KR100648080B1 - Pressure regulating valve for improving canister performance - Google Patents

Abstract

A pressure control valve is provided to prevent damage of a fuel tank and prevent atmospheric contamination, by delaying or preventing negative pressure generated from a fuel tank during canister purge control. A pressure control valve(200) is arranged at a tank port of a canister(100) in such a manner that the pressure control valve is communicated to a gas outlet line(11) connected to a fuel tank. The pressure control valve delivers evaporative gas into the canister through a positive pressure open valve(220) using a diaphragm(221) if the pressure applied to the fuel tank is positive pressure when fuel is injected. The pressure control valve gradually delays small amount of evaporative gas and supplies evaporative gas into the canister through an orifice hole(214) communicated to the canister if the pressure is negative pressure generated in case of purge control.

Description

Canister Purge the efficiency improvement pressure control valve

1 is a block diagram of a control system for a general fuel evaporation gas.

2 is a configuration diagram showing a control system for fuel evaporation gas of the present invention.

Figure 3 is a partial cross-sectional view showing a canister equipped with a pressure control valve of the present invention.

Figure 4a, b is a cross-sectional view showing the operating state of the pressure control valve of the present invention.

<Description of the code for the main part of the drawing>

10: fuel tank 11: gas drawing line

12: air injection line 12a: air filter

13: purge line 30: combustion chamber

40: electronic control device 50: purge control valve

100: canister 120: air port

130: purge port 140: tank port

150: activated carbon 200: pressure control valve

210: body cover 211: interior space

213: injection hole 214: orifice hole

220: constant pressure release valve 221: diaphragm

222: elastomer 223: sealing plate

230: top cover 231: air outlet

240: vent 241: body

242 filter 243 cover

The present invention relates to a pressure regulating valve for improving performance of a canister, and more particularly, to evaporating fuel while suppressing external damage to a fuel tank by delaying and preventing negative pressure generated in a fuel tank during canister purge control. The present invention relates to a pressure control valve for improving the performance of a canister to delay leakage and prevent air pollution.

Inside the vehicle's fuel tank, the stored gasoline fuel is sent to the combustion chamber by the fuel pump and only 60% of the fuel received is burned and the remaining unburned fuel is returned to the fuel tank. do.

At this time, the returned fuel receives the heat of the engine when staying in the engine and rises to a certain temperature or more to generate gasoline boil-off gas, and another cause of the boil-off gas is the temperature inside the fuel tank due to radiant heat in the atmosphere. Gasoline is also generated when gasoline rises or fuels inside the fuel tank.

Thus, when the hydrocarbon (HC) is released into the atmosphere as the main component of the boil-off gas, it causes serious air pollution by the hydrocarbon, causing problems due to genetic modification of animals and plants.

 Therefore, at present, the evaporated gas (HC) generated in the fuel tank is introduced into the intake system, mixed with newly supplied air, and burned in the combustion chamber to strictly limit the amount of hydrocarbon (HC) emission, which is the main cause of environmental pollution, Carbon Canisters have been proposed to improve the efficiency.

These canisters function as a reservoir for storing gasoline boil-off gas generated in the fuel tank, and at the same time, the collected gasoline boil-off gas is sent to the combustion chamber of the engine at an appropriate time and combusted in the engine.

The evaporative emission control system equipped with such a general canister is as follows.

1 is a diagram illustrating a general fuel evaporation gas control system. As shown in FIG. 1, a gas lead-out line 11 is connected to one side of a fuel tank 10 in which fuel is stored, and a tank port of the canister 100. Mounted in communication with the 140 and the inside of the canister 100 is filled with granular activated carbon 150 so that the evaporated gas introduced from the fuel tank 10 can be adsorbed.

In addition, the purge line 13 for discharging the evaporation gas adsorbed on the activated carbon 150 on one side of the canister 100 is communicated to the intake pipe between the throttle body and the cylinder combustion chamber 30, the middle of the canister 100 Is equipped with a purge control valve 50 which separates the evaporated gas collected from the activated carbon 150 into the intake pipe according to the condition. The purge control valve 50 is connected to an electronic control device. The valve is opened and closed under the control of the controller.

Accordingly, when the fuel evaporates from the fuel tank 100 and flows into the gas drawing line 11, when the pressure is higher than a predetermined vapor pressure, the fuel is supplied to the canister 100 and the introduced boil-off gas is activated carbon 150 of the canister 100. Adsorbed on the particle surface.

In addition, the purge control valve 50 is opened according to the command of the electronic controller, so that the evaporated gas collected in the canister 100 is separated from the activated carbon 150 and enters the combustion chamber 30 of the cylinder through the intake pipe. Combustion process, at this time, the air injection line 12 is installed on the other side of the canister (100) and the air filter (12a) is installed in communication with the outside atmosphere by the purge air (Purge air) using the negative pressure of the engine By drawing the outside air through the desorbed boil-off gas in the activated carbon 150, it is supplied to the combustion chamber 30 of the engine through the purge port 130 to suppress the discharge to the atmosphere.

This control is performed so that the purge control valve 50 is kept closed by the electronic control device when the engine is idle and in warm air operation. In other cases, the purge control valve 50 is opened so that the combustion chamber is opened in the canister 100. The negative pressure of 30 affects the evaporated gas is separated from the activated carbon 150 and flows into the intake pipe.

However, the fuel evaporation gas control system according to the prior art is to pressurize the outside air to the canister 100 by using the negative pressure inside the combustion chamber 30 to desorb the evaporated gas from the activated carbon 150, in this case the air injection When the outside air is pumped through the line 12 and the air filter 12a, when excessive dust or foreign matter accumulates inside the air filter 12a or the air injection line 12, the negative pressure is stored in the fuel tank 10. As it is generated, there is a problem in that the fuel tank 10 is externally damaged by generating a shape deformation phenomenon in which the crack is generated and the fuel tank 10 is crushed.

In addition, the air injected through the air injection line 12 is permeated through the activated carbon 150 filled in the canister 100 to pressurize the boil-off gas adsorbed with a large amount of dust to the purge line 13, There was a problem of accelerating the negative pressure of the fuel tank 10 by causing clogging of the purge line 13.

As such, when the air injection line 12 is blocked, the pressure in the fuel tank 10 may be displaced lower than atmospheric pressure by not performing the function of the canister 100, and thus the evaporation through various valves attached to the fuel tank 10 may occur. There was a problem that the gas is released into the atmosphere causing air pollution.

In addition, when a negative pressure is generated in the fuel tank 10, the pressure inside the fuel tank 10 is lowered, thereby preventing the fuel from being supplied sufficiently during high-speed driving of the vehicle, preventing the vehicle from driving safely and generating engine misfire. There was a problem that serious damage to the driving device of the vehicle, such as excessive load on the catalytic device.

Accordingly, an object of the present invention is to install a pressure regulating valve in the tank port for supplying the boil-off gas of the fuel tank to the canister side to pressurize the boil-off gas into the combustion chamber through the purge port without excessively under-pressure when the negative pressure is generated. By preventing the negative pressure of the fuel tank, it is possible to prevent external damage of the fuel tank. This is because the pressure of the boil-off gas is slowly moved through the pressure regulating valve so that the pressure inside the fuel tank under negative pressure is 2 kPa. The delay of 3 ~ 5 seconds to ~ 3.5kPa delays the maximum negative pressure applied to the fuel tank, thereby delaying the extreme situation where the fuel tank may be damaged.

In addition, another object of the present invention is to properly control the vapor pressure generated inside the fuel tank through the orifice hole to prevent the discharge of a large amount of boil-off gas into the atmosphere to prevent air pollution by the hydrocarbon (HC) of the boil-off gas There is to help.

In addition, another object of the present invention is to delay and maintain the pressure in the canister and the fuel tank to an appropriate pressure state so that the fuel can always be properly supplied even during the high speed driving of the vehicle to ensure safe driving of the vehicle and smooth driving of the peripheral drive device of the vehicle. It is to enable the drive.

In order to achieve the object of the present invention, the canister of the fuel apparatus of the present invention is provided with an air injection line having an air filter and introducing external air therebetween so as to communicate with a gas drawing line and a purge line connecting the fuel tank and the combustion chamber, respectively. It is installed to recover the boil-off gas inside the fuel tank by the negative pressure generated by the driving of the engine, collect it in the activated carbon filled in the inside, transfer the boil-off gas to the combustion chamber and burn it to suppress the emission of the boil-off gas in the air. In the canister of a fuel device,

Install a pressure control valve in the tank port of the canister so as to communicate with the gas withdrawal line connected to the fuel tank, the pressure control valve is to open the positive pressure using the diaphragm installed inside when the pressure applied to the fuel tank at the constant pressure It is configured to supply a small amount of evaporated gas to the inside of the canister through the orifice hole formed to communicate with the inside of the canister when the evaporation gas is vented into the canister and the negative pressure generated during the purge control through the valve. do.

In addition, the pressure control valve is installed to be in communication with the canister at the same time the inlet hole formed to be spaced apart in the lower side of the inlet and the inlet hole of the hollow tube coupled to the tank port of the canister perpendicular to the inner center, but the gas outlet line on the outer peripheral surface A valve body forming a tank port coupled to and in communication with the orifice hole, an upper cover covering the upper side of the valve body to form a sealed inner space in the valve body, and an inlet opening of the valve body. The diaphragm of the diaphragm, which is integrally coupled to the outer circumference of the sealing plate to selectively open and close the valves, is fixed to the inner circumferential surface of the valve body and the upper cover so that the inner space of the valve body is partitioned up and down, It is possible to pressurize the sealing plate elastically through an elastic body to When the negative pressure and the positive pressure occurs in the negative portion, the positive pressure opening valve for selectively closing and opening the inlet, the upper surface of the upper cover is in communication with the inner space and coupled to the air outlet protruding to the outside partitioned by the diaphragm It is characterized by consisting of a vent for helping the operation according to the displacement of the pressure of the diaphragm by passing the flow of air by communicating the internal space with the outside.

In addition, the vent is a body that is coupled to the outer periphery of the air outlet, the filter is installed on the inner peripheral surface of the body to purify and permeate the air, and the air permeated through the sealed upper part of the body through the filter It is characterized by consisting of a cover to be vented.

 If described in more detail with reference to the accompanying drawings, preferred embodiments of the present invention as follows.

Figure 2 is a block diagram showing a control system of the fuel evaporation gas of the present invention, Figure 3 is a partial cross-sectional view showing a canister equipped with a pressure control valve of the present invention, Figure 4a, b is the operation of the pressure control valve of the present invention It is sectional drawing which showed state.

First, as shown in Figures 2 to 4, the configuration of the canister to which the pressure control valve for improving the performance of the canister of the present invention is applied, the canister for evaporating gas through a gas drawing line 11 connected to the fuel tank 10 and installed. (100) After the transfer to the inside can be collected in the activated carbon 150 filled in the canister 100, purge line 13 connected to the combustion chamber 30 and the purge port communicating with the interior of the canister (100) It is connected to the 130 to desorb the boil-off gas collected in the activated carbon 150 by using the negative pressure generated when the engine is driven to transfer the boil-off gas to the combustion chamber 30 through the purge line 13 to be burned. .

At this time, the air injection line 12 to the air port 120 formed on the side of the purge port 130 of the canister 100 for smooth aeration of the boil-off gas desorbed from the activated carbon 150 to the purge port 130 By connecting the external air is configured to enter into the canister (100).

In the canister configured as described above, the pressure control valve for improving the performance of the present invention has an air filter 12a and an air injection line 12 for introducing external air, and connects the fuel tank 10 to the combustion chamber 30. The lead line 11 and the purge line 13 are installed in communication with each other to recover the boil-off gas existing in the fuel tank 10 through the negative pressure generated by the engine driving and to the activated carbon 150 filled therein. In the canister of a fuel apparatus that suppresses the release of fuel evaporated gas in the atmosphere by transferring the boiled gas to the combustion chamber (30) after combustion, thereby causing combustion.

The pressure control valve 200 is installed on the upper portion of the canister 100 so as to be in communication with the gas drawing line 11 connected to the fuel tank 10, but the pressure control valve 200 is fuel tank 10 when fuel is injected. When the pressure applied to the positive pressure is a negative pressure generated during the purge control through the boil-off gas through the constant pressure opening valve 220 using the diaphragm 221 installed therein of the canister 100 Through the orifice hole 214 formed in communication with the inside is configured to be able to supply a small amount of evaporated gas into the canister 100 to be delayed slowly.

In addition, the pressure control valve 200 forms a tank port 140 in communication with the gas lead-out line 11 of the fuel tank 10, the inside of the valve formed an orifice hole 214 in communication with the canister 100. An upper cover 230 in which an inner space 211 is formed between the main body 210 and the valve body 210 by covering an upper portion of the valve body 210, and an inner space 211 of the upper cover 230. And a positive pressure release valve 220 which is opened to supply the vapor gas when the negative pressure is generated during the purge control and to supply the boil-off gas into the canister 100 when the positive pressure is generated, and the positive pressure release valve 220. It is installed on the upper surface of the upper cover 230 so that the operation of the smoothly consists of a vent 240 to allow the outside air to exchange with the internal space (211).

Here, the valve body 210 is coupled to the tank port of the canister 100, the orifice hole 214 formed to be spaced apart from the inlet 213 of the hollow tube formed perpendicular to the inner center and the side lower portion of the inlet 213. It is installed so as to be in communication with the canister 100 at the same time on the outer circumferential surface to form a tank port 140 is coupled to communicate with the gas outlet line 11 to communicate with the orifice hole 214.

In addition, the upper cover 230 to cover the upper side of the valve body 210 to form a closed inner space 211 inside the valve body 210.

Further, the positive pressure release valve 220 is a diaphragm-like diaphragm 221 integrally coupled to the outer periphery of the sealing plate 223 for selectively opening and closing the inlet 213 inlet of the valve body 210, the valve body ( It is fixed to the inner peripheral surface of the boundary 210 and the upper cover 230 so as to partition the inner space 211 of the valve body 210 up and down while interposing the elastic body 222 between the sealing plate 223 and the upper cover 230. The sealing plate 223 is elastically pressed to selectively block and open the inlet 231 when negative pressure and positive pressure occur.

In addition, the vent 240 is connected to the air outlet 231 which communicates with the inner space 211 on the upper surface of the upper cover 230 and protrudes to the outside to separate the inner space 211 partitioned by the diaphragm 221. By communicating with the air flow through the diaphragm 221 to facilitate the operation according to the displacement of the pressure.

At this time, the vent 240 is the body 241 is coupled to the outer periphery of the air outlet 231, the filter 242 is installed on the inner peripheral surface of the body 241 to purify and permeate the air, and The cover 243 is configured to seal the opened upper portion of the body 241 to allow air to pass through the filter 242.

Referring to the operation of the present invention as follows.

First, when the fuel injection does not cause clogging due to dust or foreign matter in the air filter 12a and the air injection line 12, the evaporated air is smoothly supplied to the internal space 211 of the pressure control valve 200 at a constant pressure. When the diaphragm 221 of the diaphragm-shaped disk method is moved upward by the pressure of the boil-off gas, the sealing plate 223 opens the inlet of the inlet 213 so that the boil-off gas is injected through the inlet 213. It is collected in the activated carbon 150 inside.

Then, the combustion chamber through the purge line 13 installed in communication with the purge port 130 of the canister 100 by the evaporation gas trapped in the activated carbon 150 is desorbed by the negative pressure generated during the purge control by the driving of the engine. After the supply of the boil-off gas to the (30) side is burned.

Here, the air injected at a predetermined pressure by drawing external air into the canister 100 through the air injection line 12 helps the desorption of the boil-off gas collected in the activated carbon 150 while passing through the activated carbon 150.

In this way, the evaporated gas is smoothly supplied with the evaporated gas in the canister 100 when the flow of pressure is maintained because the foreign matter is not blocked in the air filter 12a and the air injection line 12, and is burned.

On the contrary, when the air filter 12a or the air injection line 12 is clogged with dust or foreign matter and cannot draw outside air into the canister 100, a negative pressure is applied to the internal space 211 of the pressure control valve 200. When generated, the sealing plate 223 of the positive pressure opening valve 220 blocks the inlet of the inlet 213 by the diaphragm 221 in the form of a diaphragm, and further, the boil-off gas is supplied to the canister 100 through the inlet 213. While only a small amount of evaporated gas leaks through the orifice hole 214 into the canister 100 to delay and restrain the negative pressure inside the fuel tank so that the fuel tank 10 is crushed or cracked due to the negative pressure. It prevents the phenomenon that occurs.

At this time, when a negative pressure is generated in the pressure control valve 200, a vent having a built-in filter 242 to vent air with external air in the air outlet 231 protruding from the upper cover 230 to help the diaphragm 221 operate correctly. By installing the 240, the diaphragm 221 partitioning the inner space 211 up and down by allowing the purged air, excluding dust and foreign matter, to be directed to the inner space 211 side of the pressure control valve 200 is the fuel tank (10) Properly operate in accordance with negative pressure or static pressure generated inside.

As described above, the canister performance improvement pressure control valve of the present invention is to install a pressure control valve in the tank port for supplying the boil-off gas of the fuel tank to the canister side to discharge only a small amount of boil-off gas into the canister when the negative pressure occurs It is possible to prevent external damage to the fuel tank by suppressing the occurrence of negative pressure in the fuel tank by feeding the boil-off gas into the combustion chamber through the purge port without excessively underpressure being applied to the inside of the fuel tank.

In addition, another effect of the present invention is that the pressure of the evaporation gas is slowly carried out through the pressure regulating valve, so that the internal pressure of the fuel tank under negative pressure reaches 2 kPa to 3.5 kPa by 3 to 5 seconds. It is effective in delaying the maximum negative pressure applied to the fuel tank to delay the extreme situation where the fuel tank may be damaged.

In addition, another effect of the present invention is to properly control the vapor pressure generated in the fuel tank through the orifice hole to prevent the large amount of evaporated gas to be discharged into the atmosphere to prevent air pollution by the hydrocarbon (HC) of the evaporated gas It is effective to make it possible.

In addition, another effect of the present invention is to delay and maintain the pressure in the canister and the fuel tank at an appropriate pressure state so that the fuel can be properly supplied at all times even when the vehicle is driving at a high speed, so that the smooth driving of the vehicle and the peripheral drive device of the vehicle are smooth. It is effective to allow driving.

Claims (3)

An air injection line 12 having an air filter 12a and introducing external air is installed and communicates with the gas drawing line 11 and the purge line 13 connecting the fuel tank 10 and the combustion chamber 30, respectively. By installing and recovering the boil-off gas existing in the fuel tank 10 through the negative pressure generated by the driving of the engine and shrouded in the activated carbon 150 filled therein, by transporting the boil-off gas to the combustion chamber 30 to burn it. In the canister of a fuel device that suppresses the emission of fuel evaporated gas into the atmosphere, The pressure control valve 200 is installed in the tank port of the canister 100 so as to be in communication with the gas drawing line 11 connected to the fuel tank 10, but the pressure control valve 200 is a fuel tank 10 when fuel is injected. ) When the pressure applied to the positive pressure is a negative pressure generated at the time of venting the evaporated gas into the canister 100 through the positive pressure opening valve 220 using the diaphragm 221 installed therein, and the canister 100. The pressure control valve for improving the performance of the canister, characterized in that configured to supply a small amount of evaporation gas through the orifice hole (214) in communication with the interior of the canister 100 by slowly delaying.   The method of claim 1, The pressure control valve 200, The canister 100 has an orifice hole 214 coupled to an upper surface of the canister 100 so as to be spaced apart from the inlet 213 of the hollow tube and formed at a lower side of the side of the inlet 213. It is installed to communicate at the same time but on the outer circumferential surface to form a tank port 140 coupled to communicate with the gas outlet line 11, but the valve body 210 to communicate with the orifice hole 214, and An upper cover 230 formed to cover the upper side of the valve body 210 to form a sealed inner space 211 in the valve body 210; The diaphragm-shaped diaphragm 221 integrally coupled to the outer circumference of the sealing plate 223 for selectively opening and closing the inlet 213 of the inlet 213 of the valve body 210 has a valve body 210 and an upper cover 230. The inner space 211 of the valve body 210 to be partitioned up and down while being fixed to the boundary inner circumferential surface, and the sealing plate 223 is elastically interposed between the sealing plate 223 and the upper cover 230 with an elastic body 222 interposed therebetween. Constant pressure open valve 220 to selectively block and open the inlet 231 when the negative pressure and the positive pressure to the inside of the fuel tank 10 to pressurize with, The air flows by communicating with the inner space 211 on the upper surface of the upper cover 230 and connected to the air outlet 231 protruding outside to communicate the inner space 211 partitioned by the diaphragm 221 with the outside. The pressure control valve for improving the performance of the canister, characterized in that consisting of a vent (240) to help the operation according to the displacement of the pressure of the diaphragm (221) by venting. The method of claim 2, The vent 240 is, A body 241 coupled to the outer periphery of the air outlet 231 and; A filter 242 installed on an inner circumferential surface of the body 241 to purify and transmit air; The pressure control valve for improving the performance of the canister, characterized in that the cover (243) configured to seal the opened upper portion of the body (241) to allow the air to pass through the filter (242).

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