KR20000041078A - Fuel supply system of direct injection type gasoline engine - Google Patents

Abstract

PURPOSE: A fuel supply system of direct injection type gasoline engine is provided to achieve an enhanced start ability of automobile and reduce hazardous exhaust gas while arranging a heater between a fuel rail and an injector so as to accelerate a vaporization of fuel upon a cold start of the automobile. CONSTITUTION: A fuel supply system of direct injection type gasoline engine having a fuel rail(100) for distributing to each combustion chamber the fuel supplied via a fuel pump, and a fuel supply pipe(120) for supplying the fuel distributed from the fuel fail(100) to each injector, the fuel supply system comprising a heater(130) installed in the fuel supply pipe(120) so as to heat the fuel distributed from the fuel rail(100) using a battery as a power source, a heater controller(140) for sensing a temperature of an engine cooling water and controlling an operation of the heater(130), and an engine controller(170) for controlling the heater controller(140).

Description

Fuel supply system of direct gasoline engine

The present invention relates to a direct gasoline engine, and more particularly, a direct gasoline gasoline engine capable of shortening fuel atomization by installing an ultrasonic generator in a fuel rail, and by installing a heater in the fuel supply pipe. It relates to a fuel supply device for an engine.

In general, a gasoline engine can be divided into a carburetor engine and a gasoline injection engine according to the fuel supply method, and the gasoline is injected and supplied by using a high pressure pump instead of the carburetor as the exhaust purification of the engine or high speed and high power are required.

1 is a vertical cross-sectional view showing a fuel supply device of a conventional gasoline engine. As shown in FIG. 1, a coil 6 is installed around the tube between the fuel rail 2 and the injector 4 to heat the fuel flowing into each combustion chamber. At this time, the electromagnetic coil 8 is to be used as a power source. (Reference United States Patent 5159915)

2 and 3 are longitudinal cross-sectional views showing a fuel supply device and an ultrasonic generator of another conventional gasoline engine.

2 and 3, the injector 10 is mounted on the intake manifold 12 side and the intake port 14 side at the same time, and is injected from the injector 10 mounted on the intake manifold 12 side. The fuel to be atomized is configured to be mixed with air after being atomized by the ultrasonic generator 16.

During cold startup, fuel is continuously sprayed on the intake manifold 12 side, and the atomized fuel is atomized using the ultrasonic generator 16, mixed with air, and sucked into the combustion chamber 18 to facilitate ignition and start-up.

In addition, in the case of abnormal operation, particularly in the case of rapid acceleration, the injector 10 mounted on the intake manifold 12 side is injected into the horn 16a of the ultrasonic generator 16 before the intake air enters. It is configured to improve the responsiveness of the engine by being sucked together with the intake air. (Ref. United States Patent 5119775)

In the fuel supply apparatus of the conventional gasoline engine, since the fuel heater is installed around the fuel pipe, power consumption is high and the initial response of the engine is remarkably decreased due to heat transfer to the atmosphere. In addition, there is a problem in that sufficient heat cannot be supplied during cold start, which requires the most heating of fuel because it is a structure that supplies power to the electromagnetic coil without using battery power.

In the case of a direct gasoline engine, fuel is injected directly into the combustion chamber, but in the case of a conventional gasoline engine, the horn of the ultrasonic generator is exposed to the intake pipe, and the fuel is injected to mix with the air as the fuel is atomized. have. This is an ultrasonic fuel atomization technology applied to an engine for injecting fuel into an intake manifold and an intake port, which is not applicable to a direct type engine.

The present invention has been made in view of the above problems, and an object thereof is to provide a fuel supply device for a direct gasoline engine that can not only completely vaporize fuel to realize complete combustion but also help evaporate fuel during cold start.

1 is a vertical cross-sectional view showing a fuel supply device of a conventional direct gasoline engine.

2 and 3 are vertical cross-sectional views showing the fuel supply device and the ultrasonic generator of the conventional gasoline engine, respectively.

Figure 4 is a block diagram showing a fuel supply device for a direct gasoline engine according to the present invention.

5 is a longitudinal sectional view schematically showing a fuel supply apparatus of a direct gasoline engine according to the present invention;

6 is a flow chart illustrating the operation of the present invention.

** Description of symbols for the main parts of the drawing **

100: fuel rail 110: injector

120: fuel supply pipe 130: heater

140: heater control unit 150: ultrasonic generator

160: ultrasonic generator control unit 170: engine control unit

The present invention is to install the ultrasonic generator in the fuel rail to facilitate the atomization of the fuel, and also to install a heater in the fuel supply pipe can shorten the evaporation time of the starting initial fuel, the present invention to achieve the above object It is composed as follows. In other words, in a direct gasoline engine having a fuel rail for distributing fuel supplied through a fuel pump to each combustion chamber and a fuel supply pipe for supplying fuel dispensed from the fuel rail to each injector, the battery is a power source. A heater installed inside the fuel supply pipe to heat fuel dispensed from a fuel rail; A heater controller configured to control an operation of the heater by sensing a temperature of an engine coolant; An ultrasonic generator inside the fuel rail to atomize the fuel inside the fuel rail; The ultrasonic generator control unit for controlling the operation of the ultrasonic generator and the heater control unit and the engine control unit for controlling the ultrasonic generator control unit.

In the above-described configuration, the heater is preferably configured to be installed in the center of the fuel supply pipe.

Hereinafter, a fuel supply device of a direct gasoline engine according to a preferred embodiment of the present invention will be described in detail.

Figure 4 is a block diagram showing a fuel supply device for a direct gasoline engine according to the present invention, Figure 5 is a longitudinal sectional view schematically showing a fuel supply device for a direct gasoline engine according to the present invention. Looking at the configuration of the present invention Before briefly explaining the direct gasoline engine is a direct gasoline engine because the fuel is injected directly into the cylinder is shorter than the time required to evaporate all of the fuel. Therefore, combustion tends to occur before the fuel is completely vaporized and incomplete combustion tends to occur. To prevent this, it is necessary to shorten the time for the fuel to evaporate, and for this, atomization of the fuel must be premised. In the present invention, an ultrasonic generator is installed in the fuel rail to promote atomization of the fuel, and a heater is installed in the fuel supply pipe to help evaporate the fuel during cold start.

Hereinafter, the components of the present invention will be described with reference to FIGS. 4 and 5. In the fuel supply apparatus of the present invention, a fuel supply apparatus of a direct gasoline engine includes a fuel rail 100 for distributing fuel supplied through an intake port to each combustion chamber, and a fuel dispensed from the fuel rail 100 for each injector. The fuel supply pipe 120 to be supplied to the 110, the heater 130 is installed inside the fuel supply pipe 120 to heat the fuel dispensed from the fuel rail 100 by using a battery as a power source of the engine coolant A heater controller 140 for controlling the operation of the heater 130 by sensing a temperature, an ultrasonic generator 150 inside the fuel rail 100 to atomize the fuel in the fuel rail 100, It is composed of an ultrasonic generator control unit 160 for controlling the operation of the ultrasonic generator 150, and the engine control unit 170 for controlling the heater control unit 140 and the ultrasonic generator control unit 160.

The fuel rail 100 described above is an apparatus for equally distributing a predetermined amount of fuel supplied through the intake port to each combustion chamber, and the fuel supply pipe 120 is installed between the fuel rail 100 and the injector 110. It serves to supply the fuel supplied from the fuel rail 100 to each injector 110. The heater 130, which is a characteristic element of the present invention, is installed inside the fuel supply pipe 120 to preheat the fuel dispensed from the fuel rail 100 using the battery as a power source. That is, the heater itself is the same as the conventional one, but uses a battery as a power source, and its installation position is unique. The heater 130 is preferably positioned at the center of the fuel supply pipe 120. The heater controller 140 is configured to control the operation of the heater 130 by always detecting the temperature of the engine coolant detected by the sensor 142. That is, the heater 130 is operated by using the battery as the power source by sensing the temperature of the engine coolant during cold start. On the contrary, the heater 130 is stopped by stopping the power supply of the battery during warming. The ultrasonic generator 150 is installed inside the fuel rail 100 to atomize the fuel in the fuel rail 100, and vibrates energy to fuel flowing into the fuel rail 100 due to the shaking of the horn 102. It is to be atomized while supplying and spraying. The ultrasonic generator control unit 160 controls the operation of the ultrasonic generator 150, and both the ultrasonic generator control unit 160 and the heater control unit 140 are configured to be automatically controlled by the engine control unit 170.

Looking at the operation of the fuel supply of the direct gasoline engine of the present invention configured as described above are as follows.

6 is a flowchart illustrating the operation of the present invention. As shown in FIG. 6, the ultrasonic generator is operated at the same time as the start-up in step S200, and the fuel introduced into the fuel rail is atomized due to the vibration of the horn. Here, the operation of the ultrasonic generator is controlled by the ultrasonic generator control unit and the ultrasonic generator control unit is again controlled by the engine control unit. After the fuel is atomized to a predetermined state in this state, the process proceeds to the next step S210.

In step S210, the sensor detects the temperature of the engine coolant and transmits the detected value from the engine controller. Then proceed to the next step (S220).

In step S220, it is determined whether the detected value detected by the sensor is greater than a preset value. As a result of the determination, if the detected value is not larger than the preset value, the process proceeds to step S230, and if the detected value is large, the process proceeds to step S240.

In step S230, the heater is operated using the battery as a power source to heat the fuel supplied from the fuel rail, and the fuel is supplied to the injector. Here, the operation of the heater is controlled by the heater controller, and the heater controller is controlled by the engine controller. After the heater is heated for a predetermined time, the process proceeds to step S210 to repeat the process following step S210.

In step S240, the heater is interrupted by cutting off the power of the battery, and the process proceeds to step S210 to repeat the process following step S210.

Although the present invention has been described with reference to the preferred embodiments shown in the drawings, which are merely exemplary, and various modifications and equivalent other embodiments are possible to those skilled in the art.

As described above, the present invention provides a heater between the fuel rail and the injector so that the fuel evaporates quickly during cold start and prevents the fuel from burying the piston or the combustion chamber wall. This improves startability, suppresses the generation of unburned hydrocarbons, and reduces emissions that are harmful to incomplete combustion.

In the present invention, the heater is installed as close to the injector as possible so that the fuel is immediately heated at the beginning of the start-up, thereby reducing the unburned hydrocarbon emissions that occur most at the start-up.

In addition, when an ultrasonic generator is installed in the fuel rail and the fuel is injected into the combustion chamber by the injector, the fuel is atomized. As a result, the fuel evaporation time is greatly shortened, and the air and the fuel are well mixed. Can be obtained.

Claims (3)

A direct gasoline engine comprising a fuel rail for distributing fuel supplied through a fuel pump to each combustion chamber, and a fuel supply pipe for supplying fuel distributed from the fuel rail to each injector, A heater installed inside the fuel supply pipe to heat fuel dispensed from the fuel rail using a battery as a power source; A heater controller configured to control an operation of the heater by sensing a temperature of an engine coolant; And A fuel supply device for a direct gasoline engine, characterized in that it comprises an engine control unit for controlling the heater control unit. According to claim 1, Ultrasonic generator is installed inside the fuel rail to atomize the fuel in the fuel rail and And an ultrasonic generator control unit which is controlled by the engine control unit and controls the operation of the ultrasonic generator. The fuel supply apparatus of claim 1 or 2, wherein the heater is installed at an inner center of the fuel supply pipe.