KR101048656B1 - External Fuel Pump - Google Patents

Abstract

The present invention relates to an external fuel pump capable of supplying liquid and gaseous fuel inside the external fuel pump to the engine in the gas vehicle Elpia system, comprising a shaft having an eccentric drive portion formed therein to pump fuel supplied from a cylinder. A pump chamber configured to rotate the motor unit, a pump unit for pumping fuel using a rotational movement of the eccentric drive unit, and a pump inlet for shielding the outside of the pump unit and introducing fuel supplied from the bomb into the chamber chamber therein; The pump unit includes a plurality of chambers, some of the chambers having a gaseous inlet for sucking gaseous fuel from the chamber chamber, and others having a liquid inlet for sucking liquid fuel. do.

By using the external fuel pump as described above, liquid and gaseous fuels are smoothly supplied to the engine through the liquid inlet and the gaseous inlet, and thus the fuel oil level between the gas phase and the liquid phase is lowered by reducing the gas phase layer. Engine relief can be reduced by eliminating hindrances to the fuel supply.

Elpiy, External Fuel Pump, Vapor Phase, Fuel Supply, Liquid Intake, Vapor Intake

Description

External fuel pump {EXTERIOR TYPE FUEL PUMP}

The present invention relates to an external fuel pump, and more particularly, to an external fuel pump that is installed outside the cylinder in the gas vehicle Elpia system for supplying liquid fuel from the cylinder to the engine.

In general, a vehicle using liquefied petroleum gas (LPG) as a fuel supplies an engine with LPG fuel stored in a fuel tank by using a fuel pump. At this time, the amount of LPG supplied to the engine is adjusted by controlling the rotational speed of the fuel pump in consideration of the speed of the vehicle.

Recently, an engine of a liquefied petroleum injection (Liquefied Petroleum Injection, hereinafter referred to as `` elpia '') system has been developed in which the LPG is directly injected into the engine in a liquid state. As the Elpia-type engine uses liquid LPG fuel, it can improve the engine output by 10 to 20% and reduce the emission of pollutants compared to the conventional engine using gaseous fuel.

The present applicant has applied for a gas vehicle Elpia system for which an Elpia-type engine is applied to Korean Patent Application No. 10-2009-0073583 (filed Aug. 11, 2009, hereinafter referred to as 'prior art'). .

1 is a configuration of the gas vehicle lpaiyi system according to the prior art, Figure 2 is a cross-sectional view of the fuel pump shown in FIG.

As shown in Figure 1, the gas vehicle lpai system 1 according to the prior art is installed outside the cylinder (2), the multi-valve (3) installed in the cylinder (2), the cylinder (2) in which fuel is stored Fuel pump (4) and solenoid valve (8) connected to the multi-valve (3) and pumping out the fuel stored in the cylinder (2) through the fuel supply line (S) from the fuel pump (4) The liquid fuel supplied through the fuel cell is injected into the engine 5 and the cylinder 2 which are driven by the injector 5a and are supplied to the multi-valve 3 and the fuel pump 4. It comprises a pressure regulator (9) for reducing the pressure of the fuel finely injected from the engine (5) through the nozzle (6) and the fuel recovery line (R) and recovered to the cylinder (2).

As shown in FIG. 2, the fuel pump 4 in the ELPIA system 1 according to the related art configured as described above is formed on one side of the pump chamber 4a and the pump chamber 4a to form an outer cylinder. And a fuel inlet 4b for introducing the fuel supplied from (2) into the chamber chamber 4 'therein, and a motor 4c for generating pumping power to pump the fuel.

The fuel inlet 4b provided in the fuel pump 4 in the ELPAI system 1 according to the prior art allows the fuel chamber 4a of the pump chamber 4a to be easily introduced into the chamber chamber 4 'by gravity. It was installed at the upper side of the side.

At this time, the fuel introduced into the chamber chamber 4 ′ in the fuel pump 4 is heated by heat generated when the motor 4c is driven to evaporate in a gaseous state. As a result, the gaseous fuel is filled in the chamber chamber 4 ', and thus the gas phase layer B is formed on the liquid phase layer A, and the gas phase layer B gradually expands with time. At this time, since the pressure of the gas phase layer (B) is higher than the pressure of the liquid phase (A), the fuel pump (4) in the Elpia system according to the prior art by the pressure of the gas phase layer (B) inside the chamber chamber (13) This prevented the inflow of liquid fuel. Therefore, as the oil surface C between the liquid phase layer A and the gas phase layer B is lowered downward, the gas phase layer B prevents the liquid fuel from being supplied to the engine 5.

In addition, as the height of the fuel oil level flowing into the chamber chamber 4 'inside the fuel pump 4 changes when the vehicle vibrates, runs on a slope, or corners, the fuel of the conventional gas vehicle elpia system 1 is changed. The pump could not smoothly supply fuel to the engine 5, causing a problem in the engine 5 relief.

In particular, when the amount of fuel supplied to the engine 5 falls below the threshold value, the engine 5 is turned off during driving of the vehicle, thereby providing a cause of a traffic accident.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an external fuel pump that can supply the fuel in the liquid state and gaseous state inside the external fuel pump to the engine in the gas vehicle Elpia system. .

It is another object of the present invention to provide an external fuel pump that can prevent the liquid fuel oil level from being lowered continuously in the external fuel pump.

It is still another object of the present invention to provide an external fuel pump for selectively supplying a liquid fuel and a gaseous fuel to an engine based on a change in fuel level in an external fuel pump.

According to a feature of the present invention for achieving the object as described above, the present invention is a motor unit for rotating a shaft formed with an eccentric drive unit at the bottom to pump the fuel supplied from the cylinder, fuel by using the rotational movement of the eccentric drive unit A pump chamber for pumping the pump and shielding the outside of the pump portion, and the fuel inlet for forming the fuel inlet for introducing the fuel supplied from the cylinder into the chamber chamber, wherein the pump unit comprises a plurality of chambers, Some are provided with a gaseous inlet for sucking gaseous fuel from the chamber chamber, and others are provided with a liquid inlet for sucking liquid fuel.

The liquid inlet may be connected to a hose extending to a predetermined length toward a lower surface of the pump chamber to lower the suction position of the fuel introduced into the chamber.

The liquid inlet is formed to extend toward the lower surface of the pump chamber to lower the suction position of the fuel introduced into the chamber during the initial molding.

The gas phase intake port may be configured to suck the liquid fuel when the fuel oil level between the fuel in the liquid state and the fuel in the gas state is higher than the lower end of the gas phase intake port.

The gas phase suction port is configured to suck the gaseous fuel when the fuel oil level is lower than the gas phase suction port.

At least one gaseous inlet is provided, and when provided in plurality, are provided adjacent to each other or alternately provided with the liquid inlet.

The fuel inlet is characterized in that formed on the upper end of the side of the pump chamber.

The fuel inlet is characterized in that formed on the lower surface of the pump chamber.

As described above, the present invention forms the height of the liquid inlet and the gaseous inlet differently, and supplies the fuel in the liquid state to the engine when the liquid fuel oil level is in the normal range, and if the oil level is out of the normal range, Supply fuel to the engine together.

Therefore, the present invention can smoothly supply the liquid and gaseous fuel to the engine through the liquid inlet and the gaseous inlet.

In addition, the present invention can reduce the engine relief by supplying a gaseous fuel to the engine to reduce the gas phase layer, thereby lowering the fuel oil level between the gas phase layer and the liquid phase to interfere with fuel supply.

In particular, the present invention has the effect of preventing the cause of the traffic accident in advance by preventing the engine starting is stopped during the run due to the supply fuel shortage.

In addition, the present invention has the effect of improving the fuel efficiency by selectively supplying the fuel in the liquid state and gaseous state in accordance with the change in the height of the fuel oil level.

Hereinafter, an external fuel pump according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

In the present embodiment, the configuration of the gas vehicle elf system is described using the configuration of the prior art.

3 is a cross-sectional view of an external fuel pump according to a first embodiment of the present invention, and FIG. 4 is a perspective view illustrating a chamber of the external fuel pump shown in FIG. 3.

As shown in FIG. 3, the external fuel pump 10 according to the first embodiment of the present invention includes a motor unit 20 for rotating a shaft 23 having an eccentric drive unit 24 formed thereon to pump fuel. By using the rotational movement of the eccentric drive unit 24, the pump unit 30 pumping fuel and the outside of the pump unit 30 are shielded, and the fuel supplied from the cylinder 2 is provided with the chamber chamber 13 therein. It comprises a pump chamber 13 is formed with a fuel inlet 14 to be introduced into ').

The external fuel pump 10 according to the first embodiment of the present invention has a skeleton formed by the pump body 11, the motor portion 20 is installed on the upper portion of the pump body 11, the lower portion of the pump portion 30 is installed.

The upper side of the pump body 11 is coupled to the cover 12 for shielding the outside of the motor unit 20, the lower side is coupled to the pump chamber 13 for shielding the outside of the pump unit 30.

The pump chamber 13 is formed in a cylindrical shape with one side opened, and has a fuel inlet 14 connected to the fuel supply line S so as to introduce fuel supplied from the bomber 2 at one upper end thereof. .

The motor unit 20 is installed on the motor cover 21 and the pump body 11 to shield the outside to provide power to pump fuel (Brushless Direct Current Motor, hereinafter referred to as a motor) ) And a shaft 23 coupled to the inside of the motor 22 and having an eccentric drive unit 24 at the bottom thereof.

As shown in FIG. 4, the pump unit 30 includes five chambers 30a to 30e arranged at predetermined angles to pump fuel.

The number of the chambers 30a to 30e is not necessarily limited thereto, and may be variously changed to two or more according to conditions such as the size, pumping capacity, pumping speed, and pumping pressure of the external fuel pump 10. .

Each of the five chambers 30a to 30e has a plunger 31 for converting the rotational movement of the eccentric drive unit 24 into a linear reciprocating motion, and the linear reciprocating motion of the plunger 31. The diaphragm 32 for pumping the fuel introduced into the chamber chamber 13 'through the fuel inlet 14 of the pump chamber 13, and the diaphragm 32 is operated by pumping pressure. 13 ') first and second check valves 33 and 34 for sucking and discharging fuel therein and an inlet 35 through which fuel is sucked into the first check valve 33 from the chamber chamber 13'. Equipped.

As shown in FIG. 4, since the inlets 35 are provided for each of the chambers 30a to 30e, a total of five inlets are provided, one of which is a gaseous inlet for inhaling gaseous fuel. The four 35b to 35e are liquid intake ports for sucking liquid fuel.

The gas phase suction ports 35a and the liquid phase suction ports 35b to 35e are formed to have different heights.

In the present embodiment, the gas phase suction port 35a is formed to have the same height as the conventional suction port, and each of the liquid suction ports 35b to 35e lowers the suction position of the fuel even if the height of the fuel oil level is changed, thereby allowing the fuel to be in the liquid state. It is connected to the hose 36 extending in a predetermined length toward the lower surface of the pump chamber 13 so as to smoothly suck.

At this time, the length of the hose 36 is determined according to the experimental results of measuring the height of the fuel oil surface during the fuel pumping operation to suck the liquid fuel in the lower portion of the liquid layer.

As such, the external fuel pump 10 according to the present invention is connected to a gas inlet 35a for sucking gaseous fuel and a hose 36 having a predetermined length, and thus, a liquid inlet 35b for sucking liquid fuel. 35e), it is possible to selectively suck the liquid fuel and the gas fuel in accordance with the change in the height of the fuel oil level.

Hereinafter, the operation of the external fuel pump according to the first embodiment of the present invention will be described in detail with reference to FIGS. 5A to 5D.

5A to 5D are operation state diagrams of the external fuel pump according to the first embodiment of the present invention.

When the ignition key (not shown) of the vehicle is turned on and the battery power is supplied, the motor unit 20 of the external fuel pump 10 starts driving.

That is, as the motor 22 rotates, the shaft 23 rotates. Then, the plunger 31 provided in contact with the eccentric drive part 24 provided in the lower part of the shaft 23 converts the rotational motion of the eccentric drive part 24 into linear reciprocating motion.

In addition, the diaphragm 32 opens and closes the first and second check valves 33 and 34 by pumping according to the linear reciprocating motion of the plunger 31.

On the other hand, as the multi-valve 3 is opened by receiving battery power, fuel stored in the cylinder 2 is supplied to the external fuel pump 10.

Accordingly, the external fuel pump 10 introduces fuel into the chamber chamber 13 ′ through the fuel inlet 14 formed at the upper end side of the pump chamber 13, and introduces the introduced fuel into the pump unit 30. to provide.

In the process of performing the fuel pumping operation, some of the fuel in the chamber chamber 13 ′ is heated by heat generated when the motor of the motor unit 20 is driven to evaporate from the liquid state to the gas state, thereby changing the state.

Thus, as shown in FIG. 5A, a gaseous fuel layer, that is, a gas phase layer B, is formed on the liquid fuel layer, that is, the liquid phase layer A, as shown in FIG. 5A. As it passes, the gas phase layer B gradually expands, and the oil surface C between the liquid phase layer A and the gas phase layer B gradually descends downward.

At this time, since the external fuel pump 10 according to the present invention includes a gaseous inlet 35a and the liquid inlet 35b to 35e together, the oil surface C is higher than the gaseous inlet 35a as shown in FIG. 5A. When the steady state is maintained, the liquid fuel is sucked into the engine 5 through the gas phase inlet 35a and the liquid inlet 35b to 35e.

However, as the gas phase is enlarged, as shown in FIG. 5B, when the oil level C is lowered below the lower end of the gas inlet 35a, when the vehicle runs on a slope or corners, as shown in FIG. 5C. When the vehicle is inclined or vibrates while driving, the height of the oil surface C changes as the fuel slumps, as shown in FIG. 5D.

Therefore, when the oil level C is in an abnormal state lower than the gas phase inlet 35a, the gas phase inlet 35a inhales gaseous fuel, and the liquid inlets 35b through 35e inhale liquid fuel. Supplies).

On the other hand, the gaseous fuel sucked into the chamber 30a through the gaseous phase inlet 35a and the first check valve 33 is compressed by the pumping pressure PP of the diaphragm 32 and then changed back into the liquid state. Is discharged through the second check valve 34 and supplied to the engine 5. Therefore, since the engine 5 is supplied with only liquid fuel, it is not necessary for the electronic control unit (not shown) of the vehicle to perform a separate control operation for changing the mixing ratio or changing the amount of intake fuel. none.

In addition, since the external fuel pump 10 according to the present invention reduces the gas phase by sucking the gaseous fuel in accordance with the change in the height of the fuel oil level, the oil level C can be prevented from being lowered continuously.

As a result, the external fuel pump 10 according to the present invention can smoothly supply fuel to the engine 5 to prevent the engine 5 embossment, and in particular, the start of the engine 5 is stopped by reducing the fuel shortage phenomenon. Possible causes can be eliminated beforehand to prevent traffic accidents.

Next, the external fuel pump according to the second embodiment of the present invention will be described in detail with reference to FIG. 6.

6 is a cross-sectional view of an external fuel pump according to a second embodiment of the present invention.

As shown in FIG. 6, the external fuel pump 10 according to the second embodiment of the present invention includes a motor unit 20 for rotating a shaft 23 having an eccentric drive unit 24 formed thereon to pump fuel, The pump unit 30 for pumping fuel by using the rotational movement of the eccentric drive unit 24 and the outside of the pump unit 30 are shielded, and the fuel supplied from the cylinder 2 is housed in the chamber chamber 13 '. It comprises a pump chamber 13 is formed with a fuel inlet 14 to be introduced into.

The external fuel pump 10 according to the second embodiment of the present invention has a skeleton formed by the pump body 11, the motor portion 20 is installed in the upper portion of the pump body 11, the pump portion in the lower portion 30 is installed.

The upper side of the pump body 11 is coupled to the cover 12 for shielding the outside of the motor unit 20, the lower side is coupled to the pump chamber 13 for shielding the outside of the pump unit 30.

The pump chamber 13 is formed in a cylindrical shape having one side opened, and has a fuel inlet 15 connected to a fuel supply line S so as to introduce fuel supplied from the bomber 2 on the lower surface thereof.

The fuel inlet 15 is preferably formed in the center of the lower surface of the pump chamber (13).

The motor unit 20 is installed on the motor cover 21 and the pump body 11 to shield the outside to provide power to pump fuel (Brushless Direct Current Motor, hereinafter referred to as a motor) ) And a shaft 23 coupled to the inside of the motor 22 and having an eccentric drive unit 24 at the bottom thereof.

As shown in FIG. 4, the pump unit 30 includes five chambers 30a to 30e arranged at predetermined angles to pump fuel.

The number of the chambers 30a to 30e is not necessarily limited thereto, and may be variously changed to two or more according to conditions such as the size, pumping capacity, pumping speed, and pumping pressure of the external fuel pump 10. .

Each of the five chambers 30a to 30e has a plunger 31 for converting the rotational movement of the eccentric drive unit 24 into a linear reciprocating motion, and the linear reciprocating motion of the plunger 31. The diaphragm 32 for pumping the fuel introduced into the chamber chamber 13 'through the fuel inlet 14 of the pump chamber 13, and the diaphragm 32 is operated by pumping pressure. 13 ') first and second check valves 33 and 34 for sucking and discharging fuel therein and an inlet 35 through which fuel is sucked into the first check valve 33 from the chamber chamber 13'. Equipped.

As shown in FIG. 4, since the inlets 35 are provided for each of the chambers 30a to 30e, a total of five inlets are provided, one of which is a gaseous inlet for inhaling gaseous fuel. The four 35b to 35e are liquid intake ports for sucking liquid fuel.

The gas phase suction ports 35a and the liquid phase suction ports 35b to 35e are formed to have different heights.

In the present embodiment, the gas phase suction port 35a is formed to have the same height as the conventional suction port, and each of the liquid suction ports 35b to 35e lowers the suction position of the fuel even if the height of the fuel oil level is changed, thereby allowing the fuel to be in the liquid state. It is connected to the hose 36 extending in a predetermined length toward the lower surface of the pump chamber 13 so as to smoothly suck.

At this time, the length of the hose 36 is determined according to the experimental results of measuring the height of the fuel oil surface during the fuel pumping operation to suck the liquid fuel in the lower portion of the liquid layer.

As such, the external fuel pump 10 according to the present invention is connected to a gas inlet 35a for sucking gaseous fuel and a hose 36 having a predetermined length, and thus, a liquid inlet 35b for sucking liquid fuel. 35e), it is possible to selectively suck the liquid fuel and the gas fuel in accordance with the change in the height of the fuel oil level.

Hereinafter, the operation of the external fuel pump according to the second embodiment of the present invention will be described in detail with reference to FIGS. 7A to 7B.

7A and 7B are operation state diagrams of an external fuel pump according to a second embodiment of the present invention.

When the ignition key (not shown) of the vehicle is turned on and the battery power is supplied, the motor unit 20 of the external fuel pump 10 starts driving.

That is, as the motor 22 rotates, the shaft 23 rotates. Then, the plunger 31 provided in contact with the eccentric drive part 24 provided in the lower part of the shaft 23 converts the rotational motion of the eccentric drive part 24 into linear reciprocating motion.

In addition, the diaphragm 32 opens and closes the first and second check valves 33 and 34 by pumping according to the linear reciprocating motion of the plunger 31.

On the other hand, as the multi-valve 3 is opened by receiving battery power, fuel stored in the cylinder 2 is supplied to the external fuel pump 10.

Accordingly, the external fuel pump 10 introduces fuel into the chamber chamber 13 ′ through the fuel inlet 15 formed in the lower surface of the pump chamber 13, and provides the introduced fuel to the pump unit 30. do.

In the process of performing the fuel pumping operation, some of the fuel in the chamber chamber 13 ′ is heated by heat generated when the motor of the motor unit 20 is driven to evaporate from the liquid state to the gas state, thereby changing the state.

Therefore, in the chamber chamber 13 ′, as shown in FIG. 7A, a gaseous fuel layer, that is, a gas phase layer B, is formed on the upper portion of the liquid fuel layer, that is, the liquid layer A. As it passes, the gas phase layer B gradually expands, and the oil surface C between the liquid phase layer A and the gas phase layer B gradually descends downward.

At this time, the external fuel pump 10 according to the second embodiment of the present invention, as shown in Figure 7b, as the fuel inlet 15 is installed on the lower surface of the pump chamber 13 fuel from the cylinder 2 By the supplied supply pressure SP and the pumping pressure PP of the pump unit 30, the height of the oil surface C may be maintained higher than the lower end of the pump unit 30, that is, the lower end of the first check valve 33. have.

As a result, the fuel inlet 14 provided on the lower surface of the pump chamber 13 can continuously supply the liquid fuel into the chamber chamber 13 ′ without passing through the gas phase layer B, and thus, the pump chamber according to the prior art. The fuel can be smoothly supplied as compared to the fuel pump 4 in which the fuel inlet 4b is formed at the upper end side of the side 4a.

Accordingly, since the external fuel pump 10 according to the present invention includes the gaseous inlet 35a and the liquid inlet 35b to 35e together, the oil surface C is more than the gaseous inlet 35a as shown in FIG. 5A. When maintaining a high steady state, the liquid fuel is sucked into the engine 5 through the gas phase intake port 35a and the liquid intakes 35b to 35e.

On the other hand, when the vehicle body is inclined during driving or cornering as shown in FIG. 7C, when the vehicle body is inclined or vibrates while the vehicle is running, the fuel is raised as the height of the oil surface C as shown in FIG. 7D. Will change.

Therefore, when the oil level C is in an abnormal state lower than the gas phase inlet 35a, the gas phase inlet 35a inhales gaseous fuel, and the liquid inlets 35b through 35e inhale liquid fuel and the engine 5 Supplies).

On the other hand, the gaseous fuel sucked into the chamber 30a through the gaseous phase inlet 35a and the first check valve 33 is compressed to the pumping pressure of the diaphragm 32 and then changed back into the liquid state. It is discharged through the valve 34 and supplied to the engine 5. Therefore, since the engine 5 is supplied with only liquid fuel, it is not necessary for the electronic control unit (not shown) of the vehicle to perform a separate control operation for changing the mixing ratio or changing the amount of intake fuel. none.

In addition, since the external fuel pump 10 according to the present invention reduces the gas phase by sucking the gaseous fuel in accordance with the change in the height of the fuel oil level, the oil level C can be prevented from being lowered continuously.

As a result, the external fuel pump 10 according to the present invention can smoothly supply fuel to the engine 5 to prevent the engine 5 embossment, and in particular, the start of the engine 5 is stopped by reducing the fuel shortage phenomenon. Possible causes can be eliminated beforehand to prevent traffic accidents.

Next, an external fuel pump according to a third embodiment of the present invention will be described in detail with reference to FIG. 8. 8 is a perspective view illustrating a chamber of an external fuel pump according to a third embodiment of the present invention.

The configuration of the external fuel pump 10 according to the present embodiment is similar to that of the second embodiment, except that the configuration of the chamber is different.

In detail, in the present embodiment, the external fuel pump includes gaseous gas inlets 35a and 35c in two chambers 30a and 30c of the five chambers 30a to 30e, as shown in FIG. 8. Liquid chamber suction ports 35b, 35d, and 35e are provided in the three chambers 30b, 30d, and 30e.

At this time, the gaseous inlet (35a, 35c) and the liquid inlet (35b, 35d, 35e) may be provided so that the intake port of each group is adjacent to each other, so as to smoothly discharge the gaseous fuel during fuel flow in FIG. It is preferred that they are formed alternately with each other as shown.

As described above, the present invention may change the number of chambers to two or more, and change the number and positions of the gaseous inlet port and the liquid inlet port provided in each chamber in various ways.

For example, in the case of having seven chambers, the invention may be modified to have three gas phase inlets and four liquid phase inlets.

Through the above process, the present invention can smoothly supply fuel to the engine by selectively sucking the liquid and gaseous fuel through the liquid inlet and the gaseous inlet.

The scope of the present invention is not limited to the embodiments described above, but is defined by the claims, and various changes and modifications can be made by those skilled in the art within the scope of the claims. It is self evident.

The external pump of the present invention can be changed so that the height of the gas phase inlet is formed to be higher than that of the conventional inlet port so as to smoothly discharge the gaseous fuel.

In the second embodiment, the hoses 36 are connected to the liquid inlets 35b to 35e. However, the chambers 30a to 30e provided in the pump chamber 11 are not provided with the hoses 36, respectively. At the time of initial molding, the height of the liquid inlets 35b to 35e may be shaped to correspond to the length of the hose 36.

1 is a configuration of a gas vehicle lpai system according to the prior art.

2 is a cross-sectional view of the fuel pump shown in FIG.

3 is a cross-sectional view of an external fuel pump according to a first embodiment of the present invention.

4 is a perspective view showing a chamber of the external fuel pump shown in FIG.

5a to 5d is an operational state diagram of the external fuel pump according to the first embodiment of the present invention.

6 is a cross-sectional view of an external fuel pump according to a second embodiment of the present invention.

7a to 7d is an operational state diagram of an external fuel pump according to a second embodiment of the present invention.

8 is a perspective view showing a chamber of an external fuel pump according to a third embodiment of the present invention.

`` Explanation of symbols for main parts of drawings ''

10: External fuel pump 13: Pump chamber

13 ': chamber 14,15: fuel inlet

20: motor portion 30: pump portion

31: Plunger 32: Diaphragm

33, 34: check valve 35: inlet

36: hose

Claims (8)

Motor unit 20 for rotating the shaft 23, the eccentric drive unit 24 is formed at the bottom to pump the fuel supplied from the cylinder 2, Pump unit 30 for pumping fuel by using the rotational movement of the eccentric drive unit 24 and And a pump chamber 13 formed with a fuel inlet 14 for shielding the outside of the pump unit 30 and introducing fuel supplied from the cylinder 2 into the chamber chamber 13 '. The pump unit 30 includes a plurality of chambers, some of which include a gaseous inlet 35a for sucking gaseous fuel from the chamber chamber 13 ', and the rest of the chambers provide liquid fuel. External fuel pump comprising a liquid suction port (35b to 35e) to suck. The liquid intake port (35b to 35e) of claim 1 External fuel pump, characterized in that connected to the hose (35) extending to a predetermined length toward the lower surface of the pump chamber (13) to lower the suction position of the fuel introduced into the chamber chamber (13 '). The liquid intake port (35b to 35e) of claim 1 External fuel pump, characterized in that extending to the lower surface of the pump chamber (13) to lower the suction position of the fuel introduced into the chamber chamber (13 ') during the initial molding. 4. The gas phase suction port 35a according to claim 2 or 3, An external type which sucks the liquid fuel when the fuel oil surface C between the liquid fuel A and the gaseous fuel B is higher than the lower end of the gas phase suction port 35a. Fuel pump. 5. The gas phase inlet (35a) according to claim 4, The external fuel pump, characterized in that for sucking the gaseous fuel when the fuel oil surface (C) is lower than the gas phase suction port (35a). 6. The gas phase inlet (35a) according to claim 5, At least one or more, when provided with a plurality (35a, 35c) is provided adjacent to each other or the external fuel pump, characterized in that alternately provided with the liquid inlet (35b, 35d, 35e). 7. The fuel inlet of claim 6, wherein the fuel inlets 35b to 35e are External fuel pump, characterized in that formed on the upper side of the pump chamber (13). 7. The fuel inlet of claim 6, wherein the fuel inlets 35b to 35e are External fuel pump, characterized in that formed on the lower surface of the pump chamber (13).

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