JP6954743B2 - Vehicle control device - Google Patents

Description

The present invention relates to a vehicle control device and relates to slip control of a lockup clutch that directly connects an input member and an output member of a torque converter during shifting of an automatic transmission.

An engine, an automatic transmission, a torque converter provided between the engine and the automatic transmission, a lockup clutch that directly connects an input member and an output member of the torque converter to the torque converter, and the lock. A vehicle control device including a lock-up clutch slip control device for controlling the difference rotation between the input member and the output member of the up-clutch, wherein a predetermined first target input rotation speed is set to the current speed. A vehicle control device that controls slip of a lockup clutch by replacing it with a second target input rotation speed obtained from the output rotation speed of the lockup clutch and the target slip ratio after shifting is known. For example, the vehicle control device of Patent Document 1 is that. In the vehicle control device of Patent Document 1, by improving the accuracy of the slip control of the lockup clutch during shifting of the automatic transmission, shock suppression at the completion of shifting, that is, improvement of drivability and slip of the lockup clutch can be achieved. We are trying to suppress the increase in fuel consumption caused by the large size.

Japanese Unexamined Patent Publication No. 2014-20416

However, in the vehicle control device of Patent Document 1, since the difference in the requirement for slip control due to the difference between the driving mode such as sports mode, normal mode and eco mode and the difference in shifting such as upshift and downshift is not taken into consideration, the driver The improvement of performance and the improvement of fuel efficiency were insufficient.

The present invention has been made in the background of the above circumstances, and an object of the present invention is to control slip in a difference between a driving mode such as a sports mode, a normal mode, and an eco mode and a shift such as an upshift and a downshift. It is an object of the present invention to provide a vehicle control device capable of improving drivability and fuel efficiency by implementing control that reflects the difference in requirements.

The gist of the first invention is (a) an engine, an automatic transmission, a torque converter provided between the engine and the automatic transmission, an input member of the torque converter, and the torque converter. A vehicle control device including a lockup clutch that directly connects an output member and a lockup clutch slip control device that controls a differential rotation between the input member and the output member of the lockup clutch. (B) When the shift of the automatic transmission is started during the complete lockup control or the flex lockup control of the lockup clutch, the shift stage and the vehicle before and after the shift are switched by the shift. The shift time required for the shift is calculated based on the traveling mode, and the longer the shift time, the larger the target difference rotation between the input member and the output member of the lockup clutch is set.

According to the present invention, when the shift of the automatic transmission is started during the complete lockup control or the flex lockup control of the lockup clutch, the shift stages before and after the shift are switched by the shift. The shift time required for the shift is calculated based on the above and the traveling mode of the vehicle, and the longer the shift time, the larger the target difference rotation between the input member and the output member of the lockup clutch is set. It is possible to reflect the difference in demand for slip control between the driving mode such as mode, normal mode and eco mode and the difference in shifting such as upshift and downshift, which improves drivability by reducing the shock when shifting is completed. And improvement of fuel efficiency can be appropriately implemented.

It is a figure explaining the schematic structure of the vehicle to which this invention is applied, and also is the figure explaining the control function for various control in a vehicle. It is a skeleton diagram explaining an example of the torque converter and the automatic transmission provided in the vehicle of FIG. It is an engagement operation table explaining the relationship between the shift operation of the automatic transmission of FIG. 2 and the operation of the hydraulic friction engagement device used therefor. It is a circuit diagram which shows an example of the main part of the hydraulic control circuit concerning the lockup clutch provided in the torque converter of FIG. 2, the linear solenoid valve which controls the operation of the lockup clutch, and the like. It is an example of a time chart, and is a figure explaining the hydraulic pressure at the time of movement of the friction plate of a lockup clutch. It is a figure which showed the engine rotation speed, the turbine rotation speed, and the difference rotation speed at the time of changing the instruction hydraulic pressure to the lockup clutch in the slip control of the lockup clutch during shifting of an automatic transmission. It is a flowchart explaining the main part of the control operation of the electronic control device of FIG. 1, that is, the basic operation of the shift of an automatic transmission and the lockup clutch control.

Hereinafter, examples of the present invention will be described in detail with reference to the drawings. In the following examples, the drawings are appropriately simplified or deformed, and the dimensional ratios and shapes of each part are not necessarily drawn accurately.

FIG. 1 is a diagram for explaining a schematic configuration of a vehicle 10 to which the present invention is applied, and is a diagram for explaining a main part of a control system for various controls in the vehicle 10. In FIG. 1, the vehicle 10 includes an engine 12, drive wheels 14, and a power transmission device 16 provided in a power transmission path between the engine 12 and the drive wheels 14. The power transmission device 16 includes a torque converter 20 and an automatic transmission 22 arranged in a case 18 (see FIG. 2) as a non-rotating member attached to a vehicle body, and a transmission which is an output rotating member of the automatic transmission 22. The output gear 24 includes a differential gear device 26 connected to the ring gear 26a, a pair of axles 28 connected to the differential gear device 26, and the like. In the automatic transmission 22, the power output from the engine 12 is transmitted from the crank shaft 12a (see FIG. 2) to the drive wheels 14 via the torque converter 20, the automatic transmission 22, the differential gear device 26, the axle 28, and the like. Is transmitted to. Further, the torque converter 20 is provided in the power transmission path between the automatic transmission 22 and the engine 12.

The engine 12 is a power source for the vehicle 10, and is an internal combustion engine such as a gasoline engine or a diesel engine.

FIG. 2 is a skeleton diagram illustrating an example of a torque converter 20 and an automatic transmission 22. The torque converter 20, the automatic transmission 22, and the like are configured substantially symmetrically with respect to the axial center RC of the turbine shaft 30, which is an input rotating member of the automatic transmission 22, and in FIG. 2, the axial center RC is configured. The lower half is omitted.

The torque converter 20 includes a pump impeller 20p corresponding to an input member connected to the engine 12 and a turbine impeller 20t connected to a turbine shaft 20 corresponding to an output member. The pump impeller 20p is used to control the speed change of the automatic transmission 22, switch the operations of the forward clutch C1 and the reverse brake B1 described later, and supply lubricating oil to each part of the power transmission device 16. A mechanical oil pump 33 generated by rotationally driving the hydraulic pressure for this purpose by the engine 12 is connected. Further, the torque converter 20 is provided with a lockup clutch 32 capable of connecting and disconnecting between the pump impeller 20p and the turbine impeller 20t.

The automatic transmission 22 constitutes a part of the power transmission path from the engine 12 to the drive wheels 14, and a plurality of hydraulic friction engaging devices (first clutch C1 to fourth clutch C4, first brake B1, second). It functions as a stepped automatic transmission in which a plurality of gears (shifts) having different gear ratios (gear ratios) are formed by selectively engaging either the brake B2) or the one-way clutch F1. It is a planetary gear type multi-speed transmission. For example, it is a stepped transmission that performs so-called clutch-to-clutch shifting, which is often used in vehicles. The automatic transmission 22 has a double pinion type first planetary gear device 58, a single pinion type second planetary gear device 60 configured in a labinyo type, and a double pinion type third planetary gear device 62 on a coaxial line. It is held (on the axis RC), and the rotation of the turbine shaft 30 is changed and output from the transmission output gear 24.

The first planetary gear device 58 includes a first sun gear S1 which is an external gear, a first ring gear R1 which is an internal gear arranged concentrically with the first sun gear S1, and a first sun gear S1 and a first ring gear R1. It has a first pinion gear P1 composed of a pair of gears that mesh with the gears, and a first carrier CA1 that supports the first pinion gear P1 so as to rotate and revolve.

The second planetary gear device 60 includes a second sun gear S2 which is an external gear, a second ring gear R2 which is an internal gear arranged concentrically with the second sun gear S2, a second sun gear S2, and a second ring gear R2. It has a second pinion gear P2 that meshes with the second pinion gear P2 and a second carrier CA2 that supports the second pinion gear P2 so as to rotate and revolve.

The third planetary gear device 62 includes a third sun gear S3 which is an external gear, a third ring gear R3 which is an internal gear arranged concentrically with the third sun gear S3, and the third sun gear S3 and the third ring gear. It has a third pinion gear P3 composed of a pair of gears that meshes with R3, and a third carrier CA3 that supports the third pinion gear P3 so that it can rotate and revolve.

The first clutch C1, the second clutch C2, the third clutch C3, the fourth clutch C4, and the first brake B1, the second brake B2 (hereinafter, unless otherwise specified, simply a hydraulic friction engaging device or an engaging element). ) Consists of a wet multi-plate clutch and brake pressed by a hydraulic actuator, a band brake tightened by a hydraulic actuator, and the like.

By controlling the engagement and disengagement of these hydraulic friction engagement devices, as shown in the engagement operation table of FIG. 3, the driver operates the accelerator, the vehicle speed V, etc. Each gear stage of the stage is formed. In FIG. 3, "1st" to "8th" mean the first gear to the eighth gear as the forward gear, and "Rev" means the reverse gear as the reverse gear, and each gear. The gear ratio γ (= turbine shaft rotation speed Nt / transmission output gear rotation speed Nout) of the automatic transmission 22 corresponding to the above is the first planetary gear device 58, the second planetary gear device 60, and the third planetary gear device 62. It is appropriately determined by each gear ratio (= number of sun gear teeth / number of ring gear teeth). The transmission output gear rotation speed Nout corresponds to the vehicle speed V.

As shown in FIG. 4, the torque converter 20 is connected to the crank shaft 12a of the engine 12 so as to be able to transmit power, and has a pump impeller 20p corresponding to an input member arranged so as to rotate around the axis RC. It is provided with a turbine impeller 20t corresponding to an output member connected to the turbine shaft 30 so as to be able to transmit power. As is well known, the lockup clutch 32 has a mechanism for causing a difference rotation by sliding the first friction plate 38 and the second friction plate 40, and is controlled by the hydraulic control circuit 54. It is a hydraulic friction clutch that is frictionally engaged. As shown in FIG. 4, the torque converter 20 has a hydraulic oil supply port 20a to which the hydraulic oil output from the oil pump 33 is supplied and a hydraulic oil outflow port for discharging the hydraulic oil supplied from the hydraulic oil supply port 20a. A main oil chamber 20c having 20b is formed. Moreover, the main oil chamber 20c of the torque converter 20, a lock-up clutch 32, and a control oil chamber 20d of the lock-up engagement pressure _{P LUPON} is supplied, the front side oil the torque converter in pressure _{P TCIN} supplied A chamber 20e and a rear side oil chamber 20g which communicates with the front side oil chamber 20e and is filled with the hydraulic oil from the front side oil chamber 20e and causes the hydraulic oil to flow out from the hydraulic oil outflow port 20b are provided.

Lockup clutch 32, the torque output and lock-up on pressure _P LupON the control oil chamber 20d (kPa), the torque converter in pressure of the front side oil chamber 20e _P TCin (kPa) and from the working fluid outflow port 20b The transmission torque is based on the average value of the converter out pressure _{PTCout (kPa) ((PTCin} + _PTCout ) / 2), that is, the lockup engagement differential pressure Pc (= _PLupON − ( _PTCin + _{PTCout) / 2).} Be controlled. _{The above equation of} lockup engagement differential pressure (lockup differential pressure) Pc = P LoopON − ( _PTCin + _PTCout ) / 2 is an experimental equation determined in advance by experiments or the like, and the torque converter in pressure P. The average value (( _PTCin + _{PTCout ) / 2) of TCin} (kPa) and the torque converter out pressure _PTCout (kPa) is also called back pressure. Further, in the above equation, the torque converter in-pressure _PTCin and the torque converter out-pressure _PTCout are the engine rotation speed Ne (rpm), the turbine rotation speed Nt (rpm), and their difference rotation speeds (engine rotation speed-turbine rotation speed). ) Ns (rpm), second line hydraulic pressure Psec (kPa), hydraulic oil temperature Toil (° C.), engine 12 output torque Te (Nm) (hereinafter, engine output torque is referred to as engine torque) and the like. The torque converter out pressure _{PTCout changes} as the engine rotation speed Ne, turbine rotation speed Nt, hydraulic oil temperature Toil, etc. change and the centrifugal oil pressure in the rear oil chamber 20g of the torque converter 20 changes. do.

In the lockup clutch 32, the lockup engagement differential pressure Pc is controlled by the electronic control device (control device) 56 via the hydraulic control circuit 54, so that, for example, the lockup engagement differential pressure Pc is negative. In the so-called lock-up release state (lock-up off) in which the lock-up clutch 32 is released, the lock-up engagement differential pressure Pc is set to zero or more, and the lock-up clutch 32 starts half-engagement with slipping. That is, a lock-up slip state (slip state) that occurs from the start of inertia and a so-called lock-up state (lock-up on) in which the lock-up clutch 32 is completely engaged with the lock-up engagement differential pressure Pc set to the maximum value. It can be switched to any of the operating states. The above lock-up slip state control corresponds to flex lock-up control. Further, the complete lockup control corresponds to the control in which the lockup clutch 32 is completely engaged. Further, in the torque converter 20, even if the lockup clutch 32 is in the lockup state, the lockup slip state, or the lockup release state, the front side oil chamber 20e and the rear side oil chamber 20g are in the same chamber, that is, the front side oil chamber 20e. And the rear oil chamber 20g are always in communication with each other, and the lockup clutch 32 is suitably cooled by the hydraulic oil supplied from the hydraulic oil supply port 20a.

As shown in FIG. 4, the hydraulic control circuit 54 has a lockup control valve 64 and a first line whose pressure is regulated by a relief type first line pressure regulating valve 67 using the oil pressure generated from the oil pump 33 as the original pressure. _{It is provided with a linear solenoid valve SLU} that regulates the hydraulic PL to the lockup engagement pressure P SLU, and a modulator valve 66 that regulates the _{modulator hydraulic P MOD} to a constant value using the first line hydraulic PL as the original pressure. The hydraulic control circuit 54 includes linear solenoid valves SL1 to SL6 (see FIG. 1) that control the operation of each hydraulic actuator (not shown) of the hydraulic friction engagement device. In FIG. 4, the as source pressure of the linear solenoid valve SLU is the first line pressure PL has been used, may modulator pressure P _MOD is used in place of the first line pressure PL.

Further, as shown in FIG. 4, the lockup control valve 64 is a two-position switching valve of a type that can be switched from the OFF position to the ON position when the _{lockup engagement pressure PSLU exceeds a predetermined value, and is in the ON position.} , The first oil passage L1 is closed, the second oil passage L2 is connected to the third oil passage L3, the first oil passage L1 is connected to the discharge oil passage EX, and the fourth oil passage L4 is connected to the cooler 68. And, the fifth oil passage L5 is connected to the sixth oil passage L6. The first oil passage L1 is an oil passage through which the torque converter out pressure _PTCout output from the hydraulic oil outflow port 20b of the torque converter 20 is guided. The second oil passage L2 is an oil passage through which the lockup engagement pressure PSLU adjusted by the linear solenoid valve _SLU is guided. The third oil passage L3 is an oil passage through which the _{lockup-on pressure P LoopON} supplied to the control oil chamber 20d of the torque converter 20 is guided. The fourth oil passage L4 is an oil passage through which the second line oil pressure Psec adjusted by the second line pressure adjusting valve 69 is guided by using the oil relief from the first line pressure adjusting valve 67 as the original pressure. The fifth oil passage L5 is an oil passage modulator pressure P _MOD pressure regulated to a constant value by the modulator valve 66 is introduced. The sixth oil passage L6 is an oil passage through which the torque converter in-pressure _PTCin supplied to the front side oil chamber 20e of the torque converter 20 is guided.

Further, as shown in FIG. 4, the lockup control valve 64 connects the first oil passage L1 to the third oil passage L3, closes the second oil passage L2, and closes the first oil passage L1 at the OFF position. It connects to the cooler 68, connects the fourth oil passage L4 to the sixth oil passage L6, and closes the fifth oil passage L5. The lock-up control valve 64, a spring 64a for biasing the spool to the OFF position side, an oil chamber 64b that accepts a lock-up engagement pressure P _SLU for biasing the spool to the ON position side I have. In the lockup control valve 64, when the lockup engagement pressure _PSLU is smaller than a predetermined value set to be relatively small, the spool valve is held in the OFF position by the urging force of the spring 64a. Further, in the lockup control valve 64, when the lockup engagement pressure _PSLU is larger than the predetermined value, the spool valve is held in the ON position against the urging force of the spring 64a. In the lockup control valve 64 of FIG. 4, the solid line shows the flow path when the spool valve is in the ON position, and the broken line shows the flow path when the spool valve is in the OFF position.

The hydraulic control circuit 54 configured as described above switches the hydraulic pressure supplied from the lockup control valve 64 to the control oil chamber 20d and the front side oil chamber 20e in the torque converter 20 to operate the lockup clutch 32. The state can be switched. First, a case where the lockup clutch 32 is in the slip state or locked up on will be described. In the lock-up control valve 64, the electronic control device 56 the greater than the predetermined value has been locked up engagement pressure P _SLU by a command signal output from is supplied, the lock-up control valve 64 is switched to the ON position, the lock-up engagement pressure _{P SLU} is supplied to the control oil chamber 20d of the torque converter 20, the modulator pressure _{P MOD} supplied to the lock-up control valve 64 is supplied to the front side oil chamber 20e of the torque converter 20. That is, the lock-up engagement pressure _{P SLU} is supplied to the control oil chamber 20d as a lock-up on pressure _{P LupON,} modulator pressure _{P MOD} is supplied to the front side oil chamber 20e as a torque converter in pressure _{P TCIN.} When the lockup control valve 64 is switched to the ON position, the relationship between the size of the _{lockup on pressure P LoopON} , the torque converter in pressure _PTCin, and the torque converter out pressure _{PTCout is the lockup on pressure P. LoopON} > Torque converter in pressure P _TCin > Torque converter out pressure P _TC out. As a result, the lockup on pressure (engagement pressure) P _LoopON of the control oil chamber 20d of the torque converter 20 is adjusted by the linear solenoid valve SLU, so that the lockup engagement differential pressure (P _LoopON − ( _PTCin + P)) is adjusted. _TCout ) / 2) Pc is regulated, and the operating state of the lockup clutch 32 is switched in the range of the slip state or the lockup on (fully engaged).

Next, the case where the lockup clutch 32 is locked up and off will be described. In the lockup control valve 64, when the lockup engagement pressure _PSLU is smaller than the predetermined value, the lockup control valve 64 is switched to the OFF position by the urging force of the spring 64a, and the hydraulic oil outflow port of the torque converter 20 The torque converter out pressure _PTCout output from 20b is supplied to the control oil chamber 20d of the torque converter 20, and the second line hydraulic pressure Psec is supplied to the front oil chamber 20e of the torque converter 20. That is, the torque converter out pressure _PTCout is supplied to the control oil chamber 20d as the lockup on pressure _PLupON , and the second line hydraulic pressure Psec is supplied to the front side oil chamber 20e as the _{torque converter in pressure PTCin.} When the lockup control valve 64 is switched to the OFF position, _{the magnitude relationship between the lockup on pressure P LoopON} , the torque converter in pressure _PTCin, and the torque converter out pressure _PTCout is the torque converter in pressure. P _TCin > Torque converter out pressure P _TC out> Lockup on pressure P _Loop ON. As a result, the operating state of the lockup clutch 32 is switched to lockup / off.

FIG. 5 is an example of a time chart schematically showing the behavior of a piston (not shown) that engages the lockup clutch 32, and the lockup engagement differential pressure Pc is caused by the movement of the lockup clutch 32 during engagement. It is shown that it is affected by the fluctuation of back pressure ( _PTCin + _{PTCout) / 2 that occurs.} In FIG. 5, for simplification, the torque converter in-pressure _PTCin is represented by the back pressure, and the lockup engagement differential pressure Pc is shown as _{(PLupON- PTCin).} At the time of t0, the engagement of the lockup clutch 32 is started, and the indicated pressure (instructed hydraulic pressure) Slu of the linear solenoid valve SLU is set to P6. The oil pressure P6 is a first fill that temporarily increases the oil pressure, which is carried out to accelerate the engagement of the lockup clutch 32. At the time of t1, the difference between the lockup engagement differential pressure Pc, that is, the lockup on pressure P _LoopON and the torque converter pressure _PTCin reaches P1, and the lockup clutch 32 is started to engage. At the time of t2, the indicated pressure Slu of the linear solenoid valve SLU is reduced to P5, and the first fill is completed. Further, the torque converter pressure _PTCin has risen to P4. On the other hand, the lockup on pressure P _LoopON is raised to P5, and the lockup engagement differential pressure Pc is maintained at P1. At the time of t3, the influence of the first fill is almost not seen, and the value is almost constant until the time of t4. The lockup on pressure P _LoopON is P4, the torque converter pressure _PTCin is P3, and the lockup engagement differential pressure Pc. Indicates P1 respectively. In time t4, the engagement of the lock-up clutch 32 is completed, at time t5, lockup ON pressure _{P LupON} is the P5 is a command pressure Slu of the linear solenoid valve SLU, torque converter pressure _{P TCIN} is set P2 , And the lockup engagement differential pressure Pc indicates P3, respectively. As shown in FIG. 5, the lockup engagement differential pressure Pc is affected by the increase in back pressure during the engagement of the lockup clutch 32, and becomes a predetermined oil pressure after the lockup clutch 32 is engaged.

In the above torque converter 20, since the lockup clutch 32 is suitably cooled by the differential oil as described above, for example, the first friction plate 38 and the second friction plate 40 of the lockup clutch 32 are rubbed against each other. As a multi-plate consisting of plates, it is possible to expand the area of flex lockup control. However, by expanding the area of flex lockup control, the shift of the automatic transmission 22 is more likely to be performed during the flex lockup control of the lockup clutch 32, and during full lockup or flex lockup control. When the automatic transmission 22 is changed, it is more necessary to suppress the shock at the completion of the change, that is, to improve the drivability and to suppress the increase in fuel consumption due to the large slip of the lockup clutch. In the torque converter 20, the operating state of the lockup clutch 32 is controlled by the _{lockup on pressure P Loop} ON, the torque converter in pressure P _{TC in,} and the torque converter out pressure P _{TC out.} Not limited to. For example, even in a normal torque converter having a structure in which the operating state of the normal torque converter, that is, the lockup clutch 32 is controlled only by the differential _{pressure between the lockup on pressure P LoopON} and the lockup in pressure _PTCin. Similarly, there remains a need to improve fuel efficiency and reduce the shock generated during shifting.

FIG. 6 shows control for improving fuel efficiency and shock generated during shifting by bringing the difference rotation speed Ns of the lockup clutch 32 during upshift shifting, which has been conventionally implemented, closer to the target difference rotation speed Nst for hydraulic control. An example is shown. In this example, the target difference rotation speed Nst is set so that the difference rotation speed N12 is maintained from the time t1 to the time t2 and the difference rotation speed N15 is maintained from the time t2 to the time t3. Slu1, Slu2, and Slu3 are shown as the indicated pressures Slu of the linear solenoid valve SLU. The difference rotation speed Ns, which is the difference from the turbine rotation speed Nt, indicates Ns1 also shown by the solid line. The indicated pressure Slu1 is the indicated oil pressure P5 at which the lockup clutch 32 is completely locked up at the time of t0. ing. Along with this, a rotation difference N11 between the engine rotation speed Ne and the turbine rotation speed Nt is generated, and the lockup clutch 32 slips. At the time of t2, the indicated pressure Slu of the solenoid valve SLU decreases to P1, and after the time of t2, Ns1, which is the difference between the engine rotation speed Ne1 and the turbine rotation speed Nt, approaches the target difference rotation Nst. After t3, the indicated pressure Slu of the solenoid valve SLU is increasing toward complete lockup. The indicated pressure Slu3 is the indicated oil pressure P2 from the time t0 to the time t2, and the difference rotation speed Ns indicates N13 until the time t2. From the time point t2 to the time point t3, the indicated oil pressure P1 is the same as that of Slu1, and the differential rotation Ns3 is approaching the target differential rotation Nst. After the time t3, the oil pressure for maintaining the predetermined differential rotation indicated by the dotted line is set. The indicated pressure Slu2 shows an intermediate state between Slu1 and Slu3. In the actual control of the lockup clutch, the differential rotation speed Ns is set by selecting an appropriate instruction pressure Slu according to the state of the differential rotation speed Ns of the lockup clutch 32 before the start of shifting of the automatic transmission 22. Control is performed to bring the target difference rotation Nst closer to the predetermined setting. In the above control, for example, there is a difference in the driving mode such as a driving mode, that is, a sports mode, a normal mode, and an eco mode, a difference in the shifting direction between the downshift and the upshift, and a multiple shifting in which the gear shifting extends to a plurality of gears. Since the difference in the gear ratio step is not controlled separately, it is necessary to improve the fuel efficiency and the reduction of the shock generated at the time of shifting.

Returning to FIG. 1, the vehicle 10 includes an electronic control device 90 including a control device that controls each part involved in traveling. The electronic control device 56 includes, for example, a so-called microcomputer provided with a CPU, a RAM, a ROM, an input / output interface, and the like, and the CPU follows a program stored in the ROM in advance while using the temporary storage function of the RAM. Various controls of the vehicle 10 are executed by performing signal processing.

The electronic control device 56 is supplied with outputs from operation switches included in the vehicle 10 and various input signals detected by various sensors. For example, the operation mode selection signal SWON output based on the operation of the driver's operation mode selection switch 46, the signal indicating the throttle valve opening degree θth (%) detected by the throttle valve opening degree sensor 70, and the vehicle speed sensor 72. A signal indicating the detected vehicle speed V (km / h), a signal indicating the oil temperature Tool (° C.) of the hydraulic oil detected by the oil temperature sensor 74, and an operation amount of the accelerator pedal detected by the accelerator opening sensor 76. The signal Acc (%) to be represented, the engine rotation speed Ne (rpm) detected by the engine rotation speed sensor 78, the turbine rotation speed Nt (rpm) detected by the turbine rotation speed sensor 80, and the like are input to the electronic control device 56. NS. Further, from the electronic control device 56, a shift instruction pressure Sat for hydraulic control related to the shift of the automatic transmission 22, a throttle (not shown) related to the control of the engine 12, ignition timing of the ignition coil, fuel injection amount, valve timing, etc. The instruction signal Se, the lockup instruction pressure (instruction pressure) Slu for switching the operating state of the lockup clutch 32, and the like are output. Incidentally, the lock-up command pressure Slu is a command signal for driving the linear solenoid valve SLU for pressurizing regulating the lockup engagement pressure P _SLU, is output to the linear solenoid valve SLU of the hydraulic control circuit 54.

The operation mode selection switch 46, which is an operation switch included in the vehicle 10, is compared with a predetermined normal mode for driving so as to be able to drive in a fuel-efficient state while drawing out power performance, and a comparison with the normal mode. A predetermined sports mode (that is, power mode) for driving so that driving can be performed in a state where power performance is prioritized over fuel efficiency, and fuel efficiency is prioritized over power performance compared to the normal mode. It has a predetermined eco-mode for driving so that it can be driven in the state of being in the normal mode, and it is possible to switch the driving mode between the normal mode, the sports mode and the eco-mode. The operation mode selection switch 46 is arranged near, for example, the driver's seat. The operation mode selection switch 46 is, for example, a seesaw type switch that enables the driver to select the vehicle running in the operation mode desired by the driver, and the sports mode switch 42 or the eco mode switch 44 is pressed by the driver. By doing so, the sport mode or the eco mode is selected (set). If neither the sports mode switch 42 nor the eco mode switch 44 is pressed, the normal mode is selected (set).

The electronic control device 56 shown in FIG. 1 includes a speed change means 100 and a slip control means 102 corresponding to the slip control device as a main part of the control function. The shifting means 100 includes a shifting determining means 104 surrounded by a broken line, a traveling mode determining means 106, a shifting controlling means 108, a shifting gear stage determining means 110, and a target shifting time calculating means 112. Further, the slip control means 102 includes a lockup clutch determination means 114 surrounded by a dotted line, a lockup clutch control value determination means 116, and a lockup clutch control means 118.

When the operating state of the vehicle falls within a predetermined control region, for example, the lockup clutch 32 completely engages the lockup clutch 32 to engage the pump impeller 20P and the turbine impeller 20t. It is determined to execute the complete lockup control for the direct connection state, the flex lockup control for the pump impeller 20P and the turbine impeller 20t to be semi-directly connected by half-engaging (slip) the lockup clutch 32. The operating area in which the implementation of the complete lockup control, the flex lockup control, or the like is determined is set in advance as, for example, the relationship between the accelerator opening and the vehicle speed. When the lockup clutch determining means 114 determines the execution of the complete lockup control or the flex lockup control, the lockup clutch determining means 114 issues an instruction to execute the complete lockup control or the flex lockup control to the lockup clutch control means 118, and determines the shift. The means 104 is informed that the complete lockup control or the flex lockup control is being executed to the transmission means 100. The lockup clutch control means 118 controls the lockup clutch 32 based on the instruction of the lockup clutch determination means 114.

The shift determination means 104 is actually performing the complete lockup control or the flex lockup control, and the relationship (map, shift diagram) stored in advance with, for example, the vehicle speed V and the accelerator opening Acc as variables. It is determined that the shift control is started based on the vehicle speed V and the accelerator opening degree Acc. When it is determined that the automatic transmission 22 starts shifting while the complete lockup control or the flex lockup control is being executed, the transmission gear stage determination means 110 determines that the determined shift is from the normal upshift, that is, the N speed ( It is determined whether the gear is a shift to an adjacent gear to the N + 1) gear, or a normal downshift, that is, a shift from the N gear to the adjacent gear to the (N-1) gear. Shifts other than the normal upshift and the normal downshift include, for example, multiple shifts in which a plurality of gears are simultaneously performed.

The speed change gear stage determining means 110 further determines what the speed change stage after the shift is switched by the shift. In the case of multiple shifts, it is determined whether the shift includes the shift stage after the shift and the shift stage which is switched by the shift. The traveling mode determining means 106 determines whether the selected traveling mode is a sports mode, a normal mode, or an eco mode.

The target shift time calculation means 112 includes a traveling mode including a sports mode, a normal mode, an eco mode, and a shift type, such as a normal upshift, a normal downshift, and other shift directions and shift steps such as multiple shifts. The shift time of the automatic transmission 22, that is, the target shift time tt is calculated based on the shift stages before and after the shift that reflect the magnitude of. The target shift time tt is a map that is preset and stored in accordance with the range of change in the gear ratio that is switched by shifting, that is, the range of change in engine rotation speed Ne due to shifting, and the driving mode based on the driver's selection. It is decided based on. The target shift time tt is set in the sport mode, for example, as a target shift time tt for a shorter time than running in the normal mode, giving priority to a quick acceleration response, that is, a direct feeling. In the normal mode, for example, the setting is such that suppression of shift shock and acceleration response are well balanced. Further, in the control of the target shift time tt, the control is performed by adjusting the torque phase time, the inertia phase time, the target rotation speed, and the like.

The lockup clutch control value determining means 116 supplies the control value of the lockup clutch 32 corresponding to the calculated target shift time tt, that is, the lockup clutch 32 for achieving the target difference rotation speed Nst or the target difference rotation Nst. The indicated pressure Slu or the like of the differential oil to be operated is determined based on a predetermined relationship (map). It should be noted that these control values do not have to be particularly constant, and the set values may be changed, for example, stepwise with the elapsed time from the start of the control values of the lockup clutch 32. The above target shift time tt is calculated based on the traveling mode and the type of shifting to be executed, and the target shifting time tt is preset so as to reflect these traveling modes and the type of shifting to be executed. ing. Further, the control value determined by the lockup clutch control value determining means 116 is also set to reflect these traveling modes and the type of shifting to be executed. The lockup clutch control means 118 controls the lockup clutch 32 based on the calculated control value. The shift control of the automatic transmission 22 is executed in parallel with the control of the lockup clutch 32, and the shift control means 108 completes the shift control of the automatic transmission 22. In the shift control of the automatic transmission 22, for example, by correcting the inertia phase time after the start of the inertia phase, it is possible to further reduce the shift shock at the end of the inertia phase.

FIG. 7 is a flowchart illustrating slip control of the lockup clutch 32 during shifting of the automatic transmission 22 by the electronic control device 56. In step S10 corresponding to the functions of the lockup clutch determining means 114 and the lockup clutch controlling means 118 (hereinafter, the step is omitted), it is determined that the lockup clutch 32 is in a completely locked up state or the flex lockup control is executed. Full lockup condition or flex lockup control is implemented. If the S10 determination is denied, the determination from S10 is repeated. When the S10 determination is affirmed, that is, when complete lockup or flex lockup control is being executed, it is determined whether or not the automatic transmission 22 has started shifting in S20 corresponding to the function of the shift determination means 104. Will be done. If the determination in S20 is denied, the determination from S10 is repeated. If the determination in S20 is affirmed, it is determined in S30 corresponding to the function of the transmission gear stage determination means 110 whether or not it is a normal upshift. If this determination is denied, in S40 corresponding to the function of the transmission gear stage determination means 110, it is determined whether or not the downshift is normal. If this S40 determination is denied, in S50 corresponding to the function of the shift gear stage determination means 110, it is determined that the shift is another shift, for example, multiple shifts.

When the determination in S30 is affirmed and it is determined that the shift of the automatic transmission 22 is an upshift to an adjacent shift stage, in S60 corresponding to the function of the shift gear stage determination means 110, after the shift is switched by the shift. Gear stage is determined. Further, in S90 corresponding to the function of the traveling mode determining means 106, it is determined which of the sports mode, the normal mode, the eco mode, and the like is the selected traveling mode. The target shift time tt is determined in S120 corresponding to the function of the target shift time calculation means 112. In S150 corresponding to the functions of the lockup clutch control value determining means 116 and the lockup clutch controlling means 118, the control value of the lockup clutch 32, that is, the target difference rotation Nst is determined and controlled so as to approach the target difference rotation Nst. Is done. As the control value, the indicated pressure Slu of the differential oil supplied to the lockup clutch 32 for achieving the target difference rotation Nst may be used instead of the target difference rotation Nst. In S160 corresponding to the function of the shift control means 108, the shift of the automatic transmission 22 is continued, and then the shift is completed.

Steps S60 and S90 performed when the determination of S40 is affirmed, that is, when the shift of the automatic transmission 22 is determined to be a normal downshift, and when it is determined to be a normal upshift. After the transmission gear stage determination in S70, the traveling mode determination in S100, and the target shift time in S130 are determined in the same manner as in S120, the target difference rotation or the oil pressure determination of the lockup control in S150 described above is performed. The control is executed based on the value, and the shift of the automatic transmission 22 in S160 is executed and completed. If the determination in S40 is denied, it is determined in S50 corresponding to the function of the transmission gear stage determination means 110 that it is another shift, for example, multiple shifts. After that, the shift gear stage was determined in S80, the traveling mode was determined in S110, and the target shift time was determined in S140, as in steps S60, S90, and S120, which are performed when it is determined to be a normal upshift. After that, the target difference rotation or the oil pressure of the lockup control in S150 is determined and the control is executed based on the value, and the shift of the automatic transmission 22 in S160 is executed and completed.

According to this embodiment, when the automatic transmission 22 starts shifting during the complete lockup control or the flex lockup control of the lockup clutch 32, the shift stages before and after the shift are switched by the shift. The target shift time tt required for shifting is calculated based on at least one of the vehicle and the traveling mode of the vehicle, and the target difference rotation Nst between the pump impeller 20p and the turbine impeller 20t of the lockup clutch 32 is calculated based on the target shift time tt. By setting, it is possible to reflect the difference in demand for slip control between the driving mode such as sports mode, normal mode, and eco mode and the difference in shifting such as upshift, downshift, and multiple shift. By controlling the shift of the automatic transmission 22 and the lockup flex control of the lockup clutch 32 in a coordinated manner, it is possible to appropriately achieve both improvement of drivability and improvement of fuel efficiency by reducing the shock at the completion of the shift. can.

Although the examples of the present invention have been described in detail with reference to the drawings, the present invention also applies to other aspects.

The target time tt for shifting was set based on the shift stage in which the traveling mode and the automatic transmission 22 can be switched. For example, the engine torque is adjusted by adjusting the ignition retard of the engine, that is, the ignition timing of the engine 12. When it is difficult to control, for example, when the cooling water temperature drops, the target time tt for shifting may be adjusted longer than usual. That is, the target time tt of the shift is not only based on the traveling mode and the shift stage to be switched, but can be incorporated if any difference can be obtained by adjusting the target time tt of the shift.

Further, in the automatic transmission 22 of the above-described embodiment, the 8-speed gear stage is used, but the gear stage is not particularly limited to the 8-speed gear, and the number of gear stages is lower than this, or the number of gear stages is higher than this, for example, the 10-speed gear. The number of gears of may be used, or a continuously variable transmission may be used.

It should be noted that the above is only one embodiment, and the present invention can be implemented in a mode in which various modifications and improvements are made based on the knowledge of those skilled in the art.

10: Vehicle 12: Engine 22: Automatic transmission 20: Torque converter 20p: Pump impeller (input member)
20t: Turbine impeller (output member)
32: Lockup clutch 56: Electronic control device (control device)
102: Slip control means (slip control device)
tt: Target shift time (shift time)
Nst: Target differential rotation

Claims (1)

An engine, an automatic transmission, a torque converter provided between the engine and the automatic transmission, a lockup clutch that directly connects an input member of the torque converter and an output member of the torque converter, and the lock. A vehicle control device including a lock-up clutch slip control device that controls the difference rotation between the input member and the output member of the up-clutch.
When the shift of the automatic transmission is started during the complete lockup control or the flex lockup control of the lockup clutch, the shift stages before and after the shift and the traveling mode of the vehicle, which are switched by the shift, The vehicle control device is characterized in that the shift time required for the shift is calculated based on the above, and the longer the shift time is, the larger the target difference rotation between the input member and the output member of the lockup clutch is set.

Images