressure of the pressing force adjusting valve 29). An example is shown. Based on such a relationship, the controller 16 adjusts the opening / closing of the line pressure control electromagnetic on / off valve 18 (duty ratio control), thereby opening the pressure of the pressing force adjusting valve 29, and thus the pressing pressure. By adjusting the hydraulic pressure introduced into the device 14 to the target value, the pressing force generated by the pressing device 14 is appropriately regulated.

  Further, the pressure oil adjusted by the pressing force adjusting valve 29 is supplied to the low speed clutch via the manual hydraulic pressure switching valve 31, the pressure reducing valve 38, the high speed clutch switching valve 25 or the low speed clutch switching valve 26. The clutch 7 or the high-speed clutch 8 can be fed into the hydraulic chambers 52a and 52b. The low speed clutch 7 out of the low speed and high speed clutches 7 and 8 is connected when realizing a low speed mode in which the reduction ratio is increased (including an infinite gear ratio (including a geared neutral state)). At the same time, the connection is broken when the high speed mode for reducing the reduction ratio is realized. In contrast, the high speed clutch 8 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 and high speed clutches 7 and 8 is switched according to the switching of the shift solenoid valve 20.

  FIG. 11 shows an example of the relationship between the speed ratio (speed increase ratio) of the toroidal type continuously variable transmission 4 and the speed ratio (speed increase ratio) of the continuously variable transmission as a whole. For example, in the low speed mode in which the low speed clutch 7 is connected and the high speed clutch 8 is disconnected, the transmission ratio of the toroidal continuously variable transmission 4 can be realized in the GN state as indicated by the solid line α. As the speed is decelerated from the value (GN value), the speed ratio of the continuously variable transmission as a whole is increased from the stopped state (speed ratio 0 state) to the forward direction (+: forward rotation direction). Similarly, as the speed increases from the GN value, the speed is also increased in the backward direction (-: reverse direction) from the stopped state. On the other hand, in the high speed mode in which the high speed clutch 8 is connected and the low speed clutch 7 is disconnected, as indicated by the solid line β, the speed ratio of the toroidal continuously variable transmission 4 is increased. The speed ratio of the continuously variable transmission as a whole can be increased (in the forward direction).

  In general, “speed ratio” is a reduction ratio, “speed ratio” is an increase ratio, and the reciprocal of “speed ratio” is “speed ratio” (“speed ratio” = 1 / “ Gear ratio "). However, in the present specification and claims, the term “speed ratio” is used for the ratio between the input side and the output side for the toroidal type continuously variable transmission, and the input side for the entire continuously variable transmission is The term “speed ratio” is used for the ratio to the output side. The reason for this is to make it easy to clarify whether it is the ratio of the toroidal type continuously variable transmission or the ratio of the continuously variable transmission as a whole. Therefore, in the present specification and claims, the “speed ratio” does not necessarily correspond to the reduction ratio, and the “speed ratio” does not necessarily correspond to the speed increase ratio.

  In a vehicle incorporating a continuously variable transmission as described above, based on the vehicle's current driving condition (driving condition) obtained from the accelerator pedal operation (accelerator opening) and the vehicle's driving speed (vehicle speed). The controller 16 obtains the optimum speed ratio (target speed ratio) of the continuously variable transmission. Then, in order to realize this target speed ratio, the stepping motor 17 is driven based on the control signal of the controller 16 and the speed ratio control valve 22 is switched, so that the speed ratio of the toroidal type continuously variable transmission 4 is The target speed ratio corresponding to the target speed ratio is adjusted. In addition, by switching the shift solenoid valve 20 as necessary (in accordance with the target speed ratio of the continuously variable transmission), the connection state of the low speed and high speed clutches 7 and 8 is switched. Select the required travel mode (low speed mode or high speed mode). Thus, the speed ratio of the continuously variable transmission is adjusted to an optimum value (target speed ratio) according to the running state of the vehicle at that time.

  By the way, the toroidal continuously variable transmission 4 and the planetary gear type transmission 5 as described above are combined through the clutch device 6 (7, 8), and the low speed mode (first mode) and the high speed mode ( In the case of the continuously variable transmission having the second mode), the above-described geared neutral state can be realized, or the power split state as described in Patent Documents 1 and 2 can be realized. Smooth switching of the mode at the time of switching between the low speed mode and the high speed mode is important from the viewpoint of ensuring ride performance (good ride quality) and durability. As a technique for smoothly performing such mode switching, for example, Patent Document 6 describes a technique for simultaneously connecting a clutch that has not been connected and a clutch that has been connected so far when the mode is switched. Has been. By adopting such a technique, for example, when the mode is switched during acceleration, it is possible to prevent a sudden increase in engine speed due to the simultaneous disconnection of both the low speed clutch and the high speed clutch. Further, it is possible to prevent a shift shock (a feeling of torque loss and a feeling of pushing out) that accompanies the connection of the high speed clutch after the sudden rise, and it is possible to prevent the driver and other passengers from feeling uncomfortable. Further, it is possible to reduce the impact applied to each component when the mode is switched, and to secure durability.

  In the case of the continuously variable transmission shown in FIGS. 8 to 9 described above, the pressing force generated by the pressing device 14 is adjusted in accordance with the torque (passing torque) passing through the toroidal continuously variable transmission 4. In addition, the hydraulic pressure corresponding to the hydraulic pressure difference (differential pressure) between the pair of hydraulic chambers 36a and 36b constituting the actuator 13 is adjusted (via the differential pressure extracting valve 37). It is introduced into the first and second pilot chambers 32, 33). On the other hand, instead of such a structure in which the differential pressure is directly introduced into the pressing force adjusting valve 29, hydraulic sensors 39a and 39b (39 in FIG. 8) provided in the pair of hydraulic chambers 36a and 36b constituting the actuator 13, respectively. It is also conceivable to detect the differential pressure by adjusting the pressure generated by the pressing device 14 based on this differential pressure (or the passing torque obtained from this differential pressure). When such a configuration is employed, the hydraulic pressure chambers 36a and 36b constituting the actuator 13 and the pressing force adjustment valve 29 are communicated with each other as shown in FIG. The hydraulic circuit {differential pressure take-out valve 37 (FIG. 9), hydraulic piping, etc.] for this purpose can be omitted.

  When the configuration as described above is adopted, the controller 16 detects the differential pressure (passing torque) detected by each of the hydraulic sensors 39a and 39b, the gear ratio of the toroidal continuously variable transmission 4, and as necessary. The target value of the hydraulic pressure to be introduced into the hydraulic chamber 51 of the pressing device 14 is set (calculated) according to other state quantities such as the oil temperature circulating in the toroidal continuously variable transmission 4. In this case, the speed ratio is determined by, for example, the input side and output side rotational speed sensors 40 and 41 for detecting the rotational speeds of the input side and output side disks 10 and 11 (the rotational speeds of both disks 10 and 11). As a ratio). The oil temperature can be detected by, for example, an oil temperature sensor 42 provided in the casing of the toroidal continuously variable transmission 4. Further, the target value is obtained in advance by experiment or calculation as a correlation between the value such as the differential pressure (passing torque), the gear ratio, the oil temperature, and the target value corresponding to these values, for example. The memory of the controller 16 is stored as a map (MAP) or a calculation formula. Such a controller 16 sets (calculates and obtains) the target value corresponding to the differential pressure (passing torque), gear ratio, oil temperature, etc. at that time using these maps and calculation formulas. In addition, the opening / closing of the line pressure control electromagnetic on-off valve 18 is adjusted (duty ratio control) to adjust to the target value. Then, based on the opening / closing adjustment, the valve opening pressure of the pressing force adjusting valve 29 and the hydraulic pressure introduced into the hydraulic chamber 51 of the pressing device 14 are adjusted to the target value, and the pressing force generated by the pressing device 14 is adjusted. Regulate pressure appropriately.

  By the way, in the case of the structure shown in FIGS. 8 to 9 described above, the pressure oil in the primary line 50 adjusted by the pressing force adjusting valve 29 is supplied to the manual hydraulic pressure switching valve 31 and the pressure reducing valve 38 in addition to the pressing device 14. The low-speed clutch and the high-speed clutch 7 and 8 are also introduced via the low-speed clutch and high-speed clutch switching valves 25 and 26, respectively. That is, in the state where the pressure oil of the primary line 50 adjusted by the pressing force adjusting valve 29 is reduced to a predetermined pressure (for example, 1.4 [MPa] in the hydraulic circuit of FIG. 9) by the pressure reducing valve 38, the low speed The low-speed and high-speed clutches 7 and 8 are connected by introducing them into the high-speed and high-speed clutches 7 and 8.

  12 shows the speed ratio of the continuously variable transmission as a whole, the loading pressure corresponding to the hydraulic pressure to be introduced into the hydraulic chamber 51 of the pressing device 14 at the maximum torque, and the low speed and high speed clutches 7, respectively. 8 shows an example of the relationship with the required clutch pressure corresponding to the hydraulic pressure to be introduced into the eight hydraulic chambers 52a and 52b. The loading pressure corresponds to the hydraulic pressure of the primary line 50 that is adjusted according to the differential pressure (passing torque). The required clutch pressure is a hydraulic pressure corresponding to the fastening pressure to be generated in each of the low speed and high speed clutches 7 and 8 (power is transmitted without causing slippage in the low speed and high speed clutches 7 and 8. Corresponding to the required hydraulic pressure). Such a required clutch pressure can be obtained from the following equation (1) as described in Non-Patent Document 1, for example.

この式（１）中、Ｔc はクラッチ装置の伝達トルク［Ｎｍ］に、ｎはクラッチ摩擦面の数に、μは摩擦係数に、Ｐc は作動油圧［Ｐａ］に、Ｄpoはクラッチ装置を構成するピストンの外径［ｍ］に、Ｄpiは同じくピストンの内径［ｍ］に、Ｆr はピストンのリターンスプリングのセット荷重［Ｎ］に、Ｄo はクラッチ摩擦面の外径［ｍ］に、Ｄi はクラッチ摩擦面の内径［ｍ］に、それぞれ対応する。この様な式（１）の伝達トルクＴc ［Ｎｍ］と作動油圧Ｐc ［Ｐａ］との関係から、最大トルク時の伝達トルク［Ｎｍ］に対応する作動油圧［Ｐａ］として、上記必要クラッチ圧を求める事ができる。

In this equation (1), Tc is the transmission torque [Nm] of the clutch device, n is the number of clutch friction surfaces, μ is the friction coefficient, Pc is the hydraulic pressure [Pa], and Dpo is the clutch device. Pi is the piston outer diameter [m], Dpi is the piston inner diameter [m], Fr is the piston return spring set load [N], Do is the clutch friction surface outer diameter [m], and Di is the clutch This corresponds to the inner diameter [m] of the friction surface. From the relationship between the transmission torque Tc [Nm] and the hydraulic pressure Pc [Pa] in the equation (1), the required clutch pressure is set as the hydraulic pressure [Pa] corresponding to the transmission torque [Nm] at the maximum torque. You can ask for it.

  In the case of the structure having the relationship shown in FIG. 12 as described above, the maximum value of the required clutch pressure at the maximum torque is about 1.4 [MPa] (point a in FIG. 12). In such a structure, when the pressure reducing valve 38 is set to 1.4 [MPa], the hydraulic pressure of the primary line 50 adjusted to the loading pressure exceeds the maximum value (1.4 [MPa]). However, slipping (clutch plate slipping) occurs at the clutch fastening portion (power transmission portion) while preventing the hydraulic pressure larger than the maximum value from being introduced into the low speed and high speed clutches 7 and 8. You can prevent things. However, in the case of such a structure, conversely speaking, the hydraulic pressure introduced into the low speed and high speed clutches 7 and 8 is always at the maximum torque (regardless of the operation state at that time) (engine 1 At the maximum output) (adjusted) to the maximum value (1.4 [MPa]) of the required clutch pressure.

  That is, for example, even in a state where the output of the engine 1 is reduced (low torque) and high speed operation (high speed running), each of the low speed and high speed clutches 7 and 8 has a high hydraulic pressure at the maximum torque (maximum Necessary clutch pressure) is introduced. In the case of such a structure, depending on the operation state at that time, an unnecessarily high hydraulic pressure is introduced into the low speed and high speed clutches 7 and 8, and accordingly, each of the clutches 7 and 8 constituting the clutches 7 and 8. Control (for example, rotating shafts and rolling bearings constituting the low-speed and high-speed clutches 7 and 8, or an oil passage for introducing pressure oil to both the clutches 7 and 8, and a control for switching the hydraulic pressure introduction state) Valves, etc.) are loaded more than necessary. In order to withstand such a load, the structure of each of the low speed and high speed clutches 7 and 8 is increased in size, or the hydraulic pressure higher than necessary is increased. There is a possibility that the transmission efficiency of the transmission as a whole decreases.

  As a technique for controlling the hydraulic pressure introduced into the clutch device, for example, the inventions described in Patent Documents 7 and 8 are known. Among them, Patent Document 7 relates to a continuously variable transmission that can realize a geared neutral state, and a power circulation clutch (for realizing a mode including a geared neutral state) for a predetermined time after detecting that the vehicle has started. A technique for adjusting (gradually increasing) the hydraulic pressure introduced to the clutch) according to the torque input from the engine to the toroidal continuously variable transmission is described. If such a technique is adopted, the power circulation clutch can be used even when the output torque of the engine is small at the start of the vehicle and the transmission ratio of the toroidal type continuously variable transmission deviates from the GN value. By reducing the hydraulic pressure introduced to the engine, it is possible to prevent the engine from being stopped (engine stalled) by causing slippage in this power circulation clutch (half clutch state). Along with this, the vehicle can be started smoothly by gradually increasing the hydraulic pressure as the output torque of the engine increases.

  Further, Patent Document 8 relates to a starting clutch control device for a toroidal-type continuously variable transmission. When the starting clutch is engaged, the half-clutch state of the starting clutch indicates the differential pressure of the actuator that controls the tilt angle of the power roller. And a technique of controlling according to the engine torque (adjusting the shelf pressure and the half-clutch state). By adopting such a technique, it is possible to prevent excessive slippage at the starting clutch when starting the vehicle, and to reduce the shock (shock) when the clutch is completely engaged (smooth clutch Connect). However, both the technique described in Patent Document 8 and the technique described in Patent Document 7 control the half-clutch state at the start of the vehicle (control clutch slippage). The hydraulic pressure introduced into the clutch device (engagement pressure of the clutch device) is not appropriately regulated in a state other than at the time of starting, that is, for example, during traveling in the low speed mode or the high speed mode. For this reason, it is possible to prevent inconveniences (enlargement of the device, reduction of transmission efficiency, etc.) due to the hydraulic pressure introduced into the clutch device becoming higher than necessary (the fastening pressure becomes larger than necessary) as described above. is not.

Japanese Patent Laid-Open No. 10-196759 JP-A-11-108147 JP 2004-225888 A JP 2004-211836 A JP 2004-76940 A Japanese Patent Laid-Open No. 9-210191 JP 2000-249226 A JP-A-6-265001 Yoshiro Morimoto, “Introduction to CVT”, Grand Prix Publishing Co., Ltd., October 2004, p93-p95

  In view of the circumstances as described above, the continuously variable transmission according to the present invention has a structure capable of appropriately regulating the engagement pressure of a clutch device (for example, a starting clutch, a low speed clutch, a high speed clutch, etc.) according to the driving situation. It was invented to realize.

The continuously variable transmission of the present invention includes a toroidal continuously variable transmission and a clutch device (for example, a start clutch, a low speed clutch, a high speed clutch, etc.).
Of these, the toroidal continuously variable transmission includes first and second disks (for example, input and output disks), a plurality of power rollers, a plurality of support members (for example, trunnions), and an actuator. Prepare.
Of these, the first and second disks are arranged concentrically and rotatably relative to each other.
Each of the power rollers is sandwiched between the inner surfaces of the first and second disks facing each other, and transmits power (force, torque) between the first and second disks. To do.
The support members rotatably support the power rollers.
The actuator displaces the support members in the axial directions of the pivots provided at both ends thereof to change the gear ratio between the first disk and the second disk.
The clutch device is of a hydraulic type that is connected based on the introduction of hydraulic pressure (that generates a fastening pressure proportional to the hydraulic pressure when the hydraulic pressure is introduced).

In particular, the continuously variable transmission according to the present invention includes clutch hydraulic pressure adjusting means for adjusting the hydraulic pressure introduced into the clutch device in accordance with the driving situation at that time.
The clutch oil pressure adjusting means obtains (calculates) a clutch target value corresponding to the oil pressure to be introduced into the clutch device based on at least the force (torque, power) passing through the toroidal type continuously variable transmission. (Output) is determined (calculated, output) based on the first function (output) and the force (torque, power) output from at least the driving source (engine, electric motor, etc.) connected to the toroidal continuously variable transmission With a second function.
Then, a first clutch target value obtained (calculated and outputted) based on the first function and a second clutch value (calculated and outputted) obtained based on the second function. The clutch target value is compared, a larger value is set as the actual clutch target value (actual target value), and the hydraulic pressure is adjusted to this clutch target value (actual target value).

  In short, the first clutch target value set based on the force (passing torque) passing through the toroidal continuously variable transmission and the force (output torque, output) from the drive source (engine, electric motor, etc.) The second clutch target value set based on the engine torque) is compared, and a larger clutch target value is set to the actual clutch target value (actual target value). This clutch target value (actual target value) Adjust the hydraulic pressure to. Note that “set to a larger target value” means that when the second clutch target value is larger than the first clutch target value, the second clutch target value is changed to the actual clutch target value (actual target value). When the first clutch target value is larger than the second clutch target value, it means that the first clutch target value is set to the actual clutch target value. Further, when the first clutch target value and the second clutch target value are the same, they may be any (the actual target value may be set to the first clutch target value, or the second clutch target value may be set). May be set).

The “force passing through the toroidal type continuously variable transmission (passing torque)” is, for example, a pair of hydraulic chambers 36a and 36b constituting the actuator 13 as described in the section “Background Art”. This corresponds to the force (power, torque) calculated (estimated) based on the hydraulic pressure difference (differential pressure) between them (see FIG. 9). The “force (output torque, engine torque) output from the drive source (engine, electric motor, etc.)” is, for example, that of an accelerator device for adjusting the output of this drive source (engine, electric motor, etc.). What is obtained (calculated or estimated) based on the operation amount (accelerator operation amount, accelerator opening, accelerator pedal depression amount), that is, output from this drive source (or predicted to be output) Corresponding to force (power, torque).
Therefore, as described in claim 2, the actuator is of a hydraulic type, and the “passing torque” is based on a difference in hydraulic pressure (differential pressure) between a pair of hydraulic chambers provided in the actuator. (Calculate, estimate). In this case, the differential pressure can be directly associated with the first clutch target value. At the same time, the “output torque (engine torque)” is obtained (calculated or estimated) based on the operation amount of the accelerator device for adjusting the output of the drive source. In this case, the output torque can be directly associated with the second clutch target value. The “output torque (engine torque)” is not only the operation amount (accelerator operation amount, accelerator opening, accelerator pedal depression amount) but also the operation amount and the drive source (engine, electric motor, etc.). It can also be obtained (calculated, estimated, or associated with the second clutch target value) based on the rotational speed of the drive shaft (engine rotational speed).

  In any case, at least “passing torque” or “output torque (engine torque)” is used to set (calculate) the clutch target value. The “at least” means not only the “passing torque” or the “output torque (engine torque)” but also the “passing torque” or “output torque” when setting (calculating) the clutch target value. (Engine torque) ", the transmission ratio of the toroidal-type continuously variable transmission at that time (the transmission ratio between the first disk and the second disk), the speed ratio of the continuously variable transmission, the above-mentioned toroidal Other conditions such as the temperature of the lubricating oil (traction oil) circulating in the type continuously variable transmission, the temperature of the engine oil circulating in the engine, the temperature of the cooling water (oil temperature), atmospheric pressure, humidity, etc. It means not to exclude use with “torque” or “output torque (engine torque)”. For example, the setting of the clutch target value may be performed based on the “passing torque” or “output torque (engine torque)”, the speed ratio (speed ratio) (and the oil temperature, if necessary), More preferred.

In the case of implementing the continuously variable transmission of the present invention as described above, preferably a toroidal continuously variable transmission and a differential unit (for example, a gear-type differential unit) as in the invention described in claim 3. And a planetary gear type transmission) are combined through a clutch device.
Of these, the clutch device includes a first clutch (for example, a low speed clutch) and a second clutch (for example, a high speed clutch).
Of these, the first clutch (low speed clutch) is connected when realizing the first mode (for example, the low speed mode) for increasing the reduction ratio, and the second mode (for example, the high speed mode) for reducing the same. ) Shall be disconnected when realizing.
The second clutch (high speed clutch) is connected when the second mode (high speed mode) is realized, and is disconnected when the first mode (low speed mode) is realized. Shall be.
Then, during operation in the first mode (low speed mode) or the second mode (high speed mode), the first corresponding to the current traveling mode is obtained (calculated) based on the first function. One clutch target value is compared with the second clutch target value obtained (calculated) based on the second function and corresponding to the current travel mode, and a larger value is compared with the actual clutch The target value (actual target value) is set, and the hydraulic pressure is adjusted to this clutch target value (actual target value).

Further, when the invention of the continuously variable transmission described in claim 3 is carried out, the clutch device is preferably connected to the first mode (low speed mode) as in the invention described in claim 4. And switching to the second mode (high speed mode), one of the first clutch (low speed clutch) and the second clutch (high speed clutch) is connected so far. It is assumed that after the clutch that has not been connected is connected and the clutch that has been connected by the other clutch is disconnected, the time during which both the clutches are simultaneously connected is set.
At the time of mode switching between the first mode (low speed mode) and the second mode (high speed mode) (during mode switching), for example, the mode switch has not been performed until then. From the start of the clutch connection until the other clutch connected until it is disconnected (until it starts to disconnect) (at least while both the first and second clutches are connected simultaneously) Based on the second function, a target value corresponding to the current driving mode and a target value corresponding to the driving mode to be realized next are obtained (calculated), and a larger value of these target values is obtained. Is set as an actual clutch target value (actual target value), and the hydraulic pressure (hydraulic pressure introduced into at least one clutch) is adjusted to the clutch target value (actual target value).
In addition, when the target value is set based on the second function before the mode switching is started and the oil pressure is adjusted to the target value before the mode switching is started according to the operation status at that time, the mode switching is performed. Even during the time (mode switching), the target value is set based on the second function as it is, and the hydraulic pressure (hydraulic pressure introduced into at least one clutch) is adjusted to the target value.

According to the continuously variable transmission of the present invention configured as described above, the engagement pressure of a clutch device (for example, a start clutch, a low speed clutch, a high speed clutch, etc.) can be appropriately regulated according to the driving situation.
That is, the clutch hydraulic pressure adjusting means for adjusting the hydraulic pressure to be introduced into the clutch device sets the clutch target value corresponding to the hydraulic pressure to be introduced into the clutch device to the force passing through the toroidal type continuously variable transmission at that time. (Passing torque, differential pressure corresponding to passing torque) and force output from the driving source (engine, electric motor, etc.) connected to this toroidal continuously variable transmission (output torque, accelerator operation amount corresponding to output torque) ) And each. A large target value is set as an actual clutch target value (actual target value), and the hydraulic pressure introduced into the clutch device is adjusted to the actual target value.

  Thus, in order to set the clutch target value based on the state quantities of both “passing torque (differential pressure)” and “output torque (accelerator operation amount)”, the engagement pressure of the clutch device is always set at that time. Appropriate for the driving situation. For example, in a state where the “passing torque (differential pressure)” or “output torque (accelerator operation amount)” is large, the engagement pressure of the clutch device is increased and slipping occurs in the clutch engagement portion (power transmission portion). You can prevent things. On the other hand, in the state where the “passing torque (differential pressure)” or “output torque (accelerator operation amount)” is small, the engagement pressure of the clutch device is reduced (in a range where no slip occurs), and this engagement pressure is reduced. It can prevent becoming larger than necessary. For this reason, regardless of the driving situation (in any driving situation, the “passing torque (differential pressure)” or the “output torque (accelerator operation amount)” increases or decreases), the clutch engagement portion ( It is possible to prevent slippage in the power transmission part). Along with this, the clutch device can be made compact, and transmission efficiency can be improved.

  Moreover, the setting (calculation) of the clutch target value is not performed based on only one value of “passing torque (differential pressure)” and “output torque (accelerator operation amount)” (both values are set). Therefore, it is possible to make the setting of the target value more suitable for the driving situation while reliably preventing slippage at the clutch fastening portion (power transmission portion). In other words, the current driving situation is either “passing torque (differential pressure)” or “output torque (accelerator operation amount)”, such as during sudden acceleration or sudden deceleration of power based on engine braking. Even in such a situation that it is difficult to quickly appear as a change, the engagement pressure can be adjusted based on a value (a large clutch target value) in which the change quickly appears. For this reason, this fastening pressure can be made more suitable for the driving situation, and it is possible to surely prevent the clutch fastening part (power transmission part) from slipping.

  In the case of the invention described in claim 4, during the mode switching, the clutch target value is not obtained (calculated) based on the first function, that is, “passing torque (differential pressure)”. {During mode switching, it is obtained (calculated) based on the second function, that is, "output torque (accelerator operation amount)"}. For this reason, even during mode switching (even when the first and second clutches are simultaneously connected), the engagement pressure of the first and second clutches can be adjusted to an appropriate value in accordance with the driving situation at that time. . That is, with the first and second clutches connected at the same time, the passing torque (differential pressure) of the toroidal continuously variable transmission is output from the drive source (engine, electric motor, etc.) at that time. Does not correspond to force (power, torque) (becomes irrelevant). For example, when the first and second clutches are simultaneously connected in a state where the transmission ratio of the toroidal type continuously variable transmission completely matches the mode switching point, the passing torque (differential pressure) is 0. become.

  In such a case, if the clutch target value is adjusted based on only the passing torque (differential pressure) (only the first function) as it is, during the mode switching or immediately after the completion (the other clutch connected so far) The engagement pressure (or clutch target value) immediately after disconnection of the clutch is excessively small (becomes smaller than the required value at that time), and the clutch engagement part (power transmission part) may slip. There is. On the other hand, in the case of the invention described in claim 4, during the mode switching as described above, the clutch target value is obtained based on the second function, that is, “output torque (accelerator operation amount)”. Therefore, even if both the first and second clutches are connected at the same time, an appropriate value corresponding to the force (power, torque) output from the drive source (engine, electric motor, etc.) at that time Fastening pressure can be maintained. In addition, when the mode is switched, it is possible to prevent a decrease (insufficiency) in the fastening pressure associated with reversing the direction of the torque (passing torque) passing through the toroidal type continuously variable transmission (when the differential pressure becomes zero). For this reason, the unnecessary fluctuation | variation of this fastening pressure can also be reduced (a fastening pressure does not change a lot), and the torque shift accompanying the fluctuation | variation of this fastening pressure can also be aimed at.

  Further, in the case of the invention described in claim 4, during the mode switching, based on the second function, the clutch target value corresponding to the current travel mode and the travel mode to be realized next is set. Ask. Then, a larger value is set as an actual clutch target value (actual target value), and the hydraulic pressure is adjusted to the clutch target value (actual target value). For this reason, even when the required clutch pressure is different before and after the mode switching, it is possible to reliably prevent the engagement pressures of the first and second clutches from being insufficient from the start of the mode switching to immediately after the completion of the mode switching.

  1 to 7 show an example of an embodiment of the present invention. The feature of this example is that the hydraulic pressure introduced into the clutch device 6 is adjusted (clutch hydraulic pressure) in order to secure the fastening pressure of the clutch device 6 to be connected (low speed and high speed clutches 7 and 8). In addition to devising the structure of the adjusting means) and the adjustment procedure, the hydraulic pressure to be introduced into the pressing device 14 is adjusted so that an appropriate pressing force is applied at the traction portion (rolling contact portion) that transmits power. The structure of the part to be done is also devised. Since the structure and operation of the other parts are the same as those of the conventional structure shown in FIGS. 8 to 9, the overlapping description will be omitted or simplified, and the following description will focus on the characteristic parts of this example. In the case of this example, the relationship between the speed ratio (speedup ratio) of the continuously variable transmission as a whole and the speed ratio (speedup ratio) of the toroidal-type continuously variable transmission 4 is shown, for example, in FIG. It is set like this. Such a setting can be performed, for example, by regulating the reduction ratio of the planetary gear type transmission 5 or the like, the gear ratio of the transmission gear, and the like.

  The configurations of the hydraulic circuits shown in FIGS. 2 and 3 of this example are different from each other in that a differential pressure take-out valve 37 (see FIG. 3) is provided. That is, in the case of the hydraulic circuit of FIG. 3, a differential pressure take-out valve 37 similar to that of the hydraulic circuit shown in FIG. 8 is provided, whereas in the case of the hydraulic circuit of FIG. Such a differential pressure extraction valve 37 is not provided (omitted). However, in the case of the hydraulic circuit in FIG. 3, the pilot chamber 43 of the differential pressure take-out valve 37 communicates with the oil reservoir 28, and an oil passage 44 a between the differential pressure take-out valve 37 and the pressing force adjustment valve 29, The differential pressure take-out valve 37 is prevented from functioning (for example, the hydraulic pressure corresponding to the differential pressure is not introduced into the pressing force adjusting valve 29), for example, by closing 44b with a blind plug. That is, the hydraulic circuit in FIG. 3 is substantially the same as the hydraulic circuit in FIG. 2 in which the differential pressure take-out valve 37 is omitted. Therefore, the following description will be made without distinguishing the structure of FIG. 2 from the structure of FIG. 3 (the following description corresponds to the structure of both FIG. 2 and FIG. 3).

  In the case of the conventional structure shown in FIGS. 8 to 9, the switching state of the low speed and high speed clutches 7 and 8 (switching between the low speed mode and the high speed mode) is changed to one shift electromagnetic. This is performed by the valve 20 (FIGS. 8 to 9), but in the case of this example, it is performed by the low-speed clutch and high-speed clutch electromagnetic valves 45 and 46 (two electromagnetic valves 45 and 46). At the same time, in this example, the pressure oil in the primary line 50 that is adjusted (pressure-regulated) by the pressing force adjusting valve 29 as in the conventional structure shown in FIGS. The configuration (see FIGS. 8 to 9) that is introduced into each of the clutches 7 and 8 is not adopted. That is, in the case of this example, as will be described in detail later, a clutch pump 53 is provided separately from the oil pump 27a that feeds the pressure oil to the primary line 50, and the low speed, Pressure oil is sent to the clutches 7 and 8 for high speed. In short, the pressure oil introduced into the low-speed and high-speed clutches 7 and 8 and the pressure oil introduced into the pressing device 14 through the primary line 50 are supplied by different systems (low-speed and high-speed). The pressure oil introduced into the clutches 7 and 8 and the pressure oil introduced into the pressing device 14 can be adjusted separately).

  In the case of this example, the electromagnetic valve 19 for correcting the transmission ratio of the toroidal-type continuously variable transmission 4 as in the conventional structure shown in FIGS. The correction control valves 24a and 24b and the forward / reverse switching valve 47 (see FIG. 9) are not provided (omitted). However, a structure for correcting such a gear ratio can be provided as necessary. Further, in the case of the present example, a pair of actuators 13 constituting the pressing force adjusting valve 29 for adjusting the hydraulic pressure introduced into the pressing device 14 as in the conventional structure shown in FIGS. The configuration (see FIGS. 8 to 9) that directly introduces the hydraulic pressure difference (differential pressure) between the hydraulic chambers 36 a and 36 b is not adopted. In other words, in the case of this example, the differential pressure is detected by a pair of hydraulic sensors 39a and 39b (39 in FIG. 1) provided in the hydraulic chambers 36a and 36b. Based on the “passing torque”), the hydraulic pressure to be introduced into the pressing device 14 (the pressing force generated by the pressing device 14) is supplied to the controller 16, the line pressure control electromagnetic switching valve 18, and the pressing force adjustment valve 29. I use it and adjust it.

  However, if only the adjustment based on the differential pressure is performed in this manner, the pressing force generated by the pressing device 14 may be excessive or small at the time of mode switching, for example. In addition, even when the mode is not switched (low speed mode or high speed mode), the sensor for detecting the differential pressure, the switching valve, etc., when the power suddenly fluctuates during sudden acceleration (when the accelerator pedal is depressed suddenly) With the response delay, the pressing force generated by the pressing device 14 may be insufficient. Therefore, in the case of the present example, the toroidal type continuously variable transmission is applied to the hydraulic pressure introduced into the pressing device 14 (the pressing force generated by the pressing device 14) in addition to the differential pressure (corresponding to “passing torque”). Adjustment is made based on the “output torque” of the engine 1 connected to the machine 4. More specifically, the operation amount (accelerator operation amount, accelerator opening degree, accelerator pedal depression amount) of the accelerator device for adjusting the output of the engine 1 corresponding to the “output torque”, and the engine 1 The hydraulic pressure introduced into the pressing device 14 can be adjusted based on the rotational speed (engine rotational speed) of the drive shaft (crankshaft). For example, Japanese Patent Application No. 2008-14722 (filed on Jan. 25, 2008, serial number: NSK071473) regarding the structure of the part for adjusting the hydraulic pressure to be introduced into the pressing device 14 and the adjustment procedure. And is not directly related to the gist of the present invention, and a detailed description thereof will be omitted.

  In the case of this example, the hydraulic pressure is introduced into the low speed and high speed clutches 7 and 8 in a separate system from the hydraulic pressure introduced into the pressing device 14 (hydraulic pressure of the primary line 50) adjusted as described above. That is, in the case of this example, as described above, the clutch pump 53 is provided separately from the oil pump 27a that sends the pressure oil to the primary line 50, and the pressure oil discharged from the clutch pump 53 is supplied to the manual hydraulic pressure. The low-speed and high-speed clutches 7 and 8 are fed through the switching valve 31, the pressure reducing valve 38a, and the low-speed clutch and high-speed clutch solenoid valves 45 and 46, respectively. In the case of this example, the clutch hydraulic pressure adjusting means described in the claims is provided by the clutch pump 53, the low-speed clutch electromagnetic valves 45 and 46, and the controller 16. It is composed.

  In the case of this example, mode switching between the low speed mode and the high speed mode is performed as follows. That is, when the mode is switched from the low speed mode to the high speed mode while traveling in the low speed mode (only the low speed clutch 7 is connected), as shown in FIG. In order to connect (ON) the high-speed clutch 8 that did not exist, a command (control signal) to connect the high-speed clutch 8 is issued from the controller 16 to the high-speed clutch solenoid valve 46. Thereafter, in order to disconnect (turn off) the low-speed clutch 7 that has been connected so far, the controller 16 instructs the low-speed clutch solenoid valve 45 to disconnect the low-speed clutch 7 ( Control signal).

  On the other hand, when the mode is switched from the high speed mode to the low speed mode while traveling in the high speed mode (only the high speed clutch 8 is connected), as shown in FIG. In order to connect (ON) the low-speed clutch 7 that has not existed, a command (control signal) to connect the low-speed clutch 7 is issued from the controller 16 to the low-speed clutch electromagnetic valve 45. Thereafter, in order to disconnect (turn off) the high-speed clutch 8 that has been connected so far, the controller 16 instructs the high-speed clutch solenoid valve 46 to disconnect the high-speed clutch 8 ( Control signal).

  In the case of this example, during traveling in the low speed mode or the high speed mode, the hydraulic pressure to be introduced into the low speed and high speed clutches 7 and 8 is adjusted according to the driving situation at that time. That is, the hydraulic pressure introduced into the low speed and high speed clutches 7 and 8 (engagement pressure of the low speed and high speed clutches 7 and 8) is passed through the toroidal continuously variable transmission 4 (passing torque), In addition, the torque is adjusted based on the torque (output torque) output from the engine 1 connected to the toroidal-type continuously variable transmission 4. For this reason, in this example, a control signal (command signal) is output from the controller 16 to the solenoid valves 45 and 46, which are solenoid valves (solenoid valves). (Pulse width modulation output) (controlled by PWM method), and these low-speed clutch and high-speed clutch solenoid valves 45 and 46 are used as proportional control valves. That is, the opening and closing amounts of the low-speed clutch and high-speed clutch solenoid valves 45 and 46 are adjusted by PWM control, and the hydraulic pressure introduced into the low-speed and high-speed clutches 7 and 8 is output from the controller 16. The value can be adjusted (variable) according to the signal (pulse width).

  At the same time, the controller 16 obtains (estimates or calculates) the magnitude of the torque (passing torque) passing through the toroidal continuously variable transmission 4, which is obtained from the differential pressure, and the toroidal type. Based on the speed ratio of the continuously variable transmission 4 (speed ratio to the continuously variable transmission), the hydraulic pressure to be introduced into the low speed and high speed clutches 7 and 8 (to the low speed and high speed clutches 7 and 8). A function (first function) for setting (calculating) a clutch target value corresponding to the engagement pressure to be generated is provided. The speed ratio of the toroidal-type continuously variable transmission 4 can be detected by the rotational speed sensors 40 and 41 on the input side and output side (as the ratio of the rotational speeds of the disks 10 and 11 on the input side and output side), It can also be obtained by measuring the inclination angle (rotation angle about the pivot axis) of the support member (trunnion) that supports each power roller 12. Further, when it is necessary to use the speed ratio of the continuously variable transmission, the speed ratio of the toroidal continuously variable transmission 4 and the current travel mode can be obtained.

  Further, the clutch target value is obtained in advance by experiment or calculation as a correlation between the clutch target value, the differential pressure (passing torque) and the speed ratio (speed ratio), and the memory of the controller 16 is obtained. Are stored as a map, a calculation formula, or a diagram. As such correlation, for example, the above-described equation (1) can be used (the passing torque corresponds to the transmission torque Tc [Nm] and the clutch target value corresponds to the operating oil pressure Pc [Pa]). FIG. 5 is a diagram showing the correlation between the clutch target value (required clutch pressure) at the maximum torque and the speed ratio of the entire continuously variable transmission, which is obtained by using this equation (1). FIG. 5 shows the clutch target value (required clutch pressure) when the safety factor is 1.0 and when it is 1.1. Which one is used is determined according to the use situation or the like.

  In addition to the above formula (1) and the diagram of FIG. 5, the differential pressure (passing torque) obtained by, for example, experiments and calculations, and the low speed and high speed clutches 7 and 8 are introduced. It is possible to use a MAP or a diagram representing the relationship with the hydraulic pressure (required clutch pressure) to be used. In this case, a common mode can be used for the low-speed mode and the high-speed mode, and one corresponding to the low-speed mode (for example, a low-speed mode MAP or a diagram) and one corresponding to the high-speed mode (for example, the high-speed mode). Separate MAP and diagram) can be used. In any case, the controller 16 corresponds to the differential pressure (passing torque) and the gear ratio (tilt angle) at that time based on such a map, calculation formula, diagram, or the like. In addition to setting the clutch target value, a signal corresponding to the clutch target value is output to each of the low-speed clutch solenoid valve 45 and 46 (PWM output, pulse width modulation) in order to adjust the clutch target value. Output. Based on the opening / closing (switching) of the low-speed clutch and high-speed clutch solenoid valves 45 and 46 based on this output, the hydraulic pressure introduced into the hydraulic chambers 52a and 52b of the low-speed and high-speed clutches 7 and 8 is determined. By adjusting to the clutch target value, the engagement pressures of the low speed and high speed clutches 7 and 8 are appropriately regulated.

  However, if the target value is set based only on the differential pressure (passing torque) in this way, for example, when the mode is switched, the engagement pressures of the low speed and high speed clutches 7 and 8 become excessive, or There is a possibility of becoming too small. A sensor that detects the above differential pressure (passing torque) even when the mode is not changed (low speed mode or high speed mode), or when the power suddenly fluctuates during sudden acceleration (when the accelerator pedal is depressed suddenly). With the response delay of the hydraulic sensors 39, 39a, 39b), etc., there is a possibility that the fastening pressures of the low speed and high speed clutches 7, 8 are insufficient. Therefore, in the case of this example, the clutch target value is set to the force (output torque, engine torque) output from the engine 1 connected to the toroidal continuously variable transmission 4 in addition to the differential pressure (passing torque). It is made to be requested based on. More specifically, the clutch target value, the operation amount of the accelerator device for adjusting the output of the engine 1 (accelerator operation amount, accelerator opening, accelerator pedal depression amount), and the drive shaft of the engine 1 It is determined based on the rotational speed of the (crankshaft) (engine rotational speed).

  In short, in the case of this example, the low-speed and high-speed clutches 7 and 8 necessary for setting the hydraulic pressure to be introduced into the low-speed and high-speed clutches 7 and 8 are set in the controller 16. In addition to the function of obtaining the magnitude of transmitted power (force, torque) based on the differential pressure, the operation amount of the accelerator device (accelerator opening) and the rotational speed of the drive shaft of the engine 1 (engine rotational speed) ) And the function requested based on. And, if necessary (for example, when the power changes suddenly during mode switching or sudden acceleration, etc.), based on the manipulated variable (accelerator opening) and rotational speed (engine rotational speed), The target value of the hydraulic pressure (clutch target value) to be introduced into each of the high speed clutches 7 and 8 is set. The operation speed and operation amount of the accelerator device can be detected by an accelerator sensor 48 for detecting the operation amount of the accelerator pedal (stepping amount, stepping amount, and opening amount). The rotational speed of the engine 1 can be detected by a rotational speed sensor (or tachometer signal) (not shown) for detecting the rotational speed of the drive shaft (crankshaft) of the engine 1 (input side rotational speed sensor). 40 can also be used).

In any case, the controller 16 is output from the engine 1 based on the operation amount of the accelerator device (accelerator opening) and the rotational speed of the drive shaft of the engine 1 (engine rotational speed) (or through). Is capable of calculating (estimating) the magnitude of force (output torque, engine torque) that is predicted to be output. For this purpose, the memory of the controller 16 stores the characteristics of the engine 1 mounted on the vehicle, for example, the characteristics of the engine torque [Nm] corresponding to the accelerator opening [%] and the engine speed [min ⁻¹ ]. For example, it is stored (programmed) as a map, a calculation formula, or a diagram. Then, the controller 16 calculates (estimates) the engine torque corresponding to the accelerator opening and the engine speed at that time based on the engine characteristics as described above. In addition, when communication is possible between the engine controller 49 for controlling the engine 1 and the controller 16 using, for example, a CAN (Controller Area Network) or the like, the engine controller 49 sets the accelerator opening. Corresponding engine torque data can also be obtained. However, in addition to the possibility of causing a time delay during communication, such a means cannot be adopted in the case of a vehicle that cannot communicate (or has no communication means). For this reason, it is more preferable to calculate (estimate) the engine torque from the accelerator opening and the engine speed as described above using a map, a calculation formula, a diagram, or the like.

  When the output torque (engine torque) is obtained as described above, the controller 16 uses the controller 16 based on the output torque (engine torque) and the gear ratio of the toroidal-type continuously variable transmission 4 to reduce the speed. Then, a clutch target value corresponding to the hydraulic pressure to be introduced into each of the high speed clutches 7 and 8 (hydraulic pressure corresponding to the engagement pressure to be generated in each of the low speed and high speed clutches 7 and 8) is set (calculated). Even when the clutch target value is set based on the output torque (engine torque) and the gear ratio, the correlation between the clutch target value, the output torque (engine torque) and the gear ratio is The memory of the controller 16 is stored as a MAP, a calculation formula, or a diagram, and is set (calculated) using such a MAP, a calculation formula, a diagram, or the like. As such correlation, for example, the above-described equation (1) can be used (the output torque corresponds to the transmission torque Tc [Nm] and the clutch target value corresponds to the operating oil pressure Pc [Pa]). Further, the correlation between the clutch target value (required clutch pressure) at the maximum torque and the speed ratio of the entire continuously variable transmission, obtained by using this equation (1), is as shown in FIG. . In addition to the above formula (1) and the diagram of FIG. 5, for example, the output torque (accelerator opening degree, engine rotation speed) and the low speed and high speed clutches obtained by experiments and calculations, for example. It is possible to use a MAP or a diagram representing the relationship with the hydraulic pressure to be introduced into 7 and 8. In this case, a common mode can be used for the low-speed mode and the high-speed mode, and one corresponding to the low-speed mode (for example, a low-speed mode MAP or a diagram) and one corresponding to the high-speed mode (for example, the high-speed mode). Separate MAP and diagram) can be used.

  Further, for example, the engine torque (output torque) used in the MAP, calculation formula, diagram, etc. may be calculated (created) in correspondence with the torque (input torque) input to the toroidal type continuously variable transmission 4. preferable. In this case, in order to calculate the torque input to the toroidal-type continuously variable transmission 4 from the engine torque, a member (torque passes) provided between the engine 1 and the toroidal-type continuously variable transmission 4. The efficiency of the gears to be This efficiency varies depending on the gear ratio of the toroidal-type continuously variable transmission 4 and the travel mode (low speed mode / high speed mode), so it is difficult to calculate strictly. For this reason, the MAP and diagram as described above are obtained, for example, by experiments (created using experimental values). If the efficiency between the engine 1 and the toroidal-type continuously variable transmission 4 can be obtained, a calculation formula using this efficiency is used instead of the MAP or diagram as described above. You can also do it.

  If the clutch target value corresponding to the output torque (engine torque) and the gear ratio at that time is set using the diagram, calculation formula, MAP, or the like as described above, the controller 16 In order to adjust to this clutch target value, signals corresponding to the clutch target value are output {PWM output, pulse width modulation output} to the electromagnetic valves 45 and 46 for the low speed clutch and the high speed clutch. Based on the opening / closing (switching) of the low-speed clutch and high-speed clutch solenoid valves 45 and 46 based on this output, the hydraulic pressure introduced into the hydraulic chambers 52a and 52b of the low-speed and high-speed clutches 7 and 8 is determined. By adjusting to the clutch target value, the engagement pressures of the low speed and high speed clutches 7 and 8 are appropriately regulated. If necessary, the clutch target value, that is, the hydraulic pressure actually introduced into the hydraulic chambers 52a and 52b of the low speed and high speed clutches 7 and 8, as well as the low speed clutch and high speed. The opening / closing amounts (PWM output amounts) of the clutch solenoid valves 45 and 46 are corrected in accordance with the oil temperature at that time {the temperature of the lubricating oil (traction oil) circulating in the toroidal continuously variable transmission 4}. Things are preferable.

  In this case, for example, the relationship between the clutch target value obtained for each oil temperature and the opening / closing amounts of the solenoid valves 45 and 46 for the low speed clutch and the high speed clutch is used according to the oil temperature at that time. Adjust (correct) the open / close amount. With this configuration, the hydraulic pressure (actual engagement pressure) actually introduced into the hydraulic chambers 52a and 52b of the low-speed and high-speed clutches 7 and 8 is determined by the friction coefficient and the temperature of each component at that time. It can be regulated to a value (more optimal value) according to characteristics (for example, elastic deformation amount). Moreover, the target hydraulic pressure can be introduced regardless of the viscosity change of the lubricating oil. Even when the clutch target value is set based on the above-described differential pressure (passing torque), the opening / closing amounts (PWM output) of the low-speed clutch and high-speed clutch solenoid valves corresponding to the oil temperature at that time. Ability (adjustment) can be adjusted (corrected).

  As described above, in the case of this example, the adjustment of the hydraulic pressure introduced into the pressing device 14 includes the second function {the operation amount of the accelerator device (accelerator opening) and the second function in addition to the first function (differential pressure). And the rotation speed of the drive shaft of the engine 1 (engine rotation speed). The controller 16 is provided with a function for selecting at which clutch target value the hydraulic pressure is adjusted in accordance with the operation state at that time. Specifically, during operation in the low speed mode and the high speed mode, the target value (first clutch target value) set based on the first function and the second function are set. Target value (second clutch target value), set the target value with the larger value as the actual target value (actual target value), and adjust the hydraulic pressure to this target value (actual target value) It has a function to do. In addition, at the time of mode switching between the low speed mode and the high speed mode, that is, to start mode switching, one clutch 7 (8) that has not been connected until then is started {one side After a command (control signal) is issued from the controller 16 to connect the clutch 7 (8) to the clutch switching valve 45 (46) for connecting the clutch 7 (8) of the clutch} Until the connection of the other clutch 8 (7) which has been disconnected is disconnected {the clutch 8 (7) is disconnected from the clutch switching valve 46 (45) for connecting the other clutch 8 (7). Until a command (control signal) is issued from the controller 16}, based on the second function only, the target value (second pressure) of the oil pressure to be introduced into each of the low speed and high speed clutches 7, 8 Set the clutch target value) You have to have the ability to adjust the hydraulic pressure.

The function (clutch pressure control) provided in the controller 16 as described above will be described with reference to the flowchart of FIG. The work shown in this flowchart is repeatedly (automatically) performed when the shift lever is operated in the traveling state (D, L, R range), for example. On the other hand, when the shift lever is operated in the non-running state (N, P range), it is not performed.
First, in step 1, the controller 16 determines whether or not the current traveling mode is the low speed mode. This determination is made, for example, by determining the switching state (energized state) of the high-speed clutch and low-speed clutch solenoid valves 45 and 46 and the connection / disconnection state of the low-speed and high-speed clutches 7 and 8 at that time. Do it by things. If it is determined in step 1 that the current travel mode is the low speed mode, the process proceeds to step 2. In step 2, it is determined whether or not the mode is currently being switched from the low speed mode to the high speed mode. In this determination, for example, in order to connect the low speed clutch 7, the low speed clutch solenoid valve 45 is switched to a state in which pressure oil is introduced into the low speed clutch 7, and the high speed clutch 8. The high-speed clutch solenoid valve 46 is also switched to a state where pressure oil is introduced into the high-speed clutch 8 (a command for switching is issued). Do.

In such step 2, the mode is not currently switched from the low speed mode to the high speed mode, that is, the operation is being performed in the low speed mode (a command to connect the clutch only to the electromagnetic valve 45 for low speed clutch is issued). If it is determined, the process proceeds to step 3. In Step 3 to Step 8 (excluding Step 7), the hydraulic pressure to be introduced into the low speed clutch 7 is set based on both the first and second functions. More specifically, a clutch target value (second clutch target value A _L ) set based on the second function (output torque) and a clutch set based on the first function (passing torque) The target value (first clutch target value B _L ) is compared, and a larger target value is set as an actual clutch target value (actual target value). For this purpose, first, in step 3, the clutch target value (second clutch target value A _L ) is calculated based on the second function. That is, in this step 3, based on the output torque (accelerator opening degree, engine speed) at that time and the gear ratio of the toroidal-type continuously variable transmission 4 (speed ratio of the continuously variable transmission), the clutch target A value (second clutch target value A _L ) is calculated. In Step 3, since the vehicle is operating in the low speed mode, the second clutch target value _AL is calculated using, for example, the low speed mode MAP.

Step 3 Thus, by using the MAP for the low-speed mode, corresponding to the output torque at the time the speed change ratio (speed ratio), if the calculated the second clutch target value A _L, the following step In step 4, the clutch target value (first clutch target value B _L ) is calculated based on the first function. That is, in this step 4, based on the passing torque (differential pressure) at that time and the speed ratio of the toroidal continuously variable transmission 4 (speed ratio of the continuously variable transmission), the clutch target value (first value) The clutch target value B _L ) is calculated. In Step 4, since the vehicle is operating in the low speed mode, the first clutch target value _BL is calculated using, for example, the low speed mode MAP.

As described above, in step 3, the second clutch target value A _L is calculated based on the second function, and in step 4, the first clutch target value B _L is calculated based on the first function. If so, in the following step 5, the first clutch target value B _L is compared with the second clutch target value A _L. Specifically, it is determined whether or not the second clutch target value A _L is equal to or greater than the first clutch target value B _L (A _L ≧ B _L ). If it is determined in step 5 that the second clutch target value A _L is greater than or equal to the first clutch target value B _L (A _L ≧ B _L ), the process proceeds to step 6, The second clutch target value _AL is set to the actual target value. Then, the process proceeds to step 7, in order to adjust the hydraulic pressure to the second clutch target value A _L, to adjust (PWM control) of the opening and closing states of the solenoid valve 45 for the low-speed clutch. On the other hand, in the step 5, the second clutch target value A _L is not greater than or equal to the first clutch target value B _L , that is, the second clutch target value A _L is the first clutch target value B _L. If it is determined that it is smaller than (A _L <B _L ), the process proceeds to step 8, in which the first clutch target value B _L is set to the actual target value. Then, the process proceeds to step 7, and the open / close state of the low-speed clutch electromagnetic valve 45 is adjusted (PWM control) in order to adjust the hydraulic pressure to the first clutch target value _BL .

On the other hand, in step 2, the mode is currently being switched from the low speed mode to the high speed mode, that is, not only the low speed clutch electromagnetic valve 45 but also the high speed clutch electromagnetic valve 46 is connected to the clutch. If it is determined that a command has been issued (both low speed and high speed clutches 7 and 8 are simultaneously connected, or a command for that is issued), the routine proceeds to step 9. In Step 9 to Step 13, the target value (clutch target value) of the hydraulic pressure to be introduced into at least the high speed clutch 8 (the clutch for realizing the high speed mode that is the next travel mode to be realized) is set to the second function. Set based on. For this purpose, first, in step 9, the second clutch target value A _{L is} determined based on the output torque (engine speed, accelerator opening) at that time and the gear ratio of the toroidal-type continuously variable transmission 4. Is calculated. In the step 9, the current drive mode, i.e., in order to calculate the clutch target value A _L corresponding to low-speed mode, for example, the calculation using the MAP for the low-speed mode performs. Further, in the following step 10, using the MAP for high-speed mode, and calculates a clutch target value A _H for high-speed mode.

Performs calculation of the second clutch target value A _L corresponding to low-speed mode is the current mode based on the second function in step 9 as described above, based on the same second function in step 10 If the second clutch target value A _H corresponding to the high speed mode, which is the next mode to be realized, is calculated, in the subsequent step 11, the second both clutch target values A _L and A _H are compared. To do. Specifically, it is determined whether or not the second clutch target value A _L corresponding to the low speed mode is equal to or greater than the second clutch target value A _H corresponding to the high speed mode (A _L ≧ A _H ). If it is determined in step 11 that the second clutch target value A _L corresponding to the low speed mode is equal to or greater than the second clutch target value A _H corresponding to the high speed mode (A _L ≧ A _H ). proceeds to step 12, sets the second clutch target value a _L corresponding to low-speed mode of this actual target value. Then, the process proceeds to step 7 of the foregoing, in order to adjust the hydraulic pressure to the second clutch target value A _L corresponding to the low-speed mode, to adjust the opening and closing state of at least the high speed clutch solenoid valve 46 (PWM control). On the other hand, in step 11, the second clutch target value A _L corresponding to the low speed mode is not equal to or greater than the second clutch target value A _H corresponding to the high speed mode, that is, the second clutch target value A _H corresponding to the low speed mode. When it is determined that the clutch target value A _L is smaller than the second clutch target value A _H corresponding to the high speed mode (A _L <A _H ), the process proceeds to step 13 and corresponds to the high speed mode. a second clutch target value a _H is set to the actual target value. Then, the process proceeds to step 7, in order to adjust the hydraulic pressure to the second clutch target value A _H corresponding to the high-speed mode, to adjust the opening and closing state of at least the high speed clutch solenoid valve 46 (PWM control).

On the other hand, if it is determined in step 1 that the current travel mode is not the low speed mode, that is, the current travel mode is the high speed mode, the process proceeds to step 14. Steps 14 to 24 are the same as steps 2 to 6 described above except that the low speed mode and the high speed mode are different {low speed (L) and high speed (H) are reversed}. It is the same as 8-13. That is, out of the above steps 14 to 24, in steps 14 to 19, the second clutch target value A _H and the first clutch target value B _H are determined based on the determination that the vehicle is operating in the high speed mode. Is set as the actual clutch target value (actual target value). Also in step 14,20～24, from the high-speed mode based on a determination of that the performed mode switching to the low-speed mode, the second corresponding to the second clutch target value A _L and fast modes corresponding to low-speed mode target value of the actual clutch target value of a larger value of the clutch target value a _H is set as (actual target value). In either case, the process proceeds to step 7, and the open / close states of the low-speed clutch and high-speed clutch solenoid valves 45 and 46 are adjusted (PWM control) to adjust the hydraulic pressure to the target value set in this way. )

In the case of this example configured as described above, the engagement pressures of the low-speed and high-speed clutches 7 and 8 constituting the clutch device 6 can be appropriately regulated according to the operating conditions.
That is, the controller 16 determines the clutch target value corresponding to the hydraulic pressure to be introduced into each of the low speed and high speed clutches 7 and 8 as the force (passing torque) passing through the toroidal type continuously variable transmission 4 at that time. ), The first target value B _L (B _H ) obtained based on the differential pressure, the accelerator operation amount corresponding to the force (output torque) output from the engine 1 as the drive source, and the engine speed. {set as the actual clutch target value larger target value (actual target value)} where the second target value a _L (a _H) and set by obtained based on. Then, according to the clutch target value (actual target value), the low-speed and high-speed clutches 7 are controlled by adjusting (PWM control) the open / closed states of the low-speed clutch and high-speed clutch solenoid valves 45 and 46. , 8 is adjusted to this clutch target value (actual target value). In this way, the clutch target value is set based on the state quantities of both “passing torque (differential pressure)” and “output torque (accelerator operation amount, engine speed)”. The engagement pressures of the clutches 7 and 8 can be made appropriate according to the operation state at that time. For this reason, regardless of the driving situation (in any driving situation), while preventing slippage at the clutch fastening portions (power transmission portions) of the clutches 7 and 8 for low speeds and high speeds, Each of the high-speed clutches 7 and 8 (the entire system of the clutch device 6) can be made compact, and transmission efficiency can be improved.

  In particular, in this example, the clutch target value is set (calculated) to only one value of “passing torque (differential pressure)” and “output torque (accelerator operation amount, engine speed)”. Since it is not performed based on (both values are used), it is possible to make the setting of the clutch target value more suitable for the driving situation while reliably preventing slippage at the clutch engagement portion (power transmission portion). . That is, the current driving situation is “passing torque (differential pressure)” and “output torque (accelerator operation amount, engine speed)”, such as during sudden acceleration or sudden deceleration of power based on engine braking. Even in a situation in which it is difficult to quickly appear as a change in any of these values, the engagement pressure can be adjusted based on a value (a large clutch target value) in which the change appears quickly. For this reason, this fastening pressure can be made more suitable for the driving situation, and it is possible to surely prevent the clutch fastening part (power transmission part) from slipping.

  In addition, in this example, during mode switching, the clutch target value is obtained (calculated) based only on the second function, that is, only “output torque (accelerator operation amount, engine speed)”. For this reason, even when the mode is switched (even when both the low speed and high speed clutches 7 and 8 are simultaneously connected), the engagement pressure can be adjusted to an appropriate value in accordance with the driving situation at that time. For example, FIG. 6 schematically shows changes in the state quantities of the respective parts when the mode is switched from the low speed mode to the high speed mode during acceleration by depressing the accelerator pedal. FIG. 7 schematically shows changes in the state quantities of the respective parts when the mode is switched from the high speed mode to the low speed mode while the accelerator pedal is released and the vehicle is decelerating. Also, in these lowermost clutch control pressure diagrams of FIGS. 6 and 7, the change in the engagement pressure (control pressure) when only the second function is used during mode switching (in this example) is indicated by a solid line. Changes in the fastening pressure (control pressure) when adjusted based only on the first function (differential pressure) during mode switching are indicated by broken lines, respectively.

  As is apparent from FIGS. 6 and 7, when the fastening pressure is adjusted based on the first function (differential pressure) during mode switching, the low speed and high speed clutches 7 and 8 are simultaneously operated. In the connected state, the differential pressure used in the first function does not correspond to the output torque of the engine 1 (is indefinite). In the case of this example, since the mode switching is performed in a state where the gear ratio of the toroidal type continuously variable transmission 4 is adjusted to the mode switching point (for example, the speed increasing ratio is 0.46), both the low speed and the high speed are switched. The differential pressure changes to 0 when the clutches 7 and 8 are simultaneously connected. As the differential pressure changes, the fastening pressure adjusted based on the first function (differential pressure) is also set to 0 regardless of the force (power, torque) output from the engine 1. Become. For this reason, when the fastening pressure is adjusted based on the first function (differential pressure) in this way, immediately after the completion of the mode switching {one clutch 6 (7) connected so far is disconnected. From immediately after} until the fastening pressure rises sufficiently (response delay), that is, as shown by hatching in FIGS. 6 and 7, the fastening pressure is insufficient. And when this shortage is remarkable, there exists a possibility of producing a slip in a clutch fastening part (power transmission part).

  On the other hand, in the case of this example, the clutch target value is obtained based on the second function, that is, “output torque (accelerator operation amount, engine rotation speed)” during mode switching as described above ( Therefore, even when the low-speed and high-speed clutches 7 and 8 are simultaneously connected, an appropriate engagement pressure corresponding to the engine torque output from the engine 1 at that time can be maintained. In addition, when the mode is switched, it is possible to prevent a decrease (insufficiency) in the fastening pressure associated with the reversal of the direction of the torque (passing torque) passing through the toroidal type continuously variable transmission 4 (when the differential pressure becomes zero). . For this reason, the unnecessary fluctuation | variation of this fastening pressure can also be reduced (a fastening pressure does not change a lot), and the torque shift accompanying the fluctuation | variation of this fastening pressure can also be aimed at.

In the case of this example, as shown in the flowchart of FIG. 4, during the mode switching, based on the second function, the second driving mode corresponding to the current driving mode and the next driving mode to be realized is selected. Clutch target values A _L and A _H are obtained. Then, a larger value is set as an actual clutch target value (actual target value), and the hydraulic pressure is adjusted to the clutch target value (actual target value). For this reason, even when the required clutch pressure is different before and after the mode switching, it is possible to reliably prevent the engagement pressures of the first and second clutches from being insufficient from the start of the mode switching to immediately after the completion of the mode switching.

  In the above description, the present invention is combined with a toroidal continuously variable transmission and a planetary gear type transmission, and the rotation state of the output shaft is corrected with the input shaft rotated in one direction. The case where the present invention is applied to a continuously variable transmission equipped with a mode (low speed mode) capable of realizing a so-called geared neutral state that can be switched between rotation and reverse rotation has been described. However, the present invention combines a toroidal type continuously variable transmission and a planetary gear type transmission, a mode in which power is transmitted only by the toroidal type continuously variable transmission (low speed mode), and a planetary gear type which is a differential unit. The present invention can also be applied to a continuously variable transmission having a mode (high speed mode) for realizing a so-called power split state in which main power is transmitted by a transmission and the gear ratio is adjusted by the toroidal type continuously variable transmission. . The structure of the toroidal continuously variable transmission may be either a half toroidal type or a full toroidal type.

  Further, in the case of a structure capable of adjusting the hydraulic pressure introduced into the clutch device as in the present invention described above, the following technique can be realized. That is, although not shown, a clutch device is provided on the downstream side of the output shaft of the continuously variable transmission or the power transmission direction with respect to the output shaft, and the hydraulic pressure introduced into the clutch device is, for example, on the wheel side To adjust according to the torque (spike torque) applied to the output shaft. In this case, for example, as the torque increases, the hydraulic pressure (engagement pressure) introduced into the clutch device is reduced (for example, slipping occurs at the clutch fastening portion by reducing the torque, or connection is established by setting the torque to 0). If it is cut off), vibration (noise) due to transmission of the torque to the continuously variable transmission can be reduced. At the same time, even when a large deceleration torque is applied from the wheel side during sudden braking, the degree to which this torque is transmitted to the continuously variable transmission can be reduced, and an excessive load is applied to the continuously variable transmission. It is possible to prevent deterioration of durability and damage when this load is significant.

The block diagram similar to FIG. 8 which shows an example of embodiment of this invention. The same hydraulic circuit diagram as FIG. The hydraulic circuit diagram similar to FIG. 2 which shows another example. The flowchart which shows the operation | movement used as the characteristic of this invention. The diagram which shows the relationship between the speed ratio as the whole continuously variable transmission, and the fastening pressure (required clutch pressure) of a clutch apparatus. The diagram which shows the change of the state quantity of each part at the time of mode switching from low speed mode to high speed mode. The diagram which shows the change of the state quantity of each part at the time of mode switching from high speed mode to low speed mode. The block diagram of the conventional continuously variable transmission. The hydraulic circuit diagram which shows the mechanism for adjusting the gear ratio of the toroidal type continuously variable transmission built in this continuously variable transmission, and the pressing force which a pressing device generate | occur | produces. The diagram which shows one example of the relationship between the opening degree of the electromagnetic on-off valve for line pressure control, and the pressure reduction amount of the valve opening pressure of a pushing pressure regulation valve. The diagram which shows one example of the correlation of the speed ratio as the whole continuously variable transmission, and the gear ratio of a toroidal type continuously variable transmission. The diagram which shows the relationship between the speed ratio as the whole continuously variable transmission, the fastening pressure (required clutch pressure) of a clutch apparatus, and the pressing force (loading pressure) of a pressing device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 2 Damper 3 Input shaft 4 Toroidal type continuously variable transmission 5 Planetary gear type transmission 6 Clutch device 7 Low speed clutch 8 High speed clutch 9 Output shaft 10 Input side disk 11 Output side disk 12 Power roller 13 Actuator 14 Press device DESCRIPTION OF SYMBOLS 15 Gear ratio control unit 16 Controller 17 Stepping motor 18 Line pressure control electromagnetic on-off valve 19 Solenoid valve 20 Shifting solenoid valve 21 Control valve device 22 Gear ratio control valve 23 Differential pressure cylinders 24a, 24b Correction control valve 25 High speed clutch Switching valve 26 Low-speed clutch switching valve 27, 27a, 27b Oil pump 28 Oil reservoir 29 Push pressure adjusting valve 30 Low pressure side adjusting valve 31 Manual hydraulic switching valve 32 First pilot portion 33 Second pilot portion 34 Third Pilot part 35 Piston 36a, 36b Oil Chamber 37 Differential pressure take-off valve 38, 38a Pressure reducing valve 39, 39a, 39b Hydraulic sensor 40 Input side rotational speed sensor 41 Output side rotational speed sensor 42 Oil temperature sensor 43 Pilot chamber 44a, 44b Oil path 45 Low speed clutch solenoid valve 46 High speed Solenoid valve for clutch 47 Forward / reverse switching valve 48 Accelerator sensor 49 Engine controller 50 Primary line 51 Hydraulic chamber 52a, 52b Hydraulic chamber 53 Pump for clutch

Claims (4)

Toroidal continuously variable transmission and clutch device,
Of these, the toroidal continuously variable transmission includes a first disk and a second disk disposed concentrically and relatively rotatably, and the inner surfaces of the first and second disks facing each other. A plurality of power rollers that are sandwiched and transmit power between the first and second disks, a plurality of support members that rotatably support the power rollers, and each of the support members, Displacement in the axial direction of the pivot provided at both ends, and an actuator that changes the gear ratio between the first disk and the second disk,
In the continuously variable transmission, the clutch device is a hydraulic type that is connected based on the introduction of hydraulic pressure.
Clutch oil pressure adjusting means for adjusting the oil pressure to be introduced into the clutch device according to the operation status at that time, the clutch oil pressure adjusting means is a clutch target value corresponding to the oil pressure to be introduced into the clutch device. Is obtained based on at least a force passing through the toroidal type continuously variable transmission, and at least a second function obtained based on a force output from a drive source connected to the toroidal type continuously variable transmission. The first clutch target value obtained based on the first function is compared with the second clutch target value obtained based on the second function, and a larger value is actually calculated. A continuously variable transmission that is set as a clutch target value and adjusts the hydraulic pressure to the clutch target value. The actuator is hydraulic,
The force passing through the toroidal type continuously variable transmission is obtained based on the difference in hydraulic pressure between a pair of hydraulic chambers provided in the actuator,
The force output from the drive source is obtained based on the operation amount of the accelerator device for adjusting the output of the drive source.
The continuously variable transmission according to claim 1. Composed of a toroidal continuously variable transmission and a differential unit through a clutch device,
Of these, the clutch device includes a first clutch that is connected when realizing the first mode for increasing the reduction ratio and is disconnected when realizing the second mode for reducing the same. And a second clutch that is connected when realizing the first mode and disconnected when realizing the first mode.
Obtained based on the first clutch target value corresponding to the current travel mode, which is obtained based on the first function during operation in the first mode or the second mode, and the second function. Is compared with the second clutch target value corresponding to the current travel mode, a larger value is set as the actual clutch target value, and the hydraulic pressure is adjusted to this clutch target value.
The continuously variable transmission according to any one of claims 1 and 2. When switching the mode between the first mode and the second mode, the clutch device connects a clutch that has not been connected by one of the first clutch and the second clutch. From the same time, by disconnecting the clutch that was previously connected with the other clutch, the time for both these clutches to be connected at the same time was set.
At the time of mode switching between the first mode and the second mode, based on the second function, a target value corresponding to the current travel mode and a target value corresponding to the travel mode to be realized next , Respectively, and a larger value between these target values is set as an actual clutch target value, and the hydraulic pressure is adjusted to this clutch target value.
The continuously variable transmission according to claim 3.

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