JPS63219850A - Engine control device - Google Patents

Abstract

PURPOSE:To enhance operating performance, by obtaining a car speed correction value in accordance with the change rate of an accelerator control amount to be added to the present car speed at least in the time of steady operation so that it agrees with requirement of the driver when the target car speed is set on the basis of an accelerator control amount. CONSTITUTION:A control unit 25, which inputs detection values from an accelerator sensor 26 detecting a step in amount of an accelerator 5, car speed sensor 27 and a throttle sensor 28, controls the opening of a throttle valve through a throttle actuator 18 so as to obtain a target car speed corresponding to an accelerator step in amount. The control unit 25, when it sets the target car speed corresponding to the accelerator step in amount, calculates a car speed correction coefficient in accordance with a change rate of the accelerator step in amount, multiplying the basic target car speed by the car speed correction coefficient and calculating the target car speed at the time of acceleration.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention calculates a target vehicle speed based on the amount of accelerator operation, and increases engine output by 1% J1H in accordance with the target vehicle speed.
The present invention relates to an engine control device configured to do so.

(Prior Art) Conventionally, as an engine control device, instead of directly controlling the engine output through accelerator operation, a throttle valve or the like is used as a substitute to control the engine output based on a control amount determined in response to the throttle operation amount, etc. A technique for increasing the degree of freedom in output control is known, for example, as seen in Japanese Patent Laid-Open No. 57-65835.

Normally, when controlling engine output such as throttle opening electrically in response to the amount of accelerator operation, there is a method in which the control amount such as throttle opening is set directly in response to the amount of accelerator operation; There are methods that set the required output based on the amount of accelerator operation, and methods that set the target vehicle speed based on the amount of accelerator operation. This method sets the target vehicle speed based on the vehicle speed.

When setting the target vehicle speed with respect to the amount of accelerator operation as described above, conventionally, the amount of accelerator operation and the target vehicle speed are set based on a linear relationship.

(Problem to be Solved by the Invention) However, if the target vehicle speed is set uniquely based on the absolute operation position of the accelerator operation amount, it will not meet the requirements associated with the driver's accelerator operation, and the There is a risk that the vehicle speed and the target vehicle speed may deviate, resulting in dissatisfaction with the operating feel. In other words, when accelerating or decelerating, the driver operates the accelerator at a speed corresponding to the degree of acceleration or deceleration, but setting the target vehicle speed based on this operation is independent of the operation speed, and the final The target vehicle speed will be the same depending on the accelerator position, and the transition speed between them will only be faster.

However, in actual accelerator operation, the fact that the operation speed is high means that the target vehicle speed required by the driver is also high, and if this only corresponds to the amount of accelerator operation, there may be cases where the target vehicle speed is not met. Become.

Therefore, the present invention has been developed in view of the above circumstances.For example, the request for the vehicle speed of the accelerator operation after the transition to steady driving after starting is not the absolute operation amount of the accelerator operation, but rather the relative operation amount, that is, in which direction and how much the accelerator operation is performed. It is an object of the present invention to provide an engine control system that enables more accurate engine output control based on the finding that corresponding settings meet the driver's requirements.

(Means for Solving the Problems) The engine control device of the present invention includes an accelerator operation amount detection means for detecting an accelerator operation amount, and an output of the accelerator operation amount detection means, and a target based on the accelerator operation amount. A target vehicle speed setting means for setting a vehicle speed, and an output control means for controlling an engine output in accordance with the target vehicle speed determined by the target vehicle speed setting means, and a rate of change in the accelerator operation amount from the output of the accelerator operation amount detection means. and correction value setting means for receiving a signal from the change rate calculation means and calculating a vehicle speed correction value according to the rate of change, and the target vehicle speed setting means receives a signal from the correction value setting means. , the target vehicle speed is set by adding a vehicle speed correction value to the current vehicle speed, at least in a steady driving state.

FIG. 1 is an overall configuration diagram showing clearly the configuration of an engine control device according to the present invention.

An output control means 2 is provided for the engine 1 to control the engine output by controlling, for example, the throttle opening or the amount of control lever operation of the fuel injection pump. This output control means 2 has a control for setting the control WJ amount.
It outputs a control signal from the um setting means 3 and controls the engine to a predetermined output state.

Further, the target vehicle speed signal set by the target vehicle speed setting means 4 is outputted to the W control amount setting means 3, and the control amount is set in accordance with the target vehicle speed. The target vehicle speed setting means 4
A signal is outputted from the accelerator operation amount detection means 6 which detects the accelerator operation amount from the operation amount of the accelerator pedal 5, and the target vehicle speed is set based on this accelerator operation amount.

Furthermore, a rate of change calculation means 7 is provided for determining the rate of change in the accelerator operation amount from the output of the accelerator operation amount detection means 6, and receives a signal from the change rate calculation means 7 and calculates a vehicle speed correction value according to the rate of change. A correction value setting means 8 is provided. Further, the signal of this correction value setting means 8 is outputted to the target vehicle speed setting means 4, and the target vehicle speed setting means 4 inputs the correction value setting means 8 to the current vehicle speed such as the current target vehicle speed at least in the steady driving state. The target vehicle speed is set by adding the vehicle speed correction value. The vehicle speed correction value is set to a large value when the rate of change of the accelerator operation amount is large, and the final target vehicle speed is set to a large value to match the vehicle speed requested by the driver.

(Function) In the control t11 device as described above, a target vehicle speed is set in accordance with the accelerator operation amount, and a control amount is set based on this target vehicle speed to control the engine output. Even if the accelerator operation amount is the same, the target vehicle speed is set to a different value depending on the rate of change. Therefore, when the rate of change in the amount of accelerator operation is large, the target vehicle speed correction value is also set to a large value.
This matches the target vehicle speed requested by the driver, and ensures good driving performance by providing engine output control that is more responsive to accelerator operation.

(Example) The present invention will be described in detail below with reference to the drawings.

FIG. 2 is a schematic configuration diagram of a concrete example of an engine control device. In the engine of this example, the engine output is controlled by adjusting the opening degree of the throttle valve.

The engine 1 is provided with an intake passage 15 for supplying intake air and an exhaust passage 16 for discharging exhaust gas, and the intake passage 15 is provided with a throttle valve 17 for adjusting the amount of intake air. The throttle valve 17 is opened and closed by a throttle actuator 18 such as a stepping motor.

Further, the output of the engine 1 is transmitted from a transmission 19 to a propeller shaft 20. Differential gear 21, axle 22
The signal is transmitted to the drive wheels 23 via the .

Control of the engine output through the operation of the throttle actuator 18 is controlled by a control signal (pulse signal) from the control unit 25. This control unit 25 has a control 61 for the throttle valve 17]ff.
In order to set i, the accelerator signal from the accelerator sensor 26 that detects the amount of accelerator operation based on the amount of displacement of the accelerator pedal 5, the vehicle speed signal from the vehicle speed sensor 27 provided in the transmission 19, and the opening degree of the throttle valve 17 are used. Throttle signals from the throttle sensor 28 to be detected are respectively input.

The control unit 25 basically converts the accelerator signal from the accelerator sensor 26 into a target vehicle speed, and controls the throttle opening so that the actual vehicle speed converges to the target vehicle speed. In addition, when starting, a target vehicle speed is set according to the accelerator operation amount and vehicle speed, and during steady state, a vehicle speed correction value is determined according to the rate of change of the accelerator and added to the previous target vehicle speed to set the target vehicle speed. During acceleration, the target vehicle speed is set by determining a correction coefficient corresponding to the rate of change of the accelerator and correcting the target vehicle speed.

The processing of the control unit 25 will be explained based on the flowcharts of FIGS. 3 to 5. FIG. 3 shows the main routine, and after starting, initialization is performed in step S1. This initialization involves setting each I10 port, assigning initial values to each register, and initializing various timers.

Next, in step S2, the accelerator signal is A/D converted and accelerator operation IAC is inputted, and in step S3, the actual vehicle speed vsr is inputted. This actual vehicle speed VS is calculated by an interrupt routine every time a vehicle speed pulse is output from the vehicle speed sensor 27. First, the period is calculated from this vehicle speed pulse, and the moving average processing of this period is performed. This is to calculate the actual vehicle speed Vsr.

Step S4 is a running state determination routine, the details of which are shown in the subroutine of FIG. 4. In this subroutine, step S5 determines whether the actual vehicle speed Vsr is 0 or not. If this determination is YES and the vehicle speed is V SrSO, the mode label F1ode is set to vehicle stop mode 5TOP in step S6. Set. If the determination in step S5 is NO, mode label F is determined in step S7.
It is determined whether the mode is set to vehicle stop mode 5TOP, and if this determination is YES and the speed increases from the stopped state, the mode label l"mo is set in step S8.
Set de to start mode 5TART. Further, if the determination in step S7 is NO, it is determined in step S9 whether the actual vehicle speed Vsr has reached a predetermined value of 40+t/h, and if this determination is NO, the bottle chamber value is 40 kl/h or less. In this case, the setting of the start mode 5TART in step S8 is maintained. On the other hand, the determination in step S9 is YES.
If the actual vehicle speed VS exceeds the predetermined value 40) v/h, the accelerator change rate Δ per unit time is determined in step 810.
ACC is at steady state judgment level Ki (for example 1', 'se
Determine whether or not c> or more, and if this determination is NO,
In step S11, the mode label FImode is set to steady mode CRUSE. If the determination in step S10 is YES, it is determined in step 812 whether or not the accelerator change rate ΔACC per unit time is positive. If this determination is YES and the accelerator operation amount is increasing, it is determined in step 813 whether the accelerator change rate ΔACC is equal to or higher than the acceleration determination level by 2 (for example, 18°/sec);
If this determination is YES, the mode label F node is set to acceleration mode ACC in step 814.

Then, in step 515 of the main routine, it is determined whether the mode label F node is set to the vehicle stop mode 5TOP or the start mode 5TART, and if this determination is YES, the target vehicle speed vSOI at the time of start is set in step S16. Configure settings. This target vehicle speed VS
The ol setting is based on the actual vehicle speed ■S relative to the accelerator operation IAC.
The target vehicle speed V Sol is set to increase as r increases, and the target vehicle speed V Sol of the lever in step 817
Set Sol to the final target vehicle speed VSO.

Further, when the determination in step 815 is No, in step 818 the mode label F node is set to steady mode CR.
Determine whether or not it is set to USE, and this determination is Y.
In the case of ES, in step 819, the steady state target vehicle speed VS
Set O□. The setting of this target vehicle speed VSOz is as follows:
The rate of change ΔACC (differential amount) of the accelerator operation IAC is determined from the difference from the previous memory value AC11, and this rate of change ΔACC
Correspondingly, a vehicle speed correction value ΔVSO is determined based on the characteristics shown in FIG. 6, and this vehicle speed correction value ΔVSO is added to the previous target vehicle speed VSOz to set the steady state target vehicle speed VSO2. Then, in step 820, the memory value AC11 of the accelerator operation amount is updated, and in step 821, this target vehicle speed V soz is set as the final target vehicle speed Vso.

The setting characteristics of the vehicle speed correction value ΔVso with respect to the rate of change ΔAcc are as shown in FIG. 6, when the rate of change ΔACC is near 0 and the throttle operation IAC is constant, the vehicle speed correction value ΔV
so is also a value of 0, and when the throttle valve 17 is operated in the opening direction and the rate of change ΔACC increases in the positive direction, the vehicle speed correction value Δ
VSO also increases in the positive direction, and conversely, when the throttle valve 17 is operated in the closing direction and the rate of change ΔACC increases in the negative direction, the vehicle speed correction value ΔVSO is also set to a value that increases in the negative direction.

Further, when the determination in step 818 is No, a target vehicle speed VSO3 during acceleration is set in step 822. This target vehicle speed VSOs is set by determining a vehicle speed correction coefficient KC corresponding to the accelerator change rate ΔACC (differential amount), and setting the basic target vehicle speed Vso by separately calculating this correction coefficient KC.
The target vehicle speed at the time of acceleration ■S03 is set by multiplying by
Set to O.

After setting the target vehicle speed VSO as described above, step 8
The target throttle opening degree TVo of the throttle valve 17 is set in the target throttle opening degree calculation subroutine No. 24 (details are shown in FIG. 5). Then, in the throttle drive interrupt routine of steps 825 to 828 (started every 1 ns), the actual opening TVr of the throttle valve 17 is feedback-controlled to the target opening TVo.

That is, in step 825, the actual opening degree TVr becomes the target opening degree T.
Determine whether it is equal to Vo, and if N is different.

Sometimes it is determined whether the actual opening degree TVr is larger than the target opening degree TVo (826>), and if it is larger (YES), a drive signal is outputted to reduce the number of steps of the stepping motor of the throttle actuator 18 by one step in step S27. to close the throttle valve 17. On the other hand, when the actual opening degree TVr is smaller than the target opening degree TVo (No), a drive signal is outputted to increase the number of steps of the stepping motor of the throttle actuator 18 by one step, and the throttle valve 17 is closed.

The target throttle opening calculation subroutine of step 824 in the main routine performs feedback control of the vehicle speed so that the target vehicle speed VSO and the actual vehicle speed ■Sr match. As shown in FIG. 5, first, in step 830, the target vehicle speed VSOht and the basic required driving force T Ro
Find b by table interpolation. This basic required driving force TRob is determined corresponding to a steady state on a flat road. Then, in step 831, it is determined whether the target vehicle speed VSO is less than or equal to the actual vehicle speed Vsr. If the determination is YES and the target vehicle speed VSO is smaller, the vehicle speed difference between the target vehicle speed VSO and the actual vehicle speed Vsr is determined in step 832. The basic required driving force TR0b is corrected in step 833. This correction is performed using a proportional control component that is corrected by a proportional element proportional to the vehicle speed difference (constant KPd), and an integral control component that is corrected by an integral element that is weighted temporally by subtracting an integral constant KId. , calculate the corrected required driving force T Roc.

On the other hand, if the determination in step 831 is No, the target vehicle speed Vs
If o is larger, the target vehicle speed V is set in step S34.
Calculate the vehicle speed difference between so and the actual vehicle speed Vsr, and proceed to step 8.
In step 35, the basic required driving force TRob is corrected. This correction consists of a proportional control component that is corrected by a proportional element proportional to the vehicle speed difference (constant KPu) L, and an integral control component that is corrected by an integral element that is added by an integral constant KIll to give weight over time. Then, the corrected required driving force TR0C is calculated. Based on the corrected required driving force TRoc obtained as described above, the final target driving force TRO is set in step 336, and in step 837, the final target driving force TRo of the lever and the actual vehicle speed Vs are set.
The target opening degree TVo of the throttle valve 17 is determined by map interpolation based on the map defined by r.

Through the control described above, a vehicle speed correction value is determined according to the rate of change (differential amount) of the accelerator operation amount during steady driving according to the driving state set by the mode label F1ode, and this is used as the current (previous) target vehicle speed. The actual target vehicle speed is set by adding to . Further, at the time of starting, the target vehicle speed is directly set from the accelerator operation amount to match the requested vehicle speed, rather than controlling based on the rate of change as described above.

Furthermore, when accelerating, the target vehicle speed is set high to ensure acceleration performance.

In the above embodiment, an example of engine output control by adjusting the opening of the throttle valve 17 will be explained, but the present invention is also applicable to a diesel engine in which the engine output is adjusted to $7111 by adjusting the control lever of the fuel injection pump. It is possible.

(Effects of the Invention) According to the present invention as described above, the target vehicle speed is set in accordance with the amount of accelerator operation, and even if the amount of accelerator operation is the same, the target vehicle speed can be set to different values in accordance with the rate of change of the amount of accelerator operation. By setting this, when the rate of change in the amount of accelerator operation is large, the target vehicle speed correction value is also set to a large value to match the target vehicle speed requested by the driver, and the engine responds accurately to the accelerator operation. Good operating performance can be ensured by controlling the output.

[Brief explanation of the drawing]

FIG. 1 is a block diagram for clearly showing the configuration of the engine control device of the present invention, FIG. 2 is a schematic configuration diagram of a specific example, and FIGS. 3 to 5 are block diagrams for explaining the processing of the control unit. The flowchart diagram and FIG. 6 are characteristic diagrams showing the setting characteristics of the correction value of the target vehicle speed. 1... Engine, 2... Output control means, 3... Controlled amount setting means, 4... Target vehicle speed setting means, 5...・Accelerator pedal, 6...
... Accelerator operation amount detection means, 7 ... Change rate calculation means, 8 ... Correction value setting means, 17 ...
... Throttle valve, 18... Throttle actuator unit'), 25-... Control unit, 26... Accelerator sensor, 27...
...Vehicle speed sensor.

Claims (1)

[Claims] (1) Accelerator operation amount detection means for detecting the accelerator operation amount; target vehicle speed setting means for receiving the output of the accelerator operation amount detection means and setting a target vehicle speed based on the accelerator operation amount; and the target vehicle speed setting means. An engine control device comprising: output control means for controlling engine output in accordance with a target vehicle speed; A correction value setting means is provided which receives a signal from the calculation means and calculates a vehicle speed correction value according to the rate of change thereof, and the target vehicle speed setting means receives the signal from the correction value setting means and determines the current vehicle speed at least in a steady driving state. An engine control device characterized in that a target vehicle speed is set by adding a vehicle speed correction value to a vehicle speed correction value.