JP6183605B2 - Vehicle fuel system - Google Patents

Description

  The present invention relates to a fuel device for a vehicle that can suppress erroneous determination of pressure in a fuel tank.

In a fuel device for a vehicle, particularly a vehicle such as a hybrid vehicle in which a driving motor and an engine are combined, where there is little opportunity to operate the engine, in order to suppress the evaporation of the fuel vapor in the fuel tank to the atmosphere, Adopting a sealing system to prevent the evaporation gas from leaking out of the fuel tank.
In the closed system, the evaporative gas in the fuel tank is processed (burned) using the opportunity of engine operation, but the operation of the engine is stopped during refueling, so the evaporative gas cannot be processed. For this reason, the fuel device of the closed system uses a canister as a countermeasure when refueling. Specifically, the leveling valve provided in the fuel tank communicates with the caster via a vapor passage, and a sealing valve is provided in the vapor passage so that the fuel tank is sealed or the fuel is released by opening the sealing valve. The evaporated gas in the tank is adsorbed by the canister (Patent Document 1).

In such a sealing system, the pressure sensor monitors the pressure in the fuel tank and controls each part of the sealing system. The pressure sensor is provided in the fuel tank as shown in Patent Document 1, but usually only one (Patent Document 1).
However, if only one pressure sensor is used, the pressure in the fuel tank cannot be detected at all if the pressure sensor becomes abnormal.

For this reason, it is conceivable to provide a circuit for detecting an abnormality of the pressure sensor. However, the circuit for determining whether or not the pressure sensor is abnormal tends to be quite complicated, and the cost is considerably increased.
Therefore, the present applicant provides two pressure sensors at different positions of the fuel tank, detects the pressure in the fuel tank from the detected pressures of the two pressure sensors, or when the pressure in the fuel tank fluctuates to a predetermined level. We have applied for a technology that mutually monitors the pressure detected by the two pressure sensors and detects an abnormality in the pressure sensor from the monitored results. According to this technology, not only two pressure sensors are sufficiently provided for sensor abnormality, but also abnormality detection of the pressure sensor can be performed at low cost.

JP2013-92135A

  Mutual monitoring by the two pressure sensors is fully demonstrated when the inside of the fuel tank is sealed with the sealing valve, but the sealing valve is opened when the leveling valve is immersed in the fuel level. If it is done, it is susceptible to the pressure fluctuation at that time. Specifically, when the leveling valve is submerged, if the sealing valve is opened, the pressure suddenly attenuates in the area from the leveling valve to the canister, and the pressure gradually attenuates in the area above the fuel level. Or

For this reason, the mutual monitoring of the two pressure sensors, when encountered at this time, erroneously determines that the detected pressures of the two pressure sensors have deviated and that the pressure sensor is normal but is abnormal. There is a risk that.
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a vehicle fuel device capable of continuing mutual monitoring by two pressure sensors without erroneous determination.

  According to the first aspect of the present invention, there is provided a fuel tank for storing fuel, a first pressure sensor and a second pressure sensor for detecting pressure in the fuel tank from different positions in the fuel tank, and a first pressure. A mutual monitoring unit for mutually monitoring the detected pressure output from the sensor and the second pressure sensor, a canister for adsorbing fuel evaporative gas generated in the fuel tank, and a fuel tank provided with fuel in the fuel tank A leveling valve that regulates fuel supply, a first vapor passage that communicates the leveling valve and the canister, guides the evaporative gas in the fuel tank to the canister, and the first vapor passage is normally sealed to the inside of the fuel tank. A sealing valve that seals the leveling valve, a dip detection unit that detects immersing of the leveling valve into the fuel level when the sealing valve is open, and a dip in the leveling valve is detected. Once it was assumed to have a monitoring prohibition unit that prohibits the mutual monitoring of mutual monitoring unit.

  According to a second aspect of the present invention, the fuel tank communicates a fuel cut-off valve that regulates the liquid level of the fuel tank at a liquid level higher than the leveling valve, a fuel cut-off valve, and the leveling valve. A second vapor passage that guides the evaporated gas to the canister via the leveling valve, and one of the first pressure sensor and the second pressure sensor is provided in the first vapor passage portion between the leveling valve and the sealing valve. The other is provided in the fuel tank, and the immersion detection unit is configured to determine whether the leveling valve is immersed in the fuel level based on fluctuations in the detected pressure of the first pressure sensor and the second pressure sensor. It was supposed to be.

  According to a third aspect of the present invention, the mutual monitoring unit compares the detection result of the first pressure sensor with the detection result of the second pressure sensor, and the first pressure sensor or the second pressure sensor based on the comparison result. Is configured to include a determination unit that determines that is abnormal.

According to the invention of claim 1, the two pressure sensors are not mutually monitored when the sealing valve is opened when the leveling valve is submerged, which is likely to cause an erroneous determination.
Therefore, mutual monitoring by the two pressure sensors can be continued without malfunction, and the sealed system can always be controlled satisfactorily.
According to the second aspect of the present invention, the structure in which the first and second pressure sensors are provided in the first vapor passage portion and the fuel tank is easy to detect the liquid immersion of the leveling valve. It is effective in avoiding monitoring.

  According to the invention of claim 3, the first and second pressure sensors can be mutually monitored with a simple logic.

The figure which shows schematic structure of the fuel apparatus of the vehicle used as the aspect which concerns on one Embodiment of this invention. The flowchart which shows the outline of the control which prohibits the mutual monitoring of a pressure sensor when a leveling valve is immersed. The diagram explaining the behavior of the first pressure sensor and the second pressure sensor when the leveling valve is exposed from the fuel liquid level. The diagram explaining the behavior of the first pressure sensor and the second pressure sensor when the leveling valve is immersed in the fuel liquid level. The diagram explaining the principle of mutual monitoring of the 1st pressure sensor and the 2nd pressure sensor performed after the exposure judgment of a leveling valve. The flowchart which shows roughly the control performed by the mutual monitoring of a 1st pressure sensor and a 2nd pressure sensor.

Hereinafter, the present invention will be described based on an embodiment shown in FIGS.
FIG. 1 shows a schematic configuration of a fuel device used in a vehicle to which the present invention is applied, for example, a hybrid vehicle combining a driving motor and an engine, and FIGS. 2 and 6 show control in the fuel device.
1, 1 is a reciprocating engine, 10 is a fuel tank that stores fuel (liquid fuel such as gasoline), 30 is an evaporative gas processing unit that processes evaporative gas in the fuel tank 10, and 50. Indicates a dedicated canister (during refueling) installed in the evaporative gas processing unit 30.

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. A fuel injector 6 is attached to the intake manifold 2.
The fuel tank 10 is formed by a flat tank, for example. In the upper part of the fuel tank 10, a fuel cutoff valve 11 (for example, a float valve), a vapor passage 12 having the fuel cutoff valve 11 and a two-way valve 12a (corresponding to the second vapor passage of the present application) A leveling valve 13 (for example, composed of a float valve) connected in series is disposed through the. The opening at the lower portion of the leveling valve 13 (the opening portion closed by the fuel liquid level) is positioned at a full tank position of the fuel stored in the fuel tank 10. That is, when refueling is started from the refueling port 20, the liquid level in the fuel tank 10 rises while expelling the vaporized gas in the fuel tank 10 from the leveling valve 13 to the canister 50. When the liquid level in the fuel tank 10 rises, the float valve provided in the leveling valve 13 rises and the opening is closed by the float valve. As a result, the amount of oil supply is regulated by blocking the air outlet in the fuel tank 10. The opening at the lower part of the fuel cut-off valve 11 (opening portion closed by the fuel liquid level) is positioned at a position higher than the leveling valve 13, and after the full tank position of the fuel tank 10 is regulated by the leveling valve 13. Even so, it is possible to prevent the vaporized gas in the fuel tank 10 from becoming a high pressure due to a small amount of the vaporized gas in the fuel tank 10 passing through the cut-off valve 11, thereby preventing the pressure in the fuel tank 10 from rising excessively. However, the fuel cut-off valve 11 prevents the liquid level in the fuel tank 10 from exceeding the full tank position regulation and entering the vapor passage 12 while the vehicle is running or when the vehicle rolls over. Yes.

  A fuel pump 15 is installed at the bottom of the fuel tank 10. The fuel passage 14 extending from the discharge part of the fuel pump 15 is connected to the fuel injector 6, and the fuel in the fuel tank 10 is supplied from the fuel injector 6 to a combustion chamber (not shown) of the engine 1. A return path from the fuel injector 6 back to the fuel tank 10 is not shown.

  A fuel pipe 17 and a recirculation pipe 18 for refueling are provided on the side wall of the fuel tank 10. The outlet side of the fuel pipe 17 is connected to, for example, the middle stage of the side wall of the fuel tank 10, and the inlet side of the fuel pipe 17 is connected to a fuel box 19 provided at a point above the position of the fuel tank 10, A fuel filler 20 is configured. The fuel filler opening 20 is closed by a fuel cap 21 so as to be opened and closed. Further, the opening of the fuel box 19 is closed by a rotating fuel door 23. The fuel door 23 is locked by the door actuator 22, and when the lock is released and the fuel cap 21 is opened, fuel can be supplied from the fuel supply port 20 to the fuel tank 10 using a fuel supply gun (not shown).

One end of the recirculation pipe 18 is connected in communication with the vicinity of the fuel filler opening 20 of the fuel pipe 17. The other end of the recirculation pipe 18 passes through the upper stage of the side wall of the fuel tank 10 and is disposed at a position slightly lower than the full tank position defined by the leveling valve 13.
A pressure sensor 24 (corresponding to, for example, the second pressure sensor of the present application) for detecting the internal pressure of the fuel tank 10 is provided on the upper wall of the fuel tank 10. Incidentally, as the pressure sensor 24, a sensor having a narrow area and high-precision characteristics is used.

  The canister 50 is equipped with a leak check module 51 which is mainly used for performing a leak check in the fuel tank 10. Specifically, the canister 50 is composed of a container containing activated carbon (not shown). Although not shown in the figure, this container has two entrances, an entrance on the evaporative gas side and an entrance on the atmosphere side. Of these, a leak check module 51 is provided at the air-side entrance / exit. The leak check module 51 is formed by modularizing, for example, a negative pressure pump 52, a vent pipe 53 that opens to the atmosphere, a negative pressure pump 52, and a switching valve 54 that switches communication of the vent pipe 53. Incidentally, the vent pipe 53 is provided with a filter 55.

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

  Specifically, the sealing valve 35 is provided along with the bidirectional safety valve 40 in the middle of the vapor passage 31. The purge valve 36 is provided in the middle of the purge passage 32, and the canister valve 37 is provided at the evaporative gas side inlet / outlet of the canister 50. Further, a pressure sensor 33 (corresponding to, for example, the first pressure sensor of the present application) for detecting the pressure in the fuel tank 10 is provided in a vapor passage portion between the leveling valve 13 and the sealing valve 35. Since the vapor passage portion is a portion where the pressure easily fluctuates in a wide range, a sensor having a wide range and low accuracy characteristics different from the characteristics of the pressure sensor 24 is used for the pressure sensor 33. These pressure sensors 24 and 33 having different characteristics at different positions are used to effectively detect the pressure in the fuel tank 10 while reducing costs.

  And the sealing system which seals the inside of the fuel tank 10 under normal conditions is comprised by the characteristic of each valve. Specifically, in the normal state, the fuel includes a space from the liquid level in the fuel tank 10 to an upper space, a purge passage part closed by the sealing valve 35, and a fuel pipe part closed by the fuel cap 21. The closed space in the tank 10 is kept sealed. Thus, the evaporated gas in the fuel tank 10 (the gas from which the fuel has evaporated) is prevented from leaking out of the fuel tank 10.

  In order to process the evaporated gas in the fuel tank 10 by the operation of the engine 1, the control unit 38 opens the purge valve 36 and the sealing valve 35, for example, when the engine 1 is operated under a predetermined condition. A function for closing the canister valve 37 is set. That is, the evaporated gas in the fuel tank 10 is purged from the fuel cut-off valve 11 and the leveling valve 13 to the intake passage of the operating engine 1 through the vapor passage 31 and the purge passage 32 and burned in the engine 1.

  In addition, the control unit 38 is set with a function to prevent the evaporated gas in the fuel tank 10 from being released into the atmosphere from the fuel filler port 20 when refueling (a situation where the engine 1 is not operating). For example, when the fuel door switch 39 is operated to release the lock of the fuel door 23 for refueling, the sealing valve 35 is opened, and the switching valve 54 (leak check module 51) is switched to the atmosphere opening side. It is constituted by a function (the negative pressure pump 52 may be operated). That is, when the fuel is supplied, the sealed state of the fuel tank 10 is released, and as shown by the solid line arrow in FIG. 1, the evaporated gas in the fuel tank 10 flows from the fuel cutoff valve 11 and the leveling valve 13 to the vapor passage 31. Then, the gas is guided to the canister 50 through the canister valve 37, and the evaporated gas is adsorbed on the activated carbon, thereby preventing the evaporated gas from being discharged from the fuel filler port 20.

  During this refueling, the pressure in the fuel tank 10 is sufficient for the control unit 38 according to the pressure detected by the pressure sensors 24 and 33 in order to prevent the fuel from flowing out from the refueling port 20 (due to the increase in tank internal pressure). When the value is lowered, the function of operating the door actuator 22 to the unlocking side is set. That is, measures are taken to prevent the fuel door 23 from being opened unless the pressure in the fuel tank 10 is sufficiently reduced.

Further, the control unit 38 has a liquid immersion function (immersion of the present application) for determining whether the leveling valve 13 is exposed from the fuel liquid level or is immersed (liquid immersion) when the sealing valve 35 is opened. Equivalent to the detection unit), a door non-opening function for opening the fuel door 23 using the determination result, and a notification function for notifying the occurrence of liquid immersion are set.
For the submergence determination, a technique using the pressure in the vapor passage portion between the leveling valve 13 and the sealing valve 35 and the pressure in the upper space of the fuel surface of the fuel tank 10 is used so that sufficient results can be obtained. .

  That is, the method for determining the liquid immersion will be described. When the sealing valve 35 is opened from the state in which the leveling valve 13 is exposed from the fuel liquid level, the evaporated gas in the fuel tank 10 is changed to the fuel cutoff valve 11. And the leveling valve 13 gradually escapes through the vapor passage 31, so that the pressure in the fuel tank 10 and the vapor passage 31 gradually behaves toward atmospheric pressure. In other words, the pressures detected by the pressure sensors 24 and 33 are both directed to the atmospheric pressure with slow pressure fluctuations.

  On the other hand, when the sealing valve 35 is opened from the state in which the leveling valve 13 is immersed in the fuel level, the portion between the fuel cutoff valve 11 and the leveling valve 13, that is, the vapor passage 12 and the two-way valve. 12a becomes a choke (throttle portion), and the pressure in the vapor passage portion immediately goes to the atmospheric pressure, but the pressure in the upper space of the fuel liquid level is different from this, and gradually increases as described above. Head to atmospheric pressure.

For this reason, the pressure sensor 33 for detecting the pressure in the fuel tank 10 is provided in the vapor passage portion between the leveling valve 13 and the sealing valve 35, thereby simply detecting the pressure of the fuel tank 10 together with the pressure sensor 24. In addition to this, it is possible to detect a sudden pressure fluctuation accompanying the liquid immersion of the leveling valve 13.
The control unit 38 has a function of determining whether the leveling valve 13 is submerged based on the detected pressure from the pressure sensors 24 and 33. For example, in the control unit 38, the pressure detected by the pressure sensor 33 is a fluctuation (absolute value) of most of an initial value, for example, 80% or more during a predetermined time after the sealing valve 35 is opened, and the pressure sensor 24. A function for determining whether or not there is a behavior in which the pressure gradually decreases, for example, whether or not there is an absolute value fluctuation within 20% of the initial value of the pressure sensor 24 is set. When these conditions are satisfied, it is determined that the leveling valve 13 is submerged (corresponding to the immersion detection unit of the present application). The determination by the two pressure sensors 24 and 33 ensures the liquid immersion determination.

  Further, when the control unit 38 determines that the leveling valve 13 is submerged, the control unit 38 restricts the opening of the fuel filler opening 20 by closing the sealing valve 35 and restricting the outflow of fuel, or by continuing to lock the door actuator 22. A function and a function for notifying the current state that the leveling valve 13 is submerged using the display device 38a (notification unit) are set to ensure safety.

Since the submergence determination and various functions are established only when there is no abnormality in the pressure sensors 24 and 33, the control unit 38 monitors the pressure sensor 24 and the pressure sensor 33 to each other, and A mutual monitoring function (corresponding to the mutual monitoring unit of the present application) for detecting the presence or absence of 33 abnormalities is set.
For the control of this function, for example, as shown in FIG. 6, when the leveling valve 13 is exposed and the sealing valve 35 is opened (normal state), each pressure sensor until the pressure is reduced to a predetermined pressure. Step S20 for calculating the inclinations of 24 and 33 (within the detection region of the pressure sensor 24), step S21 for comparing the inclinations (corresponding to the comparison unit of the present application), and a predetermined error range are determined as normal. If it is out of the range, a routine using step S22 (corresponding to the determination unit of the present application) that is determined to be abnormal is used.

Specifically, in the control unit 38, based on the following equation (1), the period Tn until the first tank internal pressure P1 in FIG. 5 detected by the pressure sensor 24 changes from the first predetermined pressure Pn1 to the second predetermined pressure Pn2. The change rate ΔPw at is calculated.
ΔPw = (Pn2−Pn1) / Tn (1)
When the first tank internal pressure P1 becomes the first predetermined pressure Pn1, the second tank internal pressure Pw1 at the first predetermined pressure Pn1, which is the second tank internal pressure P2 detected by the pressure sensor 33, and the first tank internal pressure P1 are When the second predetermined pressure Pn2 is reached, the second tank internal pressure Pw2 at the second predetermined pressure Pn2, which is the second tank internal pressure P2, and the first tank internal pressure P1 from the first predetermined pressure Pn1 to the second predetermined pressure Pn2 Based on the period Tn and the following equation (2), the rate of change ΔPn of the second tank internal pressure P2 detected by the pressure sensor 33 in the period Tn is calculated.

ΔPn = (Pw2−Pw1) / Tn (2)
By comparing the detection results of these pressure sensors 24 and 33, an error rate Er between the change rate ΔPw of the first tank internal pressure P1 and the change rate ΔPn of the second tank internal pressure P2 is calculated based on the following equation (3). An abnormality of the pressure sensor 24 or the pressure sensor 33 is detected by determining whether or not the obtained error rate Er is equal to or greater than a predetermined value (determination unit).

Er = | (ΔPw−ΔPn) / ΔPn | × 100 (3)
In FIG. 5, r1 indicates a measurable region of the pressure sensor 24, and r2 indicates a measurable region of the pressure sensor 33.
The abnormality detection of the pressure sensors 24 and 33 by mutual monitoring is related to normality when the detected pressure of the pressure sensor 33 largely fluctuates with respect to the other pressure sensor 24 as in the case where the leveling valve 13 is submerged. It is easy to cause an erroneous determination that it is determined as abnormal.

Therefore, in order to prevent such erroneous determination, the control unit 38 prohibits detection of the abnormality of the pressure sensors 24 and 33, that is, restricts the mutual monitoring from being performed when it is determined that the leveling valve 13 is submerged. Is set (corresponding to the monitoring prohibition unit of the present application).
FIG. 2 shows a flow chart schematically summarizing each control of such a fuel device. Referring to the flowchart, it is assumed that the fuel door switch 39 is turned on as shown in step S1 for refueling, for example.

Then, as shown in step S2, the sealing valve 35 is opened, and in the subsequent step S3, it is determined whether or not there is an abnormality in the pressure sensors 24 and 33 until the current refueling. In this determination, the abnormality determination result of the pressure sensors 24 and 33 until the current refueling is also taken into consideration.
If it is determined in step S3 that the pressure sensors 24 and 33 are not abnormal, the process proceeds to step S4. In step S4, after confirming that the pressure detected by the pressure sensors 24 and 33 is outside the measurement area of the pressure sensor 24 (+ α kPa or more and −α kPa or less), the sealing valve 35 is used as in step S5. The degree of pressure fluctuations in the vapor passage portion (first vapor passage) and the upper space of the fuel level of the fuel tank 10 generated after the opening of the fuel tank 10 is detected.

  That is, when the sealing valve 35 is opened, when the fuel level is below the leveling valve 13 as shown by the solid fuel level in FIG. The accumulated evaporative gas includes a route passing from the fuel cut-off valve 11 to the two-way valve 12a and the leveling valve 13 as shown by a solid line arrow in FIG. 1, and an evaporative gas from the fuel cut-off valve 11 from the leveling valve 13. The canal 50 is adsorbed by the canister 50 through the joining route. Therefore, the pressure in the fuel tank 10 detected by the pressure sensors 24 and 33 is attenuated in the same manner as shown in FIG.

On the other hand, when the fuel level is above the leveling valve 13 (immersion) as shown by the one-dot chain line in FIG. 1, the two-way valve 12a becomes a choke (throttle portion), Only the pressure after the sealing valve 35 from the leveling valve 13 detected by the pressure sensor 33 is attenuated immediately toward the atmospheric pressure.
In step S5, for example, a determination is made as to whether or not there is a rapid fluctuation in the pressure detected by the pressure sensor 33 within a predetermined time β (for example, 0.5 s) after the opening of the sealing valve 35 so as to capture this sudden pressure fluctuation. For example, in order to determine whether or not there is an absolute fluctuation of 80% or more of the initial value, and to clarify whether or not the pressure fluctuation occurs when the sealing valve 35 is opened, the pressure of the pressure sensor 24 is gradually attenuated. For example, a process for determining whether there is an absolute value fluctuation within 20% of the initial value is performed.

Here, if it is determined that there is no sudden and large pressure fluctuation (FIG. 3), it is determined that the leveling valve 13 is exposed from the fuel surface (step S6).
Then, in the subsequent step S7, mutual monitoring of the pressure sensor 24 and the pressure sensor 33 as shown in the flowchart of FIG. 6 is performed. This is because the slopes of the pressure sensors 24 and 33 at the time of attenuation are calculated, the slopes are compared, and if the results of the comparison are within a predetermined error range, the pressure sensors 24 and 33 are determined to be normal. If it is out of the range, the pressure sensor 24 or the pressure sensor 33 is performed in a routine for determining that it is abnormal (step S8).

If it is determined in step S8 that there is no abnormality, the process proceeds to step S9, the door actuator 22 is opened, and the fuel door 23 is "opened", allowing refueling. The “opening” of the fuel door 23 is performed after the pressure in the fuel tank 10 is sufficiently lowered although not shown.
If it is determined in step S5 that there is a rapid and large pressure fluctuation, the process proceeds to step S10, where it is determined that the leveling valve 13 is immersed in the fuel liquid level, that is, is submerged.

  In response to this result, the process proceeds to step S11, and the detection of the abnormality of the pressure sensor 33 based on the mutual monitoring of the pressure sensor 24 and the pressure sensor 33 is prohibited. Of course, until the safety is ensured as a result of the immersion of the leveling valve 13, the routine from step S3 to step S12 continues to "close" the fuel door 23 and the sealing valve 35 to reject the request for refueling. The display device 38a notifies the outside that the cause of the oil supply request refusal is submersion.

In this way, sensor abnormality detection by mutual monitoring is not performed when the sealing valve 35 is opened when the leveling valve 13 is submerged, so there is no possibility of erroneous determination. Therefore, sensor abnormality detection is continued well, and mutual monitoring with high accuracy can always be promised. Thereby, a sealed system can be maintained satisfactorily.
In particular, if the pressure sensors 24 and 33 are provided in the vapor passage 31 and the fuel tank 10, it is easy to detect liquid immersion in the leveling valve 13, which is effective in avoiding mutual monitoring of the pressure sensors 24 and 33.

Moreover, the mutual monitoring of the pressure sensors 24 and 33 is simple because the logic for comparing the detection results of the pressure sensors 24 and 33 to detect an abnormality is used.
Note that the present invention is not limited to the above-described embodiment, and various modifications may be made without departing from the spirit of the present invention. In one embodiment, a sealing system using a canister valve is described. However, the present invention is not limited to this, and a sealing system that does not use a canister valve may be used.

10 Fuel tank 11 Fuel cut-off valve 12 Vapor passage (second vapor passage)
13 Leveling valve 24 Pressure sensor (second pressure sensor)
31 Vapor passage (first vapor passage)
33 Pressure sensor (first pressure sensor)
35 Sealing valve 38 Control part (Mutual monitoring part, Immersion detection part, Monitoring prohibition part)
50 canister

Claims (3)

A fuel tank for storing fuel;
A first pressure sensor and a second pressure sensor for detecting pressure in the fuel tank from different positions in the fuel tank;
A mutual monitoring unit for mutually monitoring detected pressures output from the first pressure sensor and the second pressure sensor;
A canister that adsorbs fuel evaporative gas generated in the fuel tank;
A leveling valve which is provided in the fuel tank and regulates that the fuel is supplied to the fuel tank;
A first vapor passage that communicates the leveling valve and the canister and guides the evaporated gas in the fuel tank to the canister;
A sealing valve that normally closes the first vapor passage and seals the inside of the fuel tank;
An immersion detection unit for detecting immersion of the leveling valve into the fuel liquid level when the sealing valve is opened;
And a monitoring prohibiting unit that prohibits mutual monitoring of the mutual monitoring unit when the leveling valve is detected to be immersed. The fuel tank communicates a fuel cut-off valve that regulates the liquid level of the fuel tank at a liquid level higher than the leveling valve, the fuel cut-off valve, and the leveling valve, and evaporates the fuel tank. A second vapor passage for guiding gas through the leveling valve to the canister;
One of the first pressure sensor and the second pressure sensor is provided in a first vapor passage portion between the leveling valve and the sealing valve, and the other is provided in the fuel tank,
The immersion sensor is configured to determine whether the leveling valve is immersed in a fuel level based on fluctuations in pressure detected by the first pressure sensor and the second pressure sensor. 2. The fuel device for a vehicle according to 1. The mutual monitoring unit compares the detection result of the first pressure sensor with the detection result of the second pressure sensor, and the first pressure sensor or the second pressure sensor is abnormal based on the comparison result. The vehicle fuel device according to claim 1, wherein the vehicle fuel device is configured to include a determination unit for determining.

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