JPH05180024A - Control device for engine - Google Patents

Abstract

PURPOSE:To prevent the speed change of an engine in which two throttle valves are provided in series, from being necessarily carried out, by controlling the opening degrees of the throttle valves so that the intake air volume is not affected by one of the throttle valves which is electrically controlled, during control of constant speed running CONSTITUTION:An intake passage 9 is provided therein with a mechanical throttle valve 12 which is opened and closed under control by an actuator 13 such as a servomotor or the like, and an electrical throttle valve 15 which is opened and closed under control by an actuator 14 in series, being arranged in the mentioned order from the upstream side. The opening degree of the electrical throttle valve 15 is adjusted in accordance with an opening degree of the mechanical throttle valve 12 in order to enhance the drivability such as acceleration feeling of the vehicle. Further, the mechanical throttle valve 12 is opened and closed under control by a constant speed running control device 32 during constant speed running. During constant speed running, the opening degree of the electrical throttle valve 15 is compensated in an opening direction in comparison with non-constant speed running, thereby it is possible to prevent insufficiency of engine output power.

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 in particular, a throttle valve which is opened and closed by an accelerator pedal and a throttle valve which is electrically opened and closed by an actuator are arranged in series in an intake passage. The present invention relates to an engine in which the opening degree of the former throttle valve is adjusted by a constant speed traveling control device so that the vehicle travels at a constant speed.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Patent Laid-Open No. 60-2774.
As shown in Japanese Patent No. 4 etc., in the intake passage of the engine,
A first throttle valve that opens and closes in conjunction with the accelerator pedal and a second throttle valve that opens and closes by driving an electrically operated actuator are arranged in series to enhance drivability such as a feeling of acceleration of the vehicle. For the purpose, a control device is known which controls the output torque of the engine by changing the opening of the second throttle valve according to the opening of the first throttle valve.

On the other hand, a constant speed running control device for keeping the speed constant in a vehicle equipped with an automatic transmission has been conventionally known. In this device, for example, the vehicle approaches an uphill road and the vehicle speed changes from a target value. When it decreases, first open the throttle valve opening to increase the engine output, and if the vehicle speed still decreases and falls below the range determined by the gear of the transmission, further increase the throttle opening to obtain the throttle opening. The shift position of the transmission set by the vehicle speed is downshifted to maintain the vehicle speed at the target value.

[0004]

When such a constant speed traveling control device is combined with an engine having a plurality of throttle valves as described above, the engine output is controlled by the first throttle valve which is interlocked with the accelerator pedal to keep the vehicle speed constant. It may be adapted to maintain the value. At that time, if there is an engine operating range in which the opening of the second throttle valve tends to close with respect to the first throttle valve, the first throttle valve is opened in an attempt to maintain the vehicle speed at the target value on an uphill road. Even if the degree of rotation is increased, the output torque of the engine does not increase to a required magnitude due to the influence of the second throttle valve having a small opening, and as a result, the throttle opening further increases and the automatic transmission The shift-down control is performed, and there is a problem that the shift shock at that time cannot be avoided.

The present invention has been made in view of the above circumstances, and an object thereof is to combine an engine having a plurality of throttle valves arranged in series in the intake passage with a constant speed traveling control device as described above. By changing the opening control of the throttle valve driven by the actuator, the throttle valve does not affect the intake air amount determined by the throttle valve that works with the accelerator pedal. The purpose is to prevent unnecessary shift shifting of the transmission due to insufficient output torque of the engine.

[0006]

In order to achieve the above object, according to the invention of claim 1, when the vehicle is controlled to run at a constant speed by the constant speed travel control device, the throttle valve driven by the actuator is opened. It was decided to correct the degree to the open side more than usual.

Specifically, according to the present invention, as shown in FIG. 1, a first throttle valve 12 that opens and closes in an intake passage 9 in conjunction with an accelerator pedal 10 and an actuator 14 are provided.
A second throttle valve 15 that is driven and opened / closed by is arranged in series, and the output torque is controlled by changing the opening of the second throttle valve 15 according to the opening of the first throttle valve 12. The engine 1 configured to do this is a prerequisite.

A constant speed running control means 32 for controlling the opening of the first throttle valve 12 so that a vehicle equipped with the engine 1 runs at a constant speed, and the constant speed running control means 32 are put into an operating state. At some time, the second throttle valve 1
The throttle opening correction means 40 is provided for correcting the opening degree of No. 5 in the opening direction as compared with the constant speed traveling control means 32 when it is not operated.

According to the second aspect of the present invention, there is provided throttle opening detecting means 33 for detecting the opening of the first throttle valve 12 which is interlocked with the accelerator pedal 10, and the throttle opening correcting means 40 is the throttle opening correcting means 40. Degree detecting means 33
When the opening degree of the first throttle valve 12 detected by the above changes in the opening direction by a predetermined value or more, the opening degree of the second throttle valve 15 is corrected in the opening direction according to the change amount. ..

[0010]

With the above construction, in the invention of claim 1, the opening of the first throttle valve 12 is controlled by the constant speed running control means 32 so that the vehicle runs at a constant speed, and the output of the engine 1 is controlled. The torque is changed. At this time, along with the operation of the constant speed traveling control means 32, the opening degree of the second throttle valve 15 is corrected by the throttle opening degree correction means 40 in the opening direction as compared with when the constant speed traveling control means 32 is not operated. It By correcting the opening degree of the second throttle valve 15, the throttle action of the intake air by the second throttle valve is suppressed, and the restriction of the intake air flow by the throttle valve 15 is removed.
The intake air amount is set by the opening degree of the first throttle valve 12 without being affected by the second throttle valve 15, and therefore the vehicle speed can be increased on the uphill road without greatly increasing the opening degree of the first throttle valve 12. Can be maintained at a constant value, and unnecessary gear shifting of the transmission can be suppressed.

According to the second aspect of the invention, when the opening of the first throttle valve 12 detected by the throttle opening detection means 33 changes by a predetermined value or more in the opening direction, the throttle opening correction means 40 causes First throttle valve 12
The opening degree of the second throttle valve 15 is corrected in the opening direction according to the change amount of the opening degree. Therefore, in addition to the same operational effect as the invention of claim 1, the second throttle valve 15 is operated under the condition that the opening degree of the first throttle valve 12 does not change in the opening direction by a predetermined value or more. Since the opening is not corrected, the output torque control of the engine 1 by the throttle valve 15 can be performed by utilizing the second throttle valve 15.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS. FIG. 2 shows the overall construction of an embodiment of the present invention. Reference numeral 1 denotes an engine mounted on a vehicle. This engine 1 is constructed by assembling a cylinder head 4 on a cylinder block 3 having a cylinder 2. A piston 5 is reciprocally fitted therein, and a space surrounded by the piston 5 and the cylinder head 4 in the cylinder 2 serves as a combustion chamber 6.

An intake port 7 and an exhaust port 16 communicating with the combustion chamber 6 are opened in the cylinder head 4.
The intake port 7 is opened and closed by an intake valve 8, and the exhaust port 16 is opened and closed by an exhaust valve 17. The intake port 7 constitutes a downstream end portion of an intake passage 9 for supplying intake air (air) to the combustion chamber 6 in the intake stroke, and the upstream end of the intake passage 9 is connected to an air cleaner (not shown). Intake air amount (intake amount) in the intake passage 9 immediately downstream of the air cleaner
An air flow meter (not shown) for detecting
In the intake passage 9 on the downstream side of the air flow meter, a mechanical throttle valve 12 as a first throttle valve that is connected to an accelerator pedal 10 by a connecting mechanism 11 and opens and closes in conjunction with the accelerator pedal 10, a servo motor, and the like. An electric throttle valve 15 as a second throttle valve that is driven to open and close by the actuator 14 is arranged in series in the order described from the upstream side. The mechanical throttle valve 12 is an actuator 1 including a servomotor or the like.
3 is also connected, and the actuator 13 adjusts the opening MTVO of the mechanical throttle valve 12. Also,
The electric throttle valve 15 has an opening ET of the electric throttle valve 15 for the purpose of enhancing drivability such as a feeling of acceleration of the vehicle.
The output torque of the engine 1 is controlled by changing VO according to the opening MTVO of the mechanical throttle valve 12.

On the other hand, the exhaust port 16 is connected to the combustion chamber 6
It constitutes an upstream end portion of the exhaust passage 18 for discharging the exhaust gas therein. In FIG. 2, 19 is an injector for injecting and supplying fuel to the intake passage 9 near the intake port 7, and 20 is an ignition plug for igniting intake air in the combustion chamber 6.

The engine 1 is connected to an automatic transmission (not shown). This transmission is equipped with a lock-up clutch having a gear range of forward four speeds, and a shift diagram of shift switching and lock-up switching control of each gear is as shown in FIG. 6, for example, vehicle speed V and mechanical throttle valve 12 The opening is set by MTVO. In FIG. 6, the solid line indicates the shift-up line of each gear, and the broken line indicates the shut-down line. The two-dot chain line indicates the lock-up ON line, and the one-dot chain line indicates the lock-up OFF line.

The mechanical and electric throttle valves 12, 15
Each of the actuators 13 and 14, the injector 19, and the spark plug 20 are configured to be operation-controlled by a control unit 31, and the control unit 31 has a constant speed for controlling the vehicle to run at a constant speed. A traveling control unit 32 (constant speed traveling control means) is included. The control unit 31 includes an output signal of the air flow meter and an opening degree of the mechanical throttle valve 12
The output signal of the mechanical throttle sensor 33 as the throttle opening detection means for detecting MTVO and the electric throttle valve 1
The output signal of the electric throttle sensor 34 that detects the opening ETVO of the vehicle speed 5, the output signal of the vehicle speed sensor 35 that detects the vehicle speed V, the signal of the auto cruise set switch 36 that sets the target vehicle speed, and the setting of the same vehicle speed. Various signals including at least a signal from the cancel switch 37 to release, a signal from the resume switch 38 to restore the canceled set of the same vehicle speed, and a signal from the brake switch 39 that is turned on by depressing the brake pedal 21 (others) , For example, output signals of a water temperature sensor that detects the cooling water temperature of the engine 1 and a rotation speed sensor that detects the engine rotation speed based on the rotation angle of the crankshaft of the engine 1)
Has been entered.

Here, the relationship between the mechanical throttle valve 12 and the electric throttle valve 15 during normal control will be described with reference to FIGS.
This is illustrated by FIG. For example, as shown in FIG. 7, the mechanical throttle valve 12 with respect to the operation amount of the accelerator pedal 10
The opening characteristic of the electric throttle valve 15 is mechanically set in advance, but the opening characteristic of the electric throttle valve 15 is different from the mechanical throttle valve 12, and the opening is larger than the mechanical throttle valve 12 when the accelerator operation amount is small. The map is set so that the opening degree becomes smaller than that of the mechanical throttle valve 12 when the accelerator operation amount increases.

Further, as shown in FIG. 8, during acceleration of the engine 1 where the throttle opening increases, the pulse signal for the injector 19 is different from the normal pulse signal Pa having a pulse width corresponding to the basic fuel injection amount. Of the asynchronous pulse signal Pb, and the asynchronous pulse signal Pb
The fuel increase amount during acceleration is corrected by the number of injections by.

Further, the throttle sensors 33, 34 are
Compare the throttle opening MTVO and ETVO detected by
Based on the smaller one of them, as shown in FIG. 9, the throttle opening change rate is calculated and the number of asynchronous injections is set accordingly. Then, as shown in FIG. 8, during the acceleration of the engine 1, when the opening MTVO of the mechanical throttle valve 12 is changed from the smaller opening MTVO to the smaller opening ETVO of the electric throttle valve 15, the transition is made. The fuel increase value is changed by recalculating the number of asynchronous injections before and after. In that case, before the transition, the mechanical throttle valve 12 has already been
Since the asynchronous injection is started at a setting according to the change rate of the opening MTVO of the fuel cell, and the change in the opening METVO of the electric throttle valve 15 after the transition is gradual, the number of asynchronous injections (fuel increase value) is corrected to be small. I have decided.

Further, in the control unit 31, the mechanical and electric throttle valve 1 at the time of constant speed traveling control is used.
A control procedure for the actuators 2 and 15 will be described with reference to FIG. First, in a first step S1 after the start, it is determined whether or not the change amount of the opening MTVO of the mechanical throttle valve 12 detected by the mechanical throttle sensor 33 is equal to or larger than a predetermined value ΔTVO. This is because the shift position of the automatic transmission is set by the vehicle speed V and the opening MTVO of the mechanical throttle valve 12 (see FIG. 6). Since there is a high possibility that the machine shift will be changed, the condition is judged. When this determination is NO, the step S1 is repeated. When the determination is YES, the process proceeds to step S2 and the resume switch 38
Determines whether is being operated. This judgment is YE
At S, even if the constant speed traveling control is released by depressing the brake pedal 21 or the like during the constant speed traveling control, the resume switch 38 is turned on to automatically return to the constant speed traveling control state to obtain the target vehicle speed. Since it is under the condition that the mechanical throttle valve 12 is opened even if the accelerator pedal 10 is not depressed, the process returns to step S1. On the other hand, when the determination in step S2 is NO, it is confirmed that the opening MTVO of the mechanical throttle valve 12 is not increased by the operation of the resume switch 38, so the process proceeds to step S3. In this step S3, the opening MTVO of the mechanical throttle valve 12 is set.
The gradient of the vehicle traveling path is calculated based on the change amount of In addition, for example, used in Active Sunpension system,
It is also possible to provide a gradient sensor that detects the gradient of the vehicle body and calculate the gradient of the road on the basis of the detection value of the gradient sensor.

Thereafter, in step S4, the target throttle opening zETVO corresponding to the gradient of the electric throttle valve 15 is calculated from the gradient calculated above and the vehicle speed V based on a preset map. As shown in FIG. 4, the map is set so that the target throttle opening zETVO increases as the vehicle speed V increases and the gradient increases, and the throttle opening zETVO corresponding to the vehicle speed V and the gradient is set.
Ask for. For example, in the illustrated example, the vehicle speed V is V = 100 Km / h
When the gradient is 9% and the target throttle opening zETVO is 60
%become.

In the next step S5, the current throttle opening yMTVO and yETVO of the mechanical throttle valve 12 and the electric throttle valve 15 are obtained by the throttle sensors 33 and 34, respectively, and in step S6 the target throttle opening degree of the electric throttle valve 15 is calculated. The current opening yETVO is subtracted from zETVO and the difference zETVO-yETVO is divided into 2%, and the throttle opening ETVO is incremented by 2% toward the target throttle opening zETVO. Furthermore, in the next step S7,
From the set throttle opening xMTVO before changing to the current opening yM before the mechanical throttle valve 12 changes due to the gradient change of the traveling path.
TVO is subtracted and the difference xMTVO-yMTVO is divided every 2%, and the throttle opening MTVO is decremented by 2% toward the set throttle opening xMTVO. After that,
finish.

In this embodiment, step S in the above flow is performed.
1 and S6, the electric throttle valve 15 is operated during the constant speed traveling control of the vehicle in which the constant speed traveling control unit 32 is in the operating state.
The throttle opening degree correction means 40 is configured to correct the opening degree ETVO of the constant speed traveling control section 32 in the opening direction more than when the constant speed travel control section 32 is not operated. The throttle opening degree correction means 40 is detected by the mechanical throttle sensor 33. Mechanical throttle valve 1
When the opening degree MTVO of 2 changes by a predetermined value ΔTVO or more in the opening direction, the opening degree of the electric throttle valve 15 is changed according to the change amount.
ETVO is corrected toward the target throttle opening zETVO in the opening direction.

Therefore, in the above embodiment, the vehicle approaches the uphill road during the constant speed traveling control, and the vehicle shown in FIG.
As shown in, when the opening MTVO of the mechanical throttle valve 12 detected by the mechanical throttle sensor 33 changes in the opening direction, the slope of the uphill road is calculated according to the change amount of the throttle opening MTVO. , This gradient and vehicle speed V
The target opening zETVO of the electric throttle valve 15 is obtained by the, and as shown in FIG. 5B, the opening ETVO of the electric throttle valve 15 is changed from the current opening yETVO to the target throttle opening zE.
The difference between the two openings zETVO and yETVO in the opening direction towards TVO zETV
It is corrected by increasing 2% of O-yETVO. At the same time, as shown in FIG. 5 (a), the increased opening MTVO of the mechanical throttle valve 12 is opened from the current opening yMTVO toward the set throttle opening xMTVO before it changes on the uphill road in the closing direction. The difference between xMTVO and yMTVO is gradually reduced by 2% of xMTVO-yMTVO.

As described above, during the constant speed running control of the vehicle, the opening ETVO of the electric throttle valve 15 is corrected in the opening direction more than when the constant speed running control is not controlled. The action is suppressed, the restriction of intake air by the throttle valve 15 is removed, and the intake amount is not affected by the electric throttle valve 15 and the mechanical throttle valve 1
It is set by the opening MTVO of 2. As a result, the vehicle speed V can be maintained at a constant value without significantly increasing the opening MTVO of the mechanical throttle valve 12 even on an uphill road.
It is possible to suppress unnecessary gear shifting of the transmission due to an increase in the opening MTVO of the.

Further, the opening ET of the electric throttle valve 15
The opening of mechanical throttle valve 12 is used to correct the opening direction of VO.
This is performed when the MTVO changes by a predetermined value ΔTVO or more in the opening direction, and is not performed under other conditions. Therefore, under such conditions, the electric throttle valve 15 can be operated and controlled as usual. The output torque of the engine 1 can be controlled by

In the above embodiment, the mechanical throttle valve 1
2 to the upstream side of the intake passage 9 and the electric throttle valve 15
Are arranged on the downstream side, but the positions of these throttle valves 12 and 15 can be reversed.

[0028]

As described above, according to the first aspect of the invention, the first throttle valve that opens and closes in the intake passage of the engine in conjunction with the accelerator pedal and the second throttle valve that opens and closes when driven by the actuator. A throttle valve is arranged in series and the opening of the second throttle valve is changed according to the opening of the first throttle valve to control the output torque of the engine. When the opening of the first throttle valve is controlled so that the vehicle travels at a constant speed, the opening of the second throttle valve is set to the constant speed running control means when the constant speed running control means is in an operating state. Since the opening direction of the second throttle valve is corrected as compared to when the engine is not operating, the opening amount of the second throttle valve corrects the intake air amount to the engine without being affected by the second throttle valve. It can be set by the opening degree of the rottle valve, and the vehicle speed can be maintained at a constant value without causing a large increase in the opening degree of the first throttle valve even on an uphill road, and unnecessary gear shifting of the transmission can be suppressed. It is possible to prevent discomfort caused by a shift shock during traveling control.

According to the second aspect of the present invention, the opening of the first throttle valve is detected, and when the opening of the throttle changes by a predetermined value or more in the opening direction, the second throttle is adjusted according to the amount of change. Since the opening of the valve is corrected in the opening direction, the output torque of the engine is controlled by the second throttle valve under the condition that the opening of the first throttle valve does not change by a predetermined value or more in the opening direction. You can

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of the present invention.

FIG. 2 is an explanatory diagram showing an overall configuration of a first embodiment of the present invention.

FIG. 3 is a flowchart showing a control algorithm for a throttle valve, which is performed by a control unit.

FIG. 4 is a characteristic diagram of a map for setting a target opening degree of an electric throttle valve.

FIG. 5 is a time chart showing a change in throttle opening during constant speed traveling control.

FIG. 6 is a shift diagram showing shift characteristics of the automatic transmission.

FIG. 7 is a diagram showing a relationship between an accelerator pedal operation amount and a throttle opening.

FIG. 8 is an explanatory diagram showing changes in throttle opening and injection pulses during engine acceleration.

FIG. 9 is a diagram showing a relationship between a throttle opening change rate and the number of asynchronous injections.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 engine 9 intake passage 10 accelerator pedal 12 mechanical throttle valve 14 actuator 15 electric throttle valve 31 control unit 32 constant speed traveling control unit (constant speed traveling control means) 33 mechanical throttle sensor (throttle opening detection means) 40 throttle opening correction means

Claims (2)

[Claims] 1. A first throttle valve that opens and closes in conjunction with an accelerator pedal and a second throttle valve that opens and closes driven by an actuator are arranged in series in the intake passage, and the second throttle valve is provided. In an engine in which the output torque is controlled by changing the opening degree of the first throttle valve according to the opening degree of the first throttle valve, a vehicle equipped with the engine travels at a constant speed.
When the constant speed traveling control means for controlling the opening of the first throttle valve and the constant speed traveling control means are in the operating state, the second speed
And a throttle opening correction means for correcting the opening degree of the throttle valve in the opening direction as compared with the constant speed running control means when it is not operated. 2. The engine control device according to claim 1, further comprising a throttle opening detection means for detecting an opening of the first throttle valve, wherein the throttle opening correction means comprises the throttle opening detection means. When the detected opening of the first throttle valve changes in the opening direction by a predetermined value or more, the opening of the second throttle valve is corrected in the opening direction according to the amount of change. A control device for an engine.