JPS5838338A - Control system for supplying fuel for internal-combustion engine - Google Patents

Abstract

PURPOSE:To improve a response property by a method wherein the requested amount of fuel for the engine is operated promptly from the output frequency of an air volume sensor and the fuel is supplied continuously to the engine in accordance with the result of the operation. CONSTITUTION:The output frequency of the air volume sensor 1 is measured by the control system 6 and the basic requested amount of the fuel with respect to a suction air volume at that time is operated. Simultaneously, the correction coefficient for the amount of fuel is obtained from respective informations such as a water temperature sensor 8, an air/fuel ratio sensor 10, a suction air temperature sensor 9, a throttle opening degree sensor 7 or the like while a magnified correction for the basic requested amount of fuel is effected based on said correction coefficient. The result of said operation is transmitted to an actuator 3 through an amplifying unit 17 and thereby controlling the flow amount of the fuel discharged from a fuel control vale 2.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improving the responsiveness of a fuel supply system for an internal combustion engine using an electronic fuel control device.

Conventionally, fuel supply systems for internal combustion engines have used a system in which a fuel control valve is opened and closed intermittently in synchronization with the rotation of the engine to supply the required amount of fuel to the engine. is synchronized with the rotation of the engine, so even if the amount of intake air increases during rapid acceleration, fuel will not be supplied to the engine until the next rotation signal arrives. Therefore, fuel cannot be quickly supplied in accordance with the amount of intake air, resulting in a response delay, resulting in an undesirable phenomenon in which the air-fuel ratio of one engine becomes lean, sometimes resulting in a misfire. Also,
Another drawback is that since fuel is supplied intermittently, mixing with intake air and atomization are uneven, which adversely affects combustion in the engine.

In order to eliminate such drawbacks, the present invention uses an air amount sensor with a frequency output with excellent responsiveness, quickly calculates the required fuel amount of the engine from the output frequency of this sensor, and continuously sends the fuel amount to the engine according to the calculation result. It is an object of the present invention to provide a fuel supply device for an internal combustion engine that improves responsiveness by supplying fuel in a consistent manner.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on embodiments shown in the drawings. In FIG. 1, (1) is an air amount sensor that outputs a frequency according to the amount of intake air into the intake pipe.

(2) is a fuel control valve that continuously discharges fuel; (3)
is an actuator for controlling the amount of fuel discharged by raising and lowering the valve (2) of the fuel control valve (2), and (4) is a throttle valve provided in the intake pipe, which controls the flow rate of the mixture of air and fuel. (5) is an internal combustion engine driven by igniting and exploding the air-fuel mixture, (6) is a control device that controls the fuel injection valve (2), and controls the actuator (3). It controls the operation and adjusts the amount of fuel discharged from the fuel injection valve (2) to an optimum value. (7) is a throttle opening sensor that measures the opening of the throttle valve (4); ) is a water temperature sensor that measures the cooling water temperature of the internal combustion engine, (9) is an intake air temperature sensor that measures the temperature of the air taken into the intake pipe, and 00 is an air-fuel ratio provided on the exhaust pipe side of the internal combustion engine. A sensor, α■ is a fuel pressure regulator that adjusts the pressure of fuel supplied to the fuel control valve (2) to a predetermined value, and (to) is a fuel pump that pumps the fuel within the frame to the fuel tank (2). It is being pumped to

QO is a calculation unit of the control device (6) that calculates each information from each sensor, αe is a program unit that instructs calculation procedure and method to calculation unit 05, and Q71 is the calculation unit (to).
This is an amplification section that outputs the signal obtained by the actuator (3) to the actuator (3).

In the above configuration, first, the output obtained from the air amount sensor (11) has a characteristic that the frequency is proportional to the amount of intake air into the engine, as shown in FIG.

Such characteristics, for example, generate Karman vortices.

This can be achieved by detecting the frequency at which this vortex occurs. Such output characteristics can be extracted as a pulse-like signal with respect to the time axis as shown in Figure 8, and the wave number of culm debris with a large amount of intake air becomes high, so the period becomes short. . Here, the output cycle of the °C air amount sensor (1) is TaI
Then, this cycle is measured by the control device (6), the basic required fuel amount for the intake air amount at this time is calculated, and at the same time, the water temperature sensor (8), air-fuel ratio sensor Q, intake temperature sensor (9), A fuel amount correction coefficient is determined from each piece of information such as the throttle opening sensor (7), and this correction coefficient is magnified to the basic required fuel amount. This calculation result is sent to the amplification section (
The fuel flow rate transmitted to the actuator (3) via the fuel control valve (2) and discharged from the fuel control valve (2) is Qa shown in FIG.
It is controlled as follows. This fuel amount calculation is performed for each period of the output pulse of the air amount sensor (1) based on the measurement result of the immediately preceding pulse period, so the fuel supply is delayed by one period of the air amount sensor (1). will be updated.

Furthermore, when the intake air amount increases by increasing the opening degree of the throttle valve (4), the air amount sensor (1) shown in FIG.
) is shortened from Tal to Tb1, but this time width is immediately measured in the control device (6) and the fuel supply amount is updated to Qb.

Therefore, the disadvantage of conventional devices is that the fuel supply is interrupted until a signal synchronized with the rotation of the engine arrives, and furthermore, it is not possible to increase the amount of fuel in response to changes in conditions such as engine acceleration. Embodiment of the Invention Since fuel supply is carried out continuously and the update control of the fuel supply amount is carried out based on a frequency signal corresponding to the intake air quantity, responsiveness is significantly improved. This is because the relationship between changes in the frequency signal obtained from the air amount sensor is based on the opening degree of the throttle valve (4).
≧＼ It follows the sudden change without time delay, but the speed of change of the engine rotation speed is relatively slow due to the delay of the mechanical system.

As described above, according to the present invention, the fuel supply to one engine is controlled continuously rather than intermittently, and the fuel supply amount is determined by at least one period of the air amount sensor that outputs a frequency signal according to the intake air amount. The calculation result is then used to immediately control the amount of fuel supplied to the engine, resulting in a significant improvement in the responsiveness of fuel amount control and an excellent effect of smooth engine operation. have

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the fuel supply system for an internal combustion engine according to the present invention, FIG. 2 is a characteristic diagram of the air amount sensor shown in FIG. 1, and FIG. 8 shows the responsiveness of fuel control. It is an explanatory diagram. In the figure, (1) is the air flow sensor, (2) is the fuel control valve, (3) is the actuator, (6) is the internal combustion engine, (6) is the
is a control device, (7) is a throttle opening sensor, (8) is a water temperature sensor, (9) is an intake temperature sensor, and 01 is an air-fuel ratio sensor. Figure 1 Figure 2 Figure 3 223-

Claims (1)

[Claims] An air amount sensor that generates a frequency signal corresponding to the amount of air taken into the engine; calculating the basic fuel amount required by the engine from at least one cycle of the frequency signal obtained from the air amount sensor; and calculating the basic fuel amount required by the engine. A calculation device that magnifies the fuel amount correction coefficient corresponding to various parameters such as engine temperature, intake air temperature, acceleration/deceleration state, etc., and continuously adjusts the amount of fuel to be supplied to the engine according to the calculation results obtained from the calculation device. A fuel supply control device for an internal combustion engine, comprising a fuel control valve for controlling the fuel supply.