JP2015121113A - Fuel evaporative emission control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inhibit a fuel tank from getting into a high pressure state.SOLUTION: A fuel evaporative emission control system 1 includes a canister 31 for adsorbing fuel evaporative emission in a purge pipe 39 and a vapor pipe 38 communicated with an intake passage 11 of an engine 10 and with a fuel tank 21, respectively, a purge valve 37 for opening/closing the purge pipe 39, a sealing valve 33 for opening/closing the vapor pipe 38, a pressure sensor 25 for detecting a pressure in the fuel tank 21, and a relief valve 34 provided in the vapor pipe 38 in parallel to the sealing valve 33. When the pressure in the fuel tank 21, detected by the pressure sensor 25 during stopping the engine 10, is the relief pressure of the relief valve 34 or higher, an ECU 50 opens the sealing valve 33 and also opens the purge valve 37 when starting the engine 10.

Description

  The present invention relates to a fuel evaporative emission control device, and more particularly to purge control in a sealed fuel tank.

  Conventionally, in order to prevent the fuel evaporative gas evaporated in the fuel tank of the vehicle from being released to the atmosphere, a canister that is interposed in a communication passage that connects the fuel tank and the intake passage of the internal combustion engine, a fuel tank and a canister A fuel evaporative gas emission suppression device has been developed that includes a sealing valve that communicates or blocks the air and a purge valve that communicates and blocks the communication path between the intake passage and the canister. When refueling, the fuel evaporative emission control device opens the sealing valve and closes the purge valve before opening the refueling port so that the fuel evaporative gas in the fuel tank flows out into the canister, and the fuel evaporative gas is disposed in the canister. By adsorbing to the activated carbon provided, the release of fuel evaporative gas during refueling is prevented. The fuel evaporative emission control device opens the purge valve during operation of the internal combustion engine and discharges the fuel evaporative gas adsorbed on the activated carbon of the canister into the intake passage of the internal combustion engine to process the fuel evaporative gas (canister purge).

Further, in the fuel tank sealed by the sealing valve in this way, when the pressure in the fuel tank becomes high, the purge valve and the sealing valve are opened when the internal combustion engine is operated, and the fuel evaporative gas in the fuel tank is sucked into the intake tank. The fuel evaporative gas in the fuel tank and the communication passage is processed by discharging into the passage (tank purge).
In addition, a relief valve is provided in the communication passage in parallel with the sealing valve. When the pressure in the fuel tank exceeds a predetermined pressure, the relief valve is opened to release fuel evaporative gas from the fuel tank to the communication passage. Even when the valve cannot be opened, the fuel tank does not become high pressure (Patent Document 1).

Japanese Patent No. 4082263

  However, even if the tank purge is possible as in the above-mentioned Patent Document 1, in a vehicle with a long stop time of the internal combustion engine such as a plug-in hybrid vehicle, the opportunity for the tank purge is reduced, and the pressure in the fuel tank is reduced. May be maintained at a high pressure. Even if the relief valve is opened and the fuel evaporative gas in the fuel tank is released into the communication path, the fuel evaporative gas in the communication path cannot be processed while the internal combustion engine is stopped, and the pressure in the fuel tank Cannot be reduced sufficiently.

  The present invention has been made to solve such problems, and an object of the present invention is to provide a fuel evaporative emission control device that suppresses the fuel tank from becoming a high pressure state.

  In order to achieve the above object, in the fuel evaporative emission control device according to claim 1, a communication passage communicating the intake passage of the internal combustion engine and a fuel tank, a canister for adsorbing the fuel evaporative gas in the communication passage, A purge valve that opens and closes communication between the communication passage and the intake passage, a sealing valve that opens and closes the fuel tank so as to open or close the communication passage, and a tank pressure detection unit that detects an internal pressure of the fuel tank; A relief valve provided in the communication path in parallel with the sealing valve, and an internal pressure of the fuel tank detected by the tank pressure detection unit when the internal combustion engine is stopped is equal to or higher than a relief pressure of the relief valve. And a first emergency purge control unit for opening the sealing valve and starting the internal combustion engine to open the purge valve.

According to a second aspect of the present invention, there is provided the fuel evaporative emission control device according to the first aspect, wherein the fuel evaporative emission control device includes a closing valve that closes the canister and the communication passage by closing the passage. The first emergency purge control unit closes the shut-off valve when the internal combustion engine is started.
According to a third aspect of the present invention, there is provided the fuel evaporative emission control device according to the first aspect, wherein the fuel evaporative gas emission control device closes the canister and the communication passage by closing the passage, and the internal combustion engine. And a second emergency purge control unit that opens the closing valve when the engine is started.

  According to a fourth aspect of the present invention, there is provided the fuel evaporative emission control device according to any one of the first to third aspects, wherein the fuel evaporative emission control device controls a valve opening rate of the purge valve and the internal combustion engine. A third emergency purge control unit for reducing the opening rate of the purge valve when the internal pressure of the fuel tank detected by the tank pressure detection unit when starting the engine is equal to or higher than the relief pressure of the relief valve; , Provided.

  According to a fifth aspect of the present invention, there is provided the fuel evaporative gas emission suppression device according to the fourth aspect, wherein the fuel evaporative gas emission suppression device opens the purge valve after closing the sealing valve while the internal combustion engine is operated. A third cantilever purge control unit, wherein a canister purge control unit purges the inside of the canister purge by discharging the fuel evaporative gas adsorbed by the canister into the intake passage and supplying the fuel evaporative gas to the internal combustion engine. The unit is characterized in that when the purge in the canister is being performed, the valve opening rate of the purge valve is decreased.

  According to the first aspect of the invention, the first emergency purge control unit opens the sealing valve when the internal pressure of the fuel tank is equal to or higher than the relief pressure of the relief valve when the internal combustion engine is stopped. Since the internal combustion engine is started and the purge valve is opened, the fuel evaporative gas in the fuel tank can be discharged into the intake passage and supplied to the internal combustion engine for processing. Therefore, even in a vehicle such as a plug-in hybrid vehicle where the stop time of the internal combustion engine is long, the fuel tank can be prevented from being in a high pressure state.

According to the second aspect of the present invention, the canister and the communication path are closed by closing the closing valve when the internal combustion engine is started by the first emergency purge control unit, and the fuel that has flowed into the communication path from the fuel tank. It is possible to prevent the evaporated gas from adsorbing to the canister. Thereby, the adsorbable amount of the fuel evaporative gas in the canister can be secured.
According to the invention of claim 3, since the closing valve is opened when the internal combustion engine is started when the internal pressure of the fuel tank is equal to or higher than the relief pressure of the relief valve, the fuel evaporative gas in the fuel tank is introduced into the intake passage. In addition to being released, it can be adsorbed by the canister, and the pressure in the fuel tank can be rapidly reduced.

According to the invention of claim 4, when the internal pressure of the fuel tank is equal to or higher than the relief pressure of the relief valve when the internal combustion engine is started, the valve opening rate of the purge valve is reduced. It is possible to prevent the stop of the internal combustion engine by suppressing the amount of gas inflow and suppressing the operation of the internal combustion engine from becoming unstable.
According to the invention of claim 5, when the canister purge for releasing the fuel evaporative gas adsorbed by the canister to the intake passage is performed, the valve opening rate of the purge valve is reduced. Even if high-concentration fuel evaporative gas in the tank flows into the communication path, it is possible to prevent the operation of the internal combustion engine from becoming unstable and prevent the internal combustion engine from stopping.

1 is a schematic configuration diagram of a fuel evaporative emission control device according to the present invention. It is explanatory drawing which shows the operating state of each valve | bulb at the time of canister purge. It is explanatory drawing which shows the operating state of each valve | bulb at the time of completion | finish of canister purge. It is explanatory drawing which shows the operating state of each valve | bulb at the time of tank purge. It is a flowchart which shows the purge control point at the time of relief valve opening.

Hereinafter, a fuel evaporative emission control device according to the present invention will be described with reference to the drawings.
FIG. 1 is a schematic configuration diagram of a fuel storage device for a vehicle provided with a fuel evaporative emission control device according to the present invention.
The fuel evaporative emission control device according to the present invention is employed in a hybrid vehicle or a plug-in hybrid vehicle that can automatically start the engine 10 (internal combustion engine).

  As shown in FIG. 1, the fuel storage device according to this embodiment includes an engine 10 that is largely mounted on a vehicle, a fuel storage unit 20 that stores fuel, and a fuel evaporation that is an evaporated gas of fuel evaporated in the fuel storage unit 20. A fuel evaporative gas processing unit 30 for processing gas, and an electronic control unit (hereinafter referred to as ECU) 50 (canister purge control unit, control unit, first emergency purge) which is a control device for performing comprehensive control of the vehicle A control unit, a second emergency purge control unit, a third emergency purge control unit), a momentary operation type oil supply lid switch 61 for operating an opening operation of an oil supply lid 23, which will be described later, and a display 63 for displaying a vehicle state and the like. A momentary operation type main switch 64 for connecting / disconnecting the main power supply of the vehicle is provided.

  The engine 10 is an intake passage injection (MPI) gasoline engine. The engine 10 is provided with an intake passage 11 that takes air into the combustion chamber of the engine 10. The intake passage 11 is provided with an intake pressure sensor 14 that detects the internal pressure of the intake passage 11. A fuel injection valve 12 that injects fuel into the intake port of the engine 10 is provided downstream of the intake passage 11. A fuel pipe 13 is connected to the fuel injection valve 12 and fuel is supplied.

  The fuel storage unit 20 includes a fuel tank 21 that stores fuel, a fuel supply port 22 that is a fuel injection port to the fuel tank 21, a fuel supply lid 23 that is a lid of the fuel supply port 22 provided in the vehicle body of the vehicle, A lid lock mechanism 65 that locks the fuel supply lid 23 in a closed state, a fuel pump 24 that supplies fuel from the fuel tank 21 to the fuel injection valve 12 via the fuel pipe 13, and a pressure (internal pressure) in the fuel tank 21 is detected. And a fuel cut-off valve 26 that has a float valve (not shown) inside and prevents the outflow of fuel from the fuel tank 21 to the fuel evaporative gas processing unit 30 by the action of the float valve. And an inner diameter smaller than the inner diameter of a leveling valve 27 for controlling the liquid level in the fuel tank 21 during refueling, and a pipe such as a vapor pipe 38 and a purge pipe 39 described later. A two-way valve 28 that has an orifice (for example, φ1.0 mm) and limits the amount of fuel supplied when the fuel tank 21 is full of fuel, that is, additional fuel, and fuel in the fuel tank 21 (not shown) It is comprised with the fuel quantity detection apparatus which detects quantity. Further, the fuel evaporative gas generated in the fuel tank 21 passes from the lower part of the leveling valve 27 to the outside of the fuel tank 21 or from the fuel cut-off valve 26 via the two-way valve 28 and the leveling valve 27. Discharged outside.

The fuel evaporative gas processing unit 30 includes a canister 31, a bypass valve 32 (closing valve), a sealing valve 33, a relief valve 34, an air filter 35, a purge valve 37, a vapor pipe 38 (communication path), a purge It is comprised with the piping 39 (communication path).
The canister 31 has activated carbon inside. Further, the canister 31 is provided with an evaporative gas flow hole 31a through which the fuel evaporative gas generated in the fuel tank 21 or the fuel evaporative gas adsorbed on the activated carbon flows. Further, the canister 31 is provided with an outside air intake hole 31b through which outside air is sucked when the fuel evaporative gas adsorbed on the activated carbon is released. Further, the outside air suction hole 31b is connected so as to communicate one side that prevents entry of dust from the outside with the other side of the air filter 35 that is open to the atmosphere.

  The bypass valve 32 is provided with a canister connection port 32 a connected so as to communicate with the evaporative gas flow hole 31 a of the canister 31. The bypass valve 32 has a vapor pipe connection port 32b connected to the other end of the vapor pipe 38, one end of which is connected to the leveling valve 27 of the fuel tank 21, and one end of the engine 10 to the engine 10. A purge pipe connection port 32c connected to communicate with the other end of the purge pipe 39 connected to communicate with the intake passage 11 is provided. The vapor piping connection port 32b and the purge piping connection port 32c of the bypass valve 32 are connected to a vapor piping 38 and a purge piping 39, respectively. The bypass valve 32 is a normally open type electromagnetic valve that opens in a non-energized state and is in a closed state when a drive signal is supplied from the outside and energized. When the bypass valve 32 is not energized and is open, the canister connection port 32a, the vapor piping connection port 32b, and the purge piping connection port 32c communicate with each other so that the fuel evaporative gas is supplied to the canister 31. This allows inflow and outflow and inflow of air sucked from the air filter 35 into the vapor pipe 38 and the purge pipe 39. Further, when the bypass valve 32 is supplied with a drive signal from the outside and is energized and closed, the canister connection port 32a is blocked, and only the vapor piping connection port 32b and the purge piping connection port 32c are communicated to each other. The flow of fuel evaporative gas into and out of the air 31 and the inflow of air from the air filter 35 to the vapor pipe 38 and the purge pipe 39 are disabled. That is, the bypass valve 32 closes the canister 31 when the valve is closed, and opens the canister 31 when the valve is open.

  The sealing valve 33 is interposed in the vapor pipe 38. The sealing valve 33 is a normally closed electromagnetic valve that closes in a non-energized state and opens when a drive signal is supplied from the outside to be energized. The sealing valve 33 closes the vapor pipe 38 when it is in a non-energized state and is closed, and opens the vapor pipe 38 when a drive signal is supplied from the outside and the valve is open when energized. That is, if the sealing valve 33 is in the closed state, the fuel tank 21 is sealed and the fuel evaporative gas generated in the fuel tank 21 cannot flow out of the fuel tank 21, and the sealing valve 33 is in the opened state. For example, the fuel evaporative gas can flow out to the canister 31.

The relief valve 34 is interposed in the vapor pipe 38 in parallel with the sealing valve 33. The relief valve 34 is mechanically opened when the internal pressure of the fuel tank 21 rises, and releases the pressure to the canister 31 to prevent the fuel tank 21 from bursting.
The purge valve 37 is interposed in a purge pipe 39 between the intake passage 11 of the engine 10 and the bypass valve 32. The purge valve 37 is a normally closed electromagnetic valve that closes in a non-energized state and opens when a drive signal is supplied from the outside to be energized. The purge valve 37 closes the purge pipe 39 when it is not energized and closed, and opens the purge pipe 39 when a drive signal is supplied from the outside and the valve is open when energized. That is, if the purge valve 37 is in the closed state, the fuel evaporative gas cannot be flowed out from the fuel evaporative gas processing unit 30 to the engine 10, and if it is in the open state, the fuel evaporative gas can be flowed out to the engine 10. .

The display 63 displays the vehicle state. For example, the time from the operation of the fueling lid switch 61 until the fueling lid 23 is unlocked, the stop operation of the fueling lid 23, the open / closed state of the fueling lid 23, etc. Is displayed.
The ECU 50 includes an input / output device, a storage device (ROM, RAM, nonvolatile RAM, etc.), a central processing unit (CPU), a timer, and the like.

The intake pressure sensor 14, the pressure sensor 25, the oil supply lid switch 61, and the main switch 64 are connected to the input side of the ECU 50, and detection information from these sensors is input.
On the other hand, the fuel injection valve 12, the fuel pump 24, the bypass valve 32, the sealing valve 33, the purge valve 37, the display 63, and the door motor 86 provided in the lid lock mechanism 65 are connected to the output side of the ECU 50.

  The ECU 50 controls the opening and closing of the oil supply lid 23 by controlling the operation of the door motor 86 of the lid lock mechanism 65 based on detection information from various sensors, and also controls the opening and closing of the bypass valve 32, the sealing valve 33, and the purge valve 37. The pressure of the vapor pipe 38 and the purge pipe 39 between the fuel tank 21 and the sealing valve 33 and the purge valve 37, the adsorption of the fuel evaporative gas to the canister 31, and the fuel evaporative gas adsorbed to the canister 31 The fuel evaporative gas flow such as outflow to the intake passage 11 of the engine 10 is controlled.

Further, the ECU 50 can control the valve opening rate of the purge valve 37 (control unit). Control of the valve opening rate of the purge valve 37 may be performed by duty control of the opening / closing time of the purge valve 37, or may be performed by changing the opening degree of the purge valve 37.
2 to 4 are explanatory views showing the operating states of the sealing valve 33, the bypass valve 32, and the purge valve 37. FIG. 2 shows a canister purge, FIG. 3 shows a canister purge end, and FIG. 4 shows a tank purge. 2 to 4, the solid arrow indicates the fuel evaporative gas moving path, and the broken arrow indicates the atmospheric moving path.

The ECU 50 performs a canister purge in which the fuel evaporative gas adsorbed by the canister 31 is discharged to the intake passage 11 for processing during engine operation. The canister purge is performed for a predetermined time immediately after the engine 10 is started, for example.
The ECU 50 opens the purge valve 37 and the bypass valve 32 as shown in FIG. 2 during engine operation as canister purge. At this time, the sealing valve 33 is closed (canister purge control unit).

As a result, the purge pipe 39 and the canister 31 communicate with the intake passage 11 of the engine 10, so that the atmosphere from the outside air intake port of the canister to the intake passage 11 that has become negative pressure due to the operation of the engine 10, the purge pipe 39 Inflow through. Therefore, the fuel evaporative gas adsorbed by the canister 31 is discharged to the intake passage 11 and processed.
When the canister purge is completed or the engine 10 is stopped, the purge valve 37 is closed as shown in FIG. This prevents the fuel evaporative gas from being discharged into the intake passage 11. When the engine 10 is stopped, the inside of the intake passage 11 is at atmospheric pressure, so that canister purge becomes impossible. Therefore, the communication between the canister 31 and the intake passage 11 is blocked by closing the purge valve 37.

The ECU 50 performs tank purge when the pressure in the fuel tank 21 detected by the pressure sensor 25 is equal to or higher than the predetermined pressure P1 during operation of the engine 10.
In the tank purge, the ECU 50 opens the sealing valve 33 and the purge valve 37 and closes the bypass valve 32 as shown in FIG.
As a result, the fuel tank 21 communicates with the intake passage 11 of the engine 10 via the purge pipe 39 and the vapor pipe 38, so that the fuel tank 21 passes the purge pipe 39 to the intake passage 11 that has become a negative pressure due to the operation of the engine 10. The fuel evaporative gas flows through the vapor pipe 38. Therefore, the fuel evaporative gas in the fuel tank 21 is discharged into the intake passage 11 and processed.

The tank purge is performed until the pressure P in the fuel tank 21 detected by the pressure sensor 25 becomes equal to or lower than a predetermined pressure P1.
The ECU 50 starts canister purge when the engine is started, for example. If the pressure P in the fuel tank 21 detected by the pressure sensor 25 is higher than a predetermined pressure P1, the ECU 50 performs the above-described tank purge and performs pressure in the fuel tank 21. P is lowered below a predetermined pressure P1. However, for example, when the sealing valve 33 is closed and fixed, the tank purge is not sufficiently performed, and the pressure P in the fuel tank 21 may increase. Thus, when the pressure P in the fuel tank 21 rises and becomes higher than the relief pressure P2 of the relief valve 34, the relief valve 34 is mechanically opened.

  In some cases, the tank purge is set not only to the pressure in the fuel tank 21 but also to a canister purge when it is performed for a certain period (a certain time or a certain amount of operation of the engine 10). When the sealing valve 33 is closed and fixed, the canister purge may be executed in a state where the pressure in the fuel tank 21 is higher than the relief pressure P2 of the relief valve 34. In addition, during the canister purge, the pressure P in the fuel tank 21 may increase rapidly and become higher than the relief pressure P2 of the relief valve 34.

In the present embodiment, the ECU 50 is characterized by purge control in a state where the relief valve 34 is opened as described above.
FIG. 5 is a flowchart showing a purge control procedure when the relief valve is open.
The purge control procedure when the relief valve is opened as shown in FIG. 5 is repeatedly performed every predetermined time when the main switch 64 is ON.

First, in step S10, the pressure P in the fuel tank 21 detected by the pressure sensor 25 is input. Then, the process proceeds to step S20.
In step S20, it is determined whether or not the pressure P in the fuel tank 21 input in step S10 is equal to or higher than the relief pressure P2 of the relief valve 34. The relief pressure P2 is set to a value higher than the predetermined pressure P1, which is the threshold value for determining the start of tank purge. When the pressure P in the fuel tank 21 is equal to or higher than the relief pressure P2, the process proceeds to step S30. When the pressure P in the fuel tank 21 is less than the relief pressure P2, this routine ends.

In step S30, it is determined whether or not the above-described canister purge is being performed. If the canister purge is in progress, the process proceeds to step S40. If the canister purge is not in progress, the process proceeds to step S50.
In step S40, purge rate reduction control is performed to reduce the purge rate in the canister purge from the normal purge rate. The purge rate reduction control is performed by reducing the valve opening rate of the purge valve 37 as described above. Then, this routine ends.

In step S50, it is determined whether or not the engine 10 is stopped. If it is stopped, the process proceeds to step S60. If the engine is operating, the process proceeds to step S70.
In step S60, the engine 10 is started. Then, the process proceeds to step S70.
In step S70, emergency purge control is performed. In the emergency purge control, the purge valve 37 and the sealing valve 33 are opened and the bypass valve 32 is closed as in tank purge. Then, this routine ends.

The control in steps S10 to S40 corresponds to the third emergency purge control unit of the present invention, and the emergency purge control in steps S10, 20, and 50 to S70 is the first emergency purge control unit of the present invention. It corresponds to.
As described above, in the present embodiment, the ECU 50 determines that the main switch 64 is ON and the engine 10 is stopped when the pressure P in the fuel tank 21 is equal to or higher than the relief pressure P2 of the relief valve 34. Starts the engine 10 and opens the purge valve 37 and the sealing valve 33 like a tank purge.

  Thus, when the pressure P in the fuel tank 21 is higher than the relief pressure P2 of the relief valve 34, even if the engine 10 is stopped, the engine 10 is forcibly operated to purge the purge valve 37 and the sealing valve. 33 is opened, and the fuel evaporative gas in the fuel tank 21 is discharged into the intake passage 11 for processing, so that the pressure in the fuel tank 21 can be ensured even in a vehicle with a long stoppage time of the engine 10 such as a plug-in hybrid vehicle. Can be lowered. At this time, since the bypass valve 32 is closed, it is possible to prevent the fuel evaporative gas from adsorbing to the canister 31 and to secure an adsorbable amount of the fuel evaporative gas in the canister 31. .

Since the predetermined pressure P1 for starting the tank purge is set lower than the relief pressure P2 of the relief valve 34, if the pressure P in the fuel tank 21 is equal to or higher than the predetermined pressure P1 and lower than the relief pressure P2, the engine 10 When the engine is in an operating state, the tank purge is performed, and the pressure in the fuel tank 21 can be reduced.
In addition, when the pressure P in the fuel tank 21 is equal to or higher than the relief pressure P2 of the relief valve 34, the ECU 50 opens the relief valve 34 and passes the relief valve 34 from the fuel tank 21 so that the fuel evaporative gas is generated. If it is determined that the gas is discharged to the vapor pipe 38 and canister purge is in progress, control is performed to lower the valve opening rate of the purge valve 37 than the purge rate during normal canister purge.

Thus, during canister purge, the pressure P in the fuel tank 21 is equal to or higher than the relief pressure P2 of the relief valve 34, and the fuel evaporative gas is discharged from the fuel tank 21 through the relief valve 34 to the vapor pipe 38. Then, the fuel evaporative gas from the fuel tank 21 together with the fuel evaporative gas from the canister 31 is discharged to the intake passage 11 through the purge pipe 39.
When the pressure in the fuel tank 21 is high, the concentration of the fuel evaporative gas in the fuel tank 21 is higher than the concentration of the fuel evaporative gas discharged from the canister 31. If the fuel evaporative gas passes from the tank 21 through the relief valve 34 and flows out to the vapor pipe 38, the high-concentration fuel evaporative gas is discharged to the intake passage 11, and the operation of the engine 10 may become unstable and stop. is there.

Therefore, the ECU 50 can reduce the flow rate of the fuel evaporative gas discharged to the intake passage 11 by reducing the purge rate of the purge valve 37 as described above, and can prevent the engine from being stopped.
Further, in the emergency purge control in step S70, the bypass valve 32 may be opened. Thus, by opening the bypass valve 32, the combustion evaporative gas in the fuel tank 21 can be not only discharged into the intake passage 11 for processing but also adsorbed by the canister 31. Thereby, the pressure in the fuel tank 21 can be rapidly reduced. The emergency purge control by the ECU 50 at this time corresponds to the second emergency purge control unit of the present invention.

This is the end of the description of the embodiment of the invention. However, the embodiment of the present invention is not limited to this embodiment.
For example, only the emergency purge control may be performed among the emergency purge control and the canister purge purge rate reduction control of the above embodiment.
Further, the present invention can be widely applied to vehicles capable of automatically starting an engine, such as a hybrid vehicle and a plug-in hybrid vehicle, and having a sealing valve and a relief valve and capable of tank purging.

21 Fuel tank 25 Pressure sensor (tank pressure detector)
31 Canister 32 Bypass valve (closing valve)
33 Sealing valve 34 Relief valve 37 Purge valve 38 Vapor piping (communication path)
39 Purge piping (communication passage)
50 ECU (canister purge control unit, control unit, first emergency purge control unit, second emergency purge control unit, third emergency purge control unit)

Claims (5)

A communication passage communicating the intake passage of the internal combustion engine and the fuel tank;
A canister that adsorbs fuel evaporative gas in the communication path;
A purge valve that opens and closes communication between the communication passage and the intake passage;
A sealing valve that opens and closes the fuel tank so as to open or block the communication passage;
A tank pressure detector for detecting the internal pressure of the fuel tank;
A relief valve provided in the communication path in parallel with the sealing valve;
When the internal pressure of the fuel tank detected by the tank pressure detection unit when the internal combustion engine is stopped is equal to or higher than the relief pressure of the relief valve, the sealing valve is opened and the internal combustion engine is started and the internal combustion engine is started. A first emergency purge control that opens the purge valve;
A fuel evaporative emission control device. The fuel evaporative emission control device is
A closing valve for closing the canister and the communication passage by closing the passage;
2. The fuel evaporative emission control device according to claim 1, wherein the first emergency purge control unit closes the closing valve when the internal combustion engine is started. The fuel evaporative emission control device is
A closing valve for closing the canister and the communication passage by closing the passage;
A second emergency purge control unit for opening the closing valve when starting the internal combustion engine;
The fuel evaporative emission control device according to claim 1. The fuel evaporative emission control device
A control unit for controlling a valve opening rate of the purge valve;
When the internal pressure of the fuel tank detected by the tank pressure detection unit when starting the internal combustion engine is equal to or higher than the relief pressure of the relief valve, a third emergency purge that reduces the valve opening rate of the purge valve A control unit;
The fuel evaporative emission control device according to any one of claims 1 to 3, further comprising: The fuel evaporative emission control device is
The purge valve is opened after the sealing valve is closed while the internal combustion engine is operated, and the fuel evaporative gas adsorbed by the canister is discharged into the intake passage and supplied to the internal combustion engine. A canister purge control unit for purging the inside of the canister,
5. The fuel evaporative emission control device according to claim 4, wherein the third emergency purge control unit decreases the valve opening rate of the purge valve when the canister is purged. 6.

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