KR100831316B1 - Lpg gas feeding apparatus of gas fuel vehicles - Google Patents

Abstract

An apparatus for preventing fuel from leaking and reducing exhaust gas in a vehicle employing a liquid phase LPG injection system is provided to prevent non-combustion hydrocarbon from being excessively discharged in the initial stage of ignition. An apparatus for preventing fuel from leaking and reducing exhaust gas in a vehicle employing a liquid phase LPG injection system comprises a fuel pump(11) for pumping the fuel contained in a bombe(10), fuel supply lines(31,32) and fuel retrieve lines(33,34), an injector(40) to inject LPG fuel into the engine(20) in a liquid phase, a first pressure regulator(51), and discharge lines(35,36). The fuel supply lines supply the fuel, which is pumped by the fuel pump, to the engine and the fuel retrieve lines retrieve the fuel, which is excessively supplied to the engine. The injector is connected to one side of the fuel supply and fuel retrieve lines.

Description

LPG gas feeding apparatus of gas fuel vehicles

1 is a schematic diagram of an apparatus for preventing fuel leakage and reducing exhaust gas of an LPG liquid injection vehicle according to the present invention;

2 is a schematic view of a discharge line showing a connection relationship between a fuel supply line, a fuel recovery line, and a fuel adsorbent according to the present invention.

<Description of Symbols for Major Parts of Drawings>

10: Bomb 11: Fuel Pump

20: engine 31,32: fuel supply line

33,34: fuel recovery line 35,36: discharge line

40: injector 51: first pressure regulator

52: second pressure regulator 60: solenoid valve

71: oxygen sensor 72: fuel adsorbent

73: oxidation catalyst 74: heating heater

90: fuel rail

The present invention absorbs and regenerates the fuel supplied through the discharge portion connecting the fuel rail on which the injector is installed and the adsorbent for adsorbing / regenerating the fuel, and simultaneously applies a technique for raising the temperature of the catalyst during cold start, The present invention relates to a device for preventing fuel leakage and reducing exhaust gas of an LPG liquid injection vehicle that can prevent air pollution by effectively suppressing the emission of excessive unburned hydrocarbons and effectively cope with exhaust gas emission standards that will be strictly applied in the future.

LPG Liquid Phase LPG Injection (LPLI) is the latest automotive LPG fuel supply system that has been actively used since 1994 in developed countries (Europe, mainly in the Netherlands). The existing LPG engine is configured to supply LPG fuel stored in Bombe and supplied to the engine by vaporizing it through a mixer and a vaporizer, but such LPG engine is provided to a control unit (ECU). It is difficult to start up in winter due to the difficulty of precise control of injection amount of fuel, and the power performance and fuel consumption level are deteriorated, and the tar problem that occurs during combustion of LPG fuel causes unstable during idle and frequent off during starting. have. In order to solve this problem, the LPLI system has been introduced to directly inject LPG fuel into a high pressure liquid phase through an injector without using a mixer and a vaporizer. The LPLI engine directly injects LPG fuel through the injector, allowing more precise control of the timing and amount of fuel injected, improving the fuel efficiency and power performance of the vehicle, improving winter startability and unnecessary maintenance. There is an effect that can be excluded.

In general, the LPLI system fuel supply device adopts the same method as the gasoline injection method and uses the bottom feed injector used in the gasoline engine. This LPLI engine is the same as the mixer type engine, the fuel supply is cut off from the cylinder at the end of the start. In this case, the remaining fuel is present in the liquid phase in the fuel supply line, and when such residual fuel leaks into the intake pipe, a large amount of harmful air pollutants such as hydrocarbons and carbon monoxide are released upon restart, and the fuel is supplied by an excessive supply of fuel. The instability of the air-fuel ratio control adversely affects fuel economy.

As a solution to prevent this phenomenon, the fuel remaining in the LPG fuel line before the injector is collected and circulated at restart, or the fuel leaked from the intake manifold is absorbed and desorbed from the canister through the vacuum pump and the suction / exhaust line. It is proposed to recycle and use.

However, this conventional recirculation unit focuses only on trapping LPG fuel remaining in the fuel line prior to the injector, so the leaked fuel remaining in the intake pipe emits excessive unburned hydrocarbon (THC) at start-up. Is a problem caused by fuel leaked in the intake pipe, that is, it releases a large amount of harmful air pollutants caused by leakage fuel at high temperature restart and cold start, and reduces fuel efficiency and startability due to excessive supply of fuel at initial start-up. I could not solve it. Recirculation technology using the canister also applies a method of forcing the recirculation of the leaked fuel when the engine is turned off by using an additional vacuum pump, so that the vacuum pump is operated using the battery power after the engine is turned off, and the leaked fuel is adsorbed to the canister. When this is completed, there is a problem that the vacuum pump is turned off by the engine control unit after the set timing has elapsed, and the intake / discharge solenoid valve and the air solenoid valve must be interrupted.

In addition, the injector used in the LPLI system is basically the same as the injector used in the gasoline engine. When the injector designed to operate at an injection pressure of about 3 bar is applied to the LPLI system as it is, the operating pressure is 7 bar. Since it is used internally and externally, it is difficult to block fuel leakage at the injector tip caused by the high temperature of each part of the engine after the start-up.

In order to prevent such fuel leakage, it is ideal to develop an LPLI injector separately, but it is not effective considering the cost. LPG fuel leaking from the current LPLI system rapidly flows from the liquid phase to the gas phase when it leaks from the injector tip. Since it expands and is distributed in the gaseous state inside the intake pipe and the combustion chamber, the gas distributed in the gaseous state at the start-up releases a large amount of unburned hydrocarbons, so that it is not possible to cope with air pollution as well as the tightening exhaust gas regulations in the future. have.

Therefore, the present invention has been made to solve the above problems, the fuel supplied through the discharge line connected to the fuel rail injector is installed in the fuel supply system of the LPLI system and the fuel adsorbent for adsorbing / regenerating the fuel Adsorption and regeneration at the same time, while applying technology to increase the temperature of the catalyst during cold start, to prevent excessive pollution of the unburned hydrocarbons generated during the start-up to prevent air pollution, and to meet the emission standards more strictly applied in the future The present invention provides an apparatus for preventing fuel leakage and reducing exhaust gas of an LPG liquid injection vehicle that can effectively respond.

The object of the present invention as described above, LPG fuel injection prevention and exhaust gas of the LPG liquid injection vehicle comprising a cylinder containing the LPG fuel, the engine supplied with the LPG fuel, and a muffler for discharging the combustion gas generated in the engine An apparatus for abatement, comprising: a fuel pump for pumping fuel contained in the bomb, a fuel supply line connected to supply the fuel pumped by the fuel pump to the engine, and a fuel recovery for recovering excess fuel supplied to the engine An injector for supplying LPG fuel to the liquid phase and a first pressure regulator connected to one side of the fuel supply line and the fuel recovery line, the engine and the muffler connected to one side of the line and the fuel supply line and the fuel recovery line. An oxygen sensor, a fuel adsorbent, an outlet having an oxidation catalyst, and one side of the fuel recovery line and one of the fuel adsorbents. It is achieved by the apparatus for preventing fuel leakage and exhaust gas reduction of the LPG liquid injection vehicle characterized in that it comprises a discharge line connected to the side and provided with a solenoid valve and a second pressure regulator.

Further features and advantages of the present invention will become more apparent from the following detailed description based on the accompanying drawings. Prior to this, the terms or words used in the present specification and claims are defined in the technical spirit of the present invention on the basis of the principle that the inventor can appropriately define the concept of the term in order to explain his invention in the best way. It must be interpreted to mean meanings and concepts.

Hereinafter, with reference to the accompanying drawings showing a preferred embodiment of the present invention will be described in detail, in adding reference numerals to the components of each drawing, the same components are possible even if displayed on different drawings It should be noted that the same reference numerals are used. In describing the present invention, when it is determined that the detailed description of the related known functions or configurations may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

1 is a schematic diagram of a device for preventing fuel leakage and reducing exhaust gas of an LPG liquid injection vehicle according to the present invention, and FIG. 2 is a view illustrating a connection relationship between a fuel supply line, a fuel recovery line, and a fuel adsorbent according to the present invention. A schematic drawing of the discharge line shown.

1 and 2, the present invention provides an LPG liquid injection comprising a cylinder 10 in which LPG fuel is accommodated, an engine 20 supplied with the LPG fuel, and a muffler for discharging combustion gas generated from the engine. In the apparatus for preventing fuel leakage of the vehicle and reducing the exhaust gas, a fuel pump 11 for pumping fuel contained in the cylinder 10 and fuel pumped by the fuel pump 11 are connected to be supplied to the engine. Fuel recovery lines 33 and 34 for recovering the fuel supplied to the fuel supply lines 31 and 32 and the engine 20, and one side of the fuel supply line 32 and the fuel recovery line 34, respectively. A first pressure regulator 51 connected to an injector 40 for supplying LPG fuel to the engine 20 in a liquid phase, and connected to one side of the fuel supply lines 31 and 32 and the fuel recovery lines 33 and 34; The oxygen sensor 71, the fuel adsorbent 72, and the oxidation catalyst 73 connect the muffler with the engine 20. Discharge lines 35 and 36 connected to one side of the discharge unit and one side of the fuel recovery line 34 and one side of the fuel adsorbent 72 are provided with a solenoid valve 60 and a second pressure regulator 52. It is configured to include.

Here, the first pressure regulator 51 corresponds to the pressure of the fuel pump 11 in the cylinder 10 at a pressure equal to or greater than the pressure of the fuel pump 11 and the fuel supply lines 31 and 32 and the fuel recovery line ( It is desirable to maintain the pressure of 33,34). This is for the LPG fuel in the fuel supply lines 31 and 32 and the fuel recovery lines 33 and 34 to maintain the liquid phase, and the first pressure regulator 51 includes the fuel supply lines 31 and 32 and the fuel recovery line ( The pressure of 33 and 34 is adjusted by applying a pressure of 5 bar to the pressure of the fuel pump 11 in the cylinder 10 to the fuel supply lines 31 and 32 and the fuel recovery lines 33 and 34. That is, when the pressure of the fuel pump 11 in the cylinder 10 is 2bar, the pressures of the fuel supply lines 31 and 32 and the fuel recovery lines 33 and 34 are 7 bar, which is 2 bar + 5 bar. By 51.

On the other hand, when the engine is stopped, the second pressure regulator 52 and the solenoid valve 60 reach the fuel adsorbent 72 for the fuel remaining in the injector 40, the fuel supply line 32, and the fuel recovery line 34. It is configured to.

The solenoid valve 60 is opened and closed in response to ignition on / off of the engine 20, and the second pressure regulator 52 adjusts the pressure of the discharge lines 35 and 36 when the engine 20 is stopped. The residual fuel is then led to the fuel adsorbent 72. In addition, the second pressure regulator 52 adjusts the pressure to guide the fuel regenerated from the fuel adsorbent 72 to the fuel recovery line 34 when the engine 20 is started, and the fuel regenerated through the fuel recovery line ( 33,34). Here, the heating heater 74 may be further provided at the upper end of the fuel adsorbent 72 to help smooth regeneration of the adsorbed fuel.

The second pressure regulator 52 and the solenoid valve 60 as described above are repeatedly operated at every start after soaking, and light-off during cold start with the regeneration of the adsorbed fuel according to this configuration and operation. It causes the temperature rise of the three-way catalyst prior to reaching the temperature to help the catalyst to operate quickly.

According to the present invention as described above, in a vehicle using the LPLI system, a fuel that may leak into an intake manifold after driving the engine is connected to a fuel adsorbent and a solenoid valve and a pressure regulator provided in the discharge line. By adsorbing to the fuel adsorbent and enabling regeneration at cold start after engine start, there is an effect of preventing air pollution by suppressing excessive unburned hydrocarbons generated during high temperature restart and cold start.

In addition, there is an effect of improving the startability of the LPG vehicle as well as the quick operation of the three-way catalyst through a simple internal structure.

Although the present invention has been described in connection with a preferred embodiment, those of ordinary skill in the art will be able to easily make various changes and modifications without departing from the essential characteristics of the present invention. Therefore, the disclosed embodiments should be considered in descriptive sense only and not for purposes of limitation, and the true scope of the present invention is shown in the claims rather than the foregoing description, and all differences within the equivalent scope are included in the present invention. Should be interpreted as.

Claims (7)

Fuel leakage prevention and exhaust gas of an LPG liquid injection vehicle including a cylinder 10 containing LPG fuel, an engine 20 supplied with the LPG fuel, and a muffler for discharging combustion gas generated from the engine 20. In the device for abatement, A fuel pump 11 for pumping fuel contained in the cylinder 10; Fuel supply lines 31 and 32 connected to supply the fuel pumped by the fuel pump 11 to the engine 20 and a fuel recovery line 33 for recovering the excess fuel supplied to the engine 20; 34); An injector 40 connected to one side of the fuel supply line 32 and the fuel recovery line 34 and for supplying LPG fuel to the engine 20 in a liquid phase; A first pressure regulator (51) connected to the fuel supply lines (31, 32) and one side of the fuel recovery lines (33, 34); A discharge unit connecting the engine 20 and a muffler and having an oxygen sensor 71, a fuel adsorbent 72, and an oxidation catalyst 73; And Discharge lines 35 and 36 connected to one side of the fuel recovery line 34 and one side of the fuel adsorbent 72 and having a solenoid valve 60 and a second pressure regulator 52; Apparatus for preventing fuel leakage and exhaust gas reduction of the LPG liquid injection vehicle comprising a. The method of claim 1, The first pressure regulator 51 corresponds to the pressure of the fuel pump 11 in the cylinder 10 at a pressure equal to or greater than the pressure of the fuel pump 11 and the fuel supply lines 31 and 32 and the fuel recovery line 33, respectively. A device for preventing fuel leakage and reducing exhaust gas of an LPG liquid injection vehicle, characterized by maintaining the pressure of 34). The method of claim 1, The solenoid valve 60 is a device for preventing fuel leakage and exhaust gas reduction of the LPG liquid injection vehicle, characterized in that the opening and closing in response to the ignition On / Off of the engine (20). The method of claim 2, The first pressure regulator 51 adjusts the pressure of the fuel supply lines 31 and 32 and the fuel recovery lines 33 and 34 to a pressure obtained by adding a pressure of 5 bar to the pressure of the fuel pump 11 in the cylinder 10. Apparatus for preventing fuel leakage and reducing exhaust gas of LPG liquid injection vehicle characterized in that. The method of claim 1, When the engine 20 is stopped, the second pressure regulator 52 and the solenoid valve 60 may stop the fuel remaining in the injector 40, the fuel supply line 32, and the fuel recovery line 34. Apparatus for preventing fuel leakage and exhaust gas reduction of the LPG liquid injection vehicle characterized in that it is provided to reach. The method of claim 5, The second pressure regulator (52) and the solenoid valve (60) is a device for preventing fuel leakage and exhaust gas reduction of the LPG liquid injection vehicle, characterized in that it operates repeatedly every start after soaking (Soaking). The method of claim 1, Apparatus for preventing fuel leakage and exhaust gas reduction of the LPG liquid injection vehicle, characterized in that the heating heater 74 is provided on the upper end of the fuel adsorbent (72).

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