KR20010023220A - Fuel Reservoir - Google Patents

Abstract

A fuel storage device for storing fuel divides an internal space of a fuel storage device into a fuel chamber and an air chamber, and divides the shape into a partition wall that is deformed depending on the amount of fuel in the fuel chamber, and a space formed above the fuel interface in the fuel chamber. An open discharge passage and a shutoff valve blocking the discharge passage. When the shutoff valve is opened, gas is discharged from the space through the discharge passage. When the amount of gas is greater than the predetermined amount, the shutoff valve is opened to discharge gas from the space. On the other hand, when the amount of gas is less than the predetermined amount, the shutoff valve is closed to stop the discharge of the gas.

Description

Fuel Storage Device {Fuel Reservoir}

The fuel storage device or fuel tank must communicate with the atmosphere so that the interface of the fuel can rise and fall within the fuel tank. In the fuel tank, evaporated fuel is generated in a space formed above the fuel interface. Thus, a problem arises in that evaporated fuel is released from the fuel tank to the atmosphere.

Conventionally, fuel tanks are in communication with the atmosphere via a charcoal canister that temporarily adsorbs evaporated fuel. If the amount of evaporated fuel generated in the fuel tank is large, the charcoal canister must be made large. In order to solve this problem, Japanese Patent Application Laid-Open No. 64-16426 includes a fuel having an air inflatable airbag that expands or contracts in accordance with a change in the level of the fuel interface to prevent the formation of a space above the interface of the fuel in the fuel tank. A tank is disclosed.

However, in the fuel tank disclosed in the patent, the inside of the fuel tank is not in communication with the atmosphere. Therefore, if the space has already been formed above the fuel interface, it cannot be excluded when the airbag is inflated. Thus, evaporative fuel can be generated in the space above the fuel interface.

It is therefore an object of the present invention to exclude the space above the fuel interface and the evaporated fuel therein from the fuel storage device.

The present invention relates to a fuel storage device, and more particularly to a fuel tank connected to an engine.

1 is a cross-sectional view of a fuel storage device according to a first embodiment of the present invention.

2 is a cross-sectional view of the fuel storage device along line II-II of FIG. 1.

3 is a cross-sectional view of the fuel storage device immediately after the supply of fuel into the fuel chamber is stopped.

4 is a cross-sectional view of the fuel storage device when the fuel in the fuel chamber is reduced.

5 is a cross-sectional view of a fuel storage device according to a second embodiment of the present invention.

6 is a flow chart of the evaporative fuel discharge action according to the second embodiment of the present invention.

7 is a cross-sectional view of a fuel storage device according to a third embodiment of the present invention.

8 is a flow chart of the evaporative fuel discharge action according to the third embodiment of the present invention.

9 is a sectional view of a fuel storage device according to a fourth embodiment of the present invention.

10 is a flow chart of the evaporative fuel discharge action according to the fourth embodiment of the present invention.

11 is a cross-sectional view of a fuel storage device according to a fifth embodiment of the present invention.

12 is a flowchart of the evaporative fuel discharge action according to the fifth embodiment of the present invention.

13 is a cross-sectional view of a fuel storage device according to a sixth embodiment of the present invention.

14 is a sectional view of a fuel storage device according to a seventh embodiment of the present invention.

15 is a flow chart of the evaporative fuel discharge action according to the seventh embodiment of the present invention.

16 is a cross-sectional view of a fuel storage device according to an eighth embodiment of the invention.

17 is a flowchart of the evaporative fuel discharge action according to the eighth embodiment of the present invention.

18 is a sectional view of a fuel storage device according to a ninth embodiment of the present invention;

19 is a flow chart of the evaporative fuel discharge action according to the ninth embodiment of the present invention.

20 is a cross-sectional view of a fuel storage device according to a tenth embodiment of the present invention.

21 is a flowchart of the evaporative fuel discharge action according to the tenth embodiment of the present invention.

22 is a flow chart of the evaporative fuel discharge action according to the tenth embodiment of the present invention.

23 is a sectional view of a fuel storage device according to an eleventh embodiment of the invention.

24 is a sectional view of a fuel storage device according to a twelfth embodiment of the invention;

25 is a sectional view of a fuel storage device according to a thirteenth embodiment of the present invention;

Fig. 26 is a flowchart of the evaporative fuel discharge action according to the thirteenth embodiment of the present invention.

27 is a flowchart of the evaporative fuel discharge action according to the thirteenth embodiment of the present invention.

28 is a partial cross-sectional view of a fuel storage device according to a fourteenth embodiment of the present invention.

29 is a perspective view of a fuel storage device according to a fourteenth embodiment of the present invention.

30 is a perspective view of a fuel storage device in an expanded state;

31 is a perspective view of a fuel storage device in a retracted state;

32 is a partial cross-sectional view of a fuel pump device according to a fourteenth embodiment of the present invention.

33 is a partial cross-sectional view of the fuel pump device along line XXXIII-XXXIII in FIG. 32.

34 is a partial sectional view of another fuel pump device different from the device according to the fourteenth embodiment of the present invention.

35 is a partial sectional view of a fuel pump device according to a fifteenth embodiment of the present invention;

36 is a partial cross-sectional view of the fuel pump device along line XXXVI-XXXVI in FIG. 35.

According to the present invention, a fuel storage device for storing fuel includes a partition wall that divides the inside of the device into a fuel chamber and an air chamber and is deformable according to the amount of fuel in the fuel chamber, and an upper portion of an interface of the fuel in the fuel chamber. A discharge passage open to the space, a shutoff valve for blocking the discharge passage, gas discharge means for discharging gas from the space via the discharge passage when the shutoff valve is opened, and when the amount of gas is greater than a predetermined amount The shutoff valve is opened for discharging gas from the space and has control means for controlling the gas discharge means and the shutoff valve such that the gas discharge means is operated, the control means having a gas when the amount of gas is less than Closing the shutoff valve to stop the discharging action of the gas It stops the operation.

Further, according to the present invention, there is provided a fuel interface level detecting means for detecting the level of the interface of the fuel in the fuel chamber, wherein the control means is such that the level of the interface of the fuel detected by the fuel interface level detecting means is lower than the predetermined level. When the amount of gas is determined to be larger than the expected amount.

According to the present invention, there is also provided a fuel interface level raising means for raising the level of the interface of the fuel, wherein the gas discharge means raises the level of the interface of the fuel to discharge gas from the space when the amount of gas is greater than the predetermined amount. Control means for raising the fuel interface level.

Further, according to the present invention, the fuel interface level raising means supplies fuel to the fuel chamber to raise the level of the interface of the fuel.

Further, according to the present invention, the fuel interface level raising means deforms the dividing wall to raise the level of the interface of the fuel.

In addition, according to the present invention, the fuel interface level raising means increases the pressure in the air chamber to deform the dividing wall.

Further, according to the present invention, the fuel interface level raising means increases the pressure in the air chamber to a pressure lower than the pressure of the fuel supplied to the fuel chamber when the supply of fuel to the fuel chamber is stopped.

Further, according to the present invention, the fuel interface level raising means reduces the pressure in the air chamber when the supply of fuel to the fuel chamber is stopped.

Further, according to the present invention, the fuel interface level raising means introduces a negative pressure into the space so as to deform the partition wall.

Further, according to the present invention, the fuel interface level raising means has a fuel pump for pumping fuel to generate underpressure by the pumped fuel, and introduces the underpressure into the space via the discharge passage.

Further, according to the present invention, the fuel interface level raising means returns a part of the fuel pumped by the fuel pump into the fuel chamber to generate underpressure.

Furthermore, according to the invention, the fuel pump is mounted in a pump chamber connected to the fuel chamber, and the fuel interface level raising means returns a part of the fuel pumped by the fuel pump into the pump chamber to generate underpressure, and in the pump chamber A negative pressure is introduced into the space formed above the interface of the fuel.

Further, according to the present invention, the discharge passage is connected to the intake system of the engine, and the fuel interface level raising means introduces the negative pressure in the intake system into the space formed above the interface of the fuel via the discharge passage.

In addition, according to the invention, the discharge passage is connected to the intake system via the canister to adsorb evaporated fuel, the canister having a valve that opens to the atmosphere to communicate the canister with the atmosphere when the pressure in the canister is lower than the predetermined pressure. Equipped.

Further, according to the present invention, the fuel interface level raising means raises the level of the interface of the fuel when the engine can accommodate the evaporated fuel.

The invention will be more clearly understood from the description of a suitable embodiment of the invention described below in conjunction with the accompanying drawings.

A fuel storage device according to a first embodiment of the present invention will be described below. For example, a fuel storage device is mounted to a vehicle for storing fuel to be supplied to an engine. In contrast, a fuel storage device may be used to store fuel for a predetermined period of time.

As shown in FIG. 1, the fuel tank 1 of the fuel storage device has an upper portion 2 and a lower portion 3 made of a material such as metal or synthetic resin. The upper part 2 and the lower part 3 are hermetically connected to each other at their peripheral flanges 2a, 3a.

The dividing wall 5 or sheet is disposed in the interior space 4 formed by the upper part 2 and the lower part 3. The separating wall 5 separates the internal space 4 into an air chamber 6 located above the separating wall 5 and a fuel chamber 7 located below the separating wall 5. The partition wall 5 is formed of a material having flexibility and vapor impermeability, such as polyethylene or nylon. The separating wall 5 is fixed to the fixing part 8 at its periphery 5a. In other words, the separating wall 5 is hermetically fixed to the inner wall surface of the fuel tank 1. The peripheral portion 5a of the separating wall 5 is fixed between the upper portion 2 and the peripheral flange portions 2a, 3a of the lower portion 3.

The separating wall 5 is generally provided concentrically and annular bent portions 5b spaced at equal intervals from each other. Thus, the separating wall 5 has a corrugated portion formed by the annular bent portion 5b. The partition wall 5 may be curved at the bent portion 5b. Thus, the central portion 5c of the separating wall 5 can be moved up and down in the fuel tank 1. Thus, the separating wall 5 is deformed at the bent portion 5b so that the center portion 5c is moved up and down.

The fuel supply pipe 13 is hermetically connected to the lower part 3 and opens into the fuel chamber 7. A cap 14 for closing the fuel supply pipe 13 is removably fixed to the upper opening 13a of the fuel supply pipe 13. A nozzle is inserted into the fuel supply pipe 13 to fill the fuel chamber 7 with the sealing member 15 which is in contact with the outer circumferential surface of the cap 14 when the cap 14 is fixed to the opening 13a. The fuel supply pipe 13 adjacent to the opening 13a is a sealing member 16 which is in contact with the outer circumferential surface of the fuel filling nozzle and an evaporative fuel shutoff valve 17 which blocks the fuel supply pipe 13 by a spring force. Is provided within.

On the other hand, a check valve 10 is provided in the lower opening 13b of the fuel supply pipe 13. The check valve 10 is opened by the pressure of the fuel supplied from the fuel filling nozzle and closed by the pressure of the fuel in the fuel chamber 7.

The fuel pump chamber 18 is connected to the fuel chamber 7. The fuel pump chamber 18 is formed by the lower portion 3 and protrudes outward from the peripheral flange portion 2a of the upper portion 2.

The fuel pump 19, the pressure regulator 20, and the fuel filter 21 are disposed in the fuel pump chamber 18. The pressure of the fuel pumped by the fuel pump 19 is regulated by the pressure regulator 20, after which the fuel is supplied to a fuel injector (not shown) via the fuel supply pipe 22. There is no need for any fuel return passage to return fuel from the fuel distribution pipe to the fuel tank 1 for dispensing fuel from the fuel supply pipe 22 to each injector, which means that the pressure regulator 20 has a fuel chamber 7 This is because the fuel is returned to the fuel pump chamber 18 connected to the. Thus, the fuel heated near the cylinder head of the engine and containing the evaporated fuel is not returned into the fuel chamber 7. Thus, generation of evaporated fuel in the fuel chamber 7 is prevented. Moreover, since the fuel pump 19 is located in the fuel tank 1, transmission of noise of the fuel pump 19 from the fuel tank 1 to the outside of the fuel tank 1 is prevented.

The fuel chamber 7 is connected to the fuel supply pipe 13 via the circulation pipe 23. The circulation pipe 23 is connected to the lower part 3 and opens into the fuel chamber 7 above the lower opening 13b of the fuel supply pipe 13 and directly under the fixing part 8. The circulation pipe 23 releases air from the fuel chamber 7 to the fuel supply pipe 13 when fuel is supplied into the fuel chamber 7 via the fuel supply pipe 13. Thus, the supply of fuel into the fuel chamber 7 is easily performed.

The first shut-off valve 30 is attached to the opening of the circulation pipe 23 which is opened into the fuel chamber 7. The first shut-off valve 30 is closed by the fuel that reaches it. Thus, when the first shut-off valve 30 is closed, the pressure in the fuel supply pipe 13 adjacent to the opening of the circulation pipe 23 opened into the fuel supply pipe 13 is reduced.

The upper space 18a in the fuel pump chamber 18 communicates with the interior of the fuel supply pipe 13 via the evaporative fuel discharge pipe 24. The evaporative fuel discharge pipe 24 is connected to the upper wall portion that forms the fuel pump chamber 18. The evaporative fuel discharge pipe 24 releases air from the fuel chamber 7 to the fuel supply pipe 13 when fuel is supplied into the fuel chamber 7 via the fuel supply pipe 13. Thus, the supply of fuel into the fuel chamber 7 is easily performed.

The second shut-off valve 31 is attached to the opening of the evaporative fuel discharge pipe 24 that is opened into the fuel pump chamber 18. The second shut-off valve 31 is closed by the fuel that reaches it. Thus, when the second shutoff valve 31 is closed, the pressure in the fuel supply pipe 13 adjacent to the opening of the evaporative fuel discharge pipe 24 opened into the fuel supply pipe 13 is reduced. The opening of the evaporative fuel discharge pipe 24 opened into the fuel supply pipe 13 is located above the opening of the circulation pipe 23 opened into the fuel supply pipe 13.

The fuel supply pipe 13 is connected to the charcoal canister 26 via a first evaporative fuel purging pipe 25. The opening of the first evaporated fuel purge pipe 25 opened into the fuel supply pipe 13 is located at the same height as the opening of the evaporated fuel discharge pipe 24 opened into the fuel supply pipe 13.

Charcoal canister 26 is provided with activated carbon 26a for adsorbing evaporative fuel. Charcoal canister 26 is opened to the atmosphere via atmospheric open pipe 28. Charcoal canister 26 is also connected to an intake passage (not shown) of the engine via second evaporative fuel purge pipe 27.

The evaporated fuel generated in the fuel chamber 7, the fuel supply pipe 13, and the fuel pump chamber 18 includes a circulation pipe 23, an evaporated fuel discharge pipe 24, and a first evaporated fuel purge pipe ( It is introduced into charcoal canister 26 via 25 and adsorbed to activated carbon 26a. Thus, the discharge of the evaporated fuel to the atmosphere is prevented. The evaporated fuel adsorbed to the activated carbon 26a is purged into the intake passage via the second evaporated fuel purge pipe 27 based on the engine driving state such as the engine load.

For example, when the vehicle with the fuel tank rotates, the separating wall 5 is moved by the movement of the fuel in the fuel chamber 7. Therefore, a large load such as stress occurs in the separating wall 5. In the first embodiment, as shown in FIG. 2, the inner wall surface of the side wall 3b of the lower part 3 is inclined inward from the fixing part 8 to the lower wall 3c of the lower part 3. . When the central portion 5c is located in the lower region in the fuel chamber 7, the shape of the inner wall surface of the side wall 3b corresponds to the shape of the corrugation portion formed by the bent portion 5b. Thus, horizontal and vertical movement of the corrugated portion of the separating wall 5 and movement of the separating wall 5 are prevented regardless of the position of the central portion 5c of the separating wall 5 in the fuel chamber 7.

An annular projection 29 is formed on the inner wall surface of the side wall 3b of the lower portion 3. Since the protrusion 29 protrudes inward from the side wall 3b, the side wall 3b has a stepped portion. The corrugated portion including the bent portion 5b is in flexible contact with the protrusion. Therefore, horizontal and vertical movement of the corrugated portion of the separation wall 5 and movement of the separation wall 5 are prevented.

Since the protrusions 29 are formed on the side wall 3b from the fixing portion 8 to the lower wall 3c, recesses are formed between the adjacent protrusions 29. Since the recess supports the bent portion 5b, the horizontal and vertical movement of the corrugated portion of the separating wall 5 and the movement of the separating wall 5 are further prevented.

As described above, generation of large stresses in the separating wall 5 is prevented, so that breakage of the separating wall 5 is prevented.

Further, since the protrusion 29 reduces the air volume formed between the fuel interface and the separating wall 5, the amount of evaporated fuel generated in the fuel chamber 7 is reduced. Further, since the protrusion 29 reinforces the lower portion 3, no reinforcing member for reinforcing the lower portion 3 need be provided.

A spring 32 as a deflection or elastic means is attached to the inner wall surface of the upper part 2 of the fuel tank 1. The spring 32 extends downwardly from the inner wall surface of the upper part 2. The spring 32 is supported by the central portion 5c of the separating wall 5 when the central portion 5c is raised. Thus, the collision of the separating wall 5 against the inner wall surface of the upper part 2 is prevented.

The air chamber 6 communicates with the atmosphere via an atmospheric communication pipe 33 that is open to the atmosphere. The atmospheric communication pipe 33 is connected to the upper part 2 of the fuel tank 1. The atmospheric communication pipe 33 releases air from the air chamber 6 into the atmosphere when the center portion 5c of the separation wall 5 rises. Thus, the center portion 5c is easily raised when fuel is supplied into the fuel chamber 7. On the other hand, the atmospheric communication pipe 33 introduces air from the atmosphere into the air chamber 6 when the central portion 5c of the separating wall 5 descends. Therefore, the center portion 5c is easily lowered when the fuel in the fuel chamber 7 is used during the driving of the engine.

According to the first embodiment of the present invention, the action of discharging evaporated fuel from the space above the fuel interface in the fuel chamber 7, ie, the space between the fuel interface and the separating wall 5 in the fuel chamber (hereinafter referred to as “evaporation fuel discharge”). Action ") will be described below.

In the first embodiment, fuel is supplied to the fuel chamber 7 when there is a space above the fuel interface in the fuel chamber 7. The level of the fuel interface is raised by the supply of fuel into the fuel chamber 7. Thus, the evaporated fuel in the space above the fuel interface is discharged therefrom to the fuel supply pipe 13 via the circulation pipe 23 and the evaporative fuel discharge pipe 24.

When the fuel interface reaches the first and second shut-off valves 30 and 31, ie when the evaporated fuel in the space above the fuel interface is completely discharged, the fuel chamber 7 is sealed. Then, fuel is stopped supplied into the fuel chamber 7. When the fuel chamber 7 is sealed, the sealing of the fuel chamber 7 is maintained, so that no space is formed above the fuel interface in the fuel chamber 7. Thus, generation of evaporated fuel in the fuel chamber 7 is prevented. In the first embodiment, the supply of fuel into the fuel chamber 7 corresponds to means for discharging gas from the space formed above the fuel interface or for raising the level of the fuel interface.

The evaporative fuel discharge action according to the first embodiment will be described below with reference to the drawings.

1 shows a fuel tank 1 containing evaporative fuel. Before the supply of fuel into the fuel chamber 7 is started, the cap 14 is removed from the upper opening 13a of the fuel supply pipe 13. When the cap 14 is removed, the evaporative fuel shutoff valve 17 is closed. Therefore, discharge of the evaporated fuel from the upper opening 13a to the atmosphere is prevented.

Next, a fuel filling nozzle (not shown) is inserted into the upper opening 13a of the fuel supply pipe 13. The nozzle opens the evaporative fuel shutoff valve 17 against the biasing force, and the outer circumferential surface of the next nozzle is in contact with the sealing member 16. Thus, when the nozzle is inserted into the fuel supply pipe 13, the discharge of the evaporated fuel from the upper opening 13a to the atmosphere is prevented.

Next, fuel is supplied from the nozzle into the fuel chamber 7 via the fuel supply pipe 13. The level of the fuel interface in the fuel chamber 7 rises as the amount of fuel in the fuel chamber 7 increases. Thus, the dividing wall 5 is raised.

When the level of the fuel interface is raised, the evaporated fuel in the space above the fuel interface is discharged from the fuel chamber 7 via the circulation pipe 23 and the evaporative fuel discharge pipe 24. When the fuel interface is raised, the dividing wall 5 maintains hermetic contact with the fuel interface. Therefore, the amount of evaporated fuel generated in the fuel chamber 7 when the fuel is supplied to the inside is kept in a small amount.

When the fuel interface reaches the first shutoff valve 30, the first shutoff valve 30 is closed by the fuel in the fuel chamber 7 to shut off the circulation pipe 23. Thereafter, the upward movement of the central portion 5c of the separating wall 5 is limited by the spring 32. Then, as shown in FIG. 3, when the fuel interface reaches the second shutoff valve 31, the second shutoff valve 31 shuts off the evaporative fuel discharge pipe 24 in the fuel chamber 7. Closed by fuel. Thus, the evaporated fuel in the space above the fuel interface is completely discharged from the fuel chamber 7 and the fuel tank 1.

When the first and second shut-off valves 30 and 31 are closed, the pressure in the fuel supply pipe 13 is reduced below the predetermined pressure. When the pressure sensor in the nozzle detects that the reduced pressure is lower than the predetermined pressure, the supply of fuel into the fuel chamber 7 is stopped. Next, the pressure in the fuel in the fuel chamber 7 is higher than the pressure of the fuel in the fuel supply pipe 13. Thus, the check valve 10 is closed by the fuel in the fuel chamber 7. Thus, the fuel chamber 7 is completely sealed and there is no evaporative fuel in the fuel chamber 7.

Then, the nozzle is discharged from the upper opening 13a of the fuel supply pipe 13, after which the evaporative fuel shutoff valve 17 is closed by the spring force. The cap 14 is also attached to the upper opening 13a of the fuel supply pipe 13.

The operation of the fuel tank while driving the engine according to the first embodiment of the present invention will be described below.

During the drive of the engine, the fuel amount in the fuel chamber 7 is reduced. Therefore, the level of the fuel interface in the fuel chamber 7 is lowered, and the center portion 5c of the separating wall 5 is lowered. As shown in FIG. 4, the dividing wall 5 projects downward into the fuel chamber 7. When the dividing wall 5 is lowered, since the fuel chamber 7 is sealed, no space is formed above the fuel interface. Thus, the evaporative fuel discharge action is performed, and generation of the evaporated fuel in the fuel chamber 7 is prevented. Thus, only a small charcoal canister is installed or not installed at all in the fuel storage device.

In the first embodiment, the first and second shut-off valves 30 and 31 can be opened when fuel is supplied into the fuel chamber 7. Thus, a space is formed above the fuel interface in the fuel chamber 7, and evaporative fuel can be generated even if the engine is driven. Therefore, according to the second embodiment of the present invention, the evaporated fuel is discharged by a method other than supplying fuel into the fuel chamber 7.

A fuel storage device according to a second embodiment of the present invention will be described below.

In the second embodiment, as shown in FIG. 5, instead of the atmospheric communication pipe 33 of the first embodiment, an air pump 35 is connected to the air chamber 6 via the first connecting pipe 34. The air pump 35 serves to increase the pressure in the air chamber 6.

The first connecting pipe 34 is connected to the relief valve 37 via the second connecting pipe 36. When the pressure in the air chamber 6 becomes higher than the predetermined pressure, the relief valve 37 opens to reduce the pressure in the air chamber 6. The predetermined pressure is set lower than the pressure damaging the dividing wall 5.

Small holes 39 are formed in the diaphragm 38 of the relief valve 37. The hole 39 communicates the second connecting pipe 36 with the atmosphere regardless of the opening and closing of the relief valve 37. The diameter of the hole 39 is set such that an increase in the pressure in the air chamber 6 is not prevented by the air pump 35.

The level switch 57 is mounted on the upper wall of the fuel pump chamber 18 at the highest position in the fuel tank 1. When the fuel interface reaches the level switch 57, that is, when the fuel interface reaches the highest position in the fuel tank 1, the level switch 57 outputs a voltage.

The fuel storage device has an electronic control device 40. The control device 40 is a digital computer and includes a CPU (microprocessor) 42, a RAM (random access memory) 43, a ROM (read only memory) 44, and B interconnected by a bidirectional bus 41. RAM (backup RAM) 45, input port 46 and output port 47.

When the fuel interface reaches the level switch 57, the voltage generated in the level switch 57 is input to the input port 46 via the corresponding AD converter 48. The voltage indicating opening and closing of the relief valve 37 is input to the input port 46 via the corresponding AD converter 48. The output port 47 is connected to the air pump 35 via the drive circuit 49.

Parts other than the above-mentioned parts are the same as the parts of the fuel storage device which concerns on 1st Embodiment, and the description is abbreviate | omitted.

An evaporative fuel discharge operation according to the second embodiment will be described below.

In the second embodiment, it is determined whether the relief valve 37 is open. If the relief valve 37 is closed, it is determined that the pressure in the air chamber 6 allows the evaporative fuel discharge action.

Further, in the second embodiment, it is determined whether the level switch 57 is on. If the level switch 57 is in the off state, it is determined that the evaporative fuel discharge operation needs to be performed.

If the relief valve 37 is closed and it is determined that the level switch 57 is in the off state, the air pump 35 acts to increase the pressure in the air chamber 6. Thus, the central portion 5c of the separating wall 5 is lowered toward the lower wall 3c of the lower portion 3. Thus, the level of the fuel interface formed in the space above it is raised. When the level of the fuel interface is raised, the evaporated fuel is discharged from the fuel chamber 7 to the fuel supply pipe 13 via the circulation pipe 23 and the evaporative fuel discharge pipe 24.

If it is determined that the pressure in the air chamber 6 does not allow the evaporative fuel discharge action, the air pump 35 is stopped.

In the second embodiment, the air pump 35 corresponds to means for discharging gas from the space formed above the fuel interface or for raising the level of the fuel interface, and the level switch 57 is provided for the means for detecting the fuel interface. Corresponds.

An evaporative fuel discharge operation according to the second embodiment will be described below with reference to the flowchart of FIG. 6.

In step 210, it is determined whether the level switch 57 is on. If the level switch 57 is in the on state, it is determined that the evaporative fuel discharge action cannot be performed, and the routine proceeds to step 212 in which the air pump 35 is stopped, and the routine ends. On the other hand, if the level switch 57 is in the OFF state, it is determined that the evaporative fuel discharge operation can be executed, and the routine proceeds to step 214.

In step 214, it is determined whether the relief valve 37 is open. If the relief valve 37 is opened, it is determined that the evaporative fuel discharge action cannot be performed, the routine proceeds to step 212 in which the air pump 35 is stopped, and the routine ends. On the other hand, if the relief valve 37 is closed, it is determined that the evaporative fuel discharge action needs to be executed, and the routine pumps to increase the pressure in the air chamber 6 to discharge the evaporated fuel from the fuel chamber 7. Proceeds to step 216, where the routine is terminated.

In the first embodiment, in order to completely discharge the evaporated fuel from the fuel tank, it is necessary to fill the fuel tank with fuel until the fuel tank is completely filled with fuel. Therefore, if the supply of fuel into the fuel chamber 7 is stopped before the fuel tank is completely filled with fuel, the evaporated fuel cannot be discharged completely from the fuel chamber 7. In the third embodiment, even if the supply of fuel into the fuel chamber is stopped before the fuel chamber is completely filled with fuel, the evaporated fuel is completely discharged from the fuel chamber.

A fuel storage device according to a third embodiment of the present invention will be described below.

In the third embodiment, as shown in FIG. 7, the fuel tank 1 is provided with a cap cover opener switch 50. The opener switch 50 is connected to a cap cover (not shown) for covering the cap 14. The opener switch 50 outputs a voltage when the cap cover is opened and is operated to continue to output voltage until the cap is closed. Therefore, it is possible to determine whether fuel is supplied by detecting the voltage in the opener switch 50. The voltage generated in the opener switch 50 is input to the input port 46 via the corresponding AD converter 48.

Parts other than the above-mentioned parts are the same as the parts of the fuel storage device which concerns on 2nd Embodiment, and the description is abbreviate | omitted.

An evaporative fuel discharge operation according to the third embodiment will be described below.

In the third embodiment, it is determined whether the relief valve 37 is open. If the relief valve 37 is closed, it is determined that the pressure in the air chamber 6 allows the evaporative fuel discharge action.

In addition, it is determined whether the cap cover opener switch 50 is in the on state and the level switch 57 is in the off state. When the opener switch 50 is in the on state and the level switch 57 is in the off state, it is determined that the evaporative fuel discharge action needs to be performed.

If the pressure in the air chamber 6 is a pressure that does not allow the evaporative fuel ejection action, no evaporative fuel ejection action needs to be carried out, and the cap lid is opened to start the supply of fuel into the fuel chamber 7.

On the other hand, the pressure in the air chamber 6 is a pressure to allow the evaporative fuel discharge action, and if it is necessary to carry out the evaporative fuel discharge action, the air pump 35 is operated to increase the pressure in the air chamber 6. Thus, the central portion 5c of the dividing wall 5 is lowered. Thus, the evaporated fuel above the fuel interface is discharged from the fuel tank 1 to the fuel supply pipe 13 via the circulation pipe 23 and the evaporative fuel discharge pipe 24.

Then, if the pressure in the air chamber 6 is a pressure that does not allow the evaporative fuel ejection action, or if it is not necessary to carry out the evaporative fuel ejection action, the air pump is stopped and the cap to start supply of fuel into the fuel chamber 7. The cover is opened.

Thus, the air pump 35 corresponds to means for discharging gas from the space formed above the fuel interface or for raising the level of the fuel interface, and the level switch 57 corresponds to the means for detecting the level of the fuel interface. .

According to the third embodiment, when the supply of fuel into the fuel chamber 7 is started, the level of the fuel interface is raised to the highest level. Therefore, the amount of fuel to be supplied in order to raise the level of the fuel interface to the highest level in the fuel chamber 7 is smaller than in the first embodiment. Thus, according to the third embodiment, even if the supply of fuel into the fuel chamber 7 is stopped before the fuel chamber is completely filled with fuel, the evaporated fuel can be completely discharged from the fuel chamber 7.

Note that when the nozzle detects that the level of fuel in the fuel supply pipe 13 exceeds a predetermined level, the fuel supply nozzle used to supply fuel into the fuel chamber of the third embodiment stops the fuel supply. The predetermined level is set lower than the opening of the circulation pipe 23 which opens into the fuel supply pipe 13.

An evaporative fuel discharge operation according to the third embodiment will be described below with reference to the flowchart of FIG. 8.

In step 310, it is determined whether the cap cover opener switch 50 is in an on state. If the opener switch 50 is on, the routine proceeds to step 312. On the other hand, if the opener switch 50 is in the OFF state, the routine proceeds to step 318 in which the air pump 35 is stopped, and the routine ends.

In step 312, it is determined whether the level switch 57 is on. If the level switch 57 is in the on state, it is determined that no evaporative fuel discharge action is necessary, and the routine proceeds to step 314 in which the air pump 35 is stopped, and to step 316 in which the cap cover is opened, The routine is terminated. On the other hand, if the level switch 57 is off, the routine proceeds to step 320.

In step 320, it is determined whether the relief valve 37 is open. If the relief valve 37 is opened, it is determined that the evaporative fuel discharge action cannot be performed, the routine proceeds to step 314 where the air pump 35 is stopped, and to step 316 where the cap cover is opened, and the routine is It ends. On the other hand, if the relief valve 37 is closed, it is determined that the evaporative fuel discharge action can be performed, and the routine proceeds to step 322 where the air pump 35 is operated to increase the pressure in the air chamber 6, The routine is terminated.

In the second embodiment, an air pump 35 and a relief valve 37 are used to perform the evaporative fuel discharge action. Thus, the structure of the fuel storage device is complicated, and the cost of manufacturing the fuel storage device is increased. According to the fourth embodiment, the evaporative fuel discharge operation is performed with a simpler structure.

A fuel storage device according to a fourth embodiment will be described below.

In the fourth embodiment, as shown in FIG. 9, the fuel tank 1 is excluded, except for the air pump 35, the relief valve 37, the first and second connecting pipes 34, 36 of the second embodiment. Atmospheric communication pipes were connected to the upper part (2).

Instead of the charcoal canister 26 of the second embodiment, an electromagnetic valve 51 is connected to the first and second evaporative fuel purge pipes 25, 27. The fuel supply pipe 13 is connected to the intake passage 52 via the first and second evaporative fuel purge pipes 25, 27 and the electromagnetic valve 51. The electromagnetic valve 51 blocks the communication between the fuel supply pipe 13 and the intake passage 52.

The fuel storage device has a temperature sensor 55 for generating a voltage corresponding to the temperature of the coolant for engine cooling. The temperature sensor 55 is connected to the input port 46 via the corresponding AD converter 48. The output port 47 is connected to the electromagnetic valve 51 via the drive circuit 49.

Parts other than the above-mentioned parts are the same as the parts of the fuel storage device which concerns on 2nd Embodiment, and the description is abbreviate | omitted.

An evaporative fuel discharge operation according to the fourth embodiment will be described below.

In the fourth embodiment, it is determined whether the temperature of the cooling water is higher than the predetermined temperature (for example, 70 ° C). When the coolant cools the engine in normal operation, the predetermined temperature is higher than the coolant temperature. When the temperature of the coolant is higher than the predetermined temperature, the operating state of the engine allows the evaporative fuel discharge action.

Further, in the fourth embodiment, it is determined whether the level switch 57 is in the on state. If the level switch 57 is in the OFF state, it is determined that the evaporative fuel discharge operation needs to be performed.

The operating state of the engine allows the evaporative fuel discharge action, and when it is necessary to perform the evaporative fuel discharge action, the electromagnetic valve 51 is opened to introduce the negative pressure in the intake passage 52 into the fuel chamber 7. The introduced negative pressure discharges the evaporated fuel from the fuel chamber 7, lowers the central portion 5c of the separating wall 5, and raises the level of the fuel interface.

The electromagnetic valve 51 is closed when the operating state of the engine does not allow the evaporative fuel discharge action or does not need to perform the evaporative fuel discharge action.

Thus, according to the fourth embodiment, the fuel storage device having a simple structure without the air pump and the relief valve can discharge the evaporated fuel from the fuel chamber. In the fourth embodiment, the purge action of the evaporated fuel from the fuel chamber to the intake passage corresponds to means for discharging gas from the space formed above the fuel interface or for raising the level of the fuel interface, and the level switch 57 is a fuel Corresponds to the means for detecting the level of the interface.

Further, in the fourth embodiment, the evaporative fuel discharge action can be controlled based on the engine speed or the engine load, or the amount of air introduced into the combustion chamber of the engine, or the combustion conditions in the combustion chamber. For example, when the engine speed or engine load, or the amount of air introduced into the combustion chamber is lower than the predetermined amount, or when combustion is in a stratified condition, the evaporative fuel discharge action is stopped.

An evaporative fuel discharge operation according to the fourth embodiment will be described below with reference to the flowchart of FIG. 10.

In step 410, it is determined whether the level switch 57 is on. If the level switch 57 is in the on state, it is determined that no evaporative fuel discharge action needs to be performed, the routine proceeds to step 412 where the electromagnetic valve 51 is closed, and the routine ends. On the other hand, if the level switch 57 is off, the routine proceeds to step 414.

In step 414, it is determined whether the temperature T of the cooling water is higher than the predetermined temperature T0 (T> T0). If T> T0, it is determined that the operating state of the engine allows the evaporative fuel discharge action, the routine proceeds to step 416 in which the electromagnetic valve 51 is opened, and the routine ends. On the other hand, if T ≦ T0, it is determined that the operating state of the engine does not allow the evaporative fuel discharge action, the routine proceeds to step 412 in which the electromagnetic valve 51 is closed, and the routine is terminated.

In the fourth embodiment, when the charcoal canister needs to be provided in the fuel storage device, the charcoal canister is provided on the first evaporative fuel purge pipe 25 between the fuel supply pipe 13 and the electromagnetic valve 51. do. The charcoal canister may be in communication with the atmosphere to prevent excessive reduction of pressure in the canister when the electromagnetic valve 51 is opened and to prevent excessive increase in pressure in the fuel chamber 7 when the electromagnetic valve 51 is closed. have. Therefore, when the fuel storage device according to the fourth embodiment is provided with the charcoal canister, since the canister is in communication with the atmosphere, it is impossible to introduce negative pressure into the fuel chamber 7, so that the evaporated fuel in the fuel chamber 7 is discharged. It doesn't work. According to the fifth embodiment, the negative pressure can be introduced into the fuel chamber 7 even if the fuel storage device is provided with the charcoal canister.

A fuel storage device according to a fifth embodiment of the present invention will be described below.

In the fifth embodiment, as shown in FIG. 11, charcoal canister 26 is provided to the first evaporative fuel purge pipe 25 between the fuel supply pipe 13 and the electromagnetic valve 51. Charcoal canister 26 is in communication with the atmosphere via atmospheric open pipe 28.

A control valve 58 is provided in the atmospheric open pipe 28 to block the atmospheric open pipe 28. The control valve 58 consists of a positive pressure and a negative pressure valve. In addition, the control valve 58 opens at a constant pressure predetermined to reduce the pressure in the charcoal canister 26 and closes at a negative pressure predetermined to increase the pressure in the charcoal canister 26. The predetermined static pressure is such that the fuel tank 1, the charcoal canister 26, its associated components, and the pressure that the separation wall 5 can withstand, or that the evaporated fuel is the fuel tank 1, the charcoal canister 26 or It is lower than the pressure which does not come out of the part concerned The predetermined negative pressure is higher than the pressure that the fuel tank 1, the charcoal canister 26, its associated parts, and the separating wall 5 can withstand.

Parts other than the above-mentioned parts are the same as the parts of the fuel storage device which concerns on 4th Embodiment, and the description is abbreviate | omitted.

An evaporative fuel discharge operation according to the fifth embodiment will be described below.

In the fifth embodiment, it is determined whether the temperature of the cooling water is higher than the predetermined temperature. When the temperature of the cooling water is higher than the predetermined temperature, it is determined that the cooling water temperature allows the evaporative fuel discharge action. The predetermined temperature is higher than the temperature of the coolant when the coolant cools the engine in the normal operating state.

Further, in the fifth embodiment, it is determined whether the level switch 57 is in the on state. If the level switch 57 is in the OFF state, it is determined that the evaporative fuel discharge operation needs to be performed.

If it is determined that the temperature of the cooling water allows the evaporative fuel discharge action and it is necessary to perform the evaporative fuel discharge action, the electromagnetic valve 51 passes the negative pressure in the intake passage 52 via the second evaporative fuel purge pipe 27. Open to introduce into the charcoal canister 26. When negative pressure is introduced into the charcoal canister 26, due to the action of the control valve 58, the pressure in the charcoal canister 26 is lower than the predetermined static pressure and higher than the predetermined negative pressure. Of course, if the pressure in the charcoal canister 26 is lower than the predetermined negative pressure, the control valve 58 is opened, and a negative pressure lower than the predetermined negative pressure cannot be introduced into the fuel chamber 7, that is, only a negative pressure higher than the predetermined negative pressure is used. It can be introduced into the fuel chamber 7. Accordingly, the negative pressure in the intake passage 52 is introduced into the fuel chamber 7 via the first evaporative fuel purge pipe 25, the circulation pipe 23, and the evaporative fuel discharge pipe 24. Thus, according to the fifth embodiment, in the fuel tank with the charcoal canister, the negative pressure in the intake passage can be introduced into the fuel chamber 7 to discharge the evaporated fuel above the fuel interface.

In the fifth embodiment, the purge action of the evaporative fuel from the fuel chamber to the intake passage corresponds to means for discharging gas from the space formed above the fuel interface or for raising the level of the fuel interface, and the level switch 57 is a fuel Corresponds to the means for detecting the level of the interface.

If the temperature of the cooling water does not allow the evaporative fuel ejection action or does not need to perform the evaporative fuel ejection action, the electromagnetic valve 51 is closed.

An evaporative fuel discharge operation according to the fifth embodiment will be described below with reference to the flowchart of FIG. 12.

In step 510, it is determined whether the level switch 57 is on. If the level switch 57 is in the on state, it is determined that the evaporative fuel discharge action does not need to be executed, the routine proceeds to step 514 in which the electromagnetic valve 51 is closed, and the routine ends. On the other hand, if the level switch 57 is in the OFF state, it is determined that the evaporative fuel discharge operation needs to be executed, and the routine proceeds to step 516.

In step 516, it is determined whether the temperature T of the cooling water is higher than the predetermined temperature T0 (T> T0). If T> T0, it is determined that the temperature of the coolant does not allow the evaporative fuel discharge action, the routine proceeds to step 514 in which the electromagnetic valve 51 is closed, and the routine ends. On the other hand, if T ≦ T0, it is determined that the temperature of the coolant allows the evaporative fuel discharge action, and the routine proceeds to step 518 in which the electromagnetic valve 51 is opened to introduce negative pressure into the fuel chamber 7, and the routine is It ends.

In the third embodiment, the pressure in the air chamber 6 is maintained at the pressure at which the relief valve 37 opens when the air pump is operated. After the air pump 35 is stopped, the pressure in the air chamber 6 is released through the hole 39 of the relief valve 37 and maintained at atmospheric pressure.

It takes a certain time for the pressure in the air chamber 6 to be fully released by the holes 39, which prevents a sudden decrease in the pressure in the air chamber 6 and the air chamber 6 by the air pump 35. This is because the hole 39 is small to allow an increase in the internal pressure. Therefore, if the pressure in the air chamber 6 is very high, fuel does not flow into the fuel chamber 7 through the fuel filling nozzle. According to the sixth embodiment, fuel can flow into the fuel chamber 7 through the fuel filling nozzle even after the pressure in the air chamber 6 is increased.

A fuel storage device according to a sixth embodiment of the present invention will be described below.

In the sixth embodiment, as shown in FIG. 13, a second relief valve 59 is connected to the second connecting pipe 36. When the pressure in the air chamber 6 is higher than the second predetermined pressure, the second relief valve 59 is opened to release the pressure in the air chamber 6. The second predetermined pressure is lower than the pressure of the fuel when the fuel is supplied by the fuel filling nozzle. The amount of air released from the second relief valve 59 is less than the amount of air pumped by the air pump 35 and is greater than the amount of air flowing through the hole 39 of the relief valve 37.

Parts other than the above-described parts are the same as those of the fuel storage device according to the third embodiment, and thus description thereof is omitted.

An evaporative fuel discharge operation according to the sixth embodiment will be described below.

The evaporative fuel discharge operation according to the sixth embodiment of the present invention is performed in the same manner as the third embodiment. Also, in the same manner as in the third embodiment, the air pump 35 is stopped when the level switch 57 is on or the relief valve 37 is opened.

In the sixth embodiment, when the pressure in the air chamber 6 is higher than the second predetermined pressure after the air pump 35 is stopped, the second relief valve 59 is opened. Therefore, the pressure in the air chamber 6 is lower than the pressure of the fuel when the fuel is supplied by the fuel filling nozzle earlier than in the third embodiment. Thus, fuel can flow into the fuel chamber 7 through the fuel filling nozzle.

Further, according to the sixth embodiment, when the pressure is within a range between the opening pressure of the second relief valve 59 and the opening pressure of the relief valve 37, the rate of increase of the pressure in the air chamber is lower than that of the third embodiment. .

Since the flowchart of the sixth embodiment is the same as that of the third embodiment, the description thereof is omitted.

In the sixth embodiment, the pressure in the air chamber 6 is increased by the air pump 35 and at the same time released by the second relief valve 59 when the pressure in the air chamber 6 is higher than the second predetermined pressure. do. Therefore, the increase rate of the pressure in the air chamber 6 of the sixth embodiment is lower than that of the third embodiment without the second relief valve. Therefore, in the sixth embodiment, the time from when the opener switch 50 is turned on until the cap cover is opened is longer than in the third embodiment. According to the seventh embodiment, even after the pressure in the air chamber 6 increases, fuel can flow into the fuel chamber 7 through the fuel filling nozzle, and the increase rate of the pressure in the air chamber becomes higher than in the sixth embodiment.

A fuel storage device according to a seventh embodiment of the present invention will be described below.

In the seventh embodiment, as shown in FIG. 14, instead of the relief valve 37 and the second relief valve 59, an electromagnetic valve 60 is connected to the second connecting pipe 36. The electromagnetic valve 60 is connected to the output port 47 via the corresponding drive circuit 49 and controlled by the electronic control device 40. The electromagnetic valve 60 blocks the communication between the air chamber 6 and the atmosphere.

A pressure sensor 61 for sensing the pressure in the air chamber 6 is mounted on the upper part 2 of the fuel tank 1. The pressure sensor 61 is connected to the input port 46 via the corresponding AD converter 48.

Parts other than the above-mentioned parts are the same as the parts of the fuel storage device which concerns on 6th Embodiment, and the description is abbreviate | omitted.

An evaporative fuel discharge operation according to the seventh embodiment will be described below.

In the seventh embodiment, it is determined whether the pressure in the air chamber 6 is lower than the maximum predetermined pressure. The maximum predetermined pressure is lower than the pressure at which the dividing wall 5 can be damaged by the pressure in the air chamber 6. When the pressure in the air chamber 6 is lower than the maximum predetermined pressure, the state of the engine and the fuel tank 1 is determined to allow the evaporative fuel discharge action.

Further, in the seventh embodiment, it is determined whether the cap cover opener switch 50 and the level switch 57 are on. When the cap cover opener switch 50 is in the on state and the level switch 57 is in the off state, it is determined that the evaporative fuel discharge action needs to be performed.

Further, in the seventh embodiment, it is determined whether the pressure in the air chamber 6 is lower than the second predetermined pressure. The second predetermined pressure is lower than the pressure when fuel is supplied by the fuel filling nozzle. If the pressure in the air chamber 6 is lower than the second predetermined pressure, it is determined that the pressure in the air chamber 6 allows to open the cap cover.

When the state of the engine and fuel tank 1 permits the evaporative fuel discharge action, and when it is necessary to carry out the evaporative fuel discharge action, the electromagnetic valve 60 is closed and the air pump 35 is pressured in the air chamber 6. It is operated to increase. Therefore, the fuel above the fuel interface is discharged from the fuel chamber 7 via the circulation pipe 23 and the evaporative fuel discharge pipe 24. According to the seventh embodiment, the rate of increase of the pressure in the air chamber 6 is greater than in the sixth embodiment.

When it is not necessary to carry out the evaporative fuel discharge action, the air pump 35 is stopped, the electromagnetic valve 60 is opened to create a pressure lower than the second predetermined pressure in the air chamber 6, and the cap cover is opened. do.

When the state of the engine and fuel tank 1 does not allow evaporative fuel discharge action, the air pump 35 is stopped and the electromagnetic valve 60 creates a pressure lower than the maximum predetermined pressure in the air chamber 6. Is opened.

In the seventh embodiment, the air pump 35 corresponds to means for discharging gas from the space formed above the fuel interface or for raising the level of the fuel interface, and the level switch 57 for detecting the level of the fuel interface. Corresponds to the means.

An evaporative fuel discharge operation according to the seventh embodiment will be described below with reference to the flowchart of FIG. 15.

In step 710, it is determined whether the cap cover opener switch 50 is on. If the opener switch 50 is on, the routine proceeds to step 712. On the other hand, if the opener switch 50 is in the off state, that is, when the supply of fuel to the fuel chamber is completed, the routine proceeds to step 722 in which the electromagnetic valve 60 is closed to keep the pressure in the air chamber 6 relatively high. The process proceeds to step 724 where the air pump 35 is stopped, to step 726 where the fuel supply flag is reset, and the routine ends. The fuel supply flag is set when it is determined that the pressure in the air chamber 6 does not allow the evaporative fuel discharge action, and is reset when the supply of fuel into the fuel chamber is completed.

In step 712, it is determined whether the level switch 57 is on. If the level switch 57 is in the on state, it is determined that the evaporative fuel discharge action does not need to be performed, and the routine proceeds to step 742 in which the air pump 35 is stopped, and the second predetermined pressure in the air chamber 6 is higher than the second predetermined pressure. The process proceeds to step 744 where the electromagnetic valve 60 is opened to create a low pressure, to step 746 where the cap cover is opened, and the routine ends.

On the other hand, in step 712, if the level switch 57 is off, it is determined that the evaporative fuel discharge operation needs to be executed, and the routine proceeds to step 714.

In step 714, it is determined whether the pressure P in the air chamber 6 is lower than the maximum predetermined pressure Pmax (P < Pmax). If P < Pmax, the routine proceeds to step 716. On the other hand, if P≥Pmax, it is determined that the pressure in the air chamber 6 does not allow the evaporative fuel discharge action because the pressure in the air chamber 6 is already higher than the maximum predetermined pressure, and the routine determines that the fuel supply flag is set. Proceeding to 728, proceeds to step 730, where the electromagnetic valve 60 is opened to reduce the pressure in the air chamber 6, and proceeds to step 732.

In step 716, it is determined whether the fuel flag is set. If the flag is reset, it is determined that the pressure in the air chamber 6 allows the evaporative fuel discharge action, the routine proceeds to step 718 in which the electromagnetic valve 60 is closed, and step 720 in which the air pump 35 is operated. The routine ends.

On the other hand, if the fuel supply flag is set, it is determined that the pressure in the air chamber 6 does not allow the evaporative fuel discharge action, and the routine proceeds to step 732.

In step 732, it is determined whether the pressure P in the air chamber 6 is lower than the second predetermined pressure P2 (P <P2). If P &lt; P2, it is determined that the pressure in the air chamber 6 permits the supply of fuel into the fuel chamber 7, the routine proceeds to step 734 where the electromagnetic valve 60 is closed and the fuel chamber 7 The process proceeds to step 736 where the air pump 35 is operated to maintain a relatively high pressure in the air chamber 6 while refueling into, step 738 where the cap cover is opened, and the routine ends.

On the other hand, if P≥P2, it is determined that the pressure in the air chamber 6 does not allow the supply of fuel into the fuel chamber 7, and the routine proceeds to step 739 in which the air pump 35 is stopped, and the electromagnetic valve 60 proceeds to step 740 where it is opened, and the routine ends.

In the second embodiment, when the rate of increase in pressure in the air chamber is large, the fuel can be moved into the fuel chamber. Thus, since the first and second shut-off valves are open, fuel can be introduced into the circulation pipe and the evaporative fuel discharge pipe. According to the eighth embodiment, the rate of increase in pressure in the air chamber is formed to be smaller than the rate of increase in which fuel can be moved into the fuel chamber.

A fuel storage device according to an eighth embodiment will be described below.

In the eighth embodiment, as shown in Fig. 16, an electromagnetic valve 60 is connected to the second connecting pipe 36 instead of the relief valve 37 of the second embodiment. The electromagnetic valve 60 is connected to the output port 47 via the corresponding drive circuit 49 and controlled by the electronic control device 40. The electromagnetic valve 60 blocks the communication between the air chamber 6 and the atmosphere.

A pressure sensor 61 for sensing the pressure in the air chamber 6 is mounted to the upper part 2 of the fuel tank 1. The pressure sensor 61 is connected to the input port 46 via the corresponding AD converter 48.

A fuel level gauge 62 for detecting the amount of fuel in the fuel chamber 7 by detecting the position of the separating wall 5 is mounted to the upper portion 2 of the fuel tank 1. The fuel level gauge 62 is connected to the input port 46 via the corresponding AD converter 48.

The fuel storage device has a temperature sensor 55 for generating a voltage corresponding to the temperature of the cooling water for engine cooling. The temperature sensor 55 is connected to the input port 46 via the corresponding AD converter 48.

Parts other than the above-mentioned parts are the same as the parts of the fuel storage device which concerns on 2nd Embodiment, and the description is abbreviate | omitted.

An evaporative fuel discharge operation according to the eighth embodiment will be described below.

In the eighth embodiment, it is determined whether the temperature of the cooling water is higher than the predetermined temperature, and whether the amount of fuel in the fuel chamber 7 is larger than the predetermined amount of fuel. The predetermined temperature is higher than the temperature of the coolant when the coolant cools the engine in the normal operating state, and the predetermined amount of fuel is sufficient to raise the level of the fuel interface to the highest level in the fuel chamber 7 when the separating wall 5 is lowered. More fuel than

If the temperature of the cooling water is higher than the predetermined temperature and the amount of fuel in the fuel chamber 7 is larger than the predetermined amount of fuel, the state of the engine and the fuel tank 1 is determined to allow evaporative fuel action.

Further, in the eighth embodiment, it is determined whether the level switch 57 is in the off state.

If the level switch 57 is in the OFF state, it is determined that the evaporative fuel discharge operation needs to be performed.

If the state of the engine and fuel tank 1 permits the evaporative fuel discharge action, and if it is necessary to carry out the evaporative fuel discharge action, the evaporative fuel discharge action is executed, that is, the electromagnetic valve 60 is closed and the air pump 35 ) Is operated to increase the pressure in the air chamber (6). Thus, the central portion 5c of the separating wall 5 descends to discharge the evaporated fuel from the space above the fuel interface in the fuel chamber 7.

Further, in the eighth embodiment, while the evaporative fuel discharge operation is performed, the rate of increase of the pressure in the air chamber 6 is based on the pressure in the air chamber 6 detected by the pressure sensor 61 based on the pressure in the fuel chamber 7. It is determined whether the fuel is larger than the increase rate in which a large amount of fuel is moved.

If the increase rate of the pressure in the air chamber 6 is higher than the increase rate at which a large amount of fuel is moved into the fuel chamber 7, the air pump 35 is stopped. On the other hand, if the increase rate of the pressure in the air chamber 6 is lower than the increase rate at which a large amount of fuel is moved into the fuel chamber 7, the air pump 35 is operated. Therefore, the rate of increase of the pressure in the air chamber 6 is kept lower than the rate of increase in which the fuel is moved largely into the fuel chamber 7, thereby preventing the movement of the fuel in the fuel chamber 7.

If the state of the engine and fuel tank does not allow the evaporative fuel ejection action or need to execute the evaporative fuel ejection action, the evaporative fuel ejection action is stopped, ie the air pump 35 is stopped and the electromagnetic valve 60 is open. do.

In the eighth embodiment, the air pump 35 corresponds to means for discharging gas from the space formed above the fuel interface or for raising the level of the fuel interface, and the level switch 57 or the fuel level gauge 62 is connected to the fuel interface. Corresponds to the means for detecting the level of.

The evaporative fuel discharge operation according to the eighth embodiment will be described below with reference to the flowchart of FIG. 17.

In step 810, it is determined whether the temperature T of the cooling water is higher than the predetermined temperature T0 (T> T0). The predetermined temperature is a temperature at which the purge action of the evaporated fuel discharged into the intake passage 52 is allowed. If T &gt; T0, it is determined that the temperature of the cooling water allows the purge action of the evaporated fuel discharged into the intake passage 52, and the routine proceeds to step 812.

On the other hand, if T≤T0, it is determined that the temperature of the coolant does not allow the purge action of the evaporated fuel discharged into the intake passage 52, and the routine proceeds to step 840 in which the electromagnetic valve 60 is opened, and the air pump Proceeding to 35 where step 35 is stopped, the routine ends.

In step 812, it is determined whether the level switch 57 is in an off state. If the level switch 57 is in the OFF state, it is determined that the evaporative fuel discharge action needs to be performed, and the routine proceeds to step 814. On the other hand, if the level switch 57 is in the on state, it is determined that the evaporative fuel discharge action is not necessary, and the routine proceeds to step 840 in which the electromagnetic valve 60 is opened, and the air pump 35 is stopped. Proceeding to 842, the routine ends.

In step 814, it is determined whether the fuel amount F in the fuel chamber 7 is larger than the predetermined fuel amount F0 (F> F0). The predetermined amount of fuel is larger than the amount of fuel sufficient to raise the level of the fuel interface to the highest level in the fuel chamber 7 when the dividing wall 5 is lowered. In step 814, if F> F0, the routine proceeds to step 816.

On the other hand, in step 814, if F ≦ F0, the routine proceeds to step 840 where the electromagnetic valve 60 is opened, proceeds to step 842 where the air pump 35 is stopped, and the routine ends.

In step 816, it is determined whether the electromagnetic valve 60 is closed. If the electromagnetic valve 60 is closed, the routine proceeds to step 818 where the predetermined target pressure Pn is added to the previous target pressure to calculate a new target pressure Pn, and the process proceeds to step 824.

On the other hand, in step 816, if the electromagnetic valve 60 is opened, the routine proceeds to step 836 in which the electromagnetic valve 60 is closed, and the pressure in the air chamber 6 detected by the pressure sensor 61 is set to an initial target. The process proceeds to step 838 where the target pressure Pn is input as the pressure, and the routine ends.

In step 820, it is determined whether the target pressure Pn is higher than the maximum pressure Pmax (Pn> Pmax). The maximum pressure is lower than the pressure at which the dividing wall 5 is damaged by the pressure in the air chamber 6. In step 820, if Pn &gt; Pmax, the routine proceeds to step 822, in which the maximum pressure Pmax is input to the target pressure in order to limit the pressure in the air chamber 6 to the maximum pressure, and the process proceeds to step 824.

On the other hand, in step 820, if Pn ≦ Pmax, the routine proceeds to step 824.

In step 824, it is determined whether the pressure P in the air chamber 6 is lower than the maximum pressure Pmax (P &lt; Pmax). If P &lt; Pmax, it is determined that the pressure in the air chamber 6 allows the evaporative fuel discharge action, and the routine proceeds to step 826. On the other hand, if P≥Pmax, it is determined that the pressure in the air chamber 6 does not allow the evaporative fuel discharge action, the routine proceeds to step 832 in which the electromagnetic valve 60 is opened, and the air pump 35 is stopped. The process proceeds to step 834, where the routine ends.

In step 826, it is determined whether the pressure P in the air chamber 6 is lower than the target pressure Pn (P &lt; Pn). If P &lt; Pn, it is determined that the rate of increase of the pressure in the air chamber 6 is lower than the rate of increase in which the fuel is moved largely in the fuel chamber, and the routine proceeds to step 828 where the electromagnetic valve 60 is closed, 35, operation proceeds to step 830, where the routine ends.

On the other hand, in step 826, if P≥Pn, the increase rate of the pressure in the air chamber 6 is determined to be higher than the increase rate at which fuel is moved largely in the fuel chamber 7, and the routine stops the air pump 35. Proceeding to step 834, the routine ends.

In an eighth embodiment, the evaporated fuel discharged from the fuel chamber is introduced into the intake passage. Thus, the air-fuel ratio of the air-fuel mixture is reduced by the evaporated fuel introduced, that is, the air-fuel ratio is not maintained at a predetermined predetermined air-fuel ratio. According to the ninth embodiment, the air-fuel ratio is maintained at a predetermined predetermined air-fuel ratio when the discharged evaporated fuel is introduced into the intake passage.

A fuel storage device according to a ninth embodiment of the present invention will be described below.

In the ninth embodiment, as shown in Fig. 18, the fuel storage device is provided with an air-fuel ratio sensor 63 for generating a voltage corresponding to the air-fuel ratio in the intake passage. The air-fuel ratio sensor 63 includes an oxygen sensor or a linear sensor that generates a voltage corresponding to the oxygen concentration in the exhaust gas. The air-fuel ratio sensor 63 is connected to the input port 46 via the corresponding AD converter 48.

Parts other than the above-mentioned parts are the same as the parts of the fuel storage device which concerns on 8th Embodiment, and the description is abbreviate | omitted.

An evaporative fuel discharge operation according to the ninth embodiment will be described below.

In the ninth embodiment, it is determined whether the temperature of the cooling water is higher than the predetermined temperature, whether the amount of fuel in the fuel chamber 7 is higher than the predetermined fuel amount, and whether the pressure in the air chamber 6 is lower than the predetermined pressure. The predetermined temperature is higher than the temperature of the coolant when the coolant cools the engine in the normal operating state, and the predetermined amount of fuel is sufficient to raise the level of the fuel interface to the highest level in the fuel chamber 7 when the separating wall 5 is lowered. More, the predetermined pressure is lower than the pressure at which the partition wall is damaged by the pressure in the air chamber.

If the temperature of the coolant is higher than the predetermined temperature, the amount of fuel in the fuel chamber 7 is higher than the predetermined amount of fuel, and the pressure in the air chamber 6 is lower than the predetermined pressure, the state of the engine and the fuel tank 1 is purged of the evaporated fuel. It is judged to allow the action.

Further, in the ninth embodiment, it is determined whether the level switch 57 is in the off state. If the level switch 57 is in the OFF state, it is determined that the evaporative fuel discharge operation needs to be performed.

Further, in the ninth embodiment, it is determined whether the air-fuel ratio detected by the air-fuel ratio sensor 63 is larger than the predetermined air-fuel ratio. The scheduled air-fuel ratio is a predetermined air-fuel ratio. If the detected air-fuel ratio is larger than the predetermined air-fuel ratio, the air-fuel ratio is determined to allow the evaporative fuel discharge operation to proceed.

The state of the engine and fuel tank 1 allows the purge action of the evaporative fuel, it is necessary to carry out the evaporative fuel discharge action, and if the air-fuel ratio allows the evaporative fuel discharge action to proceed, the evaporative fuel discharge action is executed, i. The electromagnetic valve 60 is closed and the air pump 35 operates to increase the pressure in the air chamber 6. Thus, the central portion 5c of the separating wall 5 is lowered to discharge the evaporated fuel from the space above the fuel interface in the fuel chamber 7.

The state of the engine and fuel tank 1 allows the purging action of the evaporative fuel, and if the air-fuel ratio does not allow the evaporative fuel discharge action to proceed even though it is necessary to carry out the evaporative fuel discharge action, the evaporative fuel discharge action is stopped. In other words, the air pump 35 is stopped.

Therefore, according to the ninth embodiment, since the amount of evaporated fuel introduced into the intake passage is controlled, the air-fuel ratio is maintained at a predetermined predetermined air-fuel ratio.

Of course, if the state of the engine and fuel tank 1 does not allow the purge action of the evaporated fuel or need to execute the evaporative fuel discharge action, the evaporative fuel discharge action is stopped, that is, the air pump 35 is stopped.

In the ninth embodiment, the purge action of the evaporated fuel into the intake passage corresponds to means for evacuating gas from the space formed above the fuel interface or for raising the level of the fuel interface, the level switch 57 or the fuel level gauge ( 62 corresponds to means for detecting the level of the fuel interface.

An evaporative fuel discharge operation according to the ninth embodiment will be described below with reference to the flowchart of FIG. 19. In the flowchart, steps 910, 912, and 914 correspond to steps 810, 812, and 814 of FIG. 17, respectively. Therefore, the description is omitted.

In step 914, if F> F0, the routine proceeds to step 916. On the other hand, if F ≦ F0, the routine proceeds to step 924 where the electromagnetic valve 60 is opened, to step 926 where the air pump 35 is stopped, and the routine ends.

In step 916, it is determined whether the pressure P in the air chamber 6 is lower than the maximum pressure Pmax (P &lt; Pmax). If P &lt; Pmax, it is determined that the pressure in the air chamber 6 allows the evaporative fuel discharge action, and the routine proceeds to step 918. On the other hand, if P≥Pmax, it is determined that the pressure in the air chamber 6 does not allow the evaporative fuel discharge action, the routine proceeds to step 924 in which the electromagnetic valve 60 is opened, and the air pump 35 is stopped. Proceed to step 926, where the routine ends.

In step 918, it is determined whether the air-fuel ratio AF is larger than the predetermined predetermined air-fuel ratio AF0 (AF> AF0). If AF> AF0, the air-fuel ratio is judged to allow the evaporative fuel discharge operation to proceed, and the routine proceeds to step 920 where the electromagnetic valve 60 is closed and the air pump 35 is operated, and the routine ends.

On the other hand, if AF≤AF0, it is determined that the air-fuel ratio does not allow the evaporative fuel discharge operation to proceed, the routine proceeds to step 926 in which the air pump 35 is stopped, and the routine ends.

In the third and seventh embodiments, when the pressure in the air chamber continues to increase, the supply of fuel into the fuel chamber is performed. Thus, the increased pressure in the air chamber can cause the fuel in the fuel chamber to flow back into the fuel supply pipe when the supply of fuel into the fuel chamber is stopped. According to the tenth embodiment, the fuel in the fuel chamber is prevented from flowing back into the fuel supply pipe.

A fuel storage device according to a tenth embodiment of the present invention will be described below.

In the tenth embodiment, as shown in FIG. 20, a fuel level gauge 62 for detecting the amount of fuel in the fuel chamber by detecting the position of the separating wall 5 is mounted on the upper portion 2 of the fuel tank 1. do. The fuel level gauge 62 is pendulum-shaped, one end of which is located at the central portion 5c of the separation wall 5, and voltage is generated according to the angle of the pendulum (i.e., the position of the fuel interface). The generated voltage is input to the input port 46 via the corresponding AD converter 48.

Parts other than the above-mentioned parts are the same as the parts of the fuel storage device which concerns on 7th Embodiment, and the description is abbreviate | omitted.

An evaporative fuel discharge operation according to the tenth embodiment will be described below.

The evaporative fuel discharge operation is carried out in the same manner as in the seventh embodiment until the cap cover is opened. Therefore, the description is omitted.

In the tenth embodiment, after the cap cover is opened, the supply of fuel into the fuel chamber 7 is executed until the fuel chamber 7 is completely filled with fuel.

In addition, in the tenth embodiment, the electromagnetic valve 60 is opened to reduce the pressure in the air chamber 6 when a predetermined time elapses. The predetermined time is the time from detecting the fuel chamber 7 to be completely filled with fuel to stopping the supply of fuel into the fuel chamber 7.

Thus, according to the tenth embodiment, the pressure in the air chamber 6 is reduced when the supply of fuel into the fuel chamber 7 is stopped. Thus, backflow of fuel to the fuel supply pipe is prevented.

In the ninth embodiment, the air pump 35 or fuel level gauge 62 corresponds to a means for withdrawing gas from the space formed above the fuel interface or for raising the level of the fuel interface, and the level switch 57 is a fuel Corresponds to the means for detecting the level of the interface.

An evaporative fuel discharge operation according to the tenth embodiment will be described below with reference to the flowcharts of FIGS. 21 and 22.

In step 1010 of FIG. 21, it is determined whether the cap cover opener switch 50 is in an on state. If the opener switch 50 is on, the routine proceeds to step 1012. On the other hand, if the opener switch 50 is in the off state, the supply of fuel into the fuel chamber 7 is not executed, the routine proceeds to step 1050 of FIG. 22 where the end flag is set, and the air pump 35 is stopped. Proceeding to 1052, the electromagnetic valve 60 proceeds to step 1054 where it is opened and proceeds to step 1056. The end flag is set when the cap cover is closed and reset when the first fuel supply flag, the second fuel supply flag, and the counter flag are reset as described below.

In step 1012 of FIG. 21, it is determined whether the level switch 57 is in the on state. If the level switch 57 is in the on state, it is determined that the evaporative fuel discharge action is not necessary, and the routine proceeds to step 1024 in which the second fuel supply flag is set, and to step 1028 in which the electromagnetic valve 60 is opened. The cap cover is opened in step 1030, and the flow proceeds to step 1032 in which the cap cover is opened to supply fuel to the fuel chamber 7. The second fuel supply flag is set when the level switch 57 is in the off state, and is reset when the cap cover is closed.

On the other hand, in step 1012, if the level switch 57 is off, it is determined that the evaporative fuel discharge operation needs to be executed, and the routine proceeds to step 1014.

In step 1014, it is determined whether the pressure P in the air chamber 6 is lower than the maximum pressure Pmax (P &lt; Pmax). The maximum pressure is lower than the pressure at which the dividing wall 5 is damaged by the pressure in the air chamber 6. If P &lt; Pmax, it is determined that the pressure in the air chamber 6 allows the evaporative fuel discharge action, and the routine proceeds to step 1016. On the other hand, if P≥Pmax, it is determined that the pressure in the air chamber 6 does not allow the evaporative fuel discharge action, the routine proceeds to step 1022 in which the first fuel supply flag is set, and the air pump 35 is stopped. Proceeding to step 1026, the electromagnetic valve 60 proceeds to step 1028, where the cap cover proceeds to step 1030, where the cap cover is opened, and proceeds to step 1032. The first fuel supply flag is set when the pressure in the air chamber 6 is higher than the maximum pressure, and reset when the cap cover is closed.

In step 1016, it is determined whether the first fuel supply flag is reset. If the first fuel supply flag has been reset, it is determined that the pressure in the air chamber 6 has not yet reached the maximum pressure, and the evaporative fuel evacuation action is executed, i.e., the routine goes to step 1018 in which the electromagnetic valve 60 is closed. The process proceeds to step 1020 where the air pump 35 is operated to increase the pressure in the air chamber 6, and the routine ends.

On the other hand, in step 1016, if the first fuel supply flag is set, the air pump 35 is not operated even if the pressure in the air chamber 6 is lower than the maximum pressure, and the routine is performed in step 1026, in which the air pump 35 is stopped. Proceeds to step 1028 where the electromagnetic valve 60 is opened, proceeds to step 1030 where the cap cover is opened, and proceeds to step 1032.

In step 1032, it is determined whether the counter flag is reset. The counter flag is set when the fuel chamber is fully filled with fuel and reset when the cap cover is closed. If the counter flag is reset, it is determined that the fuel chamber 7 is not yet fully filled with fuel, and the routine proceeds to step 1034. On the other hand, if the counter flag is set, it is determined that the fuel chamber 7 is completely filled with fuel, and the routine proceeds to step 1042.

In step 1034, it is determined whether the fuel chamber 7 is fully filled with fuel. If the fuel chamber 7 is fully filled with fuel, the routine proceeds to step 1036 where the count is reset, to step 1038 where the counter flag is set, and the routine ends. On the other hand, if the fuel chamber 7 is not fully filled with fuel, the routine proceeds to step 1040 of FIG.

In step 1040, it is determined whether the second fuel supply flag is set. If the second fuel supply flag has been set, it is determined that it is not necessary to carry out the evaporative fuel discharge operation, and the routine ends. On the other hand, if the second fuel supply flag has been reset, it is determined that the evaporative fuel discharge operation needs to be executed, and the routine proceeds to step 1044.

In step 1042, it is determined whether the count t is smaller than the predetermined count t0 (t <t0). The predetermined count is the count between detecting the fuel chamber 7 completely filled with fuel and stopping the supply of fuel into the fuel chamber 7. If t &lt; t0, the routine proceeds to step 1043 where the count is incremented and proceeds to step 1044.

On the other hand, in step 1042, if t≥t0, it is determined that the fuel supply into the fuel chamber 7 is stopped, the routine proceeds to step 1050 in which the end flag is set, and the air pump 35 goes to step 1052 where the air pump 35 is stopped. The flow proceeds to step 1054 where the electromagnetic valve 60 is opened and proceeds to step 1056.

In step 1044, it is determined whether the pressure P in the air chamber 6 is lower than the second predetermined pressure P2 (P <P2). The second predetermined pressure is lower than the pressure of the fuel when fuel is supplied by the fuel filling nozzle. If P <P2, the pressure in the air chamber 6 is determined to allow the supply of fuel into the fuel chamber 7, the routine proceeds to step 1046 where the electromagnetic valve 60 is closed and the air pump 35 Proceeds to step 1048, in which the routine ends.

On the other hand, in step 1044, if P≥P2, it is determined that the pressure in the air chamber 6 does not allow the supply of fuel into the fuel chamber 7, and the routine proceeds to step 1052 in which the air pump 35 is stopped. The flow proceeds to step 1054 where the electromagnetic valve 60 is opened and proceeds to step 1056.

In step 1056, it is determined whether the end flag is set. If the end flag is set, it is determined that the supply of fuel into the fuel chamber 7 is completed, and the routine proceeds to step 1058 in which the first fuel supply flag is reset, and proceeds to step 1060 in which the second fuel supply flag is reset. The counter flag proceeds to step 1062 with the reset flag, the end flag proceeds to step 1064 with the reset, and the routine ends.

On the other hand, if the end flag is reset in step 1056, it is determined that the supply of fuel into the fuel chamber 7 is not completed, and the routine ends.

In the first to tenth embodiments, the fuel pump 19 is located in the fuel tank. The shape of the fuel pump 19 is not simple so that the separating wall 5 does not contact the fuel interface around the fuel pump 19. Thus, a space can be formed between the fuel interface around the fuel pump 19 and the separating wall 5. According to the eleventh embodiment, no space is formed between the fuel interface around the fuel pump 19 and the dividing wall 5.

A fuel storage device according to an eleventh embodiment of the present invention will be described below.

In the eleventh embodiment, as shown in FIG. 23, the fuel pump 19 is located outside of the fuel tank 1. The fuel pump 19 is connected to the fuel filter 21 via the fuel pump pipe 19a. The fuel pump pipe 19a extends below the lower opening of the fuel supply pipe 13 through the lower portion 3. The fuel filter 21 is located in the fuel chamber 7.

The pressure regulator 20 is located downstream of the fuel pump 19. The fuel return passage 64 extends from the pressure regulator 20 into the fuel chamber 7. The fuel return passage 64 serves to return excess fuel into the fuel chamber 7.

In the eleventh embodiment, the fuel storage device does not have a pump chamber, so the evaporative fuel discharge pipe is excluded. The level switch 57 is located in the lower part 3 adjacent to the fixing part 8.

Parts other than the above-mentioned parts are the same as the parts of the fuel storage device which concerns on 4th Embodiment, and the description is abbreviate | omitted.

Therefore, according to the eleventh embodiment, since the shape inside the fuel tank is simplified, no space is formed between the separating wall 5 and the fuel interface.

In the eleventh embodiment, the purge action of the evaporated fuel into the intake passage corresponds to means for evacuating gas from the space formed above the fuel interface or for raising the level of the fuel interface, and the level switch 57 is the level of the fuel interface. Corresponds to means for detecting.

Of course, the eleventh embodiment is applicable to any of the above-described embodiments.

In the first embodiment, after the supply of fuel into the fuel chamber 7 is completed, evaporated fuel is generated from the fuel in the fuel supply pipe 13. According to the twelfth embodiment, generation of evaporated fuel from fuel in the fuel supply pipe 13 is prevented.

In the twelfth embodiment, as shown in FIG. 24, the lower opening of the fuel supply pipe 13 is mounted on the fixing part 8. The fuel supply pipe 13 is located above its lower opening.

Suitably, the lower opening of the fuel supply pipe 13 is located above the highest position in the fuel chamber 7. In this case, the fuel in the fuel supply pipe 13 is completely excluded.

Parts other than the above-mentioned parts are the same as the parts of the fuel storage device which concerns on 1st Embodiment, and the description is abbreviate | omitted.

Therefore, according to the twelfth embodiment, the fuel in the fuel supply pipe 13 flows into the fuel chamber 7 by its own weight as the fuel in the fuel chamber 7 is reduced. Thus, generation of evaporated fuel from the fuel in the fuel supply pipe 13 is prevented.

In the twelfth embodiment, the supply of fuel into the fuel chamber corresponds to means for evacuating gas or raising the level of the fuel interface from the space formed above the fuel interface.

Of course, the twelfth embodiment is applicable to any of the above-described embodiments.

In the twelfth embodiment, the fuel in the fuel supply pipe 13 flows into the fuel chamber 7 as the fuel in the fuel chamber 7 is reduced. Therefore, a predetermined time is required for the fuel in the fuel supply pipe 13 to flow completely into the fuel chamber 7. Thus, before all the fuel in the fuel supply pipe 13 is flowed into the fuel chamber 7, evaporated fuel can be generated from the fuel in the fuel supply pipe 13. According to the thirteenth embodiment, generation of evaporated fuel in the fuel supply pipe 13 is further prevented.

In the thirteenth embodiment, as shown in FIG. 25, instead of the atmospheric communication pipe 33, an air chamber 6 is connected to the air pump 35 via the first connecting pipe 34. The first connecting pipe 34 is connected to the electromagnetic valve 60 via the second connecting pipe 36. The electromagnetic valve 60 is connected to the output port 47 via the corresponding drive circuit 49. The electromagnetic valve 60 is controlled by the electronic control device 40.

A pressure sensor 61 for sensing the pressure in the air chamber 6 is mounted to the upper part 2 of the fuel tank 1. The pressure sensor 61 is connected to the input port 46 via the corresponding AD converter 48.

A fuel level gauge 62 which detects the amount of fuel in the fuel chamber 7 by detecting the position of the separating wall 5 is mounted on the upper portion of the fuel tank 1. The fuel level gauge 62 is connected to the input port 46 via the corresponding AD converter 48.

Parts other than the above-mentioned parts are the same as the parts of the fuel storage device which concerns on 12th Embodiment, and the description is abbreviate | omitted.

An evaporative fuel discharge operation according to the thirteenth embodiment will be described below.

The evaporative fuel discharge operation is carried out in the same manner as in the tenth embodiment until the cap cover is opened. Therefore, the description is omitted.

In the thirteenth embodiment, after the cap cover is opened, the supply of fuel into the fuel chamber 7 is executed until the fuel chamber 7 is completely filled with fuel.

In addition, in the thirteenth embodiment, the electromagnetic valve 60 is opened so that the pressure in the air chamber 6 is reduced when a predetermined time elapses. The predetermined time is the time from the detection time of the fuel chamber 7 which is fully filled with fuel to immediately after the supply of fuel into the fuel chamber 7 is stopped.

Thus, according to the thirteenth embodiment, the pressure in the air chamber 6 is reduced when the supply of fuel into the fuel chamber 7 is stopped. Thus, since the fuel in the fuel supply pipe 13 flows into the fuel chamber 7, generation of evaporated fuel in the fuel supply pipe 13 is further prevented.

In the thirteenth embodiment, the air pump 35 corresponds to means for discharging gas from the space formed above the fuel interface or for raising the level of the fuel interface, and the level switch 57 or the fuel level gauge 62 is connected to the fuel. Corresponds to the means for detecting the level of the interface.

An evaporative fuel discharge operation according to the thirteenth embodiment will be described below with reference to the flowcharts of FIGS. 26 and 27. In the flowchart, steps 1310 to 1360 except for step 1342 correspond to steps 1010 to 1060 of FIGS. 21 and 22, respectively, and thus description thereof is omitted.

In step 1342, it is determined whether the count t is less than the predetermined count t1 (t &lt; t1). The predetermined count is a count from the detection of the fuel chamber 7 which is completely filled with fuel to immediately after the supply of fuel into the fuel chamber 7 is stopped. If t <t1, the routine proceeds to step 1343 where the count is incremented and proceeds to step 1344.

On the other hand, in step 1342, if t≥t1, it is determined that the supply of fuel into the fuel chamber 7 is stopped, the routine proceeds to step 1350 in which an end flag is set, and the air pump 35 is stopped. Proceeding to 1352, the process proceeds to step 1354 where the electromagnetic valve 60 is opened and proceeds to step 1356.

In the embodiment described above, although the air pump is actuated or the electromagnetic valve 60 is opened based on the opening of the relief valve, or the pressure in the air chamber 6, or the level switch 57, the position of the separation wall 5 The air pump may be actuated or the electromagnetic valve 60 may be opened on the basis.

A fuel storage device according to a fourteenth embodiment of the present invention will be described below.

In a fourteenth embodiment, as shown in FIG. 28, the fuel storage device includes a fuel tank body 140. The fuel tank body 140 has an upper portion 91 and a lower portion 92 which are generally cup-shaped. The upper portion 91 and the lower portion 92 are connected to each other at their flange portions 91a and 92a.

A fuel container 94 that forms a fuel chamber 93 for storing and containing fuel therein is mounted inside the fuel tank body 140. The fuel container 94 has a rigid and deformable rectangular top wall 95, a rigid and deformable rectangular bottom wall 96 and a peripheral portion 95a of the upper wall 95 as shown in FIG. 29. It is connected to the periphery 96a of the lower wall 96 and has a rigid and deformable strip-shaped wall or connecting wall 97.

As shown in FIG. 30, the upper wall 95 and the lower wall 96 are deformed in such a manner that they expand outward as the amount of fuel in the fuel container 94 increases. As a result of the deformation of the upper wall 95 and the lower wall 96, the connecting wall 97 is curved inward. Thus, the volume of the fuel container 94 is increased.

On the other hand, when the amount of fuel in the fuel container 94 is reduced, the outwardly expanding top wall 95 and the bottom wall 96 and the inwardly curved connecting wall 97 return to their original shapes as shown in FIG. 29. do. Thus, the volume of the fuel container 94 is reduced.

31, when the amount of fuel in the fuel container 94 is reduced, the upper wall 95 and the lower wall 96 are deformed in such a manner as to expand inwardly. As a result of the deformation of the upper wall 95 and the lower wall 96, the connecting wall is curved inward. Thus, the volume of the fuel container 94 is reduced.

The rigidity of the connecting wall 97 is greater than the rigidity of the upper wall 95 and the lower wall 96.

The fuel entry opening 98 is formed in the center of the lower wall 96 of the fuel container 94. A connecting pipe opening 99 is formed in the center of the lower portion 92 of the fuel tank body 140. The fuel container 94 is located in the fuel tank body 140 in such a way that the fuel entry and exit openings 98 are aligned with the connecting pipe openings 99.

The air chamber 110 is formed outside the fuel container 94 and inside the fuel tank body 140. The fuel level sensor 111 which detects the movement amount or the position of the upper wall 95 of the fuel container 94 to calculate the amount of fuel in the fuel container 94 is inside the upper portion 91 of the fuel tank body 140. Mounted on the surface.

In addition, an air inlet opening 112 is formed in the upper portion 91 of the fuel tank body 140. When the volume of the fuel container 94 is reduced or increased, the volume of the air chamber 110 is increased or decreased. At this time, air may flow into or out of the air chamber 110 via the air inlet and opening 112. Thus, the fuel container 94 is easily deformed.

A filter 113 is inserted into the air inlet opening 112 to prevent material other than air from flowing into the air chamber 110.

One end of the fuel pipe 114, which introduces fuel into the fuel container 94 and exits the fuel container 94, has a fuel inlet opening 98 of the fuel container 94 and a lower portion of the fuel tank body 140. It is inserted into and connected to the connecting pipe opening 99 of 92.

The other end of the fuel pipe 114 is the lower end of the fuel supply pipe 115 for supplying fuel to the fuel container 94, and the fuel introduction pipe for introducing fuel from the fuel container 94 to the fuel pump device 116. Is connected to one end of 117. The other end of the fuel introduction pipe 117 is connected to the fuel pump device 116.

The fuel pump device 116 pumps fuel in the fuel container 94 and supplies fuel to an injector (not shown) of the engine. One end of the evaporative fuel pipe 118 for the pump for discharging the evaporated fuel from the fuel pump apparatus 116 is connected to the fuel pump apparatus 116. The other end of the evaporative fuel pipe 118 for the pump is connected to the fuel supply pipe 115 adjacent the upper opening of the fuel supply pipe 115. In addition, one end of the fuel delivery pipe 120 for transferring fuel from the fuel pump device 116 to the injector is connected to the fuel pump device 116.

One end of the evaporative fuel pipe 150 for the vessel for discharging evaporated fuel from the fuel vessel 94 is connected to the top wall 95 of the fuel vessel 94. The other end of the evaporative fuel pipe 150 for the vessel is connected to the fuel pump device 116. In addition, an evaporative fuel pipe shutoff valve 149 or a vessel closure valve is disposed within one end of the evaporative fuel pipe 150 for the vessel.

The evaporative fuel pipe shutoff valve 149 has a float 151, the density of the float being less than the density of the fuel.

The opening of the evaporative fuel pipe 150 for the vessel opened into the fuel vessel 94 corresponds to the discharge passage opened to the space above the fuel interface, and the evaporative fuel pipe shutoff valve 149 blocks the discharge passage described above. Corresponds to the shut-off valve.

One end of the evaporative fuel pipe 121 for discharging the evaporated fuel adjacent the upper opening 119 is connected to the fuel supply pipe 115 at the upper opening side above the other end of the evaporative fuel pipe 118 for the pump. The other end of the evaporative fuel pipe 121 is connected to a charcoal canister 122 that adsorbs the evaporated fuel at the top and temporarily stores the evaporated fuel therein.

Activated carbon 123 that adsorbs the upper evaporative fuel is located in the charcoal canister 122. The interior of the charcoal canister 122 is divided by activated carbon 123. Therefore, the evaporative fuel chamber 124 is formed on one side of the activated carbon 123, and the air chamber 125 is formed on the other side of the activated carbon 123.

The other end of the evaporative fuel pipe 121 described above is connected to the evaporative fuel chamber 124 in the charcoal canister 122. In addition, a canister evaporative fuel pipe 126 for discharging the evaporated fuel adsorbed on the activated carbon 123 from the charcoal canister 122 to the intake passage 127 of the engine is connected to the evaporative fuel chamber 124. The other end of the evaporative fuel pipe 126 for the canister is connected to a surge tank 128 formed in the intake passage 127.

An evaporative fuel amount control valve 129 for opening and closing the canister evaporative fuel pipe 126 is disposed in the canister evaporative fuel pipe 126. The evaporative fuel amount control valve 129 is controlled by a control device (not shown). One end of the air pipe 130 for introducing air into the air chamber 125 of the charcoal canister 122 is connected to the air chamber 125. The other end of the air pipe 130 is connected to an air cleaner 131 disposed in the intake passage 127. A shutoff valve 132 for opening and closing the air pipe 130 is disposed in the air pipe 130. The shutoff valve 132 is controlled by a control device (not shown). A throttle valve 133 that controls the amount of air supplied to the engine body 180 of the engine is disposed in the intake passage 127.

In the fourteenth embodiment, when the evaporative fuel in the charcoal canister 122 needs to be introduced into the intake passage 127, the evaporative fuel amount control valve 129 is opened. The evaporative fuel amount control valve 129 is normally closed. Accordingly, when the evaporative fuel amount control valve 129 is opened, the negative pressure in the surge tank 128 is introduced into the charcoal canister 122 via the evaporative fuel pipe 126 for the canister, and the air in the air cleaner 131 It is introduced into charcoal canister 122 via air pipe 130. Thus, the evaporated fuel in the charcoal canister 122 is introduced into the intake passage 127.

The evaporative fuel amount control valve 129 is also controlled based on the operating state of the engine to control the amount of evaporative fuel to be introduced into the intake passage 127 in such a manner that a predetermined predetermined air-fuel ratio can be obtained. Thus, the evaporative fuel amount control valve 129 corresponds to means for controlling the amount of evaporated fuel discharged into the intake passage 127, and the shutoff valve 132 corresponds to means for controlling the introduction of air into the charcoal canister 122. .

In a fourteenth embodiment, when a leak in the fuel system in communication with the charcoal canister 122 needs to be detected, a negative pressure is introduced into the fuel system extending from the charcoal canister 122 to the fuel tank body 140, The post-evaporation fuel amount control valve 129 and the shutoff valve 132 are closed to close the fuel system described above. Next, if an increase in pressure in the fuel system towards atmospheric pressure is detected by a pressure sensor (not shown), the fuel system determines that it has a leaked portion. Thus, the evaporative fuel amount control valve 129 and the shutoff valve 132 correspond to means for detecting leakage of fuel.

A fuel pump device according to a fourteenth embodiment of the present invention will be described in detail below.

In the fourteenth embodiment, as shown in FIG. 32, the fuel pump device 116 includes a pump chamber 153 formed by the housing 152. The pump chamber 153 is divided into a pump chamber portion 155 and a sub tank chamber 156 by a pump chamber partition wall 154.

The pump chamber dividing wall 154 includes a vertical wall 154a extending generally vertically and downwardly from an inner surface of the upper wall of the housing 152, and a housing 152 above the inner surface of the lower wall of the housing 152. A horizontal wall 154b extending horizontally to an inner surface of the sidewall of the substrate.

One end of the evaporative fuel pipe 118 for the pump, which discharges the evaporated fuel from the pump chamber portion 155, is connected to the top wall of the housing 152. An opening at one end of the evaporative fuel pipe 118 for the pump is opened adjacent to the top wall of the housing 152 in the pump chamber portion 155.

A fuel pump 157, which supplies fuel from the sub tank chamber 156 to the injection device via the fuel transfer pipe 120, is located in the sub tank chamber 156. A first fuel filter 158 that filters the fuel pumped into the fuel pump 157 is connected to the bottom wall of the fuel pump 157. In addition, a pressure regulator 159 for adjusting the pressure of the fuel pumped by the fuel pump 157 is disposed in the fuel transfer pipe 120 in the sub tank chamber 156.

An upper end of the fuel return pipe 161 that returns a portion of the fuel pumped by the fuel pump 157 to the sub tank chamber 156 is connected to the pressure regulator 159. In addition, a second fuel filter 160 that filters fuel pumped from the fuel pump 157 is disposed in the fuel transfer pipe 120 between the pressure regulator 159 and the fuel pump 157.

The lower tip 162 of the fuel return pipe 161 is generally horizontally oriented and tapered in such a way that the diameter of the tip 162 decreases as the tip 162 approaches its opening. The lower tip portion 162 is mounted in the negative pressure generating housing 163 which generates negative pressure by returning or recirculating a portion of the fuel pumped by the fuel pump 157 to the sub tank chamber 156. The negative pressure generating housing 163 includes a trumpet shaped fuel discharge pipe 164 tapered in such a manner that the diameter of the fuel discharge pipe 164 increases as the fuel discharge pipe 164 approaches its opening.

The fuel discharge pipe 164 is aligned with the lower tip 162. In addition, the lower end of the evaporative fuel pipe 150 for the vessel is mounted in the negative pressure generating housing 163.

The evaporative fuel pipe 150 for the vessel in the sub tank chamber 156 has a negative pressure introduction pipe 165 for the sub tank chamber for introducing a negative pressure into the sub tank chamber 156. The negative pressure introduction pipe 165 opens into the sub tank chamber 156 in the upper region in the sub tank chamber 156. Further, the diameter of the negative pressure introduction pipe 165 is smaller than the diameter of the evaporative fuel pipe 150 for the container.

Vertical annular walls 167 extending vertically and downwardly from the horizontal wall 154b of the pump chamber separation wall 154 are disposed on the horizontal wall 154b. The vertical annular wall 167 defines a fuel inlet passage 166 for introducing fuel into the sub tank chamber 156. The position of the upper opening of the fuel inlet passage 166 is lower than the position of the bottom wall surface of the fuel introduction pipe 117.

A horizontal annular wall 168 extending horizontally from the vertical annular wall 167 toward the fuel discharge pipe 164 is disposed on the lower end of the vertical annular wall 167. The horizontal annular wall 168 defines a fuel passage passage 169 for passing fuel discharged from the fuel discharge pipe 164.

A partition wall 170 having a mesh structure for separating gas from fuel is disposed in the vertical annular wall 167 and the pump chamber portion 155. The partition wall 170 extends upwardly from the bottom surface of the horizontal annular wall 168 into the fuel inflow passage 166. Thus, the dividing wall 170 crosses the fuel passage passage 169.

In addition, the dividing wall 170 extends into the pump chamber portion 155 through the vertical annular wall 167. The side of the dividing wall 170 in the vertical annular wall 167 extends to the inner surface of the vertical annular wall 167. Thus, the dividing wall 170 divides the fuel inlet passage 166 into two parts.

In addition, the dividing wall 170 extends into the pump chamber portion 155 under the horizontal wall 154b. The upper end of the dividing wall 170 in the pump chamber portion 155 is located higher than the opening of the fuel introduction pipe 117.

In addition, the side of the dividing wall 170 in the pump chamber portion 155 is connected to the inner surface of the cylindrical wall of the housing 152. The lower end of the dividing wall in the pump chamber portion 155 is connected to the horizontal wall 154b.

The operation of the fuel pump device according to the fourteenth embodiment of the present invention will be described below.

When the fuel pump 157 is operated to supply fuel in the fuel container 94 to the injector, the fuel in the sub tank chamber 156 is pumped into the fuel pump 157 via the first fuel filter 158. . Fuel pumped into the fuel pump 157 is supplied to the pressure regulator 159 via the second fuel filter 160. When the pressure of the fuel is higher than the predetermined pressure in the pressure regulator 159, a portion of the fuel is returned to the sub tank chamber 156 via the fuel return pipe 161. Thus, the pressure regulator 159 and the fuel return pipe 161 correspond to means for recirculating the fuel. Thus, the pressure of the fuel is maintained at the predetermined pressure.

Residual fuel having a predetermined pressure is supplied to the injection device via the fuel transfer pipe 120.

The fuel returned to the sub tank chamber 156 via the fuel return pipe 161 is discharged from the lower tip portion 162 to the negative pressure generating housing 163. The venturi effect of the tapered lower tip 162 increases the flow rate of fuel exiting the lower tip 162. Fuel with increased flow rate is flowed into the fuel passage passage 169 via the fuel discharge pipe 164.

When fuel is discharged from the lower tip portion 162 to the fuel discharge pipe 164 to increase the flow rate, negative pressure is generated in the negative pressure generating housing 163. Accordingly, the fuel return pipe 161 and the negative pressure generating housing 163 correspond to means for generating negative pressure.

The negative pressure generated in the negative pressure generating housing 163 is introduced into the space above the fuel interface in the fuel container 94 via the evaporative fuel pipe 150 for the container, and for the evaporative fuel pipe 150 for the container and the sub tank. The negative pressure introduction pipe 165 is introduced into the space above the fuel interface in the sub tank chamber 156. Thus, the evaporative fuel pipe 150 for the vessel and the negative pressure introduction pipe 165 for the sub tank correspond to a passage or means for introducing the negative pressure.

In the fourteenth embodiment, the diameter of the evaporative fuel pipe 150 for the vessel is larger than the diameter of the negative pressure inlet pipe 165 for the sub tank. Accordingly, a negative pressure is introduced into the fuel container 94 to preferentially discharge the gas containing the evaporated fuel and air from the fuel container 94. Accordingly, the negative pressure introduction pipe for the sub tank corresponds to means for promoting preferential discharge of the gas from the fuel container 94.

When the negative pressure is introduced into the fuel container 94, evaporated fuel and air are discharged from the fuel container 94 to the negative pressure generating housing 163, so that the level of the fuel interface in the fuel container 94 is reduced to the fuel chamber ( 93) to the highest position within. Accordingly, the fuel pump 157 corresponds to means for discharging gas from the space formed above the fuel interface or raising the level of the fuel interface.

In the fourteenth embodiment, when gas such as evaporated fuel or air is completely discharged from the fuel container 94, the fuel container 94 remains free of gas therein as long as the fuel pump 157 operates. . In addition, when the fuel container 94 is maintained without containing gas therein, the upper surface of the fuel container 94 represents the exact amount of fuel in the fuel container 94. Therefore, according to the fourteenth embodiment, the fuel amount in the fuel container 94 is accurately detected.

If the negative pressure continues to be introduced into the fuel container 94 after the evaporated fuel and air are discharged from the fuel container 94, fuel may leak from the fuel container 94 into the evaporative fuel pipe 150 for the container. Therefore, when the evaporated fuel and air are discharged from the fuel container 94, the introduction of the negative pressure into the fuel container 94 must be stopped.

In the fourteenth embodiment, when the evaporative fuel and air are completely discharged from the fuel container 94 and the level of the fuel interface in the fuel container 94 reaches the evaporative fuel pipe shutoff valve 149, the evaporative fuel pipe shutoff valve ( 149 blocks the evaporative fuel pipe 150 for the vessel. Thus, the evaporative fuel pipe shutoff valve 149 corresponds to means for stopping the introduction of underpressure into the fuel container 94. The evaporative fuel pipe shutoff valve 149 also corresponds to means for preventing the leakage of fuel from the fuel container 94.

After the evaporative fuel pipe shutoff valve 149 shuts off the evaporative fuel pipe 150 for the vessel, the negative pressure is only introduced into the space above the fuel interface in the sub tank chamber 156.

When the negative pressure is introduced into the space above the fuel interface in the sub tank chamber 156, the evaporated fuel and air are discharged from the space to the negative pressure generating housing 163. The negative pressure introduced raises the level of the fuel interface in the sub tank chamber 156, and the fuel is introduced into the sub tank chamber 156 via the fuel inlet passage 166 from the pump chamber portion 155. Thus, the level of the fuel interface in the sub tank chamber 156 is maintained at a predetermined height as long as there is fuel in the pump chamber portion 155. Therefore, when the fuel pump device 116 is inclined and the fuel interface in the sub tank chamber 156 is inclined, the fuel is prevented from being exhausted around the first fuel filter 158 which introduces the fuel into the fuel pump 157. do. Accordingly, the fuel return pipe 161 and the negative pressure generating housing 163 correspond to means for preventing fuel depletion.

Evaporated fuel and air discharged from the space above the fuel interface in the fuel container 94 and the sub tank chamber 156 are mixed with fuel in the negative pressure generating housing 163. Fuel including evaporated fuel and air is discharged to the fuel passage passage 169 via the fuel discharge pipe 164. Fuel discharged to the fuel passage passage 169 passes through the lower opening of the fuel inlet passage 166. At this time, the evaporated fuel and air contained in the fuel are moved upward due to the low density. Evaporative fuel and air are then discharged from the sub tank chamber 156 to the pump chamber portion 155 via one of the portions of the fuel inlet passage 166 divided by the separating wall 170.

As described above, in the fourteenth embodiment, the fuel inflow passage 166 is a fuel introduction passage for introducing fuel into the sub tank chamber 156 and an evaporative fuel discharge passage for discharging evaporated fuel from the sub tank chamber 156. Works. Thus, there is no need to provide another evaporative fuel discharge passage in addition to the fuel inlet passage 166. Therefore, the fuel pump device can be made compact because the fuel inlet passage 166 acts as a fuel introduction and evaporative fuel discharge passage.

Also, in the fourteenth embodiment, when the fuel discharged to the fuel passage passage 169 flows below the lower opening of the fuel inlet passage 166, the fuel passes through the dividing wall 170. Thus, the evaporated fuel and air are separated from the fuel by the separation wall 170 and are discharged to the pump chamber portion 155 via the fuel inlet passage 166. Thus, the dividing wall 170 corresponds to means for separating gas from the fuel.

In addition, in the fourteenth embodiment, the fuel passage passage 169 is directly connected to the fuel suction passage 166 and is perpendicular to the fuel suction passage 166. Thus, the evaporative fuel and the air can be easily raised to be separated from the fuel. Accordingly, fuel passage passage 169 and fuel inlet passage 166 correspond to means for separating or discharging gas from the fuel.

Evaporated fuel discharged to the pump chamber portion 155 is introduced into the charcoal canister 122 via the evaporative fuel pipe 118 for the pump. The lower opening of the evaporative fuel pipe 118 for the pump opens into the interior of the pump chamber portion 155 adjacent the top wall of the housing 152. Thus, the evaporated fuel in pump chamber portion 155 may be introduced into charcoal canister 122 until the amount of fuel in pump chamber portion 155 is small.

The fuel in the sub tank chamber 156 is heated by the fuel pump 157. Thus, the temperature of the fuel in the sub tank chamber 156 is higher than the temperature of the fuel in the pump chamber portion 155. If a relatively high temperature fuel is mixed with a relatively low temperature fuel in the pump chamber portion 155, a large amount of evaporated fuel may be generated. In addition, when the amount of fuel in the sub tank chamber 156 is very small, if fuel flows from the sub tank chamber 156 to the pump chamber portion 155, the fuel may be exhausted around the first fuel filter 158. Thus, the flow of fuel from the sub tank chamber 156 to the pump chamber portion 155 must be prevented.

According to the fourteenth embodiment, the fuel passage passage 169 is perpendicular to the fuel inlet passage 166. Thus, the flow of fuel from the fuel passage passage 169 into the pump chamber portion 155 is prevented. Accordingly, the fuel passage passage 169 and the fuel inlet passage 166 correspond to means for preventing the outflow of fuel, generation of evaporated fuel, or exhaustion of fuel.

As the fuel in the sub tank chamber 156 is supplied to the injector by the fuel pump device 116, the fuel in the fuel container 94 is introduced into the pump chamber portion 155 via the fuel introduction pipe 117. A portion of the fuel introduced into the pump chamber portion 155 via the fuel introduction pipe 117 passes through the separation wall 170. Thus, the evaporated fuel contained within the fuel in fuel container 94 is separated within pump chamber portion 155.

In the fourteenth embodiment, the fuel introduction pipe 117 is located at a lower position than the lower wall 96 of the fuel container 94. Thus, fuel in fuel container 94 can be fully introduced into pump chamber portion 155. In addition, the upper opening of the fuel inlet passage 166 is located at a lower position than the lower surface of the pipe wall of the fuel introduction pipe 117. Thus, fuel in fuel chamber portion 155 may be fully introduced into sub tank chamber 156. Therefore, when the amount of fuel in the fuel container 94 becomes small, the fuel in the fuel container 94 can be introduced into the sub tank chamber 156 due to the height difference between the fuel container 94 and the fuel introduction pipe 117. have.

When the fuel pump device 116 is inclined, the fuel interface in the fuel inlet passage 166 or the pump chamber portion 155 reaches the bottom end of the fuel inlet passage 166. When the level of the fuel interface exceeds the bottom end of the fuel intake passage 166 and exceeds the bottom position of the top end of the fuel intake passage 166, the fuel in the sub tank chamber 156 is pump chamber portion 155. Flows into. As described above, the flow of fuel from the sub tank chamber 156 into the pump chamber portion 155 may result in the generation of evaporated fuel in the pump chamber portion 155. In addition, when the fuel amount in the sub tank chamber 156 is very small, if fuel flows from the sub tank chamber 156 to the pump chamber portion 155, the fuel may be exhausted around the first fuel filter 158.

According to the fourteenth embodiment, the vertical annular wall 167 extends relatively broadly downward from the horizontal wall 154b. Thus, the level of the fuel interface is prevented from exceeding the lowermost end of the fuel inlet passage 166 and from exceeding the lowest position of the uppermost end of the fuel inlet passage 166. Thus, the vertical annular wall 167 corresponds to means for preventing outflow of fuel or generation of evaporative fuel.

In addition, the fuel outflow prevention effect may affect the length or size of the fuel inlet passage 166 (or the relationship between the positions of the top and bottom ends of the fuel inlet passage 166) and the horizontal line of the fuel interface within the fuel inlet passage 166. Depends only on the angle of inclination. In other words, the fuel outflow prevention effect can be achieved regardless of the position of the fuel inlet passage 166. Thus, the freedom of selection of the position of the fuel inlet passage 166 is increased.

In addition, in order to facilitate the separation of the gas from the fuel discharged from the fuel passage passage, the fuel is preferably left in the lower portion of the fuel inlet passage for a long time. According to another embodiment as shown in FIG. 34, the fuel passage passage is directed downward and connected to the fuel inlet passage. Thus, the fuel discharged from the fuel passage passage flows downward in the fuel inlet passage. Thus, fuel can remain for a long time under the fuel inlet passage.

A fuel pump device according to a fifteenth embodiment of the present invention will be described below.

In the fourteenth embodiment, when fuel is supplied to the fuel container 94 via the fuel supply pipe 115, the fuel is introduced into the fuel pump device 116 via the fuel introduction pipe 117. Fuel introduced into the fuel pump device 116 flows into the sub tank chamber 156. Thus, the level of the fuel interface in the sub tank chamber 156 rises.

In the fourteenth embodiment, the interior of the fuel container 94 is in direct communication with the interior of the sub tank chamber 156 via the negative pressure introduction pipe 165 for the sub tank chamber. Thus, the evaporative fuel and air can be flowed back to the fuel vessel 94 via the evaporative fuel pipe 150 for the vessel. According to the fifteenth embodiment, gas is prevented from flowing back from the sub tank chamber 156 into the fuel container 94 during the supply of fuel.

In the fifteenth embodiment, as shown in FIGS. 35 and 36, the negative pressure introduction pipe 165 for the sub tank chamber is not disposed in the evaporative fuel pipe 150 for the vessel. The negative pressure introduction pipe 173 for the sub tank chamber is disposed in the sub tank chamber 156 irrespective of the evaporative fuel pipe 150 for the container. The upper opening of the negative pressure introduction pipe 173 for the sub tank chamber is opened into the sub tank chamber 156 in the upper region in the sub tank chamber 156. On the other hand, the lower opening of the negative pressure introduction pipe 173 for the sub tank chamber is opened into the negative pressure generating housing 163. The diameter of the lower opening of the negative pressure introduction pipe 173 for the sub tank chamber is smaller than the diameter of the evaporative fuel pipe 150 for the container.

Parts other than the above-mentioned parts are the same as the fuel pump apparatus which concerns on 14th Embodiment, and the description is abbreviate | omitted.

The operation of the fuel pump apparatus according to the fifteenth embodiment of the present invention will be described below.

When fuel is introduced into fuel container 94 via fuel supply pipe 115, fuel is introduced into sub tank chamber 156. Thus, the level of the fuel interface in the sub tank chamber 156 rises. In the fifteenth embodiment, the space above the fuel interface in the sub tank chamber 156 is not in direct communication with the interior of the fuel container 94. Thus, backflow of evaporated fuel and air from the sub tank chamber 156 is prevented during the supply of fuel. Thus, the amount of evaporated fuel and air in fuel container 94 is maintained in small amounts before fuel pump 157 is operated. Thus, when the fuel pump 157 is operated, evaporated fuel and air can be quickly discharged from the fuel container 94.

Operations other than those described above are the same as those of the fuel pump apparatus according to the fourteenth embodiment, and thus description thereof is omitted.

In the above-described embodiment, a sensor for detecting a gas containing evaporated fuel in the space above the fuel interface in the fuel chamber may be used instead of the level switch. In addition, the evaporative fuel discharge action may be controlled to open and close the above-described shutoff valve based on the volume of gas formed in the fuel chamber or the volume of the space formed above the fuel interface, instead of the highest level of the fuel interface.

Further, the evaporative fuel discharge action may be controlled based on determining whether the level of the fuel interface is higher than the predetermined level or determining whether the amount of gas in the fuel chamber is larger than the predetermined amount. Of course, in the above embodiment, it is determined whether a predetermined gas exists in the fuel chamber when the level sensor is in the off state.

While the invention has been described with reference to specific embodiments selected for purposes of illustration, it will be apparent to those skilled in the art that various modifications may be made without departing from the basic concept and scope of the invention.

Claims (15)

A fuel storage device for storing fuel therein, A partition wall that divides an interior of the fuel storage device into a fuel chamber and an air chamber, and which is deformable according to the amount of fuel in the fuel chamber; A discharge passage open to a space formed above the fuel interface in the fuel chamber; A shutoff valve for blocking the discharge passage; Gas discharge means for discharging gas from the space via the discharge passage when the shutoff valve is opened; When the amount of gas is greater than the predetermined amount, the gas discharge means is operated to discharge the gas from the space and controls the gas discharge means and the shutoff valve to open the shutoff valve, and the gas amount is less than the predetermined amount. And control means for stopping the operation of the gas discharging means and closing the shutoff valve when stopping the discharging action of the gas. A fuel interface level detecting means is provided for detecting the level of the fuel interface in the fuel chamber, wherein the control means is such that the level of the fuel interface detected by the fuel interface level detecting means is lower than a predetermined level. And when the amount of gas is determined to be lower than the predetermined amount. 2. A fuel interface level raising means is provided for elevating the level of the fuel interface, wherein the gas discharging means is adapted to discharge the gas from the space when the amount of gas is greater than the predetermined amount. And a fuel storage device for controlling the fuel interface level raising means to raise the level. 4. The fuel storage device according to claim 3, wherein the fuel interface level raising means supplies fuel to the fuel chamber to raise the level of the fuel interface. 4. The fuel storage device according to claim 3, wherein the fuel interface level raising means deforms the dividing wall to raise the level of the fuel interface. 6. The fuel storage device of claim 5, wherein the fuel interface level raising means increases the pressure in the air chamber to deform the partition wall. 7. The fuel storage device according to claim 6, wherein the fuel interface level raising means increases the pressure in the air chamber to a pressure lower than the pressure of the fuel supplied to the fuel chamber when the fuel is supplied to the fuel chamber. 7. The fuel storage device according to claim 6, wherein the fuel interface level raising means reduces the pressure in the air chamber when the supply of fuel to the fuel chamber is stopped. 6. The fuel storage device according to claim 5, wherein the fuel interface level raising means introduces a negative pressure into the space to deform the partition wall. 10. The fuel storage device according to claim 9, wherein the fuel interface level raising means includes a fuel pump for pumping fuel such that negative pressure is generated by the pumped fuel, and introduces the negative pressure into the space via the discharge passage. 11. The fuel storage device of claim 10, wherein the fuel interface level raising means returns a portion of the fuel pumped by the fuel pump into the fuel chamber so that a negative pressure is generated. 11. The fuel pump of claim 10, wherein the fuel pump is mounted in a pump chamber connected to the fuel chamber, and the fuel interface level raising means returns a portion of the fuel pumped by the fuel pump into the pump chamber so that a negative pressure is generated, A fuel storage device for introducing a negative pressure into the space formed above the fuel interface in the pump chamber. The fuel storage device of claim 9, wherein the discharge passage is connected to an intake system of an engine, and the fuel interface level raising means introduces a negative pressure in the intake system into a space formed above the fuel interface via the discharge passage. 15. The system of claim 13, wherein the discharge passage is connected to the intake system via a canister that adsorbs evaporated fuel, the canister into the atmosphere when the pressure in the canister is below a negative pressure predetermined to communicate the canister with the atmosphere. A fuel storage device having a valve that opens. 14. The fuel storage device according to claim 13, wherein the fuel interface level raising means raises the level of the fuel interface when the engine is capable of receiving evaporated fuel.