JPH03225047A - Fuel feed control device for internal combustion engine - Google Patents

Abstract

PURPOSE:To keep the vehicle speed time-change rate constant during an acceleration operation and improve operability by controlling the fuel feed quantity to an internal combustion engine to make the vehicle speed time-change rate constant when the vehicle speed time-change rate is not constant during the acceleration operation of the internal combustion engine. CONSTITUTION:Detecting means such as a vehicle speed sensor 14, an engine rotating speed sensor 16 and a throttle sensor 18 are connected to a control means 12 connected to a fuel discharge section 10. The signal from the throttle sensor 18 is inputted to the control means 12 during the acceleration operation of an internal combustion engine 4, the signal from the vehicle speed sensor 14 is inputted to an acceleration arithmetic section 20, if the vehicle speed time-change rate is not constant due to the fuel with a different nature used as the specific fuel, the fuel discharge section 10 is controlled to increase the fuel quantity to the internal combustion engine 4 then that when the normal acceleration augmentation is corrected so that the vehicle speed time-change rate is made constant. The vehicle speed time-change rate can be kept constant, and drivability can be improved.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a fuel supply control device for an internal combustion engine, and in particular, it is capable of keeping the rate of change in vehicle speed constant over time during acceleration operation of the internal combustion engine even when fuels with different properties are used. The present invention relates to a fuel supply control device for an internal combustion engine that can improve drivability by maintaining

[Conventional technology]

The internal combustion engine of a vehicle is provided with a fuel supply control device that controls the amount of fuel supplied depending on the operating state of the internal combustion engine. Some of these fuel supply control devices are equipped with a fuel injection valve that injects fuel into an intake pipe or a combustion chamber, and a fuel discharge section such as a carburetor that properly mixes fuel and air to be supplied to the combustion chamber.

In such a fuel supply control device for an internal combustion engine of a vehicle, the throttle valve is opened by depressing the accelerator pedal.
Some vehicles attempt to improve drivability by increasing the amount of fuel supplied when accelerating the vehicle by accelerating the internal combustion engine, that is, by performing acceleration increase correction to enrich the air-fuel ratio.

Further, as a fuel supply control device, for example, JP-A-1-1
It is disclosed in Japanese Patent Application Laid-open No. 10850 and Japanese Patent Application Laid-Open No. 63-272935. The system described in Japanese Patent Application Laid-Open No. 1-110850 sets the basic fuel supply amount according to the operating range such as engine load and rotation speed, and also increases the amount of fuel according to the operating state such as engine temperature and accelerator change rate. is set, and furthermore, the distillation property of the fuel is detected, and when the distillation property is high, the fuel increase value is increased. Also, JP-A-63-
What is described in the 272935 publication is based on the detected value of a factor that changes depending on the difference in volatility, and whether this factor falls within a predetermined range or not, determines whether the standard fuel has changed to a heavy fuel or a light fuel. If it is determined that there has been a change, the correction ■ for the fuel properties after the change is calculated, and the control amount related to combustion is corrected using this correction amount. This makes it possible to apply the system to other fuels, and avoids situations where exhaust emissions or drivability become poor even if an unexpected fuel is used.

[Problem that the invention seeks to solve]

By the way, in the conventional acceleration increase correction during acceleration, as shown in FIG. Then ([1 in Figure 4 <a>)
and [indicated by 2), the acceleration increase correction, that is, the fuel supply amount is increased (indicated by 31 and a2 in FIG. 4(C)),
This enriches the air-fuel ratio during acceleration and improves engine output.

However, depending on the nature of the fuel used, the amount of increase in fuel amount for acceleration increase correction during acceleration operation varies.

For this reason, if the fuel used is of poor quality, the increase in fuel during acceleration will be insufficient, and if the fuel increase is corrected at a fixed rate, the rate of change in vehicle speed over time (acceleration) will remain constant. Therefore, it is no longer possible to maintain a constant time rate of change (indicated by broken lines bl and b2 in Fig. 4(b)), and the acceleration state of the vehicle becomes low (as indicated by cl and C2 in Fig. 4(b)). ), there was a disadvantage that drivability deteriorated.

Furthermore, among the fuel properties, the distillation temperature characteristic particularly affects the drivability, and when the internal combustion engine is started at a low temperature (immediately after starting), there is an inconvenience such as breathing during acceleration.

[Purpose of the invention]

Therefore, the purpose of this invention is to eliminate the above-mentioned disadvantages.
A control means is provided for supplying a specific fuel to the internal combustion engine and controlling the amount of fuel supplied to the internal combustion engine so as to maintain a constant time rate of change in vehicle speed when the rate of change in vehicle speed over time is not constant due to the specific fuel during acceleration operation of the internal combustion engine. Thereby, it is possible to realize a fuel supply control device for an internal combustion engine that can maintain a constant time change rate of vehicle speed during acceleration operation and improve drivability even when fuels with different properties are used.

[Means for solving problems]

To achieve this object, the present invention provides a fuel supply control device for an internal combustion engine that controls the amount of fuel supplied according to the operating state of the internal combustion engine of a vehicle. The present invention is characterized in that a control means is provided for controlling the amount of fuel supplied to the internal combustion engine so that the time rate of change of the vehicle speed becomes constant when the rate of change of the vehicle speed over time is not constant due to the specific fuel during driving.

[Effect]

According to the configuration of the present invention, the control means controls the amount of fuel supplied to the internal combustion engine during acceleration operation of the internal combustion engine so that the rate of change over time of the vehicle speed is constant using the specific fuel. Therefore, even if fuels with different properties are used, the rate of change in vehicle speed over time is maintained constant during acceleration operation of the internal combustion engine, resulting in improved drivability.

〔Example〕

Embodiments of the present invention will be described in detail and specifically below based on the drawings.

1 to 3 show embodiments of this invention. In the figure, 2 is a fuel supply control device of a vehicle (not shown);
4 is an internal combustion engine, and 6 is a fuel supply means. In order to supply fuel to the internal combustion engine 4, this fuel supply means 6 includes a fuel pump 8, and a fuel discharge section lO which discharges fuel from the fuel pump 8 to the internal combustion engine 2, such as a fuel injection valve or a carburetor.
It consists of.

This fuel discharge section 10 communicates with control means 12 .

This control means 12 includes a vehicle speed sensor 14 that detects vehicle speed.
Detection means such as an engine rotation speed sensor 16 that detects the engine rotation speed and a throttle sensor 18 that detects the throttle opening state of a throttle valve (not shown) are in communication with each other.

The vehicle speed sensor 14 is in communication with the acceleration calculation section 20 of the control means 12.

The control means 12 inputs a signal from the throttle sensor 18 when the internal combustion engine 4 is accelerating, that is, when the throttle valve is substantially fully open, and also inputs a signal from the vehicle speed sensor 14 to the acceleration calculation section 20. When the rate of change over time of the vehicle speed is not constant due to the use of fuel with different properties as the specific fuel, the amount of fuel to the internal combustion engine 2 is controlled by controlling the operation of the fuel discharge part 10 so that the rate of change over time of the vehicle speed is constant. is made to be larger than that during normal acceleration increase correction.

Next, the operation of this embodiment will be explained based on the flowchart in FIG. 2 and the time charts in FIGS. 3(a), (b), and (c).

First, explanation will be given based on the flowchart shown in FIG.

In the control means 12, when the program starts (step 101), it is determined whether or not the internal combustion engine 2 is being accelerated, that is, the internal combustion engine 2 is being accelerated.
Continue the judgment in 2.

If step 102 is YES during acceleration, it is determined whether the time change rate (acceleration) of the vehicle speed is normal (constant) or not.
(Step 103). If the time change rate is normal (constant) and YES at step +03, the process returns to step 102.

On the other hand, if the time rate of change of the vehicle speed is not normal (constant) due to different properties of the fuel (that is, the acceleration is not constant and step 103 is No), the internal combustion engine (step 104).

This increased fuel amount is calculated by the acceleration calculation unit 20.
It is determined according to the state in which the actual time change rate deviates from a constant time change rate.

Then, in step 105, it is determined whether the time rate of change (acceleration) has been improved. If the time rate of change (acceleration) has been improved and the steering knob 105 is YES, the process returns to step 102, while if the time rate of change (acceleration) has not been improved, the process returns to step 104 to accelerate the process. The aim is to improve the time rate of change (acceleration) by increasing the amount of fuel at the time.

Next, a description will be given based on the time chart of FIG.

When the throttle valve opens from the fully closed state (T in Fig. 3(a))
), the engine enters an accelerated state, and the normal acceleration increase correction is performed (as shown by A1 in FIG. 3(c)).

However, because the specific fuel has different fuel properties,
As shown in Fig. 3(b), the actual time change rate (acceleration) of the vehicle speed is not a constant time change rate (acceleration) Bl, but the time change rate (acceleration) of the actual vehicle speed (Fig. 3(b) solid line C
(indicated by i) may be lower than a constant time rate of change (acceleration) Bl. Then, when the throttle valve is almost fully open,
The vehicle speed becomes a predetermined vehicle speed.

Next, at T2 in Fig. 3(a), the speed is decelerated, and Fig. 3(a)
) When accelerating again by opening the throttle valve almost fully to T3, it is known that the nature of the fuel used during the previous acceleration is different, so at T3 in Figure 3 (,l), the acceleration increasing fuel is is made larger than that during normal acceleration increase correction (indicated by A2 in FIG. 3(C)).

As a result, as shown in FIG. 3(b), the vehicle speed can be maintained at a constant time change rate (acceleration) (indicated by B2 in FIG. 3(b)).

Therefore, even if fuels with different properties are used, the time rate of change in vehicle speed (acceleration) can be maintained constant during acceleration operation of the internal combustion engine 4, and drivability can be improved.

Further, even immediately after starting the internal combustion engine at a low temperature, it is possible to prevent the occurrence of breathing problems and improve acceleration performance.

In the above-described embodiment, the time rate of change in vehicle speed was controlled by acceleration increase correction, but it is also possible to control the time rate of change to be constant using other methods.

〔Effect of the invention〕

As is clear from the above detailed description, according to the present invention,
A control means is provided for supplying a specific fuel to the internal combustion engine and controlling the amount of fuel supplied to the internal combustion engine so as to maintain a constant time rate of change in vehicle speed when the rate of change in vehicle speed over time is not constant due to the specific fuel during acceleration operation of the internal combustion engine. As a result, even if fuels with different properties are used, the time rate of change in vehicle speed can be maintained constant during acceleration driving, and drivability can be improved.

In addition, with electronic fuel injection type fuel supply control devices, it is possible to improve drivability using existing components, and the amount of fuel supplied can be adjusted to keep the rate of change in vehicle speed constant over time by simply changing the program of the control means. can be controlled at low cost.

[Brief explanation of drawings]

1 to 3 show embodiments of the present invention, FIG. 1 is a block diagram of a fuel supply control device, FIG. 2 is a flowchart explaining the operation, and FIGS. 3(a), (b), (C ) is a time chart of throttle opening, vehicle speed, and acceleration increase. FIGS. 4(a), (b), and (C) are time charts of the throttle opening, vehicle speed, and acceleration increase in the prior art. In the figure, 2 is a fuel supply control device, 4 is an internal combustion engine, and 6 is a fuel supply control device.
12 is a control means, 14 is a vehicle speed sensor,
18 is a throttle sensor, and 20 is an acceleration calculation section.

Claims (1)

[Claims] 1. In a fuel supply control device for an internal combustion engine that controls a fuel supply amount according to an operating state of the internal combustion engine of a vehicle, a specific fuel is supplied to the internal combustion engine, and a vehicle speed changes over time due to the specific fuel during acceleration operation of the internal combustion engine. 1. A fuel supply control device for an internal combustion engine, comprising a control means for controlling the amount of fuel supplied to the internal combustion engine so that the rate of change over time of the vehicle speed is constant when the rate is not constant.