KR20020045119A - Vaporizer of vehicle for liquefied petroleum gas - Google Patents

Abstract

PURPOSE: A pressure reducer of an LPG(Liquefied Petroleum Gas) vehicle is provided to prevent the delay or failure of hot or cold starting by surely cutting off the supply of fuel when an engine is restarted. CONSTITUTION: A fuel cut solenoid(140) is installed on a fuel inlet path(101) of a first pressure reducing chamber(110). The solenoid cuts off the inflow of fuel to the first pressure reducing chamber and the inflow of residual gas in the first pressure reducing chamber to a second pressure reducing chamber(120). If an engine is stopped, the inflow of fuel is stopped. When the engine is restarted, the fuel cut solenoid cuts off the inflow of fuel to the first pressure reducing chamber. Therefore, delay or failure of starting due to the leakage of fuel is prevented.

Description

Pressure reducer in liquefied petroleum gas vehicle {VAPORIZER OF VEHICLE FOR LIQUEFIED PETROLEUM GAS}

The present invention relates to a decompressor of a liquefied petroleum gas vehicle, and more particularly, a liquefied petroleum gas vehicle that can reliably shut off fuel even after the engine is turned off by attaching a fuel shutoff solenoid to a fuel inflow passage leading to the primary decompression chamber. It relates to a pressure reducer of.

Liquefied Petroleum Gas (LPG) fuel, a mixture of propane and butane, is commonly used in liquefied petroleum gas vehicles. do. Vehicles using such liquefied petroleum gas may improve the startability of the cold weather by using only the gaseous fuel contained in the bombe, but in the high speed region, the liquid fuel in the gaseous gas is more than the required fuel amount. Since the phase change to the fuel is not immediately followed, the output of the vehicle is not constant, and there is a problem in that driving performance is poor or normal driving is impossible. In order to solve this problem, a pressure reducer is used. The pressure reducer is a device for preheating liquid fuel to coolant and converting it into a gaseous fuel having a predetermined pressure.

A fuel device of a general liquefied petroleum gas vehicle, as shown in FIG. 1, vaporizes liquid gas fuel in two stages from a cylinder 1 for storing liquid and gaseous LPG gas fuel under high pressure. The pressure reducer 4 is connected to the pipe. A fuel filter (2) (2a) and a solenoid valve (3) (3a) are provided between the cylinder (1) and the pressure reducer (4). This solenoid valve 3 (3a) is a valve which can prevent the outflow of fuel. The pressure reducer 4 is connected to a mixer 5 which mixes external air and vaporized gas introduced through the air cleaner 6 with each other. The mixer 5 is connected to supply the intake manifold 7a to the engine 7 through the throttle valve 5a. Several sensors and valves are mounted on the connection pipe.

The detailed structure of the pressure reducer 4 which concerns on a conventional Example is largely divided into the primary pressure reduction chamber 10 and the secondary pressure reduction chamber 20, as shown in detail in FIG. The primary pressure reducing chamber 10 includes a primary valve 12, a primary valve lever 14, a primary diaphragm 16, a primary diaphragm spring 18, and the like, which are primary pressure regulating means. Also, the secondary pressure reducing chamber 20 also includes secondary pressure regulating means such as a secondary valve 22, a secondary valve lever 24, a secondary diaphragm 26, a secondary diaphragm spring 28, and the like. It is provided. Here, the gas inlet pipe 30 is connected to the inlet of the primary decompression chamber 10, and the slow cut solenoid 50 is installed at the outlet side secondary discharge pipe 42 to depressurize the primary. Some delivery of gaseous gas is controlled. In addition, the secondary valve 22 is installed on the connecting passage 11 of the primary and secondary pressure reducing chambers 10 and 20, and the secondary valve 22 is a secondary rock solenoid 60. It is controlled by opening and closing. The outlet side of the secondary pressure reduction chamber 20 is connected to the main discharge pipe 44 that can send the completely vaporized gas to the mixer (5).

The operation relationship of the conventional pressure reducer 4 configured as described above will be described with reference to FIGS. 1 and 2. First, when the solenoid valve 3 of the cylinder 1 side is opened, the liquid gas LPG is pressurized by the vapor pressure in the cylinder 1 and passes through the gas inlet pipe 30 of the primary pressure reducing chamber 10. The primary valve 12 is pushed and introduced into the primary pressure reducing chamber 10 to be decompressed to a gaseous state. When the inflow of fuel continues and the pressure of the primary pressure reduction chamber 10 becomes higher than 0.3 kg / cm <2>, the primary diaphragm 16 will be pushed upwards. At this time, the primary valve lever 14 is pulled up to close the primary valve 12 to block the inflow of fuel. After that, when the fuel gas is consumed and the gas pressure of the primary decompression chamber 10 is 0.3 kg / cm 2 or less, the force of the primary diaphragm spring 18 becomes greater than the gas pressure and the primary diaphragm 16 moves downward. Go down. At this time, the primary valve lever 14 is pushed down to open the primary valve 12. Therefore, the primary decompression chamber 10 functions to reduce the pressure of the fuel to about 0.3 kg / cm 2 so as to satisfy this in terms of fuel consumption and output. This is because the fuel from the cylinder 1 is high in pressure, so that it is difficult to control the amount of fuel, the ejection amount is large, and the air-fuel ratio becomes too rich, and thus it is difficult to use it as it is.

On the other hand, the gas fuel adjusted to a pressure of 0.323 kg / cm 2 in the primary decompression chamber 10 enters the secondary decompression chamber 20 through the secondary valve 22 and is then decompressed again to an almost atmospheric pressure level. That is, the secondary diaphragm 26 raises upwards by the negative pressure generated in the venturi portion of the mixer 5 when the engine 7 is rotating. At the same time, the secondary valve lever 24 interlocked with the secondary diaphragm 26 is also raised to open the secondary valve 22 to introduce fuel. If the engine 7 is stopped, the inflow of fuel is stopped because the secondary lock solenoid 60 causes the secondary valve 22 to close. Therefore, the secondary pressure reducing chamber 20 serves to reduce the pressure to almost atmospheric pressure in order to prevent the fuel from flowing into the mixer 5 regardless of the amount of air entering the mixer 5.

However, if the secondary valve 22, which opens and closes the secondary decompression chamber 20 of the pressure reducer 4 when the engine is turned off while driving the vehicle, is damaged by fuel and contaminants, fuel leakage occurs. This causes problems in hot startability. This is because when the fuel leaked into the secondary valve 22 flows into the secondary decompression chamber 20, the fuel therein becomes too rich and restarts poorly.

Accordingly, the present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a liquefied petroleum gas vehicle which can improve hot or cold restartability by reliably cutting off fuel even after the start is turned off. It is to provide a pressure reducer.

BRIEF DESCRIPTION OF THE DRAWINGS The figure which shows the whole structure of the fuel apparatus of the general liquefied petroleum gas vehicle.

2 is a cross-sectional view showing the structure of a pressure reducer of a conventional liquefied petroleum gas vehicle.

3 is a cross-sectional view showing the structure of a pressure reducer of a liquefied petroleum gas vehicle according to the present invention.

※ Explanation of codes for main parts of drawing

100: pressure reducer, 101: fuel inflow passage,

110: first decompression chamber, 120: second decompression chamber,

122: secondary valve, 124: secondary valve lever,

126: secondary diaphragm, 128: secondary diaphragm spring,

130: fuel inlet pipe, 140: fuel shutoff solenoid.

The pressure reducer of the liquefied petroleum gas vehicle according to the present invention for achieving the above object comprises a first decompression chamber capable of vaporizing liquid gas fuel by a first pressure at a predetermined pressure, and a gas fuel passing through the first decompression chamber. In the pressure reducer of the liquefied petroleum gas vehicle comprising a second pressure reducing chamber capable of completely vaporizing the second pressure to the atmospheric pressure to a second pressure, the fuel inlet passage of the first pressure reducing chamber when the start of the vehicle is turned off It is characterized in that it further comprises a fuel shutoff solenoid which can be blocked at the source to prevent the leakage of gaseous fuel into the decompression chamber.

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

3 is a cross-sectional view showing the structure of a pressure reducer of a liquefied petroleum gas vehicle according to the present invention. In the drawings, a part of the same configuration as in the prior art will be omitted, and a detailed description thereof will be omitted to avoid duplication. In addition, when it is necessary to quote the general components, the reference numerals and names shown in FIG. 1 are used as they are.

In the drawing, the pressure reducer 100 of the present embodiment is divided into a first pressure reducing chamber 110 and a second pressure reducing chamber 120. In the first pressure reducing chamber 110, a primary valve (not shown), a primary valve lever, a primary diaphragm, and a primary diaphragm (not shown) are used to reduce the gas (LPG) fuel flowing through the gas inlet pipe 130 to the primary. Primary pressure regulating means such as a fram spring or the like is included. The second pressure reducing chamber 120 also includes a secondary valve 122, a secondary valve lever 124, a secondary diaphragm 126, a secondary diaphragm spring 128, and the like, which are secondary pressure regulating means. do.

In particular, in this embodiment, the fuel cutoff solenoid on the fuel inlet passage 101 of the first decompression chamber 110 is generally separate from the solenoid 3 installed between the cylinder 1 and the pressure reducer (4 in FIG. 1). (Fuel Cut Solenoid) 140 is further provided. This not only prevents residual gas in the first decompression chamber 110 from flowing into the second decompression chamber 120 while the engine is turned off after driving, and also prevents inflow of gaseous fuel into the first decompression chamber 110. It is intended to be blocked at source.

It looks at the operation relationship of the pressure reducer 100 of the liquefied petroleum gas vehicle according to this embodiment provided as described above. First, when the engine 7 is started, the solenoid valve 3 on the cylinder 1 side is opened, and the liquid gas (LPG) fuel is pumped by the vapor pressure in the cylinder 1, and then the gas inlet tube 130 is opened. 1 flows into the decompression chamber 110. The gas introduced in this way is reduced and vaporized in a first step to maintain a pressure of about 0.3 kg / cm 2 by the opening and closing action of the primary pressure adjusting means (not shown).

Thus, the gas fuel depressurized in the first stage in the first decompression chamber 110 is introduced into the second decompression chamber 120 by lifting up the secondary valve 122 located in the connection passage 102, and then the second stage at almost atmospheric pressure level. It is decompressed and completely vaporized. That is, the secondary diaphragm 126 rises upward by the negative pressure generated in the venturi part of the mixer 5 according to the rotational force of the engine 7, and the secondary valve lever interlocked with the secondary diaphragm 126. 124 also goes up to open the secondary valve 122 to introduce the fuel.

If the engine 7 is stopped while driving the vehicle, the secondary lock solenoid (not shown) causes the secondary valve 122 to close, so that the inflow of fuel is stopped. Furthermore, in the present embodiment, since a separate fuel shutoff solenoid 140 is further provided on the fuel inflow passage 101 of the first decompression chamber 110, the secondary valve 122 may be, for example, contaminated or the like. Damage to the first decompression chamber 110 to prevent the leakage of residual gas, as well as to prevent the inlet of gaseous fuel inlet itself into the first decompression chamber (110).

Therefore, when the engine is restarted after stopping the engine, the fuel concentration may be thickened or lean due to the leakage of fuel, thereby preventing the engine from starting or slowing down.

According to the present invention described above, by reliably shutting off the fuel when the engine is restarted after the engine is stopped, it is possible to prevent a phenomenon in which hot or cold start is delayed or not at all, thereby further improving the merchandise and safety.

Claims (1)

A first decompression chamber capable of vaporizing the liquid gas fuel by a first pressure at a predetermined pressure, and a second decompression chamber capable of completely vaporizing the gas fuel passing through the first decompression chamber to an atmospheric pressure level completely; In the pressure reducer of the liquefied petroleum gas vehicle, The fuel inlet passage of the first decompression chamber further includes a fuel shutoff solenoid which can be blocked at the source to prevent the leakage of gas fuel into the first and second decompression chambers when the vehicle is turned off. Pressure reducer.