JP2012241799A - Hydraulic control device of belt type continuously variable transmission for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydraulic control device of a belt type continuously variable transmission for a vehicle, with improved drivability in controlling speed changing pressure.SOLUTION: In speed changing pressure control, the hydraulic control device of a belt type continuously variable transmission for a vehicle feedback controls a difference between a target gear ratio γ* and an actual gear ratio γ, while feed-forward controlling the hydraulic pressure that determines thrust for variable pulleys 42, 46, on the basis of the speed changing differential thrust characteristics determined in advance. On the basis of the control amount Winfb in the feedback control with respect to the past speed changing pressure control performed, speed changing differential thrust characteristics relating to the feed-forward control is learning controlled. Feed-forward control is performed in accordance with the speed changing differential thrust characteristics for each unit by altering the speed changing differential thrust characteristics, using the feedback control amount Winfb at the speed changing as a learned value. The increase in changes in speed in the speed changing is prevented to properly reduce discomfort of the driver.

Description

  The present invention relates to a hydraulic control device for a belt-type continuously variable transmission for a vehicle, and more particularly, to an improvement for improving drivability during speed change pressure control.

  2. Description of the Related Art A vehicular continuously variable transmission that is connected to an engine and can change the output of the engine continuously is known. For example, a belt type continuously variable transmission or the like that changes the gear ratio by changing the engagement diameter of the belt while transmitting pressure by clamping the belt with hydraulic pressure. In addition, in such a belt type continuously variable transmission, a technique for improving the shift response has been proposed. For example, the control device for a continuously variable transmission described in Patent Document 1 is this. According to this technique, the deviation between the estimated change amount of the hydraulic oil capacity in the primary oil chamber from the start of the shift to the end of the shift and the actually detected change is calculated, and the shift is performed based on the deviation. By performing learning control on the hydraulic flow rate according to the above, it is possible to correct a gear ratio error due to manufacturing variation of the flow rate control means and improve the follow-up performance of the gear ratio with respect to a desired gear ratio.

JP 2003-227564 A Japanese Patent Laid-Open No. 7-4508 Japanese Patent Laid-Open No. 9-210189 JP 2008-57588 A JP 2003-343709 A JP 2005-20769 A

  In the transmission pressure control of the belt type continuously variable transmission according to the prior art as described above, feedback control is performed based on the deviation between the target transmission ratio and the actual transmission ratio, and a predetermined transmission difference thrust is determined. It is conceivable to feed-forward control the hydraulic pressure that determines the thrust in the variable pulley based on the characteristics. However, the shift difference thrust characteristics used in such feedforward control vary greatly from unit to unit, for example, due to variations in the manufacturing stage. If the shift difference thrust characteristics differ from the planned shift difference thrust characteristics in feedforward control, correction by feedback control is performed. There is a concern that the driver may feel uncomfortable due to an increase in the shift speed change. Such a problem is not yet known and has been newly found by the present inventors in the course of research. For this reason, there has been a demand for the development of a hydraulic control device for a belt-type continuously variable transmission for a vehicle that improves drivability at the time of shifting pressure control.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a hydraulic control device for a belt-type continuously variable transmission for a vehicle that improves drivability at the time of shifting pressure control. It is in.

  In order to achieve such an object, the gist of the first aspect of the present invention is that an input side variable pulley and an output side variable pulley whose effective diameter is variable are wound between the pair of variable pulleys. A vehicle that performs transmission pressure control for changing a transmission ratio of a belt-type continuously variable transmission by controlling a hydraulic pressure that determines a thrust in each of the pair of variable pulleys with respect to the belt-type continuously variable transmission having a transmission belt. A hydraulic control device for a belt type continuously variable transmission, wherein in the speed change pressure control, the difference between a target speed ratio and an actual speed ratio is feedback controlled, and the variable based on a predetermined speed difference thrust characteristic Feedforward control of the hydraulic pressure that determines the thrust in the pulley, based on the control amount in the feedback control in the shift pressure control performed in the past It is characterized in performing the learning control of the shifting thrust difference characteristic according to the feedforward control.

  In this way, in the speed change pressure control, the difference between the target speed ratio and the actual speed ratio is feedback controlled, and the hydraulic pressure that determines the thrust in the variable pulley based on a predetermined speed difference thrust characteristic is fed forward. Feedback control at the time of gear shifting, since learning control of gear shift difference thrust characteristics related to the feedforward control is performed based on a control amount in the feedback control in gear shifting pressure control performed in the past. By changing the shift difference thrust characteristics using the control amount as a learning value, it is possible to perform feed-forward control according to the shift difference thrust characteristics for each unit, suppressing an increase in shift speed changes and feeling uncomfortable to the driver. Can be suitably suppressed. That is, it is possible to provide a hydraulic control device for a belt-type continuously variable transmission for a vehicle that improves drivability during speed change pressure control.

  Here, the subject matter of the second invention, which is subordinate to the first invention, is that, with regard to learning control of the shift difference thrust characteristic related to the feedforward control, the hydraulic pressure is increased with respect to the initial setting characteristic. This learning control is executed, but the learning control to the side for reducing the hydraulic pressure is prohibited. In this way, the shift difference thrust characteristic can be changed with the feedback control amount at the time of shifting as the learning value while suppressing slippage of the transmission belt due to erroneous learning.

  The gist of the third invention subordinate to the first to second inventions is that a shift speed of the shift pressure control is determined in advance with respect to the learning control of the shift difference thrust characteristic relating to the feedforward control. The learning control is executed when it is less than the threshold value. In this way, it is possible to perform feed-forward control according to the shift difference thrust characteristics for each unit, particularly during slow shifts, where the influence of variations among units is large, and driving while suppressing an increase in shift speed change. Discomfort to the person can be suitably suppressed.

  Further, the gist of the fourth invention subordinate to any of the first invention, the second invention, the third invention subordinate to the first invention, and the third invention subordinate to the second invention is the feed. Regarding the learning control of the shift difference thrust characteristic related to the forward control, when the control amount in the feedback control in the previous shift pressure control is equal to or greater than a predetermined threshold, the shift related to the feedforward control based on the control amount The learning control of the differential thrust characteristic is executed. In this way, learning control of the shift difference thrust characteristic using the feedback control amount at the time of shifting as a learning value can be performed in an efficient and practical manner.

It is a figure explaining the schematic structure of the power transmission path | route which comprises the vehicle to which this invention is applied suitably. It is a block diagram explaining the principal part of the control system provided in the vehicle. It is a hydraulic circuit diagram which shows the principal part regarding the hydraulic control regarding the shift of a belt-type continuously variable transmission among hydraulic control circuits. It is a functional block diagram explaining the principal part of the control function of an electronic controller. It is a figure which shows an example for demonstrating a thrust required for transmission control. It is a block diagram which shows the control structure of a present Example. It is a figure which shows an example of the speed change map used when calculating | requiring the target input shaft rotational speed in the hydraulic control regarding the speed change of a continuously variable transmission. It is a figure which shows an example of the map previously calculated | required experimentally and memorize | stored in advance of engine rotation speed and engine torque by making intake air quantity into a parameter. It is a figure which shows an example of the map previously calculated | required experimentally as a predetermined operating characteristic of a torque converter, and was memorize | stored. It is a figure which shows an example of the thrust ratio map calculated | required experimentally beforehand and memorize | stored with the target speed ratio as a parameter and the reciprocal number of a safety factor, and a thrust ratio. It is a figure which shows an example of the difference thrust map calculated | required experimentally beforehand and memorize | stored in the target shift speed and the shift difference thrust. It is a figure explaining the learning control of the characteristic map of a present Example. It is a time chart which illustrates various waveforms at the time of shift pressure control of a belt type continuously variable transmission. It is a figure explaining the learning control of the characteristic map by a present Example, and has illustrated the relationship by the side of the upshift in a primary pulley. It is a figure explaining the learning control of the characteristic map by a present Example, and has illustrated the relationship by the side of the downshift in a primary pulley. It is a flowchart explaining the principal part of the transmission pressure control of the belt-type continuously variable transmission by the electronic controller of a present Example. It is a flowchart explaining the principal part of another example of the transmission pressure control of the belt-type continuously variable transmission by the electronic control apparatus of a present Example.

  In the present invention, preferably, the input-side thrust and the output-side thrust are each controlled by configuring a hydraulic control circuit so as to independently control pulley pressure applied to the input-side variable pulley and the output-side variable pulley. It can be controlled directly or indirectly.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram illustrating a schematic configuration of a power transmission path from an engine 12 to a drive wheel 24 constituting a vehicle 10 to which the present invention is preferably applied. In FIG. 1, for example, power generated by an engine 12 used as a driving force source for traveling is converted into a torque converter 14 as a fluid transmission device, a forward / reverse switching device 16, a belt type continuously variable transmission (hereinafter referred to as a belt type continuously variable transmission). , Continuously variable transmission (CVT) 18, reduction gear device 20, differential gear device 22, etc., are sequentially transmitted to the left and right drive wheels 24.

  The torque converter 14 is connected to the forward / reverse switching device 16 via a pump impeller 14p connected to the crankshaft 13 of the engine 12 and a turbine shaft 30 corresponding to an output side member of the torque converter 14. A turbine impeller 14t is provided to transmit power through a fluid. Further, a lockup clutch 26 is provided between the pump impeller 14p and the turbine impeller 14t. When the lockup clutch 26 is completely engaged, the pump impeller 14p and the turbine impeller 14t are It can be rotated together. The pump impeller 14p controls the speed of the continuously variable transmission 18, generates a belt clamping pressure in the continuously variable transmission 18, controls the torque capacity of the lockup clutch 26, Mechanical oil generated when the engine 12 is rotationally driven by hydraulic pressure for switching the power transmission path in the advance switching device 16 and supplying lubricating oil to each part of the power transmission path of the vehicle 10. A pump 28 is connected.

  The forward / reverse switching device 16 is composed mainly of a forward clutch C1, a reverse brake B1, and a double pinion type planetary gear device 16p, and the turbine shaft 30 of the torque converter 14 is integrated with a sun gear 16s. The input shaft 32 of the continuously variable transmission 18 is integrally connected to the carrier 16c, while the carrier 16c and the sun gear 16s are selectively connected via the forward clutch C1. The ring gear 16r is selectively fixed to a housing 34 as a non-rotating member via a reverse brake B1. Each of the forward clutch C1 and the reverse brake B1 is preferably a hydraulic friction engagement device that is frictionally engaged by a hydraulic cylinder.

  In the forward / reverse switching device 16 configured as described above, when the forward clutch C1 is engaged and the reverse brake B1 is released, the forward / reverse switching device 16 is brought into an integral rotation state. As a result, the turbine shaft 30 is directly connected to the input shaft 32, and the forward power transmission path is established (achieved), so that the driving force in the forward direction is transmitted to the continuously variable transmission 18 side. When the reverse brake B1 is engaged and the forward clutch C1 is released, the forward / reverse switching device 16 establishes (achieves) a reverse power transmission path, and the input shaft 32 The turbine shaft 30 is rotated in the reverse direction, and the driving force in the reverse direction is transmitted to the continuously variable transmission 18 side. When both the forward clutch C1 and the reverse brake B1 are released, the forward / reverse switching device 16 is in a neutral state (power transmission cut-off state) in which power transmission is cut off.

The engine 12 is an internal combustion engine such as a gasoline engine or a diesel engine, and functions as a driving force source (main power source) in the vehicle 10. In addition, the intake pipe 36 of the engine 12 is provided with an electronic throttle valve 40 for electrically controlling the intake air amount Q _AIR of the engine 12 using a throttle actuator 38 as shown in FIG. Yes.

  The continuously variable transmission 18 includes an input side member provided on the input shaft 32 and a primary pulley (primary sheave) 42 that is an input side variable pulley having a variable effective diameter, and an output side provided on the output shaft 44. A secondary pulley (secondary sheave) 46 (hereinafter simply referred to as variable pulleys 42 and 46 unless otherwise specified), and a pair of variable pulleys 42 and 46, which are output-side variable pulleys having variable effective diameters as members. And a transmission belt 48 wound around the belt. With such a configuration, in the continuously variable transmission 18, power is transmitted through a frictional force between the pair of variable pulleys 42 and 46 and the transmission belt 48. For example, the transmission belt 48 has an endless annular shape as a whole, and is overlapped in the thickness direction in a state of being in close contact with each other along a pair of endless annular tape-like hoops (belts). It has a large number of elements (frames). This element is formed with a pair of hoop engaging grooves formed so as to open to the side, and the pair of hoops are engaged with the hoop engaging grooves.

  The primary pulley 42 is a fixed rotating body (fixed sheave) 42a as an input-side fixed rotating body fixed to the input shaft 32, and is not rotatable relative to the input shaft 32 and is movable in the axial direction. A movable rotating body (movable sheave) 42b as an input side movable rotating body provided on the input side, and an input side thrust (primary thrust) Win (= primary pressure) in the primary pulley 42 for changing the V groove width between them. A primary side hydraulic cylinder (input side hydraulic cylinder) 42c as a hydraulic actuator that provides (Pin × pressure receiving area) is provided. The secondary pulley 46 includes a fixed rotating body (fixed sheave) 46 a as an output side fixed rotating body fixed to the output shaft 44, and a relative rotation around the axis with respect to the output shaft 44 and in the axial direction. A movable rotator (movable sheave) 46b as an output side movable rotator provided so as to be movable, and an output side thrust (secondary thrust) Wout (=) in the secondary pulley 46 for changing the V groove width between them. A secondary hydraulic cylinder (output hydraulic cylinder) 46c as a hydraulic actuator that applies secondary pressure Pout × pressure receiving area) is provided.

As shown in FIG. 3 to be described later, the primary pressure Pin that is the hydraulic pressure to the oil chamber 42d of the primary hydraulic cylinder 42c and the secondary pressure Pout that is the hydraulic pressure to the oil chamber 46d of the secondary hydraulic cylinder 46c are the vehicle The pressure control is independently controlled by the hydraulic control circuit 100 provided in the system 10. Thereby, the primary thrust Win that is the thrust in the primary pulley 42 and the secondary thrust Wout that is the thrust in the secondary pulley 46 are controlled directly or indirectly, respectively, so that each of the pair of variable pulleys 42 and 46 is controlled. As the V groove width of the transmission belt 48 is changed, the engagement diameter (effective diameter) of the transmission belt 48 is changed, and the transmission gear ratio (gear ratio) γ of the continuously variable transmission 18 (= input shaft rotational speed N _IN / output shaft rotational speed). N _OUT ) is continuously changed, and the frictional force (belt clamping pressure) between the pair of variable pulleys 42 and 46 and the transmission belt 48 is controlled so that the transmission belt 48 does not slip. The

In the continuously variable transmission 18, the primary thrust Win and the secondary thrust Wout are controlled as described above, so that the actual transmission ratio (actual transmission ratio) γ is targeted while preventing the transmission belt 48 from slipping. The transmission ratio is γ ^* . The input shaft rotational speed N _IN is the rotational speed of the input shaft 32, and the output shaft rotational speed N _OUT is the rotational speed of the output shaft 44. As is clear from FIG. 1, in this embodiment, the input shaft rotational speed N _IN is the same as the rotational speed of the primary pulley 42, and the output shaft rotational speed N _OUT is the same as the rotational speed of the secondary pulley 46. Are the same.

In the continuously variable transmission 18, for example, when the primary pressure Pin is increased, the V groove width of the primary pulley 42 is narrowed to reduce the speed ratio γ. That is, the continuously variable transmission 18 is upshifted by increasing the primary pressure Pin. When the primary pressure Pin is lowered, the V groove width of the primary pulley 42 is widened and the speed ratio γ is increased. That is, the continuously variable transmission 18 is downshifted by decreasing the primary pressure Pin. Therefore, when the V groove width of the primary pulley 42 is minimized, the minimum speed ratio γmin (highest speed side speed ratio, maximum Hi) is achieved as the speed ratio γ of the continuously variable transmission 18. When the V groove width of the primary pulley 42 is maximized, the maximum speed ratio γmax (the lowest speed side speed ratio, the lowest) is achieved as the speed ratio γ of the continuously variable transmission 18. In the continuously variable transmission 18, slippage (belt slip) of the transmission belt 48 is prevented by the primary pressure Pin (primary thrust Win is also agreed) and the secondary pressure Pout (secondary thrust Wout is also agreed). The target gear ratio γ ^* is realized by the mutual relationship between the primary thrust Win and the secondary thrust Wout, and the target shift is not realized only by one pulley pressure (thrust is also agreed).

  FIG. 2 is a block diagram illustrating a main part of a control system provided in the vehicle 10 for controlling the engine 12, the continuously variable transmission 18, and the like. The vehicle 10 according to the present embodiment is provided with an electronic control device 50 including a control device (hydraulic control device) for a vehicle belt type continuously variable transmission related to, for example, shift control of the continuously variable transmission 18. . The electronic control device 50 is configured to include a so-called microcomputer having, for example, a CPU, a RAM, a ROM, and an input / output interface, and the CPU is stored in advance in the ROM using a temporary storage function of the RAM. Various controls relating to the vehicle 10 are executed by performing signal processing according to a program. For example, the electronic control unit 50 performs output control of the engine 12, shift control of the continuously variable transmission 18, belt clamping pressure control, torque capacity control of the lockup clutch 26, and the like. If necessary, it is divided into an engine control unit, a transmission control unit for the continuously variable transmission 18, and a hydraulic control unit for the lockup clutch 26.

The electronic control device 50 is supplied with signals from various sensors and switches provided in the vehicle 10. For example, detected by the rotation angle (position) A _CR and the rotational speed signal representing the (engine rotational speed) N _E of the engine 12, a turbine rotational speed sensor 54 of the crankshaft 13 detected by the engine rotational speed sensor 52 A signal representing a rotational speed (turbine rotational speed) _NT of the turbine shaft 30; a signal representing an input shaft rotational speed N _IN which is an input rotational speed of the continuously variable transmission 18 detected by the input shaft rotational speed sensor 56; A signal representing the output shaft rotational speed N _OUT which is the output rotational speed of the continuously variable transmission 18 corresponding to the vehicle speed V detected by the output shaft rotational speed sensor 58, the electronic throttle valve 40 detected by the throttle sensor 60. signal representing the throttle valve opening theta _TH, a signal representing the cooling water temperature TH _W of the engine 12 detected by a coolant temperature sensor 62, intake Signal representing the intake air quantity Q _AIR of the engine 12 detected by the air flow sensor 64, the accelerator opening is an operation amount of the accelerator pedal as an acceleration demand of the detected driver by the accelerator opening sensor 66 A _CC , A signal indicating a brake-on B _ON indicating a state in which a foot brake as a service brake detected by the foot brake switch 68 is operated, a continuously variable transmission 18 detected by the CVT oil temperature sensor 70, etc. signal representative of the oil temperature TH _oIL of the working oil, lever lever position (operation position) of the shift lever detected by the position sensor 72 signals representative of P _SH, the battery temperature detected by the battery sensor 76 TH _BAT and the battery output current (Battery charge / discharge current) Signal indicating I _BAT or battery voltage V _BAT , secondary pressure sensor 78 A signal indicating the secondary pressure Pout, which is the hydraulic pressure supplied to the secondary pulley 46, is detected. The electronic control unit 50 sequentially calculates the state of charge (charge capacity) SOC of the battery (power storage device) based on, for example, the battery temperature TH _BAT , the battery charge / discharge current I _BAT , and the battery voltage V _BAT . Further, for example, the actual speed ratio γ (= N _IN / N _OUT ) of the continuously variable transmission 18 is sequentially calculated based on the output shaft rotational speed N _OUT and the input shaft rotational speed N _IN .

Further, the electronic control device 50 is configured to output signals for controlling the operation of each part in the vehicle 10. For example, an engine output control command signal S _E for output control of the engine 12, a hydraulic control command signal S _CVT for hydraulic control related to the shift of the continuously variable transmission 18, and the like are output. Specifically, as the engine output control command signal S _E , the throttle signal for controlling the opening / closing of the electronic throttle valve 40 by driving the throttle actuator 38, and the amount of fuel injected from the fuel injection device 80 are set. An injection signal for controlling, an ignition timing signal for controlling the ignition timing of the engine 12 by the ignition device 82, and the like are output. The hydraulic control command signal S _{CVT includes} a command signal for driving the linear solenoid valve SLP that regulates the primary pressure Pin, a command signal for driving the linear solenoid valve SLS that regulates the secondary pressure Pout, and the line hydraulic pressure P A command signal or the like for driving the linear solenoid valve SLT for controlling _L is output to the hydraulic control circuit 100 described later with reference to FIG.

  FIG. 3 is a hydraulic circuit diagram showing a main part related to hydraulic control (shift pressure control) related to shifting of the continuously variable transmission 18 in the hydraulic control circuit 100 provided in the vehicle 10. As shown in FIG. 3, the hydraulic control circuit 100 includes, for example, the mechanical oil pump 28, a primary pressure control valve 110 that regulates the primary pressure Pin, a secondary pressure control valve 112 that regulates the secondary pressure Pout, A primary regulator valve (line hydraulic pressure regulating valve) 114, a modulator valve 116, a linear solenoid valve SLT, a linear solenoid valve SLP, a linear solenoid valve SLS, and the like are provided.

The line oil pressure P _L is based on, for example, the control oil pressure P _SLT that is the output oil pressure of the linear solenoid valve SLT by the relief type primary regulator valve 114 using the operating oil pressure output (generated) from the oil pump 28 as a source pressure. The pressure is adjusted to a value according to the engine load and the like. Specifically, the line oil pressure P _L is based on a control oil pressure P _SLT that is set to obtain a hydraulic pressure obtained by adding a predetermined margin (margin) to the higher hydraulic pressure of the primary pressure Pin and the secondary pressure Pout. It is regulated. Therefore, it is avoided that the line oil pressure P _L which is the original pressure is insufficient in the pressure adjusting operation of the primary pressure control valve 110 and the secondary pressure control valve 112, and the line oil pressure P _L is not increased unnecessarily. Is possible. Moreover, modulator pressure P _M, the electronic control unit control pressure P _SLT that is controlled by 50, the linear solenoid valve SLP output hydraulic and is controlled oil pressure P _SLP, and the control oil pressure which is the output oil pressure of the linear solenoid valve SLS Each of the source pressures of P _SLS is adjusted to a constant pressure by the modulator valve 116 using the line oil pressure P _L as the source pressure.

The primary pressure control valve 110 is provided so as to be movable in the axial direction so as to open and close the input port 110i and supply the line oil pressure P _L from the input port 110i to the primary pulley 42 via the output port 110t. 110a, a spring 110b as an urging means for urging the spool valve element 110a in the valve opening direction, and a control hydraulic pressure for accommodating the spring 110b and applying thrust in the valve opening direction to the spool valve element 110a An oil chamber 110c that receives P _SLP , a feedback oil chamber 110d that receives the line oil pressure P _L output from the output port 110t to give a thrust in the valve closing direction to the spool valve element 110a, and a spool valve element 110a receiving the modulator pressure P _M in order to impart a closing direction of thrust An oil chamber 110e is provided.

Primary pressure control valve 110 configured as described above, for example, supplied to the control oil pressure P primary hydraulic cylinder 42c of the _SLP line pressure P _L temper pressure control to the pilot pressure the primary pulley 42 (42d oil chamber) To do. As a result, the primary pressure Pin supplied to the primary hydraulic cylinder 42c is controlled. For example, when the control hydraulic pressure P _SLP output from the linear solenoid valve _SLP is increased from a state where a predetermined hydraulic pressure is supplied to the primary hydraulic cylinder 42c, the spool valve element 110a of the primary pressure control valve 110 is Move to the upper side of FIG. Thereby, the primary pressure Pin to the primary hydraulic cylinder 42c is increased. On the other hand, when the control hydraulic pressure P _SLP output from the linear solenoid valve _SLP is lowered from the state where a predetermined hydraulic pressure is supplied to the primary hydraulic cylinder 42c, the spool valve element 110a of the primary pressure control valve 110 is reduced. Moves downward in FIG. As a result, the primary pressure Pin to the primary hydraulic cylinder 42c is reduced.

  An oil supply / discharge conduit for the primary pulley 42, that is, an oil passage 118 between the primary-side hydraulic cylinder 42c (oil chamber 42d) and the primary pressure control valve 110 is provided with an orifice 120 for the purpose of failsafe or the like. Is provided. By providing the orifice 120, for example, even if the linear solenoid valve SLP fails, the internal pressure of the primary hydraulic cylinder 42c is not suddenly reduced. Thereby, for example, sudden deceleration of the vehicle 10 due to a failure of the linear solenoid valve SLP is suppressed.

The secondary pressure control valve 112 is provided so as to be movable in the axial direction, thereby opening and closing the input port 112i and supplying the line oil pressure P _L from the input port 112i to the secondary pulley 46 via the output port 112t as the secondary pressure Pout. A spool valve element 112a, a spring 112b as an urging means for urging the spool valve element 112a in the valve opening direction, and the spring valve 112b is accommodated and imparts thrust in the valve opening direction to the spool valve element 112a. An oil chamber 112c that receives the control hydraulic pressure P _SLS to perform the above operation, a feedback oil chamber 112d that receives the secondary pressure Pout output from the output port 112t in order to give a thrust in the valve closing direction to the spool valve element 112a, Applies thrust in the valve closing direction to the spool valve element 112a An oil chamber 112e that accepts modulator pressure P _M in order, comprises.

Secondary pressure control valve 112 configured as described above, for example, supplied to the control oil pressure P _SLS secondary side hydraulic cylinder 46c of the secondary pulley 46 by the line pressure P _L as a pilot pressure regulating control to control (oil chamber 46d) To do. Thereby, the secondary pressure Pout supplied to the secondary hydraulic cylinder 46c is controlled. For example, when the control hydraulic pressure P _SLS output from the linear solenoid valve _SLS is increased from a state in which a predetermined hydraulic pressure is supplied to the secondary hydraulic cylinder 46c, the spool valve element 112a of the secondary pressure control valve 112 is Move to the upper side of FIG. As a result, the secondary pressure Pout to the secondary hydraulic cylinder 46c is increased. On the other hand, when the control hydraulic pressure P _SLS output from the linear solenoid valve _SLS is lowered from the state where a predetermined hydraulic pressure is supplied to the secondary hydraulic cylinder 46c, the spool valve element 112a of the secondary pressure control valve 112 is reduced. Moves downward in FIG. As a result, the secondary pressure Pout to the secondary hydraulic cylinder 46c is reduced.

  An oil supply / discharge conduit for the secondary pulley 46, that is, an oil passage 122 between the secondary hydraulic cylinder 46 c (oil chamber 46 d) and the secondary pressure control valve 112 is provided with an orifice 124 for the purpose of fail-safe or the like. Is provided. By providing the orifice 124, for example, even if the linear solenoid valve SLS breaks down, the internal pressure of the secondary hydraulic cylinder 46c is not suddenly reduced. Thereby, for example, belt slippage due to a failure of the linear solenoid valve SLS is prevented.

  In the hydraulic control circuit 100 configured as described above, for example, the primary pressure Pin regulated by the linear solenoid valve SLP and the secondary pressure Pout regulated by the linear solenoid valve SLS are transmitted through the transmission belt 48 and the variable pulley 42. , 46 is controlled so as to generate a belt clamping pressure which does not cause slippage between the pair of variable pulleys 42, 46 and does not increase unnecessarily. Further, as will be described later, the continuously variable transmission is obtained by changing the thrust ratio τ (= Wout / Win) of the pair of variable pulleys 42 and 46 by the mutual relationship between the primary pressure Pin and the secondary pressure Pout. The gear ratio γ of 18 is changed. For example, the gear ratio γ is increased as the thrust ratio τ is increased (that is, the continuously variable transmission 18 is downshifted).

FIG. 4 is a functional block diagram for explaining the main part of the control function provided in the electronic control unit 50. The engine output control means 130 shown in FIG. 4 controls the output of the engine 12. For example, an engine output control command signal S _E such as a throttle signal, an injection signal, and an ignition timing signal is output to the throttle actuator 38, the fuel injection device 80, the ignition device 82, and the like for output control of the engine 12. Specifically, a target engine torque T _E ^* for obtaining a driving force (driving torque) corresponding to the accelerator opening A _CC is set, and the throttle actuator 38 is set so as to obtain the target engine torque T _E ^*. In addition to controlling the opening and closing of the electronic throttle valve 40, the fuel injection amount is controlled by the fuel injection device 80, and the ignition timing is controlled by the ignition device 82.

The transmission hydraulic pressure control means 132 performs transmission pressure control for controlling the transmission ratio γ in the continuously variable transmission 18. For example, the command value (or target primary pressure Pin ^* ) of the primary pressure Pin is set so as to achieve the target speed ratio γ ^* of the continuously variable transmission 18 while preventing belt slippage of the continuously variable transmission 18. The primary command pressure Pintgt and the secondary command pressure Pouttgt as the command value (or target secondary pressure Pout ^* ) of the secondary pressure Pout are determined, and the primary command pressure Pintgt and the secondary command pressure Pouttgt are output to the hydraulic control circuit 100. To do. That is, in the present embodiment, the electronic control device 50 corresponds to a hydraulic control device for a belt type continuously variable transmission.

Here, the hydraulic control circuit 100 according to the present embodiment operates on the secondary pulley 46 (secondary hydraulic cylinder 46c) only on the secondary pulley 46 side which is one side of the pair of variable pulleys 42 and 46. A secondary pressure sensor 78 is provided as a hydraulic pressure sensor for detecting the secondary pressure Pout. In other words, a hydraulic sensor for detecting the actual primary pressure Pin acting on the primary pulley 42 (primary hydraulic cylinder 42c) is not provided. For this reason, for example, the transmission hydraulic pressure control means 132 executes feedback control in which the detected value of the secondary pressure sensor 78 (a signal indicating the actual secondary pressure Pout) is set to the target secondary pressure Pout ^* corresponding to the target secondary thrust Wout ^*. can do. As a result, the thrust (pulley pressure) can be controlled more accurately on the secondary pulley 46 side than on the primary pulley 42 side where no hydraulic pressure sensor is provided. That is, in the hydraulic control circuit 100 of this embodiment, the secondary pulley 46, which is one of the primary pulley 42 and the secondary pulley 46, is compared with the primary pulley 42, which is the other, and thrust (pulley pressure) is controlled with high accuracy. can do.

In the hydraulic control circuit 100 configured as described above, a belt slip limit thrust (hereinafter referred to as a thrust necessary for preventing belt slip with the minimum necessary thrust (necessary thrust), that is, thrust immediately before belt slip occurs). , Slip limit thrust) is set as the target thrust, the hydraulic control accuracy is relatively inferior (that is, feedback control cannot be performed based on the deviation between the detected value of the hydraulic sensor and the target value). In order to ensure this, it is necessary to add a thrust component corresponding to hydraulic pressure variation, which is a difference between the hydraulic pressure command value (primary command pressure Pintgt) and the actual hydraulic pressure (actual primary pressure Pin), to the slip limit thrust. Then, from the mutual relationship between the primary pressure Pin (primary thrust Win) and the secondary pressure Pout (secondary thrust Wout) based on the thrust ratio τ (= Wout / Win) for realizing the target shift, the primary pulley 42 side hydraulic pressure is determined. The target secondary thrust Wout ^* must also be increased corresponding to the thrust corresponding to the variation, and the fuel consumption may be deteriorated. Even if the hydraulic sensor is not provided, the thrust can be corrected by feedback control based on the speed ratio deviation Δγ (= γ ^* −γ) between the target speed ratio γ ^* and the actual speed ratio γ. Regarding the realization of the shift, the hydraulic control accuracy is not necessarily good.

Therefore, in this embodiment, for example, on the secondary pulley 46 side with relatively good hydraulic control accuracy, the slip limit thrust on the secondary pulley 46 side is ensured, and the slip limit thrust on the primary pulley 42 side is also secured. That is, the belt torque capacity guarantee of both the pair of variable pulleys 42 and 46 is realized. Further, on the primary pulley 42 side where the hydraulic control accuracy is relatively inferior, a target primary thrust Win ^* corresponding to the target secondary thrust Wout ^* for guaranteeing the prevention of the belt slip is set, thereby realizing a target shift. At this time, feedback control based on the gear ratio deviation Δγ is executed in order to avoid fuel consumption deterioration due to the oil pressure variation on the primary pulley 42 side.

Specifically, the transmission hydraulic pressure control means 132 is, for example, a secondary pulley side slip limit thrust Woutlmt that is a slip limit thrust on the secondary pulley 46 side, and a primary pulley side slip limit that is a slip limit thrust on the primary pulley 42 side. The thrust on the secondary pulley 46 side required for shift control calculated based on the thrust Winlmt (in this embodiment, the primary pulley side slip limit thrust Winlmt (g) subjected to the lower limit guard process as described later is used). The larger one of the secondary pulley side shift control thrust Woutsh is selected as the target secondary thrust Wout ^* . Further, the transmission hydraulic pressure control means 132, for example, a primary pulley side transmission control thrust Winsh which is a thrust on the primary pulley 42 side necessary for the transmission control calculated based on the selected target secondary thrust Wout ^* , Set as target primary thrust Win ^* . Further, the transmission hydraulic pressure control means 132 performs the target primary thrust Win ^* (that is, primary pulley side transmission control) by feedback control of the primary thrust Win based on the transmission ratio deviation Δγ between the target transmission ratio γ ^* and the actual transmission ratio γ, for example. The thrust (Winsh) is corrected.

The gear ratio deviation Δγ may be a deviation between the target value and the actual value in the parameter corresponding to the gear ratio γ on a one-to-one basis. For example, instead of the gear ratio deviation Δγ, the deviation ΔXin (= Xin ^* −) between the target pulley position (target sheave position) Xin ^* on the primary pulley 42 side and the actual pulley position (actual sheave position) Xin (see FIG. 3). Xin), deviation ΔXout (= Xout ^* −Xout) between the target sheave position Xout ^* on the secondary pulley 46 side and the actual sheave position Xout (see FIG. 3), the target belt engagement diameter Rin ^* on the primary pulley 42 side and the actual Deviation ΔRin (= Rin ^* −Rin) from the belt engagement diameter Rin (see FIG. 3), deviation ΔRout (= from the target belt engagement diameter Rout ^* on the secondary pulley 46 side and the actual belt engagement diameter Rout (see FIG. 3) Rout ^* −Rout), a deviation ΔN _IN (= N _IN ^* −N _IN ) between the target input shaft rotational speed N _IN ^* and the actual input shaft rotational speed N _IN can be used.

The thrust necessary for the shift control is, for example, a thrust necessary for realizing the target shift, and a thrust necessary for realizing the target speed ratio γ ^* and the target speed. This speed change is, for example, the change amount dγ (= dγ / dt) of the speed ratio γ per unit time. In this embodiment, the sheave position movement amount (element (block) per element (block) of the transmission belt 48 ( dX / dNelm) (dX: sheave position change amount that is the axial displacement of the movable sheave per unit time, ie sheave position change speed (= dX / dt) [mm / ms], dNelm: per unit time Number of elements (blocks) to be engaged with the pulley [pieces / ms]). Accordingly, the target shift speed is represented by the primary target shift speed (dXin / dNelmin) and the secondary target shift speed (dXout / dNelmout).

Specifically, the primary thrust Win and the secondary thrust Wout in a steady state (a state in which the speed ratio γ is constant) are referred to as balance thrust (steady thrust) Wbl (for example, primary balance thrust Winbl and secondary balance thrust Woutbl). Is the thrust ratio τ (= Woutbl / Winbl) of the pair of variable pulleys 42 and 46. Further, when the primary thrust Win and the secondary thrust Wout are in a steady state in which a constant gear ratio γ is maintained, if a certain thrust is added to or subtracted from the thrust of one of the pair of variable pulleys 42 and 46, the steady state is obtained. The gear ratio γ is changed to change, and a speed change speed (dX / dNelm) corresponding to the magnitude of the thrust added or subtracted is generated. This added or subtracted thrust is referred to as shift difference thrust (transient thrust) ΔW (for example, primary shift difference thrust ΔWin and secondary shift difference thrust ΔWout). Therefore, when one thrust is set, the thrust required for the speed change control is the target speed ratio γ ^* corresponding to one thrust based on the thrust ratio τ for maintaining the target speed ratio γ ^* . The other balance thrust Wbl to be realized and the target shift speed when the target gear ratio γ ^* is changed (for example, the primary target shift speed (dXin / dNelmin) and the secondary target shift speed (dXout / dNelmout)) This is the sum of the shift difference thrust ΔW to be realized.

  Here, the differential thrust ΔW when the target gear shift is realized on the primary pulley 42 side, that is, the primary shift differential thrust ΔWin converted to the primary pulley side is (ΔWin> 0) in the upshift state, and the downshift state (ΔWin <0), and in a steady state with a constant gear ratio, (ΔWin = 0). Further, the differential thrust ΔW when realizing the target shift on the secondary pulley 46 side, that is, the secondary shift differential thrust ΔWout converted to the secondary pulley side is (ΔWout <0) in the upshift state, and in the downshift state. If there is (ΔWout> 0), it is (ΔWout = 0) if it is a steady state with a constant gear ratio.

FIG. 5 is a diagram for explaining the thrust required for the shift control. This FIG. 5 shows the primary set when the target upshift is realized on the primary pulley 42 side when the secondary thrust Wout is set so as to realize the belt slip prevention on the secondary pulley 46 side, for example. An example of the thrust Win is shown. In FIG. 5A, before the time point t1 or after the time point t3, the target gear ratio γ ^* is in a constant steady state and ΔWin = 0, so the primary thrust Win is the primary balance thrust Winbl (= Wout / τ). It becomes only. Further, since the target gear ratio γ ^* is in the upshift state from the time t1 to the time t3, the thrust relationship diagram at the time t2 in FIG. 5A shown in FIG. 5B is represented. Further, the primary thrust Win is the sum of the primary balance thrust Winbl and the primary shift difference thrust ΔWin. The shaded portion of each thrust shown in FIG. 5 (b) corresponds to each balance thrust Wbl for maintaining the target speed ratio γ ^* at time t2 in FIG. 5 (a).

FIG. 6 shows that when the secondary pressure sensor 78 is provided only on the secondary pulley 46 side and the primary pressure sensor is not provided on the primary pulley 42 side, the target shift and belt slip can be performed with the minimum necessary thrust. It is a block diagram which shows the control structure for making prevention compatible. In FIG. 6, the target speed ratio γ ^* and the input torque T _IN of the continuously variable transmission 18 are sequentially calculated by, for example, the shift hydraulic pressure control means 132. Specifically, the transmission hydraulic pressure control means 132 determines a post-shift target transmission gear ratio γ ^* 1, which is a transmission gear ratio γ to be achieved after the transmission of the continuously variable transmission 18. For example, the actual output shaft is calculated from the relationship (shift map) obtained and stored in advance between the output shaft rotational speed N _OUT and the target input shaft rotational speed N _IN ^* using the accelerator opening degree A _CC as shown in FIG. A target input shaft rotational speed N _IN ^* is set based on the vehicle state indicated by the rotational speed N _OUT and the accelerator opening degree A _CC . Then, a post-shift target gear ratio γ ^* l (= N _IN ^* / N _OUT ) is calculated based on the target input shaft rotational speed N _IN ^* .

The shift map in FIG. 7 corresponds to a shift condition, and the target input shaft rotational speed N _IN ^* that sets a larger speed ratio γ as the output shaft rotational speed N _OUT is smaller and the accelerator opening degree A _CC is larger is set. It has become. This post-shift target gear ratio γ ^* l is determined within the range of the minimum gear ratio γmin (highest speed gear ratio, highest Hi) and the maximum gear ratio γmax (lowest speed gear ratio, lowest) of the continuously variable transmission 18. It is done. Then, the shift hydraulic pressure control means 132 determines, for example, the gear ratio γ before the shift start and the target gear ratio γ ^* l after the shift from the relationship that has been experimentally set in advance so as to realize a quick and smooth shift. Based on the difference, the target speed ratio γ ^* is determined as the target value of the transitional speed ratio γ during the speed change. For example, the target speed ratio γ ^* that is sequentially changed during a shift is along a smooth curve (for example, a primary delay curve or a secondary delay curve) that changes from the start of the shift toward the post-shift target speed ratio γ ^* l. Is determined as a function of elapsed time. In other words, the shift hydraulic pressure control means 132 sequentially shifts the speed ratio γ before the start of the shift from the speed ratio γ before the start of the shift toward the target speed ratio γ ^* 1 after the shift during the shift of the continuously variable transmission 18. The target gear ratio γ ^* is changed. Further, when determining the target speed ratio γ ^* as a function of the elapsed time, the target speed ratio (primary side target speed (dXin / dNelmin) and secondary side target speed (dXout) during the speed change from the target speed ratio γ ^*. / dNelmout)) is calculated by the target shift speed calculation means 138 described later. For example, when the gear shift is completed and the target gear ratio γ ^* is in a constant steady state, the target gear shift speed becomes zero.

Further, the shift hydraulic pressure control means 132, for example, a pump torque T is an input torque of the turbine torque T _T / torque converter 14 outputs a torque of the torque ratio t (= torque converter 14 of the torque converter 14 to the engine torque T _E The input torque T _IN of the continuously variable transmission 18 is calculated as a torque (= T _E × t) multiplied by _P ). Further, for example, the engine speed N _E and the engine torque T _E are experimentally obtained in advance using the intake air amount Q _AIR (or the corresponding throttle valve opening θ _TH or the like) as a required load for the engine 12 as a parameter. The engine torque T _E is calculated as the estimated engine torque T _E es based on the intake air amount Q _AIR and the engine speed N _E from the relationship (map, engine torque characteristic diagram) shown in FIG. . Alternatively, the engine torque T _E may be, for example, the actual output torque (actual engine torque) T _{E of the} engine 12 detected by a torque sensor or the like. The torque ratio t of the torque converter 14 is the speed ratio e of the torque converter 14 (= the turbine rotational speed N _T that is the output rotational speed of the torque converter 14 / the pump rotational speed N that is the input rotational speed of the torque converter 14. _P (engine speed N _E )), for example, the speed ratio e, torque ratio t, efficiency η, and capacity coefficient C as shown in FIG. From the relationship (map, predetermined operating characteristic diagram of the torque converter 14), the shift hydraulic pressure control means 132 calculates the actual speed ratio e. The estimated engine torque T _E es is calculated so as to represent the actual engine torque T _E itself, and unless otherwise distinguished from the actual engine torque T _E , the estimated engine torque T _E es is converted to the actual engine torque T _E es. It shall be treated as T _E. Therefore, the estimated engine torque T _E es includes the actual engine torque T _E.

  Further, as shown in FIG. 4, the shift hydraulic pressure control means 132 includes, for example, a slip limit thrust calculation unit that calculates a slip limit thrust Wlmt, that is, a slip limit thrust calculation means 134, and a steady thrust calculation unit that calculates a balance thrust Wbl. A steady thrust calculating means 136, a target shift speed calculating section for calculating target shift speeds (primary target shift speed (dXin / dNelmin), secondary target shift speed (dXout / dNelmout)), that is, target shift speed calculating means 138; A differential thrust calculation unit for calculating a shift difference thrust ΔW, that is, a differential thrust calculation unit 140, an F / B control amount calculation unit for calculating a feedback control amount Winfb, that is, an F / B control amount calculation unit 142, and a shift related to feedforward control. A characteristic map learning control unit that performs learning control of the differential thrust characteristic, that is, a characteristic map learning control unit 144 is provided.

In block B1 and block B2 of FIG. 6, the slip limit thrust calculating means 134 calculates the slip limit thrust Wlmt based on, for example, the actual speed ratio γ and the input torque T _IN of the continuously variable transmission 18. Specifically, for example, from the following formula (1) and the following formula (2), the input torque Tin of the continuously variable transmission 18 as the input torque of the primary pulley 42 and the continuously variable as the input torque of the secondary pulley 46 The output torque T _OUT of the transmission 18, the sheave angle α of the variable pulleys 42, 46, the predetermined element-pulley friction coefficient μin on the primary pulley 42 side, the predetermined element-pulley friction coefficient on the secondary pulley 46 side The belt engagement diameter Rin on the primary pulley 42 side uniquely calculated from μout and the actual transmission ratio γ, and the belt engagement diameter Rout on the secondary pulley 46 side calculated uniquely from the actual transmission ratio γ (refer to FIG. 3 above). The secondary pulley side slip limit thrust Woutlmt and the primary pulley side slip limit thrust Winlmt are calculated based on Note that T _OUT = γ × Tin = (Rout / Rin) × Tin. However, in the block B2, the slip limit thrust calculating means 134 calculates the primary pulley side slip limit thrust Winlmt (g) subjected to the lower limit guard process based on the primary pulley side slip limit thrust Winlmt, as will be described later. To do.

Woutlmt = (T _OUT × cos α) / (2 × μout × Rout)
= (Tin × cosα) / (2 × μout × Rin) (1)
Winlmt = (Tin × cosα) / (2 × μin × Rin) (2)

In block B3 and block B6 of FIG. 6, the steady thrust calculating means 136 converts the secondary balance thrust Woutbl corresponding to the primary pulley side slip limit thrust Winlmt (g) subjected to the lower limit guard process and the target secondary thrust Wout ^* , for example. Corresponding primary balance thrust Winbl is calculated respectively. Specifically, the reciprocal SFin ⁻¹ (= Winlmt (g) / Win) of the primary-side safety factor SFin (= Win / Winlmt (g)) and the primary pulley 42 side corresponding to the target speed ratio γ ^* as a parameter. A target calculated sequentially from, for example, a relationship (thrust ratio map) as shown in FIG. 10A, which is experimentally obtained and stored in advance with the thrust ratio τin when the thrust on the secondary pulley 46 side is calculated. The thrust ratio τin is calculated based on the speed ratio γ ^* and the reciprocal SFin ⁻¹ of the primary side safety factor. Then, the steady thrust calculating means 136 calculates the secondary balance thrust Woutbl based on the primary pulley side slip limit thrust Winlmt (g) subjected to the lower limit guard process and the thrust ratio τin from the following equation (3). Further, the steady thrust calculating means 136 uses the target speed ratio γ ^* as a parameter and corresponds to the reciprocal SFout ⁻¹ (= Woutlmt / Wout) of the secondary-side safety factor SFout (= Wout / Woutlmt) and the secondary pulley 46 side. For example, FIG. 10B shows a relationship (thrust ratio map) that is obtained in advance and stored in advance with the thrust ratio τout when the thrust on the primary pulley 42 is calculated. The thrust ratio τout is calculated based on the ratio γ ^* and the reciprocal SFout ⁻¹ of the secondary side safety factor. Then, the steady thrust calculating means 136 calculates the primary balance thrust Winbl based on the target secondary thrust Wout ^* and the thrust ratio τout from the following equation (4). Since the input torque T _IN and the output torque T _OUT are negative values when driven, the reciprocals SFin ⁻¹ and SFout ^{−1 of the} safety factors are negative values when driven. These reciprocal numbers SFin ⁻¹ and SFout ⁻¹ may be calculated sequentially, but if a predetermined value (for example, about 1 to 1.5) is set for each of the safety factors SFin and SFout, the reciprocal numbers are set. May be.

Woutbl = Winlmt (g) × τin (3)
Winbl = Wout ^* / τout (4)

In the block B4 and the block B7 in FIG. 6, the differential thrust calculation means 140, for example, a secondary shift difference thrust ΔWout as a differential thrust ΔW converted on the secondary pulley side when the target shift is realized on the secondary pulley 46 side, for example. A primary shift difference thrust ΔWin is calculated as a differential pulley ΔW converted to the primary pulley when the target shift is realized on the primary pulley 42 side. For example, the primary shift difference thrust ΔWin and the secondary shift difference thrust ΔWout are calculated based on the primary target shift speed (dXin / dNelmin) and the secondary target shift speed (dXout / dNelmout) calculated by the target shift speed calculation means 138. To do. Specifically, the target shift speed calculation means 138 determines the actual vehicle speed V (output shaft rotation speed N _OUT ) and accelerator opening degree A _CC from a predetermined relationship (for example, a shift map as shown in FIG. 7). A target input shaft rotational speed N _IN ^* is set based on the vehicle state shown. Then, based on the target input shaft rotational speed N _IN ^* to calculate the post-shift target speed ratio ^{_{γ * l (= N IN *}} / N OUT), from a predetermined relationship to the post-shift target speed ratio gamma ^* l The corresponding primary side target shift speed (dXin / dNelmin) and secondary side target shift speed (dXout / dNelmout) are calculated.

  Further, specifically, the differential thrust calculation means 140 is, for example, as shown in FIG. 11B, which is experimentally obtained and stored in advance for the secondary target shift speed (dXout / dNelmout) and the secondary shift difference thrust ΔWout. From the relationship shown (difference thrust map), the secondary shift difference thrust ΔWout is calculated based on the secondary target shift speed (dXout / dNelmout) sequentially calculated by the target shift speed calculation means 138. Further, the difference thrust calculation means 140 has a relationship (for example, as shown in FIG. 11A), which is experimentally obtained and stored in advance between the primary target shift speed (dXin / dNelmin) and the primary shift difference thrust ΔWin. From the differential thrust map), the primary shift difference thrust ΔWin is calculated based on the primary target shift speed (dXin / dNelmin) sequentially calculated by the target shift speed calculating means 138.

  Here, in the calculations in the blocks B3 and B4, physical characteristic diagrams that are experimentally obtained and set in advance, such as a thrust ratio map (see FIG. 10) and a differential thrust map (see FIG. 11), are used. Therefore, there are variations in the physical characteristics in the calculation results of the secondary balance thrust Woutbl and the secondary shift difference thrust ΔWout due to individual differences in the hydraulic control circuit 100 and the like. Therefore, when considering such a variation in physical characteristics, the slip limit thrust calculating means 134, for example, thrust on the secondary pulley 46 side based on the primary pulley side slip limit thrust Winlmt (g) subjected to the lower limit guard process, for example. Prior to calculation of the thrust on the secondary pulley 46 side, a predetermined thrust (control margin) Wmgn corresponding to a variation with respect to a physical characteristic related to calculation of (secondary balance thrust Woutbl and secondary shift difference thrust ΔWout) is calculated on the primary pulley side. Add to the slip limit thrust Winlmt (g). Therefore, when considering the variation with respect to the physical characteristics, in the block B3, the steady thrust calculating means 136 adds the control margin Wmgn from the following equation (3) ′ instead of the equation (3), for example. The secondary balance thrust Woutbl is calculated based on the primary pulley side slip limit thrust Winlmt (g) and the thrust ratio τin.

  Woutbl = (Winlmt (g) + Wmgn) × τin (3) ′

Note that the control margin Wmgn is, for example, a constant value (design value) obtained experimentally in advance, and is more variable in the transient state (during gear change) than in the steady state (speed ratio constant state). Since a large amount of (thrust ratio map and physical characteristic diagram of the differential thrust map) is used, it is set to a large value. Further, the variation with respect to the physical characteristics related to the calculation includes, for example, variations in the control hydraulic pressures P _SLP and P _SLS with respect to the control currents to the linear solenoid valves SLP and SLS, variations in the drive circuit that outputs the control current, and control hydraulic pressures. This is different from the deviation of the actual hydraulic pressure with respect to the hydraulic pressure command value of the pulley pressure, such as variations in the actual pulley pressures Pin and Pout with respect to P _SLP and P _SLS (the hydraulic pressure variation and the hydraulic control variation). Although the hydraulic pressure variation is a relatively large value depending on the unit (hard unit such as the hydraulic control circuit 100), the variation with respect to the physical characteristics related to the calculation is an extremely small value compared to the hydraulic pressure variation. . Therefore, adding the control margin Wmgn to the primary pulley side slip limit thrust Winlmt (g) means that the target pulley pressure can be obtained no matter how much the actual pulley pressure varies with respect to the pulley pressure hydraulic pressure command value. Compared with adding a control variation to the command value, deterioration of fuel consumption is suppressed. Further, since the calculations in the blocks B6 and B7 are based on the target secondary thrust Wout ^* , here, the control margin Wmgn is not added to the target secondary thrust Wout ^* prior to the calculation.

Further, the transmission hydraulic pressure control means 132 is, for example, a secondary pulley side transmission control thrust Woutsh obtained by adding a secondary transmission difference thrust ΔWout to a secondary balance thrust Woutbl as a secondary thrust necessary for preventing belt slippage on the primary pulley 42 side. (= Woutbl + ΔWout) is calculated. In block B5 of FIG. 6, the shift hydraulic pressure control means 132 selects the larger one of the secondary pulley side slip limit thrust Woutlmt and the secondary pulley side shift control thrust Woutsh as the target secondary thrust Wout ^* .

Further, the transmission hydraulic pressure control means 132 calculates a primary pulley side shift control thrust Winsh (= Winbl + ΔWin), for example, by adding a primary shift difference thrust ΔWin to the primary balance thrust Winbl. Further, in block B8 of FIG. 6, the F / B control amount calculating means 142 sets the actual speed ratio γ as a target by using a feedback control equation that is obtained and set in advance as shown in the following equation (5), for example. A feedback control amount (F / B control correction amount) Winfb for matching with the gear ratio γ ^* is calculated. In this equation (5), Δγ is a gear ratio deviation (= γ ^* −γ) between the target gear ratio γ ^* and the actual gear ratio γ, KP is a predetermined proportionality constant, KI is a predetermined integral constant, and KD is a predetermined speed. Differential constant. Then, the transmission hydraulic pressure control means 132 sets, for example, a value (= Winsh + Winfb) corrected by feedback control based on the transmission ratio deviation Δγ for the primary pulley side transmission control thrust Winsh as the target primary thrust Win ^* .

  Winfb = KP × Δγ + KI × (∫Δγdt) + KD × (dΔγ / dt) (5)

In this way, the blocks B1 to B5 function as a secondary target thrust calculation unit that sets the target secondary thrust Wout ^*, that is, the secondary target thrust calculation means 150. The blocks B6 to B8 function as a primary target thrust calculation unit that sets a target primary thrust Win ^*, that is, a primary target thrust calculation unit 152.

In block B9 and block B10 of FIG. 6, the shift hydraulic pressure control means 132 converts, for example, a target thrust into a target pulley pressure. Specifically, the transmission hydraulic pressure control means 132 sets the target secondary thrust Wout ^* and the target primary thrust Win ^* to the target secondary pressure Pout ^* (= Wout ^* /) based on the pressure receiving areas of the hydraulic cylinders 46c and 42c. 46c) and the target primary pressure Pin ^* (= Win ^* / 42c pressure receiving area). The transmission hydraulic pressure control means 132 sets the target secondary pressure Pout ^* and the target primary pressure Pin ^* as the secondary command pressure Pouttgt and the primary command pressure Pintgt.

The shift hydraulic pressure control means 132 outputs the primary command pressure Pintgt and the secondary command pressure Pouttgt to the hydraulic control circuit 100 as the hydraulic control command signal S _CVT so that, for example, the target primary pressure Pin ^* and the target secondary pressure Pout ^* are obtained. To do. In accordance with the hydraulic control command signal S _CVT , the hydraulic control circuit 100 operates the linear solenoid valve SLP to adjust the primary pressure Pin, and operates the linear solenoid valve SLS to adjust the secondary pressure Pout.

In addition, the shift hydraulic pressure control means 132 detects the secondary pressure Pout detected by the secondary pressure sensor 78 as a target secondary pressure in order to compensate for, for example, a hydraulic pressure variation (variation in hydraulic control) on the secondary pulley 46 side. to match the Pout ^*, corrects the secondary command pressure Pouttgt by feedback control based on the secondary pressure detected value of Pout and the target secondary pressure Pout ^* deviation between ΔPout (= Pout ^* -Pout detection value). In the hydraulic control circuit 100 of the present embodiment, since the hydraulic sensor is not provided on the primary pulley 42 side, feedback control as on the secondary pulley 46 side based on the deviation between the detected value of the pulley pressure and the actual value is provided. Therefore, the primary command pressure Pintgt cannot be corrected. However, in this embodiment, for example, a value (= Winsh + Winfb) corrected by feedback control so that the actual gear ratio γ matches the target gear ratio γ ^* in the block B8 is set as the target primary thrust Win ^* . The variation in hydraulic pressure on the primary pulley 42 side can be compensated.

As described above, the transmission hydraulic pressure control means 132 feedback-controls the difference between the target transmission ratio γ ^* and the actual transmission ratio γ in the transmission pressure control for changing the transmission ratio γ of the continuously variable transmission 18. On the other hand, the hydraulic pressure that determines the thrust in the variable pulleys 42 and 46 is feedforward controlled based on a predetermined shift difference thrust characteristic. That is, with respect to the calculation of the shift difference thrust ΔW by the difference thrust calculation means 140, for example, as shown in FIG. 4, a shift is made based on the target shift speed from a characteristic map 128 as a shift difference thrust characteristic stored in advance in the storage device 126. Control for calculating (derived) the differential thrust ΔW is performed. For example, as shown in FIG. 11 described above, the characteristic map 128 is a relationship (shift difference) that has been experimentally determined and stored between the target shift speeds dXin / dNelmin, dXout / dNelmout and the shift difference thrusts ΔWin, ΔWout. A thrust characteristic map and a differential thrust map), which are preferably obtained experimentally and stored corresponding to each of the primary pulley 42 and the secondary pulley 46. Alternatively, only one of the primary pulley 42 and the secondary pulley 46 has a shift differential thrust characteristic as shown in FIG. 11, and this embodiment will be described in detail below only with respect to the shift pressure control relating to one of the variable pulleys. These controls may be applied. In the following description, the control on the primary pulley 42 side will be mainly described.

  The characteristic map learning control means 144 performs learning control of the shift difference thrust characteristic related to the feedforward control. That is, the characteristic map 128 for performing the feedforward control for calculating (derived) the shift difference thrust ΔW based on the target shift speed calculated by the target shift speed calculating means 138 is corrected according to the variation of each unit ( Change) learning control. Specifically, based on the control amount in the feedback control in the shift pressure control performed in the past, that is, based on the feedback control amount (F / B control correction amount) Winfb calculated by the feedback control amount calculation means 138, Learning control of shift difference thrust characteristics related to feedforward control is performed.

  FIG. 12 is a diagram for explaining the learning control of the characteristic map 128 by the characteristic map learning control unit 144, and illustrates the relationship on the upshift side of the primary pulley 42 (corresponding to the right side in FIG. 11A). ing. In FIG. 12, the shift difference thrust characteristic (characteristic map) before learning is indicated by a solid line, and the shift difference thrust characteristic after learning is indicated by a broken line. As shown in FIG. 12, the characteristic map learning control unit 144 is, for example, the feedback control amount calculation unit as learning control of the shift difference thrust characteristic based on the control amount of the feedback control in the shift pressure control performed in the past. The feedback control amount (F / B control correction amount) Winfb calculated by 138 is converted into the shift difference thrust dWco, and the characteristic map 128 is corrected based on the shift difference thrust dWco corresponding to the feedback control amount. That is, control for correcting (changing) the characteristic map 128 stored in the storage device 126 so that a shift difference thrust larger (or smaller) by the converted value dWco is derived corresponding to the same target shift speed. (In the example shown in FIG. 12, correction for adding the converted value dWco to the characteristic map) is performed.

  The characteristic map learning control unit 144 preferably performs the learning when the absolute value of the target shift speed calculated by the target shift speed calculation unit 138 is less than a predetermined threshold value (during slow shift). Take control. That is, at the time of a slow shift where the change amount dγ (= dγ / dt) of the transmission ratio γ per unit time to the sheave position movement amount (dX / dNelm) per element (block) of the transmission belt 48 is relatively small. The characteristic map learning control means 144 performs learning control of the shift map 128. In other words, when the absolute value of the target shift speed calculated by the target shift speed calculating means 138 is equal to or greater than the above threshold value (during sudden shift), learning is not performed (learning is prohibited or not executed).

In the shift pressure control by the continuously variable transmission 18, the ideal relationship between the target shift speed and the shift difference thrust does not necessarily have a proportional relationship in a region where the shift speed is relatively small. However, in such a region where the shift speed is relatively low, the unit-to-unit variation is larger than the region where the shift speed is relatively large. It is necessary to increase the control gain. Further, as described above, the feedback control of the present embodiment performs the shift pressure control based on the deviation between the target speed ratio γ ^* and the actual speed ratio γ, but the deviation is large when the feedback control gain is large. When it is relatively small, overcorrection occurs, and there is a possibility that shift hunting occurs. Therefore, by performing the learning control at the time of a slow shift where the absolute value of the target shift speed is less than a predetermined threshold value, occurrence of such a problem can be suitably suppressed.

  Further, the characteristic map learning control means 144 is preferably the speed change pressure control of the previous time (the speed change pressure control performed before the target control is not necessarily the previous control). When the control amount in the feedback control is equal to or greater than a predetermined threshold value, learning control of the shift difference thrust characteristic related to the feedforward control is executed based on the control amount. That is, when the absolute value of the feedback control amount (F / B control correction amount) Winfb calculated by the feedback control amount calculation means 138 is equal to or larger than the threshold value, it is based on the shift difference thrust dWco corresponding to the feedback control amount. Then, learning control for correcting the characteristic map 128 is performed. In other words, when the control amount in the feedback control is less than a predetermined threshold, the learning is not performed (learning is prohibited or not executed).

FIG. 13 is a time chart illustrating various waveforms during the shift pressure control of the continuously variable transmission 18, and the waveform when the learning control of the present embodiment is performed is indicated by a solid line, and the learning control of the present embodiment is performed. The waveform in the absence of this is indicated by a broken line, and the target value of the gear ratio and the input rotation speed is indicated by a dashed line. Further, the feedback control amount shown at the bottom indicates a waveform in the previous shift pressure control. In the conventional control indicated by the broken line in FIG. 13, the hydraulic pressure corresponding to the transmission differential thrust characteristic (transmission map 128) is corrected by feedforward control, and the difference between the target transmission ratio γ ^* and the actual transmission ratio γ is corrected by feedback control. However, due to the variation in the gear shift difference thrust characteristics of each unit, it differs from the planned gear shift thrust characteristics (ideal for each unit), and the amount of correction by feedback control increases. Due to the response delay of the feedback control, the shift speed changes between the initial shift stage and the latter half of the shift. That is, the driver may feel uncomfortable due to a change in the shift speed caused by an increase in the burden of feedback control. On the other hand, according to the learning control of the present embodiment, the shift difference thrust characteristic is changed using the shift difference thrust dWco corresponding to the feedback control amount (indicated by the area A of the hatched portion in FIG. 13) at the previous shift pressure control as a learning value. Thus, since the correction value of the previous feedback control is reflected in advance in the feedforward control, the burden of the feedback control (correction amount) can be reduced, and a change in the shift speed can be suitably prevented. In addition, a hydraulic pressure sensor is provided for detecting the actual primary pressure Pin acting on the primary pulley 42 (primary hydraulic cylinder 42c) by changing the shift differential thrust characteristic using the feedback control amount Winfb at the time of shifting as a learning value. Learning control is possible even in a configuration that is not, and suitable shift control can be realized without causing the driver to feel uncomfortable.

  The characteristic map learning control unit 144 preferably executes learning control for increasing the hydraulic pressure with respect to the initially set characteristic, regarding the learning of the shift difference thrust characteristic related to the feedforward control. . That is, as a result of learning, a learning control in which the shift differential thrust ΔW corresponding to a predetermined target shift speed is corrected (changed) to the side that increases the hydraulic pressure supplied to the primary pulley 42 (primary hydraulic cylinder 42c). Execute. On the other hand, the learning control is not performed to reduce the hydraulic pressure with respect to the initially set characteristics (learning is prohibited or not executed). That is, as a result of learning, learning control in which the shift difference thrust ΔW corresponding to a predetermined target shift speed is corrected (changed) to the side that reduces the hydraulic pressure supplied to the primary pulley 42 (primary hydraulic cylinder 42c). Does not execute.

14 and 15 are diagrams for explaining the learning control of the characteristic map 128 by the characteristic map learning control means 144, and the relationship on the upshift side in the primary pulley 42 (corresponding to the right side in FIG. 11A). FIG. 14 illustrates the downshift-side relationship (corresponding to the left side in FIG. 11A). As shown in FIGS. 14 and 15, when the absolute value of the target shift speed calculated by the target shift speed calculating means 138 is less than a predetermined threshold value V _A (at the time of slow shift), the target shift speed is calculated. Compared with the case where the absolute value of the speed is equal to or greater than a predetermined threshold _VA (during sudden shift), the unit-to-unit variation greatly affects, and the ideal relationship between the target shift speed and the shift difference thrust is not necessarily proportional. Therefore, the feedforward control should be learned in such a region. However, for example, if an erroneous learning is performed on the side where the hydraulic pressure of the primary pulley 42 (primary hydraulic cylinder 42c) is removed, there is a possibility that the transmission belt 48 may slip. However, the control on the side where the hydraulic pressure is released is not executed.

  In the relationship on the upshift side in the primary pulley 42 shown in FIG. 14, the upper side of the solid line indicating the initial setting characteristics (the side of the relationship indicated by the alternate long and short dash line) corresponds to the side where the hydraulic pressure is applied, and the lower side ( The side of the relationship shown) corresponds to the side from which hydraulic pressure is released. Therefore, while learning is performed to correct the characteristic to the upper side of the solid line indicating the initial characteristic (upper left to the lower right hatched area), the lower side of the solid line indicating the initial characteristic (upper right to lower left diagonal line). Learning to correct the characteristics toward the range side is not executed. Further, in the relationship on the downshift side in the primary pulley 42 shown in FIG. 15, the upper side of the solid line indicating the characteristics of the initial setting (the side of the relationship indicated by the two-dot chain line) corresponds to the side from which the hydraulic pressure is released, The side indicated by the chain line) corresponds to the side on which hydraulic pressure is applied. Accordingly, learning for correcting the characteristic to the upper side of the solid line indicating the initial setting characteristic (the oblique line range side from the upper right to the lower left) is not executed, while the lower side of the solid line indicating the initial setting characteristic (from upper left to lower right). The learning for correcting the characteristic is executed.

  FIG. 16 is a flowchart for explaining a main part of the shift pressure control of the continuously variable transmission 18 through the hydraulic control circuit 100 by the electronic control unit 50, and is repeatedly executed at a predetermined cycle. . In this embodiment, the control shown in FIG. 16 and the control shown in FIG. 17 which will be described later will be described separately. However, these controls can be executed concurrently in the same shift pressure control. It may be executed by being integrated with the control.

First, in step (hereinafter, step is omitted) SA1, the target input shaft rotation is based on the vehicle state indicated by the actual vehicle speed V (output shaft rotational speed N _OUT ) and accelerator opening degree A _CC from a predetermined relationship. A speed N _IN ^* is set, and based on the target input shaft rotational speed N _IN ^* , the post-shift target speed ratio γ ^* l and the primary target shift speed (dXin / dNelmin corresponding to the post-shift target speed ratio γ ^* l ), The secondary side target shift speed (dXout / dNelmout) is calculated. Next, in SA2, the required shift difference thrust ΔW is calculated by feedforward control based on the target shift speed calculated in SA1 from a predetermined shift map (shift difference thrust characteristic). Next, at SA3, the speed difference thrust ΔW is corrected (controlled) by feedback control from the speed ratio deviation Δγ between the target speed ratio γ ^* and the actual speed ratio γ. Next, in SA4, it is determined whether the feedback control amount Winfb in SA3 is larger than a predetermined threshold value. If the determination at SA4 is affirmative, at SA5, learning control of the shift difference thrust characteristic relating to the calculation of the shift difference thrust ΔW is performed based on the control amount Winfb in the feedback control at SA3, and then SA6 is performed. Although the following processing is executed, if the determination in SA4 is negative, it is determined in SA6 whether or not the shift has been completed, for example, the post-shift target gear ratio γ ^* has been achieved. If the determination at SA6 is negative, the processing after SA1 is executed again. If the determination at SA6 is affirmative, the routine is terminated.

  FIG. 17 is a flowchart for explaining a main part of another example of the shift pressure control of the continuously variable transmission 18 through the hydraulic control circuit 100 by the electronic control unit 50, and is repeatedly executed at a predetermined cycle. Is.

First, at SB1, the feedback control amount Winfb is calculated from the gear ratio deviation Δγ between the target gear ratio γ ^* and the actual gear ratio γ. Next, at SB2, it is determined whether or not the shift is completed, for example, after the post-shift target gear ratio γ ^* is achieved. If the determination at SB2 is affirmed, this routine is terminated accordingly. If the determination at SB2 is negative, the slow shift in which the target shift speed is less than a predetermined threshold value at SB3. It is determined whether it is time. When the determination at SB3 is negative, the processing after SB6 is executed. However, when the determination at SB3 is positive, the feedback control amount Winfb calculated at SB1 is fed forward at SB4. It is determined whether or not the correction is to a side larger than the initial value of the shift difference thrust characteristic related to the control (a side to increase the hydraulic pressure supplied to the variable pulley). When the determination at SB4 is negative, the processing after SB6 is executed. When the determination at SB4 is affirmative, at SB5, the shift is performed based on the control amount Winfb in the feedback control of SB1. After the learning control of the shift difference thrust characteristic related to the calculation of the difference thrust ΔW is performed, in SB6, the shift difference thrust based on the target shift speed from the shift difference thrust characteristic (learned in the previous shift pressure control). After the feed forward control for calculating ΔW is performed, this routine is terminated.

  In the control shown in FIGS. 16 and 17, SA1 is the operation of the target shift speed calculation means 138, SA2 and SB6 are the operations of the differential thrust calculation means 140, and SA3 and SB1 are the feedback control amount calculation means 142. SA5 and SB5 correspond to the operation of the characteristic map learning control means 144, respectively.

As described above, according to the present embodiment, in the speed change pressure control, the difference between the target speed ratio γ ^* and the actual speed ratio γ is feedback-controlled, while the variable pulley is based on a predetermined speed difference thrust characteristic. The hydraulic pressure that determines the thrust in 42 and 46 is feedforward controlled, and based on the control amount Winfb in the feedback control in the shift pressure control performed in the past, learning control of the shift difference thrust characteristic related to the feedforward control Therefore, by changing the shift difference thrust characteristic using the feedback control amount Winfb at the time of shift as a learning value, feed forward control corresponding to the shift difference thrust characteristic can be performed for each unit. An increase in speed change can be suppressed, and a sense of discomfort to the driver can be suitably suppressed. That is, it is possible to provide the hydraulic control device (electronic control device 50) of the continuously variable transmission 18 that improves the drivability during the shift pressure control.

  Further, regarding the learning control of the shift difference thrust characteristic related to the feedforward control, the learning control to the side to increase the hydraulic pressure is executed with respect to the initial setting characteristic, but the learning control to the side to decrease the hydraulic pressure is performed. Therefore, the shift difference thrust characteristic can be changed with the feedback control amount Winfb at the time of shifting as a learning value while suppressing slippage of the transmission belt 48 due to erroneous learning.

Further, regarding the learning control of the shift difference thrust characteristic related to the feedforward control, the feedforward is performed when a target shift speed (absolute value) in the shift pressure control is less than a predetermined threshold value V _A (during a slow shift). The learning control of the shift difference thrust characteristic related to the control is executed, but when it is equal to or higher than the threshold value _VA (at the time of sudden shift), the learning control of the shift difference thrust characteristic related to the feedforward control is not executed. Therefore, the unit-to-unit variation greatly affects, and the ideal relationship between the target shift speed and the shift difference thrust ΔW does not necessarily have a proportional relationship. be able to.

  Further, regarding the learning control of the shift difference thrust characteristic related to the feedforward control, when the control amount Winfb in the feedback control in the previous shift pressure control is equal to or greater than a predetermined threshold value, the control amount Winfb is based on the control amount Winfb. Since the learning control of the shift difference thrust characteristic related to the feedforward control is executed, the learning control of the shift difference thrust characteristic using the feedback control amount Winfb at the time of the shift as a learning value is performed in an efficient and practical manner. be able to.

  Further, by configuring the hydraulic pressure control circuit 100 so as to independently control the pulley pressure applied to the primary pulley 42 as the input side variable pulley and the secondary pulley 46 as the output side variable pulley, the input side thrust and Each output side thrust is controlled directly or indirectly.

  The preferred embodiments of the present invention have been described in detail with reference to the drawings. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the present invention. Is.

  18: belt type continuously variable transmission for vehicle, 42: primary pulley (input side variable pulley), 46: secondary pulley (output side variable pulley), 48: transmission belt, 50: electronic control unit, 128: characteristic map (shift) Differential thrust characteristics)

Claims (4)

Regarding a belt-type continuously variable transmission having an input-side variable pulley and an output-side variable pulley with variable effective diameters, and a transmission belt wound between the pair of variable pulleys, the pair of variable pulleys A vehicular belt type continuously variable transmission hydraulic control device that performs a shift pressure control to change a transmission ratio of the belt type continuously variable transmission by controlling a hydraulic pressure that determines a thrust in each
In the transmission pressure control, feedback control is performed on the difference between the target transmission ratio and the actual transmission ratio, while feed-forward control is performed on the hydraulic pressure that determines the thrust in the variable pulley based on a predetermined transmission difference thrust characteristic.
A belt type continuously variable transmission for a vehicle that performs learning control of a shift difference thrust characteristic related to the feedforward control based on a control amount in the feedback control in a shift pressure control performed in the past. Hydraulic control device.   Regarding the learning control of the shift difference thrust characteristic related to the feedforward control, the learning control to the side to increase the hydraulic pressure is executed with respect to the initial setting characteristic, but the learning control to the side to decrease the hydraulic pressure is prohibited. The hydraulic control device for a belt type continuously variable transmission for a vehicle according to claim 1.   3. The learning control according to claim 1, wherein the learning control is executed when a shift speed of the shift pressure control is less than a predetermined threshold regarding the learning control of the shift difference thrust characteristic related to the feedforward control. Hydraulic control device for a belt type continuously variable transmission for a vehicle.   Regarding the learning control of the shift difference thrust characteristic related to the feedforward control, when the control amount in the feedback control in the previous shift pressure control is equal to or greater than a predetermined threshold, the feedforward control is performed based on the control amount. The hydraulic control device for a belt type continuously variable transmission for a vehicle according to any one of claims 1 to 3, wherein learning control of the shift difference thrust characteristic is executed.

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