JP3453885B2 - Engine control device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine control device, and more particularly, when an engine brake control condition is determined,
The present invention relates to an engine control device that secures an engine braking effect according to an accelerator operation amount except when the accelerator is fully closed.

[0002]

2. Description of the Related Art In the engine of this vehicle, in order to perform a so-called eco-run operation in order to reduce fuel consumption, the engine is automatically stopped when an eco-run operation determination is established during traveling. Some are equipped with an engine stop starter for starting control.

Some engines mounted on vehicles have a continuously variable transmission (CVT, also referred to as "continuously variable transmission") as a transmission equipped with a starting clutch. This continuously variable transmission continuously changes the gear ratio by changing the radius of gyration of a belt wound around a driving pulley and a driven pulley.

In order to reduce fuel consumption in an engine to which this continuously variable transmission is connected, for example, the engine is stopped when the vehicle is stopped, or the starting clutch is disengaged while the vehicle is running. Engine is stopped.

An example of the engine control device is Japanese Patent Laid-Open No.
There is one disclosed in Japanese Patent Publication No. 4-77727. The throttle control device disclosed in this publication is an electronically controlled throttle actuator that adjusts the throttle opening of a throttle valve arranged in an intake passage based on an operation amount of an accelerator pedal, and an electronically controlled throttle actuator that is operated by a brake device. Regardless of the above, the intake passage forced fully closed state that forces the intake passage to be fully closed and the operation for starting the start release the intake passage forced fully closed state based on the operation of the brake device before releasing the brake. When the electronically controlled throttle actuator is hindered, this hindrance is surely dealt with and it is possible to start on a slope.

Further, there is one disclosed in Japanese Utility Model Publication No. 2-13730. An intake throttle control device for a diesel engine disclosed in this publication includes an exhaust throttle valve that opens and closes an exhaust passage of the engine, and an intake throttle valve that opens and closes the intake passage in a diesel engine that closes the exhaust throttle valve during exhaust braking. , And a control device for controlling the opening and closing of the intake throttle valve so that the negative pressure in the intake passage downstream of the intake throttle valve is within a predetermined range during warm-up when the engine speed is below a predetermined speed or when the heater for heating is operating. The opening degree of the intake throttle valve is controlled to be maintained at a constant value, and the opening degree of the intake throttle valve is maintained at a constant opening degree when the engine speed is at least equal to or higher than the exhaust speed. While reducing the blowback of intake air due to the exhaust throttle, it also prevents engine misfire due to excessive throttle of intake air during warm-up or heating and deterioration of warm-up heating performance due to insufficient throttle. That.

[0007]

By the way, in the conventional engine control device, generally, the fuel cut control for stopping the fuel supply when the throttle is fully closed is used to enhance the engine braking effect.

Further, in a conventional engine control device, there is one that adopts an eco-run operation in which the starting clutch is released when a predetermined condition is satisfied, and the air flow rate is reduced regardless of the depression state of the accelerator pedal for idle operation. is there.

[0009] For reference, the patent applicant has already completed the application of an eco-run operation system of an engine stop method which is an idle operation method or another method.

There are the following five methods for determining the state for performing the eco-run operation, that is, the eco-run operation determination policy. , When the accelerator is fully closed (normal clutch control is performed and fuel stop control is performed), when the accelerator is fully closed (release the starting clutch at low vehicle speed to prepare for vehicle stop), and when the accelerator is low (accelerator for vehicle speed) The eco-run operation is performed at a generated torque of 0 kgm according to the operation amount.) During deceleration travel (eco-run operation is performed by determining the driver's deceleration travel intention based on the throttle opening relative to the vehicle speed and the vehicle deceleration). During constant speed running (eco-run operation is performed by determining the driver's willingness to run at constant speed based on the throttle opening relative to the vehicle speed and the deceleration of the vehicle.)

Incidentally, the one for performing normal clutch control is
Only the state of.

As a result, when the conventional fuel supply is stopped, the throttle valve is closed, that is, fully closed, and the pumping loss becomes maximum (see FIG. 8), which corresponds to the driver's intention to decelerate the engine brake. There is an inconvenience that it cannot be done and it is disadvantageous in practical use.

Further, as compared with the throttle fully closing operation in the fully closed state of the throttle valve described above, the fuel supply is restarted and the engine generated torque sharply increases (absorption torque sharply increases) only by slightly opening the throttle valve. Therefore, the engine braking effect is sharply reduced, and it is not possible to make fine engine braking adjustments.

The state of the absorption torque is a state in which the loss torque is larger than the torque generated by the combustion.

Further, when the clutch is disengaged by the eco-run control, the engine brake cannot be obtained regardless of the throttle opening, and the driver's intention to decelerate the engine brake cannot be met.

Furthermore, although the above-described system for the purpose of saving fuel consumption has heretofore existed, there is a disadvantage that the engine braking effect cannot be improved.

Now, a conventional fuel supply stop control device will be described.

As shown in FIG. 14, the fuel supply stop control system includes an accelerator pedal operation determining means for determining an idle switch, an engine rotational speed detecting means for detecting an engine rotational speed, a signal from the accelerator pedal operating determining means, and an engine. It has an engine control unit 524 for inputting a rotation speed signal and an injector 540 connected to this engine control unit 524.

The control of the general fuel supply stop control device will be described with reference to the flowchart of FIG. When the control program starts (602), it is determined whether the idle switch is in the ON state (604).

If the determination (604) is YES, it is determined whether the fuel supply is stopped (606).
When the determination (604) is NO, the fuel supply (612) is performed.

When the determination as to whether the fuel supply is stopped (606) is NO, the engine speed Ne and the fuel supply stop start NeTR5 are compared and determined (608).
If the determination (606) is YES, the engine speed Ne and the fuel supply stop end NeTR6 are compared and determined (610).

In the comparison judgment (608) between the engine speed Ne and the fuel supply stop start NeTR5, if Ne ≦ NeTR5, the fuel supply is switched to the fuel supply (612), and if Ne> NeTR5, the fuel supply is stopped. The process moves to (614).

Further, in the comparison judgment (610) of the engine speed Ne and the fuel supply stop completion NeTR6, if Ne <NeTR6, the fuel supply is switched to the fuel supply (612), and if Ne ≧ NeTR6, the fuel is stopped. The supply is stopped (614).

Fuel supply (612) and fuel supply stop (6)
After the processing of 14), the control program ends (616).

The loop operation by the above-mentioned control program is performed every minute time, and is controlled by the presence / absence of accelerator pedal operation by the driver (using an idle switch or the like) and the engine speed. The eco-run control when the accelerator is fully closed uses fuel supply stop control.

[0026]

Therefore, in order to eliminate the above-mentioned inconvenience, the present invention is provided with a throttle actuator for adjusting the intake flow rate supplied to the engine, and the accelerator operation amount and the engine rotation except when the accelerator is fully closed. Depending on the number, it is determined whether or not the engine brake control is being performed, and when this determination is established, the engine speed and the engine brake control escape trigger are compared, and the engine speed is equal to or lower than the engine brake control escape trigger. In the case of, it is determined that the engine brake control condition is not satisfied, and when the engine speed is higher than the engine brake control escape trigger, it is determined that the engine brake control condition is satisfied, and the engine brake control is being performed. If the judgment is not satisfied, the engine speed and engine brake If the engine speed is equal to or higher than the engine brake control entrance trigger, it is determined that the engine brake control conditions are satisfied, and the engine speed is the engine brake control entrance trigger. When the engine brake control condition is not satisfied, when the engine brake control condition is satisfied, the fuel supply to the engine is stopped and the throttle actuator is operated to operate the intake air flow rate to the engine. Is provided, and control means is provided for controlling to ensure the engine braking effect according to the accelerator operation amount.

A throttle actuator for adjusting the flow rate of intake air supplied to the engine and a clutch for electronically adjusting the torque capacity are provided so as to adjust the accelerator operation amount and the engine speed except when the accelerator is fully closed. , It is determined whether or not the engine brake control, during the establishment of this determination, the engine speed and the engine brake control escape trigger are compared, if the engine speed is equal to or lower than the engine brake control escape trigger, If it is determined that the engine brake control condition is not satisfied, and the engine speed is higher than the engine brake control escape trigger, it is determined that the engine brake control condition is satisfied, and it is determined whether the engine brake control is being performed. , If the judgment is not successful, the engine speed and engine break If the engine speed is equal to or higher than the engine brake control entrance trigger, it is determined that the engine brake control conditions are satisfied, and the engine speed is less than the engine brake control entrance trigger. In this case, it is determined that the engine brake control condition is not satisfied, and when the engine brake control condition is satisfied, the fuel supply to the engine is stopped and the throttle actuator is operated to adjust the intake air flow rate to the engine. In addition, a control means for controlling the clutch to ensure the engine braking effect according to the accelerator operation amount is provided.

[0028]

According to the invention as described above, when the determination of the engine brake control condition according to the accelerator operation amount and the engine speed except when the accelerator is fully closed is satisfied, the control means stops the fuel supply to the engine. , The throttle actuator is operated to adjust the intake air flow rate to the engine to ensure the engine braking effect according to the accelerator operation amount.

Further, when the determination of the engine brake control condition according to the accelerator operation amount and the engine speed except when the accelerator is fully closed is satisfied, the control means stops the fuel supply to the engine and operates the throttle actuator. The intake air flow rate to the engine is adjusted and the clutch is controlled to secure the engine braking effect according to the accelerator operation amount.

[0030]

Embodiments of the present invention will be described in detail below with reference to the drawings.

1 to 13 show an embodiment of the present invention. In FIG. 2, 2 is an engine mounted on a vehicle (not shown), 4 is a control device for the engine 2, 6 is an intake manifold, 8 is an intake passage, 10 is a throttle valve, 12
Is an air cleaner.

A transmission (continuously variable transmission: CVT) 14 having a transmission unit (not shown) is connected to the engine 2. The transmission 14 includes a drive pulley, a driven pulley,
It has a belt wound around the drive pulley and the driven pulley.

Here, the transmission section (not shown) will be briefly explained. The drive pulley includes a drive shaft, a drive-side fixed pulley portion integrally provided on the drive shaft, and an axially movable movement on the drive shaft. And a drive-side movable pulley piece provided so as not to rotate.

The driven pulley includes a driven shaft arranged substantially parallel to the drive shaft, a driven-side fixed pulley portion integrally provided on the driven shaft, and an axially movable shaft. And a driven-side movable pulley piece provided so as not to rotate.

A starting clutch 16 for electronically adjusting the torque capacity is provided between a crank shaft (not shown) of the engine 2 and a drive shaft (not shown) of the transmission 14, for example, in the transmission 14.
Is provided. Further, the engine 2 is provided with an engine stop / start device 18. The engine stop / start device 18, when the predetermined stop condition and start condition are satisfied,
The control means 20 automatically stops and starts the engine 2.

That is, as shown in FIG. 3, in the engine stop / start device 18, the control means 20 has the transmission control unit 2.
2 and an engine control unit 24. When the transmission control unit 22 outputs an engine stop request signal to the engine control unit 24, the engine control unit 24 stops the operation of an injector (not shown). While stopping the fuel supply to the engine 2 and outputting an ignition control signal to a spark plug (not shown), when the transmission control unit 22 outputs a start signal to a starter (not shown), the starter operates and the engine 2 starts. It is a thing.

More specifically, in the engine stop / start device 18, the engine 2 is normally controlled by operating the injector and the spark plug normally without outputting the engine stop request signal during normal operation of the engine 2. , The starter has stopped. Further, while the engine 2 is stopped, the engine stop request signal is output, the operation of the injector and the spark plug is stopped, and the starter is stopped. Furthermore, at the time of starting the engine 2, it is time to escape from the so-called eco-run operation in which the fuel consumption is reduced, the engine stop request signal is not output, and the injector and the spark plug are normally operated to operate the engine 2 normally. Control and activate the starter. The starter can be operated at the time of manual start operation.

In the control means 20, as shown in FIG.
On the output side, an engine stop / start device 18 for stopping the operation of the injector or for operating the starter and a throttle actuator 26 composed of a motor for operating the throttle valve 10 are connected, and the transmission 1
An output signal path for adjusting the clutch of the starting clutch 16 on the fourth side and an output signal path for adjusting the gear ratio of a transmission unit (not shown) of the transmission 14 are provided.

This gear ratio adjustment is electrically operated by the control means 20 in order to properly control the gear shift of the transmission 14 when the clutch 16 is disengaged while the vehicle is traveling. Is.

As shown in FIG. 2, the control means 20 has a throttle opening sensor (not shown) for detecting the throttle opening (θ, theta) of the throttle valve 10 on the input side and a crankshaft (not shown). ) As an engine rotation speed (Ne), an engine rotation speed sensor (not shown), and a rotation speed of a drive shaft (not shown) of the transmission 14 as a transmission input rotation speed (not shown). Sensor and driven shaft of transmission 14 (not shown)
A vehicle speed sensor (not shown) that detects the rotation of the vehicle as the vehicle speed,
An eco-run switch (not shown), a shift position switch (not shown), a power mode switch (not shown), and other detection means are in communication with each other.

An intake air flow rate adjusting means 28 for adjusting the intake air flow rate supplied to the engine 2 is connected to the control means 20, and according to the accelerator operation amount and the engine speed except when the accelerator is fully closed. It is determined whether the engine brake control is being performed, and when this determination is established, the engine speed is compared with the engine brake control escape trigger, and if the engine speed is equal to or lower than the engine brake control escape trigger, It is determined that the engine brake control condition which is the absorption torque region of No. 2 is not satisfied, and when the engine speed is higher than the engine brake control escape trigger, it is determined that the engine brake control condition is satisfied, and the engine brake Depending on whether or not control is in progress, if the determination is not successful, the engine speed and engine When the engine speed is equal to or higher than the engine brake control entrance trigger, it is determined that the engine brake control condition that is the absorption torque region of the engine 2 is satisfied, and the engine speed is compared with the control entrance trigger. Is less than the engine brake control admission trigger, it is determined that the engine brake control condition is not satisfied, and when the engine brake control condition is satisfied, the fuel supply to the engine 2 is stopped and the intake flow rate adjustment is performed. It has a configuration in which the means 28 is operated to adjust the flow rate of intake air to the engine 2 and control is performed to ensure the engine braking effect according to the accelerator operation amount.

Further, the control means 20 stops the fuel supply to the engine 2 and operates the intake flow rate adjusting means 28 to adjust the intake flow rate to the engine 2 when the determination of the engine brake control condition is satisfied. In addition, it also has a function of controlling the clutch 16 that electronically adjusts the torque capacity to ensure the engine braking effect according to the accelerator operation amount.

More specifically, the intake flow rate adjusting means 28
Is composed of, for example, a throttle actuator 26 which is connected to the throttle valve 10 to open and close, and is driven by a control signal from the control means 20.
Further, the operation amount of the accelerator pedal 30 of the vehicle (not shown),
That is, the accelerator operation amount sensor 32 for detecting the accelerator operation amount is provided, and the accelerator operation amount sensor 32 is provided.
Is connected to the control means 20, and the accelerator operation amount sensor 32 detects an accelerator operation amount which is a driving operation state which is a driver's intention to decelerate.

Explaining the case where the function of the present invention is combined with the conventional fuel supply stop and clutch disengagement eco-run operation, in the region indicated by the symbol t in FIG. 7, the driver often intends to decelerate, Normal clutch control is performed with the fuel supply stopped. Then, the throttle valve 10 is opened by the throttle actuator 26, the pumping loss of the engine 2 during the fuel supply stop is adjusted, and the absorption torque is changed.

That is, in the normal clutch control state, the state where the fuel supply is stopped and the engine braking effect is obtained, which is obtained only when the throttle is fully closed, is realized during the operation of the accelerator pedal 30, and braking is performed as compared with the conventional case. The effect is enhanced. The engine braking effect during operation of the accelerator pedal 30 is a weak engine braking effect because the throttle valve 10 is opened.

Therefore, in the above t range, the throttle valve 10 is opened and control is performed to reduce the pumping loss of the engine 2.

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

When the program is started (102) in the control means 20, first, it is judged (104) whether or not the engine brake control condition is satisfied.

Whether or not the engine brake (or "emble") control condition is satisfied is determined as shown in FIG.

That is, in FIG. 4, when the engine brake control condition program is started (202), first, the accelerator operation amount from the accelerator operation amount sensor 30 and the engine rotation speed (Ne) from the engine rotation speed sensor (not shown) are shown. Is input, and it is determined from the map (204) whether the engine brake control is being performed (206).

If the result of this judgment (206) is YES,
The engine speed (Ne) and the engine brake control escape trigger (NeTR2) are compared and judged (208). When Ne> NeTR2, the engine brake control condition is satisfied (210), and the engine brake control condition program is set. End (216) and Ne ≦
In the case of NeTR2, the engine brake control condition is not satisfied (214), and the program of the engine brake control condition is ended (216).

If the result of the determination (206) is NO, the engine speed (Ne) and the engine brake control entrance trigger (NeTR1) are compared and determined (212).
When Ne ≧ NeTR1, the engine brake control condition is satisfied (210), the program of the engine brake control condition is ended (216), and N
When e <NeTR1, the engine brake control condition is not satisfied (214), and the program of the engine brake control condition is ended (216).

When the engine brake control condition is satisfied in the judgment (104) in FIG. 1, that is, when the determination is YES, the engine 2
The fuel supply to the engine is stopped (106), the normal clutch control (108) is performed, and the throttle valve control (110) according to FIG. 12 is performed.

When the engine brake control condition is not satisfied in the judgment (104), that is, when the condition is NO, it is judged whether or not the driving prohibition condition for reducing the fuel consumption, that is, the so-called eco-run prohibition condition is satisfied (104). To do.

Whether or not the eco-run prohibition condition is satisfied is determined as shown in FIG.

That is, in FIG. 5, when the program of the eco-run prohibition condition is started (302), first, it is judged whether or not an eco-run switch (not shown) is on (304).

If the result of this judgment (304) is YES,
The shift position switch (not shown) drives (D)
It is determined whether or not (306).

If the result of this judgment (306) is YES,
It is determined whether a power mode switch (not shown) is on (308).

If the judgment (308) is NO, it is judged that the eco-run prohibition condition is not satisfied (310).

On the other hand, if the judgment (304) is NO,
If NO in the judgment (306), the judgment (308)
If YES, it is determined that the eco-run prohibition condition is satisfied (312).

After the processing of the judgments (310, 312), the program of the eco-run prohibition condition is ended (31
4).

If it is determined in the determination (112) in FIG. 1 that the eco-run prohibition condition is satisfied, that is, if YES, the engine 2 is normally controlled (114) and the normal clutch control (1) is performed.
16), and the normal throttle valve control (11
Perform 8).

When it is judged in the judgment (112) that the eco-run prohibition condition is not satisfied, that is, NO, it is judged (120) whether or not the accelerator fully closed judgment condition is satisfied.

Whether or not the accelerator full-close determination condition in this determination (120) is satisfied is determined as shown in FIG.

That is, in FIG. 6, when the program for the accelerator full-closed judgment condition is started (402), first, it is judged whether or not the accelerator is fully closed (404),
If this determination (404) is YES, it is determined (406) whether the accelerator fully closed condition is satisfied, and the determination (4
If 04) is NO, it is determined that the accelerator fully closed condition is not satisfied (408).

In the above determination (406), when the accelerator full-close condition is not satisfied, that is, when the condition is NO, that is, when the normal clutch control and fuel stop control are not performed, the engine speed (Ne) and the clutch release Ne trigger ( Ne
Make a comparison judgment (410) with TR3), and Ne> NeT
When R3, it is determined that the accelerator fully closed condition is satisfied (414), and when Ne ≦ NeTR3, it is determined that the accelerator fully closed condition is satisfied (416).

In the above determination (406), if the accelerator fully closed condition is satisfied, that is, if YES, a comparison determination (412) between the engine speed (Ne) and the normal clutch control Ne trigger (NeTR4) is made. Done, Ne>
In the case of NeTR4, it is determined that the accelerator fully closed condition is satisfied (414), and in the case of Ne ≦ NeTR4, it is determined that the accelerator fully closed condition is satisfied (416).

Then, each judgment (408, 414, 41)
After 6), the program for the accelerator full-closed determination condition is ended (418).

When it is judged in the judgment (120) of FIG. 1 that the accelerator fully closed condition of the accelerator fully closed judgment condition is satisfied, the fuel supply to the engine 2 is stopped (122) and the normal clutch control (124) is performed. , And the throttle valve 10
Is set to the fully closed state (126).

If it is judged at the judgment (120) in FIG. 1 that the accelerator fully closed condition of the accelerator fully closed judgment condition is satisfied, the fuel supply to the engine 2 is stopped (128) and the clutch is released (130). , And the throttle valve 10
Is in the fully closed state (132).

Further, when it is judged in the judgment (120) in FIG. 1 that neither the accelerator fully closed condition nor the accelerator fully closed condition is satisfied, it is judged whether the eco-run start condition is satisfied (134). I do.

The eco-run start condition in this judgment (134) is to judge the driver's deceleration intention from the throttle opening corresponding to the vehicle speed and the deceleration of the vehicle at the time of decelerating, or at the constant speed traveling. Is to determine the driver's intention to run at a constant speed from the throttle opening corresponding to the above and the deceleration of the vehicle.

If the eco-run start condition is satisfied in the determination (134), that is, if YES, the fuel supply to the engine 2 is stopped (136) and the clutch 16 is released (13).
8) so that the throttle valve 10 is fully closed (140).

When the eco-run start condition is not satisfied in the judgment (134), that is, when the condition is NO, the engine 2 is normally controlled (142), the normal clutch control (144) is performed, and the normal throttle valve is operated. It also controls (146).

The above processing (110, 118, 126, 13
2, 140, 146) followed by the program ending (1
48).

Explaining with reference to the time chart of FIG. 9, first, as shown in the time chart of FIG. 17, first, the engine stop eco-run operation is performed from the circled point a to the point b, and the accelerator is fully closed. The clutch 16 is released during the engine stop eco-run operation except the normal clutch control eco-run operation. Therefore, it is impossible for the driver to apply the engine brake even if the driver has a deceleration intention.

In the present invention, as shown in the time chart of FIG. 9, when the condition for discriminating that the driver has the intention of decelerating is satisfied, the eco-run driving is performed at the circled point d. Is released, normal clutch control is performed, and the throttle valve 10 is adjusted. Therefore, it is possible to apply the engine brake according to the accelerator pedal operation from the point e, and the braking effect is improved as compared with the eco-run operation in which the clutch is released.

Further, according to the present invention, it is possible to realize fine engine braking without supplying fuel to the engine 2 and to use the conventional eco-run operation together.

Generally, the torque generated by the engine 2 can be theoretically calculated by the heat value of the fuel. However, the following loss exists and the calculated value does not match. (1) Fuel failure loss (2) Heat conduction loss (3) Mechanical loss (mechanical loss) (4) Intake and exhaust loss

The pumping loss is included in the above item (4). This pumping loss is generated by the intake resistance generated by the operation of the throttle valve 10 in the intake stroke of the engine 2, and has the characteristic shown in FIG. 8 with respect to the throttle opening.

Further, the state where the engine 2 is in the absorption torque state means that the loss torque is larger than the torque generated by the combustion, and the engine torque becomes only the loss torque while the fuel supply is stopped. ), And the effect of pumping loss is particularly large.

Here, the difference between the engine brake control technology and the exhaust brake control technology will be described. While the engine brake control stops the fuel supply, the exhaust brake control does not supply the fuel. It is unquestioned.

In engine brake control,
While the throttle valve is arranged in the intake passage and the intake resistance is changed to adjust the engine braking, in the exhaust brake control, the exhaust resistance is increased to perform the engine braking. The exhaust resistance is increased by closing the exhaust passage with an exhaust throttle valve provided in the exhaust passage.

As a result, the intake flow rate adjusting means 28 can finely adjust the intake flow rate to the engine 2.
The pumping loss of the engine 2 can be reduced.

Further, by using the throttle actuator 26 as the intake flow rate adjusting means 28, the opening degree of the throttle valve 10 can be finely adjusted by the throttle actuator 26, and the intake flow rate to the engine 2 can be finely adjusted. The pumping loss of the engine 2 can be reduced.

Further, when the determination of the engine brake control condition is established, the fuel supply to the engine 2 is stopped and the intake flow rate adjusting means 28 is operated to adjust the intake flow rate to the engine 2 to adjust the engine brake according to the accelerator operation amount. By providing the control means 20 for controlling so as to secure the effect, it is possible to secure the engine braking effect according to the driving intention of the driver.

By performing the normal fuel control even while the accelerator pedal is being operated, it is possible to increase the usage of the engine brake, reduce the wear of the brake parts, and be economically and practically advantageous. ,
The intake flow rate can be finely adjusted, and the pumping loss of the engine can be reduced.

Furthermore, there is no fear that the drivability will deteriorate, which is advantageous in practical use.

Further, it is possible to improve the fuel saving characteristic by enabling fine engine braking without supplying fuel.

Furthermore, since it can be used in combination with the eco-run control such as the engine stop method and the idle operation method,
Usability can be improved.

Furthermore, since it can be realized by a slight change in the hardware and a slight change in the control program, there is no fear that the cost will be excessive, and it is economically advantageous.

When the determination of the engine brake control condition is established, the fuel supply to the engine 2 is stopped and the intake air flow rate adjusting means 28, which is the throttle actuator 2, is used.
6 is provided to adjust the intake air flow rate to the engine 2 and to control the clutch 16 so as to ensure the engine braking effect according to the accelerator operation amount. Also, according to the driver's willingness to travel, the eco-run control can be escaped to a normal clutch control, and the engine braking effect according to the accelerator pedal operation can be secured.

[0093]

As described in detail above, according to the present invention, the throttle actuator for adjusting the intake flow rate supplied to the engine is provided, and the throttle actuator is controlled according to the accelerator operation amount and the engine speed except when the accelerator is fully closed. It is determined whether the engine brake control is being performed, and when this determination is established, the engine speed is compared with the engine brake control escape trigger, and if the engine speed is equal to or lower than the engine brake control escape trigger, If it is determined that the brake control condition is not satisfied, and the engine speed is greater than the engine brake control escape trigger, it is determined that the engine brake control condition is satisfied, and by the determination whether the engine brake control is being performed, When the judgment is not successful, the engine speed and engine brake control entrance trigger If the engine speed is equal to or higher than the engine brake control entrance trigger, it is determined that the engine brake control condition is satisfied, and if the engine speed is lower than the engine brake control entrance trigger, When it is determined that the brake control condition is not satisfied, and when this engine brake control condition is satisfied, the fuel supply to the engine is stopped and the throttle actuator is operated to adjust the intake air flow rate to the engine, and the accelerator operation amount is adjusted. Since the control means for controlling so as to secure the engine braking effect according to the above is provided, the intake air flow rate to the engine can be finely adjusted by the throttle actuator, and the pumping loss of the engine can be reduced. Further, when the determination of the engine brake control condition is satisfied, the fuel supply to the engine is stopped, and the intake flow rate adjusting means is operated to adjust the intake flow rate to the engine to ensure the engine braking effect according to the accelerator operation amount. By providing the control means for controlling as much as possible, it is possible to secure the engine braking effect according to the driving intention of the driver. Then, by performing normal fuel control even while the accelerator pedal is being operated, it is possible to increase the usage status of the engine brake, reduce wear of the brake parts, and be economically and practically advantageous, and
The intake flow rate can be finely adjusted, and the pumping loss of the engine can be reduced. Further, there is no fear that the drivability will deteriorate, which is practically advantageous. Furthermore, fuel economy characteristics can be improved by enabling fine engine braking without fuel supply. In addition, it is possible to improve the usability because it can be used together with the eco-run control such as the engine stop method and the idle operation method. Furthermore,
Since it can be realized by a slight change in the hardware and a slight change in the control program, there is no fear that the cost will be excessive, and it is economically advantageous.

Further, a throttle actuator for adjusting the flow rate of intake air supplied to the engine is provided, and a clutch for electronically adjusting the torque capacity is provided, so that the amount of accelerator operation and the engine speed except when the accelerator is fully closed are set. , It is determined whether or not the engine brake control, during the establishment of this determination, the engine speed and the engine brake control escape trigger are compared, if the engine speed is equal to or lower than the engine brake control escape trigger, If it is determined that the engine brake control condition is not satisfied, and the engine speed is higher than the engine brake control escape trigger, it is determined that the engine brake control condition is satisfied, and it is determined whether the engine brake control is being performed. , If the judgment is not successful, the engine speed and engine break If the engine speed is equal to or higher than the engine brake control entrance trigger, it is determined that the engine brake control conditions are satisfied, and the engine speed is less than the engine brake control entrance trigger. In this case, it is determined that the engine brake control condition is not satisfied, and when the engine brake control condition is satisfied, the fuel supply to the engine is stopped and the throttle actuator is operated to adjust the intake air flow rate to the engine. In addition, the control means is provided to control the clutch to secure the engine braking effect according to the accelerator operation amount. Therefore, in addition to the above-mentioned effect, escape from the eco-run control according to the driver's willingness to drive. The normal clutch control to ensure the engine braking effect according to the accelerator pedal operation. Can.

[Brief description of drawings]

FIG. 1 is a control flowchart of an engine control device showing an embodiment of the present invention.

FIG. 2 is a system configuration diagram of an engine control device.

FIG. 3 is a system configuration diagram of an engine stop / start device.

FIG. 4 is a flowchart of engine brake control conditions for determining the t region of FIG.

FIG. 5 is a flowchart of eco-run prohibition conditions.

FIG. 6 is a flowchart of accelerator full-close determination conditions.

FIG. 7 is a diagram showing an eco-run control region based on a relationship between an accelerator operation amount and a vehicle speed.

FIG. 8 is a diagram showing a relationship between a throttle valve opening and pumping loss.

FIG. 9 is a time chart of engine control.

FIG. 10 is a diagram showing a relationship between engine rotation speed and engine generated torque.

FIG. 11 is a diagram showing an example of a trigger for performing engine brake control based on a relationship between an accelerator operation amount (throttle opening) and an engine rotation speed.

FIG. 12 is a diagram showing a throttle target value θ (theta) sp for throttle control during engine brake control from the relationship between engine speed and throttle opening.

FIG. 13 is a time chart of fuel stop control.

FIG. 14 is a configuration diagram of a fuel stop control system showing a conventional technique of the present invention.

FIG. 15 is a flowchart for fuel stop control.

FIG. 16 is a time chart of fuel stop control.

FIG. 17 is a time chart of engine control.

[Explanation of symbols]

2 engine 4 control device 8 Intake passage 10 Throttle valve 14 Transmission (continuously variable transmission: CVT) 16 Start clutch 18 Engine stop starter 20 Control means 22 Control unit for transmission 24 Engine control unit 26 Throttle actuator 28 Intake flow rate adjusting means 30 accelerator pedal 32 Accelerator operation amount sensor

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-6-87356 (JP, A) JP-A-3-194138 (JP, A) JP-A-2-64239 (JP, A) JP-A-6- 87355 (JP, A) Actual development Sho 59-100941 (JP, U) Actual development Sho 62-124252 (JP, U) Actual development Sho 63-96257 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) F02D 29/00 B60K 41/00

Claims (2)

(57) [Claims] 1. A throttle actuator for adjusting an intake air flow rate supplied to an engine is provided, and it is determined whether or not engine brake control is being performed according to an accelerator operation amount and an engine speed except when the accelerator is fully closed. When the engine speed is equal to or lower than the engine brake control escape trigger, it is determined that the engine brake control condition is not satisfied, and the engine speed is equal to or less than the engine brake control escape trigger. rotation
If the number is larger than the trigger for engine brake control escape
Determines that the engine brake control conditions are met.
And by determining whether in the engine brake control, determination at the time not satisfied, by comparing the trigger engine speed and the engine brake control admission, when the engine speed is greater than the trigger for the engine brake control admission , It is determined that the engine brake control conditions are satisfied, and the engine speed is set to the engine brake control entrance threshold.
If it is less than G, the engine brake control condition is not satisfied.
When the engine brake control condition is satisfied, the fuel supply to the engine is stopped and
An engine control device comprising: a control unit that operates the throttle actuator to adjust an intake air flow rate to the engine, and controls to ensure an engine braking effect according to an accelerator operation amount. 2. A throttle actuator for adjusting the flow rate of intake air supplied to the engine, and a clutch for electronically adjusting the torque capacity are provided, depending on the accelerator operation amount and the engine speed except when the accelerator is fully closed. ,
It is determined whether the engine brake control is being performed, and when this determination is established, the engine speed is compared with the engine brake control escape trigger, and if the engine speed is equal to or lower than the engine brake control escape trigger, It is determined that the brake control conditions are not satisfied, and the engine
The rotation speed is greater than the engine brake control escape trigger
In this case, it is determined that the engine brake control condition is satisfied.
When the determination is not satisfied, the engine speed and the engine brake control entrance trigger are compared, and when the engine speed is equal to or higher than the engine brake control entrance trigger, Determines that the engine brake control conditions are met, and the engine speed is set to the engine brake control entrance threshold.
In the case of less than moths, engine brake control condition is not satisfied
When the engine brake control condition is satisfied, the fuel supply to the engine is stopped and
An engine control device comprising a control means for operating the throttle actuator to adjust an intake air flow rate to the engine and controlling the clutch to ensure an engine braking effect according to an accelerator operation amount. .