JPS6157938B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuel injection control device for an electric internal combustion engine.

Conventionally, as a fuel injection method for an internal combustion engine, a method has been adopted in which a solenoid valve is used to intermittently pulse fuel and supply it to the engine. In this system, fuel is intermittently supplied to the engine's intake pipe in synchronization with the rotation of the engine. However, since the intake air is continuously drawn into the intake pipe, there is a drawback that the mixing and atomization of air and fuel are uneven, and the air-fuel ratio is not uniform, which tends to make combustion unstable. Since the fuel injection interval is long at low engine speeds, the fuel control has a disadvantage in that the responsiveness of fuel control to changes in engine conditions is poor.

In order to eliminate the above-mentioned drawbacks, the present invention provides a fuel injection control device for an internal combustion engine that is capable of eliminating uneven mixing of air and fuel and improving responsiveness by injecting fuel continuously with high precision. The purpose is to provide

The present invention will be described below based on embodiments shown in the drawings. FIG. 1 shows an implementation of the fuel injection control device for an internal combustion engine according to the present invention, in which numeral 1 is an air amount sensor installed in the intake passage of the internal combustion engine to measure the amount of intake air, and 2 is the amount of fuel injection. It is a fuel control valve that controls the flow rate and has a valve opening degree (flow area) corresponding to the position of the valve body 2a. 3 is an actuator that controls the valve opening of the fuel control valve 2 by controlling the position of the valve body 2a; 14;
1 is a valve position sensor that detects the position of the valve body 2a, 5 is an internal combustion engine, 6 is a control device consisting of an electrical calculation circuit, 4 is a throttle valve, 7 is a throttle opening sensor that is interlocked with the throttle valve 4, and 8 is an internal combustion engine. 9 is an intake air temperature sensor; 10 is an air-fuel ratio sensor; 11 is a fuel pressure regulator for keeping the pressure of the fuel supplied to the fuel control valve 2 constant; 12 is a fuel booster; A pressure pump, 13 is a fuel tank. In the above configuration, the calculation unit 15 of the control device 6 calculates the required basic fuel amount according to the signal from the air amount sensor 1, and calculates the required basic fuel amount from the intake temperature sensor 9, water temperature sensor 8, throttle opening sensor 7, and air-fuel ratio sensor 10. After performing a correction calculation using the obtained various parameters, the comparison amplifier 17 is operated so that the position control signal corresponding to the calculation result and the actual position of the valve body 2a, that is, the signal from the valve position sensor 14 match or have a predetermined relationship. The actuator 3 is driven and fuel injection is performed continuously.

In this way, the position of the valve body 2a is precisely controlled by feedback-controlling the position of the valve body 2a, so that the amount of fuel injected from the fuel control valve 2 is supplied to the engine with high accuracy.

On the other hand, in transient states such as acceleration and deceleration, the amount of fuel can be immediately increased in accordance with the signal obtained from the throttle opening sensor 7 as shown in Fig. 2, and the following The response is extremely excellent because there is no shortage of fuel until the injection timing. In the above explanation, the air amount sensor may be replaced with another one having an equivalent function, for example, an intake pipe pressure sensor, and the throttle opening sensor 7 may be replaced with, for example, the rate of change of the intake air amount. Effects can be obtained. Further, the fuel control valve 2 may be of a metering type using a slit, for example, other than the needle valve type of the embodiment, as long as the position of the fuel control valve 2 is controlled by an actuator and the injection amount of fuel can be continuously varied.

As described above, in the present invention, after the required fuel is calculated by the electronic calculation circuit, the fuel injection amount is continuously varied according to the calculation result, and the position of the valve body of the fuel injection valve is feedback-backed. Since the position of the valve body is controlled by the engine, an accurate amount of fuel can be supplied to the engine.

Therefore, stable combustion with less unevenness in the air-fuel mixture can be obtained, and excellent effects are achieved in that the response of fuel increase correction is quick even in transient conditions such as acceleration and deceleration. Furthermore, since the amount of fuel is calculated by an electronic circuit, there is a degree of freedom in control, and it is easy to adapt to various types of engines.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing an embodiment of a fuel injection control device for an internal combustion engine according to the present invention, and FIG. 2 is a comparative explanatory diagram of fuel injection amount characteristics with respect to changes in throttle valve opening between the present invention and a conventional example. . In the figure, 1 is an air amount sensor, 2 is a fuel control valve, 3 is an actuator, 4 is a throttle valve, 5 is an internal combustion engine, 6 is a control device, 7 is a throttle opening sensor,
8 is a water temperature sensor, 9 is an intake air temperature sensor, 10 is an air-fuel ratio sensor, 11 is a fuel pressure regulator, 14 is a valve position sensor, 15 is a calculation section, and 17 is a comparison amplifier.

Claims (1)

[Claims] 1. A fuel pressure regulator that maintains the pressure of fuel pressurized and supplied by a pressure pump at a constant value, and fuel that receives the pressure regulated by this fuel pressure regulator and flows in response to changes in the position of the valve body. A fuel control valve whose amount changes continuously, a valve position sensor that detects the position of the valve body, an actuator that controls the position of the valve body, and a load state detection means that detects the intake air amount or intake pipe negative pressure of the engine. , correction parameter detection means for detecting at least one of various engine states such as engine temperature, intake air temperature, atmospheric pressure, acceleration/deceleration state, and air-fuel ratio; means for determining the flow rate, correcting the basic fuel flow rate based on the detection output of the correction parameter detection means, and generating a position control signal for the fuel control valve in response to the corrected calculation result; A fuel injection control device for an internal combustion engine, comprising means for controlling the actuator so that the position control signal and a signal obtained from the valve position sensor have a predetermined relationship.