JP2000255284A - Vehicle control system with fuel cutting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle control system having a fuel cutting device which can reduce the shock of a vehicle which occurs when disconnection of a lockup clutch and re-injection of fuel are performed with the use of the fuel cutting device, and which can prevent the stop of the engine which may be caused by the undershoot of the engine. SOLUTION: When a lockup clutch 18 is disconnected and an engine 12 is separated from a CVT 16 (drive wheel side) and shifts into idle, an ECU 28 increases the output of the engine 12 from the engine output required to maintain idling rotation, so as to reduce a difference in torque between before and after disconnection of the lockup clutch 18 to reduce shock generated in the vehicle and to prevent the stop of the engine resulting from the undershoot of the engine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control apparatus for a vehicle having a fuel cut-off device for an engine, and more particularly to a vehicle shock and an undershoot of an engine speed which occur when returning from a fuel cut. To a control device that can

[0002]

2. Description of the Related Art Conventionally, in some vehicles equipped with an automatic transmission (including a continuously variable transmission), when the vehicle is running at a reduced speed, for example, the engine speed is lower than a predetermined fuel cut lower limit speed. Until now, there is a fuel cut device that cuts off fuel to be supplied to the engine. In such a vehicle, fuel is not consumed at the time of decelerating running that does not require the output of the engine, so that the running fuel efficiency of the vehicle is improved. Since the effect of improving the running fuel efficiency increases as the fuel cut range increases, it is desirable to set the fuel cut lower limit rotational speed as low as possible.

[0003] For example, Japanese Patent Publication No. 7-12807 discloses mechanical connection and disconnection of power between an engine and driving wheels while fuel supplied to the engine is cut off by a fuel cut device. It is conceivable to rotate the engine by transmitting the running force of the vehicle to the engine via the lock-up clutch with the lock-up clutch performing the operation being engaged (connected). With this configuration, while the fuel to be supplied to the engine is cut off by the fuel cut device, the lock-up clutch is in the engaged state (including the state in which the fuel can be slipped by half-engagement) and the vehicle is driven. Since the rotation force is transmitted to the engine, the rotation speed of the engine during deceleration is gradually reduced according to the vehicle speed. As a result, the fuel cut range is increased. As a result, the lock-up clutch is disconnected (released) from the beginning when the vehicle decelerates
The driving fuel efficiency of the vehicle is improved compared to the case where

When the engine speed falls below the fuel cut lower limit rotation speed, the lock-up clutch is disengaged (disengaged) to make the engine free from driving wheels (connected with fluid), The fuel injection is restarted, and the engine is driven autonomously to maintain the idling rotation. When the accelerator is depressed, the output of the engine is increased and the lock-up clutch is connected again to transmit the output of the engine to the drive wheels.

[0005]

However, when the fuel cut by the above-described fuel cut device is performed, the rotation speed of the driven engine or the engine torque decreases as the vehicle speed decreases. . In order to maintain the idling of the engine while the torque of the driven engine is reduced, it is necessary to put the engine in a free state (a fluid connection state), terminate the fuel cut, and restart the fuel injection. However, since there is a torque step between the engine torque generated with the return of the fuel injection and the torque immediately before the engine becomes free (during a driven state), as shown in the timing chart of FIG. When the lockup clutch is disengaged (lockup state ON → OFF) and fuel is re-injected (fuel cut state ON → OFF), a shock occurs in the vehicle due to a sudden change in torque (vehicle longitudinal acceleration),
There is a problem of giving a discomfort to a vehicle occupant.

In general, since the actual increase in the torque of the engine is delayed in response to the fuel injection instruction to the engine, when the lock-up clutch is disengaged and the engine becomes free, the engine speed undershoots below a predetermined speed. Then, there is also a problem that the engine may be stopped (stalled).

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and can reduce a shock of a vehicle that occurs when a lock-up clutch is disconnected and fuel is re-injected due to use of a fuel cut device. It is an object of the present invention to provide a vehicle control device provided with a fuel cut device. Also provided is a vehicle control device provided with a fuel cut device capable of preventing engine stop due to engine undershoot even when the lock-up clutch is disconnected and fuel is re-injected due to use of the fuel cut device. The purpose is to do.

[0008]

In order to achieve the above object, a first aspect of the present invention is to provide a lock-up mechanism for mechanically connecting and disconnecting power between an engine and the engine and driving wheels. A control device for a vehicle, comprising: a torque converter with a clutch; and a fuel cut device that cuts off fuel supplied to the engine until a predetermined vehicle running state while connecting a lock-up clutch when the vehicle is running at a reduced speed. When the vehicle travel state is reached and the lock-up clutch is disengaged and the fuel cut device is returned from fuel cutoff, the engine output is increased by a predetermined amount from the idling maintenance output from the time of the fuel injection return, and then the idling maintenance is performed. It is characterized by returning to output.

Here, the predetermined vehicle traveling state is, for example,
This is a constant vehicle state that can be determined based on vehicle speed, engine speed, and the like. The predetermined amount to be increased from the idling maintenance output is an amount that can be specified by measuring the time with a timer or the like and setting the range by changing the vehicle speed, and the specific increase in the engine output is performed by adjusting the fuel injection amount, the intake air amount, and the like. Do.

According to this structure, when the lock-up clutch is disengaged, the torque can be increased by increasing the engine output, so that the torque step when the lock-up clutch is disengaged can be reduced, and the shock to the vehicle can be reduced. The undershoot of the engine speed can be prevented.

In order to achieve the above object, a second invention is directed to an engine, a torque converter with a lock-up clutch for connecting and disconnecting power between the engine and driving wheels, and a vehicle deceleration. A fuel cut device that shuts off fuel supplied to the engine until a predetermined vehicle traveling state while connecting the lock-up clutch during traveling. A predetermined time before cutting is performed, the fuel cut device is returned from the fuel cut-off state so that the engine output is gradually increased so that the engine output becomes larger than the idling maintenance output, and is returned to the idling maintenance output after the lapse of the predetermined time. It is characterized by the following.

According to this configuration, the control for increasing the engine output is gradually started prior to the disconnection of the lock-up clutch. Therefore, when the lock-up clutch is disconnected, the torque step is completely eliminated, and the change in the engine speed is reduced. As a result, it is possible to reliably and effectively reduce the shock of the vehicle (shock when returning from the fuel cut) and suppress the engine stall.

According to a third aspect of the present invention, in the first or second aspect, the amount of increase and decrease of the engine output when the fuel cut device returns from the fuel cut-off state. Is determined based on the deceleration of the vehicle.

According to this configuration, the increase or decrease of the engine output is appropriately selected according to the degree of deceleration of the vehicle, so that it is possible to more reliably and effectively reduce the shock of the vehicle and suppress the engine stall.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention (hereinafter referred to as embodiments) will be described below with reference to the drawings.

FIG. 1 is a schematic configuration diagram of a vehicle control device 14 including a fuel cut device 10 and an engine 12 according to an embodiment of the present invention. The vehicle in this embodiment is one in which, for example, a continuously variable transmission 16 is connected to the output side of the engine 12.

The continuously variable transmission (hereinafter referred to as CVT; Continuo)
The usly variable transmission 16 is a transmission that can continuously change the gear ratio, and changes the groove width between the drive-side pulley and the driven-side pulley by hydraulic pressure. Belt type CVT that changes the winding radius by changing the winding radius
Alternatively, it is possible to use a toroidal CVT in which a power roller is sandwiched between a pair of disks having a toroidal surface, and the power roller is tilted to change the radius of a point of contact with the disk to perform gear shifting. In the belt-type CVT, the gear ratio changes by changing the groove width of each pulley while keeping the tension applied to the belt constant, and the changing speed of the groove width becomes the gear changing speed. Accordingly, the speed change speed can be arbitrarily controlled by hydraulic control for supplying and discharging the actuator that drives the movable sheave in each pulley.

In FIG. 1, the engine 12 and the CVT
A torque converter 20 having a lock-up clutch 18 and a forward / reverse switching mechanism 22 are disposed between the torque converter 20 and the power converter 16. The torque converter 20 is basically for intermittently operating the engine 12 even when the vehicle is stopped. The forward / reverse switching mechanism 22 is provided because the rotation direction of the engine 12 is limited to one direction and the CVT 16 does not have a reversing operation mechanism, and is a mechanism mainly composed of a planetary gear mechanism. And a mechanism including a reverse gear and a synchronous connection mechanism.

Further, a differential 26 is connected to the output shaft 24 of the CVT 16 via a gear. Therefore, the lock-up clutch 1 of the torque converter 20
8 with the engine 12 and the CVT 1
6 and the output of the engine 12 is CVT
The engine 12 can be driven by the driving wheels by rotating the CVT 16 by the driving wheels while transmitting the power to the driving wheels via the driving wheels 16. In addition, the mechanical connection between the engine 12 and the CVT 16 is disconnected by disconnecting the lock-up clutch 18 (disengaged) (the fluid connection is made by the torque converter 20), and the engine 12 is driven autonomously. It is also possible to put it in a state.

Further, the control device 14 controls the engine 1
Control unit (EC) for controlling CVT2 and CVT16
U) 28, 30. These ECUs 28, 3
Numeral 0 is mainly composed of a microcomputer. The ECU 28 for the engine receives data such as the accelerator opening Acc and the engine speed Ne, and inputs the data to the engine 1.
The fuel cut device 10 controls the fuel injection amount, injection timing, intake air amount, and the like for the fuel cut device 10.
Exchanges data with the Also, ECU
The ECU 30 controls the shift speed and rotation speed of the CVT 16 by the ECU.
28 based on the exchange of data. That is, the ECUs 28 and 30 are configured to control the output of the engine 12 in accordance with the input data and the program stored in advance, and to control the speed ratio and speed of the CVT 16.

The fuel cut device 10 includes a CVT 16 which is rotated by driving a drive wheel and an engine 12 through a lock-up clutch 18 during deceleration running of the vehicle.
And the engine 1 up to a predetermined vehicle running state.
2 to shut off the fuel to be supplied. Here, the vehicle running state is, for example, a predetermined fuel cut lower limit (for example, 800 rpm when determined by the engine speed, 15 km / h when determined by the vehicle speed).
It is. Thus, the fuel consumption of the vehicle is improved by preventing the fuel from being consumed during the deceleration running that does not require the output of the engine 12. Further, when the state of the engine 12 becomes equal to or lower than the fuel cut lower limit value, the fuel cut device 10 disconnects (releases) the lock-up clutch 18 to make the engine 12 free with respect to the drive wheels. With Engine 1
The fuel injection to the fuel cell 2 is restarted and the engine 12 is driven autonomously to maintain the idling rotation. When the accelerator is depressed, the ECU 28 increases the output of the engine 12 and connects the lock-up clutch 18 again to transmit the output of the engine 12 to the drive wheels.

Embodiment 1 The features of the first embodiment are as follows.
When the state of the engine 12 becomes equal to or lower than the fuel cut lower limit, the lock-up clutch 18 is disengaged (released), and the engine 12 is set in a free state with respect to the driving wheels, and the fuel is injected into the engine 12. When the engine 12 is restarted and the engine 12 is driven autonomously, that is, the output of the engine 12 is increased by a predetermined amount from the idling maintenance output after the lock-up clutch 18 is disconnected, thereby suppressing a torque step before and after the lock-up clutch 18 is disconnected. Is about to do. Specifically, normally, an engine output larger than the engine output necessary to maintain idling rotation is generated to complement the torque, thereby preventing a shock due to a torque step and an undershoot of the engine speed.

FIG. 2 shows a control flag, a fuel increase value, a fuel injection amount, an engine speed, C
A timing chart such as the VT rotation speed is shown. 3 and 4 show control flowcharts of the first embodiment.

As shown in FIG.
CU28 is always idle switch (accelerator is OFF
Is turned on or not, and the lock-up clutch 18 is turned on, that is, the engine 12
It is detected whether or not the CVT 16 and the CVT 16 are in an engaged state (including a state in which slippage is possible due to half-engagement) (S100).

In this embodiment, the engine 12 and the C
Although an example in which an idle switch is used as a means for detecting the engagement state with the VT 16 is shown, similar state detection may be performed by using a device that detects a throttle opening and an accelerator opening. it can.

If the idle switch is ON and the lock-up clutch is ON, the ECU 28 controls the fuel cut device 10 to perform fuel cut, that is, prohibits fuel injection to the engine 12 to thereby suppress fuel consumption (S101). On the other hand, when one or both of the idle switch and the lock-up clutch are OFF, the ECU 28 issues a fuel injection return instruction to the fuel cut device 10 (S10).
2).

At this time, the amount of fuel to be injected into the engine 12 is determined according to an increase value calculation routine shown in the flowchart of FIG. First, the ECU 28 determines whether or not the lock-up clutch 18 has changed from the ON state to the OFF state (S103). The change from the ON state to the OFF state of the lock-up clutch 18 may be directly recognized by the sensor or the like, but the change in the lock-up clutch 18 is performed when the vehicle speed is P1 (P1 ( 15km / h)
Since the determination is performed at the time of the following, the determination can be made based on the change in the vehicle speed as shown in FIG. If the lock-up clutch 18 changes from the ON state to the OFF state, the ECU 28 determines a predetermined fuel increase initial value A based on the deceleration (calculated from the vehicle speed change) as shown in FIG. Is calculated based on the calculation map (S
104). The increase initial value A is set to increase as the deceleration increases, that is, as the vehicle decelerates rapidly. Subsequently, as shown in FIG. 5C, the ECU 28 calculates an upper limit value C at the time of fuel increase based on deceleration (calculated from a change in vehicle speed) (S105). ≦ C) is set (S106). Here, the upper and lower limit values are set so that the ECU 28 demands an engine output larger than the engine output originally required to maintain the idling rotation together with the disconnection of the lock-up clutch 18, but the request is not excessive. The upper limit is set to increase as the vehicle decelerates rapidly.

Further, as shown in FIG. 5D, the ECU 28 determines a reflection coefficient D of the fuel increase value based on the rotation speed of the engine 12 (S107). The reflection coefficient D is for preventing the engine 12 from being excessively supplied with an excessive supply of fuel. The reflection coefficient D is shown in FIG.
As shown in (d), the engine speed is set to decrease as the engine speed becomes higher than a predetermined engine speed, and when the engine 12 rotates at a certain high speed, the fuel increase value is reduced.

The ECU 28 integrates the reflection coefficient D and the increase value with the upper and lower limits limited (S108), and increases the increase reflection value, that is, the amount of fuel actually supplied to the engine 12 when the lock-up clutch 18 is disengaged. Determine the value (S1
09), the process proceeds to the next processing cycle, that is, (S103).

On the other hand, if the ECU 28 determines in step S103 that the lock-up clutch 18 has already been turned off, it is necessary to increase the fuel supply amount to a predetermined amount, for example, to maintain the idling rotation of the engine 12. In order to gradually return to the fuel injection amount necessary for obtaining the engine output, a fuel attenuation amount B determined based on the deceleration vehicle speed is calculated as shown in FIG. 5B (S11).
0). The amount of attenuation B is also set to increase as the vehicle speed rapidly decreases. Then, a value obtained by subtracting the attenuation amount B calculated in (S110) from the increase value calculated in the previous processing cycle (the process proceeds to this step after the increase value is once calculated) is calculated as a new increase value. As (S1
11) The processing of (S105) to (S109) is performed to determine the fuel increase value at the present time.

As a result, as shown in the timing chart of FIG. 2, the lock-up clutch 18 is turned off,
At the same time that the fuel cut is OFF, that is, the fuel injection supply to the engine 12 is restored, the engine 1
The fuel is injected by a predetermined amount larger than the fuel injection amount for maintaining the idling rotation of No. 2. As a result, the engine output of the engine 12 is complemented, the torque step when the lock-up clutch 18 is disconnected is reduced, and the shock (the longitudinal acceleration of the vehicle) when the engine 12 shifts to idling is reduced. Further, by complementing the engine output when the lock-up clutch 18 is disengaged, undershoot of the engine speed is reduced, and engine stall can be reliably prevented.

The fuel increased when the lock-up clutch 18 is disengaged is supplied to the lock-up clutch 18
As the time elapses from the disconnection, the attenuation amount B is sequentially subtracted, gradually decreased, and finally the increased value becomes 0,
The fuel injection amount eventually converges to the idling maintenance injection amount.

The ECU 28 calculates the fuel increase value as shown in FIG.
As shown in (a) to (c), the increase value is changed according to the deceleration. FIG. 6A shows a timing chart for increasing the fuel when the deceleration is small, and FIG. 6B shows a timing chart for increasing the fuel when the deceleration is large. This is because when the deceleration is abrupt, the torque step becomes large. Therefore, when the deceleration is large, the control is started at a vehicle speed P2 which is earlier than when the deceleration is small. In order to supplement the above, the increase value of the injected fuel and the increasing / decreasing speed of the injected fuel are increased to reduce the shock of the vehicle and suppress the engine stall suitable for the vehicle running state.

Embodiment 2 In the first embodiment described above, after recognizing the change of the lock-up clutch 18 from ON to OFF, the fuel is returned to the increased-injection mode. However, even if the fuel is injected into the engine 12, the engine output increases. There is a time lag until. Therefore, FIG.
As shown in FIG. 6B, it was difficult to completely eliminate the undershoot of the rotation speed of the engine 12.

The characteristic feature of the second embodiment is that the fuel return is started before the lock-up clutch 18 is disconnected,
The output increase control of the engine 12 is gradually started to completely eliminate the undershoot of the rotation speed of the engine 12 when the lock-up clutch 18 is disengaged, and smooth the change in the engine rotation speed to reduce the shock of the vehicle. And the engine stall is surely and effectively performed.

FIG. 7 shows a control flag, fuel increase value, fuel injection amount, engine speed,
A timing chart of the CVT rotation speed and the like is shown.
FIG. 8 shows a control flowchart of the second embodiment.

As shown in FIG. 7, the change from ON to OFF of the lock-up clutch 18 can be determined based on whether or not the vehicle speed has fallen below a predetermined value, as in the first embodiment. When the fuel is returned at the same time when the lock-up clutch 18 is disconnected, the undershoot of the engine speed cannot be eliminated. Therefore, in the second embodiment, as shown in FIG. The timing is quick.

That is, in the flowchart of FIG. 8, when the vehicle is in the deceleration state, the ECU 28 calculates the OFF timing of the pre-lockup flag (S20).
0). The lock-up pre-OFF flag is, for example, a flag that is turned off a predetermined time before the vehicle speed P1 at which a preset lock-up clutch is determined to be OFF, and can be calculated backward based on the deceleration calculated from the vehicle speed. Alternatively, the flag operation vehicle speed Q1 (for example, 17 km / h) may be simply set for the vehicle speed P1 (for example, 15 km / h), and the flag before lock-up OFF may be turned off. Next, the ECU 28 determines whether or not the lock-up pre-OFF flag has actually changed from the ON state to the OFF state (S201). This change can be determined, for example, based on whether or not the vehicle speed has fallen below Q1 (17 km / h).

If the lock-up OFF flag is ON
When the state changes from the OFF state to the OFF state, the ECU 28 sets a predetermined fuel increase initial value A based on the deceleration (calculated from the vehicle speed change) as shown in FIG. It is calculated (S202). Hereinafter, similarly to the first embodiment, the upper limit value C at the time of fuel increase is calculated based on the deceleration (calculated from the change in vehicle speed) (S203), and upper and lower limits (0 ≦ increase value ≦ C) are set for the increase value. Yes (S2
04). Further, as shown in FIG. 5D, the ECU 28 determines the reflection coefficient D of the fuel increase value based on the rotation speed of the engine 12 (S205), and integrates the reflection coefficient D and the increase value with the upper and lower limits restricted (S205). S206), an increase reflection value, that is, an increase amount of the fuel actually supplied to the engine 12 when the lock-up pre-OFF flag changes (S206).
207).

On the other hand, if the ECU 28 determines in step S201 that the lock-up pre-OFF flag has already been changed to OFF, the increased fuel supply amount is required to maintain a predetermined amount, for example, to keep the engine 12 idling. In order to gradually return to the fuel injection amount necessary to obtain a proper engine output, a fuel attenuation amount B determined based on the deceleration vehicle speed is calculated as shown in FIG. 5B (S20).
8). Then, the value obtained by subtracting the attenuation amount B calculated in (S208) from the previously calculated increase value is set as a new increase value (S209), and the processes of (S203) to (S207) are performed to determine the current increase value of the fuel. I do.

As a result, as shown in the timing chart of FIG. 7, the lock-up pre-OFF flag is turned off, and the fuel cut is turned off, that is, the engine 12
At the same time as the return of the fuel injection supply to the engine 12, the fuel starts to be injected by a predetermined amount larger than the fuel injection amount for maintaining the idling rotation of the engine 12. At this point, the lock-up clutch 18 is still in the engaged state, and in this state,
By the time the engine output of the engine 12 is complemented and the lockup clutch 18 is disengaged, the torque step can be eliminated. By eliminating the torque step, no torque fluctuation occurs even when the lock-up clutch 18 is disconnected, and no undershoot of the engine speed occurs. That is, the shock (the longitudinal acceleration of the vehicle) when the engine 12 shifts to idling is further reduced than in the first embodiment. Further, by complementing the engine output before the lock-up clutch 18 is disengaged, an undershoot of the engine speed is eliminated, and engine stall can be reliably prevented.

The amount of fuel that was increased when the lock-up clutch 18 was disengaged is gradually reduced as the time elapses after the disengagement of the lock-up clutch 18, gradually decreased, and finally increased. Becomes zero, and the fuel injection amount finally converges to the idling maintaining injection amount.

It should be noted that also in the second embodiment, the fuel increase value depends on the deceleration as shown in FIGS.
The increase value is changed. FIG. 9A shows a timing chart regarding the fuel increase when the deceleration is small, and FIG. 9B shows a timing chart regarding the fuel increase when the deceleration is large. In other words, when abrupt deceleration is performed, the torque step becomes large, so that the control is started at a vehicle speed Q2 faster than when the deceleration is small, and the amount of injected fuel is increased to sufficiently compensate for the torque step at that time. The value is increased, and the shock of the vehicle suitable for the running state of the vehicle is reduced and the engine stall is suppressed.

As described above, since the return of the fuel injection is gradually started prior to the disconnection of the lock-up clutch 18, the shock at the time of returning from the fuel cut is reduced, and the shock and the engine accompanying the disconnection of the lock-up clutch 18 are reduced. The rotation undershoot can be reliably prevented.

In each of the above-described embodiments, a configuration in which the fuel injection amount is made larger than the injection amount necessary for idling rotation based on the disconnection change of the lock-up clutch 18 will be described. However, if the engine output before and after the disengagement of the lock-up clutch 18 is made larger than the engine output required for idling rotation, the same effect as that of the present embodiment can be obtained, and the fuel consumption can be increased. The amount and the rate of increase and decrease of the fuel and the calculation method thereof can be appropriately selected.

[0046]

According to the present invention, when the lock-up clutch is disengaged and the fuel is re-injected with the use of the fuel cut device, the output of the engine is reduced from the engine output required to maintain idling. By increasing the amount by a fixed amount, the torque step when the lock-up clutch is disconnected is reduced. As a result, it is possible to reduce the shock due to the torque step and to prevent the engine from stopping due to the undershoot of the engine, and it is possible to eliminate the discomfort of the vehicle occupant.

[Brief description of the drawings]

FIG. 1 is a configuration block diagram illustrating a schematic configuration of a control device for a vehicle including a fuel cut device according to an embodiment of the present invention.

FIG. 2 is a timing chart of a fuel return control of the fuel cut device according to the first embodiment of the present invention.

FIG. 3 is a flowchart illustrating a fuel cut execution determination according to the first embodiment of the present invention.

FIG. 4 is a flowchart illustrating a fuel increase calculation routine according to the first embodiment of the present invention.

FIG. 5 is a calculation map of each calculation value when calculating a fuel increase in the embodiment of the present invention.

FIG. 6 is a timing chart of control for comparing when the deceleration speed is low and when the deceleration speed is high in the first embodiment of the present invention.

FIG. 7 is a timing chart of fuel return control of a fuel cut device according to Embodiment 2 of the present invention.

FIG. 8 is a flowchart illustrating a fuel increase calculation routine according to a second embodiment of the present invention.

FIG. 9 is a timing chart of control for comparing a case where the deceleration speed is low and a case where the speed is high in the second embodiment of the present invention.

FIG. 10 is a timing chart of fuel return control of a conventional fuel cut device.

[Explanation of symbols]

10 fuel cut device, 12 engine, 14
Control device, 16 continuously variable transmission (CVT), 18 lock-up clutch, 20 torque converter, 22 forward / reverse switching mechanism, 24 output shaft, 26 differential, 28, 30 ECU.

Continued on the front page F-term (reference) 3D041 AA36 AA59 AB01 AC01 AC09 AC19 AD02 AD04 AD10 AD18 AD51 AE03 AE07 AE08 AE16 AF09 3G092 BB01 BB10 CB05 DE01S EA01 EA02 EA08 EA17 EB08 FA04 FA40 GA04 GB08 HA09ZH06 EB08 HA09ZH03A01 BA02 BA05 CA00 CA04 CB07 DA01 DA06 DB11 DB23 EA05 EB03 FA11 FB01 FB03 3G301 HA00 JA04 JA31 KA27 KB00 LB01 LB11 MA11 MA25 NA04 NA08 NB02 NB06 NB11 NE01 NE03 NE08 NE17 NE23 PA14Z PE01Z PF01Z PF02PF08ZPF03

Claims (3)

[Claims] An engine, a torque converter with a lock-up clutch for mechanically connecting and disconnecting power between the engine and driving wheels, and a predetermined vehicle connected with the lock-up clutch during deceleration traveling of the vehicle A fuel cut device that cuts off fuel supplied to the engine until the vehicle travels, wherein the vehicle reaches a predetermined vehicle travel state, disconnects the lock-up clutch, and shuts off the fuel by the fuel cut device. A control device for a vehicle equipped with a fuel-cut device, wherein the engine output is increased by a predetermined amount from the idling maintenance output from the time of the fuel injection restoration, and then returned to the idling maintenance output. 2. An engine, a torque converter with a lock-up clutch for connecting and disconnecting power between the engine and driving wheels, and a predetermined vehicle running state while the lock-up clutch is connected when the vehicle is running at a reduced speed. A fuel cut-off device for shutting off fuel supplied to the engine up to a predetermined time before a predetermined vehicle running state is reached and the lock-up clutch is disengaged. Control of a vehicle equipped with a fuel cut device, wherein the return from fuel cut-off is gradually increased so that the engine output becomes larger than the idling maintenance output, and is returned to the idling maintenance output after a predetermined time has elapsed. apparatus. 3. The system according to claim 1, wherein the amount of increase and decrease of the engine output when the fuel cut device returns from the fuel cutoff is determined based on the deceleration of the vehicle. A vehicle control device provided with a fuel cut device.