JPH0712807B2 - Control method for vehicle equipped with fuel cut device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for controlling a vehicle provided with an engine fuel cut device, and more particularly to a technique for improving fuel efficiency of the vehicle.

2. Description of the Related Art During deceleration of a vehicle, a vehicle is provided with a fuel cut device that shuts off fuel to be supplied to the engine until the engine speed falls below a predetermined fuel cut lower limit rotation speed. In such a vehicle, fuel is not consumed during decelerating traveling that does not require the output of the engine, so the traveling fuel efficiency of the vehicle is improved. Since the effect of improving the running fuel consumption becomes larger as the fuel cut range is expanded, it is desirable to set the fuel cut lower limit rotation speed as low as possible.

Therefore, it is conceivable that the engine is rotated by transmitting the running force of the vehicle to the engine through the clutch while the clutch is engaged while the fuel cut by the fuel cut device is interrupted. With this configuration, while the fuel to be supplied to the engine is cut off by the fuel cut device, the clutch is engaged and the rotational force generated by the running of the vehicle is transmitted to the engine. Since the speed is gradually reduced according to the vehicle speed, and the fuel cut range is expanded thereby, the running fuel consumption of the vehicle is improved compared to the case where the clutch is released during deceleration of the vehicle.

SUMMARY OF THE INVENTION However, in such a control method, while the fuel to be supplied to the engine is shut off by the fuel cut device, the clutch is engaged and transmitted to the rotary engine due to traveling of the vehicle. Therefore, the engine braking effect occurs in the vehicle, the running resistance at the time of the fuel cut increases, and the coasting period cannot be sufficiently obtained. Further, when the fuel supply to the engine is restarted, the output torque of the engine is directly transmitted to the input shaft of the transmission, which may give a shock to the driver.

Means for Solving the Problems The present invention has been made in the background of the above circumstances,
The gist of the present invention is to provide a fuel cut device that shuts off fuel to be supplied to the engine until the engine speed falls below a predetermined fuel cut lower limit rotation speed when the vehicle is decelerated, and the power of the engine is controlled. A method of controlling a vehicle in which transmission is performed to a transmission and a drive wheel via a controllable clutch, wherein the clutch is in a half-engaged state while fuel to be supplied to an engine is shut off by the fuel cut device. In addition, the clutch is slipped within a range in which a transmission torque larger than a value required to restart the engine is obtained.

With this, the clutch is half-engaged while the fuel to be supplied to the engine is shut off by the fuel cut device, and the clutch is necessary for restarting the engine. Since the vehicle is slipped in a range in which a transmission torque larger than the above value can be obtained, the running resistance of the vehicle at the time of fuel cut is reduced as much as possible, and the coasting period is extended. Further, when the fuel supply is restarted, the engine is surely restarted and the output torque of the engine is not directly transmitted to the input shaft of the transmission, so that the shock to the driver is reduced.

Here, the engagement controllable clutch is a clutch that can be controlled to be in a non-engaged state in which the transmission torque is at least zero and a state in which the transmission torque exists, and the transmission torque changes according to a foot operation. It does not include a manual clutch, a fluid clutch whose transmission torque changes according to the relative rotation speed, and a centrifugal clutch.

Preferably, the clutch is controlled so that a torque that increases as the input rotation speed of the transmission decreases becomes transmitted. By doing so, the engine is rotated by the running force of the vehicle at a rotation speed and torque necessary and sufficient for restarting the engine, so that the running resistance of the vehicle is further reduced and the fuel cut range is further improved. Expanded.

Further, the fuel cut lower limit rotation speed is preferably changed in association with the traveling speed of the vehicle, the accelerator operation amount, the operation position of the shift lever, and the operating state of the air conditioner. With this configuration, the fuel cut lower limit rotation speed can be made as small as possible in accordance with the traveling speed of the vehicle, the accelerator operation amount, the operation position of the shift lever, and the operating state of the air conditioner. In addition, since the clutch is disengaged when the shift lever is operated in the neutral range, it is desirable that the fuel cut lower limit rotation speed be determined to be higher than the idle rotation speed of the engine. Further, when the shift lever is operated to the forward range or the reverse range, it is desirable that the rotation speed is determined to be lower than that when the shift lever is operated to the neutral range. With this configuration, the fuel cut range is expanded in the range in which the clutch is engaged.

The engagement controllable clutch preferably has a transmission torque before start of fuel cutoff when a predetermined delay time elapses when the fuel cut device stops cutoff of fuel to be supplied to the engine. It can be returned to the state of transmitting power. With this configuration, the engine is driven in accordance with the running of the vehicle for a predetermined delay time after the fuel cut is released, and the restart of the engine is further ensured.

Embodiment Hereinafter, a detailed description will be given based on the drawings showing an application example of the present invention.

FIG. 2 shows a vehicle engine 10, a magnetic powder type electromagnetic clutch 12,
1 shows a control device for controlling the belt type continuously variable transmission 14. The engine 10 is a diesel engine in this embodiment, and its output is changed according to the amount of fuel supplied from the fuel injection device 16. Magnetic powder type electromagnetic clutch 12
Is a well-known clutch capable of engagement control and transmission torque control, in which magnetic particles filled in a narrow gap between an input side rotating body and an output side rotating body are magnetically coupled. Thereby transmitting power and changing the transmission torque in response to a change in the exciting current supplied from the outside. The belt type continuously variable transmission 14 includes an input side variable pulley 18 and an output side variable pulley 20 each having a variable effective diameter, a transmission belt 22 wound around the variable pulleys 18 and 20, an input side variable pulley 18 and an output side variable pulley 18. A hydraulic actuator (not shown) that changes the V groove width of the side variable pulley 20, that is, the effective diameter, is provided, and the hydraulic oil supply amount or hydraulic oil discharge amount to the input hydraulic actuator is adjusted by the flow control servo valve 28. As a result, the speed ratio of the belt type continuously variable transmission 14 (the rotation speed of the output side rotary shaft / the rotation speed of the input side rotary shaft) is controlled, and the working hydraulic pressure in the output side hydraulic actuator is controlled by the pressure control servo valve 30. Is changed so that the narrow pressure on the transmission belt 22 is changed so that the transmission capacity is adjusted to be necessary and sufficient. The output shaft of the belt type continuously variable transmission 14 is connected to the drive wheels of the vehicle through a differential device (not shown), and the power of the engine 10 is eventually a magnetic powder type electromagnetic clutch.
12, a belt type continuously variable transmission 14, and a differential device for transmission to drive wheels.

The first control device 32 is for exclusively controlling the transmission torque of the magnetic powder type electromagnetic clutch 12 and the speed ratio of the belt type continuously variable transmission 14, and includes a CPU 34, a ROM 36, a RAM 38, an input interface 40, an output interface. Equipped with 42. The input interface 40 includes a signal SF indicating the shift lever position from the shift lever position sensor 23 and an accelerator pedal sensor 25.
To the signal A _cc indicating the amount of operation of the accelerator pedal, the engine rotation sensor 27 indicating the engine rotation speed SE, and the rotation sensors 24 and 26 indicating the rotation signal SR1 corresponding to the rotation of the input side variable pulley 18 and the output side variable pulley 20. And SR2 are supplied, and the engine 10 is supplied from a sensor (not shown).
And a signal indicating the operating state of the belt type continuously variable transmission 14, for example, a signal indicating an engine cooling water temperature, a signal indicating a hydraulic oil temperature, a signal from a power / economy running selection switch, a signal indicating a running road gradient, and a brake operation. Is input. The CPU 34 processes a signal input from the input interface 40 according to a program previously stored in the ROM 36, and outputs the speed ratio signal V _a and the line pressure signal V _L via the output interface 42 to the flow control servo valve 28 and the pressure control servo valve 30. Is output to the second control device 44 while outputting a signal indicating the optimum output torque of the engine 10, in other words, a target output torque T _e ^* and a fuel cut signal F for obtaining the optimum output, to the second control device 44. A signal T _c representing a different transmission torque is supplied to the drive circuit 29, and an exciting current for obtaining the transmission torque is supplied from the drive circuit 29 to the magnetic powder type electromagnetic clutch 12.

The second control device 44 is exclusively for controlling the output torque of the engine 10, and includes a CPU 46, a ROM 48, a RAM 50, an input interface 52, and an output interface 54. The CPU 46 is a program stored in advance in the ROM 48. To process the input signal input through the input interface 52 according to the above and to obtain the target output torque T _e ^* to the fuel injector 16 through the output interface 54. And represents the control amount for controlling the output torque of the engine 10 to the input interface 40 in the first control device 32. Is output.

FIG. 3 is a functional block diagram showing a control configuration in the first control device 32 and the second control device 44, and
In block 60, the output torque of the transmission, in other words, the required driving torque T _{o of the} vehicle in response to the driver's request is calculated based on the accelerator operation signal A _cc and the vehicle speed V from the relationship obtained in advance. The relationship used at this time is obtained in advance so as to realize the driver's acceleration or deceleration request, and is stored in advance in the form of a data map or a function. In the second block 62 and the third block 64, a target speed ratio from previously obtained relationship in order to realize a driving torque T _o determined in the first block 60 e ^* and the target engine output torque T _e ^*
Are required respectively. Such a relationship is stored in advance in the case where a power selection drive that emphasizes drivability, power travel, economy travel that emphasizes economy, and a travel selection switch that selects normal travel are provided. A predetermined relationship is selected from the relationships. The engine output torque T _e ^* determined in the third block 64 is supplied to the second control device 44.

The second controller 44 determines the fuel injection amount so that the target engine output torque T _e ^* determined in the third block 64 is realized, and the fuel injection is performed so that the fuel is injected at the fuel injection amount. According to quantity Is supplied to the fuel injection device 16. Second control device
When a fuel cut signal F, which will be described later, is supplied, 44 determines the fuel injection amount to be zero and shuts off the fuel supplied from the fuel injection device 16 to the engine 10. That is, the first
The control device 32 and the second control device 44 form a fuel cut device. In the second control device 44, the cooling water temperature of the engine 10, the actual rotation speed of the engine 10,
Based on information that represents atmospheric pressure, etc. Is corrected. When the engine 10 is a gasoline engine, the second control device 44 determines the fuel amount, the intake air amount, the ignition timing, etc., and the air-fuel mixture is determined by the fuel amount and the intake air amount thus determined. The ignition timing is controlled while being supplied to the engine 10.

In the divider 65, the actual speed ratio e (= No from the input shaft rotation speed N _i and the output shaft rotation speed N _o of the belt type continuously variable transmission 14 is calculated.
/ Ni) is calculated. Further, the subtractor 66 obtains a deviation Δe between the target speed ratio e ^* determined in the second block 62 and the actual speed ratio e. In the speed ratio control block 68, the deviation Δe is calculated according to a predetermined control formula.
There is determined the controlled variable V _a is such that the zero, the controlled variable V _a
In response to this, the flow control servo valve 28 is operated.

Fourth for determining the fuel cut lower limit rotation speed N _f
In block 70, the fuel cut lower limit rotation speed N _f is determined from the previously determined relationship shown in FIG. 4 based on the shift position SF and the vehicle speed V, and the fuel cut lower limit rotation speed N _f and the actual fuel cut lower limit rotation speed N _f are determined. The difference ΔN from the engine rotation speed N _e is obtained by the subtractor 72. Then, in the fuel cut control block 74, the fifth
From the relationship obtained in advance shown in the figure, it is judged whether or not it is the fuel cut region based on the accelerator signal A _cc and the deviation ΔN, and if it is the fuel cut region, the fuel cut signal F is set to the second control device. 44 and the fuel cut transmission torque control block 76. The transmission torque control block 76 for fuel cut is
From the pre-determined relationship shown in FIG. 6, the control amount ΔG _f during fuel cut is determined based on the fuel cut signal F and the shift position signal SF and output to the adder 78.
The block 76 also has a timing control function of keeping the control amount ΔG _f for a predetermined delay time T _D when the fuel cut signal F is eliminated. Output from the adder 78 to the clutch control block 80 Is supplied, but the control amount ΔG _f for fuel cut is zero during non-fuel cut, and during fuel cut Is zero, the clutch control block 80 is output from the second control device 44 during normal traveling. Based on the above, the clutch transmission torque _Tc of a necessary and sufficient value that exceeds the output torque of the engine by a predetermined amount is determined, and the exciting current for obtaining this transmission torque _Tc is supplied from the drive circuit 29 to the magnetic powder type electromagnetic clutch 12. Supply. Also, during fuel cut, the control amount ΔG _f determined for fuel cut
Based on the above, the clutch transmission torque T _c is determined, and an exciting current is supplied to the magnetic powder type electromagnetic clutch 12 so as to obtain this transmission torque T _c . Incidentally, in the magnetic powder type electromagnetic clutch 12, when a slight slip is generated in order to absorb torque fluctuations of the vehicle at the time of starting the vehicle or where the slip is required, since a separately prepared control algorithm is used, The clutch transmission torque T _c is not necessarily proportional to the fuel injection amount.

The transmission capacity control block 82 includes a clutch control block 80.
The line hydraulic pressure supplied to the output side hydraulic actuator is adjusted based on the relationship determined in advance based on the clutch transmission torque _Tc output from the motor and the actual speed ratio e. This relationship is preliminarily obtained so that a narrow pressure on the transmission belt 22 is necessary and sufficient, and the line hydraulic pressure is required and sufficient within a range where slippage of the transmission belt 22 does not occur. Unnecessary power loss of the device is eliminated.

The signals representing the operating states of the engine 10 and the belt type continuously variable transmission 14 are used as correction parameters when determining the drive torque T _c in the first block 60, and the speed ratio control block 68 is also used. Is used as a correction parameter when determining the controlled variable V _a .

FIG. 1 is a flow chart for explaining an example of the control operation of the first control device 32 and the second control device 44. In the figure, steps SS1 to SS9 are steps for explaining the operation of the first control device 32, and ST1 to ST3 are steps for explaining the operation of the second explanation device 44.

First, the accelerator operation amount A _cc and the vehicle speed V is read in step SS1, the transmission output torque from the previously obtained relationship in step SS2, that is, the driving torque T _o of the vehicle is determined. In step SS3, the drive torque T _o optimal for obtaining the target speed ratio e ^* and the optimal target engine output torque T _e ^* is calculated from the previously obtained relationship. The target engine output torque T _e ^* obtained in step SS3 is supplied to the second control device 44.

Then, step SS4 is executed to set the target speed ratio e ^*.
The controlled variable V _a to the flow rate control servo valve 28 is calculated to obtain the same speed ratio e and. This calculation routine is executed according to the steps shown in FIG. 7, for example. First, step SU1 is executed so that the input shaft rotation speed N _i and the output shaft rotation speed N _{o of} the belt type continuously variable transmission 14 are _detected by the rotation sensor 24 and the rotation sensor 24.
In addition to being read based on the output signal of 26, step SU2 is executed, and the actual speed ratio e (= N _o / N _i ) of the belt type continuously variable transmission 14 is changed to the input shaft rotation speed N _i and the output shaft rotation. Calculated based on velocity _No. And step SU3
There is running, the control amount V _a on the basis of the control formula shown in the actual speed ratio and e between the target speed ratio e ^* following formula (1) is calculated.

V _a = K (e ^* −e) (1) Returning to FIG. 1, the fuel cut signal F determination routine of step SS5 is executed to determine whether the fuel cut signal F is in the fuel cut region. If it is in the area, the content of the fuel cut signal F (flag) is determined to be "1". This fuel cut signal F determination routine is performed, for example, according to the steps shown in FIG. That is, step SV1 is executed, and based on the shift position signal SF and the vehicle speed V, from the relationship shown in FIG.
The fuel cut lower limit rotation speed N _f is calculated. Then, step SV2 is executed to calculate the difference Δ between the actual engine speed N _e and the fuel cut lower limit engine speed N _f.
N is required. Next, step SV3 is executed to determine whether or not the vehicle is in the fuel cut region based on the relationship shown in FIG. 5 from the ΔN and the accelerator operation amount A _cc ,
When it is in the fuel cut area, the content of the signal F is "1", but when it is not in the fuel cut area, the content of the signal F is "0".

On the other hand, as shown in FIG. 1, in the second controller 44, step ST1 is executed to read the target engine output torque T _e ^* and the fuel cut signal F, and step ST2 is executed to execute the non-fuel control. When cutting (F =
0) is the fuel injection amount for obtaining the target engine output torque T _e ^* from the target engine output torque T _e ^* and the engine operating conditions. Is calculated. However, during fuel cut (F = 1)
Is the fuel injection amount Is zero. Then, step ST3 is executed, and it is determined in step ST2. Is output to the fuel injection device 16.

In the first control device 32, the fuel injection amount obtained in the second control device 44 The clutch transmission torque T _c is calculated based on That is, the clutch transmission torque _Tc calculation routine of step SS6 is executed according to the steps shown in FIG. 9, for example. That is, in step SW1, the value of the control amount ΔG _f during fuel cut is determined based on the relationship shown in FIG. 6 from the fuel cut signal F and the shift position signal SF. The value A of the control amount ΔG _f at the time of fuel cut may be a constant value within a range in which a transmission torque larger than the value required to restart the engine 10 can be obtained, but preferably from the relationship shown in FIG. It is determined based on the input shaft rotation speed N _i of the belt type continuously variable transmission 14. Relationship shown in FIG. 11, but taking into account the frictional torque loss of the engine are those necessary and sufficient value for engine restart have been determined in advance so as to obtain, in particular, N _i is idling rotation When the speed is lower than the speed, the torque transmitted to the engine 10 is determined to be sufficiently small under the condition that the torque is restarted to return the engine to its idle state. Resistance is reduced as much as possible, and restart shock is also reduced. The control amount ΔG _f on the fuel cut side obtained from the relationship in FIG. 11 is Is directly related to the clutch transmission torque T _c, and the relationship in FIG. 11 is obtained in consideration of the friction loss torque of the engine, the clutch transmission torque T _c is Input shaft speed N _i and engine
It can be considered that the friction loss torque of 10 is substantially obtained. Then, in step SW2, it is determined by the second control device 44. Is read, and from the control formula (2) predetermined in step SW3 The clutch transmission torque T _c is determined based on the control amount ΔG _f during fuel cut.

Returning to FIG. 1, in the subsequent step SS7, the actual speed ratio e and the clutch transmission torque T _c are read, and in step SS8, the control amount V _L supplied to the pressure control servo valve 30 is a predetermined control formula ( It is calculated from 3). This control formula (3) is set so that the tension of the transmission belt 22 is optimized, and the narrow pressure on the transmission belt 22 is reduced within a range where the transmission belt 22 does not slip.

V _L = f (e, T _c ) ... (3) Then, step SS9 is executed and the controlled variables V _a , V _L , T _c
Is output, flow control servo valve 28, pressure control servo valve
30 and the magnetic powder type electromagnetic clutch 12 are controlled.

As described above, according to the present embodiment, when it is determined in step SS5 that the fuel cut range is within (F = 1), the engine 10 is restarted during the fuel cut in step SW1. The control amount ΔG _f representing the transmission torque for slipping the magnetic powder type electromagnetic clutch 12 is determined within a range where a transmission torque larger than the required value is obtained, and the magnetic powder is transferred at the transmission torque T _c according to the magnitude of the control amount ΔG _f. The electromagnetic clutch 12 transmits power. Therefore, at the time of fuel cut, the rotation based on the running force of the vehicle is transmitted to the engine 10 through the magnetic particle type electromagnetic clutch 12 and the engine 10 is driven by the vehicle, so as shown in FIG. The speed N _f can be set as low as possible in comparison with the conventional value N _f ′. Therefore, the
The fuel cut range is expanded only in the area shown by W in FIG. 10, and the running fuel efficiency of the vehicle is greatly improved.

Moreover, since the transmission torque during fuel cut continues for a certain delay time T _D after the engine speed falls below the fuel cut lower limit rotation speed N _f ,
There is an advantage that 10 restarts can be obtained more reliably.

Further, according to the present embodiment, as shown in FIG. 6, when the shift lever is in the neutral range, the relatively high fuel cut lower limit rotation speed N _f , which is the same as the conventional one, is determined. Even in the neutral state in which 12 is not engaged, engine stall is preferably prevented.

Further, according to the present embodiment, in the state where the shift lever is operated in the D (R) range such as the drive (D) range, the fuel cut lower limit rotation speed N _f is as shown in FIG. Since it is set high in the vicinity of substantially zero (ultra low vehicle speed), there are advantages that the engine can be restarted reliably and the restart shock can be eliminated.

Further, in the D / R range operating state, the fuel cut lower limit rotation speed N _f is set to be lower as the vehicle speed becomes lower as a whole as shown in FIG. 4, which is an advantage that the range of fuel cut is further expanded. There is. The fuel cut lower limit rotation speed _Nf is set to be lower than the idle rotation speed of the engine and higher than the restartable rotation speed of the engine.

Further, according to this embodiment, as shown in FIG.
Even if the accelerator operation amount A _cc is not zero, if the difference between the actual engine rotation speed N _e and the fuel cut lower limit rotation speed N _f becomes large, the fuel cut will be executed, so the fuel cut will be further executed. There is an advantage that the area is expanded and the fuel efficiency of the vehicle is improved. In this case, instead of the relationship of FIG. 5, the engine rotation speed N _e and the accelerator operation amount A
_You may use the relationship which determines a fuel cut area | region from _cc .

Further, according to the present embodiment, the control amount ΔG _f used when determining the transmission torque T _c (= C · ΔG _f ) during fuel cut.
(= A) is a belt type continuously variable transmission based on the relationship shown in FIG. 11 which was previously obtained in consideration of the friction loss torque of the engine.
Based on the input shaft rotation speed N _i of 14, the larger the smaller N _i is so that the rotation speed and torque at restart are necessary and sufficient, the larger the value is determined. (Resistance) is made as small as possible, and shocks at the time of restart are alleviated.

Further, the control device of the present embodiment is composed of the first control device 32 and the second control device 44, and the target output torque T _e ^* that represents the optimum output torque of the engine determined by the first control device 32 ^. Is supplied to the second control device 44, while the fuel injection amount representing the output torque of the engine 10 obtained by the second control device 44, that is, Is supplied to the first control device 32, so that the engine 10, the magnetic powder type electromagnetic clutch 12, and the belt type continuously variable transmission 14 are divided according to the driving state of the vehicle, although they are divided into two control devices. It is optimally controlled comprehensively.

If the engine rotation sensor 27, the engine water amount sensor, etc. supply a signal to the second control device 44, the second control device 44 has its own sensor. Compared with the case of determining, the accelerator pedal sensor, the vehicle speed sensor, etc. are saved, and the device becomes inexpensive.

Further, the control device of the present embodiment is exclusively a belt type continuously variable transmission.
14 and the first control device 32 for controlling the magnetic powder type electromagnetic clutch 12, and the second control device 44 for exclusively controlling the output torque of the engine 10, the second control device 44 is A conventional control computer for controlling the output of the engine can be used, which also has the advantage that the device is inexpensive and system development is easy.

Further, since the first control device 32 and the second control device 44 are independently controlled, the program configuration is simpler than that of a control device using a single CPU, and a CPU capable of high-speed operation is specially designed. It does not need to be used for.

The application example of the present invention has been described above with reference to the drawings.
The present invention also applies to other aspects.

For example, in the above-described embodiment, the magnetic powder type electromagnetic clutch 12
However, a single plate electromagnetic clutch or a fluid clutch with a direct coupling clutch may be used.
In short, any clutch can be used as long as engagement control is possible during fuel cut.

Further, the lower limit rotational speed of the fuel cut is determined based on the traveling speed of the vehicle and the operation position of the shift lever as shown in FIG. 4, but is related to the accelerator operation amount and the operating state of the air conditioner. It may be decided to change.

It should be noted that the above is merely an application example of the present invention, and the present invention can be variously modified without departing from the spirit thereof.

[Brief description of drawings]

FIG. 1 is a flow chart for explaining the operation of the first control device and the second control device of FIG. FIG. 2 is a block diagram showing the structure of a control device to which the present invention is applied.
FIG. 3 is a functional block diagram showing a control configuration of the control device shown in FIG. FIG. 4 is a diagram showing the relationship used in obtaining the fuel cut lower limit rotation speed in FIG. FIG. 5 is a diagram showing a relationship used in determining whether or not the fuel cut region is in FIG. FIG. 6 shows the control amount ΔG _f for fuel cut in FIG.
It is a figure which shows the relationship for determining. FIG. 7 is a flowchart showing the flow rate control servo valve control amount calculation routine of FIG. FIG. 8 is a flow chart showing the fuel cut signal determination routine of FIG. FIG. 9 is a flowchart showing the clutch transmission torque calculation routine of FIG. FIG. 10 is a time chart showing the operation of the control device shown in FIG. FIG. 11 is a diagram showing the relationship used in the clutch transmission torque determination routine of FIG. 10: Engine 12: Magnetic powder type electromagnetic clutch (engagement controllable clutch) 32: First control device (fuel cut device) 44: Second control device (fuel cut device)

Claims (3)

[Claims] 1. A fuel cut device for shutting off fuel to be supplied to the engine until the rotation speed of the engine falls below a predetermined fuel cut lower limit rotation speed when the vehicle is decelerated, and the power of the engine is engaged. A control method for a vehicle, which transmits to a transmission and a drive wheel via a controllable clutch, wherein the clutch is in a half-engaged state while fuel to be supplied to the engine is interrupted by the fuel cut device. A method of controlling a vehicle equipped with a fuel cut device, wherein the clutch is slipped in a range in which a transmission torque larger than a value required to restart the engine is obtained. 2. The fuel cut device according to claim 1, wherein the clutch is controlled so that a torque that increases as the input shaft rotation speed of the transmission becomes lower is transmitted. Vehicle control method. 3. A state in which the clutch transmits power at a transmission torque before the start of fuel cutoff after a predetermined delay time has elapsed when the fuel cut device has stopped cutting off fuel to be supplied to the engine. A method for controlling a vehicle equipped with the fuel cut device according to claim 2, wherein the fuel cut device is returned to the vehicle.