KR20020040460A - vaporizer leak prevention device for LPG motor car - Google Patents

Abstract

PURPOSE: A device for preventing the leakage of a vaporizer for an LPG(Liquefied Petroleum Gas) vehicle is provided to enhance the reliability of a vehicle by preventing the degradation of restartability, to prevent the environmental pollution by minimizing the defect in restartability due to excess supply of fuel, and to improve productivity by compacting the structure. CONSTITUTION: A solenoid valve is installed in a fuel supply path(4c) for supplying LPG to a first pressure reducing chamber(4a) of a vaporizer(4). When an engine(6) is driven, the fuel supply path is opened by the solenoid valve. When the engine is stopped, the fuel supply path is closed by the solenoid valve. The solenoid valve is driven by an electrical signal. By closing the fuel supply path, the leakage of the fuel to the first pressure reducing chamber is prevented.

Description

Vaporizer leak prevention device for LPG motor car}

The present invention is to prevent the additional LPG fuel flow into the vaporizer (vaporizer) upon restarting immediately after the start of the vehicle using the LPG fuel by the excessive supply of fuel mixed with the clean air of the air cleaner side The present invention relates to a leak prevention device of an LPG fuel vaporizer for an automotive vehicle, which can prevent the restartability due to the rich.

More specifically, the LPG fuel in the primary pressure reducing chamber of the vaporizer rises momentarily due to the high temperature of the engine coolant when the engine is turned off while driving and leaks into the secondary pressure reducing chamber, so that LPG flows into the secondary pressure reducing chamber when the engine is restarted. The present invention relates to a leak prevention device of an LPG fuel vaporizer for an LPG vehicle which is prevented from dropping restartability due to flowing into the engine after being mixed with fuel.

In recent years, fuel prices are relatively low instead of gasoline or diesel used as fuel for automobiles, and the amount of automobiles using LPG (liquified petroleum gas) fuel is increasing due to the low content of carbon monoxide in exhaust gas due to complete combustion. The LPG fuel is a mixture containing propylene and butylene with respect to the main components of propane and butane and is easily decompressed by cooling or pressurization, and easily evaporated by heating or depressurization.

As shown in FIG. 1, the fuel supply apparatus of a conventional LPG vehicle includes a fuel tank 1 storing a high pressure LPG fuel, a filter 2 filtering impurities in the LPG fuel, and an engine cooling water. The preheater 3 preheats the feed fuel by heat dissipated during circulation, and the high temperature and high pressure LPG fuel passing through the preheater 3 is vaporized and maintained at a constant pressure, and the amount of vaporization is adjusted according to the increase or decrease of the engine load. And a mixer 5 for mixing the gas fuel vaporized in the vaporizer 5 and the clean air passed through the air cleaner (a typical complete combustion mixing ratio is 15: 3).

In the fuel supply apparatus of the above-described LPG vehicle, when the LPG fuel is supplied to the fuel inlet passage 4c of the vaporizer 4 by vapor pressure while maintaining the pressure in the fuel tank 1, the primary decompression chamber of the vaporizer 4 is supplied. In (4a), the LPG fuel is decompressed to 0.3 kg / cm 2 and sent to the secondary decompression chamber (4b). In the secondary decompression chamber (4b), the LPG fuel is expanded to re-decompression to atmospheric pressure. The inflated fuel and clean air are mixed and then introduced into the combustion chamber of the engine 6.

However, when the engine is turned off due to carelessness of the driver while driving, the above-mentioned vaporizer 4 is surrounded by the engine coolant that has maintained the predetermined temperature (about 90 ° C) to about 130 ° C by the engine 6 heat. The liquid LPG fuel remaining in the primary pressure reduction chamber 4a of the vaporizer 4 is vaporized by the high temperature cooling water circulating.

The vaporized LPG fuel is forced to open the valve 7 for opening and closing the primary pressure reducing chamber 4a and the secondary pressure reducing chamber 4b by increasing the pressure to 0.7 kg / cm 2 due to the momentary expansion, 1 The vaporized expanded fuel in the secondary pressure reducing chamber 4a leaks to the secondary pressure reducing chamber 4b via the valve 7.

In this case, a problem occurs even when the driving is turned off while the vehicle is restarted immediately. That is, the secondary fuel pressure is reduced through the valve 7 in which the expanded fuel in the primary pressure reducing chamber 4a of the vaporizer 4 is opened due to the expansion of the fuel by the engine coolant that is heated to a high temperature as the engine 6 is stopped. As it leaks into the chamber 4b, it is rich with LPG fuel flowing from the primary decompression chamber 4a into the secondary decompression chamber 4b through the valve 7 which is interlocked and opened when the engine 6 is restarted. Since it is mixed as a state and then flows into the combustion chamber of the engine 6, the start is not smoothly taken in a timely manner. In particular, a novice driver is very embarrassed momentarily when restarting the vehicle after the vehicle is turned off at a traffic light.

In addition, due to the excessive supply of LPG fuel, there is a problem of polluting the atmosphere and the environment due to harmful exhaust gas discharged after incomplete combustion.

Accordingly, an object of the present invention is to prevent the LPG fuel from flowing into the vaporizer further when the LPG vehicle is turned off and then restart, and the restartability is due to the thickening caused by the excessive supply of fuel mixed with the clean air on the air cleaner side. As it prevents falling, it is to provide a leak prevention device of the LPG fuel vaporizer for automobiles to ensure the quality stability of the product and in particular to increase the reliability from novice drivers.

Another object of the present invention is to provide a leak prevention device of an LPG fuel vaporizer for automobiles, which prevents air and environmental pollution by minimizing emission of harmful exhaust gas by preventing restartability due to excessive supply of fuel. .

It is still another object of the present invention to provide a leak prevention device for an vaporizer for an LPG automobile, which can improve productivity due to the simplified structure.

1 is a schematic diagram of a fuel supply system for an LLP fuel vehicle according to the prior art,

Figure 2 is a schematic diagram of a fuel system to which the leak prevention device of the vaporizer for LPG automobile according to the present invention is applied,

Figure 3 is a state of use of the leak prevention device of the vaporizer for LPG automobile according to the present invention.

* Explanation of symbols used in the main part of the drawing

One; Fuel tank 2; filter

3; Pre-heater 4; Vaporizer

4a; Primary decompression chamber 4b; Secondary decompression chamber

4c; Fuel inlet passage 5; mixer

6; Engine 7; valve

8; Solenoid valve

An object of the present invention as described above, in the LLP fuel vehicle having a vaporizer for vaporizing the fuel flowing into the engine and the primary pressure-reduction chamber and the secondary pressure-reduction chamber by the opening of the valve interlocked when the engine is driven, the above-mentioned vaporizer It is installed in the fuel inlet passage for supplying LPG fuel to the primary decompression chamber of the engine, and opens the fuel inlet passage when the engine is running, and closes the fuel inlet passage when the engine is stopped to prevent additional LPG fuel from entering the vaporizer. It is achieved by providing a leak prevention apparatus of an vaporizer for an LLP fuel automobile, characterized in that it comprises a means.

According to a preferred embodiment, a solenoid valve may be used to close the fuel inlet passage by driving upon application of an electrical signal to the fuel opening and closing means.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, which are intended to be described in detail to be easily carried out by those skilled in the art to which the present invention pertains, and thus the present invention It does not mean that the technical scope of the is limited.

As shown in FIGS. 1 and 2, the primary pressure reducing chamber 4a and the secondary pressure reducing chamber 4b communicate with each other by a valve 7 which is opened by a negative pressure when the engine 6 is driven. The present invention is applied to an automobile using an LLP fuel having a vaporizer 4 for depressurizing and vaporizing fuel flowing into the engine 6.

Therefore, according to a preferred embodiment of the present invention, it is provided in the fuel inlet passage 4c for supplying the LPG fuel to the primary decompression chamber 4a of the vaporizer 4 described above, and the fuel inlet passage when the engine 6 is driven. (4c) is opened, and when the engine 6 is stopped, the fuel inflow passage (4c) is closed to drive the electric signal applied when the electrical signal applied to prevent the additional LPG fuel flow into the primary pressure-reduction chamber (4a) A solenoid valve 9 for closing the inflow passage 4c is provided.

Hereinafter, a method of using a leak prevention apparatus of an LPG automobile vaporizer according to the present invention will be described with reference to the accompanying drawings.

As shown in Fig. 2, the start switch is turned on to drive the engine of the LPG vehicle, and thus, the fuel decompression passage 4c is applied to the primary decompression chamber 4a of the vaporizer 4 through the aforementioned fuel inflow passage 4c. The incoming LPG fuel flows into the secondary pressure reducing chamber 4b via the open valve 7, and the expanded LPG fuel flowing into the secondary pressure reducing chamber 4b passes through the air cleaner and the mixer. After mixing in (5) it is introduced into the combustion chamber of the engine (6). At this time, the solenoid valve 8 installed in the fuel inlet passage 4c maintains an initial state of opening the fuel inlet passage 4c.

On the other hand, as shown in Fig. 3, when the starting of the car is turned off while driving (refers to the case of OFF), the solenoid valve provided in the fuel inlet passage (4c) for supplying LPG fuel to the above-described primary pressure-reduction chamber (4a) As the electrical signal is applied to (8), the fuel inflow passage 4c is closed, which causes additional LPG fuel to flow into the primary decompression chamber 4a of the vaporizer 4 when the engine 6 is stopped. Is prevented.

Therefore, when the start switch is turned on immediately after the start of the engine 6 is turned off, the LPG fuel is additionally introduced into the vaporizer 4 by the solenoid valve 8 installed in the fuel inflow passage 4c. As a result, the LPG fuel remaining inside the primary decompression chamber 4a of the vaporizer 4 is temporarily expanded due to the high temperature of the engine coolant when the engine is stopped to prevent leakage into the secondary decompression chamber 4b.

For this reason, even when the engine is turned off while driving and attempting to restart immediately, the LPG fuel introduced into the above-mentioned vaporizer 4 is expanded in the primary pressure reducing chamber 4a and the secondary pressure reducing chamber 4b, and then the air cleaner is removed. The clean air passed through is mixed at an appropriate ratio and supplied to the combustion chamber of the engine 6 so that the start is timely.

As mentioned above, according to a preferable embodiment, it has the following advantages.

Since the LPG fuel is prevented from inflowing additional LPG fuel to the vaporizer immediately after the LPG vehicle is turned off, the restartability is prevented due to the thickening caused by the excessive supply of fuel mixed with clean air on the air cleaner side. It ensures the quality stability of the system and can increase the reliability from the novice drivers.

In addition, it is possible to prevent air and environmental pollution by minimizing the emission of harmful exhaust gas by preventing the restartability due to the excessive supply of fuel.

In addition, the structure can be improved due to the simplified structure.

Claims (2)

In an LLP fuel vehicle having a vaporizer for vaporizing fuel flowing into the engine, the primary pressure reducing chamber and the secondary pressure reducing chamber are connected to each other by the opening of an interlocking valve when the engine is driven: Installed in the fuel inlet passage for supplying LPG fuel to the primary decompression chamber of the vaporizer, the fuel inlet passage is opened when the engine is driven, and the fuel inlet passage is closed when the engine is stopped so that LPG fuel is additionally introduced into the vaporizer. An anti-leakage device for an vaporizer for an LPG automobile, characterized in that it comprises a fuel opening and closing means for preventing the leakage. 2. The leakage preventing device of an vaporizer for an LLP fuel automobile according to claim 1, wherein a solenoid valve for driving the electric signal to the fuel opening and closing means to close the fuel inlet passage is used.