JP6399278B2 - Vehicle fuel tank system - Google Patents

Description

  The present invention relates to a fuel tank device for a vehicle, and more particularly to an improvement in a fuel tank device in which a fuel pipe, a recirculation pipe, and the like are provided in a fuel tank sealed by a sealing means.

  In a fuel tank device of a vehicle, a fuel pipe that supplies fuel to a fuel tank that stores fuel, or a pipe that communicates the upper space in the fuel tank with the fuel inlet side of the fuel pipe, that is, fuel supply when fueling is used. A recirculation pipe that prevents the vaporized gas (evaporated fuel) in the fuel tank from being released into the atmosphere is provided (see Patent Document 1).

JP2013-19281A

However, in the fuel tank device of the vehicle, it is conceivable that the fuel cap that suddenly closes the fuel supply port of the fuel pipe is removed from the state of the high-pressure fuel tank, and the oil supply port is opened.
In this case, when the recirculation pipe opens to the upper space of the fuel level in the fuel tank, only the vaporized gas is discharged from the fuel filler through the recirculation pipe. However, when the fuel is filled to the vicinity of the full tank position of the fuel tank, the opening on the tip side of the recirculation pipe may be immersed in the fuel in the fuel tank. In this case, the pressure in the fuel tank is applied to the liquid level of the fuel, the fuel in the fuel tank is pushed out to the recirculation pipe, and may leak to the outside through the circulation pipe from the opened fuel supply port. This fuel leakage occurs when the fuel cap is opened by an external operation, for example, in an unintended situation, such as when the fuel lid fails or the fuel lid is intentionally opened. To happen. Therefore, there is a demand for a means for preventing fuel leakage under such unexpected circumstances.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a fuel tank device for a vehicle that can prevent fuel from leaking from a fuel filler port under unexpected circumstances.

According to the first aspect of the present invention, there is provided a fuel pipe that communicates between the fuel filler port that is releasably closed by the fuel cap and the inside of the fuel tank, and a rear pipe that communicates the upper space in the fuel tank and the fuel inlet side of the fuel pipe. Circulation pipe, shutoff valve that is provided in the fuel pipe to prevent the fuel in the fuel tank from flowing back to the fuel pipe, and the liquid level in the fuel tank is closed at the full tank position. It has a leveling valve to be valved and a flow restriction valve that is provided in the recirculation pipe and closes at a position immediately below the full tank position of the liquid level in the fuel tank .

According to a second aspect of the present invention, in the fuel tank device for a vehicle according to the first aspect , the flow regulating valve is in a closed state when at least the fuel is filled to a position immediately below the full tank position. It was decided to consist of float valves.
According to a third aspect of the present invention, in the fuel tank device for a vehicle according to the first or second aspect , a canister that adsorbs the vaporized gas in the fuel tank, a passage that connects the fuel tank and the canister, provided in the passage, and a sealing valve for sealing the fuel tank by blocking the passage, opening of the fuel tank side of the through passage so as to be located at the top than the fuel tank side opening of the recirculation pipe Configured.

According to the present invention, failure or the fuel lid, such as when or intentional fuel lid is opened, even as the filler opening in the context of unintended unexpected is opened, the fuel in the fuel tank However, it does not leak to the outside through the recirculation pipe.

Therefore, leakage of fuel from the fuel filler port under unexpected circumstances can be prevented .

According to the invention of claim 2 , since the flow regulating valve is constituted by a float valve, a simple structure is sufficient.
According to the invention of claim 3 , even when the sealing valve for sealing the fuel tank is opened, the backflow of the fuel can be prevented.

The figure which shows schematic structure of the fuel tank apparatus of the vehicle which concerns on one Embodiment of this invention with peripheral apparatus. Sectional drawing which shows the structure of the distribution control valve | bulb of the fuel tank apparatus with an open state. Sectional drawing which shows the state which the same distribution control valve closed. Sectional drawing explaining the condition when a fuel cap is removed and the fuel filler opening was opened unexpectedly.

Hereinafter, the present invention will be described based on an embodiment shown in FIGS.
FIG. 1 shows a schematic configuration of a fuel tank device used in a vehicle to which the present invention is applied, for example, a hybrid vehicle in which a driving motor and an engine are combined. FIGS. 2 and 3 are flow control valves of the fuel tank device. This shows the structure and operation.
The fuel tank apparatus shown in FIG. 1 will be described. 1 is a reciprocating engine (hereinafter simply referred to as an engine), 10 is a fuel tank that stores fuel (liquid fuel such as gasoline), and 32 is a vaporized gas (in the same fuel tank 10). A purge passage 50 for passing the vaporized fuel for purging the evaporated fuel) by the engine, and 50, a dedicated canister for adsorbing the vaporized gas during refueling.

Explaining each part, the engine 1 combined with the traveling motor has an intake manifold 2, a surge tank 3, a throttle valve 4, an air cleaner 5 and the like on the intake side (all of which constitute an intake passage of the engine 1). . A fuel injector 6 is attached to the intake manifold 2.
The fuel tank 10 is formed by a flat tank, for example. The top of the fuel tank 10, and the fuel cut valve 11, etc. in the bulb 11 two-way valve 12 leveling valve 1 3 connected via is disposed.

The leveling valve 13 is constituted by, for example, a float valve that closes as the fuel level rises. When the fuel level is below the leveling valve 13 during refueling, the leveling valve 13 is closer to the fuel level in the fuel tank 10. It functions so that fuel can be supplied by discharging the upper vaporized gas toward a vapor passage 31 described later. Further, when the fuel rises to the liquid level indicated by the alternate long and short dash line in FIG. 1, the fuel is closed to prevent the vaporized gas above the liquid level of the fuel tank 10 from flowing into the vapor passage 31 described later. The tank 10 has a function of blocking the outflow destination of the vaporized gas, creating a situation in which new fuel is difficult to flow in from a fuel filler port 20 described later, and regulating the full tank position of the fuel tank 10. Here, for example, the position where the leveling valve 13 closes at the liquid level in the fuel tank 10 is the full tank position δ .

  A fuel pump 15 is installed at the bottom of the fuel tank 10. The fuel passage 14 extending from the discharge portion of the fuel pump 15 is connected to the fuel injector 6 so that the fuel in the fuel tank 10 is supplied from the fuel injector 6 to a combustion chamber (not shown) of the engine 1. Yes. Note that the return path from the fuel injector 6 to the fuel tank 10 is not shown. Alternatively, a pressure regulator (not shown) may be attached to the components of the fuel pump 15 in the fuel tank 10 to form a return path in the fuel tank 10.

  Further, a fuel pipe 17 and a recirculation pipe 18 are provided on the side wall of the fuel tank 10. Of these, the end of the fuel pipe 17 on the outlet side is connected to the middle of the side wall of the fuel tank 10, for example. A shut-off valve 16 composed of a check valve is provided at the end on the outlet side to prevent the fuel in the fuel tank 10 from flowing back to the fuel pipe 17. Further, the end of the fuel pipe 17 on the inlet side continues to a point above the position of the fuel tank 10, for example, a fuel box 19 provided at the same point. The end portion on the inlet side communicates with a fuel filler port 20 disposed in the fuel box 19 and communicates between the fuel filler port 20 and the inside of the fuel tank 10.

  The fuel filler opening 20 is closed with a fuel cap 21 so as to be openable, and the opening of the fuel box 19 is closed with, for example, a rotating fuel lid 23. The fuel lid 23 is normally locked so that it can be released by a lid actuator 22. That is, the lock is released, the fuel lid 23 is opened, then the fuel cap 21 is opened, and the fuel filler port 20 is opened, whereby a fuel gun (none of which is not shown) of the fuel filler is inserted into the fuel filler port 20 and fueled. By operating the gun, the fuel tank 10 can be refueled. Incidentally, a pressure sensor 24 for detecting the internal pressure of the fuel tank 10 is provided on the upper wall of the fuel tank 10.

  An end 18 a on the outlet side of the recirculation pipe 18 is connected to a position near the fuel filler port 20 of the fuel pipe 17. Further, the end 18 b on the inlet side of the recirculation pipe 18 passes through the upper stage of the side wall of the fuel tank 10. This end 18 b extends to the vicinity of the full tank position δ defined by the leveling valve 13. In the path of the recirculation pipe 18, for example, a float valve 26 is provided at the inlet end of the recirculation pipe 18 as a flow regulating valve. Details of the float valve 26 will be described later.

  On the other hand, the canister 50 is composed of a container containing activated carbon (not shown). In this container, a module for performing a leak check in the fuel tank 10 at a predetermined time set in advance using a pressure sensor 24 or a sealing valve 35 described later, such as a negative pressure pump (not shown), A leak check module 51 including a vent pipe 53 that opens to the atmosphere, a negative pressure pump, and a switching valve (not shown) that switches communication of the vent pipe 53 is mounted. The vent pipe 53 is provided with a filter 55.

  The vaporized gas processing unit 30 for purging the evaporated gas by the engine includes, for example, a vapor passage 31 (corresponding to the passage of the present application) that communicates between the leveling valve 13 and the inlet / outlet on the vaporized gas side of the canister 50. A purge passage 32 that connects the end of the passage 31 on the inlet / outlet side and the intake passage of the engine 1, for example, the intake passage portion between the surge tank 3 and the throttle valve 4, provided in each part of these passages 31, 32, for example A normally-closed sealing valve 35, a barge valve 36, a normally-open canister valve 37, and a control unit 38 (for example, an electronic unit composed of a CPU, ROM, RAM, etc.) for controlling these valves are combined. .

  That is, the sealing valve 35 is provided together with the bidirectional safety valve 40 in the middle of the vapor passage 31 that communicates the inside of the fuel tank 10 and the canister 50. The purge valve 36 is provided in the middle of the purge passage 32, and the canister valve 37 is provided at the inlet / outlet of the canister 50 on the vaporized gas side. And by the characteristic of each valve, it constitutes a sealed system that seals the inside of the fuel tank 10 under normal conditions, keeps the closed space in the fuel tank 10 sealed in the normal condition, and the vaporized gas in the fuel tank 10 The fuel tank 10 is prevented from leaking out. The leak check in the fuel tank 10 is performed from this sealed state.

  In order to process the vaporized gas in the fuel tank 10, the control unit 38 opens the barge valve 36 and the sealing valve 35, for example, when the engine 1 is operated under predetermined conditions, and sets the canister valve 37. The function to close is set. With this function, the vaporized gas in the fuel tank 1 is purged to the intake passage of the engine 1 during operation through the fuel cut valve 11, the leveling valve 13, the vapor passage 31, and the purge passage 32, and is processed (combusted) in the engine 1. To be.

  For example, in order to supply the fuel, the control unit 38 operates the lid switch 39 to release the lock of the fuel lid 23, and opens the sealing valve 35, and the vaporized gas in the fuel tank 10 is changed to the fuel cut valve 11, It is guided to the canister 50 through the leveling valve 13, the vapor passage 31, and the canister valve 37. That is, by operating the lid switch 39, the vaporized gas is adsorbed, and the pressure in the fuel tank 10 is removed to a safe pressure at which the fuel tank 10 can be refueled while preventing the vaporized gas from being released into the atmosphere. .

  Further, when the pressure in the fuel tank 10 is sufficiently reduced by the opening operation of the sealing valve 35 (safe pressure: equivalent to the atmospheric pressure), the control unit 38 prevents the release of the vaporized gas during refueling. A function for opening the lid 23 (unlocking by the lid actuator 22) is set. Thus, after decompression, the fuel lid 23 is opened, the fuel cap 21 is further removed, and the fueling gun of the fueling device is inserted into the opened fueling port 20, and the fueling operation is performed with the fueling gun. The vaporized gas in the space above the liquid level in the tank 10 is guided to the end 18b, the recirculation pipe 18, and the end 18a as indicated by the arrow in FIG. The recirculation pipe 18 and the fuel pipe 17 are circulated by repeating the circulation cycle of being led into the pipe 10. Also at this time, since the sealing valve 35 and the canister valve 37 are opened (the purge valve 36 is closed), the vaporized gas in the fuel tank 10 is guided to the canister 50.

  Due to the circulation of the vaporized gas and the adsorption of the vaporized gas by the canister 50, the vaporized gas in the fuel tank 10 can be prevented from being released to the outside from the fuel filler port 20 during refueling. Incidentally, the vaporized gas adsorbed by the canister 50 is purged to the intake passage of the engine 1 through the purge passage 32 and the purge valve 35 when the engine 1 is operated under the control of the control unit 38 (processing by combustion).

  On the other hand, the float valve 26 in the recirculation pipe 18 does not remove the fuel cap 21 through a normal procedure, but when the fuel cap 21 is removed at an unexpected time, that is, the pressure in the fuel tank 10. When the fuel pressure exceeds the head pressure at the fuel filler port 20 and the fuel is filled up to the vicinity of the full tank position, the fuel filler 21 is taken into consideration when an unintended and unexpected situation occurs. This is a device that prevents fuel from leaking from 20. As an unexpected situation, the fuel cap 21 is removed and the fuel filler opening 20 is opened due to a failure of the fuel lid 23, or the fuel lid 23 is intentionally opened, the fuel cap 21 is removed, and the fuel filler opening 20 is opened. The case where it is done is considered.

2 and 3 show a specific structure of the float valve 26 (part A) provided for this unexpected situation.
Referring to each part of the float valve 26, reference numeral 60 in FIGS. 2 and 3 denotes, for example, a valve main body formed of a vertical bottomed cylinder with the opening facing downward, and 61 denotes the valve main body 60. A float guide 62 formed of a vertical cylindrical member provided inside is a valve having a valve hole 64 and a valve seat 65 provided so as to block between the float guide 61 and the upper wall 60a of the valve body 60. It is a seat member. With this structure, a cylindrical flow path 67 is formed between the side wall 60 b of the valve body 60 and the float guide 61. The channel 67 communicates between the annular inlet 69 formed at the lower end of the valve body 60 and the valve hole 64. A relay chamber 70 is formed between the valve seat member 62 and the upper wall 60 a, and a float chamber 71 is formed in the float guide 61.

  And the side wall part of the relay chamber 70 is connected in communication with the end 18b of the circulation pipe 18, and supports the valve body 60 in the vertical direction. In the float chamber 71, a float 73 having a valve portion 72 assembled at the upper portion is accommodated so as to be movable up and down. As a result, the float 73 follows the fuel level in the fuel tank 10, and the valve portion 72 and the valve seat 65 come into contact with each other to close the valve hole 64 to close the valve hole 64 (FIG. 3). 72 and the valve seat 65 move up and down between a standby position Y (FIG. 2) where the valve hole 64 is opened by separating.

  The float valve 26 has various parts set so that the path of the circulation pipe 18 is closed when the fuel tank 10 is near the full tank position δ, for example, when the fuel is filled to a position immediately below the full tank position δ. Yes. Specifically, the valve hole 64 is defined at a position above the full tank position δ. In other words, the opening of the vapor passage 31 on the fuel tank 10 side is positioned above the opening of the circulation pipe 18 on the fuel tank 10 side. Further, each part of the valve part 72 is determined so that when the fuel is filled up to a position immediately below the full tank position δ, the valve hole 64 is blocked by the rising float 73 and the path of the circulation pipe 18 is blocked. Thereafter, the fuel flow regulation is continued until the fuel level drops from the full tank position δ. That is, the float valve 26 moves the float 73 until the leveling valve 13 is closed when the liquid level in the fuel tank 10 rises and at least the fuel is filled to the full tank position δ defined by the leveling valve 13. Thus, the valve hole 64 is closed and the path of the circulation pipe 18 is blocked.

Next, preparation for an unexpected situation of the fuel tank 10 will be described with reference to FIG.
Now, suppose that the vehicle is parked, for example, the fuel tank 10 is filled with fuel up to near the full tank position δ, and the fuel tank 1 is sealed in a high pressure state.
At this time, for example, due to intention or failure of the lid actuator 22, the fuel lid 23 is opened manually and the fuel cap 21 in the fuel box 19 is opened as shown in FIG. Suppose something happens.

  At this time, if the internal pressure of the fuel tank 10 is a pressure that exceeds the head pressure of the fuel filler port 20, the outlet of the fuel pipe 17 is blocked by the shut-off cut 16. Due to the internal pressure, the fuel in the fuel tank 10 is pushed into the circulation pipe 18 from the end of the circulation pipe 18 that is submerged in the fuel, and leaks from the fuel filler port 20 to the outside through the circulation pipe 18. Although there is a risk that it will come out, since the float valve 26 is provided in the path of the circulation pipe 18, such a situation does not occur.

  That is, the inlet end of the circulation pipe 18 is already blocked by the valve portion (the valve portion 72 and the valve hole 64) of the float valve 26 from the time when the fuel is stored near the full position δ (FIG. 3). The fuel is prevented from flowing through the circulation pipe 18. For this reason, even if it is a case where the internal pressure of the fuel tank 10 is high exceeding the head pressure of the fuel filler opening 20, the fuel in the fuel tank 10 leaks from the fuel filler opening 20 to the outside through the recirculation pipe 18. It does not lead to.

Therefore, leakage of fuel from the fuel filler opening 20 under unexpected circumstances can be prevented.
In addition, the flow regulation by the float valve 26 starts when the fuel level in the fuel tank 10 is located immediately below the full tank position δ, and is not released unless the liquid level falls below the full tank position δ. In addition to dealing with fuel leakage from the fuel filler port 20, the fuel tank 10 can be prevented from being supercharged, and the amount of transpiration gas released from the fuel filler port 20 through the recirculation pipe 18 during and after fueling (refueling) The reduction of the amount of HC released later) and the securing of the amount of vaporized gas that circulates from the recirculation pipe 18 to the fuel pipe 15 during refueling (reduction of the capacity of the canister 50) can be sufficiently achieved.

  Further, by preventing supercharging, it is possible to prevent the opening of the purge passage 31 connected to the sealing valve 35 at a position higher than the opening of the recirculation pipe on the fuel tank 10 side from being submerged. Even when the pressure is unintentionally opened and the pressure in the fuel tank 10 is suddenly reduced, backflow of fuel toward the sealing valve 35 is prevented, and fuel can be prevented from being ejected to the canister 50 side.

In particular, the float valve 26 having such an effect is a valve that operates without receiving a control command from the outside, so that a simple structure that does not require peripheral devices is sufficient.
The present invention is not limited to one embodiment, and various changes may be made without departing from the spirit of the present invention. For example, in the above-described embodiment, the float valve is exemplified as the flow regulating valve. However, the present invention is not limited to this, and other valves may be used. When the fuel in the fuel tank is filled to the full tank position, the recirculation valve is used. Any valve may be used as long as it blocks the inside of the pipe. Of course, the float valve may be at any position as long as it is a path of the recirculation pipe.

10 fuel tank 13 leveling valves 16 shut-off valve 17 Fuel pipe 18 recirculation pipe 20 the fuel supply port 26 float valve (flow control valve)
31 Vapor passage (passage)
35 Sealing valve 50 Canister δ Full tank position

Claims (3)

A fuel tank for storing fuel;
A fuel pipe that communicates between a fuel filler port that is releasably closed by a fuel cap and the inside of the fuel tank;
A recirculation pipe communicating the upper space in the fuel tank and the fuel inlet side of the fuel pipe;
A shut-off valve that is provided in the fuel pipe and suppresses the fuel in the fuel tank from flowing back to the fuel pipe;
A leveling valve disposed at an upper portion in the fuel tank and closing a liquid level in the fuel tank at a full tank position;
A fuel tank device for a vehicle, comprising: a flow regulating valve provided in the recirculation pipe and closing a liquid level in the fuel tank at a position immediately below the full tank position . The fuel tank apparatus for a vehicle according to claim 1 ,
The vehicle fuel tank apparatus according to claim 1, wherein the flow regulating valve is a float valve that is closed when at least the fuel is filled to a position immediately below a full tank position. The fuel tank device for a vehicle according to claim 1 or 2 ,
A canister that adsorbs the transpiration gas in the fuel tank;
A passage communicating the fuel tank and the canister;
A sealing valve that is provided in the passage and seals the fuel tank by sealing the passage;
The fuel tank device for a vehicle according to claim 1, wherein the fuel tank side opening of the passage is located above the fuel tank side opening of the recirculation pipe.

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