JP6773570B2 - Control device for vehicle power transmission device - Google Patents

Description

The present invention relates to a vehicle power transmission device in which a lockup clutch is provided between a prime mover and an automatic transmission, and in particular, when shifting the automatic transmission, the lockup clutch is engaged in a predetermined slip state. It relates to the improvement of flex lockup control.

A vehicle power transmission device in which a friction-engagement type lockup clutch is provided between a prime mover and an automatic transmission is known. The device described in Patent Document 1 is an example thereof, in which a lockup clutch is provided in the fluid type transmission device, and when it is determined that the vehicle is running in sports, a deceleration determination threshold value for releasing the lockup is determined as compared with the case where the driving is not in sports. Is getting bigger. Further, in Patent Document 2, a flex lockup control is performed in which the lockup clutch is slip-engaged during deceleration running, and a lockup clutch is performed before the end of shifting in order to suppress a shift shock during shifting during deceleration running. A technique for lowering the engagement pressure (lock-up engagement pressure) has been proposed.

JP-A-2009-97603 Japanese Unexamined Patent Publication No. 7-10339

By the way, in general, the shift control is different depending on the type of shift, the traveling mode, etc., and the start time of the inertia phase and the rate of change of the input rotation speed in the inertia phase are different, but the conventional flex lockup control at the time of shift is the shift. Since there is no coordination with the control, there is a possibility that the drive (shift shock, acceleration response, etc.) may deteriorate or the fuel consumption may be impaired depending on the content of the shift control. In particular, by adopting a multi-plate type lockup clutch, lockup control becomes possible even at high torque and high rotation, and the lockup control area including the slip area is expanded, so that the above problem becomes remarkable.

The present invention has been made in the background of the above circumstances, and an object of the present invention is to ensure that flex lockup control at the time of shifting is appropriately performed according to the content of shifting control.

In order to achieve such an object, the present invention is provided in a vehicle power transmission device provided with a friction-engagement type lockup clutch between a prime mover and an automatic transmission, and the lock is provided when the automatic transmission shifts. In a control device of a power transmission device for a vehicle having a shift flex lockup control unit that executes a shift flex lockup control that controls a lockup engagement pressure so that the up clutch is engaged in a predetermined slip state. (a) when a downshift of the automatic transmission, a predetermined target time associated with the transmission is set based on the vehicle information Rutotomoni, the target time goals Suberidashi time until the inertia phase starts at the start of the shift control or It is the target shift time from the start of the shift control to the end of the shift control, and the shift control of the automatic transmission is performed according to the target shift time, while (b) the flex lockup control unit at the time of the shift is the automatic transmission of the automatic transmission. When the lockup engagement pressure is controlled so that the lockup clutch is in the predetermined slip state during the downshift, the lockup engagement pressure is applied at an initial stage before the inertia phase of the downshift starts. When the target time is short, the lockup clutch is engaged in the initial stage so that the pressure reducing width of the lockup engagement pressure in the initial stage is larger than that in the case where the target time is short. It is characterized by being provided with a shift coordination unit that adjusts the decompression width of the combined pressure .
Note that the slip state is a slip amount of the lock-up clutch (differential rotation).

In such a control device for a vehicle power transmission device, the lockup engagement pressure of the flex lockup control during shifting is reduced at the initial stage of downshifting, so that the slip amount is quickly increased and the inertia phase The start is quicker, the downshift is executed quickly, and the driving performance such as acceleration performance is improved. In particular, since the decompression range of the lockup engagement pressure is adjusted according to the target time used for shift control, even if the target time differs depending on the type of shift, the traveling mode, etc., the target time is adjusted. when shifting Te flex lock-up control is to be properly performed, thereby improving the Dorabi Li.

It is a figure explaining the schematic structure of the drive system of the vehicle to which this invention is applied, and 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 sectional drawing of the torque converter of FIG. It is an engagement operation table explaining a plurality of gear stages established by the automatic transmission of FIG. 2, and a hydraulic friction engagement device which establishes each gear stage. FIG. 5 is a hydraulic circuit diagram illustrating an example of a hydraulic control circuit having a linear solenoid valve or the like for controlling the operation of a lockup clutch provided in the torque converter of FIG. It is a flowchart which specifically explains the shift-shift flex lock-up control executed by the shift-shift flex lock-up control unit of the electronic control device of FIG. It is a figure explaining an example of the data map used when calculating the drain correction amount in step S7 of FIG. This is an example of a time chart for explaining changes in the operating state of each part when flex lockup control during shifting is performed according to the flowchart of FIG. It is a figure explaining another embodiment of this invention, and is an example of the time chart in the case where the flex lockup control at the time of shifting is performed in the inertia phase at the time of upshift. This is an example of a time chart when flex lockup control is performed during shifting in the inertia phase during downshifting.

As the prime mover that is the drive source of the vehicle, for example, an engine that is an internal combustion engine is used, but an electric motor or a combination of an electric motor and an engine may be used. As the automatic transmission, a stepped transmission such as a planetary gear type or a parallel shaft type, or a continuously variable transmission such as a belt type is used. The stepped transmission is configured so that, for example, a plurality of gear stages having different gear ratios are established depending on the engagement disengagement state of the plurality of hydraulic friction engaging devices. As the lockup clutch, a single-plate or multi-plate hydraulic friction clutch or an electromagnetic friction clutch can be used. For example, the lockup clutch is provided incidentally to a fluid transmission device such as a torque converter, but is provided independently as a start clutch. You can also do it.

Gear shifting flex lock-up control unit may performs a shifting time flex lock-up control over the entire speed change control, but may be only performed during shifting flex lock-up control part. Lock slip state ie the slip amount of click-up clutch (differential rotation) in order to correspond to the lock-up engagement pressure, transmission coordination unit is adjusted according to that of Russia Kkuappu engagement pressure itself to the target time. The lockup engagement pressure is controlled by directly controlling the lockup engagement pressure with a linear solenoid valve or the like, as well as the lockup on pressure acting in the direction of frictionally engaging the lockup clutch and the direction of releasing the lockup clutch. The lock-up-off pressure acting on the clutch may be controlled, and the lock-up-on pressure and the lock-up-off pressure may be adjusted according to the target time.

Target time related to gear shifting, for example, the target Suberidashi time or until the inertia phase starts at the start of the shift control, including during target shift to shift end from the start of shift control. These target times are, for example, the type of shifting (upshift, downshift, shifting from which gear to which gear), power ON (driving state), power OFF (driven state), running mode (sports mode). , Normal mode, eco mode, etc.), ATF oil temperature, transmission input torque, vehicle speed, etc. are set based on vehicle information. That is, the target time is set by a map or the like with one or more of the above vehicle information as parameters (variables) in consideration of driving speed such as shift shock and acceleration response, fuel efficiency, etc., and is based on the actual vehicle information. The target time can be obtained from the map or the like.

The shift lockup control unit includes, for example, an initial pressure reducing unit that reduces the lockup engagement pressure (drain correction) at the initial stage of downshift shift control. That is, in the case of downshift, the lockup engagement pressure is reduced as a basic control in order to quickly increase the input rotation speed, but the movement of the piston that presses the friction material is hindered by the flow resistance due to the viscosity of the hydraulic oil. Since the decrease in the actual lockup engagement pressure (transmission torque) is delayed due to such factors, the response delay can be suppressed by reducing the lockup engagement pressure by the initial decompression unit. In that case, the shift coordination unit adjusts the decompression width (drain correction amount) of the lockup engagement pressure according to the target shift time and the like . When the lockup engagement pressure is changed to the boosting side at the time of upshifting or the like, a response delay may occur in the same manner. Therefore, an initial boosting portion can be provided as needed, and the target shift time can be set. It is desirable to adjust the pressure increase width according to the above.

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 drive system 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. The vehicle 10 includes an engine 12, a drive wheel 14, and a vehicle power transmission device 16 (hereinafter, referred to as a power transmission device 16) provided in a power transmission path between the engine 12 and the drive wheel 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. It includes a differential gear device (differential gear) 26 in which a ring gear 26a is meshed with the output gear 24, and a pair of axles 28 and the like connected to the differential gear device 26. In the power transmission device 16, the power output from the engine 12 is sequentially transmitted 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. The engine 12 is a power source of the vehicle 10, that is, a prime mover, for example, an internal combustion engine such as a gasoline engine or a diesel engine, and the torque converter 20 is a fluid transmission device.

FIG. 2 is a skeleton diagram illustrating an example of the torque converter 20 and the automatic transmission 22, and FIG. 3 is a cross-sectional view of the torque converter 20. The torque converter 20 and the automatic transmission 22 are configured substantially symmetrically with respect to the axis RC of the transmission input shaft 30 which is an input rotating member of the automatic transmission 22, and in FIG. 2, below the axis RC. Half is omitted. Further, in FIG. 3, a portion below the transmission input shaft 30 is omitted. The torque converter 20 has a front cover 34 and a rear cover 35 welded to each other, and a plurality of pump blades 20f fixed to the inside of the rear cover 35, and is connected to the crankshaft 12a of the engine 12 so as to be able to transmit power. A pump impeller 20p arranged to rotate around the axis RC and a pump impeller 20p arranged inside the rear cover 35 so as to face the rear cover 35 and connected to a transmission input shaft (turbine shaft) 30 so as to be able to transmit power. It is equipped with a turbine impeller 20t. The torque converter 20 is a lockup clutch 32 capable of directly connecting the pump impeller 20p and the turbine impeller 20t by supplying the lockup control pressure Pslu (see FIG. 5) into the control oil chamber 20d. It has. That is, the torque converter 20 functions as a fluid transmission device for a vehicle with a lockup clutch provided in the power transmission path between the engine 12 and the automatic transmission 22. Further, the power transmission device 16 is provided with a mechanical oil pump 33 connected to the pump impeller 20p so as to be able to transmit power. The oil pump 33 is rotationally driven by the engine 12 to control the shift of the automatic transmission 22, engage the lockup clutch 32, and supply hydraulic oil to each part of the power transmission path of the power transmission device 16. Generates (discharges) hydraulic pressure for the purpose of pumping.

The lockup clutch 32 is a hydraulic multi-plate friction clutch (wet multi-plate clutch), and the lockup clutch 32 has a front cover 34 integrally connected to a pump impeller 20p as shown in FIG. The first annular member 36 fixed by welding to the outer peripheral spline teeth 36a formed on the outer periphery of the first annular member 36 are engaged with each other so as to be relatively non-rotatable around the axial center RC and movable in the axial center RC direction. A plurality of (three in FIG. 3) annular first friction plates (friction materials) 38 are provided. The lockup clutch 32 also has a second annular member 42 connected to the transmission input shaft 30 and the turbine impeller 20t via a damper device 40 provided in the torque converter 20 so as to be able to transmit power, and a second annular member 42. It is engaged with the inner peripheral spline teeth 42a formed on the inner circumference of the member 42 so as to be relatively non-rotatable around the axial center RC and movable in the axial center RC direction, and is arranged between the plurality of first friction plates 38. A plurality of (two in FIG. 3) annular second friction plates (friction materials) 44 are provided. The lockup clutch 32 is further attached to a hub member 46 which is fixed to the inner peripheral portion 34a of the front cover 34 and rotatably supports the end portion of the transmission input shaft 30 on the front cover 34 side around the axial center RC. An annular pressing member (piston) 48 that is movably supported in the RC direction and faces the front cover 34, and a hub member 46 that is supported in a fixed position and is supported on the opposite side of the pressing member 48 from the front cover 34 side. The annular fixing member 50 and the pressing member 48 arranged so as to face the 48 are urged toward the fixing member 50 in the axial RC direction, that is, the pressing member 48 is urged toward the fixing member 50 in the axial RC direction. And a return spring 52 that urges the second friction plate 44 in a direction away from the second friction plate 44.

As shown in FIG. 3, the torque converter 20 is provided with a main oil chamber (torque converter oil chamber) 20c in the front cover 34 and the rear cover 35. The hydraulic oil output from the oil pump 33 is supplied to the main oil chamber 20c from the hydraulic oil supply port 20a, and the hydraulic oil in the main oil chamber 20c is discharged from the hydraulic oil outflow port 20b. (See the thick dashed arrow in FIG. 5). In the main oil chamber 20c of the torque converter 20, a pressure for engaging the lockup clutch 32 and the lockup clutch 32, that is, pressing the first friction material 38 and the second friction material 44 of the lockup clutch 32. The control oil chamber 20d to which the lockup control pressure Pslu for urging the member 48 toward the front cover 34 side and the pressing member 48 for releasing the lockup clutch 32, that is, the pressing member 48 is opposite to the front cover 34 side. The front side oil chamber 20e to which the second line hydraulic PL2 (see FIG. 5) for urging to the side is supplied, and the front side oil chamber 20e is communicated with the hydraulic oil from the front side oil chamber 20e. A rear oil chamber 20g is provided to allow the hydraulic oil to flow out from the hydraulic oil outflow port 20b. The control oil chamber 20d is an oil-tight space formed between the pressing member 48 and the fixing member 50, and the front side oil chamber 20e is formed between the pressing member 48 and the front cover 34. The rear side oil chamber 20g is a space in the main oil chamber 20c excluding the control oil chamber 20d and the front side oil chamber 20e.

As shown in FIG. 3, in the torque converter 20, for example, the hydraulic pressure of the hydraulic oil supplied to the control oil chamber 20d, that is, the lockup-on pressure Plupon is relatively large (the hydraulic pressure of the front oil chamber 20e, that is, the torque converter in-pressure Ptcin). When the pressing member 48 is urged and moved to the front cover 34 side as shown by the one-point chain line, the pressing member 48 presses the first friction plate 38 and the second friction plate 44. The pump impeller 20p connected to the first annular member 36 and the turbine impeller 20t connected to the second annular member 42 are integrally rotated. That is, in the torque converter 20, when the lockup clutch 32 is engaged, the pump impeller 20p and the turbine impeller 20t are directly connected. Further, for example, the lockup-on pressure Plupon of the control oil chamber 20d becomes relatively small (the torque converter in pressure Ptcin of the front side oil chamber 20e becomes relatively large), so that the pressing member 48 has the first friction as shown by the solid line. When moved to a position away from the plate 38, the relative rotation of the pump impeller 20p connected to the first annular member 36 and the turbine impeller 20t connected to the second annular member 42 is allowed. That is, when the lockup clutch 32 is released, the torque converter 20 is released from the direct connection state between the pump impeller 20p and the turbine impeller 20t, and relative rotation is allowed.

The transmission torque of the lockup clutch 32 is controlled based on, for example, the lockup differential pressure ΔPlup represented by the following equation (1). This lockup differential pressure ΔPlop is a torque converter which is the hydraulic pressure of the lockup on pressure Plupon in the control oil chamber 20d, the torque converter in-pressure Ptcin in the front side oil chamber 20e, and the hydraulic oil flowing out from the hydraulic oil outflow port 20b. Out pressure This is the differential pressure from the lockup-off pressure, which is the average value of Ptcout [(Ptcin + Ptcout) / 2]. Equation (1) is an empirical formula determined in advance by experiments or the like, and is appropriately determined according to the structure or the like of the torque converter 20. Further, in the equation (1), the torque converter in-pressure Ptcin and the torque converter out-pressure Ptcout are the engine speed Ne, the turbine speed (speed of the transmission input shaft 30) Nt, and their difference rotation ΔN (= Ne−). It changes depending on Nt), the second line hydraulic pressure PL2, ATF oil temperature (hydraulic oil temperature) Turbine, engine torque Te, and the like. The torque converter out pressure Ptcout also changes when the engine speed Ne, turbine speed Nt, ATF oil temperature Tool, etc. change and the centrifugal oil pressure in the rear oil chamber 20 g of the torque converter 20 changes. .. The lockup differential pressure ΔPlup corresponds to the lockup engagement pressure corresponding to the transmission torque.
ΔPlop = Plupon- (Ptcin + Ptcout) / 2 ... (1)

In the lockup clutch 32, the lockup differential pressure ΔPlup is controlled by the electronic control device 56 via the hydraulic control circuit 54, so that, for example, the lockup differential pressure ΔPlup becomes negative and the lockup clutch 32 is released. The so-called lock-up release state (lock-up off) and the so-called lock-up slip state (slip state) in which the lock-up differential pressure ΔPlup is set to zero or more and the lock-up clutch 32 is half-engaged with slippage. The differential pressure ΔPlup is set to the maximum value, and the lockup clutch 32 is switched to one of the so-called lockup states (lockup on) in which the lockup clutch 32 is completely engaged. That is, in the case of the relationship of Ptcin> Ptcout> Plupon, the lockup is released, and in the case of the relationship of Plupon> Ptcin> Plupon, the lockup state or the lockup slip state is obtained according to the lockup differential pressure ΔPlop. 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 constantly cooled by the hydraulic oil flowing from the hydraulic oil supply port 20a to the rear oil chamber 20g.

The automatic transmission 22 shown in FIG. 2 constitutes a part of the power transmission path from the engine 12 to the drive wheels 14, and is a plurality of first clutches C1 to fourth clutches C4, which are hydraulic friction engagement devices. A plurality of gears having different gear ratios γ by selectively engaging or disengaging the 1st brake B1, the 2nd brake B2 (hereinafter, simply referred to as a hydraulic friction engaging device CB unless otherwise specified) and the one-way clutch F1. It is a planetary gear type multi-speed transmission that functions as a stepped automatic transmission in which a stage (shift stage) is formed. 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. The rotation of the transmission input shaft 30 which is located (on the axis RC) and is an input rotation member is changed and output from the transmission output gear 24.

The first planetary gear device 58 includes a first sun gear S1, a first ring gear R1 arranged concentrically with the first sun gear S1, and a pair of gear pairs that mesh with the first sun gear S1 and the first ring gear R1. It has one pinion gear P1 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, a second ring gear R2 arranged concentrically with the second sun gear S2, a second pinion gear P2 that meshes with the second sun gear S2 and the second ring gear R2, and a second pinion gear P2 thereof. It has a second carrier CA2 that supports the two pinion gears P2 so that they can rotate and revolve. The third planetary gear device 62 includes a third sun gear S3, a third ring gear R3 arranged concentrically with the third sun gear S3, and a pair of gears that mesh with the third sun gear S3 and the third ring gear R3. It has a third pinion gear P3 and a third carrier CA3 that supports the third pinion gear P3 so that it can rotate and revolve.

Linear solenoid valves SL1 to SL6 (see FIG. 1) are arranged corresponding to each hydraulic actuator of the hydraulic friction engagement device CB, and the linear solenoid valve is arranged according to the shift control signal Sat output from the electronic control device 56. The SL1 to SL6 are controlled, and the hydraulic friction engagement device CB is individually controlled to release the engagement. Therefore, as shown in the engagement operation table of FIG. 4, the driver operates the accelerator, the vehicle speed V, and the like. Each gear stage of 8th forward speed and 1st reverse speed is formed. “1st” to “8th” in FIG. 4 mean the first gear to the eighth gear as the forward gear, and “Rev” means the reverse gear. In the forward gear stage, the gear ratio γ (= transmission input shaft rotation speed Nin / transmission output gear rotation speed Nout) is changed from the first speed gear stage “1st” on the low speed side to the eighth gear stage “1st” on the high speed side. It gradually becomes smaller toward "8th".

FIG. 5 is a hydraulic circuit diagram illustrating an example of the hydraulic control circuit 54 relating to lockup clutch control. The hydraulic pressure control circuit 54 locks up the lockup control valve 64 and the first line hydraulic pressure PL1 regulated by the relief type first line pressure adjusting valve 67 using the hydraulic pressure generated from the oil pump 33 as the original pressure. It includes a linear solenoid valve SLU that regulates the pressure to Pslu, and a modulator valve 66 that regulates the pressure to a constant modulator hydraulic pressure Pmod with the first line hydraulic pressure PL1 as the original pressure. The hydraulic control circuit 54 is provided with an oil passage for supplying the first line hydraulic pressure PL1 to the linear solenoid valves SL1 to SL6. In FIG. 5, the first line hydraulic pressure PL1 is used as the main pressure of the linear solenoid valve SLU, but the modulator hydraulic pressure Pmod may be used instead of the first line hydraulic pressure PL1.

The lockup control valve 64 is a two-position switching valve that switches from the OFF position to the ON position when ON hydraulic pressure is supplied from the ON / OFF solenoid valve SL. When the lockup control valve 64 is switched to the ON position, as shown by the solid line in FIG. 5, the first oil passage L1 is closed, the second oil passage L2 is connected to the third oil passage L3, and the first oil passage is connected. L1 is connected to the discharge oil passage EX, the fourth oil passage L4 is connected to the oil 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 hydraulic oil of 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 hydraulic oil of the lockup control pressure Pslu adjusted by the linear solenoid valve SLU is guided. The third oil passage L3 is an oil passage through which the hydraulic oil of the lockup-on pressure Plupon 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 hydraulic oil of the second line hydraulic pressure PL2 regulated by the second line pressure regulating valve 69 is guided by using the hydraulic pressure relieved from the first line pressure regulating valve 67 as the original pressure. is there. The fifth oil passage L5 is an oil passage through which the hydraulic oil of the modulator hydraulic pressure Pmod whose pressure is adjusted to a constant value by the modulator valve 66 is guided. The sixth oil passage L6 is an oil passage through which the hydraulic oil of the torque converter in-pressure Ptcin supplied to the front side oil chamber 20e of the torque converter 20 is guided.

When the lockup control valve 64 is switched to the OFF position, the first oil passage L1 is connected to the third oil passage L3, the second oil passage L2 is closed, and the first oil passage L2 is closed, as shown by the broken line in FIG. The oil passage L1 is connected to the oil cooler 68, the fourth oil passage L4 is connected to the sixth oil passage L6, and the fifth oil passage L5 is closed. The lockup control valve 64 includes a spring 64a that urges the spool valve to the OFF position side and an ON switching oil chamber 64b that receives the ON hydraulic pressure output from the ON / OFF solenoid valve SL to switch the spool valve to the ON position side. And have. When the supply of ON hydraulic pressure from the ON / OFF solenoid valve SL to the ON switching oil chamber 64b is stopped, the lockup control valve 64 holds the spool valve in the OFF position according to the urging force of the spring 64a and turns ON from the ON / OFF solenoid valve SL. When the ON hydraulic pressure is supplied to the switching oil chamber 64b, the spool valve is held in the ON position against the urging force of the spring 64a.

The hydraulic control circuit 54 configured as described above switches the hydraulic oil 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 switch the lockup clutch 32. The operating state can be switched. First, a case where the lockup clutch 32 is in the lockup state or the lockup slip state will be described. When the ON hydraulic pressure is output from the on / off solenoid valve SL according to the lockup control signal Slu output from the electronic control device 56 and supplied to the ON switching oil chamber 64b, the lockup control valve 64 is switched to the ON position. As a result, the hydraulic oil adjusted to the lockup control pressure Pslu is supplied from the oil passage L3 to the control oil chamber 20d of the torque converter 20 as the hydraulic oil of the lockup on pressure Plupon, and is adjusted to the modulator hydraulic pressure Pmod. The hydraulic oil is supplied from the oil passage L6 as the hydraulic oil of the torque converter in-pressure Ptcin to the front oil chamber 20e of the torque converter 20, and the hydraulic oil of the lockup out pressure Ptcout is discharged from the oil passage L1 to the discharge oil passage EX. To. In this case, the relationship between the magnitudes of the lockup-on pressure Plupon, the torque converter in-pressure Ptcin, and the torque converter out-pressure Ptcout is Plupon> Ptcin> Ptcout. Therefore, when the lockup on pressure Plupon, that is, the lockup control pressure Pslu of the control oil chamber 20d of the torque converter 20 is adjusted by the linear solenoid valve SLU according to the lockup control signal Slu, the lock corresponding to the lockup engagement pressure is applied. The up differential pressure ΔPlup is adjusted, and the operating state of the lockup clutch 32 is controlled within the range of the lockup slip state or the lockup state (fully engaged state). In the lockup slip state, the lockup differential pressure ΔPlup and the slip amount ΔN of the lockup clutch 32 can be continuously adjusted by controlling the lockup control pressure Pslu. In the lock-up slip state, the differential rotation ΔN between the engine speed Ne and the turbine speed Nt corresponds to the slip amount.

Next, the case where the lockup clutch 32 is in the lockup released state will be described. When the output of the ON hydraulic pressure from the on / off solenoid valve SL is stopped according to the lockup control signal Slu and the supply of the ON hydraulic pressure to the ON switching oil chamber 64b is stopped, the spool valve is moved according to the urging force of the spring 64a and locked. The up control valve 64 is switched to the OFF position. As a result, the hydraulic oil of the torque converter out pressure Ptcout that has flowed out from the hydraulic oil outflow port 20b of the torque converter 20 is supplied to the control oil chamber 20d of the torque converter 20 as the hydraulic oil of the lockup on pressure Plupon via the oil passages L1 and L3. At the same time, the second line hydraulic PL2 is supplied from the oil passage L6 to the front oil chamber 20e of the torque converter 20 as hydraulic oil for the torque converter in-pressure Ptcin. Further, a part of the hydraulic oil of the torque converter out pressure Ptcout that has flowed out from the hydraulic oil outflow port 20b is supplied to the oil cooler 68 from the oil passage L1. In this case, the relationship between the magnitudes of the lockup on pressure Plupon, the torque converter in pressure Ptcin, and the torque converter out pressure Ptcout is Ptcin> Ptcout> Plupon. As a result, the operating state of the lockup clutch 32 is switched to the lockup released state.

Returning to FIG. 1, the vehicle 10 has, for example, a lockup clutch control for controlling the lockup control pressure Pslu of the lockup clutch 32, that is, a lockup differential pressure ΔPlup, and a hydraulic friction engagement device CB at the time of shifting of the automatic transmission 22. The electronic control device 56 is provided as a controller that executes shift control and the like for controlling the engagement pressure of the vehicle via the hydraulic control circuit 54. The electronic control device 56 also serves as a controller for controlling the output (torque) of the engine 12. FIG. 1 is a diagram showing an input / output system of the electronic control device 56, and is a functional block diagram illustrating a main part of a control function by the electronic control device 56. The electronic control device 56 is configured to include, for example, a so-called microcomputer provided with a CPU, RAM, ROM, an input / output interface, etc., 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. Electronic control devices may be provided separately for engine control, shift control, and the like.

Various input signals detected by various sensors included in the vehicle 10 are supplied to the electronic control device 56. For example, it is a signal representing the throttle valve opening degree θth detected by the throttle valve opening degree sensor 70, a signal representing the vehicle speed V detected by the vehicle speed sensor 72, and the operating amount of the accelerator pedal detected by the accelerator operating amount sensor 74. A signal representing the accelerator operation amount θacc, a signal representing the ATF oil temperature Tool detected by the oil temperature sensor 76, a signal representing the rotation speed (engine rotation speed) Ne of the engine 12 detected by the engine rotation sensor 78, and a turbine rotation sensor. A signal indicating the rotation speed (turbine rotation speed) Nt of the turbine impeller 20t of the torque converter 20 detected by the 80, a signal indicating whether or not the sports mode in which driving performance is prioritized is selected by the sports mode selection switch 82, an eco mode. A signal or the like indicating whether or not the eco-mode having priority on fuel consumption is selected by the selection switch 84 is input to the electronic control device 56. The vehicle speed sensor 72 is arranged so as to detect, for example, the transmission output gear rotation speed Nout, which is the rotation speed of the transmission output gear 24, and the vehicle speed V can be calculated from the transmission output gear rotation speed Nout. Further, the turbine rotation speed Nt is the same as the transmission input shaft rotation speed Nin, which is the rotation speed of the transmission input shaft 30.

On the other hand, from the electronic control device 56, the engine control signal Se for controlling the operation of the engine 12, the shift control signal Sat for hydraulic control related to the shift of the automatic transmission 22, and the operation state of the lockup clutch 32 are switched. A lockup control signal Slu or the like for control is output. The engine control signal Se is a control signal that controls the opening and closing of the electronic throttle valve, the fuel injection amount by the fuel injection device, the ignition timing control, and the like, and controls the torque of the engine 12. The shift control signal Sat is a control signal for driving the linear solenoid valves SL1 to SL6 that control the engagement / release of the hydraulic friction engagement device CB. The lockup control signal Slu is a control signal for driving the linear solenoid valve SLU that regulates the lockup control pressure Pslu, and a control signal for driving the on / off solenoid valve SL that outputs the ON hydraulic pressure.

The electronic control device 56 functionally includes an engine control unit 100, a shift control unit 102, and a lockup clutch control unit 110. The engine control unit 100 basically controls the output of the engine 12 based on the accelerator operation amount θacc, the vehicle speed V, and the like. Further, the torque down control of the engine 12 is executed at the time of shifting in response to the request from the shifting control unit 102.

The shift control unit 102 makes a shift determination according to a predetermined shift map (shift condition) with, for example, the vehicle speed V and the output request amount such as the accelerator operation amount θacc as parameters, and if necessary, the gear stage of the automatic transmission 22. Is automatically switched, and manual shifting is performed by switching the gear stage of the automatic transmission 22 according to the shift instruction of the driver by the shift lever or the like. This shift control is performed by engaging / releasing the hydraulic friction engaging device CB via the linear solenoid valves SL1 to SL6, and the hydraulic pressure of the releasing side friction engaging device is depressurized in a predetermined change pattern. At the same time, the hydraulic pressure of the engaging side friction engaging device is increased in a predetermined change pattern. If necessary, a torque down command for the engine 12 or the like is output to the engine control unit 100.

The shift control unit 102 functionally includes a target time setting unit 104. The target time setting unit 104 uses, for example, a target shift time from the start of shift control to the end of shift control, a target start time from the start of shift control to the start of the inertia phase, and a target inertia time from the start of the inertia phase to the end of the shift (inertia phase end). Etc. is set based on the vehicle information. Vehicle information includes, for example, the type of shifting (upshift, downshift, shifting from which gear to which gear), power ON (driving state), power OFF (driven state), running mode (sports mode, normal mode). , Eco mode, etc.), ATF oil temperature Tool, transmission input torque Tin, vehicle speed V, accelerator operation amount θacc, etc., in consideration of shift shock, acceleration response, etc., or fuel efficiency, etc. The target time is set by a map or the like that uses one or more pieces of vehicle information as parameters (variables). Therefore, the target time is calculated from the map or the like based on the actual vehicle information. The shift control unit 102 sets the hydraulic pressure change pattern of the release side friction engagement device and / or the engagement side friction engagement device according to the target time. For example, when the hydraulic pressure change pattern changes the hydraulic pressure after a predetermined constant pressure standby, the constant pressure standby pressure is increased or decreased, the constant pressure standby time is increased or decreased, or the rate of change of the hydraulic pressure change after the constant pressure standby is increased or decreased. Further, when the hydraulic pressure is controlled so that the turbine rotation speed Nt (= transmission input shaft rotation speed Nin) changes at a predetermined rate of change in the inertia phase, for example, the target change rate of the turbine rotation speed Nt is set as the target inertia time. Set according to the above. As a result, it is possible to perform shift control with excellent drivability and fuel efficiency according to the vehicle condition.

The lockup clutch control unit 110 switches and controls the operating state of the lockup clutch 32, and functionally includes a complete lockup control unit 112, a flex lockup control unit 114, and a flex lockup control unit 116 during shifting. There is. The lockup clutch control unit 110 executes lockup control for controlling the lockup differential pressure ΔPlup of the lockup clutch 32, that is, the lockup control pressure Pslu. The lockup clutch control unit 110 uses, for example, a predetermined relationship (lockup area diagram) having a lockup off region, a slip operation region, and a lockup on region with the vehicle speed V and the throttle valve opening degree θth as parameters. Based on the actual vehicle speed V and the throttle valve opening degree θth, it is determined whether the region is the lockup-off region, the slip operating region, or the lockup-on region, and the operating state corresponding to the determined region is locked. The lockup control signal Slu is controlled so that the up clutch 32 is engaged. By driving (operating) the linear solenoid valve SLU and the on / off solenoid valve SL provided in the hydraulic control circuit 54 according to the lockup control signal Slu, the lockup clutch 32 is activated to the operating state corresponding to the determined region. The state is controlled.

The complete lockup control unit 112 is turned on and off so as to fully engage the lockup clutch 32 when it is determined in the lockup area diagram of the lockup clutch control unit 110 that it is the lockup on region. The ON hydraulic pressure is output from the solenoid valve SL, the lockup control valve 64 is held in the ON position, and the lockup control signal Slu that maximizes the lockup control pressure Pslu regulated by the linear solenoid valve SLU is generated. Perform lockup control to output. As a result, the lockup clutch 32 is in a lockup state (lockup on) in which the pump impeller 20p and the turbine impeller 20t are directly connected.

The flex lockup control unit 114 does not completely engage the lockup clutch 32 when the lockup area diagram of the lockup clutch control unit 110 determines that the flex lockup control unit 114 is in the slip operation region. Lockup control pressure Pslu (lockup on pressure Plupon) regulated by the linear solenoid valve SLU so that the difference rotation (slip amount) ΔN between 20p and the turbine impeller 20t becomes the preset target difference rotation ΔN *. ) Is output. The flex lockup control that outputs the lockup control signal Slu is performed. The target differential rotation ΔN * is set to a constant value in advance, for example, but can be variably set based on vehicle information. Also at this time, the ON hydraulic pressure is output from the on / off solenoid valve SL by the lockup control signal Slu, and the lockup control valve 64 is held in the ON position. As a result, the lockup clutch 32 is in a lockup slip state in which the differential rotation ΔN between the pump impeller 20p and the turbine impeller 20t becomes the target differential rotation ΔN *.

When the lockup area diagram of the lockup clutch control unit 110 determines that the lockup area is in the lockup off area, the ON hydraulic pressure from the on / off solenoid valve SL is released so as to release the lockup clutch 32. The lockup clutch release control that outputs the lockup control signal Slu that stops the output is performed. As a result, the lockup control valve 64 is held in the OFF position, and the lockup clutch 32 is released in the lockup release state (lockup off).

When the automatic transmission 22 is changed while the lockup clutch 32 is in the lockup state or the lockup slip state, the flex lockup control unit 116 at the time of shifting causes the lockup clutch 32 to be in the lockup slip state at the time of shifting. Therefore, flex lockup control during shifting is performed to output a lockup control signal Slu that controls the lockup control pressure Pslu adjusted by the linear solenoid valve SLU. Specifically, for example, the linear solenoid valve SLU is controlled so that the lockup control pressure Pslu becomes a predetermined target control pressure Pslu * during shifting. The shift target control pressure Pslu * is set based on, for example, whether the lockup clutch 32 at the start of shift control is in the lockup state or the lockup slip state, and various vehicle information. Vehicle information includes, for example, the type of shifting (upshift, downshift, shifting from which gear to which gear), power ON (driving state), power OFF (driven state), running mode (sports mode, normal mode). , Eco mode, etc.), ATF oil temperature Tool, engine torque Te, vehicle speed V, engine speed Ne, etc., in consideration of shifting shock, acceleration response, etc., or fuel efficiency, etc. The target control pressure Pslu * at the time of shifting is determined by a map or the like having one or more pieces of information as parameters. Therefore, the target control pressure Pslu * at the time of shifting is calculated from the map or the like based on the actual vehicle information. The target control pressure Pslu * at the time of shifting may be a constant value during the period of shifting control, but may be gradually changed. In addition, it is not always necessary to carry out the shifting time flex lock-up control over the entire shift control period, may be performed only during shifting flex lock-up control in the part of the change-speed control period. FIG. 8 is a time chart for explaining an example of the shift lockup control during shifting. The flex lockup control during shifting is performed over the entire shift control period of time t1 to t4, and in this example, the target control pressure during shifting Pslu * Is continuously changed. The electronic control device 56 functionally provided with the shift flex lockup control unit 116 corresponds to the control device of the vehicle power transmission device, and the shift target control pressure Pslu * corresponds to the lockup engagement pressure. ..

The shift flex lockup control unit 116 functionally includes a downshift initial decompression unit 118 that reduces the target control pressure Pslu * during shift (drain correction) at the initial stage of downshift shift control. That is, in the case of downshifting, in order to start the inertia phase more quickly than during upshifting, the target control pressure Pslu * during shifting is lowered as compared with that during flex lockup control before and after shifting, as shown in FIG. Since the movement of the pressing member 48 is hindered by the flow resistance due to the viscosity of the hydraulic oil and the decrease of the lockup differential pressure ΔPlup is delayed, the downshift initial decompression unit 118 further reduces the target control pressure Pslu * during shifting. Perform drain correction. At that time, in this embodiment, the drain correction amount α is set in consideration of the target time in the shift control. That is, in this embodiment, the downshift initial decompression unit 118 functions as a shift coordination unit. The drain correction amount α corresponds to the decompression range of the lockup engagement pressure during the flex lockup control during shifting.

Steps S1 to S8 of FIG. 6 (hereinafter, simply referred to as S1 to S8) are flowcharts for specifically explaining the shift lockup control by the shift flex lockup control unit 116, in which S7 is the downshift initial decompression unit 118. Corresponds to. In S1, it is determined whether or not the lockup control is being executed by the complete lockup control unit 112, and if the lockup control is being executed, whether or not the shift control by the shift control unit 102 is started in S2. That is, it is determined whether or not the hydraulic control for shifting has been started. If the shift control is not started, it ends as it is, but if the shift control is started, it is determined in S3 whether or not it is a downshift, and if it is not a downshift, that is, in the case of an upshift, the flex lock at the time of shifting in S8 is immediately performed. On the other hand, in the case of downshift, S7 is executed to perform drain correction by the downshift initial decompression unit 118, and then S8 is executed.

If the determination in S1 is NO (negative), that is, if the lockup control by the complete lockup control unit 112 is not being executed, S4 is executed and whether or not the flex lockup control by the flex lockup control unit 114 is being executed. To judge. If the flex lockup control is not being executed, the process ends as it is, but if the flex lockup control is being executed, S5 is executed and whether or not the shift control by the shift control unit 102 is started in the same manner as in S2. To judge. If the shift control is not started, it ends as it is, but if the shift control is started, it is determined in S6 whether or not it is a downshift, and if it is not a downshift, that is, in the case of an upshift, the flex lock at the time of shifting in S8 is immediately performed. On the other hand, in the case of downshift, S7 is executed to perform drain correction by the downshift initial decompression unit 118, and then S8 is executed.

The drain correction of S7 is performed at an appropriate timing for starting the inertia phase according to whether the lockup control or the flex lockup control is in progress before the shift control starts, and the shift control target time set by the target time setting unit 104. Calculate the drain correction amount α so that it is performed in. As shown in FIG. 7, the drain correction amount α is a predetermined correction amount with the difference between the target start time, which is the target time, and the synchronous rotation speed after shifting and the turbine rotation speed Nt (rotational difference during shifting) as parameters. Calculated from the map. In this correction amount map, for example, when the target start time is short, the drain correction amount α is larger than when it is long, and when the rotation difference during shifting is large, the drain correction amount α is larger than when it is small. It is stipulated to be done. In addition, the correction amount map is set separately for the case where the lockup control is in progress and the case where the flex lockup control is in progress.

FIG. 8 is an example of a time chart in the case where flex lockup control during shifting is performed according to the flowchart of FIG. 6 when the power is turned on, and the target control pressure Pslu * during shifting is the drain correction amount at the initial stage of downshifting. By lowering only α, the lockup differential pressure ΔPlup can be quickly lowered while moving the pressing member 48 regardless of the flow resistance of the hydraulic oil or the like. As a result, the differential rotation (slip amount) ΔN between the engine speed Ne and the turbine speed Nt is rapidly increased, and the start of the inertia phase is accelerated. On the other hand, the broken line in the time chart of FIG. 8 shows a change in the lockup differential pressure ΔPlop because the movement of the pressing member 48 is hindered by the flow resistance due to the viscosity of the hydraulic oil when the drain correction is not performed. Is delayed, the increase in differential rotation (slip amount) ΔN (increase in engine speed Ne) is delayed, and the progress of shifting may be delayed. The “SLU indicated pressure” in FIG. 8 is a command value of the lockup control pressure Pslu, and the actual lockup control pressure Pslu and the lockup differential pressure ΔPlup change later than the SLU indicated pressure.

Further, by setting the drain correction amount α according to the target start time, the target control pressure Pslu * at the time of shifting is appropriately corrected regardless of the difference in the target start time. As a result, the shift lockup control is appropriately performed by the shift target control pressure Pslu *, the downshift is appropriately advanced based on the target start time, the drivability is improved, and the differential rotation ΔN is excessive. Deterioration of fuel consumption due to the increase is suppressed. This drain correction is terminated before the start (time t2), which can be predicted from the target start time, that is, before the inertia phase starts. The time t1 in FIG. 8 is the start time of shift control, and is also the start time of flex lockup control during shift. The time t3 is the shift end determination time at which the turbine rotation speed Nt becomes the synchronous rotation speed after the shift, and the time t4 is the end time of the flex lockup control during the shift.

As described above, according to the electronic control device 56 of the vehicle power transmission device 16 of the present embodiment, during the flex lockup control during the shift according to the target time (target start time in the embodiment) used for the shift control. Since the drain correction amount α of the target control pressure Pslu * at the time of shifting corresponding to the slip state of, that is, the lockup engagement pressure is adjusted, the content of shifting control, specifically the above target, depends on the type of shifting and the traveling mode. Even if the time is different, the flex lockup control at the time of shifting is appropriately performed according to the target time, and the drive and fuel consumption can be improved.

Further, in this embodiment, since drain correction is performed at the initial stage of downshift shift control to further reduce the target control pressure Pslu * during shift, the pressing member 48 is locked while being moved regardless of the flow resistance of hydraulic oil or the like. The up differential pressure ΔPlup can be rapidly reduced. As a result, the differential rotation (slip amount) ΔN between the engine speed Ne and the turbine speed Nt is rapidly increased, the inertia phase starts earlier, the downshift is quickly executed, and the acceleration performance and the like are driven. improves.

Although describes the drain complement Masanitsu to further reduce the shift time target control pressure PSLU * at the initial stage of the shift control of the downshift in the above embodiment, if example embodiment, the gear shifting flex lock-up control during upshifting Can also apply similar controls . Further, as shown in FIGS. 9 and 10, it can be applied to the case where the flex lockup control at the time of shifting is executed in the inertia phase in which the turbine speed Nt changes. Specifically, for example, as shown in the following equation (2), the target change rate ΔNt * of the turbine rotation speed Nt in the inertia phase is multiplied by the gain A, and the correction term B regarding the static target difference rotation ΔN, the input torque. The correction term C for Tin and the correction term D for the target inertia time, which is the target time in shift control, are added to calculate the shift target control pressure Pslu *, which is linear so as to be the shift target control pressure Pslu *. The lockup control pressure Pslu is controlled via the solenoid valve SLU. The gain A is, for example, the type of shift (upshift, downshift, shift from which gear to which gear), power ON (driving state), power OFF (driven state), running mode (sports mode, normal mode). , Eco mode, etc.), ATF oil temperature Tool, engine torque Te, vehicle speed V, engine speed Ne, etc., and determined in advance in consideration of shift shock, acceleration response, etc., or fuel efficiency. It is obtained from the obtained map etc. For example, in the upshift of FIG. 9, the flex lockup control unit 114 before and after the shift is used to suppress deterioration of fuel consumption due to an increase in the differential rotation (slip amount) ΔN between the engine speed Ne and the turbine speed Nt. The target control pressure Pslu * during shifting is higher than that during normal flex lockup control. Further, in the downshift of FIG. 10, in order to suppress the shift shock at the end of the shift, the target control pressure Pslu * during the shift is lower than that during the normal flex lockup control by the flex lockup control unit 114 before and after the shift. .. In FIGS. 9 and 10, the time t1 is the shift control start time, the time t2 is the inertia phase start time, and the time t3 is the shift end time (inertia phase end time), and the shift target control pressure Pslu * The SLU indicated pressure before and after is a value at the time of normal flex lockup control by the flex lockup control unit 114.
Pslu * = ΔNt * × A + B + C + D ・ ・ ・ (2)

Here, the solid line in the column of the SLU indicated pressure in FIG. 9 regarding the upshift is such that the difference rotation (slip amount) ΔN between the engine speed Ne and the turbine speed Nt does not become excessive when the target inertia time is short. , The target control pressure Pslu * at the time of shifting is higher than when the target inertia time is long. Further, the solid line in the column of the SLU indicated pressure in FIG. 10 regarding downshift is when the target inertia time is short, and the target control pressure Pslu * at the time of shifting is lower than when the target inertia time is long in order to suppress the shift shock. Be squeezed. By adjusting the target control pressure Pslu * during shifting according to the target inertia time of shifting control in this way, even if the target inertia time differs depending on the type of shifting, running mode, etc., the target inertia time is adjusted. Flex lockup control during shifting will be performed appropriately, and it will be possible to improve driving and fuel efficiency.

Note that the alternate long and short dash line in the SLU indicated pressure column in FIGS. 9 and 10 changes the start time and end time of the flex lockup control during shifting based on the target time such as the target inertia time or other vehicle information. Or, the SLU indicated pressure is gradually changed at the start and end of the flex lockup control during shifting.

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.

For example, the torque converter 20 of the above-described embodiment has a hydraulic oil supply port 20a, a hydraulic oil outflow port 20b, and a port for supplying a lockup control pressure Pslu to the control oil chamber 20d, and moves the pressing member 48. Although it had a 3-port structure in which the multi-plate lockup clutch 32 was engaged and released, the present invention can also be applied to a torque converter or the like having a 2-port structure. Further, a single plate type lockup clutch can be adopted instead of the multi-plate type lockup clutch 32.

Further, in the above embodiment, the lockup differential pressure ΔPlup, which is the lockup engagement pressure, is controlled by the lockup control pressure Pslu (lockup on pressure Plupon), but the lockup engagement pressure is directly controlled by a linear solenoid valve or the like. A controllable lockup clutch or torque converter can also be used.

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

12: Engine (motor) 16: Power transmission device for vehicle 22: Automatic transmission 32: Lockup clutch 56: Electronic control device (control device) 102: Shift control unit 104: Target time setting unit 116: Flex lockup during shift Control unit 118: Downshift initial decompression unit (shift coordination unit) Pslu *: Target control pressure during shift (lockup engagement pressure) α: Drain correction amount (decompression width)

Claims (1)

It is provided in a vehicle power transmission device provided with a frictional engagement type lockup clutch between the prime mover and the automatic transmission, and the lockup clutch is engaged in a predetermined slip state when the automatic transmission is changed. In the control device of the power transmission device for a vehicle having the shift-shift flex lock-up control unit that executes the shift-shift flex lock-up control that controls the lock-up engagement pressure .
During the downshift of the automatic transmission, a predetermined target time associated with the transmission is set based on the vehicle information Rutotomoni, the target time of the target Suberidashi time or speed-change control from the start of the shift control to the inertia phase start It is a target shift time from the start to the end of the shift, and while shift control of the automatic transmission is performed according to the target time,
The flex lockup control unit at the time of shifting controls the lockup engagement pressure so that the lockup clutch is in the predetermined slip state at the time of downshifting of the automatic transmission, and the inertia phase of the downshift. The lockup engagement pressure is reduced in the initial stage before the start of the operation, and when the target time is short, the pressure reduction width of the lockup engagement pressure in the initial stage is larger than when the target time is long. the control device for a vehicular power transmission device, characterized in that it comprises a speed change coordination unit for adjusting the pressure decrease of the lock-up engagement pressure in the initial stage in response to the target time.

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