JPH03490B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a throttle valve control device for an engine.

[Prior art]

Recently, with the remarkable development of electronics in vehicle engines, various proposals have been made to electrically control various types of engine control. There is an engine throttle valve control device. In other words, this system electrically controls the throttle valve based on the amount of accelerator operation, and when the rate of change in the amount of accelerator operation exceeds a predetermined value, the target opening of the throttle valve is corrected to a large value, thereby preventing sudden acceleration. This is to improve the responsiveness of the engine. In this type of throttle valve control device,
In general, the accelerator pedal and the throttle valve are connected by a link mechanism or a wire mechanism to mechanically open and close the throttle valve. This has the advantage that the throttle valve can be freely controlled and the pressing force of the accelerator pedal can be reduced.

However, in the throttle valve control device described in the above-mentioned conventional publication, the rate of change in the accelerator operation amount is controlled even when the vehicle starts or when the vehicle is running at low speed due to the correction control of the throttle valve opening based on the rate of change in the accelerator operation amount. When the value exceeds the set value, the throttle valve is opened to a large opening degree, and torque fluctuation increases, which may impair smooth starting performance and low-speed running performance.

[Purpose of the invention]

SUMMARY OF THE INVENTION In view of the above, it is an object of the present invention to provide an engine throttle valve control device that can eliminate the risk of torque shock during starting and low speed running.

[Structure of the invention]

Therefore, the present invention provides an engine in which the throttle valve is electrically controlled based on the amount of accelerator operation, and the target opening of the throttle valve is corrected to a large value when the rate of change of the amount of accelerator operation is greater than a predetermined value. In a throttle valve control device, when the accelerator operation amount is less than a set value, it is determined that it is time to start or when driving at low speed, and the correction of the target opening degree is limited, and the throttle valve is opened when the rate of change of the accelerator operation amount is the minimum. The target opening degree is also determined based on the degree characteristics.

That is, in the present invention, as shown in the functional block diagram of FIG. The throttle valve drive means 42 receives the output of the calculation means 41 and drives the throttle valve 43, while the characteristic correction means 44 receives the output of the accelerator detection means 40 and sets the rate of change of the accelerator operation amount. When the amount of accelerator operation is less than or equal to a predetermined value, the target opening degree is corrected to a large value, and at this time, the characteristic correction limiting means 45 receives the output of the accelerator detecting means 40 and limits the correction by the characteristic correcting means 44 when the accelerator operation amount is less than a predetermined value. The target opening degree is determined based on the throttle valve opening characteristic when the rate of change of the accelerator operation amount is the minimum.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

2 to 6 show an engine throttle valve control device according to an embodiment of the present invention. 2 and 3, 1 is an engine, and a throttle valve 3 is disposed in the middle of an intake passage 2 of the engine 1, and a throttle such as a step motor or a DC motor opens and closes the throttle valve 3. An actuator 4 is attached. This intake passage 2
A vane type air flow meter 5 is provided on the upstream side of the throttle, and the upstream end of the intake passage 2 reaches an air cleaner 6.

Further, a fuel injection valve 7 is provided on the downstream end side of the intake passage 2, and the fuel injection valve 7 is connected to a fuel tank 9 via a fuel supply passage 8.
A fuel pump 10 and a fuel filter 11 are installed in the middle of the
A fuel return passage 12 is connected between the downstream side of the fuel filter 11 and the fuel tank 9, and a fuel pressure regulator 13 is connected in the middle of the passage 12.
is provided so that a constant fuel pressure is supplied to the fuel injection valve 7.

On the other hand, a catalyst 15 for purifying exhaust gas is disposed in the exhaust passage 14 of the engine 1, and an EGR device 16 is disposed between the exhaust passage 14 and the intake passage 2. In this EGR device 16, one end of the EGR passage 17 is connected to the exhaust passage 14.
The other end of 7 is connected to the intake passage 2, and an EGR valve 18 is interposed in the middle of the EGR passage 17.
The valve 18 is provided with a solenoid 19 for driving it.

In Fig. 2, 20 is an accelerator pedal, 21 is a battery, 22 is an igniter, 23 is a distributor, 24 is an accelerator position sensor that detects the amount of operation of the accelerator pedal 20, and 25 is a sensor that detects the engine cooling water temperature. 26 is an intake air temperature sensor that detects the temperature of intake air; 27 is a throttle position sensor that detects the opening of the throttle valve 3; 28 is an O ₂ sensor that detects the oxygen concentration in exhaust gas; 29 is a computer unit that controls the throttle valve opening, fuel injection amount, EGR amount, and ignition timing.

FIG. 4 is a diagram for explaining the arithmetic processing of the throttle valve opening control by the computer unit 29, and for convenience of explanation, the arithmetic processing of the computer unit 29 is shown using a hardware circuit. In the figure, the same reference numerals as in FIGS. 2 and 3 indicate the same parts as in the same figure, 30 is an accelerator differential module that calculates the rate of change dα/dt of the accelerator operation amount α, and 31 is a change in the accelerator operation amount α a deceleration determination module for determining whether or not deceleration is occurring from 32;
Reference numeral 33 and 34 indicate an accelerator opening determination module for determining whether the accelerator operation amount α is equal to or less than a set value K, and 33 and 34 indicate switch means.

Further, 35 is a function generating means that outputs an output value determined by the input x value and y value.
This is actually a given two-dimensional memory map x
The output value is obtained by inputting the value and y value into the address and reading the stored value from the map. Specifically, the basic value is determined according to the accelerator operation amount α and its rate of change dα/dt. Target throttle opening θ
This is a basic target throttle opening generating means that generates. Here, this basic target throttle opening generating means 35 has a plurality of speeds of change of each accelerator operation amount.
Each dα/dt has a map of accelerator operation amount and throttle valve opening characteristics (see MAP1 to MAP8 in Figure 5a), and the characteristics of each map are as shown by characteristic curves a to h in Figure 5b. Furthermore, the basic target throttle opening degree θ for the same accelerator operation amount α is set to be larger as the rate of change dα/dt of the accelerator operation amount becomes larger.

In addition, in the above configuration, the throttle actuator 4 and the computer unit 2
Reference numeral 9 is the throttle valve driving means 42 shown in FIG. 1, and the computer unit 29 realizes the functions of the calculating means 41, characteristic correction means 44, and characteristic correction limiting means 45 shown in FIG. ing.

Next, the operation will be explained using FIGS. 4 to 6.

When the accelerator pedal is depressed, an accelerator operation amount α is detected by the accelerator position sensor 24, and the accelerator operation amount α is input to the computer unit 29. In this computer unit 29, an accelerator differentiation module 30 differentiates the accelerator operation amount α to calculate the rate of change dα/dt of the accelerator operation amount, and a deceleration determination module 31 determines whether or not it is deceleration based on the change in the accelerator operation amount α. Then, the accelerator opening determination module 32 determines whether the accelerator operation amount α is equal to or less than a set value K.

Then, when the vehicle starts or runs at low speed, that is, when the engine is in an accelerating state or a steady state and the accelerator operation amount α is less than the set value K, the switch means 34 receives a judgment signal from the accelerator opening judgment module 32. OFF, the basic target throttle opening generating means 35 selects the accelerator operation amount/throttle valve opening characteristic h corresponding to the minimum change rate dα/dt of the accelerator operation amount (see part A in FIG. 6), and Based on h, a basic target throttle opening θ corresponding to the accelerator operation amount α is generated and outputted to the throttle actuator 4, and the throttle valve 3 receives the accelerator operation amount α and the minimum change rate dα of the accelerator operation amount. The opening is controlled to be determined by the accelerator operation amount and the throttle valve opening characteristic h corresponding to /dt, thereby ensuring smooth starting performance or low-speed running performance.

When the accelerator operation amount α exceeds the set value K in such a state, the switch means 34 is turned on, and the basic target throttle opening generating means 35 performs appropriate accelerator operation according to the rate of change dα/dt of the accelerator operation amount. Based on the accelerator operation amount/throttle valve opening characteristics a to h (see part B in Fig. 6), the basic target throttle opening is determined according to the accelerator operation amount α. degree θ
is generated and this is the throttle actuator 4.
This time, the throttle valve 3 is controlled to an opening determined by the accelerator operation amount α and the accelerator operation amount/throttle valve opening characteristics a to h corresponding to its rate of change dα/dt. Appropriate engine response during acceleration is ensured.

Further, during deceleration, the switch means 34 is turned off in response to a determination signal from the deceleration determination module 31, and therefore, in this case, the same operation as in the case of starting and running at low speed is performed.

In addition, the computer unit 20 calculates and creates a fuel injection pulse with a pulse width corresponding to the operating state of the engine and applies this to the fuel injection valve 7 to control the fuel injection amount, and also controls the igniter 22 according to the rotation of the engine. A signal is applied to control the ignition timing, and a control signal is applied to the solenoid 19 of the EGR valve 18 according to the operating state of the engine.
Although EGR amount control is performed, its operation is the same as that conventionally known, so detailed explanation thereof will be omitted.

In the device of this embodiment as described above, when the accelerator operation amount is less than the set value, the basic target throttle opening is set based on the characteristic corresponding to the minimum change rate of the accelerator operation amount, regardless of the magnitude of the change speed of the accelerator operation amount. In other words, the correction of the throttle valve target opening according to the rate of change of the accelerator operation amount is stopped, so a large torque shock does not occur when starting or when driving at low speed, resulting in smooth starting performance. Alternatively, low speed running performance is ensured.

In addition, with this device, when the accelerator operation amount exceeds the set value, the throttle valve target opening degree is corrected according to the rate of change in the accelerator operation amount, so engine response during normal acceleration can be ensured. At this time, since the correction amount of the throttle valve target opening degree is changed depending on the speed of change of the accelerator operation amount, extremely excellent acceleration response and acceleration performance can be obtained.

Further, FIGS. 7 and 8 show other embodiments of the present invention. In Fig. 7, the same reference numerals as in Fig. 4 indicate the same parts as in Fig. 4, and 36 indicates whether the accelerator operation amount α is less than or equal to the set value K, depending on the accelerator operation amount α and its rate of change dα/dt. This is basic target throttle opening generating means for generating the basic target throttle opening θ. Here, this basic target throttle opening generating means 36 includes the accelerator operation amount α and the rate of change thereof.
There are two types of basic target throttle opening maps with dα/dt as a parameter, corresponding to the accelerator operation amount α above the set value K and below the set value K (No. 8
(see Figures a and b), the amount of accelerator operation for both maps,
The throttle valve opening characteristics are shown in Figure 8 a and b.
As shown by a ₁ to g ₁ and a ₂ to g ₂ , the basic target throttle opening θ for the same accelerator operation amount α becomes larger as the rate of change dα/dt of the accelerator operation amount increases. Also, regarding the map of the basic target throttle valve opening corresponding to the accelerator operation amount α greater than the set value K, each characteristic curve a ₁ to g ₁ is used.
are set at approximately equal intervals from each other, and for the map of the basic target throttle opening corresponding to the accelerator operation amount α below the set value K, each characteristic curve a ₂ to g ₂ shows that the rate of change dα/dt of the accelerator operation amount is The distance between them is set to increase as the distance increases, and therefore, at the same rate of change in the accelerator operation amount, the throttle opening for the same accelerator operation amount will be greater than the set value when the accelerator operation amount is less than the set value. It is smaller than when the accelerator operation amount was .

Next, the operation will be explained.

In this device, when the vehicle starts or runs at low speed, the basic target throttle opening generating means 36
In response to the determination signal from the accelerator opening determination module 32, a map of the basic target throttle opening corresponding to the accelerator operation amount α that is less than or equal to the set value K is selected (see FIG. 8b), and the accelerator is adjusted based on this map. Appropriate accelerator operation amount/throttle valve opening characteristics a ₂ to g ₂ are selected according to the rate of change dα/dt of the accelerator operation amount, which is the output from the differential module 30, and based on these characteristics a ₂ to _{g 2} Accelerator operation amount α
A basic target throttle opening θ is generated according to
This is output to the throttle actuator 4, and the throttle valve 3 adjusts the accelerator operation amount α based on the map corresponding to the accelerator operation amount α below the set value K.
The opening is controlled to be determined by the accelerator operation amount and throttle valve opening characteristics a ₂ to g ₂ corresponding to the rate of change dα/dt.

On the other hand, when the accelerator operation amount α exceeds the set value K, the basic target throttle opening generation means 36 generates a map (see FIG. 8a) of the basic target throttle opening corresponding to the accelerator operation amount α that exceeds the set value K. selected, and based on the map, the accelerator operation amount α
A basic target throttle opening θ determined by the accelerator operation amount and throttle valve opening characteristics a ₁ to g ₁ corresponding to the rate of change dα/dt is generated, and the throttle valve 3 is operated according to this basic target throttle opening. It will be controlled by θ.

In the device of this embodiment as described above, when the accelerator operation amount is less than the set value, the correction is limited and the target opening is determined based on the throttle valve opening characteristic when the rate of change of the accelerator operation amount is the minimum. As a result, a large torque shock does not occur when starting or running at low speed, and smooth starting performance and low-speed running are ensured.

Note that in the above embodiment, when the accelerator operation amount is less than the set value, the correction of the throttle valve target opening is stopped or the correction amount is reduced, but in the present invention, for example, the throttle valve target opening is adjusted with a delay. The correction may be started, or in any case, the correction may be temporarily stopped or otherwise limited.

〔Effect of the invention〕

As described above, according to the present invention, the throttle valve is electrically controlled based on the accelerator operation amount, and the target opening degree of the throttle valve is corrected to a large value when the rate of change of the accelerator operation amount is equal to or higher than a predetermined value. In this engine throttle valve control device, when the accelerator operation amount is less than a set value, it is determined that it is time to start or when running at a low speed, and the correction of the target opening degree is limited, so that the rate of change in the accelerator operation amount is minimized. Since the target opening is determined based on the throttle valve opening characteristic at the time of the vehicle, the possibility of torque shock during starting and low speed running can be eliminated.

[Brief explanation of the drawing]

FIG. 1 is a functional block diagram showing the configuration of the present invention.
FIG. 2 is a schematic configuration diagram of an engine throttle valve control device according to an embodiment of the present invention, FIG. 3 is a configuration diagram of the main parts of the device, and FIG. 4 explains the arithmetic processing of the computer unit 29 in the device. Figures 5a and 5b are diagrams for explaining the map of the basic target throttle opening of the computer unit 29 and the characteristics of the basic target throttle opening with respect to the amount of accelerator operation and its rate of change, respectively. 7 is a diagram showing the characteristics of the basic target throttle opening degree with respect to the accelerator operation amount and its rate of change to explain the operation of the above device, and FIG. 7 explains the calculation process of the computer unit 29 in another embodiment of the present invention. Figures 8a and 8b are for explaining the characteristics of the basic target throttle opening relative to the accelerator operation amount of the computer unit 29 and its rate of change when the accelerator operation amount is above the set value and below the set value, respectively. This is a diagram. 40... Accelerator detection means, 41... Calculation means, 42... Throttle valve driving means, 43... Throttle valve, 44... Characteristic correction means, 45... Characteristic correction limiting means, 3... Throttle valve, 4... ...Throttle actuator, 24...Throttle position sensor, 29...Computer unit.

Claims (1)

[Claims] 1. Accelerator detection means for detecting the amount of accelerator operation; calculation means for receiving the output of the access detection means and calculating the target opening degree of the throttle valve; and throttle valve driving means for receiving the output of the calculation means and driving the throttle valve. , characteristic correction means that receives the output of the accelerator detection means and corrects the target opening degree to a larger value when the rate of change of the accelerator operation amount is equal to or higher than a set value; The characteristic correction limiting means is provided to limit the correction by the characteristic correction means and determine the target opening based on the throttle valve opening characteristic when the rate of change of the accelerator operation amount is the minimum in the following cases. The engine throttle valve control device.