JP2014013088A - Vehicle control apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle control apparatus capable of improving controllability of slip start control by accurately finding a relationship between a lock-up differential pressure indication value and a lock-up differential pressure due to the lock-up differential pressure indication value.SOLUTION: A hydraulic learning is executed at the time of lock-up control when a speed ratio after a vehicle is started (a ratio of a turbine speed to an engine speed) reaches a predetermined value or more. Execution of slip start control is prohibited until the hydraulic learning is executed predetermined times. When a slip start control execution permission condition is established after the hydraulic learning is executed the predetermined times, the slit start control is executed at the next time the vehicle is started.

Description

  The present invention relates to a vehicle control device equipped with a fluid power transmission device such as a torque converter having a lock-up clutch. In particular, the present invention relates to an improvement in start control in a vehicle capable of executing slip start control (also referred to as flex start control) in which a lockup clutch is in a semi-engaged state as the vehicle starts.

  Conventionally, in a vehicle equipped with an engine, the transmission ratio between the engine and the drive wheel is automatically set as a transmission that appropriately transmits the torque and rotation speed generated by the engine to the drive wheel according to the traveling state of the vehicle. An automatic transmission that is optimally set for the motor is known.

  As an automatic transmission mounted on a vehicle, for example, a planetary gear type transmission that sets a gear ratio (gear stage) using a clutch and brake and a planetary gear device, or a belt type that adjusts the gear ratio steplessly There is a continuously variable transmission (CVT).

  Further, in a vehicle equipped with this type of automatic transmission, a fluid power transmission device such as a fluid coupling or a torque converter is disposed between the engine and the automatic transmission. Further, a fluid power transmission device having a lock-up clutch is known (see, for example, Patent Document 1 and Patent Document 2 below). This lock-up clutch enables frictional engagement with hydraulic pressure of hydraulic oil (hereinafter sometimes referred to as oil), thereby enabling direct connection between the input side and the output side of the fluid power transmission device.

  In a vehicle equipped with such a fluid power transmission device with a lock-up clutch, for example, the lock-up clutch is operated using the hydraulic pressure (line pressure) of a hydraulic control system including the hydraulic control of the automatic transmission as a source pressure. By controlling the hydraulic pressure acting on the lockup clutch, the engagement state, half-engagement state (flex lockup state), and release state of the lockup clutch are controlled.

  Specifically, in the case of a torque converter with a lock-up clutch, a solenoid valve for lock-up differential pressure control, a lock-up control valve, etc. are used to connect the torque converter between the engagement-side oil chamber and the release-side oil chamber. Control of engagement / half-engagement / release of the lock-up clutch is performed by controlling the differential pressure (lock-up differential pressure) based on the lock-up differential pressure instruction value (for example, duty control of the solenoid valve). .

  Further, as disclosed in Patent Document 3 and Patent Document 4 below, a slip that causes the lockup clutch to be in a semi-engaged state when the vehicle on which the fluid power transmission device with the lockup clutch is mounted is started. One that performs start control is also known. By executing this slip start control, power transmission loss in the torque converter at the start of the vehicle is reduced, and a sudden increase in engine speed (so-called swell) is suppressed, thereby improving the fuel consumption rate. It becomes possible to plan.

JP 2009-85319 A JP 2007-205509 A JP 2006-250287 A JP 2005-16563 A

  In the fluid power transmission device with a lock-up clutch that performs the slip start control described above, the torque capacity of the lock-up clutch when starting the vehicle (the magnitude of torque transmitted by the engagement of the lock-up clutch) Control needs to be performed with high accuracy. This is because when the torque capacity of the lock-up clutch is larger than the appropriate torque capacity (for example, when the torque capacity becomes larger at an earlier timing than the appropriate timing), the engine speed rapidly decreases. This is because there is a possibility that an engine stall may occur. Conversely, when the torque capacity of the lock-up clutch is smaller than the appropriate torque capacity (for example, when the torque capacity increases at a timing later than the appropriate timing), until the torque capacity is obtained. This is also because the engine speed rapidly increases, the fuel consumption rate deteriorates, and the purpose of the slip start control may not be achieved.

  However, due to individual differences at the time of manufacture of the above-mentioned lock-up differential pressure control solenoid valve and characteristic changes accompanying long-term use, etc., the torque capacity generation characteristics of the lock-up clutch (timing at which torque capacity is generated, etc.) Will result in variations.

  FIG. 10 shows the accelerator opening, the engine speed, the turbine speed, the lockup differential pressure instruction, and the lockup actual differential pressure in this case (when the lockup actual differential pressure deviates from an appropriate value due to the above-described variation). It is a timing chart figure showing an example of change of. The waveforms of the engine speed and the lockup actual differential pressure indicated by the solid line in FIG. 10 are obtained when the torque capacity of the lockup clutch becomes larger at an earlier timing than the appropriate timing (the above variation is the lockup actual differential pressure). The upper limit product that deviates to the side of increasing The waveform of the engine speed and the actual lockup differential pressure indicated by the broken line increases when the torque capacity of the lockup clutch increases at a timing later than the appropriate timing (the above-mentioned variation tends to decrease the actual lockup differential pressure). The lower limit product). Note that the waveform of the actual lockup differential pressure indicated by the two-dot chain line indicates a case where an appropriate actual lockup differential pressure is obtained (nominal product). In this way, when the lockup actual differential pressure deviates to the side (upper limit product), the torque capacity of the lockup clutch becomes larger than the appropriate torque capacity, and the engine speed decreases rapidly. (See engine speed indicated by solid line). In addition, if the actual lockup differential pressure deviates (lower limit product), the torque capacity of the lockup clutch becomes smaller than the appropriate torque capacity and the engine speed increases rapidly (as indicated by the broken line). See engine speed shown).

  For this reason, a learning operation is required to appropriately obtain the lockup differential pressure when the slip start control is executed. This learning operation is performed when the lockup differential pressure is generated, that is, after the slip start control is started (after the lockup differential pressure instruction is output), the lockup differential pressure is actually generated and the lockup clutch is This is performed in order to optimize the timing of engagement (timing at which torque capacity is generated).

  Specifically, at the start of the slip start control, calculation of the torque capacity of the lockup clutch according to the following equation (1) is repeated at predetermined time intervals, and a change in the torque capacity of the lockup clutch, for example, the torque capacity is “0”. From this state, it is determined whether or not the time when the torque capacity becomes “positive value” (the timing at which torque transmission by the engagement of the lockup clutch is started) is obtained at an appropriate timing. When the torque capacity change timing is later than the appropriate change timing, learning correction is performed to increase the differential pressure instruction value to the lockup clutch, while the torque capacity change timing is the appropriate change timing. If it is earlier, learning correction is performed so as to lower the differential pressure instruction value to the lockup clutch.

  A lockup differential pressure map that prescribes the relationship between the differential pressure command value of the lockup clutch and the lockup differential pressure is created in advance so that the change timing of the lockup differential pressure approaches the appropriate change timing. In some cases, the lock-up differential pressure map is corrected by learning.

TCL = Te−C · Ne ² −Ie · ΔNe (1)
TCL is the torque capacity of the lockup clutch, Te is the torque of the engine, C is the capacity coefficient of the torque converter, Ne is the engine speed, Ie is the inertia of the engine, and ΔNe is the amount of change per unit time of the engine speed. is there.

  However, in the learning operation performed at the start of the slip start control as described above, as described below, sufficient learning accuracy is not obtained, and in order to properly obtain the torque capacity of the lockup clutch. Further improvements were required.

  That is, when the vehicle starts, it is a transitional time in which the amount of depression of the driver's accelerator pedal changes greatly, so that it is difficult to sufficiently obtain the accuracy of each term in the above equation (1). For example, during this transition, the amount of change per unit time of the engine torque (the first term on the right side of Equation (1): Te) is large, so that it is difficult to obtain sufficient estimation accuracy of the engine torque Te. Also, during this transition, the amount of change in the engine speed (Ne) per unit time is large, so the torque capacity of the torque converter (second term on the right side of Equation (1)) and inertia torque (on the right side of Equation (1)) It is difficult to sufficiently obtain the calculation accuracy of item (3). For this reason, it is difficult to accurately obtain the torque capacity TCL of the lockup clutch in the learning operation performed by the above equation (1) at the start of the slip start control. In particular, in an operation region where the ratio of the turbine speed to the engine speed at the initial stage of vehicle start-up (hereinafter referred to as “speed ratio”: Nt / Ne) is small, the engine is locked under the influence of centrifugal hydraulic pressure generated inside the torque converter. The up clutch operates to the engagement side, and torque capacity due to the centrifugal hydraulic pressure is generated in the lock up clutch. In this case, the cause of the torque capacity is that caused by the lockup differential pressure instruction and that caused by the centrifugal oil pressure, and the original hydraulic control (based on the lockup differential pressure instruction). It becomes impossible to accurately determine the magnitude of the torque capacity of the lock-up clutch generated by the control, which adversely affects the reliability of the learning accuracy.

  The present invention has been made in view of the above points, and the object of the present invention is to accurately determine the relationship between the lockup differential pressure instruction value and the lockup differential pressure resulting therefrom, and to perform slip start control. An object of the present invention is to provide a vehicle control device capable of improving controllability.

-Principle of solving the problem-
The solution principle of the present invention taken to achieve the above object prohibits hydraulic pressure learning at a timing when the fluctuation amount of the engine torque and the engine speed when the vehicle starts is large, and is executed at other timings. The slip start control is permitted to be executed in a state where the lockup differential pressure is corrected by the learned value in the hydraulic pressure learning.

-Solution-
Specifically, the present invention is premised on a vehicle control device capable of slip start control when starting a vehicle and lockup control during steady vehicle travel. The vehicle control apparatus is configured to permit the execution of slip start control after completion of the hydraulic pressure learning during the lockup control.

  Another solution is a slip start control in which a fluid power transmission device with a lock-up clutch is provided between the driving power source and the automatic transmission, and the lock-up clutch is half-engaged when starting. It is premised on a vehicle control device that is capable of the above. A hydraulic pressure learning means for performing lockup clutch hydraulic pressure learning at the time of lockup control during traveling of the vehicle after a predetermined period has elapsed from the start of the vehicle, and a lock executed by the hydraulic pressure learning means. The slip start control is prohibited until the up clutch hydraulic pressure learning is completed and the slip start control execution permission condition is satisfied, and the slip start control execution is permitted when the slip start control execution permission condition is satisfied. Start control permission means is provided.

  Due to this specific matter, the lockup clutch hydraulic pressure learning is performed at a timing other than when the vehicle starts (transition time) when the engine torque and the engine speed greatly fluctuate, thereby obtaining a highly reliable learning value. become. Since the slip start control is executed by the hydraulic pressure instruction value (for example, the lockup differential pressure instruction value) that has been learned and corrected with a highly reliable learning value in this way, the timing at which the lockup differential pressure is generated is an appropriate timing. Will be set to. As a result, when the vehicle starts, a sudden decrease in the engine speed due to the occurrence of the lockup differential pressure being too early and a sudden increase in the engine speed due to the occurrence of the lockup differential pressure being too late are avoided. Stall prevention and fuel consumption rate can be improved.

  Completion of the hydraulic pressure learning during the lockup control is established when the hydraulic pressure learning operation is performed a predetermined number of times. The slip start control execution permission condition is satisfied when the lockup clutch hydraulic pressure learning is performed a predetermined number of times.

  As a result, the slip start control can be permitted in a state where the learned hydraulic pressure instruction value (for example, the lockup differential pressure instruction value) has converged to an appropriate value, so that the operational effects of the above-described solving means can be exhibited more remarkably. be able to.

  In addition, when learning the oil pressure of the lockup clutch, the ratio of the input shaft speed to the output shaft speed of the lockup clutch is the torque capacity of the lockup clutch due to the centrifugal oil pressure generated inside the fluid type power transmission device. It is executed when it reaches a predetermined value that does not occur.

  According to this, the learning value is acquired in a situation where torque capacity due to the influence of the centrifugal hydraulic pressure generated inside the fluid type power transmission device (torque converter) is not generated, and the reliability of the learning value can be further enhanced. .

  In addition, the slip start control is prohibited from being executed every time the travel distance of the vehicle reaches a predetermined distance, and then the slip start control is allowed to be executed again after completion of the hydraulic pressure learning during the lockup control. Further, as a specific configuration of the slip start control permission means, the slip start control execution permission condition is not satisfied every time the travel distance of the vehicle reaches a predetermined distance, and then the lockup clutch hydraulic pressure learning executed by the hydraulic pressure learning means is performed. Is completed and slip start control execution permission conditions are satisfied again, the slip start control execution is permitted.

  As a result, slip start control is executed in a state in which an appropriate lockup differential pressure cannot be obtained due to a characteristic change of the fluid type power transmission device (for example, a characteristic change of a solenoid valve constituting the hydraulic circuit). Such a situation can be avoided.

In addition, the hydraulic pressure learning is performed by calculating the torque capacity of the lockup clutch,
TCL = Te−C · Ne ² −Ie · ΔNe (1)
TCL is the torque capacity of the lockup clutch, Te is the engine torque, C is the capacity coefficient of the torque converter, Ne is the engine speed, Ie is the engine inertia, ΔNe is the amount of change in the engine speed per unit time,
By calculating the torque capacity of the lockup clutch by the above, the generation timing of the torque capacity of the lockup clutch is learned.

  In the present invention, oil pressure learning is prohibited at a timing when the fluctuation amount of the engine torque and the engine speed at the time of start of the vehicle is large, and the lockup differential pressure is corrected by a learning value in oil pressure learning executed at other timings. In this state, the execution of slip start control is permitted. For this reason, when the vehicle starts, a sudden decrease in the engine speed due to the occurrence of the lockup differential pressure being too early and a sudden increase in the engine speed due to the occurrence of the lockup differential pressure being too late are avoided. Stall prevention and fuel consumption rate can be improved.

It is a figure showing a schematic structure of a powertrain of a vehicle concerning an embodiment. It is a figure which shows the hydraulic circuit which concerns on engagement / release control of a lockup clutch. It is a block diagram which shows the structure of control systems, such as ECU. It is a figure which shows an example of the shift map used for the shift control of a belt-type continuously variable transmission. It is a figure which shows an example of a lockup switching map. It is a figure which shows the relationship between lockup differential pressure instruction | indication value and lockup differential pressure. It is a flowchart for demonstrating execution permission operation | movement of slip start control. Accelerator opening, engine speed, turbine speed, lockup clutch torque capacity, lockup differential pressure indication, lockup differential pressure instruction, lockup actual differential pressure for explaining the operation to calculate the deviation between target dead time and actual dead time It is a timing chart figure which shows an example of a change. FIG. 7 is a timing chart showing an example of changes in the accelerator opening, engine speed, turbine speed, lockup clutch torque capacity, lockup differential pressure instruction, and lockup actual differential pressure after completion of the learning operation. FIG. 6 is a timing chart showing an example of changes in accelerator opening, engine speed, turbine speed, lock-up differential pressure instruction, and lock-up actual differential pressure when the lock-up actual differential pressure deviates from an appropriate value. .

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. This embodiment demonstrates the case where the vehicle control apparatus which concerns on this invention is applied to the vehicle carrying a belt-type continuously variable transmission (CVT) as a transmission.

  FIG. 1 is a diagram showing a schematic configuration of a vehicle power train in the present embodiment.

  The vehicle according to the present embodiment is an FF (front engine / front drive) type vehicle, which is an engine (internal combustion engine) 1 that is a driving power source, a torque converter 2 as a fluid power transmission device, and a forward / reverse switching device. 3, a belt-type continuously variable transmission 4, a reduction gear device 5, a differential gear device 6, an ECU (Electronic Control Unit) 8 (see FIG. 3), and the like are mounted, and the ECU 8 and lock-up control described later. A control device for the lockup clutch 24 is configured by the circuit 200 (a part of the hydraulic control circuit 20) and the like.

  A crankshaft 11, which is an output shaft of the engine 1, is connected to the torque converter 2, and the output of the engine 1 is transmitted from the torque converter 2 through the forward / reverse switching device 3, the belt type continuously variable transmission 4, and the reduction gear device 5. Are transmitted to the differential gear device 6 and distributed to the left and right drive wheels 7L, 7R.

  The parts of the engine 1, the torque converter 2, the forward / reverse switching device 3, the belt-type continuously variable transmission 4, and the ECU 8 will be described below.

-Engine-
The engine 1 is a multi-cylinder gasoline engine, for example. The intake air amount sucked into the engine 1 is adjusted by an electronically controlled throttle valve 12. The throttle valve 12 can electronically control the throttle opening independently of the driver's accelerator pedal operation, and the opening (throttle opening) is detected by the throttle opening sensor 102. . Further, the coolant temperature of the engine 1 is detected by a water temperature sensor 103.

  The throttle opening of the throttle valve 12 is driven and controlled by the ECU 8 (see FIG. 3). Specifically, the optimum intake air amount (in accordance with the operating state of the engine 1 such as the engine speed Ne detected by the engine speed sensor 101 and the accelerator pedal depression amount (accelerator operation amount Acc) of the driver). The throttle opening of the throttle valve 12 is controlled so as to obtain a target intake air amount. More specifically, the actual throttle opening of the throttle valve 12 is detected using the throttle opening sensor 102, and the actual throttle opening becomes the throttle opening (target throttle opening) at which the target intake air amount is obtained. The throttle motor 13 of the throttle valve 12 is feedback controlled so as to match.

-Torque converter-
The torque converter 2 includes an input-side pump impeller 21, an output-side turbine runner 22, a stator 23 that exhibits a torque amplifying function, and the like. Transmit power. The pump impeller 21 is connected to the crankshaft 11 of the engine 1. The turbine runner 22 is connected to the forward / reverse switching device 3 via the turbine shaft 28.

  The torque converter 2 is provided with a lockup clutch (lockup clutch mechanism) 24 that directly connects the input side and the output side of the torque converter 2. The lock-up clutch 24 is configured such that a differential pressure between the hydraulic pressure in the engagement-side oil chamber 25 and the hydraulic pressure in the release-side oil chamber 26 (lock-up differential pressure = hydraulic pressure Pon in the engagement-side oil chamber 25−release-side oil chamber). By controlling the hydraulic pressure Poff) in 26, full engagement, half engagement (engagement in the slip state) or release is achieved.

  By completely engaging the lockup clutch 24, the pump impeller 21 and the turbine runner 22 rotate integrally. Further, by engaging the lockup clutch 24 in a predetermined slip state (half-engaged state), the turbine runner 22 rotates following the pump impeller 21 with a predetermined slip amount when the engine driving force is transmitted. On the other hand, the lockup clutch 24 is released by setting the lockup differential pressure to be negative or the same. The torque converter 2 is provided with a mechanical oil pump (hydraulic pressure generating source) 27 that is connected to and driven by the pump impeller 21.

-Forward / reverse switching device-
The forward / reverse switching device 3 includes a double pinion type planetary gear mechanism 30, a forward clutch (input clutch) C1, and a reverse brake B1.

  The sun gear 31 of the planetary gear mechanism 30 is integrally connected to the turbine shaft 28 of the torque converter 2, and the carrier 33 is integrally connected to the input shaft 40 of the belt type continuously variable transmission 4. The carrier 33 and the sun gear 31 are selectively connected via the forward clutch C1, and the ring gear 32 is selectively fixed to the housing via the reverse brake B1.

  The forward clutch C1 and the reverse brake B1 are hydraulic friction engagement elements that are engaged and released by the hydraulic control circuit 20, and the forward clutch C1 is engaged and the reverse brake B1 is released. As a result, the forward / reverse switching device 3 is integrally rotated to establish (achieve) the forward power transmission path. In this state, the forward driving force is transmitted to the belt type continuously variable transmission 4 side.

  On the other hand, when the reverse brake B1 is engaged and the forward clutch C1 is released, the forward / reverse switching device 3 establishes (achieves) a reverse power transmission path. In this state, the input shaft 40 rotates in the reverse direction with respect to the turbine shaft 28, and the driving force in the reverse direction is transmitted to the belt type continuously variable transmission 4 side. Further, when both the forward clutch C1 and the reverse brake B1 are released, the forward / reverse switching device 3 becomes neutral (interrupted state) for interrupting power transmission.

-Belt type continuously variable transmission-
The belt-type continuously variable transmission 4 includes an input-side primary pulley 41, an output-side secondary pulley 42, a metal belt 43 wound around the primary pulley 41 and the secondary pulley 42, and the like.

  The primary pulley 41 is a variable pulley having a variable effective diameter, and a fixed sheave 411 fixed to the input shaft 40 and a movable sheave 412 disposed on the input shaft 40 in a state in which sliding is possible only in the axial direction. And is composed of. Similarly, the secondary pulley 42 is a variable pulley whose effective diameter is variable, and is a fixed sheave 421 fixed to the output shaft 44 and a movable sheave arranged on the output shaft 44 so as to be slidable only in the axial direction. 422.

  A hydraulic actuator 413 for changing the V groove width between the fixed sheave 411 and the movable sheave 412 is disposed on the movable sheave 412 side of the primary pulley 41. Similarly, a hydraulic actuator 423 for changing the V groove width between the fixed sheave 421 and the movable sheave 422 is also arranged on the movable sheave 422 side of the secondary pulley 42.

  In the belt type continuously variable transmission 4 having the above-described structure, by controlling the hydraulic pressure of the hydraulic actuator 413 of the primary pulley 41, the V groove widths of the primary pulley 41 and the secondary pulley 42 change, and the engagement diameter of the belt 43 ( The effective diameter is changed, and the speed ratio γ (speed ratio γ = input shaft speed Nin / output shaft speed Nout) continuously changes. The hydraulic pressure of the hydraulic actuator 423 of the secondary pulley 42 is controlled such that the belt 43 is clamped with a predetermined clamping pressure that does not cause belt slip. These controls are executed by the ECU 8 and the hydraulic control circuit 20 (see FIG. 3).

  The hydraulic control circuit 20 is provided with a linear solenoid valve, an on / off solenoid valve, and the like. By controlling the excitation / non-excitation of these solenoid valves and switching the hydraulic circuit, the shift control of the belt type continuously variable transmission 4 is performed. And engage / release control of the lock-up clutch 24. Excitation / non-excitation of the linear solenoid valve and the on / off solenoid valve of the hydraulic control circuit 20 is controlled by a solenoid control signal (instructed hydraulic signal) from the ECU 8. A specific configuration and operation of the lockup control circuit 200 for performing engagement / release control of the lockup clutch 24 will be described below.

-Lock-up control circuit-
FIG. 2 is a circuit diagram showing the lockup control circuit 200 that performs engagement / release control of the lockup clutch 24 in the hydraulic control circuit 20.

  The lockup control circuit 200 includes a lockup control valve 201, a pressure regulating valve 220, a linear solenoid valve (SLU solenoid valve) 230 for lockup differential pressure control, and the like.

  The lockup control valve 201 is provided with a pair of first line pressure port 202 and second line pressure port 203, and further provided with a release side port 205 and a signal pressure port 206. The original pressure (lock-up pressure) PL from the pressure regulating valve 220 is supplied to the first line pressure port 202 and the second line pressure port 203. The pressure regulating valve 220 regulates the control pressure (line pressure) in the hydraulic control circuit 20 (see FIG. 3) and supplies it to the lockup control valve 201 and the engagement side oil chamber 25 of the torque converter 2. Further, the release side port 205 of the lockup control valve 201 is connected to the release side oil chamber 26 of the torque converter 2.

  The SLU solenoid valve 230 is a linear solenoid valve, and outputs the control signal pressure PSLU when in an excited state, and stops outputting the control signal pressure PSLU when in a non-excited state. In this SLU solenoid valve 230, the excitation current is duty-controlled in accordance with the lockup differential pressure instruction value PD output from the ECU 8, and the control signal pressure PSLU continuously changes. The control signal pressure PSLU output from the SLU solenoid valve 230 is supplied to the signal pressure port 206 of the lockup control valve 201.

  In the lockup control circuit 200 described above, the SLU solenoid valve 230 is excited in accordance with the lockup differential pressure instruction value PD output from the ECU 8, and the control signal pressure PSLU is supplied to the signal pressure port 206 of the lockup control valve 201. Then, in this lockup control valve 201, as shown in the right half of the center line in FIG. 2, the spool 207 is moved upward against the urging force of the compression coil spring 208 (ON state). In this state, the release-side port 205 communicates with the drain port 209 while the lock-up pressure PL is supplied to the engagement-side oil chamber 25 of the torque converter 2, so that the hydraulic oil in the release-side oil chamber 26 is obtained. Is drained and the lock-up clutch 24 is engaged (ON).

  At this time, the lockup differential pressure PLU, that is, the hydraulic pressure Pon in the engagement-side oil chamber 25 of the lockup clutch 24 and the release-side oil chamber 26 according to the duty ratio of the lockup differential pressure instruction value PD output from the ECU 8. The differential pressure with respect to the internal hydraulic pressure Poff can be continuously controlled, and the engagement force of the lockup clutch 24 can be continuously changed according to the lockup differential pressure PLU.

  On the other hand, when the SLU solenoid valve 230 is de-energized and the output of the control signal pressure PSLU from the SLU solenoid valve 230 is stopped, the lockup control valve 201 is compressed as shown in the left half of the center line in FIG. The spool 207 is moved downward by the urging force of the coil spring 208 and is moved to the original position (OFF state).

  In this OFF state, the second line pressure port 203 and the release side port 205 communicate with each other, and the lockup pressure PL is supplied to the release side oil chamber 26 of the lockup clutch 24 via these ports 203 and 205. Thus, the hydraulic pressure in the release-side oil chamber 26 and the hydraulic pressure in the engagement-side oil chamber 25 are equalized, and the lockup clutch 24 is released (OFF).

-ECU-
As shown in FIG. 3, the ECU 8 includes a CPU 81, a ROM 82, a RAM 83, a backup RAM 84, and the like.

  The ROM 82 stores various control programs, maps that are referred to when the various control programs are executed, and the like. The CPU 81 executes arithmetic processing based on various control programs and maps stored in the ROM 82. The RAM 83 is a memory for temporarily storing calculation results in the CPU 81 and data input from each sensor. The backup RAM 84 is a non-volatile memory for storing data to be saved when the engine 1 is stopped. is there.

  The CPU 81, ROM 82, RAM 83, and backup RAM 84 are connected to each other via a bus 87 and are connected to an input interface 85 and an output interface 86.

  The input interface 85 of the ECU 8 includes an engine speed sensor 101, a throttle opening sensor 102, a water temperature sensor 103, a turbine speed sensor 104, an input shaft speed sensor 105, a vehicle speed sensor 106, an accelerator opening sensor 107, and a CVT oil temperature. A sensor 108, a brake pedal sensor 109, and a lever position sensor 110 that detects a lever position (operation position) of the shift lever 9 are connected. The input interface 85 allows the output signal of each sensor, that is, the rotation speed of the engine 1 (engine rotation speed) Ne, the opening degree θth of the throttle valve 12, the cooling water temperature Tw of the engine 1, the rotation speed of the turbine shaft 28 ( Turbine speed Nt, input shaft 40 speed (input shaft speed) Nin, vehicle speed V, accelerator pedal operation amount (accelerator opening) Acc, oil pressure of hydraulic control circuit 20 (CVT oil) The ECU 8 is supplied with signals indicating the temperature Thc), the presence / absence of operation of the foot brake as a service brake (brake ON / OFF), the lever position (operation position) of the shift lever 9, and the like. The output interface 86 is connected to the throttle motor 13, the fuel injection device 14, the ignition device 15, the hydraulic control circuit 20 (lockup control circuit 200), and the like.

  Here, of the signals supplied to the ECU 8, the turbine rotational speed Nt coincides with the input shaft rotational speed Nin during forward travel where the forward clutch C1 of the forward / reverse switching device 3 is engaged, and the vehicle speed V is the belt type This corresponds to the rotational speed (output shaft rotational speed) Nout of the output shaft 44 of the step transmission 4. The accelerator operation amount Acc represents the driver's requested output amount.

  The shift lever 9 includes a parking position “P” for parking, a reverse position “R” for reverse traveling, a neutral position “N” for interrupting power transmission, a drive position “D” for forward traveling, During forward running, the gear ratio γ of the belt type continuously variable transmission 4 is selectively operated to each position such as a manual position “M” where the manual operation can increase or decrease the speed ratio γ.

  The manual position “M” includes a plurality of ranges in which a downshift position and an upshift position for increasing / decreasing the speed ratio γ, or a plurality of speed ranges in which the upper limit of the speed range (the side where the speed ratio γ is smaller) are different can be selected Position etc. are provided.

  The lever position sensor 110 is, for example, a parking position “P”, a reverse position “R”, a neutral position “N”, a drive position “D”, a manual position “M”, an upshift position, a downshift position, or a range position. A plurality of ON / OFF switches for detecting that the shift lever 9 is operated are provided. In order to change the gear ratio γ manually, a downshift switch, an upshift switch (so-called paddle switch), a lever, or the like can be provided on the steering wheel or the like separately from the shift lever 9.

  The ECU 8 controls the output of the engine 1, the shift control of the belt-type continuously variable transmission 4, the belt clamping pressure control, and the engagement / disengagement of the lock-up clutch 24 based on the output signals of the various sensors described above. Perform release control. Further, the ECU 8 performs deceleration lock-up control, lock-up smooth engagement control (hydraulic control to avoid a shock when the lock-up clutch 24 is engaged), lock-up smooth OFF control (when releasing the lock-up clutch 24). (Hydraulic control to avoid shock)). Since the deceleration lockup control, the lockup smooth engagement control, and the lockup smooth OFF control are already known, the description thereof is omitted here.

  Output control of the engine 1 is performed by the throttle motor 13, the fuel injection device 14, the ignition device 15, the ECU 8, etc., and the shift control of the belt type continuously variable transmission 4, the belt clamping pressure control, and the engagement of the lockup clutch 24. The release control is performed by the hydraulic control circuit 20 (lock-up control circuit 200). The throttle motor 13, the fuel injection device 14, the ignition device 15, and the hydraulic control circuit 20 are controlled by the ECU 8.

  For example, as shown in FIG. 4, the shift control of the belt-type continuously variable transmission 4 is performed based on a target shift on the input side from a shift map set in advance with the accelerator operation amount Acc representing the driver's required output amount and the vehicle speed V as parameters. The number (target rotational speed) Nint is calculated, and the shift control of the belt-type continuously variable transmission 4 according to the deviation, that is, the primary pulley 41 so that the actual input shaft rotational speed Nin matches the target rotational speed Nint. The hydraulic pressure Pin is controlled by supplying and discharging the hydraulic oil to and from the hydraulic actuator 413, and the gear ratio γ continuously changes.

  The map in FIG. 4 corresponds to the shift conditions, and the target rotational speed Nint is set such that the greater the vehicle speed V is and the accelerator operation amount Acc is, the greater the gear ratio γ is. Further, since the vehicle speed V corresponds to the output shaft rotational speed Nout, the target rotational speed Nint, which is the target value of the input shaft rotational speed Nin, corresponds to the target speed ratio, and the minimum speed ratio γmin of the belt type continuously variable transmission 4 is It is set within the range of the maximum gear ratio γmax.

  In the basic control for engaging / releasing the lockup clutch 24, for example, as shown in FIG. 5, based on a switching map (switching condition) stored in advance using the throttle valve opening θth corresponding to the input torque and the vehicle speed V as parameters. Thus, the engagement / release of the lockup clutch 24 is switched according to the actual throttle valve opening θth and the vehicle speed V.

  In the switching map shown in FIG. 5, an engagement switching line indicated by a solid line and a release switching line indicated by a broken line are set with a predetermined hysteresis. In the switching map shown in FIG. 5, since the lockup clutch 24 is in the released state (OFF), the vehicle speed V changes to the high vehicle speed side, or the throttle opening θth changes to the low throttle opening side. When the joint switching line (solid line) is crossed, the lockup clutch 24 is switched to the engaged state (ON). On the other hand, when the lockup clutch 24 is in the engaged state (ON), the vehicle speed V changes to the low vehicle speed side, or the throttle opening degree θth changes to the high throttle opening side so that the release switching line (broken line) When the vehicle crosses, the lockup clutch 24 is switched to the released state (OFF).

-Slip start control-
Next, an outline of the slip start control will be described. In this slip start control, when the vehicle starts, the lockup differential pressure PLU is gradually increased to bring the lockup clutch 24 into a semi-engagement state. At the same time, power transmission loss in the torque converter 2 is reduced, and a sudden increase (so-called soaring) of the engine speed Ne is suppressed, so that the fuel consumption rate can be improved.

  Specifically, when the vehicle speed is “0” by the output signal from the vehicle speed sensor 106 and the brake pedal is not operated by the output signal from the brake pedal sensor 109, the accelerator opening sensor 107 is set. When it is detected that the accelerator opening Acc is increased from “0” by the output signal from the vehicle, it is determined that the vehicle is starting. Along with this start determination, the ECU 8 outputs the lockup differential pressure instruction value PD at a predetermined duty ratio, and accordingly, the lockup differential pressure PLU, that is, the hydraulic pressure Pon in the engagement side oil chamber 25 of the lockup clutch 24. And the hydraulic pressure Poff in the release-side oil chamber 26 is continuously controlled (lockup differential pressure), and the engagement force of the lockup clutch 24 is continuously controlled according to the lockup differential pressure PLU. (A torque capacity is generated in the lockup clutch 24). That is, the vehicle starts with the lock-up clutch 24 in the half-engaged state.

  In this embodiment, as will be described later, when starting the vehicle, the slip start control is not always performed, but when a predetermined slip start control permission condition (completion of a plurality of hydraulic pressure learning operations) is satisfied. Only when the vehicle starts, slip start control is performed. Details will be described later.

  FIG. 6 is a diagram showing the relationship between the lockup differential pressure command value PD and the lockup differential pressure PLU when the slip start control is executed. As shown in FIG. 6, due to individual differences at the time of manufacturing the SLU solenoid valve 230, characteristic changes associated with long-term use, etc., the characteristics of generating a lockup differential pressure (timing at which torque capacity is generated: lockup Variation occurs in the lockup differential pressure instruction value PD generated by the differential pressure PLU. The solid line in FIG. 6 indicates the relationship between the lock-up differential pressure command value PD and the lock-up differential pressure PLU when the lock-up differential pressure is generated at a proper timing, that is, at a proper timing. In this case, from the start of transmission of the lockup differential pressure command value PD, the lockup differential pressure command value PD gradually increases, and at time T0, the lockup differential pressure PLU is generated and the torque capacity of the lockup clutch 24 is increased. Will occur. When the torque capacity is generated at this timing T0, the vehicle can be started without causing a rapid decrease or increase in the engine speed.

  On the other hand, the generation characteristics of the lockup differential pressure PLU may vary within the range indicated by each broken line. In the upper limit product in the figure, the generation timing of the lockup differential pressure PLU (the generation timing of the torque capacity of the lockup clutch) is earlier than the appropriate timing (elapsed time since the start of transmission of the lockup differential pressure command value PD) The lockup differential pressure PLU is generated at a timing T1 that is shorter than the appropriate time, and the torque capacity is generated in the lockup clutch 24). In this case, the engine speed rapidly decreases, and in some cases, the engine stalls. There is a possibility of reaching.

  On the other hand, in the lower limit product in the figure, the generation timing of the lockup differential pressure PLU is later than the appropriate timing (timing T2 in which the elapsed time from the start of transmission of the lockup differential pressure command value PD is longer than the appropriate time) The lockup differential pressure PLU is generated and the torque capacity is generated in the lockup clutch 24). In this case, the engine speed rapidly increases until the torque capacity is obtained, leading to deterioration of the fuel consumption rate. The purpose of slip start control may not be achieved.

  For this reason, in order to generate the lockup differential pressure at an appropriate timing, it is necessary to correct the lockup differential pressure instruction value PD by learning the hydraulic pressure.

  However, as described above, when the learning operation is performed at the start of the slip start control, the amount of change in engine torque per unit time and the amount of change in engine speed per unit time are large, and turbine rotation relative to engine speed Due to the small number ratio (speed ratio), torque capacity is generated due to the influence of centrifugal oil pressure generated inside the torque converter 2, and sufficient learning accuracy cannot be obtained.

  Therefore, in this embodiment, permission conditions for performing slip start control are set as described below, and slip start control is permitted only when the permission conditions are satisfied.

−Slip start control execution permission operation−
Next, the slip permission control execution permission operation, which is an operation characteristic of the present embodiment, will be described. The outline of the slip start control execution permission operation will be described. When the vehicle starts, it is determined whether or not the slip start control permission condition is satisfied, and if the permission condition is not satisfied, the slip start control is performed. Prohibit control. That is, the vehicle is started with the lock-up clutch 24 released. On the other hand, if the permit condition for the slip start control is satisfied, the slip start control is permitted. That is, when the vehicle starts, the lockup clutch 24 is brought into a half-engaged state. The permit condition for the slip start control is satisfied when the oil pressure learning of the lockup clutch 24 is executed a predetermined number of times, and this oil pressure learning is performed for a predetermined period immediately after the vehicle starts (originally, the slip start control is performed. It is executed in a period other than (period). In other words, after completion of oil pressure learning during lock-up control during steady vehicle travel (when the oil pressure learning operation has been executed a predetermined number of times), execution of slip start control during vehicle start-up is permitted.

  FIG. 7 is a flowchart showing the procedure of the slip start control execution permission operation. This flowchart is executed every several msec or every predetermined rotation angle of the crankshaft after the engine 1 is started. Further, a hydraulic pressure learning completion flag, which will be described later, is reset to “0”, for example, every time the travel distance of the vehicle reaches a predetermined distance (for example, every 1000 km travel distance). That is, in the routine of FIG. 7 repeated every predetermined period, the hydraulic pressure learning completion flag is periodically reset to “0”. The above value (traveling distance 1000 km) is not limited to this, and can be arbitrarily set. However, if this value is too small, the opportunity for executing the slip start control is reduced, and if it is too large, the SLU solenoid valve 230 is set. There is a possibility that the slip start control may be executed in a state in which an appropriate lockup differential pressure cannot be obtained due to a change in the characteristics over time. For this reason, this value is set in consideration of these.

  First, in step ST1, it is determined whether or not the hydraulic pressure learning completion flag is set to “1”. In the first routine of this flowchart (routine executed immediately after the travel distance of the vehicle reaches the predetermined distance), the oil pressure learning completion flag is reset to “0”, so NO is determined in step ST1, Move on to step ST2. In step ST2, it is determined whether or not normal lockup control has been performed. This normal lockup control is a lockup control at a timing different from the lockup control performed when the slip start control is executed. For example, the vehicle speed and the throttle opening (or the accelerator opening) are parameters. This is done according to the lockup switching map.

  If the normal lockup control is not performed and a NO determination is made in step ST2, the process directly returns. On the other hand, when the normal lockup control is performed and YES is determined in step ST2, the process proceeds to step ST3, where the learned value is acquired by executing the hydraulic pressure learning operation (lockup clutch hydraulic pressure learning by the hydraulic pressure learning means). ).

  Hereinafter, an outline of the hydraulic pressure learning operation will be described. FIG. 8 shows the accelerator opening, the engine speed, the turbine speed, the torque capacity of the lockup clutch when the normal lockup control is performed after a predetermined time from the vehicle start and the hydraulic pressure learning operation is performed accordingly. It is a timing chart figure showing an example of change of each of lockup differential pressure directions and lockup actual differential pressure.

  This learning operation is started when the speed ratio (ratio of turbine speed to engine speed) becomes a predetermined value (for example, 0.8) or more. This value is not limited to this, and is set experimentally or by simulation as a gear ratio that does not generate torque capacity due to the centrifugal hydraulic pressure generated inside the torque converter 2.

  First, when the accelerator pedal is depressed at the timing t1 in the figure, the vehicle starts, and at the timing t2, the speed ratio reaches the predetermined value or more. At this timing t2, a lockup differential pressure instruction is output. Then, due to the variation in the characteristics of the SLU solenoid valve 230, the actual lockup differential pressure increases from the timing t3, and accordingly, a torque capacity is generated in the lockup clutch 24. The waveform shown in FIG. 8 shows a case where the generation timing of the actual lockup differential pressure is delayed from the appropriate timing (the generation timing of the nominal product) due to variations in the characteristics of the SLU solenoid valve 230.

  The torque capacity of the lockup clutch 24 reaches a preset determination threshold at timing t4. In this learning operation, a period from when the lockup differential pressure instruction is output until the torque capacity of the lockup clutch reaches the above-described determination threshold (period from timing t2 to t4) is referred to as “actual dead time”. A learning value is obtained such that the “actual waste time” matches the target “target waste time (dead time in nominal product)”, and the lockup differential pressure instruction is corrected according to the learned value. Note that the change in torque capacity (target torque capacity change) of the lock-up clutch 24 indicated by a two-dot chain line in FIG. 8 indicates that of the nominal product.

  The torque capacity of the lockup clutch is calculated by repeating the calculation in the following formula (1) at predetermined time intervals, and the time when the torque capacity of the lockup clutch reaches the determination threshold (timing t4) Will be judged.

TCL = Te−C · Ne ² −Ie · ΔNe (1)
In this equation (1), TCL is the torque capacity of the lockup clutch, Te is the torque of the engine, C is the capacity coefficient of the torque converter, Ne is the engine speed, Ie is the inertia of the engine, and ΔNe is per unit time of the engine speed. Is the amount of change.

  As shown in FIG. 8, when the “actual dead time” is longer than the “target wasted time”, the lockup differential pressure instruction is increased (lock up) so as to shorten the “actual dead time”. If the "actual dead time" is shorter than the "target wasted time", the lock is made to extend this "actual wasted time". The up differential pressure instruction is corrected to a smaller side (the generation timing of the torque capacity of the lockup clutch is delayed). Such correction of the lockup differential pressure instruction is performed every time the lockup control is performed. For this reason, when the lockup control is performed a plurality of times, the learned lockup differential pressure instruction value gradually converges to an appropriate value, and the “actual waste time” substantially matches the “target waste time”. become.

  After the hydraulic pressure learning operation is executed to acquire the learning value, the process proceeds to step ST4, and the hydraulic pressure learning execution number Ng is incremented by “1”. Thereafter, the process proceeds to step ST5, where it is determined whether or not the hydraulic pressure learning execution number Ng has reached a predetermined number α (for example, five times). The number of times is not limited to this, and is set as the number of times that the reliability of the learning value can be sufficiently secured.

  In the first routine, the oil pressure learning execution number Ng has not yet reached the predetermined number α, so a NO determination is made in step ST5 and the process returns.

  When such an operation is performed a plurality of times (every time normal lockup control is performed) and the oil pressure learning execution number Ng reaches the predetermined number α, and YES is determined in step ST5, the process proceeds to step ST6. The oil pressure learning completion flag is set to “1”.

  In the next routine after the hydraulic pressure learning completion flag is set to “1” in this way, YES is determined in step ST1, and the process proceeds to step ST7. In step ST7, it is determined whether or not the vehicle is starting. That is, as described above, the accelerator opening degree sensor 107 is in a state where the vehicle speed is “0” by the output signal from the vehicle speed sensor 106 and the brake pedal is not operated by the output signal from the brake pedal sensor 109. It is determined whether or not the accelerator opening degree Acc is increased from “0” based on the output signal from.

  If it is not at the time of starting the vehicle, NO is determined in step ST7, and the process returns as it is. In this case, the hydraulic pressure learning completion flag is continuously maintained at “1”. On the other hand, when the vehicle is starting and the determination is YES in step ST7, the process proceeds to step ST8 and the slip start control is executed. That is, the vehicle is started with the lock-up clutch 24 in a semi-engaged state (permission of execution of slip start control by the slip start control permission means). When the vehicle starts thereafter, slip start control is always performed when the vehicle starts until the hydraulic pressure learning completion flag is reset to “0”.

  As described above, since the hydraulic pressure learning is performed in a period other than the period in which the slip start control is originally performed, the acquired learning value is a value other than a transient time (at the time of vehicle start) in which the engine torque and the engine speed greatly vary. It is acquired at the timing, and its reliability is sufficiently secured. Further, since the hydraulic pressure learning described above starts when the speed ratio (ratio of the turbine rotational speed to the engine rotational speed) becomes equal to or higher than a predetermined value, the influence of centrifugal hydraulic pressure generated inside the torque converter 2 is affected. The learning value is acquired in a situation where the torque capacity due to is not generated, and the reliability of the learning value can also be obtained with this.

  And since slip start control is performed by the lockup differential pressure instruction | indication value learning-corrected by this highly reliable learning value, lockup differential pressure is an appropriate timing (timing substantially the same as the said nominal product). Will be set to. As a result, a sudden decrease in engine speed due to the occurrence of the lockup differential pressure being too early and a sudden increase in engine speed due to the occurrence of the lockup differential pressure being too late are avoided, preventing engine stall and fuel. The consumption rate can be improved.

  FIG. 9 shows the accelerator opening, the engine speed, the turbine speed, the torque capacity of the lockup clutch, the lockup differential pressure instruction, when the slip start control is executed after the learning operation is completed in this way, It is a timing chart figure showing an example of change of each lockup actual differential pressure. A region indicated by a broken line in the drawing indicates a correction amount in which the lockup differential pressure instruction is corrected by the above-described learning operation. The amount of learning correction shown in FIG. 9 is corrected for increase. That is, as shown in FIG. 8, this is a learning correction amount when the generation timing of the actual lockup differential pressure is delayed from the appropriate timing (the generation timing of the nominal product). On the other hand, when the generation timing of the actual lockup differential pressure is earlier than the appropriate timing, the learning correction is reduced.

  As can be seen from the engine speed waveform in FIG. 9, the learning operation generates a lock-up differential pressure (actual differential pressure) at an appropriate timing, and the engine speed does not drop or rise rapidly.

  The waveform indicated by the alternate long and short dash line in FIG. 9 shows changes in the engine speed and the torque capacity of the lockup clutch when the slip start control is not executed (the lockup clutch 24 is turned OFF). Yes.

-Other embodiments-
In the embodiment described above, the case where the present invention is applied to a vehicle equipped with a belt type continuously variable transmission (CVT) as a transmission has been described. The present invention is not limited to this, and can also be applied to a vehicle equipped with a planetary gear type transmission.

  In the above embodiment, the case where the present invention is applied to an FF (front engine / front drive) vehicle has been described. However, the present invention is also applied to an FR (front engine / rear drive) vehicle or a four-wheel drive vehicle. Is applicable.

  In the above-described embodiment, the case where the present invention is applied to an automobile equipped with the gasoline engine 1 has been described. The present invention is not limited to this, and can also be applied to an automobile equipped with a diesel engine. Further, the number of cylinders and the engine type (V type, horizontally opposed type, etc.) are not particularly limited.

  The present invention provides a start control for realizing a slip start control according to a highly accurate hydraulic pressure learning value for a vehicle capable of executing a slip start control in which a lock-up clutch is half-engaged with the start of the vehicle. It is applicable to.

1 Engine (Power source for running)
11 Crankshaft 2 Torque converter (fluid power transmission device)
21 pump impeller 22 turbine runner 24 lockup clutch 25 engagement side oil chamber 26 release side oil chamber 28 turbine shaft 4 belt type continuously variable transmission (automatic transmission)
8 ECU

Claims (8)

In a vehicle control device capable of slip start control when starting a vehicle and lock-up control during steady running of the vehicle,
A control apparatus for a vehicle, characterized in that execution of slip start control is permitted after completion of oil pressure learning during the lockup control. A vehicle control device having a fluid type power transmission device with a lock-up clutch between a driving power source and an automatic transmission, and capable of slip start control for bringing the lock-up clutch into a semi-engaged state when starting In
Oil pressure learning means for performing lockup clutch oil pressure learning at the time of lockup control during vehicle travel after a predetermined period of time has passed since the start of the vehicle;
The slip start control execution is prohibited until the lock start clutch hydraulic pressure learning executed by the hydraulic pressure learning means is completed and the slip start control execution permission condition is satisfied, and the slip start control execution permission condition is satisfied. A vehicle control apparatus comprising slip start control permission means for permitting execution of slip start control. The vehicle control device according to claim 1,
Completion of the oil pressure learning during the lockup control is established by performing the oil pressure learning operation a predetermined number of times. The vehicle control device according to claim 2,
The vehicle control apparatus according to claim 1, wherein the slip start control execution permission condition is satisfied when the lockup clutch hydraulic pressure learning is performed a predetermined number of times. In the vehicle control apparatus according to any one of claims 1 to 4,
In the hydraulic pressure learning, the ratio of the input shaft rotational speed to the output shaft rotational speed of the lockup clutch is such that the torque capacity of the lockup clutch is not generated due to the centrifugal hydraulic pressure generated inside the fluid power transmission device. A control device for a vehicle, which is executed when the value exceeds a value. The vehicle control device according to claim 1 or 3,
It is configured to prohibit the execution of slip start control every time the mileage of the vehicle reaches a predetermined distance, and then permit the execution of slip start control again after completion of oil pressure learning during the lockup control. A vehicle control device. The vehicle control device according to claim 2 or 4,
The slip start control permission unit makes the slip start control execution permission condition unsatisfied every time the travel distance of the vehicle reaches a predetermined distance, and then the lockup clutch hydraulic pressure learning executed by the hydraulic pressure learning unit is completed and then again. A control apparatus for a vehicle, characterized in that execution of slip start control is permitted when a slip start control execution permission condition is satisfied. In the vehicle control device according to any one of claims 1 to 7,
The oil pressure learning is calculated by calculating the torque capacity of the lockup clutch,
TCL = Te−C · Ne ² −Ie · ΔNe (1)
TCL is the torque capacity of the lockup clutch, Te is the engine torque, C is the capacity coefficient of the torque converter, Ne is the engine speed, Ie is the engine inertia, ΔNe is the amount of change in the engine speed per unit time,
By calculating the torque capacity of the lock-up clutch by means of, the vehicle control device is configured to learn the generation time of the torque capacity of the lock-up clutch.

Images