JPH05240331A - Hydraulic pressure control device of vehicle power transmission device - Google Patents

Abstract

PURPOSE:To improve the accuracy in controlling the torque capacity control pressure by selecting a feedback control means and a feedforward control means according to the stable condition/transitional condition, and controlling a pressure-regulating means by the obtained control signal based on the specified formula in the respective control means. CONSTITUTION:While a vehicle is driven, the target pressure of the torque capacity control pressure related to the transmitted torque capacity of a vehicle's power transmission device is determined based on the vehicle condition in a target pressure determining means. A pressure-regulating means of the torque capacity control pressure is controlled by a control means so that the deviation between this target pressure and the actual torque capacity control pressure may be eliminated. The control means is provided with a feedback control means to generate the control signal based on the formula including the integral terms to calculate the control quantity corresponding to the integrated value of the deviation, and a feedforward control means to generate the control signal based on the formula including the feedforward value and the learning-corrected value to obtain the target pressure, and these control means are selectively used by a switching means according to the stable condition/transitional condition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic control system for a vehicle power transmission device.

[0002]

2. Description of the Related Art In vehicle power transmission devices such as a stepped automatic transmission known as a so-called A / T, a continuously variable transmission known as a so-called CVT, and a friction automatic clutch, a friction clutch, a transmission belt, etc. The transmission torque capacity control pressure is used so that the frictional engagement force of the power transmission member becomes necessary and sufficient. This transmission torque capacity control pressure is sometimes referred to as line pressure, for example, and is used as the source pressure of an actuator for pressing members that transmit power to each other. Some are directly related.

In a conventional hydraulic control device for a power transmission device for a vehicle, a target pressure determining means for determining a target pressure of a torque capacity control pressure related to a transmission torque capacity of the power transmission device, and a control signal. Pressure adjusting means for adjusting the torque capacity control pressure based on, and a control means for outputting the control signal so as to eliminate the deviation between the actual torque capacity control pressure and the target pressure, For example, the transmission torque capacity corresponding to the input torque of the power transmission device can be obtained. For example, the hydraulic control device for a continuously variable transmission for a vehicle described in the specification of Japanese Patent Application No. 2-255757 filed by the applicant of the present application is that.

[0004]

By the way, in the above-mentioned conventional hydraulic control device, the torque control is performed by the feedback control means for determining the control operation amount from the feedback control formula based on the deviation between the actual torque capacity control pressure and the target pressure. The control pressure, that is, the line pressure is controlled. However, when the accelerator operation amount of the vehicle is changed, when the gear shift of the automatic transmission is executed, or when the shift control valve, the lockup clutch control valve, or the like is duty-driven, the disturbance is large. In such a transient state of the torque capacity control pressure, the feedback control of the torque capacity control pressure becomes unstable.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to control the hydraulic pressure of a vehicle power transmission device in which the control of the torque capacity control pressure is stable even when the torque capacity control pressure is transient. It is to provide a control device.

[0006]

The gist of the present invention for achieving such an object is related to the transmission torque capacity of a vehicle power transmission device as shown in the gist of the invention of FIG. Target pressure determining means for determining the target pressure of the torque capacity control pressure based on the vehicle state, pressure adjusting means for adjusting the torque capacity control pressure based on a control signal, actual torque capacity control pressure and the target pressure Is a hydraulic control device for a vehicle power transmission device comprising a control means for outputting the control signal so that the deviation is eliminated, wherein the control means is (a) a control corresponding to an integral value of the deviation. Feedback control means for generating the control signal based on a feedback control equation including an integral term for calculating the amount, and (b) a feedforward value for obtaining the target pressure and for correcting the feedforward value. Feedforward control means for generating the control signal based on a feedforward control equation including a learning correction value, and (c) in the stable state of the torque capacity control pressure, the feedback control means is selected, and the torque capacity control pressure In the transient state, a switching means for selecting the feedforward control means, and (d) the learning correction value of the feedforward control expression is corrected based on the value of the integral term of the feedback control expression in the stable state of the torque capacity control pressure. And learning means for doing so.

[0007]

With this configuration, the feedback control means is selected by the switching means in the stable state of the torque capacity control pressure, and the feedforward control means is selected in the transient state of the torque capacity control pressure. Therefore, when the accelerator operation amount of the vehicle is changed, when the gear shift of the automatic transmission is executed, or when the disturbance is large such as when the shift control valve, the lockup clutch control valve, etc. are duty driven. In the transient state of the torque capacity control pressure, the torque capacity control pressure is stably controlled by the feedforward control.

Further, the learning means corrects the learning correction value of the feedforward control formula based on the value of the integral term of the feedback control formula in the stable state of the torque capacity control pressure. The accuracy of the torque capacity control pressure control in the open loop control is improved, and a value close to the target pressure is preferably obtained.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. In FIG. 2, the power of the engine 10 is
Fluid coupling with lockup clutch 12, belt type continuously variable transmission (hereinafter referred to as CVT) 14, forward / reverse switching device 1
6, the intermediate gear device 18, and the differential gear device 20 are transmitted to the drive wheels 24 connected to the drive shaft 22.

The fluid coupling 12 includes a pump impeller 28 connected to a crankshaft 26 of the engine 10 and a CVT 1.
4, a turbine impeller 32 fixed to the input shaft 30 and rotated by oil from the pump impeller 28, a lockup clutch 36 fixed to the input shaft 30 via a damper 34, an engagement side oil chamber 33, and The release side oil chamber 35 is provided. The fluid coupling 12 is constantly filled with hydraulic oil. For example, when the vehicle speed becomes a predetermined value or higher, or when the rotational speed difference between the pump impeller 28 and the turbine impeller 32 becomes a predetermined value or lower, the engagement side oil When the hydraulic oil is supplied to the chamber 33 and the hydraulic oil flows out from the release side oil chamber 35, the lockup clutch 36 is engaged and the crankshaft 26 and the input shaft 30 are directly connected. On the contrary, when the vehicle speed becomes equal to or lower than the predetermined value, or when the rotational speed difference becomes equal to or higher than the predetermined value, the hydraulic oil is supplied to the release side oil chamber 35 and the hydraulic oil flows out from the engagement side oil chamber 33. As a result, the lockup clutch 36 is released.

The CVT 14 is equipped with variable pulleys 40 and 42 of the same diameter provided on the input shaft 30 and the output shaft 38 thereof, respectively, and a transmission belt 44 wound around the variable pulleys 40 and 42. Variable pulley 40
And 42 are fixed rotary bodies 46 and 48 fixed to the input shaft 30 and the output shaft 38, respectively, and movable bodies provided on the input shaft 30 and the output shaft 38, respectively, so as to be movable in the axial direction and non-rotatable around the shaft. Rotating bodies 50 and 52
The movable rotary bodies 50 and 52 are moved by the primary side hydraulic cylinder 54 and the secondary side hydraulic cylinder 56 that function as hydraulic actuators, thereby changing the V groove width, that is, the hanging diameter (effective diameter) of the transmission belt 44. Thus, the gear ratio γ of the CVT 14 (= rotational speed N _in of the input shaft 30 / rotational speed N _out of the output shaft 38) is changed. Since the variable pulleys 40 and 42 have the same diameter, the hydraulic cylinders 54 and 56 have the same pressure receiving area. Normally, the pressure of the hydraulic cylinders 54 and 56 located on the driven side is operated exclusively to maintain the tension of the transmission belt 44 at an optimum level.

The forward / reverse switching device 16 is a well-known double-pinion type planetary gear mechanism, and a pair of planetary gears 62 and 64 are rotatably supported by a carrier 60 fixed to an output shaft 58 of the planetary gear mechanism and mesh with each other. A sun gear 66 that is fixed to the input shaft (output shaft of the CVT 14) 38 of the forward / reverse switching device 16 and that meshes with the planet gear 62 on the inner circumference side; and a ring gear 6 that meshes with the planet gear 64 on the outer circumference side.
8, the reverse brake 70 for stopping the rotation of the ring gear 68, the carrier 60, and the forward / reverse switching device 16
And a forward clutch 72 that connects the input shaft 38 of FIG. Reverse brake 70 and forward clutch 72
Is a friction engagement device of the type that is hydraulically actuated, and when they are not engaged together, the forward / reverse switching device 1
6 is brought to a neutral state and power transmission is cut off. But,
When the forward clutch 72 is engaged, the output shaft 38 of the CVT 14 and the output shaft 58 of the forward / reverse switching device 16 are directly connected to each other to transmit power in the vehicle forward direction. When the reverse brake 70 is engaged, the rotational direction is reversed between the output shaft 38 of the CVT 14 and the output shaft 58 of the forward / reverse switching device 16, so that power in the reverse direction of the vehicle is transmitted.

FIG. 3 shows in detail the essential parts of the hydraulic control circuit of FIG. 2 for controlling the vehicle power transmission device. Other parts are the same as those described in, for example, JP-A-2-212658.

In FIG. 3, an oil pump 74 constitutes a hydraulic pressure source of the present hydraulic pressure control circuit, and the hydraulic coupling 1
By being integrally connected to the second pump impeller 28, the crankshaft 26 is constantly driven to rotate. The oil pump 74 sucks the working oil that has flowed back into an oil tank (not shown) through the strainer 76, and sucks the working oil that is returned through the return oil passage 78 to pump it to the first line oil passage 80. . In the present embodiment, the hydraulic oil in the first line oil passage 80 is leaked to the return oil passage 78 and the lockup clutch pressure oil passage 92 by the relief type first pressure regulating valve 100, so that the first line oil passage 80. The first line hydraulic pressure P ₁₁ is adjusted. Further, the second line oil pressure P _l2 in the second line oil passage 82 is adjusted by reducing the first line oil pressure P _l1 by the second pressure adjusting valve 102 of the pressure reducing valve type. The second line pressure P _l2, since the pressure is adjusted to control the clamping force against the transmission belt 44,
This corresponds to the belt tension control pressure of this embodiment, that is, the torque capacity control pressure of the CVT 14.

First, the second pressure regulating valve 102 will be described. The second pressure regulating valve 102 includes a spool valve element 110 that opens and closes between the first line oil passage 80 and the second line oil passage 82, a spring seat 112, a return spring 114, and a plunger 116. A first land 118, a second land 120, and a third land 122 having a larger diameter are sequentially formed on the shaft end of the spool valve 110. Second
Lands 120 and between the third land 122 and the introduced chamber 126 is provided through the aperture 124 and the second line pressure P _l2 as a feedback pressure, spool 1
10 is urged in the valve closing direction by the second line hydraulic pressure _P12 . A chamber 130 is provided on the end surface side of the first land 118 of the spool valve element 110, through which a gear ratio specific pressure Pr, which will be described later, is introduced via a throttle 128, and the spool valve element 110 is closed by the gear ratio specific pressure Pr. It is designed to be biased in the valve direction. In the second pressure regulating valve 102, the biasing force of the return spring 114 in the valve opening direction is applied to the spool valve element 110 via the spring seat 112. Further, a chamber 132 for applying a later-described throttle pressure P _th is provided on the end surface side of the plunger 116, and the spool valve element 110 is biased in the valve opening direction by the throttle pressure P _th. There is. Then, the first land 118 and the second land 12 of the spool valve 110
Between 0 and 0, there is provided a chamber 136 to which an output signal pressure P _solL output from a linear valve 180 described later is introduced,
The spool valve element 110 is biased in the valve closing direction by the gear ratio specific pressure Pr.

Therefore, the pressure receiving area of the first land 118 is A ₁ , the cross sectional area of the second land 120 is A ₂ , the cross sectional area of the third land 122 is A ₃ , and the pressure receiving area of the land 117 of the plunger 116 is A. ₄ , return spring 11
When the biasing force of 4 is W, the spool valve element 110 is basically balanced at a position where the following mathematical formula 1 is established. That is, when the spool valve element 110 is moved according to Equation 1, the hydraulic oil in the first line oil passage 80 guided to the port 134a is transferred to the port 134a.
The state in which it is made to flow into the second line oil passage 82 via b and the second line oil passage 82 which is guided to the port 134b.
Hydraulic oil inside is repeated and the state flows to the drain port 134c communicating with the drain is the second line pressure P _l2 is generated. The second line oil passage 82 is a relatively closed system, and the second pressure regulating valve 102 is shown in FIG. 4 by reducing the first line oil pressure P ₁₁ which is a relatively high oil pressure as described above. It creates pressure.

[0017]

[Equation 1]

The first pressure regulating valve 100 includes a spool valve 14
0, spring seat 142, return spring 14
4, the first plunger 146, and the second plunger 14 having the same diameter as the second land 155 of the first plunger 146.
8 are provided respectively. The spool valve 140 is the first
The port 150a communicating with the line oil passage 80 is opened and closed between the drain port 150b or 150c, and the first line hydraulic pressure P _l1 as a feedback pressure acts on the end surface of the first land 152 through the throttle 151. A chamber 153 is provided for allowing the spool valve element 140 to be urged in the valve opening direction by the first line hydraulic pressure P _l1 . A chamber 156 for guiding the throttle pressure P _th is provided between the first land 154 and the second land 155 of the first plunger 146 provided coaxially with the spool valve element 140, and the second land is also provided. 155
Between the second plunger 148 and the second plunger 148, the chamber 1 for guiding the hydraulic pressure P _in in the primary hydraulic cylinder 54 through the oil passage 161.
57 is provided, further to the end face of the second plunger 148 and chamber 158 is provided for guiding the second line pressure P _l2. The urging force of the return spring 144 is applied to the spool valve 14 via the spring seat 142.
0 in the valve closing direction, the spool valve 14
0, the pressure receiving area of the first land 152 is A ₅ , the cross-sectional area of the first land 154 of the first plunger 146 is A ₆ , the cross-sectional area of the second land 155 and the second plunger 148 is A ₇ ,
When the biasing force of the return spring 144 is W, the spool valve element 140 is balanced at a position where the following expression 2 is established, and the first line hydraulic pressure P ₁₁ is regulated.

[0019]

[Equation 2]

In the first pressure regulating valve 100, the hydraulic pressure P _{in in the} primary hydraulic cylinder 54 is the second line hydraulic pressure P _l2 (P _l2 = steady-state hydraulic pressure P _out in the secondary hydraulic cylinder 56).
If it is higher than the above, the first plunger 146 and the second plunger 148 are separated from each other, and the thrust due to the oil pressure P _{in in the} primary side hydraulic cylinder 54 acts in the valve closing direction of the spool valve element 140. Hydraulic pressure in side hydraulic cylinder 54 P _in
Is lower than the second line oil pressure _Pl2 , the first plunger 146 and the second plunger 148 come into contact with each other, and thus the thrust _force by the second line oil pressure _Pl2 acting on the end surface of the second plunger 148. Acts in the valve closing direction of the spool valve element 140. That is, the primary hydraulic cylinder 54
The second plunger 148 that receives the internal oil pressure P _in and the second line oil pressure P 12 _{applies the} acting force based on the higher one of the oil pressures in the valve closing direction of the spool valve 140. The first land 15 of the spool valve 140
The chamber 160 provided between the second land 159 and the second land 159 is open to the drain.

The throttle pressure P _th is a signal pressure representing the throttle valve opening θ _th as shown in FIG. 5, and is a throttle opening detection valve (not shown) which is operated in association with the rotational position of the throttle cam. Is generated from. Further, the gear ratio pressure P _r is the gear ratio γ of the CVT 14 as shown in FIG.
Is generated from a gear ratio detection valve (not shown) that is operated in relation to the axial position of the movable rotary body 50 or 52. The transmission ratio detecting valve, since those which generate speed ratio pressure P _r by changing the relief amount of hydraulic oil in the second line pressure P _l2 supplied through the orifice from the second line oil passage 82, shift The specific pressure P _r is limited to a value _{equal to} or higher than the second line hydraulic pressure P 12 while the second pressure regulating valve 10 that operates according to Formula 1 is used.
The with decreasing 2 in speed ratio pressure P _r 2 line pressure P _l2
To increase. Therefore, when the gear ratio P _r increases to a predetermined value and becomes equal to the second line oil pressure P _l2 , both of them are saturated and become constant thereafter. Figure 4 straight lines show the change characteristics of the P _mec (maximum value of the second line pressure P _l2) basic hydraulic pressure pressure is regulated according to equation 1 in relation to the speed ratio pressure P _r in the second pressure regulating valve 102 . The second pressure regulating valve 1
The basic hydraulic pressure P _mec obtained by the valve mechanism 02 is a value mechanically determined in relation to the pressure receiving area of the spool valve element 110 of the second pressure regulating valve 102 and the plunger 116, and is sufficiently larger than the ideal pressure P _opt. It is set high.

The first line oil pressure P _l1 adjusted by the first pressure adjusting valve 100 and the second line oil pressure P _l2 adjusted by the second pressure adjusting valve 102 are used to adjust the gear ratio γ of the CVT 14. It is supplied to one and the other of the primary side hydraulic cylinder 54 and the secondary side hydraulic cylinder 56 by a shift control valve device (not shown) composed of a shift direction switching valve and a flow rate control valve.

The linear valve 180 generates the output signal pressure P _solL by using the modulator pressure P _mo regulated to a constant value from the first line hydraulic pressure P _l1 by a pressure regulating valve (not shown) as a _source pressure. , Valve body 182
Spool valve element 186 slidably fitted in the cylinder bore 184 of the cylinder, a linear solenoid 188 excited by a drive voltage signal (control signal value) D supplied from the electronic control unit 260, and the linear solenoid 188.
A core 190 that urges the spool valve element 186 to the pressure increasing side based on an electromagnetic force generated in association with the excitation state of the coil, and a spring 192 that urges the spool valve element 186 to the pressure reducing side.
_And a feedback oil chamber 194 to which the output signal pressure P _solL is introduced in order to _{urge the} spool valve 186 to the pressure reducing side. The spool valve element 186 is operated so as to move to a position where the pressure-increasing urging force applied from the core 190 and the pressure-lowering urging force applied from the spring 192 are moved to a position where they are in equilibrium. The output signal pressure P _solL is changed based on the drive voltage signal D supplied from the electronic control unit 260 according to the output characteristic shown in FIG. The signal pressure P _solL output in this way is the linear valve 180
Is supplied to the chamber 136 of the second pressure regulating valve 102 from the output port 196 of the second pressure regulating valve 102, so that the target pressure P _opt lowered from the basic hydraulic pressure P _mec by a predetermined lowering pressure P _down is applied to the second pressure regulating valve 10.
It is output from 2.

The drive voltage signal D for the linear valve 180 is
To stabilize removed and the operation hysteresis of the linear valve 180, for example, its duty ratio D _UTY at a frequency of about 300Hz is a pulse signal which is varied for example from 0% to 100% linear solenoid 188 The driving current I _solL that actually flows in is a continuous current that changes in a sawtooth shape due to the influence of the inductance of the linear solenoid 188, and its average directly corresponds to the duty ratio D _uty of the driving voltage signal D. current value changes, directly corresponds to the duty ratio D _UTY of the drive voltage signal D.

Returning to FIG. 2, the electronic control unit 260 is
A first solenoid valve 262 and a second solenoid valve 264 for controlling the shift direction switching valve and the flow rate control valve, a third solenoid valve 266 for controlling a clutch control valve (not shown), and a fourth solenoid for controlling a relay valve. Valve 268, the linear valve 18
By selectively driving the 0, the gear ratio of the CVT 14 gamma, engagement of the lock-up clutch 36 of the fluid coupling 12, as well as controls the increase or decrease in the second line pressure P _l2, the tension of the transmission belt 44 Second control pressure
Performing optimum control of the line pressure P _l2.

The electronic control unit 260 includes a CPU, a RAM,
A so-called microcomputer including a ROM and the like is provided, which includes a vehicle speed sensor 272 that detects the rotational speed of the drive wheels 24, an input shaft 30 and an output shaft 38 of the CVT 14.
Input shaft rotation sensor 274 for detecting the rotation speed of each
And an output shaft rotation sensor 276, a throttle sensor 278 that detects the opening of a throttle valve provided in the intake pipe of the engine 10, an operation position sensor 282 that detects the operation position of the shift lever 280, and an operation of the brake pedal. from a brake switch 284, an engine speed sensor 286 for detecting the rotational speed N _e of the engine 10, the output pressure of the second pressure regulating valve 102, i.e. an oil pressure sensor 288 which detects the second line pressure P _l2 to the vehicle speed S
A signal representing PD, a signal representing input shaft rotation speed N _in , a signal representing output shaft rotation speed N _out , a signal representing throttle valve opening θ _th , a signal representing operation position P _s of shift lever 280, and a brake operation. A signal indicating the engine rotation speed, a signal indicating the engine rotation speed N _e, and a signal indicating the output pressure P _sns (basic oil pressure P _mec ) of the oil pressure sensor 288 are respectively supplied. The CPU in the electronic control unit 260 processes the input signal according to a program stored in advance in the ROM while utilizing the temporary storage function of the RAM, and the first solenoid valve 262 and the second solenoid valve 26 are processed.
4, third solenoid valve 266, fourth solenoid valve 268, linear valve 1
A signal for driving 80 is output.

[0027] Hereinafter, main control operation of the electronic control device 260, i.e., the second line pressure optimal control for the second line pressure P _l2 match the ideal pressure P _opt with reference to the flowchart of FIG. 8 in detail explain. In a step (not shown) in FIG. 8, input signals and the like from each sensor are read, and based on the read signals, the rotation speed N _in of the input shaft 30, the rotation speed N _out of the output shaft 38, and CVT1.
The gear ratio γ of 4, the vehicle speed SPD, etc. are calculated.

In step S1 of FIG. 8, the actual input torque T _in , the actual engagement diameter D _in of the transmission belt 44, and the output shaft rotation speed N are calculated from the relationship stored in the equation 3 in advance.
Based on _out , the optimum target pressure (ideal pressure) P _opt that can sufficiently transmit the input torque within the range where the transmission belt 44 does not slip is calculated. That is, this step S1 corresponds to the target pressure determining means of the present invention. The second term on the right side of Equation 3 is a centrifugal hydraulic pressure correction term, and the third term on the right side is a margin value. C ₁ and C ₂ are constants. Further, the input torque T _in, that is, the engine 1
The output torque T _{e of} 0 is calculated, for example, from a well-known formula based on the engine rotation speed N _e (= N _in ) and the throttle valve opening θ _th , or a parameter in which the intake pipe negative pressure PM is added, Hanging diameter of the transmission belt 44 D _in
Is calculated from the actual gear ratio γ of the CVT 14 (= rotational speed N _in of the input shaft 30 / rotational speed N _out of the output shaft 38).

[0029]

[Equation 3]

In the following step S2, the second pressure regulating valve 1
In 02, the mechanically determined basic oil pressure P _mec is calculated based on the actual throttle pressure P _th and the gear ratio specific pressure P _r from the pre-stored relationship shown in Expression 4. The relationship shown in Equation 4 is shown by the straight line in FIG. 4, and is stored as a data map, for example.

[0031]

[Equation 4]

In the following step S3, the above step S2
In Equation 5, the difference between the basic oil pressure P _mec calculated from Equation 4 and the target pressure P _opt calculated in step S1, that is, the reduced pressure P _down for obtaining the target pressure P _opt is Equation 5
Calculated from A, B, and C in FIG. 4 are the reduced pressure P _down.
Are shown respectively.

[0033]

[Equation 5]

Next, at step S4, the feedforward term (feedforward value PCTRB) included in each of the feedback control formula used in the feedback control of step S11 described later or the feedforward control formula used in the feedforward control of step S12 described later. ) Is calculated. The feedback control formula and the feedforward control formula are shown in, for example, Formulas 6 and 7, and the feedforward value PCTRB (hydraulic pressure conversion value) is
Shown in the first term on the right side of Equation 6 and the right side of Equation 7 (P
_down + P _HOSEI ). In the feedback control equation of Equation 6, ΔP is the control deviation (P _dact -P
_opt ), α is a coefficient for converting the hydraulic conversion value into the duty ratio D _uty , P _HOSEI is a learning correction value, k _p is a proportional constant, k _i is an integration constant, and k _d is a differential constant. Is. The learning correction value P _HOSEI included in the feedforward value PCTRB is, for example, as shown in FIG.
Throttle valve opening degree θ _th corresponding to the load amount of the engine 10
And a duty ratio D _uty of the drive voltage D of the linear valve 180 are stored as a two-dimensional map in the RAM in advance. _Stored value of this two-dimensional map SRAM _mn
Are updated by a learning routine executed in step S13 described later.

[0035]

[Equation 6]

[0036]

[Equation 7]

Next, in steps S5 to S10, it is determined whether the vehicle is in a stable state. That is,
First, in step S5, it is determined whether or not the CVT 14 is in the rapid shift mode, and in step S6, the second solenoid valve 2 is operated.
It is determined whether or not it is in the duty shift mode in which the gear ratio γ of the CVT 14 is changed at an intermediate speed by driving 64 of the duty ratio. In step S7, the clutch control valve for executing the engagement control of the lockup clutch 36 is determined. It is determined whether or not the duty driving operation of the third solenoid valve 266 for controlling the control is being performed. In step S8, it is determined whether or not the changing speed dθ _th / dt of the throttle valve opening θ _th is larger than a predetermined value ε. is, in step S9, whether working oil temperature T _oil is lower than a predetermined value T _O is determined, in step S10, whether or not learning control abnormality is judged.

In step S5, the gear ratio γ of the CVT 14 is set.
Is for determining the gear ratio transients are rapidly changing, the steps S6, S7 is for determining a period during which there is a risk that the pulsation in the second line pressure P _l2 is generated by the duty control Yes, the step S8 is for judging a throttle valve opening transient state in which the throttle valve opening θ _th changes abruptly, and the step S9 has a low hydraulic oil temperature T _oil of the hydraulic control circuit and a viscous viscosity. This is for judging the state in which the normal pressure adjusting operation of the second pressure adjusting valve 102 or the like is not expected to be high. Further, step S10 is for determining an abnormality of the hydraulic pressure sensor 288.

[0039] If any of the determination in step S5 to S10 is is affirmative, since the transient state of the second line pressure P _l2, although feedforward control in step S12 is executed according to Equation 7 If all the determinations in steps S5 to S10 are negative, the second line pressure P 12 _{is in} a stable state, and thus the feedback control in step S11 is executed according to the equation (6). In the feedforward control of step S12, the feedforward value PCTRB (hydraulic pressure conversion value) obtained in step S4 is multiplied by α so that the duty ratio D _uty of the drive voltage D, which is the operation amount of the feedforward control, is _calculated. Is calculated.

FIG. 10 is a flow chart for explaining the feedback control in detail. In the figure, in step S111, the detected pressure detected P _dact by the hydraulic pressure sensor 288, i.e. with the second line pressure P _l2 actual is read, in step S112, the control deviation Δ
P (= P _dact −P _opt ) is calculated. Next, in step S113, the feedback control value PFB is calculated. This feedback control value PFB (hydraulic pressure conversion value)
Is the sum of the proportional term value T _PPD , the integral term value T _IPD , and the derivative term value T _DPD shown in parentheses in the second term on the right side of the equation 6. The values T _PPD , T _IPD , and T _DPD are shown in Expressions 8, 9, and 10.

[0041]

[Equation 8]

[0042]

[Equation 9]

[0043]

[Equation 10]

Then, in step S114, the feedforward value PC obtained in step S4 is calculated.
After the TRB and the feedback control value PFB obtained in step S113 are added and multiplied by the coefficient α, the duty ratio D _uty of the drive voltage D, which is the operation amount of the feedback control, is calculated. It is output in the following step S115.

Next, at step S13, a learning routine for updating the learning correction value P _HOSEI is executed according to the flowchart shown in FIG. In the figure, first, whether the feedback control of the second line pressure P _l2 is in a stable state is determined in step S131 to S133 to determine whether preconditions learning are in place. That is, in step S131, it is determined whether or not the feedback control in step S11 is being executed, and in step S132, the control deviation Δ
The absolute value of P (= P _dact -P _opt ) is a preset value E
It is determined whether or not it is smaller, and in step S133,
It is determined whether the affirmative determination in step S132 lasts for a preset time h seconds or longer. The judgment reference value E and the judgment reference time h seconds indicate the deviation value range and the duration for judging that the feedback control is in a stable state. For example, the judgment reference value E is 3 to 7 kg / cm ² A value of about 1 to 3 seconds is adopted as the value of the degree and the judgment reference time h.

If any of the judgments in steps S131 to S133 is denied, this learning routine is ended. However, those steps S131 to S
If all determinations at 133 are affirmative, step S
At 134, the learning term reference routine shown in FIG. 12 is executed. In step S1341 in FIG. 12, when the duty ratio D _UTY the actual throttle valve opening theta _th and the driving voltage signal D at that time is read simultaneously, the lattice points on the basis of their throttle opening theta _th and the duty ratio D _UTY (M ', n') is calculated. Then, step S
In 1342, the stored value SRAM _{m'n '} corresponding to the grid point (m', n ') is read from the two-dimensional map shown in FIG. 9 stored in advance in the RAM.

Returning to FIG. 11, in step S135,
The value of the integral term T _{IPD of the} feedback control equation shown in Equation 6
Is greater than or equal to a preset lower limit value −L, and if the determination in step S135 is affirmative, the value T _{IPD of the} integral term in step S136 is a preset upper limit value + L. It is determined whether or not the above. If the determination in step S135 is negative, the stored value SRA up to that point is determined in step S137.
Subtract "1" from M _{m'n '} . Also, the above step S1
If the determination in 36 is denied, the stored value SRAM _{m'n 'up} to that _point is held in step S138. If the determination in step S136 is affirmative, the stored value SRA up to that point is determined in step S139.
"1" is added to M _{m'n '} . That is, when the value T _IPD of the integral term in the stable control state is within the range from the lower limit value −L to the upper limit value L, the stored value SRAM _{m′n ′} is held at the value up to that point, but the lower limit value − When it goes below L, the stored value SRAM _{m'n '}
Is updated to a smaller value until then, and when the upper limit value L is _exceeded , the stored value SRAM _{m'n '} is updated to a larger value until then.

By the above learning correction, when the stored value SRAM _{m'n '} is updated or held on the basis of the value T _IPD of the integral term in the stable control state, whether or not the value is an abnormal value continues. It is determined in step S1310. This abnormal value indicates that the value cannot be various variations in a normal state due to a failure of the linear valve 180 that cannot be electrically detected, and is, for example, a predetermined upper limit value and a lower limit value. Judgment is made by exceeding the normal range indicated by. Then, in step S1311, if the above value is not an abnormal value, it is stored as it is in the two-dimensional map, but if it is an abnormal value, its initial value is stored and this routine is terminated.

As a result of repeating the above steps, the stored value SRA is generated once every h seconds in the process of continuing the closed loop control by the control formula shown in Formula 6.
M _{m'n '} is updated one by one and its stored value SRA
As a result of changing the learning correction value P _HOSEI by updating M _{m'n '} , the value T _{IPD of the} integral term is changed in the direction of decreasing. Then, the learning is continued until the value T _{IPD of the} integral term is within a predetermined range (+ L to −L). The predetermined range (+ L to −L) is determined so as to be within the range when the value T _{IPD of the} integral term becomes a value of “0” or a value close thereto.

FIG. 13 is a control block diagram of an apparatus having the same function as this embodiment. In the figure, the engine output torque T _e calculated in the same manner as above is calculated by the engine output torque calculation means 290, and the transmission belt 44
Theoretical clamping force calculation means 2 for generating the theoretical clamping force of
92, the hydraulic pressure value C ₁ · T _in / D _in, and the centrifugal hydraulic pressure calculation unit 294 calculates the centrifugal hydraulic pressure value C ₂ ·
The target pressure P _opt is calculated by the target pressure calculation means 296 from N _out ² . Feedback value calculation means 302
Is a feedback value PF for eliminating the control deviation ΔP
Calculate B. The learning means 300 determines the learning correction value P _HOSEI based on the value of the integral term of the feedback control equation in the stable control state from the feedback value calculation means 302, and in addition to the pressure drop value P _down , the feedforward value calculation means 304. Supply to. The feedforward value calculation means 304 has a basic oil pressure P _mec calculated by the basic oil pressure calculation means 298, a target pressure P _opt, and a learning correction value P.
The feedforward value PCTRB for achieving the target pressure P _opt is calculated from _HOSEI . Pressure regulation control means 306
Is the feedback value PFB from the feedback value calculation means 302 and the feedforward value calculation means 30.
The feedback control value D _uty is calculated from the equation 6 based on the feedforward value PCTRB from the equation 4 and the feedforward control value D is calculated from the equation 7.
_{The uty} is calculated, and if the second line oil pressure P 12 _{is in} a stable state, the linear valve 180 is driven with the feedback control value D _uty, but if the second line oil pressure P 12 _{is in} a transient state, the feedforward control value is obtained. Linear valve 180 at _Duty
To drive. The pressure adjusting control means 306 functions as a feedback control means, a feedforward control means, and a switching means.

[0051] As described above, according to this embodiment, step S11 through steps S5 to S10 correspond to the switching means, corresponding to the feedback control means in a stable state of the second line pressure P _l2 is the torque capacity control pressure the execution selection, since the transient state of the second line pressure P _l2 execution of step S12, corresponding to the feed-forward control means is selected, the shift is performed or if CVT14 the accelerator operation amount of the vehicle was varied If it is, or the shift control valve, the disturbance greater when transient state of the second line pressure P _l2, such as, such as when the lockup clutch control valve is duty-driven, torque capacity control by the feed forward control The pressure is controlled stably.

Also, step S13 corresponding to the learning means.
, The second line pressure P _l2 of learning correction value based on the value of the integral term of the feedback controlling expression of Equation 6 in the stable state feedforward controlled in Equation 7 P
_{Since HOSEI} is modified, in the event of failure of the transient or oil pressure sensor 288, it is increased a second line pressure P _l2 control accuracy by the feed forward control, a value close to the target pressure can be suitably obtained. That is, the control based on the feedforward control formula of Formula 7 is optimized.

Further, according to the present embodiment, the learning correction value P _HOSEI included in the feedforward term in the feedback control equation of Expression 6 is also learned and corrected, so the calculated value of the basic oil pressure P _mec and the linear valve 180. drive current and the output characteristics, the throttle pressure P _th, variations such as the actual pressure value of the second pressure regulating valve 102 is absorbed, the second line pressure P _l2 control by feedback control is also optimized. Therefore, the margin pressure given to the target pressure P _opt can be made as small as possible, and the power loss is suitably reduced. According to an experiment by the present inventor, it was possible to lower the target pressure P _opt by about 3 kg / cm ² as compared with the conventional target pressure P _opt .

Incidentally, FIG. 14 shows the control characteristics according to the above-mentioned embodiment in comparison with the conventional control characteristics. In the figure, the target pressure P is related to the return operation of the accelerator pedal.
_opt has changed in the second line pressure P _l2 is illustrated in the case of reduced stepwise, to change due to the feedback control based on the control deviation ΔP is dashed (a), the change by the feed forward control is the solid line (b) and One-dot chain line (c)
In addition, the changes due to the control equation in which the feedback term is added to the feedforward term of the solid line (b) and the one-dot chain line (c) are shown in the two-dot chain line (d) and the three-dot chain line (e), respectively. .. As shown in the figure, the change due to the mere feedback control shown by the broken line (a) gives the target pressure P _opt but no responsiveness, and the settling time t ₃ is long. On the other hand, the change due to the feedforward control shown by the solid line (b) and the one-dot chain line (c) has better responsiveness, but variation occurs and accuracy with respect to the target pressure P _opt cannot be obtained. This variation is due to variations in the calculated value of the basic oil pressure P _mec , variations in the drive current of the linear valve 180, variations in the pressure adjustment value of the linear valve 180, variations in the pressure adjustment value of the second pressure adjustment valve 102, and the like. is there.

As an improvement on the above, the two-dot chain line (d) and 3
Control by a control equation having a feedforward term and a feedback term shown by the dashed line (e) can be considered. According to this, the target pressure P _opt is surely obtained, but it is inevitable that the settling time varies as shown by t ₁ and t ₂ . On the other hand, according to the present embodiment,
Based on the value of the integral term of the feedback control equation of Eq. 7, the learning correction value P _HOSEI of the feedforward control equation of Eq.
Is corrected, so that the responsiveness and the control accuracy can be obtained at the same time without variation, as shown by the chain double-dashed line (d) in FIG.

Next, another embodiment of the present invention will be described. In the following embodiments, the same parts as those in the above-mentioned embodiments are designated by the same reference numerals and the description thereof will be omitted.

Steps S1312 and S shown in FIG.
1313 may be provided in a part of the flowchart shown in FIG. 8 or FIG. 11, for example, before or after step S1311. In this step S1312, failure determination is executed. This failure determination includes three types of determination,
First, as shown in (a) of FIG. 16, for example, part or all of the stored value SRAM _mn (learning correction value) of the two-dimensional map shown in FIG. 9 reaches the preset upper limit value UG. Determine whether or not Secondly, for example, in FIG.
As shown in (b) of 6, the stored value SR of the two-dimensional map
It is determined whether a part or all of AM _mn (learning correction value) has reached a preset lower limit value LG. Thirdly, as shown in (c) of FIG. 16, whether or not the stored value SRAM _mn (learning correction value) of the two-dimensional map exists at the preset upper limit value UG and lower limit value LG. To judge. If any of the first to third judgments is affirmative, a failure display is made in step S1313, or a diagnosis failure code indicating the failure is stored in preparation for diagnosis.

For example, when the first judgment is affirmative, it is judged that the linear valve 180 is in the ON state and the ON failure is maintained. When the second judgment is affirmative, the linear valve 180 is judged to be linear. When it is determined that the valve 180 is kept in the OFF state and the OFF failure occurs and the third determination is positive, the valve stick failure in which the linear valve 180 and the spool valve element 110 of the second pressure regulating valve 102 are stuck. Is determined.
The upper limit value UG and the lower limit value LG are set to values slightly smaller than the abnormality determination reference value in step S1310.

Although one embodiment of the present invention has been described above with reference to the drawings, the present invention can be applied to other modes.

For example, the above-described embodiment is an example in which the CVT 14 is used as a vehicle power transmission device. However, a plurality of sets of planetary gear device elements are selectively connected by a friction engagement device to provide a plurality of elements. It is also possible to use an automatic transmission of the type that establishes the gears, a continuously variable transmission of the traction type, an automatic clutch, or the like.

In the above embodiment, the learning correction value P
_As shown in the two-dimensional map shown in FIG. 9 for reading out _HOSEI , the throttle valve opening θ _th and the duty ratio D
The value stored value SRAM _mn corresponds to the _uty are prepared respectively, a throttle valve opening theta _th and the vehicle speed of the two-dimensional map, the throttle valve opening theta _th and the gear ratio two-dimensional map of gamma,
Throttle opening theta _th, the duty ratio D _UTY, such as a three-dimensional map of the vehicle speed, throttle opening theta _th, the duty ratio D _UTY, vehicle speed SPD, the at least one stored value SRAM in response to parameters of the speed ratio γ is It may be prepared.

Further, although the feedback control equation shown in Equation 6 of the above-mentioned embodiment includes the feedforward term, even if it does not include the feedforward term, the temporary effect of the present invention can be obtained.

Further, in the above-described embodiment, the second pressure regulating valve 10
By 2 to the throttle pressure P _th and the speed ratio pressure P _r is allowed to act, but the basic oil pressure P _mec shown in the straight line in FIG. 4 was configured so as to obtain the speed ratio pressure P _r is not allowed to act It does not matter even if it is a type of pressure regulating valve. The basic oil pressure P _{mec in} this case is represented by a plurality of straight lines parallel to the horizontal axis of FIG. 4 with the throttle pressure P _th as a parameter.

In addition, the above-mentioned feedforward value PCT
The RB (hydraulic pressure conversion value) is (P _down + P _HOSEI ) as shown in the first term on the right side of Expression 6 and the right side of Expression 7, but a predetermined margin value may be added to it. ,
The size of the α coefficient for converting the duty ratio D _UTY hydraulic converted value may be set greater by a predetermined margin ratio.

Further, although the learning routine of step S13 in the above-mentioned embodiment is executed after step S11 or S12, it is not limited to that position.

Further, in the above embodiment, the linear valve 180
Although the drive voltage D for driving the pulse voltage is a pulse voltage having a predetermined duty ratio D _uty , it may be a DC voltage that does not include an AC component. In this case, the control operation amount calculated by Expressions 6 and 7 for driving the linear valve 180 is the drive voltage or the drive current.

Further, in the power transmission system of the above-mentioned embodiment, the auxiliary transmission having a plurality of forward gear stages may be provided at the front stage or the rear stage of the CVT 14. When shifting the gear stage of the auxiliary transmission, the shift solenoid valve may be duty-driven in order to absorb the shift shock. However, by providing the same step as step S6 or S7 in FIG. The feedforward control is controlled so as to be selected during a period in which the solenoid valve for duty is driven.

The above description is merely one embodiment of the present invention, and the present invention can be variously modified without departing from the gist thereof.

[Brief description of drawings]

FIG. 1 is a diagram showing a main configuration of the present invention.

FIG. 2 is a skeleton view showing a power transmission device for a vehicle provided with a hydraulic control device according to an embodiment of the present invention.

FIG. 3 is a diagram showing in detail a main part of the hydraulic control circuit of FIG.

FIG. 4 is a diagram showing pressure regulating characteristics of a second pressure regulating valve of FIG.

5 is a diagram showing a change characteristic of the throttle pressure of FIG.

FIG. 6 is a diagram showing a change characteristic of the gear ratio specific pressure of FIG.

FIG. 7 is a diagram showing output characteristics of the linear valve of FIG.

8 is a flowchart illustrating a main part of the operation of the electronic control device of FIG.

9 is a diagram illustrating the relationship used in the flowchart of FIG. 8 and illustrating the configuration of a two-dimensional map stored in advance in the ROM of the electronic control device of FIG.

10 is a flowchart illustrating the operation of the feedback control routine of step S11 of FIG.

FIG. 11 is a flowchart illustrating an operation of a learning routine of step S13 of FIG.

FIG. 12 is a flowchart illustrating an operation of a learning term reference routine in step S134 of FIG.

FIG. 13 is a control block diagram illustrating a main part of the operation of the electronic control device of FIG.

[14] The control characteristic of the second line pressure P _l2 obtained as a result of the operation shown in FIG. 8 is a time chart for explaining in comparison with the conventional case.

FIG. 15 is a flow chart illustrating an essential part of the operation of another embodiment of the present invention.

16 is a diagram for explaining in detail the failure determination content of FIG.

[Explanation of symbols]

14 CVT (vehicle power transmission device) 102 second pressure regulating valve, 180 linear valve (pressure regulating means) 260 electronic control device (control means) 306 pressure regulating control means (feedback control means, feedforward control means, switching means) Step S1 Target pressure determining means Steps S5 to S10 Switching means Step S11 Feedback control means Step S12 Feedforward control means Step S13 Learning means

Claims (1)

[Claims] 1. A target pressure determining means for determining a target pressure of a torque capacity control pressure related to a transmission torque capacity of a vehicle power transmission device based on a vehicle state, and a torque pressure control pressure based on a control signal. A hydraulic control device for a power transmission device for a vehicle, comprising: a pressure adjusting means for applying pressure; and a control means for outputting the control signal so that a deviation between the actual torque capacity control pressure and the target pressure is eliminated. Feedback control means for generating the control signal based on a feedback control equation including an integral term for calculating a control amount corresponding to the integral value of the deviation, and a feedforward value for obtaining the target pressure. Feedforward control means for generating the control signal based on a feedforward control equation including a learning correction value for correcting the feedforward value, Switching means for selecting the feedback control means in the stable state of the torque capacity control pressure and selecting the feedforward control means in the transient state of the torque capacity control pressure; and the feedback control in the stable state of the torque capacity control pressure. And a learning unit that corrects the learning correction value of the feedforward control formula based on the value of the integral term of the formula.