JPH0958302A - Controller of directly connected clutch for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent generation of shifting shock in conducting operation for increasing the speed of an engine, relating to an acceleration pedal being kept in a non-operating condition, and at the same time, in conducting shifting-up operation. SOLUTION: By an engine speed-down restraining start control means 194, operation for increasing the speed of an engine is started when the final timing, of off shifting-up is determined by a speed change final timing determining means 196, therefore, no delay is made even when off shifting-up of an automatic transmission 14 is carried out for the non-operating condition of the accelerator pedal as compared with the case where an ISC valve 83 is opened by a prescribed amount with the accelerator pedal kept in the non-operating condition. It is thus possible to prevent generation of shifting shock suitably.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle direct-coupling clutch control device, and more particularly to a technique for preventing shift shock when a shift-up shift and slip control of a direct-coupling clutch are performed at the start of deceleration of a vehicle. It is a thing.

[0002]

2. Description of the Related Art A direct coupling clutch that directly couples a pump impeller and a turbine impeller of a fluid transmission device such as a torque converter or a fluid coupling, and an automatic gear shift to any one of a plurality of gear stages. Vehicles having a transmission are known. Then, in such a vehicle, in order to increase the engine rotation speed and expand the fuel cut region, it is conceivable to engage the direct coupling clutch or slip a predetermined amount when the vehicle is decelerated.

However, when the direct coupling clutch is engaged or a predetermined amount is slipped when the vehicle starts decelerating, it may be difficult to engage the direct coupling clutch or the slip control may become unstable. . On the other hand, when the direct coupling clutch is engaged or the vehicle slips by a predetermined amount at the start of deceleration traveling of the vehicle, the engine rotation speed reduction suppression that suppresses the reduction speed of the engine rotation speed of the vehicle that was in the driving state until then is suppressed. A technique has been proposed in which the means is provided to facilitate the engagement of the direct coupling clutch and to stably start the slip control.
For example, it is the control device for a vehicle lock-up clutch described in JP-A-5-225403.

[0004]

By the way, in the above-mentioned conventional control device, when it is detected that the accelerator pedal is in the non-operated state and the throttle valve is fully closed, the engine rotation speed reduction suppressing means is operated. Since the output is performed, for example, the idle rotation speed control valve (ISC valve) of the idle rotation speed control device (ISC) is opened by a predetermined amount. When an upshift shift (power-off upshift) is executed, the engine output torque is increased during the shift due to the opening of the idle rotation control valve, and the decrease in the engine rotation speed slows down. There is an inconvenience that the driving torque at that time fluctuates and a shift shock occurs. Further, depending on the operation output amount of the engine rotation speed decrease suppressing means, a driving state of the vehicle in which the engine rotation speed exceeds the turbine impeller rotation speed temporarily occurs within the deceleration slip start period, and the driver feels uncomfortable. There was a problem of giving.

The present invention has been made in view of the above circumstances. A first object of the present invention is to perform an upshift gear shift in connection with the accelerator pedal being in a non-operated state. Another object of the present invention is to provide a control device for a direct clutch for a vehicle, in which a shift shock is prevented. A second object of the present invention is to provide a vehicle direct-coupling clutch control device that does not cause a feeling of strangeness due to the engine rotation speed exceeding the turbine impeller rotation speed at the start of deceleration slip control.

[0006]

The first object of the present invention to achieve the first object is to provide a direct coupling clutch for directly connecting a pump impeller and a turbine impeller of a fluid transmission device. In a vehicle having an automatic transmission that automatically shifts to any of a plurality of gears, a deceleration slip control means for performing slip control of a direct coupling clutch during deceleration traveling of the vehicle, and the deceleration slip control means A control device comprising an engine rotation speed reduction suppressing means for suppressing a decrease in engine rotation speed at the start of slip control, wherein (a) the automatic transmission executed in association with non-operation of the accelerator pedal. An end-of-shift determination means for determining whether or not the upshift shift reaches a predetermined end-of-shift, and (b) the end-of-shift determination means for determining the shift of the automatic transmission. Since the period is determined, the engine rotational speed decrease suppression start control means for starting operation of the engine rotational speed decrease suppression means is to include.

[0007]

With the above arrangement, the engine rotation speed decrease suppression start control means operates the engine rotation speed decrease suppression means from the time when the shift end determination means determines the end of the shift of the automatic transmission. Since the operation is started, as compared with the case where the operation of the engine speed reduction suppressing means is started when the accelerator pedal is not operated, the throttle valve is fully closed. Even if the upshift gearshift of the automatic transmission is executed, there is no delay in the decrease of the engine rotation speed, and the gearshift shock resulting from that is suitably prevented. Further, as a result of the engine rotation speed reduction suppressing means starting the operation of suppressing the decrease in the engine rotation speed from the time when the end of the shift is determined, the engine rotation speed reduction suppressing effect causes the engine rotation speed to decrease. Since the slip control is substantially started by the deceleration slip control means in the state in which the engine rotation speed is close to, the slip control becomes stable from the beginning, and the engine rotation speed exceeds the turbine impeller rotation speed. A feeling of strangeness is preferably prevented.

[0008]

Another aspect of the present invention is preferably that the shift end determination means determines the end of shift based on a vehicle state including an actual gear stage from a preset relationship. As a result, it is possible to execute favorable engine rotation speed reduction suppression control for various gears. More preferably, the end-of-shift determination means is a rotating member whose rotational speed decreases in association with an upshift transmission of the automatic transmission, that is, the rotational speed of a turbine impeller of a fluid transmission, the input shaft rotation of the automatic transmission. The end of shift is determined when the rotational speed such as the speed becomes equal to or lower than a predetermined end of shift determination reference value.The end of shift determination reference value is an actual vehicle running state based on a preset relationship. It is decided based on. This relationship has been experimentally obtained in advance in accordance with the running state of the vehicle so that the response delay time of the engine rotation speed control device is advanced from the end of the shift, so that the end-of-shift determination means is eventually determined. Is to determine the end of the shift at a time point when the response delay time of the engine rotation speed control device goes back from the end time of the shift. With this configuration, there is an advantage that the delay of the decrease in the engine rotation speed is minimized according to the vehicle state including the gear stage and the engine rotation speed decrease suppression effect is reliably generated at the start of the slip control. is there.

Further, preferably, the engine rotation speed decrease suppressing means changes its control output based on a vehicle state including a gear stage. As a result, it is possible to execute favorable engine rotation speed reduction suppression control for various gears. More preferably, the engine rotation speed reduction suppressing means is an idle rotation speed control device including an idle rotation speed control valve provided in parallel with a throttle valve for adjusting the idle rotation speed of the engine. The opening degree of the idle rotation speed control valve when the operation for suppressing the decrease in the engine rotation speed is started by the rotation speed reduction suppression start control means is based on the actual traveling state of the vehicle from a preset relationship. It is determined. This relationship is that when the slip control is started by the deceleration slip control means, the gear stage is set to determine the opening degree of the idle rotation speed control valve so that the engine rotation speed and the rotation speed of the turbine impeller are substantially matched. Since it has been experimentally obtained in advance according to the running state of the vehicle including, the engine rotation speed and the rotation speed of the turbine impeller are made to substantially match at the end of the gear shift, that is, the start of the deceleration slip control. There is an advantage.

[0010]

[Second Means for Solving the Problems] The gist of the second invention for achieving the second object is as follows.
In a vehicle having a direct coupling clutch that directly connects between a pump impeller and a turbine impeller of a fluid transmission, and an automatic transmission that automatically shifts to any one of a plurality of gear stages, when the vehicle is decelerated. A deceleration slip control means for executing slip control of a direct coupling clutch, and a control device provided with an engine rotation speed reduction suppressing means for suppressing a decrease in engine rotation speed at the start of slip control by the deceleration slip control means, a) a drive state determination means for determining whether or not the vehicle is in a drive state when the reduction in engine speed is suppressed by the engine rotation speed reduction control means, and (b) by the drive state determination means. And an operation stopping means for stopping the operation of the engine rotation speed reduction suppressing means when it is determined that the vehicle is in a driving state. In the door.

[0011]

With the above arrangement, when the drive state determining means determines that the vehicle is in the drive state, the operation stopping means stops the operation of the engine rotation speed decrease suppressing means. For this reason, the engine rotation speed reduction suppressing operation by the engine rotation speed reduction suppressing means is canceled and the increasing tendency of the engine rotation speed from the original value is canceled, so that the engine rotation speed falls below the rotation speed of the turbine impeller. The deceleration slip control is stably continued, and the discomfort caused by the engine rotation speed exceeding the rotation speed of the turbine impeller is eliminated.

[0012]

Another aspect of the present invention, preferably, when the drive state determining means determines that the vehicle is in the drive state, the control output from the engine rotation speed decrease suppressing means at the time of the next slip control. Learning correction means for learning correction is further provided. This learning correction value is determined to the side where the drive state determination means no longer determines that the vehicle is in the drive state. By doing so, there is an advantage that the vehicle is preferably prevented from being driven at the start of the next deceleration slip.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a skeleton view of an automatic transmission for a vehicle, the shift of which is controlled by a hydraulic control device according to an embodiment of the present invention. In the figure, an output of an engine 10 is input to an automatic transmission 14 via a torque converter 12 and transmitted to driving wheels via a differential gear device and an axle (not shown).

The torque converter 12 is used to
Pump impeller 18 connected to the crankshaft 16 of 0 and turbine impeller 2 connected to the input shaft 20 of the automatic transmission 14.
2 and the pump impeller 18 and the turbine impeller 22 are directly connected to each other, the piston 2 fitted in the hub shaft of the turbine impeller 22 so as to be axially movable and non-rotatable relative to each other.
A lock-up (directly connected) clutch 24 connected to the input shaft 20 via a shaft 3 and a stator 28, which is prevented from rotating in one direction by a one-way clutch 26, are provided.

The automatic transmission 14 includes a first transmission 30 for switching between high and low gears and a second transmission 32 for switching between reverse gears and forward gears. The first transmission 30 includes an HL planetary gear device 34 including a sun gear So, a ring gear Ro, and a planetary gear Po rotatably supported by the carrier Ko and meshed with the sun gear So and the ring gear Ro, a sun gear So and a carrier. It includes a clutch Co and a one-way clutch Fo provided between Ko and a brake Bo provided between the sun gear So and the housing 41.

The second transmission 32 has a first planetary gear unit 36 comprising a sun gear S1, a ring gear R1, and a planet gear P1 rotatably supported by the carrier K1 and meshed with the sun gear S1 and the ring gear R1.
, Sun gear S2, ring gear R2, and carrier K
2 and a second planetary gear unit 38, which is rotatably supported by the sun gear S2 and a ring gear R2 and is meshed with the sun gear S2 and the ring gear R2, and the sun gear S3, the ring gear R3, and the carrier K3, which are rotatably supported by the sun gear S2. S3 and a third planetary gear set 40 including a planet gear P3 meshed with the ring gear R3.

The sun gear S1 and the sun gear S2 are integrally connected to each other, the ring gear R1, the carrier K2, and the carrier K3 are integrally connected, and the carrier K3 is connected to the output shaft 42. Further, a ring gear R2 is integrally connected to the sun gear S3. A clutch C1 is provided between the ring gear R2 and the sun gear S3 and the intermediate shaft 44, and the sun gear S1 and the sun gear S3 are provided.
A clutch C2 is provided between the shaft 2 and the intermediate shaft 44. A band-type brake B1 for stopping rotation of the sun gear S1 and the sun gear S2 is provided on the housing 41.
It is provided in. A one-way clutch F1 is provided between the housing 41 and the sun gear S1 and the sun gear S2.
And the brake B2 are provided in series. The one-way clutch F1 is configured to be engaged when the sun gear S1 and the sun gear S2 try to reversely rotate in the direction opposite to the input shaft 20.

A brake B3 is provided between the carrier K1 and the housing 41, and a brake B4 and a one-way clutch F2 are provided between the ring gear R3 and the housing 41 in parallel. This one-way clutch F
2 is configured to be engaged when the ring gear R3 attempts to rotate in the reverse direction.

In the automatic transmission 14 configured as described above, the first reverse gear and the fifth forward gear are switched according to, for example, an operation table shown in FIG. In FIG. 2, ○ indicates an engaged state, X indicates a disengaged state, and ◎ indicates that the lock-up clutch 24 is operated when engaged or slipped. As is apparent from FIG. 2, the clutch C2 is engaged during the 3 → 4 shift from the third gear to the fourth gear, and the fourth gear from the fourth gear to the fifth gear is engaged. → Clutch C0 for 5 shifts
Is released and the brake B0 is engaged.
In the fourth gear, the input shaft 20 and the output shaft 42 of the automatic transmission 14 have the same rotation speed.

As shown in FIG. 3, the engine 10 of the vehicle
The intake pipe is operated by an accelerator pedal 50
First throttle valve 52 and throttle actuator 54
And a second throttle valve 56 operated by
ing. In addition, an engine that detects the rotation speed of the engine 10
The gin rotation speed sensor 58, the intake air amount of the engine 10
Intake air amount sensor 60 for detecting, temperature of intake air is detected
Intake air temperature sensor 62, the first throttle valve 5
Throttle with an idle switch that detects the opening degree TA of 2
The vehicle speed V is detected from the rotation speed of the sensor 64 and the output shaft 42.
The vehicle speed sensor 66 and the cooling water temperature of the engine 10 are detected.
Cooling water temperature sensor 68 to detect the operation of the brake
Set the operating positions of the brake switch 70 and shift lever 72.
An operation position sensor 74 for detecting is provided.
From these sensors, the engine speed N_E, Intake air volume
Q, intake air temperature THa, opening T of the first throttle valve T
A, vehicle speed V, engine cooling water temperature THw, brake operation
A signal indicating the state BK and the operation position Psh of the shift lever 72
Is an electronic control unit for engine 76 and an electronic control unit for shifting.
It is designed to be supplied to the storage 78. Also turbine
Rotational speed N of impeller 22 _TOr clutch of clutch C0
Drum rotation speed (clutch rotation speed) N_CODetect
Therefore, the input shaft rotation speed N is substantially_INTo detect
-Bin rotation speed sensor 75 and hydraulic oil temperature
From the oil temperature sensor 77 to the turbine rotation speed N_TAnd actuation
Oil temperature T_OILTo the electronic shifting control device 78.
Supplied respectively.

The engine electronic control unit 76 includes a CPU,
A so-called microcomputer having a RAM, a ROM, and an input / output interface, the CPU processes an input signal according to a program stored in the ROM in advance while utilizing a temporary storage function of the RAM, and executes various engine controls. For example, the fuel injection valve 80 is controlled for controlling the fuel injection amount, the igniter 82 is controlled for controlling the ignition timing, and the throttle valve 52, 56 is provided in parallel for controlling the idle speed of the engine 10. The ISC (idle rotation speed control valve) valve 83 is controlled, and the second throttle valve 56 is controlled by the throttle actuator 54 for traction control and the like. In the fuel cut control, for example, when the vehicle is decelerating while the first throttle valve 52 is in the fully closed state, the engine rotation speed N is higher than the predetermined fuel cut rotation speed N _cut.
During the period when _E is high, the fuel injection valve 80 is closed. In the present embodiment, the engine electronic control unit 76 decreases the engine rotation speed N _E by opening the ISC valve 83 and increasing the fuel supply amount during deceleration slip control or during upshift shifting executed together therewith. Since it suppresses the speed, it functions as an engine rotation speed decrease suppressing means.

The shift electronic control unit 78 is also a microcomputer similar to the above, and the CPU processes input signals in accordance with a program stored in the ROM 79 in advance while utilizing the temporary storage function of the RAM. Of each solenoid valve or linear solenoid valve. For example, the electronic control unit 78 for the speed change
The linear solenoid valve _SLT to generate an output pressure P _SLT having a magnitude corresponding to the opening degree TA, the linear solenoid valve SLN to control the accumulator back pressure, and the lockup clutch 24 to engage or slip. Each drive a linear solenoid valve SLU to control the quantity.
Further, the electronic shift control device 78 determines the gear position of the automatic transmission 14 and the engagement state of the lock-up clutch 24 based on the actual throttle valve opening TA and the vehicle speed V from the previously stored shift diagram. , The solenoid valve S1, S2, S3 is driven so as to obtain the determined gear stage and engagement state, and the solenoid valve S4 is used when engine braking is generated.
Is not driven.

The electronic shift control device 78 further executes engagement control and slip control of the lockup clutch 24, and releases the lockup clutch 24 at the first speed gear and the second speed gear of the automatic transmission 14. However, for the third speed gear and the fourth speed gear, the relationship shown in FIG. 4, for example, corresponding to the gear speed of the automatic transmission 14 is selected from a plurality of types of relationships stored in the ROM 79 in advance. Based on the throttle valve opening TA and the vehicle speed (transmission output shaft rotation speed) V, the release, slip, or engagement region is determined. If the release or engagement region is reached, the lockup clutch 24 is released. Alternatively, it is engaged. In the slip region, the electronic shift control device 78 executes slip control of the lockup clutch 24.

In the slip control, the rotational loss of the torque converter 12 is reduced by absorbing the rotational fluctuation of the engine 10 for the purpose of improving the fuel efficiency as much as possible without impairing the drivability in the driving state of the vehicle. Is suppressed as much as possible, the lock-up clutch 24 is maintained in the slip state. Further, even in a non-drive traveling state or during deceleration coasting of the vehicle, for the purpose of enlarging the control area of the fuel-cut control of the engine rotational speed N _e and higher than the fuel-cut rotational speed N _cut, deceleration lock-up clutch 24 Slip control is executed. This deceleration slip control is executed under the conditions that the throttle valve opening TA is zero, the vehicle speed V is a predetermined value or more, and the like.

In the above-described slip control, the actual slip amount N _{slip is calculated} according to a slip control routine (not shown).
(= N _E −N _T ) is calculated so that the preset target slip amount N _slip ^T and the actual slip amount N _slip match, for example, according to the following equation (1), the linear solenoid valve SLU.
Is calculated, that is, the drive duty ratio DSLU (%) is calculated, and the control pressure P _SLU output from the linear solenoid valve _SLU is adjusted. DSLU = DFWD + DFB (1)

In the above equation (1), DFWD is, for example,
Feedforward as a function of engine 10 output torque
DFB is, for example, the target slip
Quantity N _slip ^TAnd actual slip amount N_slipDeviation between and ΔE (=
N_slip-N_slip ^T) Feedback system to eliminate
It is the output value. These DFWD and DFB are
The amount is converted into a ratio and its unit is%. the above
The feedback control output value DFB is the well-known PI.
It is calculated from the D control formula. Note that in equation (1)
The load of the feedback control output value DFB is reduced.
A learning correction term to eliminate it is provided if necessary.
You.

FIG. 5 shows a main part of the hydraulic control circuit 84. In the figure, a linear solenoid valve SLU that functions as a control pressure generation valve is a pressure reducing valve that uses the modulator pressure P _M as a source pressure, and as shown in FIG. 6, a drive duty ratio output from the electronic shift control device 78. The control pressure P _SLU that increases with the DSLU is output and supplied to the lockup relay valve 98 and the lockup control valve 100.

The lock-up relay valve 98 is capable of abutting on each other, and has a first spool valve element 104 and a second spool valve element 1 having a spring 102 interposed therebetween.
06 and the first spool valve element 104 and the second spool valve element 1 provided on the shaft end side of the first spool valve element 104.
Output pressure P to bias 06 to the position on the engagement (ON) side.
Oil chamber 108 for receiving _SLU and first spool valve 10
And an oil chamber 110 for receiving the second line pressure P _L2 for urging the fourth and second spool valve elements 106 to the release side position. The first spool valve 104 is released (OF).
When located in the F) side position, the second line pressure P _L2 supplied to the input port 112 is supplied from the release side port 114 to the release side oil chamber 116 of the torque converter 12, and at the same time, the engagement side of the torque converter 12 is reached. The hydraulic oil in the oil chamber 118 is discharged from the engagement side port 120 through the discharge port 122 to the cooler bypass valve 124 or the oil cooler 126. On the contrary, when the first spool valve element 104 is located at the engagement side position, the second line pressure P _L2 supplied to the input port 112 is supplied from the engagement side port 120 to the engagement side oil chamber 118 of the torque converter 12. As supplied,
The hydraulic oil in the release-side oil chamber 116 of the torque converter 12 is discharged from the release-side port 114 through the discharge port 128, the control port 130 of the lock-up control valve 100, and the discharge port 132.

Therefore, when the output pressure P _SLU is less than or equal to the predetermined value, the first spool valve element 104 follows the thrust based on the second line pressure P _L2 and is on the release side (OFF) shown on the right side of the center line in FIG. When the output pressure P _SLU exceeds a predetermined value, the first spool valve element 104 moves from the center line of FIG. 5 according to the thrust based on the second line pressure P _L2 . The lockup clutch 2 is located at the engagement side (ON) position shown on the left side.
4 is engaged or slipped. The engagement or slip state of the lockup clutch 24 at this time is controlled by the lockup control valve 100 which operates according to the magnitude of the output pressure P _SLU .

The lockup control valve 100 is for controlling the slip amount of the lockup clutch 24 in accordance with the output pressure P _SLU when the lockup relay valve 98 is at the engagement side position, and the spool valve element 134.
5, a plunger 136 that abuts on the spool valve element 134 and applies thrust to the discharge side position shown on the right side of the center line in FIG. 5, and a supply side position shown on the left side of the spool valve element 134 in the center line of FIG. A spring 138 for applying a thrust force toward the spring 138 and an oil receiving the oil pressure P _ON in the engagement side oil chamber 118 of the torque converter 12 for accommodating the spring 138 and biasing the spool valve element 134 toward the supply side position. A chamber 140 and an oil chamber 142 provided on the shaft end side of the plunger 136 for receiving the oil pressure P _OFF in the release side oil chamber 116 of the torque converter 12 for urging the spool valve element 134 toward the discharge side position; , Plunger 1
And an oil chamber 144 which is provided in the middle portion of 36 and receives the output pressure P _SLU .

For this reason, when the spool valve element 134 is positioned at the discharge side, the control port 130 and the discharge port 132 are communicated with each other, so that the engagement torque of the lock-up clutch 24 is increased. Conversely, when the control port 130 is located at the supply side position, the supply port 146 to which the first line pressure P _L1 is supplied communicates with the control port 130, so that the first line pressure P _L1 is connected to the release side of the torque converter 12. The engagement torque of the lock-up clutch 24 supplied to the oil chamber 116 is reduced. That is, in the lockup control valve 100, the differential pressure between the oil pressure in the engagement side oil chamber 118 of the torque converter 12 and the oil pressure in the release side oil chamber 116, that is, the engagement torque of the lockup clutch 24 is the output pressure P. It is controlled according to _SLU .

Therefore, as the output pressure P _SLU increases above the predetermined value, the engagement torque of the lock-up clutch 24 is increased to reach full engagement. When the lockup clutch 24 is released, the linear solenoid valve SLU is driven by the electronic shift control device 78 so that the output pressure P _SLU becomes a value smaller than the predetermined value. When the lockup clutch 24 is engaged, the linear solenoid valve SLU is driven by the electronic shift control device 78 so that the output pressure P _SLU becomes the maximum value, and when the lockup clutch 24 is slipped. The linear solenoid valve SLU is driven by the electronic shift control device 78 so that the output pressure P _SLU is between the predetermined value and the maximum value. That is, in the lockup control valve 100, as shown in FIG. 7, the hydraulic pressure P _on in the engagement side oil chamber 118 of the torque converter 12 and the hydraulic pressure P _off in the release side oil chamber 116 are the control pressure P.
Since it is changed according to the _SLU, the engagement torque of the lockup clutch 24 corresponding to the engagement pressure, that is, the differential pressure (P _on -P _off ) between the hydraulic pressures P _on and P _off is also the control pressure _{SL U.}
The slip amount N _slip is controlled by changing the slip amount.

The solenoid relay valve 170 is connected to the output port 1 connected to the oil chamber 108 of the lock-up relay valve 98.
72, drain port 174, linear solenoid valve SL
The input port 176 to which the output pressure P _{SLU of} U is supplied, the lock-up release position for communicating the output port 172 with the drain port 174, and the output port 172 are the input port 17
6, a spool valve 178 that is switched to a lock-up allowing position that communicates with the valve 6, and a spring 18 that urges the spool valve 178 toward the lock-up allowing position.
0, and the engagement pressure P _{B2 of the} brake B2 that is generated in the gears equal to or higher than the third gear for accommodating the spring 180 and biasing the spool valve element 178 toward the lockup permission position. An oil chamber 182 that receives via the orifice 181 and an oil chamber 184 that receives the first line pressure P _L1 for urging the spool valve 178 toward the lockup release position are provided. As a result, in the lockup relay valve 98, the output pressure P _SLU is set in the oil chamber 10 only in the third and higher gear stages.
8 and can be engaged according to its output pressure P _SLU (O
It can be switched to the N) side position. Since the second line pressure P _L2 is adjusted by reducing the first line pressure P _L1 , the first line pressure P _L2 is adjusted.
_L1 is always higher than the second line pressure P _L2 .

An oil passage 186 is provided between the linear solenoid valve SLU and the oil chamber 144 of the lockup control valve 100, and the output pressure P _SLU output from the linear solenoid valve _SLU is the solenoid relay valve. 1
The oil is supplied directly to the oil chamber 144 of the lock-up control valve 100 without passing through 70. The oil passage 186 is provided to operate the lockup control valve 100 by the output pressure P _SLU even at the second speed or lower, thereby enabling detection of an abnormality in which the lockup relay valve 98 is located on the engagement side. There is.

FIG. 8 is a functional block diagram for explaining the main part of the control function of the electronic shift control device 78. In the figure, a shift control unit 190 executes a well-known shift control for automatically changing the gear stage of the automatic transmission 14. That is, the shift control unit 190 makes a shift determination based on a vehicle state represented by, for example, the throttle valve opening TA and the vehicle speed V from a well-known shift diagram, and realizes the shift determined. Shift output is performed. Since the shift lines that make up the above shift diagram are provided so that the vehicle speed becomes higher as the throttle valve opening TA increases, when the accelerator pedal 50 is not operated while the vehicle is traveling, the shift line is 3 An upshift such as a → 4 shift or a 4 → 5 shift is executed.

The deceleration slip control means 192 controls the slip-up of the lock-up clutch 24 when the accelerator pedal 50 is not operating (when the idle switch is on), which is referred to as non-driving traveling of the vehicle, power-off traveling, or decelerating traveling. Run. In this slip control, the actual slip amount N
_slip (= N _E −N _T ) is calculated so that the preset target slip amount N _slip ^T and the actual slip amount N _slip coincide with each other, for example, according to the equation (1).
The drive duty ratio DSLU (%) to the SLU, that is, the engagement torque of the lockup clutch 24 is adjusted. Further, at the start of the slip control, the deceleration slip control means 192 outputs a relatively high command value DSLU of, for example, about 80% in the initial boosting period in order to improve the responsiveness as shown in FIG. 12, for example. However, the command value DSL for generating a standby pressure that is set to a level just before the engagement torque of the lockup clutch 24 is generated.
U is output in the standby pressure period, and a relatively high command value DSLU of about 80% is output in the engagement start period in order to quickly and slip-engage the lockup clutch 24 in synchronism with the end of the gear shift. , A deceleration slip that outputs a command value DSLU for increasing the engagement torque of the lockup clutch 24 in the engagement start period so that the actual slip amount N _slip becomes approximately the target slip amount N _slip ^T prior to the feedback control of the deceleration slip. Perform start-time control.

The engine speed reduction suppressing means (engine electronic control unit 76) is the deceleration slip control means 1 described above.
When the deceleration slip control by 92 is started, the ISC valve 83
By increasing the fuel supply amount as SLUISC which is previously determined based on the vehicle state, that is, the vehicle speed V and the gear stage G, the engine rotation in the process of decreasing from the previous value after the accelerator pedal 50 is not operated. The decrease speed of the speed N _E is suppressed according to the opening degree of the ISC valve 83.

The gear shift end determination means 196 determines that the upshift (off-up) gear shift executed by the gear shift control means 190 in association with the non-operation of the accelerator pedal 50 is a predetermined gear shift end before the end of the gear shift. It is determined whether it has arrived. Then, the engine rotation speed reduction suppression start control means 194, from when the end of the upshift gear shift is judged by the gear shift end judgment means 196,
The operation for suppressing the decrease in the engine rotation speed N _E is started by the engine rotation speed decrease suppressing means. As a result, the engine rotational speed N _E is set to a value near the turbine rotational speed N _T lower than the turbine rotational speed N _T by the target slip amount immediately before the end of the upshift shift.

The shift end determination means 196 determines a shift end determination reference value NISCE for which the rotational speed of the rotating member, for example, the clutch rotational speed N _C0, whose rotational speed decreases in association with the upshifting of the automatic transmission 14 is predetermined. The end of the shift is determined when the following occurs. The shift end determination reference value NISCE is calculated based on the actual traveling state of the vehicle from the relationship stored in advance as shown in FIG.
That is, it is determined based on the vehicle speed V and the gear position. This relationship is experimentally obtained in advance so that the shift end period is determined at a time point that is traced back from the end point of the upshift shift by the response delay time of the engine rotation speed reduction suppressing control operation by the engine electronic control unit 76. It has been done. Since the time from the end-of-shift determination to the end of the shift is different for each gear, the relationship used is selected from a plurality of relationships stored in advance according to the actual gear. The end-of-shift determination reference value determined from the relationship selected when upshifting to the fourth speed is NISCE4, and determined from the relationship selected when upshifting to the fifth speed The determined shift end period reference value is NISCE5. During the upshift to the fourth gear (the gear ratio is 1), the clutch rotation speed N _C0 matches the output shaft rotation speed N _OUT at the end of the gear shift as shown by the broken line in FIG. A different relationship is required for the upshift to the fifth gear shown by the solid line in FIG. The shift end determination reference value NISCE4 is set in consideration of the fact that only the rotation change corresponding to the change width of the gear ratio occurs at the time of upshifting to the fourth speed gear.
The ISCE5 is set in consideration of the large rotation difference before and after the shift, because the rotating member (such as the clutch C0) is stopped during the upshift to the fifth gear. As shown in FIG. 9, the end-of-shift determination reference value NISCE is changed as the vehicle speed V increases.
This is because when the C valve 83 is opened wide, the time required to reach the target value becomes long. Further, the necessity of changing the end-of-shift determination reference value NISEC in accordance with the type of shift may increase or decrease the rotational change width of the rotary member (such as the input shaft 20) depending on the type of shift. This is because it is necessary to take into consideration the rate of rotation change and the width of rotation of the rotary member during gear shifting.

The opening SLUISC of the ISC valve 83 when the engine speed reduction suppression start control means 194 starts the operation of suppressing the decrease of the engine speed N _E is set in advance, for example, as shown in FIG. It is determined based on the actual traveling state of the vehicle, that is, based on the vehicle speed V and the gear stage G from the relationship described above. This relationship is because the ISC valve 83 is opened after the end-of-shift determination, so that the engine rotation speed N _E is the turbine rotation speed when the lock-up clutch 24 starts to be engaged at the completion of the shift for deceleration slip control. It is experimentally obtained in advance so that the speed is lower than the speed N _T by a predetermined value, for example, about several tens of revolutions which is a rotation speed equivalent to the target slip amount N _slip ^T. In the above relationship, the effect of suppressing the decrease in engine speed with respect to the constant opening degree θ _ISC is different for each gear, so that one selected according to the actual gear is used from a plurality of relationships stored in advance. . As a result, as shown in FIG. 10, the opening amount of the ISC valve 83 is increased as the vehicle speed V increases. This is because the difference between N _E and N _T tends to increase as the vehicle speed V increases, so the ISC valve 83 must be opened sufficiently in order to make the rotation difference between N _E and N _{T a} predetermined value. This is because it does not happen. In addition, even if N
_{Even if} the rotation difference between _E and N _T is the same, in order to make the rotation difference between N _E and N _{T a} predetermined value at high vehicle speed and low vehicle speed,
Higher vehicle speeds require the ISC valve 83 to be wide open.
Thus, the opening degree of the ISC valve 83 is determined in consideration of the easiness of setting the rotation difference between N _E and N _T to a predetermined value.

In the drive state determining means 200, the deceleration slip control means 192 starts the slip control during decelerating traveling, and the engine rotation speed reduction suppression start control means 194 starts the operation of suppressing the reduction of the engine rotation speed. After that, it is determined whether the vehicle is in a driving state, that is, a state in which the output torque of the engine is transmitted from the engine to the driving wheels (power-on state). The operation stopping means 202 is the driving state determining means 2 described above.
If it is determined by 00 that the vehicle is in the driving state, the engine rotation speed reduction suppressing operation by the engine rotation speed reduction suppressing means is stopped.

When the driving state judging means 200 judges that the vehicle is in the driving state, the learning correcting means 204 causes the engine rotation speed decrease suppressing means to start the ISC valve at the time of starting the slip control at the next deceleration running. 83
The control output to is corrected by learning. This learning correction is executed so that the driving state determination unit 200 does not determine that the vehicle is in the driving state.

Deceleration slip start control determination means 206
Determines whether or not the deceleration slip control start time control by the deceleration slip control means 192 is being executed, and if the deceleration slip control start time control is being executed,
The operation stopping means 202, the learning correcting means 204, and the engine rotation speed reduction suppression start control means 194 are allowed to operate, but if they are not being executed, those operations are prohibited.

FIG. 11 shows the main part of the control operation of the electronic shift control device 78, that is, the ISC at the start of deceleration slip control.
6 is a flowchart illustrating control of the opening degree of a valve 83.
In step SA1 shown in the figure (hereinafter, steps are omitted), it is determined whether or not a condition for starting the deceleration slip control executed by the deceleration slip control means 192 is satisfied. The starting condition is, for example, that the idle switch is turned on at a predetermined vehicle speed or higher. If the condition for starting the deceleration slip control is not satisfied, the determination at SA1 is negative, so SA
2, the ISC valve 83 is closed and SA3
After the content of the flag F1 is cleared to "0" in
This routine is ended. The flag F1 indicates that the engine rotation speed decrease suppression control has been started when the content is "1".

The deceleration slip control start condition is satisfied.
If the result of the determination in SA1 is affirmative, then SA4
In the off-up shift, that is, the accelerator pedal 50
Upshifts associated with the vehicle being inoperative
Is determined and executed by the shift control means 190.
Is determined. Accelerator pedal 50 is not operated
Before the coasting related to being in the working state has started
The deceleration slip control means 192 is used to reduce slippage during deceleration travel.
Even if the up control is started,
If not executed, deceleration without off-up shifting
Since the slip control has started, the deceleration slip
Engine speed N _EControl the decrease of
The same engine rotation speed reduction suppression control as the conventional
SA corresponding to the deceleration slip start control determination means 206
9 and below.

That is, it is determined at SA9 whether or not the starting control by the deceleration slip control means 192 is being executed. If the determination of SA9 is negative, SA2 and SA3 are executed. However, when the execution of the start-up control by the deceleration slip control means 192 is started, the determination at SA9 is affirmative, and therefore it is determined at SA10 whether or not the content of the flag F1 is "1". Initially, the judgment of SA10 is denied, so
At SA12, the opening degree SLUISC of the ISC valve 83 is calculated based on the actual vehicle speed V and the gear stage G from the prestored relationship shown in FIG.
Learning correction value α determined in the previous control at
Is subtracted from the opening SLUISC for learning correction, the content of the flag F1 is set to "1" in SA14, and the ISC valve 83 is opened in SA15 corresponding to the engine speed reduction suppression start control means 194. After only SLUISC is opened, this routine is ended. Then, once the content of the flag F1 is set to "1", the determination at SA10 is affirmative in the next control cycle. Therefore, at SA11, whether the vehicle is in the driving state or not, for example, the throttle valve opening TA It is judged based on the above. When the determination of SA11 is negative, the engine speed reduction suppression control is executed until the determination of SA9 is negative. However, if the determination at SA11 is affirmative, at SA16 the deceleration slip start control is ended, at SA17 a predetermined addition correction value Δα is added to the learning correction value α, and SA18 is set.
At S19, the ISC valve 83 is closed to end the engine speed reduction suppression control, and at SA19, the flag F is determined.
After the content of 1 is cleared to "0", this routine is ended.

Next, as shown at time t ₁ in FIG. 12, when the accelerator pedal 50 is returned to the non-operated state, the deceleration slip control and the off-up shift are associated with the deceleration slip control means 192 and the shift control means 190. The case of the above will be described. In such a case, S
Since the determinations at A1 and SA4 are both affirmative, it is determined at SA5 whether or not it is an upshift shift to the fifth speed (4 → 5 shift) in order to switch the shift end determination reference value NISCE. If the determination in SA5 is negative, it is determined in SA7 whether or not it is an upshift shift to the fourth gear (3 → 4 shift).
T _{2 in} FIG. 12 indicates this time point.

When the determination at SA5 is positive,
In SA6 corresponding to the shift end determination means 196, 4 → 5 stored in advance as shown in FIG. 9, for example,
Based on the relationship for gear shifting, the gear shift end determination reference value NISCE5 is determined based on the actual vehicle speed V, and it is determined whether the actual clutch rotational speed N _C0 is below the gear shift end determination reference value NISCE5. When the determination at SA6 is negative, SA2 and SA3 are executed, so that the engine speed reduction suppression control is not started.
If the determination of SA6 is affirmative, that is, the actual clutch rotation speed N _C0 is the end of shift determination reference value NISCE.
When the value is less than 5, the engine rotation speed reduction suppression control is started by executing SA9 and below. T _{3 in} FIG. 12 indicates this time point.

If the determination in SA7 is affirmative, in SA8 corresponding to the shift end determination means 196, the pre-stored 3 as shown in FIG. 9 is used.
→ From the relationship for four shifts, the shift end determination reference value NISCE4 is determined based on the actual vehicle speed V, and the rotation difference between the actual clutch rotational speed N _C0 and the output shaft rotational speed N _OUT (N _C0 −
It is determined whether N _OUT ) has fallen below the shift end determination reference value NISCE4. When the determination of SA7 or SA8 is negative, the engine speed reduction suppression control is not started by executing SA18 and SA19, but when the determination of SA8 is affirmative,
That is, when the rotation speed difference (N _C0 -N _OUT ) falls below the shift end period determination reference value NISCE3, the engine speed reduction suppression control is started by executing SA9 and below.

That is, since the determination at SA9 is affirmative at the beginning of the execution of the start-up control by the deceleration slip control means 192, it is determined at SA10 whether the content of the flag F1 is "1". . At the beginning, the decision of SA10 is denied, so at SA12,
The opening degree SLUISC of the ISC valve 83 is based on the relationship stored in advance in FIG.
Then, the learning correction value α determined in the previous control in SA13 is calculated based on the opening SLUISC.
Learning correction is performed by subtracting from the value of SA1, and the content of the flag F1 is set to "1" in SA14.
In, the ISC valve 83 is opened by the opening degree SLUISC, and then this routine is ended. Then, once the content of the flag F1 is set to "1", the determination at SA10 is affirmative in the next control cycle. Therefore, at SA11 corresponding to the drive state determination means 200, whether the vehicle is in the drive state or not. Is determined. When the determination of SA11 is negative, the engine speed reduction suppression control is executed until the determination of SA9 is negative. While the above steps are repeatedly executed, when the deceleration slip control start time control ends and the determination in SA9 is negative, SA2 and SA3 are executed and this routine is ended. T ₄ in FIG. 12 shows this state.

However, the judgment of SA11 is positive.
In the case of SA16, the control at the start of deceleration slip
Is finished, and the learning correction hand together with the SA13.
In SA17 corresponding to the step 204, the learning correction value α is set to
The constant addition correction value Δα is added, and the operation stopping means 20 is added.
At SA18 corresponding to 2, the ISC valve 83 is closed
Engine rotation speed reduction suppression control is stopped, and SA
The content of the flag F1 was cleared to "0" in 19
After that, this routine is ended. 13 t _FourTime is
This state is shown.

When the vehicle speed V is high and the turbine speed N _T is higher than the engine speed N _E , or when the vehicle speed V is low but the idle switch is not on, the idle switch is turned on and the slip control condition is satisfied. In the traveling state in which the condition is established, the determination of SA4 in FIG. 11 is denied and S
By executing A9 and below, the slip control is started and at the same time the SA 12 opens the ISC valve 83. This state is shown at time t _{1 in} FIG. At this time, I
When the SC valve 83 is opened, the engine speed N
_{Since E} exceeds the turbine rotation speed N _T , SA11
Since it is determined that the engine is in the driving state, the engine rotation speed reduction suppressing operation due to the opening of the ISC valve 83 is immediately stopped as shown at time t ₂ in FIG. When the determination of SA11 is affirmed in this way, the learning correction value α is updated to the side that is not determined to be the driving state in SA17 by executing SA16 and thereafter, so that the learning correction is performed in the next slip control. The opening degree of the ISC valve 83 is determined by the control output.

As described above, according to this embodiment, the SA corresponding to the engine rotation speed decrease suppression start control means 194.
The SA corresponding to the shift end determination means 196 by 15
6. Since the operation of suppressing the decrease in the engine speed is started when the end of the off-up shift is determined by SA8, the engine speed N _{E is set} after the accelerator pedal 50 is not operated. As compared with the case where the ISC valve 83 is opened by a predetermined amount in order to suppress the decrease of the engine, even if the off-up shift of the automatic transmission 14 is executed in association with the throttle valve 52 being fully closed, There is no delay in the reduction of the rotation speed, and the shift shock resulting therefrom can be preferably prevented. Further, as a result of the engine speed reduction suppression start control means 194 starting the operation for suppressing the decrease of the engine speed N _E from the time point t ₃ when the end of the shift is determined, the engine speed reduction suppression effect causes the engine speed to be reduced. N _E is turbine wheel 2
The slip control is substantially started by the deceleration slip control means 192 in the state of being approached to the rotation speed N _{T of} 2, so that the slip control becomes stable from the beginning and the discomfort is eliminated.

Further, according to the present embodiment, SA6 and SA8 corresponding to the shift end determination means 196 are the automatic transmission 14
The rotational speed N _{T of} the rotating member, that is, the rotational speed of the turbine impeller 22 of the torque converter 12 that decreases in relation to the off-up shift of the predetermined shift end determination reference value NI.
The end of the shift is determined when the value becomes equal to or less than SCE, and the end-of-shift determination reference value NISCE is determined based on the actual traveling state of the vehicle from the preset relationship shown in FIG. 9, for example. Since the relationship is experimentally obtained in advance such that the engine rotation speed decrease suppressing means and the like delay the response delay time from the shift end time point, the shift end period determining means 196 ends up in the shift end time. Since the end of the shift is determined when the response delay time D of the engine speed control device goes back from the time point, the delay of the decrease of the engine speed N _E is made as small as possible and is sure at the start of the slip control. In addition, there is an advantage that an effect of suppressing a decrease in engine speed is generated.

Further, according to this embodiment, the ISC valve 83 provided in parallel with the throttle valve 52 for adjusting the idle rotation speed of the engine 10 and the electronic control unit for engine 76 for driving and controlling the ISC valve 83 are provided. The ISC valve 83 functions as an idle rotation speed reduction suppressing unit, and when the engine rotation speed reduction suppression start control unit 194 starts the operation for suppressing the reduction of the engine rotation speed.
The opening degree SLUISC of is determined based on the actual traveling state of the vehicle from the preset relationship shown in FIG. 10, for example. This relationship is such that when the slip control is started by the deceleration slip control means 192, the target slip amount N
Preliminary experiments were performed to determine the opening SLUISC of the ISC valve 83 so that _slip ^T is substantially formed, in other words, the engine speed N _E and the rotation speed N _T of the turbine impeller 22 are substantially matched. Because it was sought after,
After all, at the time of ending the shift, that is, at the time of starting the deceleration slip control, there is an advantage that the engine speed N _E and the rotation speed N _T of the turbine impeller 22 are substantially matched and the slip control is smoothly started.

[0057] Further, according to this embodiment, when the vehicle by SA11 corresponding to the driving state determining means 200 is determined to become the driving state, t ₄ in FIG. 13 by SA18 corresponding to the operation stop means 202 As shown at the time point, the operation of the engine speed reduction suppressing means is stopped. Therefore, the engine rotation speed decrease suppressing operation by the engine rotation speed decrease suppressing means is canceled and the increasing tendency of the engine rotation speed N _{E from} the original value is canceled, so that the engine rotation speed N _E is the turbine impeller 22. The deceleration slip control below the rotation speed N _T of the engine is stably continued, and the discomfort caused by the engine speed N _E exceeding the rotation speed N _T of the turbine impeller 22 is eliminated.

Further, according to the present embodiment, when it is determined by SA11 corresponding to the drive state determination means 200 that the vehicle is in the drive state, the engine rotation speed decrease suppressing means is started at the start of the next slip control. To IS
The control output to the C valve 83 is supplied to the drive state determination means 200.
Accordingly, SA13 and SA17 corresponding to the learning correction unit 204 that performs learning correction to the side where it is not determined that the vehicle has been driven are further provided. By doing so, there is an advantage that the vehicle is preferably prevented from being driven at the start of the next deceleration slip.

Incidentally, FIG. 15 shows a case where the deceleration slip control of the vehicle and the control for suppressing the decrease of the engine speed N _E by opening the ISC valve 83 from the start of the off-up shift are executed. In this case, when the accelerator pedal 50 is in the non-operated state, the engine rotation speed of the vehicle that has been in the driving state does not suddenly decrease, and the decrease speed of the engine rotation speed is suppressed. The slip control can be stably started as compared with the case where the reduction of the rotation speed is left as it is. However, the upshift shift of the automatic transmission ( (Off-up shift) is executed, the engine output torque is increased during the shift due to the opening of the ISC valve 83, the decrease in the engine rotation speed is delayed, and the drive torque at the end of the shift varies. Then, there was an inconvenience that a shift shock occurred. Further, FIG. 16 shows the ISC at the end of the upshift shift (off-up shift) of the automatic transmission.
The case where the valve 83 is opened is shown. In this case, the idle rotation speed control device (engine electronic control device 76
And ISC valve 83) delays the response, resulting in ISC valve 83
The engine rotation speed N _E temporarily drops during the period until the effect of opening the engine occurs. Note that the fuel cut control is executed after the end of the engine rotation speed reduction suppression control, that is, after t ₄ in FIGS. 12, 13, 15, and 16 or t ₃ in FIG.

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

For example, in the above-described embodiment, the input shaft rotation speed N _IN of the automatic transmission 14, that is, the turbine impeller 2
The turbine rotation speed sensor 75 that detects the input shaft rotation speed N _IN of the automatic transmission 14 substantially by detecting the rotation speed N _{T of} 2 or the rotation speed (clutch rotation speed) N _CO of the clutch drum of the clutch C0. Although used, the input shaft rotational speed N _IN is calculated by multiplying the output shaft rotational speed N _OUT of the automatic transmission 14 detected by the vehicle speed sensor 66 by the gear ratio i _G at that time. May be.

Further, in the above-described embodiment, the ISC valve 83 is opened, so that the engine 1 at the start of deceleration of the vehicle is started.
Although the decrease rate of the rotation speed of 0 was suppressed, by injecting a predetermined amount of fuel from the fuel injection valve 80,
The reduction in the rotation speed of the engine 10 at the start of deceleration traveling of the vehicle may be suppressed.

Further, in FIG. 11 of the above-mentioned embodiment, the forward movement 5
Although the control contents of the fourth speed and the fifth speed of the automatic transmission 14 of the third gear are described, when the actual clutch rotational speed N _CO is lower than the end-of-shift determination reference value NISCE3 for the third speed as well. Alternatively, the engine rotation speed decrease suppression control may be executed as in the case of the fourth speed or the fifth speed.

Further, although the automatic transmission 14 having five forward gears is used in the above-described embodiment, for example, Toyota AS40
An automatic transmission with four forward gears such as an E automatic transmission may be used. In this case, the rotating member (clutch C0) capable of detecting rotation is
At the time of shifting to the third speed, the gear ratio changes so as to rotate the same as the output shaft 42 at the gear ratio 1, and at the fourth speed, the rotation of the clutch C0 becomes zero. Therefore, the SA5 of FIG. This can be dealt with by setting the shift determination step to the speed stage and SA7 as the shift determination step to the third speed.

Further, in the above-described embodiment, the control of the ISC valve 83 is executed by the electronic control unit for engine 76, but it is executed by the electronic control unit for shifting 78 by mutually transmitting the input signal or the output signal. May be done.

Further, in SA11 of the above-described embodiment, the driving state of the vehicle is judged based on the throttle valve opening degree TA, but it may be judged based on the off state of the idle switch, or deceleration slip occurs. The drive state of the vehicle may be determined based on the positive / negative or magnitude of the slip amount of the lockup clutch 24 at the start.

Although not specifically exemplified, the present invention can be implemented in various modified and improved modes based on the knowledge of those skilled in the art.

[Brief description of drawings]

FIG. 1 is a skeleton diagram illustrating a configuration of an automatic transmission for a vehicle in which a lockup clutch is controlled by a control device according to an embodiment of the present invention.

FIG. 2 is a table showing a relationship between a combination of operations of a plurality of frictional engagement devices and a gear established by the combination in the automatic transmission of FIG. 1;

FIG. 3 is a block diagram including a hydraulic control circuit and an electric control circuit for controlling the automatic transmission of FIG. 1;

FIG. 4 is a diagram showing a lockup clutch release region, a slip control region, and an engagement region in the embodiment of FIG. 3 respectively.

5 is a diagram illustrating a main part of the hydraulic control circuit of FIG.

FIG. 6 is a diagram illustrating output characteristics of the linear solenoid valve of FIG.

7 is a characteristic diagram showing a relationship between a control pressure P _SLU and an engagement-side hydraulic pressure P _on and a release-side hydraulic pressure P _off of a lock-up clutch in the hydraulic control circuit of FIG. 5;

8 is a functional block diagram for explaining a main part of a control function of the shift electronic control device of FIG. 3;

9 is a diagram showing a relationship used to determine a shift change end determination reference value NICE in FIG. 8. FIG.

10 is a diagram showing a relationship used to determine the opening degree SLUISC of the ISC valve in FIG.

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

FIG. 12 is a time chart explaining the control operation of FIG. 11.

FIG. 13 is a time chart for explaining the control operation of FIG. 11, showing a case where the vehicle is driven by opening the ISC valve.

FIG. 14 is a time chart for explaining the control operation of FIG. 11, showing a case where the vehicle is in a driving state at the start of deceleration slip control without upshift gear shifting.

FIG. 15 is a time chart for explaining the operation of the conventional control device, showing a case where the ISC valve is opened after the accelerator pedal is brought into a non-operated state.

FIG. 16 is a time chart for explaining the operation of the conventional control device, in which I is calculated from the completion point of the off-up gear shift that occurs in association with the accelerator pedal being in the non-operated state.
It shows the case where the SC valve is opened.

[Explanation of symbols]

10: engine 14: automatic transmission 24: lockup clutch 76: engine electronic control unit (engine rotation speed reduction suppressing means) 83: ISC valve (idle rotation speed control valve) 192: deceleration slip control means 194: engine rotation speed Decrease suppression start control means 196: Gear shift end determination means 200: Drive state determination means 202: Operation stop means 204: Learning correction means

Claims (5)

[Claims] 1. A vehicle having a direct coupling clutch that directly couples a pump impeller and a turbine impeller of a fluid transmission, and an automatic transmission that automatically shifts to any one of a plurality of gear stages. Control provided with deceleration slip control means for executing slip control of the direct-coupling clutch when the vehicle is decelerating, and engine rotation speed decrease suppressing means for suppressing decrease in engine rotation speed at the start of slip control by the deceleration slip control means. A shift end period determining means for determining whether or not an upshift shift of the automatic transmission executed in association with a non-operation of the accelerator pedal has reached a predetermined shift end period; The engine rotation for starting the operation of the engine rotation speed decrease suppressing means from the time when the end of the shift of the automatic transmission is judged by the end judging means. A control device for a vehicle lockup clutch, characterized in that it comprises a time suppressing reduction start control means. 2. The control device for a direct coupling clutch for a vehicle according to claim 1, wherein the shift change end determination means is determined based on an actual traveling state of the vehicle from a preset relationship. 3. The engine rotation speed reduction suppressing means is
2. The control device for a direct coupling clutch for a vehicle according to claim 1, wherein the control output for suppressing a decrease in the engine rotation speed is changed based on an actual traveling state of the vehicle based on a preset relationship. 4. A vehicle having a direct coupling clutch that directly couples a pump impeller and a turbine impeller of a fluid transmission, and an automatic transmission that automatically shifts to any of a plurality of gear stages, the vehicle comprising: Control device including deceleration slip control means for executing slip control of the direct coupling clutch during deceleration traveling, and engine rotation speed reduction suppressing means for suppressing decrease in engine rotation speed at the start of slip control by the deceleration slip control means. A drive state determining means for determining whether or not the vehicle is in a drive state when the engine rotational speed reduction suppressing means is suppressing the decrease in the engine rotational speed, and the drive state determining means for controlling the vehicle Includes an operation stopping means for stopping the operation of the engine rotation speed reduction suppressing means when it is determined that the engine has been driven. DOO control device for a vehicular lockup clutch according to claim. 5. The learning correction means for learning-correcting the control output from the engine rotation speed decrease suppressing means at the time of the next slip control when the driving state determining means determines that the vehicle is in the driving state. The control device for a direct coupling clutch for a vehicle according to claim 4, which is included.