JP2730393B2 - Fuel supply system for gasoline internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel supply device for a gasoline internal combustion engine.

[0002]

2. Description of the Related Art FIG. 2 is an explanatory view showing the structure of a conventional fuel supply system. In FIG. 2, reference numeral 1 denotes a throttle valve for controlling the amount of air supplied to an internal combustion engine, and reference numeral 2 denotes an upstream of the throttle valve to supply required fuel. Injecting fuel injection valves 3a are heaters that heat fuel floating downstream from the upstream of the throttle valve to promote vaporization.

Next, the operation of this conventional fuel supply device will be described. Fuel corresponding to the operation state of the internal combustion engine determined by opening and closing of the throttle valve 1 is injected from the fuel injection valve 2. Next, the injected fuel is about to be sucked into the internal combustion engine together with the intake air, but is heated by the heater 3a provided in the middle of the intake passage, so that vaporization is promoted. The vaporized air-fuel mixture is sucked into each cylinder and burned.

[0004]

Since the conventional fuel supply system is constructed as described above, the air pressure loss caused by the heater 3a has been large. Further, when the heater 3a is made smaller in order to reduce the air pressure loss, there is a problem that the effect of the vaporizing action by heating is reduced. In addition, there is a problem that it cannot be adapted to multipoint injection. Further, there is a problem that the vaporization efficiency is deteriorated when the fuel amount applied to the heater 3a is too large, and the heater efficiency is deteriorated when the fuel amount is too small.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems. In order to reduce the air pressure loss caused by the heater as much as possible, to secure the engine output under a high load, to increase the heater efficiency, It is an object of the present invention to provide a fuel supply device for a gasoline internal combustion engine which is capable of coping with injection, and which has an appropriate contact amount of spray to a heater to increase vaporization efficiency and heater efficiency.

[0006]

In the fuel supply system for a gasoline internal combustion engine according to the present invention, a heater for heating fuel and promoting vaporization is provided on a side wall in the middle of each intake passage to reduce intake pressure loss and to increase a multi-cylinder internal combustion engine. A first fuel injection valve that injects fuel toward the intake valve and a second fuel injection valve that injects fuel toward the heater for each cylinder of the first cylinder. In performing injection by both the valve and the second fuel injection valve, a ratio of an injection amount of the first fuel injection valve to an injection amount of the second fuel injection valve is made variable depending on an operation state of the internal combustion engine. And

[0007]

According to the fuel supply system for a gasoline internal combustion engine of the present invention, the heater for heating the fuel injected from the second fuel injection valve provided upstream is provided on the side wall in the middle of each intake passage, so that the air pressure loss is small. Thus, the engine output at the time of high load is secured. In addition, the first fuel injection valve and the second
Since the ratio of the injection amount of the fuel injection valve is made variable depending on the operation state of the internal combustion engine, the fuel injection amount to the heater becomes the optimum fuel amount that can be atomized by the heater, and the heater efficiency is improved.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 4 denotes a first fuel injection valve for injecting fuel toward an intake valve, and reference numeral 5 denotes a portion of the fuel amount upstream of the first fuel injection valve which corresponds to an operating state of the internal combustion engine. A second fuel injection valve 3b for injecting a fuel amount corresponding to a ratio determined by the operating state of the fuel injection valve 3b is provided on a side wall in the intake passage of each cylinder of the multi-cylinder internal combustion engine and is injected from the second fuel injection valve 5. A heater 6 for heating fuel and promoting vaporization is provided with a first fuel injection valve 4 and a second fuel injection valve 4 in accordance with the operation state of the internal combustion engine.
Is a computer unit that determines the injection amount of the fuel injection valve 5 and outputs a drive signal.

Next, the operation of the fuel supply device for a gasoline internal combustion engine of this embodiment will be described. Of the fuel amount corresponding to the operation state of the internal combustion engine, the second fuel injection valve 5 has a fuel amount of a ratio determined by the operation state of the internal combustion engine, such as the water temperature, the engine speed, and the load, which are stored in the computer unit 6 in advance. Inject. Further, the first fuel injection valve 4 injects the remaining ratio of fuel amount. At this time, the fuel injected from the second fuel injection valve 5 hits the heater 3b provided on the side wall in the middle of the intake passage of each cylinder and is heated to promote vaporization.

As described above, the second fuel injection valve 5 is provided on the upstream side of the first fuel injection valve 4, and the heater 3b for heating the fuel injected from the second fuel injection valve 5 is provided in the middle of each intake passage. , The air pressure loss is reduced, and the engine output under a high load is ensured. Also, the first
The ratio of the fuel injection amount of the fuel injection valve 4 to the fuel injection amount of the second fuel injection valve 5 is made variable depending on the operation state of the internal combustion engine, so that the fuel injection amount to the heater 3b is the optimum fuel that the heater 3b can atomize. And the heater efficiency is improved.

[0011]

As described above, according to the fuel supply system for a gasoline internal combustion engine of the present invention, the air pressure loss caused by the heater is minimized and only the amount of fuel that can be atomized by the heater is injected toward the heater. Therefore, the vaporization efficiency and the heater efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a configuration explanatory view showing a fuel supply device for a gasoline internal combustion engine according to one embodiment of the present invention.

FIG. 2 is a configuration explanatory view showing a conventional fuel supply device.

[Explanation of symbols]

 3b heater 4 first fuel injection valve 5 second fuel injection valve 6 computer unit

──────────────────────────────────────────────────の Continuation of the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical display location F02M 53/02 F02M 69/00 320A 31/12 301T 301G

Claims (1)

(57) [Claims] 1. A first fuel injection valve provided for each cylinder of a multi-cylinder internal combustion engine, and the first fuel injection valve upstream of the first fuel injection valve and independent of each other. A second fuel injection valve whose injection is controlled, a heater located on a side wall in the middle of the intake passage of each cylinder and heating the spray injected from the second fuel injection valve to promote vaporization, and a fuel injection valve. Fuel supply for a gasoline internal combustion engine comprising: a computer unit that outputs a drive signal and varies an injection amount ratio between the first fuel injection valve and the second fuel injection valve in accordance with an operation state of the internal combustion engine. apparatus.