JPH11310060A - Slip control device for automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of a shock caused when driving force is lost by providing a control means starting the deceleration fuel cut control when the fuel cut prohibition time elapses after an idle control valve is closed. SOLUTION: After the preparation for slip control is completed and a lockup clutch 24 is coupled in the half-coupled state, an idle control valve 66 is closed, and deceleration fuel cut control is started to stop a fuel feed to an internal combustion engine 2. The slip control device 52 of an automatic transmission 2 sets the fuel cut prohibition time t1 during the period until the deceleration fuel cut control is started after the idle control valve 66 is closed by a control device 54 and starts the deceleration fuel cut control when the fuel cut prohibition time t1 elapses after the idle control valve 66 is closed. The occurrence of a shock caused by the abrupt reduction of the engine speed when the lockup clutch 24 is coupled can be decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slip control device for an automatic transmission, and more particularly to a slip control during a deceleration operation, which can reduce a shock when a lock-up clutch is engaged in a half-engaged state. The present invention relates to a slip control device for an automatic transmission, which can reduce shock when starting deceleration fuel cut control during deceleration operation and reduce shock when performing shift control during execution of slip control during deceleration operation. .

[0002]

2. Description of the Related Art Some internal combustion engines mounted on vehicles are connected to an automatic transmission having a torque converter and an auxiliary transmission mechanism. An automatic transmission including a torque converter transmits power via a working fluid between a pump impeller and a turbine runner, which are input / output elements of the torque converter, so that slip occurs due to relative rotation between the input / output elements.

For this reason, an automatic transmission having a torque converter can smoothly transmit power due to a function of absorbing torque fluctuation due to slip, but has a problem that power transmitted by slip causes loss.

Therefore, some automatic transmissions are provided with a lock-up clutch for engaging and disengaging input / output elements of the torque converter, and a slip control device for adjusting the slip of the torque converter by the lock-up clutch. is there.

Some internal combustion engines stop fuel supply during deceleration operation. Such a slip control device of an automatic transmission connected to an internal combustion engine executes a slip control for engaging a lock-up clutch in a semi-engaged state so as to limit a slip of the torque converter during a deceleration operation of the internal combustion engine. .

FIGS. 9 to 11 show such a slip control device for an automatic transmission. This automatic transmission includes a torque converter and an auxiliary transmission mechanism, and a torque converter is provided with a lock-up clutch for adjusting slip. Further, the internal combustion engine connected to the automatic transmission is provided with an idle control valve for controlling an idle air amount in an idle intake passage which bypasses the throttle valve and communicates with the intake passage, and a fuel supply means for adjusting a supply fuel. Provided.

The slip control device for an automatic transmission has, as control means, an engine control unit for controlling the internal combustion engine and a transmission control unit for controlling the automatic transmission. The throttle control is transmitted from the engine control unit to the transmission control unit. A degree signal and a water temperature signal are sent, and a first slip control signal and a second slip control signal are sent from the transmission control unit to the engine control unit. The slip control device controls the lock-up clutch, the idle control valve, and the fuel supply means during the deceleration operation as shown in FIGS. 9 to 11 based on these signals.

As shown in FIG. 9, the slip control device of the automatic transmission starts control (step 200).
It is determined whether a deceleration fuel cut condition in which the throttle valve is fully closed and the engine speed is equal to or higher than the fuel cut speed is satisfied (step 202).

When the determination (step 202) is YES, the idle control valve is turned on and opened by the engine control unit so as to increase the intake air amount, and the slip control first and second signals are transmitted by the transmission control unit. SC1, SC2
Is turned on to prepare for slip control for engaging the lock-up clutch in a semi-engaged state so as to limit the slip of the torque converter (step 204), and the transmission control unit completes preparation for slip control and locks. It is determined whether or not the up clutch has been engaged in a semi-engaged state (step 206).

If this determination (step 206) is YES, the transmission control unit controls the slip control second signal SC.
Then, the idle control valve is turned off and closed by the engine control unit, and the deceleration fuel cut control is started to stop the fuel supply by the fuel supply means (step 208).

During the deceleration fuel cut control, the engine control unit determines whether or not the engine speed is equal to or lower than the fuel return speed and the deceleration fuel cut return condition is satisfied (step 210). If this determination (step 210) is YES, the shift control unit turns off the first slip control signal SC1 to release the slip control, and ends the deceleration fuel cut control by the engine control unit (step 21).
2), end (step 214).

As described above, when the deceleration fuel cut control is immediately performed during the deceleration operation, the slip control device of the automatic transmission causes the lock-up clutch that has been completely engaged (locked up) to fully close the throttle valve. As a result, there is a disadvantage that the engine speed rapidly drops and the deceleration fuel cut return condition is satisfied at an early stage and the fuel saving effect is impaired. In this case, the decrease in the engine speed is moderated to extend the fuel cut period.

However, during deceleration operation, a sudden decrease in the engine speed makes it impossible to secure the hydraulic pressure required for slip control of the automatic transmission, as shown in FIG.
Even if the deceleration fuel cut condition is satisfied, the deceleration fuel cut is not immediately executed, the idle control valve is opened to increase the intake air amount by the bypass air amount, and the engine speed is maintained so as not to drop rapidly.

The slip control device of the automatic transmission starts the slip control while the engine speed is maintained,
After the preparation for slip control is completed and the lock-up clutch is engaged in a semi-engaged state, the idle control valve is closed to return the intake air amount to the original value, and the deceleration fuel cut control is started. In the deceleration fuel cut control, when the deceleration fuel cut return condition is satisfied, the slip control is released and the deceleration fuel cut control ends.

Japanese Patent Application Laid-Open No. 61-99763 and Japanese Patent Application Laid-Open No.
There are those disclosed in JP-A-118265 and JP-A-7-71594.

Japanese Unexamined Patent Publication No. 61-99763 discloses that a lock-up clutch is feed-forward controlled by a signal corresponding to a set slip amount of a torque converter during a set time after releasing an accelerator pedal, and The feedback control of the lock-up clutch is performed so that the torque converter reaches the target slip amount until the release of the accelerator pedal is stopped after the lapse.

The control device disclosed in Japanese Patent Application Laid-Open No. 2-118265 discloses a control device for engaging a lock-up clutch of a torque converter during deceleration fuel cut.
When shifting to deceleration fuel cut and lock-up clutch engagement control, fuel cut is executed after a delay time for lock-up clutch engagement elapses.

Japanese Patent Laying-Open No. 7-71594 discloses a control device for starting a slip control of a lock-up clutch of a torque converter prior to a fuel cut when a coasting of a vehicle is started. At this time, the control amount of the slip control is changed to the side where the slip amount decreases during the period until the negative rate of change of the engine speed reaches zero.

[0019]

In the conventional slip control device for an automatic transmission, the slip control and the deceleration fuel cut control are performed as shown in FIGS. 9 to 11 during the deceleration operation of the internal combustion engine. .

The slip control device temporarily releases the lock-up clutch in the fully engaged state (lock-up state) by fully closing the throttle valve during the deceleration operation of the internal combustion engine.
Start preparing for slip control to engage in the semi-engaged state,
After the preparation for the slip control is completed and the lock-up clutch is engaged in a semi-engaged state, the deceleration fuel cut control is started.

However, the conventional slip control device has a disadvantage that when the preparation for the slip control is completed and the lock-up clutch is engaged in a half-engaged state, the engine speed drops rapidly and a shock is generated. Yes (A in FIG. 10), and there is an inconvenience that the driving force generated by the internal combustion engine is lost due to the stop of the supplied fuel when the deceleration fuel cut control is started (B in FIG. 10).

[0022]

SUMMARY OF THE INVENTION Therefore, in order to eliminate the above-mentioned disadvantages, the present invention reduces the amount of idle air in an idle intake passage which bypasses a throttle valve of an internal combustion engine mounted on a vehicle and communicates with the intake passage. An idle control valve for controlling the engine; a lock-up clutch for adjusting a slip of a torque converter of the automatic transmission connected to the internal combustion engine; and increasing an intake air amount of the internal combustion engine during a deceleration operation of the internal combustion engine. Preparation of slip control for engaging the lock-up clutch in a half-engaged state so as to limit the slip of the torque converter while opening the idle control valve is started. After the up-clutch is engaged in the half-engaged state, the idle control valve is closed and the fuel to the internal combustion engine is reduced. In a slip control device for an automatic transmission that starts deceleration fuel cut control so as to stop supply, a fuel cut prohibition time is set from the time when the idle control valve is closed to the time when the deceleration fuel cut control is started. And a control means for starting the deceleration fuel cut control after the fuel cut prohibition time has elapsed from the time when the idle control valve is closed.

The control means executes ignition timing retard control so as to retard the ignition timing before the deceleration fuel cut control is started during the lapse of the fuel cut inhibition time. The control means sets and provides an ignition timing delay time between the time when the idle control valve is closed and the time when the ignition timing delay control is started, and sets the ignition timing delay time from when the idle control valve is closed. A control means for starting the ignition timing retard control after the ignition timing delay time has elapsed.

The control means is a control means for starting a shift control during the execution of the ignition timing retard control when a shift control of the auxiliary transmission mechanism of the automatic transmission is performed during the execution of the slip control. The control means sets and provides an idle control valve opening delay time from the time when the deceleration operation of the internal combustion engine is started to the time when the idle control valve is opened, and the automatic control is performed during execution of the slip control. A control means for opening the aisle control valve after elapse of the idle control valve opening delay time from the time when the deceleration operation of the internal combustion engine is started when the shift control of the auxiliary transmission mechanism of the transmission is involved. And

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A slip control device according to the present invention
After the preparation of the slip control is completed by the control means and the lock-up clutch is engaged in the half-engaged state, the fuel is supplied between the time when the idle control valve is closed and the time when the deceleration fuel cut control is started. Set the cut prohibition time and set it, and start the deceleration fuel cut control after the fuel cut prohibition time elapses from the time when the idle control valve is closed. Therefore, the occurrence of a shock due to a sudden decrease in the engine speed when the lock-up clutch is engaged can be reduced, and a shock due to a sudden decrease in the engine speed due to the stop of fuel can be reduced. Occurrence can be reduced.

In the slip control device, the control means executes the ignition timing retard control so as to retard the ignition timing before the deceleration fuel cut control is started during the lapse of the fuel cut prohibition time, Before starting the deceleration fuel cut control, the engine speed reduced by the closing operation of the idle control valve is further reduced by the ignition timing retard control to further reduce the occurrence of a shock when the deceleration fuel cut control is started. be able to. In this case, the slip control device is provided with an ignition timing delay time set by the control means between the time when the idle control valve is closed and the time when the ignition timing retard control is started, and the idle control valve By starting the ignition timing delay control after the ignition timing delay time has elapsed from the time when the valve was closed, there is an ignition timing delay time until the engine speed is reduced by the retardation of the ignition timing, Shock reduction when the deceleration fuel cut control is started can be realized by stepwise control.

Further, in the slip control device, the control means starts the shift control during the execution of the ignition timing retard control when the shift control of the auxiliary transmission mechanism of the automatic transmission is accompanied during the execution of the slip control. Thus, the shift control can be executed in a state where the related rotation speed is reduced by the ignition timing retard control, so that the occurrence of a shock due to the shift can be reduced. In the slip control device, the control means sets and provides an idle control valve opening delay time from when the deceleration operation of the internal combustion engine is started to when the idle control valve is opened. When the shift control of the auxiliary transmission mechanism of the automatic transmission is accompanied by the opening of the idle control valve after a lapse of the idle control valve opening delay time from the start of the deceleration operation of the internal combustion engine, the ignition timing retard control is performed. Since the shift control can be reliably executed during the shift, the occurrence of a shock due to the shift can be more reliably reduced.

[0028]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 5 show a first embodiment of the present invention. In FIG. 4, reference numeral 2 denotes an internal combustion engine mounted on a vehicle (not shown), and reference numeral 4 denotes an automatic transmission. Automatic transmission 4
As shown in FIG. 5, an input shaft 8, an intermediate shaft 10, and an output shaft 12 are provided in a transmission case 6 so as to be pivotally supported, and a torque converter 14 and an auxiliary transmission mechanism 16 are provided.

The torque converter 14 is provided with a pump section 18 as an input element and a turbine section 20 as an output element so as to be relatively rotatable, and a stator rotatable only in a specific direction between the pump section 18 and the turbine section 20. A lock-up clutch 24 for adjusting slip of the pump section 18 and the turbine section 20 is provided by providing the section 22.

The pump section 18 includes a pump impeller 25.
Is held by an impeller holding member 26, and the impeller holding member 26 is connected to a crankshaft 30 of the internal combustion engine 2 via a cover member 28. The turbine section 20 holds the turbine runner 32 with a runner holding member 34,
The runner holding member 34 is connected to the input shaft 8. The stator portion 22 holds a stator blade 36 by a blade holding member 38, and the blade holding member 38 is supported by the input shaft 8 so as to be rotatable only in a specific direction by a one-way clutch 40. The lock-up clutch 24
Is provided with a clutch section 42 for engaging and disengaging the impeller holding member 26 of the pump section 18 and the runner holding member 34 of the turbine section 20.

The auxiliary transmission mechanism 16 comprises a planetary gear provided between the input shaft 8, the intermediate shaft 10, and the output shaft 12 and the like, and the meshing state is switched by a switching mechanism 44 comprising a clutch, a brake and the like. . Output shaft 1
Numeral 0 is connected to driving wheels via a propulsion shaft or the like (not shown).

The automatic transmission 4 includes an auxiliary transmission mechanism 16.
And an oil pan 48 is provided so as to cover the valve body 46. The oil in the oil pan 48 is pressure-fed to the valve body 46 by an oil pump 50, and locked up with the switching mechanism 44 of the torque converter 14 and the auxiliary transmission mechanism 16 by a hydraulic control valve (not shown) built in the valve body 46. It is supplied to and discharged from the clutch part 42 of the clutch 24,
Transmission control of the auxiliary transmission mechanism 16 and the lock-up clutch 2
4 is performed.

The slip control device 52 of the automatic transmission 4
As shown in FIG. 4, the control means 54 includes an engine control unit 56 for controlling the internal combustion engine 2 and a transmission control unit 58 for controlling the automatic transmission 4.

The engine control unit 56 includes a throttle opening sensor 60 for detecting a throttle opening of a throttle valve (not shown) of the internal combustion engine 2 and a water temperature sensor 62 for detecting a cooling water temperature of the internal combustion engine 2. , And an engine speed sensor 64 for detecting the engine speed of the internal combustion engine 2. The engine control unit 56 includes an idle control valve 66 that controls the amount of idle air in an idle intake passage that bypasses a throttle valve (not shown) and communicates with the intake passage, and a fuel supply that adjusts fuel supplied to the internal combustion engine 2. The means 68 and the ignition timing adjusting means 70 for adjusting the ignition timing of the internal combustion engine 2 are connected.

The transmission control unit 58 includes the engine speed sensor 64, an input shaft speed sensor 72 for detecting the input shaft speed of the input shaft 8, and a hydraulic control valve (not shown) of the valve body 46. ) Is connected to a solenoid valve 74 for a shift solenoid for shifting control by switching operation and a solenoid valve 76 for a lock-up clutch for slip control of the lock-up clutch 24.

The slip control unit 52 sends a throttle opening signal and a water temperature signal from the engine control unit 56 of the control means 54 to the transmission control unit 58, and the slip control first signal is transmitted from the transmission control unit 58 to the engine control unit 56. The signal SC1 and the slip control second signal SC2 are sent. The slip control device 52 controls the lock-up clutch 24, the idle control valve 66, the fuel supply means 68, and the ignition timing adjustment means 70 during the deceleration operation as shown in FIGS. I do.

The slip control device 52 is provided with an idle control valve 66 that controls the amount of idle air in an idle intake passage that bypasses a throttle valve (not shown) of the internal combustion engine 2 and communicates with the intake passage. Automatic transmission 4
A lock-up clutch 24 for adjusting the slip of the torque converter 14 is provided, and the control means 54 opens the idle control valve 66 so as to increase the intake air amount of the internal combustion engine 2 during the deceleration operation of the internal combustion engine 2 and the torque converter. Preparation for slip control for engaging the lock-up clutch 24 in a semi-engaged state to limit slippage of the lock-up clutch 24 is started. After that, the idle control valve 66 is closed and the deceleration fuel cut control is started so as to stop the fuel supply to the internal combustion engine 2.

The slip control device 52 of the automatic transmission 2
As shown in FIG. 3, the fuel cut prohibition time t1 is set and provided by the control means 54 between the time when the idle control valve 66 is closed and the time when the deceleration fuel cut control is started. The deceleration fuel cut control is started after the fuel cut prohibition time t1 has elapsed from the time when the valve was closed.

The control means 54 of the slip control device 52
Executes the ignition timing retard control so as to retard the ignition timing before the deceleration fuel cut control is started during the lapse of the fuel cut prohibition time t1. In this case, the control means 5
4, the ignition timing delay time t2 is set and provided between the time when the idle control valve 66 is closed and the time when the ignition timing retard control is started, as shown in FIG. 3, and the idle control valve 66 is closed. The ignition timing retard control is started after the ignition timing delay time t2 has elapsed from the time of the movement.

The slip control device 52 generates a slip control first signal SC1 sent from the transmission control unit 58 to the engine control unit 56 during a period from the start of the deceleration operation to the execution of the fuel cut control. Second signal SC
By performing the slip control according to the state (STATE) in a plurality of stages, the shock when the lock-up clutch 24 is engaged in the half-engaged state and the shock when the fuel cut control is started are reduced. Reduce.

As shown in FIG. 2, the state is changed from the first state (STATE = 1) to the fifth state (RSTATE = 5) by a combination of ON / OFF of the first and second slip control signals SC1 and SC2. Is set.

When the first slip control signal SC1 and the second slip control signal SC2 are both off and in the 0th state (STAT
In the case of E = 0), the fuel is normally supplied without performing the fuel cut control, and the slip control is not performed.

When the slip control first signal SC1 is off and the slip control second signal SC2 is on, the first state (STAT)
If E = 1), the fuel cut control is prohibited and the first process of the slip control is performed. The first process is a process in a case where a shift control is performed during execution of the slip control as in a second embodiment to be described later, and is performed between the time when the deceleration operation is started and the time when the idle control valve 64 is opened. The opening delay time t3 is set, and preparation for slip control is started.

When the slip control first signal SC1 and the slip control second signal SC2 are both on, the second state (STAT)
In the case of E = 2), the fuel cut control is prohibited and the second process of the slip control is performed. The second process is a process for securing the oil pressure by gradually decreasing the engine speed, and opening the idle control valve 66 to increase the intake air amount by the idle air amount.

When the slip control first signal SC1 is off and the slip control second signal SC2 is on, the third state (STAT)
In the case of E = 3), the fuel cut control is prohibited and the third process of the slip control is performed. In the third process, the torque of the internal combustion engine 2 is increased as a result of increasing the intake air amount by opening the idle control valve 66, which causes a shock when the fuel cut control is started. This is a process for reducing the torque increased during the half-engagement, and the increased intake air amount is returned to the original intake air amount by closing the idle control valve 64 and stopping the supply of the idle air amount. .

When the slip control first signal SC1 and the slip control second signal SC2 are both on, the fourth state (STAT)
In the case of E = 4), the fuel cut control is prohibited and the fourth process of the slip control is performed. The fourth process is a process for further reducing the shock at the time of the fuel cut control or the shift control by reducing the torque of the internal combustion engine 2, and delaying the ignition timing after the ignition timing delay time t2 has elapsed. Let it.

When the slip control first signal SC1 is on and the slip control second signal SC2 is off, the fifth state (STAT)
In the case of E = 4), after the fuel cut inhibition time t1 has elapsed, the fuel cut control is executed and the slip control is released.

Next, the operation of the first embodiment will be described with reference to FIGS.

The slip control device 50 of the automatic transmission 2
As shown in FIG. 1, when the control starts (step 10).
0), the slip control second signal SC by the control means 52
It is determined whether or not 2 is on (step 102).
If this determination (step 102) is NO, it is determined whether the first slip control signal SC1 is on (step 104).

If the determination (step 104) is NO, the fuel injection control and the slip control are not performed (step 106) and the end (step 108) is set as the zero state (STATE = 0).

When the throttle valve is fully closed and the engine speed is equal to or higher than the fuel cut speed and the deceleration fuel cut condition is satisfied, if the determination (step 102) is YES, the slip control first signal SC1 is turned on. It is determined whether or not there is (Step 110).

If this determination (step 110) is NO, it is determined whether STATE ≧ 2 (step 112). If this determination (step 112) is NO, the first process is performed with the first state (STATE = 1) (step 114), and the process ends (step 108).

The first process (step 114) is a process when the slip control is accompanied by a shift control as in a second embodiment to be described later. This first processing is performed from the fourth state (STATE = 4) to the fifth state (ST
A second state (STATE = 2) from the fully closed state of the throttle valve in order to perform the shift control near ATE = 5)
This is a process for arbitrarily adjusting the time until the subsequent process is started.

In the first process (step 114), preparation for slip control is started. In the first embodiment that does not involve the shift control, the time of the first process can be set to a very short time only for starting the preparation for the slip control. When the shift control is not performed, the time for the first process can be omitted. In this case, the preparation for the slip control is started simultaneously with the start of the second process described later.

If the first processing (step 114) is completed and the judgment (step 110) is YES, the STAT
It is determined whether or not E ≧ 3 (step 116). If this determination (step 116) is NO, the second
The second process is performed with the state (STATE = 2) (step 118), and the process ends (step 108).

The second process (step 118) is a process for opening the idle control valve 66 to increase the intake air amount by the idle air amount. The second process is a process for gently reducing the engine speed and securing the hydraulic pressure.
When the engine speed substantially matches the input shaft speed and the duty value of the lock-up clutch 24 reaches a target value that enables the semi-engaged state, preparation for slip control is completed and the lock-up clutch 24 is half-engaged. The operation is terminated when engaged in the combined state.

If the second processing (step 118) is completed and the judgment (step 112) is YES, the third processing
The third processing is performed with the state (STATE = 3) (step 120), and the processing ends (step 108).

The third process (step 120) is a process for decreasing the torque that has increased during the half engagement of the lock-up clutch 24. The idle control valve 66 is closed to stop the supply of the idle air amount. Then, the increased intake air amount is returned to the original intake air amount.

If the third processing (step 120) is completed and the judgment (step 116) is YES, the fourth processing
The fourth process is performed with the state (STATE = 4) (step 122), and the process ends (step 108).

The fourth process (step 122) is a process after the lapse of the ignition timing delay time t2 from the time when the idle control valve 66 is closed, and the ignition timing for delaying the ignition timing by the ignition timing adjusting means 70. Performs retard control.

If the fourth processing (step 122) is completed and the judgment (step 104) is YES, the fifth processing
The fifth process is performed with the state (STATE = 5) (step 124), and the process ends (step 108).

The fifth process (step 124) is a period from the time when the idle control valve 66 is closed to the fuel cut inhibition time t.
This is a process after 1 has elapsed, in which the fuel supply means 68 executes the fuel cut control and releases the slip control.

Since the fuel cut control is executed in the fifth process in which the engine speed is kept low (the torque is low) after the first to fourth processes of the slip control are completed, a shock is generated. Can be reduced.

As described above, the slip control device 52
Is the time from when the idle control valve 66 is closed to when the deceleration fuel cut control is started after the preparation for the slip control is completed and the lock-up clutch 24 is engaged in the half-engaged state. By setting a cut prohibition time t1 and starting the deceleration fuel cut control after the fuel cut prohibition time t1 has elapsed from the time when the idle control valve 66 is closed, the deceleration fuel cut is started simultaneously with the completion of the slip control preparation. Since the control is not started, it is possible to reduce the occurrence of a shock due to a sudden decrease in the engine speed when the lock-up clutch 24 is engaged, and to reduce the sudden increase in the engine speed due to the stop of the fuel. The occurrence of shock due to the decrease can be reduced.

The slip control device 52 executes the ignition timing retard control so as to retard the ignition timing before the deceleration fuel cut control is started during the lapse of the fuel cut prohibition time t1. Before starting the deceleration fuel cut control, the engine speed reduced by the closing operation of the idle control valve 66 is further reduced by the ignition timing retard control to further reduce the occurrence of a shock when the deceleration fuel cut control is started. can do.

In this case, the slip control device 52
Is the ignition timing delay time t between the time when the idle control valve 66 is closed and the time when the ignition timing retard control is started.
2, the ignition timing delay control is started after the ignition timing delay time t2 has elapsed from the time when the idle control valve 66 is closed, so that the engine speed is reduced due to the ignition timing delay. Until the ignition timing delay time t2
Therefore, the reduction of shock when the deceleration fuel cut control is started can be realized by stepwise control.

FIG. 6 shows a second embodiment of the present invention. The slip control device 52 of the second embodiment is provided with the internal combustion engine 2 and the automatic transmission 4 shown in FIGS. The slip control device 52 of the second embodiment is controlled by
The fuel cut inhibition time t1 between the time when the idle control valve 66 is closed and the time when the deceleration fuel cut control is started.
The deceleration fuel cut control is started after the fuel cut prohibition time t1 has elapsed from the time when the idle control valve 66 was closed.

The control means 54 of the slip control device 52
Executes the ignition timing retard control so as to retard the ignition timing before the deceleration fuel cut control is started during the lapse of the fuel cut prohibition time t1. In this case, the control means 5
Reference numeral 4 designates an ignition timing delay time t2 provided between the time when the idle control valve 66 is closed and the time when the ignition timing retard control is started, and the ignition timing from the time when the idle control valve 66 is closed to the ignition timing. After the delay time t2 has elapsed, the ignition timing retard control is started.

In the second embodiment, the control means 54 of the slip control device 52 performs the ignition timing retard control when the shift control of the auxiliary transmission mechanism 16 of the automatic transmission 4 accompanies the slip control. Shift control is started. In this case, the control means 54 sets and provides the idle control valve opening delay time t3 between the time when the deceleration operation of the internal combustion engine 2 is started and the time when the idle control valve 66 is opened. When the shift control of the auxiliary transmission mechanism 16 of the automatic transmission 4 is accompanied by the idle control valve opening delay time t3 from the start of the deceleration operation of the internal combustion engine 2, the aisle control valve 66 is opened.

The slip control device 52 of the second embodiment
As shown in FIG. 2, the slip control sent from the transmission control unit 58 to the engine control unit 56 between the time when the deceleration operation is started and the time when the fuel cut control is executed, as shown in FIG. First signal SC1 and slip control second signal S
From the first state (STATE = 1) to the fifth state (RSTATE =
By processing the slip control according to 5), the shock when the lock-up clutch 24 is engaged in the half-engaged state and the shock when the fuel cut control is started are reduced. Since each state is the same as in the first embodiment, detailed description will be omitted.

Next, the operation of the second embodiment will be described with reference to FIG.

The slip control device 52 of the automatic transmission 2
As shown in FIG. 1, when the control starts (step 10).
0), the slip control second signal SC by the control means 54
It is determined whether or not 2 is on (step 102).
If this determination (step 102) is NO, it is determined whether the first slip control signal SC1 is on (step 104).

If the judgment (step 104) is NO, the fuel cut control and the slip control are not performed (step 106) and the operation is ended (step 108) in the 0th state (STATE = 0).

When the deceleration fuel cut condition is satisfied when the throttle valve is fully closed and the engine speed is equal to or higher than the fuel cut speed, and the determination (step 102) is YES, the first slip control signal SC1 is turned on. It is determined whether or not there is (Step 110).

If this determination (step 110) is NO, it is determined whether STATE ≧ 2 (step 112). If this determination (step 112) is NO, the first process is performed with the first state (STATE = 1) (step 114), and the process ends (step 108).

The first process (step 114) is a process when the shift control is performed during the execution of the slip control. This first processing is performed so as to perform shift control in the vicinity of the fourth state (STATE = 4) to the fifth state (STATE = 5).
From the fully closed throttle valve to the practical second state (STATE
= 2) This is a process for arbitrarily adjusting the time until the subsequent process is started. Also, the first processing (step 11)
In 4), preparation for slip control is started.

If the first processing (step 114) is completed and the judgment (step 110) is YES, the STAT
It is determined whether or not E ≧ 3 (step 116). If this determination (step 116) is NO, the second
The second process is performed with the state (STATE = 2) (step 118), and the process ends (step 108).

The second processing (step 11) of the second embodiment
8) is a process after the lapse of the idle control valve opening delay time t3 from the time when the throttle valve is closed. The idle control valve 66 is opened to increase the intake air amount by the idle air amount. The second process is a process for gently reducing the engine speed to secure the hydraulic pressure. The engine speed substantially matches the input shaft speed, and the duty value of the lock-up clutch 24 is half-engaged. When the target value for enabling the state is reached, the preparation for the slip control is completed, and the lock-up clutch 24 is engaged in the semi-engaged state, the operation ends.

If the second processing (step 118) is completed and the judgment (step 112) is YES, the third processing
The third processing is performed with the state (STATE = 3) (step 120), and the processing ends (step 108).

The third process (step 120) is a process for reducing the torque increased during the half-engagement of the lock-up clutch 24, in which the idle control valve 64 is closed to stop the supply of the idle air amount. Then, the increased intake air amount is returned to the original intake air amount.

If the third processing (step 120) is completed and the determination (step 116) is YES, the fourth processing
The fourth process is performed with the state (STATE = 4) (step 122), and the process ends (step 108).

The fourth process (step 122) is a process after the lapse of the ignition timing delay time t2 from the time when the idle control valve 66 is closed, and the ignition timing for delaying the ignition timing by the ignition timing adjusting means 70. Performs retard control.

When the shift control of the automatic transmission 4 is accompanied during the execution of the slip control, the shift control is started during the execution of the ignition timing retard control of the fourth process. In this case,
The control means 54 takes into account the time required from the time when the deceleration operation of the internal combustion engine 2 is started to the time when the shift control is started, so that the shift control is started during the execution of the ignition timing retard control. The idle control valve opening delay time t3 is set.

If the fourth processing (step 122) is completed and the judgment (step 104) is YES, the fifth processing
The fifth process is performed with the state (STATE = 5) (step 124), and the process ends (step 108).

The fifth process (step 124) is a fuel cut inhibition time t from the time when the idle control valve 66 is closed.
This is a process after 1 has elapsed, in which the fuel supply means 68 executes the fuel cut control and releases the slip control.

This fuel cut control is executed in the fifth process in which the engine speed is kept low (the torque is low) after the first to fourth processes of the slip control are completed. Can be reduced.

As described above, since the slip control device 52 of the second embodiment does not start the deceleration fuel cut control simultaneously with the completion of the preparation of the slip control as in the first embodiment, the lock-up clutch It is possible to reduce the occurrence of a shock due to a sudden decrease in the engine speed when the clutch 24 is engaged, and to reduce the occurrence of a shock due to a sudden decrease in the engine speed due to the stop of fuel.

Further, before starting the deceleration fuel cut control, the slip control device 52 further lowers the engine speed reduced by the closing operation of the idle control valve 66 by the ignition timing retard control, thereby reducing the deceleration fuel cut. The occurrence of a shock when the control is started can be further reduced. In this case, the slip control device 52 reduces the shock when the deceleration fuel cut control is started because the ignition timing delay time t2 exists before the engine speed is reduced due to the ignition timing retard. It can be realized by stepwise control.

Further, when the slip control device 52 of the second embodiment involves the shift control of the auxiliary transmission mechanism 16 of the automatic transmission 4 during the execution of the slip control, the slip control device 52 performs the shift during the execution of the ignition timing retard control. By starting the control, the shift control can be executed in a state in which the related rotation speed is reduced by the ignition timing retard control, so that the occurrence of a shock due to the shift can be reduced.

The slip control device 52 starts operating the idle control valve 6 from the time when the internal combustion engine 2 starts decelerating operation.
When the idle control valve opening delay time t3 is set and provided before the opening of the internal combustion engine 6, when the shift control of the auxiliary transmission mechanism 16 of the automatic transmission 4 is performed during the execution of the slip control, the deceleration of the internal combustion engine 2 is reduced. By opening the aisle control valve 66 after a lapse of the idle control valve opening delay time t3 from the start of the operation, the shift control can be reliably executed during the ignition timing retard control, so that the shock caused by the shift can be reduced. Occurrence can be reduced more reliably.

In the above embodiment, the idle control valve 66 is continuously opened. However, as shown in FIG. 7, a time tc for closing the idle control valve 66 is provided in the middle of the time to open the idle control valve 66. Open intermittently by
As shown in FIG. 8, a time t for opening the idle control valve 66
The closing time tc is provided in the middle of o and the opening time to is gradually shortened (to1>to2>... ton), while the closing time tc is gradually increased (tc1 <tc2.
tcn) can be opened intermittently and gradually.

As a result, the intake air amount increased by the opening operation of the idle control valve 66 can be easily adjusted with respect to the engine speed, and the intake air amount increased by the opening operation of the idle control valve 66 can be reduced. It can be gradually reduced as the engine speed decreases.

[0093]

As described above, the slip control device for an automatic transmission according to the present invention does not start the deceleration fuel cut control simultaneously with the completion of the slip control preparation. It is possible to reduce the occurrence of a shock due to a sudden decrease in the engine speed, and reduce the occurrence of a shock due to a sudden decrease in the engine speed due to the stop of the fuel.

Before starting the deceleration fuel cut control, the slip control device further reduces the engine speed reduced by the closing operation of the idle control valve by the ignition timing retard control to reduce the deceleration fuel cut control. , The occurrence of a shock at the time of starting can be further reduced. In this case, the slip control device gradually reduces the shock when the deceleration fuel cut control is started because there is an ignition timing delay time before the engine speed is reduced by the retardation of the ignition timing. Can be realized by simple control.

Further, since the slip control device can execute the shift control in a state where the engine speed is reduced by the ignition timing retard control, the occurrence of a shock due to the shift can be reduced. Further, since the slip control device can surely execute the shift control during the ignition timing retard control, it is possible to more reliably reduce the occurrence of a shock due to the shift.

[Brief description of the drawings]

FIG. 1 is a flowchart of control of a slip control device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing processing in each state of slip control.

FIG. 3 is a timing chart of control of the first embodiment.

FIG. 4 is a schematic configuration diagram of a slip control device of the automatic transmission.

FIG. 5 is a sectional view of the automatic transmission.

FIG. 6 is a control timing chart of the second embodiment.

FIG. 7 is a timing chart showing a first modification of the opening control of the idle control valve.

FIG. 8 is a timing chart showing a second modification of the opening control of the idle control valve.

FIG. 9 is a flowchart of control of a slip control device showing a conventional example.

FIG. 10 is a timing chart of control in a conventional example.

FIG. 11 is a diagram showing the contents of first and second slip control signals and a control signal according to a conventional example.

[Explanation of symbols]

 2 Internal combustion engine 4 Automatic transmission 14 Torque converter 16 Auxiliary transmission mechanism 24 Lock-up clutch 52 Slip control device 54 Control means 56 Engine control unit 58 Transmission control unit 60 Throttle opening sensor 62 Water temperature sensor 64 Engine speed sensor 66 Idle control Valve 68 Fuel supply means 70 Ignition timing adjustment means 72 Input shaft speed sensor 76 Solenoid valve for lock-up clutch

Claims (5)

[Claims] An idle control valve for controlling an amount of idle air in an idle intake passage that bypasses a throttle valve of an internal combustion engine mounted on a vehicle and communicates with an intake passage is provided. A lock-up clutch for adjusting the slip of the torque converter is provided, and during deceleration operation of the internal combustion engine, the idle control valve is opened so as to increase the intake air amount of the internal combustion engine and the slip of the torque converter is limited. Preparation for slip control for engaging the lock-up clutch in the half-engagement state is started, and after the preparation for the slip control is completed and the lock-up clutch is engaged in the half-engagement state, the idle control valve is closed. Of the automatic transmission, which starts the deceleration fuel cut control so as to stop the fuel supply to the internal combustion engine while operating. In the control device, a fuel cut prohibition time is set and provided between the time when the idle control valve is closed and the time when the deceleration fuel cut control is started, and the time from when the idle control valve is closed is set. A slip control device for an automatic transmission, further comprising control means for starting the deceleration fuel cut control after a fuel cut prohibition time has elapsed. 2. The control unit executes an ignition timing retard control so as to retard an ignition timing before the deceleration fuel cut control is started during the lapse of the fuel cut prohibition time. The slip control device for an automatic transmission according to claim 1, wherein: 3. The control means sets and provides an ignition timing delay time between the time when the idle control valve is closed and the time when the ignition timing retard control is started, and sets the idle control valve. 3. The slip control device for an automatic transmission according to claim 2, wherein the control unit starts the ignition timing retard control after the ignition timing delay time has elapsed from the time of closing. 4. A control means for starting a shift control during execution of the ignition timing retard control, when a shift control of an auxiliary transmission mechanism of the automatic transmission is accompanied during execution of the slip control. The slip control device for an automatic transmission according to claim 2, wherein: 5. The control device according to claim 1, wherein the control means sets an idle control valve opening delay time between a time when the deceleration operation of the internal combustion engine is started and a time when the idle control valve is opened, and executes the slip control. Control means for opening the aisle control valve after elapse of the idle control valve opening delay time from the start of the deceleration operation of the internal combustion engine when the shift control of the auxiliary transmission mechanism of the automatic transmission is accompanied during The slip control device for an automatic transmission according to claim 4, wherein: