JP2012180824A - Evaporated fuel treatment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an evaporated fuel treatment device which treats the evaporated fuel generated in a fuel tank by purging a canister and releasing the pressure of the tank without using the negative pressure of an engine.SOLUTION: The evaporated fuel treatment device includes: a pressure sensor 17 which measures the inner pressure of the fuel tank 10; and an opening/closing valve 44 provided on a passage communicating the fuel tank 10 with an intake pipe 46 of the internal combustion engine. When the inner pressure of the fuel tank 10 is not less than a predetermined value, the opening/closing valve 44 is opened to communicate the fuel tank 10 with the intake pipe 46.

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an evaporative fuel processing apparatus that processes evaporative fuel generated in a fuel tank of a vehicle and appropriately processes evaporative fuel without using a negative pressure of an internal combustion engine.

  2. Description of the Related Art Conventionally, a vehicle using gasoline or the like is equipped with an evaporative fuel processing device that prevents the evaporative fuel from being diffused into the atmosphere while avoiding damage due to an increase in the internal pressure of the fuel tank. A typical evaporative fuel processing apparatus has a canister that adsorbs evaporative fuel generated in a fuel tank, and purges the canister using a negative pressure generated during operation of the internal combustion engine, thereby desorbing the canister. The fuel vapor is configured to burn in the internal combustion engine.

  However, in the case of a hybrid vehicle using both an internal combustion engine and a motor, no negative pressure is generated in the internal combustion engine because the internal combustion engine is stopped while the motor is running. Therefore, the canister cannot be purged during traveling by the motor, and it is difficult to appropriately process the evaporated fuel. In order to solve this problem, for example, there is an evaporative fuel processing apparatus that can appropriately process evaporative fuel even when the internal combustion engine is stopped, as described in Patent Document 1 below. In the evaporative fuel processing apparatus of Patent Document 1, the evaporative fuel generated in the fuel tank is supplied to the canister, and when the internal combustion engine is operating, the canister is purged using the negative pressure generated in the internal combustion engine as usual. The evaporated fuel desorbed thereby is burned in the internal combustion engine. On the other hand, when the internal combustion engine is stopped and the motor is operating, the evaporative fuel processing device moves the internal combustion engine with the power of the motor and flows air to the catalyst installed on the exhaust passage of the internal combustion engine. This makes it possible to supply the evaporated fuel adsorbed by the canister to the catalyst and burn it.

JP 2009-24612 A

  However, in the evaporative fuel processing apparatus of Patent Document 1, when the internal combustion engine is operating, the canister is purged using the negative pressure generated in the internal combustion engine as usual. Therefore, if the pumping loss of the internal combustion engine is reduced in the future and the negative pressure generated in the internal combustion engine is reduced or almost eliminated, the canister may not be sufficiently purged. If the canister is not sufficiently purged, there is a possibility that even if newly evaporated fuel flows into the canister, all of the fuel cannot be adsorbed.

  Further, the evaporative fuel processing apparatus of Patent Document 1 supplies all the evaporative fuel generated in the fuel tank to the canister, and burns the evaporative fuel that has not been desorbed from the canister by the purge with the catalyst. Therefore, when the amount of evaporated fuel recovered by the internal combustion engine by purging the canister decreases, the amount of evaporated fuel burned by the catalyst, that is, the amount of fuel that is not used for the operation of the internal combustion engine increases. Fuel economy will worsen.

  The present invention has been made in view of such circumstances. The problem to be solved by the present invention is to purge the canister appropriately without using the negative pressure generated by the internal combustion engine and to increase the proportion of evaporated fuel combusted in the internal combustion engine.

In order to solve the above problems, the evaporative fuel processing apparatus according to the present invention employs the following means.
An evaporative fuel processing apparatus according to a first aspect of the present invention includes a fuel tank for storing fuel supplied to an internal combustion engine and a canister capable of adsorbing evaporative fuel in the fuel tank, and at least when fueling the fuel tank An evaporative fuel treatment device that supplies evaporative fuel generated in the fuel tank to the canister, and can pump the evaporative fuel desorbed from the canister by a pump that desorbs the evaporative fuel from the canister by introducing air into the canister And a pressure sensor that can measure the internal pressure of the fuel tank, and a passage that connects the fuel tank and the intake pipe of the internal combustion engine, and the passage is communicated and blocked by an on-off valve installed in the passage. A tank fuel purge passage, and the internal pressure of the fuel tank during operation of the internal combustion engine is detected by a pressure sensor so that the internal pressure of the fuel tank exceeds a predetermined value. And an open state of the closing valve in some cases, when the fuel tank internal pressure is less than the predetermined value, characterized in that is configured to perform control of the on-off valve in a closed state.

  According to this evaporative fuel processing apparatus, the evaporative fuel adsorbed by the canister during refueling is desorbed and burned by the catalyst when the pump introduces the atmosphere into the canister. Therefore, even in a vehicle equipped with an internal combustion engine that generates little or no negative pressure due to operation, the evaporated fuel can be reliably desorbed from the canister, so that the evaporated fuel does not adsorb to the canister. Can be prevented from being released into Further, when the internal pressure of the fuel tank is greater than or equal to a predetermined value during operation of the internal combustion engine, the on-off valve is opened and the fuel tank and the intake pipe of the internal combustion engine communicate with each other. At this time, since the tank internal pressure is a positive pressure, the evaporated fuel flows from the fuel tank into the intake pipe of the internal combustion engine, and the tank can be prevented from being damaged. Further, since the evaporated fuel generated in the fuel tank other than at the time of refueling is supplied to the internal combustion engine and combusted, fuel efficiency can be improved as compared with the case where all the evaporated fuel is supplied to the canister.

  An evaporative fuel processing apparatus according to a second invention is the evaporative fuel processing apparatus according to the first invention, comprising a tank passage valve for communicating / blocking a tank passage for communicating a fuel tank and a canister, and a tank passage valve The valve is controlled to be opened when refueling and closed when not refueling.

  According to this fuel vapor processing apparatus, the fuel tank and the canister can communicate with each other only during refueling by controlling the tank passage valve. Accordingly, the communication between the fuel tank and the canister can be appropriately switched between communication and cutoff, and the fuel tank can be easily kept in a sealed state except during refueling.

  An evaporative fuel processing apparatus according to a third invention is the evaporative fuel processing apparatus according to the first or second invention, wherein a shunt capable of bypassing the atmosphere introduced by the pump before the catalyst without passing through the canister. The shunt is characterized by being capable of diverting the atmosphere to an arbitrary flow rate and adjusting the concentration of the evaporated fuel supplied to the catalyst.

  According to this fuel vapor processing apparatus, the amount of fuel vapor desorbed from the canister can be adjusted by adjusting the amount of air introduced into the canister, so the concentration of fuel vapor supplied to the catalyst is adjusted. can do. As a result, it is possible to supply the evaporated fuel to the catalyst at an optimum concentration for combustion. As a result, it is possible to reduce the concentration of exhaust gas discharged after combustion and avoid air pollution.

  An evaporative fuel processing apparatus according to a fourth aspect of the present invention is the evaporative fuel processing apparatus according to any of the first to third aspects of the present invention, comprising a catalyst passage valve that communicates and blocks a catalyst passage that communicates the canister and the catalyst. A heater for heating the catalyst, and when evaporating fuel is burned by the catalyst, the catalyst is heated to the activation temperature by the heater, and then the catalyst passage valve is opened and the pump is driven. It is characterized by.

  According to this evaporative fuel processing apparatus, after the catalyst is heated to the activation temperature, the catalyst passage valve is opened and the pump is driven, so that the evaporative fuel is supplied to the catalyst before the catalyst reaches the activation temperature. It can prevent being supplied. Thereby, since evaporative fuel can be prevented from being released into the atmosphere without being burned, air pollution can be avoided.

  An evaporated fuel processing apparatus according to a fifth aspect of the present invention is the evaporated fuel processing apparatus according to any of the first to fourth aspects of the present invention, wherein the internal pressure of the fuel tank is not less than a predetermined value and A When the / F feedback control is possible, the fuel vapor generated in the fuel tank is supplied to the intake pipe.

  According to this fuel vapor processing apparatus, since the A / F feedback control is possible when the fuel vapor is supplied to the intake pipe, the amount of fuel supplied to the engine is determined based on the amount of fuel vapor supplied to the air intake pipe. The supply amount can be feedback controlled. As a result, it is possible to prevent a reduction in fuel consumption and a deterioration in exhaust gas concentration due to fluctuations in the A / F ratio in the engine.

  According to the present invention, it is possible to purge the canister and supply the evaporated fuel generated in the fuel tank to the internal combustion engine without using the negative pressure generated in the internal combustion engine. Therefore, even in a vehicle equipped with an internal combustion engine that generates a small negative pressure, the evaporated fuel can be appropriately processed.

It is a schematic diagram of the evaporative fuel processing apparatus of Example 1. It is a graph which shows the change of the operation temperature of the valve in Example 1, a pump, and a heater, and the catalyst temperature and tank internal pressure accompanying this. It is a schematic diagram of the evaporative fuel processing apparatus of Example 2. It is a graph showing the relationship between the density | concentration of the evaporative fuel supplied to a catalyst, and the density | concentration of exhaust gas. It is a graph showing the relationship between the density | concentration of the fuel vapor supplied to a catalyst, and the temperature of a catalyst.

  Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings. However, the present invention is not limited thereto, and various modifications can be made without departing from the scope of the present invention. In particular, as long as it has a basic configuration including a fuel tank, a canister, a pump, a catalyst, and a pressure sensor, which are essential components for the evaporated fuel processing apparatus of the present invention, various other components can be added. The evaporative fuel processing apparatus can be suitably applied to a vehicle such as an automobile that uses highly volatile fuel (for example, gasoline) as fuel.

Example 1
FIG. 1 is a schematic diagram of an evaporative fuel processing apparatus according to a first embodiment. The evaporative fuel processing apparatus includes a fuel tank 10 that stores fuel F, a canister 12 that adsorbs evaporative fuel generated in the fuel tank 10, an electric pump 14 that introduces air (air) into the canister 12, and evaporative fuel combustion. A catalyst module 16 and a pressure sensor 17 for measuring the internal pressure in the fuel tank 10 are provided.

  The fuel tank 10 is a sealed tank. The fuel tank 10 is provided with a pressure sensor 17 for detecting the internal pressure of the fuel tank 10, a cap 18 for opening and closing the fuel filler port of the fuel tank 10, and a cap sensor 19 for determining the open / closed state of the cap 18. Detection signals from the pressure sensor 17 and the cap sensor 19 are input to an engine control unit (ECU) 20. The fuel tank 10 communicates with the canister 12 through a tank passage 22. A tank passage valve 24 is installed on the tank passage 22, and the tank passage 22 can be switched between a communication state and a cutoff state by opening and closing the tank passage valve 24.

  The canister 12 is filled with an adsorbent C. As the adsorbent C, a porous body that allows air to pass through but adsorbs and desorbs the evaporated fuel can be used. In this embodiment, activated carbon is used. Connected to the canister 12 is an atmospheric passage 26 whose tip is open to the atmosphere. An electric pump 14 and an air filter 28 for introducing air into the canister 12 are installed on the air passage 26. The electric pump 14 is controlled by the ECU 20, and supplies the atmosphere taken in from the tip of the atmosphere passage 26 and passed through the air filter 28 to the canister 12.

  The canister 12 is connected to the catalyst module 16 through the catalyst passage 30. A catalyst passage valve 32 is installed on the catalyst passage 30, and the communication state and the cutoff state of the catalyst passage 30 can be switched by opening and closing the catalyst passage valve 32.

The catalyst module 16 includes a catalyst 34 for burning the evaporated fuel. As the catalyst 34, a catalyst that reacts HC of evaporated fuel with O ₂ in the air to decompose HC into water and carbon dioxide can be used. In this embodiment, a platinum catalyst is used as the catalyst 34. The catalyst module 16 includes a temperature sensor 36 for measuring the temperature of the catalyst 34 and a heater 38 for heating the catalyst 34. The temperature sensor 36 inputs the measured temperature of the catalyst 34 to the ECU 20, and the ECU 20 controls the heater 38 based on the temperature measured by the temperature sensor 36. Since the catalyst 34 is activated at or above the activation temperature inherent to the catalyst, the catalyst 34 is heated by the heater 38 to the activation temperature (activation determination value) before burning the evaporated fuel. Since the combustion reaction of the evaporated fuel by the catalyst 34 is an exothermic reaction, when the combustion of the evaporated fuel is started, the catalyst 34 is kept at a high temperature without being heated by the heater 38. For this reason, the heater 38 may be stopped after the start of combustion. The catalyst module 16 is connected to an exhaust pipe 40 whose tip is open to the atmosphere, and carbon dioxide generated in the catalyst module 16 can be released into the atmosphere.

  The fuel tank 10 communicates with an engine (not shown) through a tank fuel purge passage 42. A tank fuel purge passage valve 44 is installed on the tank fuel purge passage 42. By opening and closing the tank fuel purge passage valve 44, the communication state and the cutoff state of the tank fuel purge passage 42 can be switched. . One end of the tank fuel purge passage 42 is connected to the tank passage 22 between the tank passage valve 24 and the fuel tank 10, and the other end of the tank fuel purge passage 42 is connected to the intake pipe 46. The intake pipe 46 is a pipe that sucks air (air) into the engine during operation of the engine. The intake pipe 46 includes a throttle valve 48 that controls the amount of air taken in according to the amount of depression of an accelerator pedal (not shown), and an air filter 50. The tank fuel purge passage valve 44 corresponds to the on-off valve in this specification.

  The tank fuel purge passage 42 includes an A / F sensor 52 for measuring the amount of evaporated fuel supplied to the engine via the tank fuel purge passage 42. The A / F sensor 52 inputs the measured supply amount of the evaporated fuel to the ECU 20, and the ECU 20 reduces the fuel injected from the injector (not shown) to the engine by the same amount as the supply amount. The feedback control is performed.

  The tank passage valve 24, the catalyst passage valve 32, and the tank fuel purge passage valve 44 are electromagnetic valves whose opening / closing timing is controlled by the ECU 20. The ECU 20 includes a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), and the like. A predetermined control program is stored in advance in the ROM, and the CPU controls each component of the evaporated fuel processing apparatus at a predetermined timing based on the control program.

  Next, the evaporative fuel processing mechanism by the evaporative fuel processing apparatus will be described with reference to FIG. During parking (when the key is off), the tank passage valve 24, the catalyst passage valve 32, and the tank fuel purge passage valve 44 are closed. When the cap 18 is removed from the fuel tank 10 during refueling, a signal from the cap sensor 19 is input to the ECU 20 and the tank passage valve 24 is opened by the ECU 20. When the internal pressure of the fuel tank 10 increases as the fuel is supplied, the evaporated fuel-containing gas in the fuel tank 10 flows into the canister 12 through the tank passage 22. Then, the evaporated fuel is selectively captured by the adsorbent C in the canister 12, and the remaining gas mainly composed of air is discharged to the outside through the atmospheric passage 26. Thereby, the internal pressure of the fuel tank 10 can be reduced while avoiding air pollution, and damage to the fuel tank 10 is prevented. When the cap 18 is attached to the fuel tank 10 after refueling, a signal is input from the cap sensor 19 to the ECU 20, and the ECU 20 closes the tank passage valve 24 based on the signal. Thereby, the fuel tank 10 is sealed again.

When the key-on operation is performed (timing P _{1 in} FIG. 2), the heater 38 heats the catalyst 34 regardless of the operating state of the engine, and the temperature sensor 36 measures the temperature of the catalyst 34. As shown in FIG. 2, when the temperature of the catalyst 34 reaches the activation determination value (timing P ₂ ), the ECU ₂₀ stops the heater 38 and opens the catalyst passage valve 32 to operate the electric pump 14. When the electric pump 14 introduces the air that has passed through the air filter 28 into the canister 12, the evaporated fuel is desorbed from the adsorbent C in the canister 12. The desorbed evaporated fuel flows into the catalyst module 16 through the catalyst passage 30 together with the air introduced into the canister 12. The evaporated fuel-containing gas is combusted by the catalyst 34 in the catalyst module 16 and released from the exhaust pipe 40 into the atmosphere. Thus, the evaporated fuel captured by the canister 12 can be desorbed without using the negative pressure of the engine and burned with the catalyst. When the key-off operation is performed (timing P ₇ ), the ECU 20 stops the electric pump 14 and closes the catalyst passage valve 32.

When the internal pressure of the fuel tank 10 measured by the pressure sensor 17 becomes equal to or higher than a predetermined positive pressure (valve opening determination value) in a state where A / F feedback control is possible while the engine is running (timing P ₃ and P ₅ ), The ECU 20 opens the tank fuel purge passage valve 44. Since the inside of the fuel tank 10 is at a positive pressure, when the tank fuel purge passage valve 44 is opened, the evaporated fuel in the fuel tank 10 flows into the intake pipe 46 through the tank fuel purge passage 42. The evaporated fuel flowing into the intake pipe 46 is supplied to the engine and burned. Here, the A / F sensor 52 measures the amount of evaporated fuel supplied to the engine via the tank fuel purge passage 42, and the measured amount is input to the ECU 20. Since the ECU 20 feedback-controls the amount of fuel injected from the injector into the engine based on the measured amount, the A / F ratio in the engine is kept constant. For this reason, it is possible to prevent an increase in air pollutants in the exhaust resulting from fluctuations in the A / F ratio during combustion, and it is possible to prevent excessive consumption of fuel. When the evaporated fuel in the fuel tank 10 flows into the tank fuel purge passage 42 and the internal pressure of the fuel tank 10 decreases to a predetermined value (for example, atmospheric pressure) (timing P ₄ and P ₆ ), the ECU 20 detects the tank fuel purge passage valve 44. Close. In this way, the internal pressure of the fuel tank 10 is reduced, and damage to the fuel tank 10 is prevented. In addition, the valve opening determination value is less than the pressure resistance strength of the fuel tank 10 and may be a positive pressure, but when the engine is stopped, considering that the tank is not depressurized except during refueling, It is preferable to set a value having a sufficient margin for the pressure strength of the fuel tank 10.

(Example 2)
In the first embodiment, all of the air supplied by the electric pump 14 is introduced into the canister 12, but the evaporative fuel processing apparatus of the second embodiment uses a part of the air supplied from the electric pump 14 without passing through the canister 12. A shunt 60 is provided to supply the catalyst module 16. As shown in FIG. 3, the flow divider 60 is installed on the atmospheric passage 26 between the electric pump 14 and the canister 12. The flow divider 60 is connected to the branch passage 62, and the other end of the branch passage 62 is connected to the catalyst passage 30 between the canister 12 and the catalyst passage valve 32. Therefore, the flow divider 60 can divert the air supplied from the electric pump 14 to the canister 12 and the catalyst passage 30 at an arbitrary ratio. Further, like the other components, the ECU 20 controls the flow divider 60.

When evaporating fuel is burned by the catalyst, as shown in FIG. 4, the concentration of exhaust gas generated after combustion varies depending on the concentration of evaporating fuel supplied to the catalyst, that is, the ratio of air to fuel (A / F ratio). . Specifically, more than increasing concentrations of evaporative fuel supplied to the catalyst, although until reaching the optimum concentration (D ₁₎ the concentration of the exhaust gas produced by combustion lowers, the optimal concentration (D ₁₎ As a result, the concentration of the exhaust gas increases. Therefore, in order to suppress the exhaust gas emission amount, it is necessary to adjust the mixing ratio of the evaporated fuel and the air so that the optimum concentration (D ₁ ) is obtained. Here, the combustion of the evaporated fuel in the catalyst is an exothermic reaction, and the temperature of the burning catalyst varies depending on the concentration of the evaporated fuel supplied to the catalyst, as shown in FIG. That is, when the vaporized fuel having the optimum concentration (D ₁ ) is supplied to the catalyst 34, the temperature of the catalyst 34 is maintained at the optimum temperature (T ₁ ). Therefore, it is possible to supply the evaporative fuel having the optimum concentration (D1) by adjusting the supply amount of the evaporative fuel so that the temperature of the catalyst 34 becomes the optimum temperature (T ₁ ). As a result, the exhaust gas Can be minimized.

In the second embodiment, when a key-on operation is performed, the heater 38 heats the catalyst 34 and the temperature sensor 36 measures the temperature of the catalyst 34. When the temperature of the catalyst 34 rises to the activity determination value, the ECU 20 cuts off the power supply to the heater 38 and stops the heating of the catalyst 34. Then, the ECU 20 operates the electric pump 14 and opens the catalyst passage valve 32. When the electric pump 14 supplies the air (air) that has passed through the air filter 28 to the flow divider 60, the flow divider 60 introduces part of the air into the canister 12, and the remaining air passes through the branch passage 62 and passes through the catalyst passage 30. Introduced into The air introduced into the canister 12 flows into the catalyst passage 30 together with the evaporated fuel desorbed from the adsorbent C, and flows into the catalyst module 16 together with the remaining air supplied to the catalyst passage 30 via the branch passage 62. Supplied and burned. The temperature of the catalyst 34 at this time is measured by the temperature sensor 36 and input to the ECU 20. Here, when the measured catalyst temperature is lower than the optimum temperature (T ₁ ), the ECU 20 controls the flow divider 60 so as to increase the air introduced into the canister 12 and reduce the air flowing through the branch passage 62. As the air introduced into the canister 12 increases, desorption of the evaporated fuel from the adsorbent C is promoted, and as a result, the concentration of the evaporated fuel supplied to the catalyst module 16 increases. On the other hand, when the measured temperature is higher than the optimum temperature (T ₁ ), the ECU 20 controls the flow divider 60 so as to reduce the air introduced into the canister 12 and increase the air flowing through the branch passage 62. By reducing the air introduced into the canister 12, the desorption of the evaporated fuel from the adsorbent C is reduced, and as a result, the concentration of the evaporated fuel supplied to the catalyst module 16 decreases. Thus, by adjusting the amount of air that bypasses the canister 12 based on the catalyst temperature, the concentration of the evaporated fuel supplied to the catalyst module 16 can be adjusted to the optimum concentration (D1). The exhaust gas concentration can be reduced. In addition, since the other structure is the same as Example 1, the same code | symbol is attached | subjected to the same member and the description is abbreviate | omitted.

(Modification)
In the first and second embodiments, the determination of the start and end of refueling is performed based on the signal from the cap sensor 19, but other means may be employed. For example, the start of refueling may be determined by operating a refueling lid open switch, and the end of refueling may be determined by elapse of a predetermined time from the operation, or may be determined by reaching a certain vehicle speed. In the first and second embodiments, since the evaporated fuel in the fuel tank 10 flows into the canister 12 only when refueling, the internal pressure of the fuel tank becomes very high if the engine is not operated for a long time. As a result, the fuel tank may be damaged. Therefore, even when the internal pressure of the fuel tank 10 is equal to or higher than a predetermined value when the engine is stopped, the evaporated fuel in the fuel tank 10 may flow into the canister 12. In this case, for example, by providing a passage bypassing the tank passage valve 24 on the tank passage 22 and providing a mechanical pressure regulating valve that opens at a predetermined pressure on the passage, the fuel tank 10 can be depressurized. it can.

  In the first and second embodiments, when the heater 38 heats the catalyst 34 when the key is turned on, the temperature sensor 36 is used to determine that the catalyst temperature has reached the activation determination value. The heating may be set to be performed for a predetermined time. Thereby, in the first embodiment, the temperature sensor 36 can be omitted.

  In the second embodiment, the concentration of the evaporated fuel is adjusted based on the temperature of the catalyst 34 measured by the temperature sensor 36. However, the concentration of the evaporated fuel supplied to the catalyst module 16 may be directly measured. . In this case, for example, the concentration of the evaporated fuel can be measured by installing an A / F sensor in the vicinity of the inlet of the catalyst module 16 instead of the temperature sensor 36.

DESCRIPTION OF SYMBOLS 10 Fuel tank 12 Canister 14 Electric pump 16 Catalyst module 17 Pressure sensor 18 Cap 19 Cap sensor 20 ECU
22 Tank passage 24 Tank passage valve 26 Air passage 28 Air filter 30 Catalyst passage 32 Catalyst passage valve 34 Catalyst 36 Temperature sensor 38 Heater 40 Exhaust pipe 42 Tank fuel purge passage 44 Tank fuel purge passage valve (open / close valve)
46 Intake pipe 48 Throttle valve 50 Air filter 52 A / F sensor 60 Divider 62 Branch passage C Adsorbent

Claims (5)

A fuel tank for storing fuel to be supplied to the internal combustion engine, and a canister capable of adsorbing the evaporated fuel in the fuel tank, and at least the evaporated fuel generated in the fuel tank when refueling the fuel tank An evaporative fuel processing apparatus for supplying to the canister,
A pump for desorbing evaporated fuel from the canister by introducing air into the canister;
A catalyst capable of combusting evaporated fuel desorbed from the canister;
A pressure sensor capable of measuring the internal pressure of the fuel tank;
A tank fuel purge passage that is provided as a passage that communicates the fuel tank and the intake pipe of the internal combustion engine, and that the passage is communicated and shut off by an on-off valve installed in the passage;
When the internal pressure of the internal combustion engine is detected by the pressure sensor and the internal pressure of the fuel tank is not less than a predetermined value, the on-off valve is opened, and the internal pressure of the fuel tank is not more than the predetermined value The evaporative fuel processing device is characterized in that the on-off valve is controlled to be closed. It is an evaporative fuel processing apparatus of Claim 1, Comprising:
A tank passage valve for communicating and blocking a tank passage for communicating the fuel tank and the canister;
An evaporative fuel processing apparatus, wherein the tank passage valve is controlled to be in an open state when refueling and to be closed when not refueling. The evaporative fuel processing device according to claim 1 or 2,
A shunt capable of bypassing the atmosphere introduced by the pump before the catalyst without passing through the canister;
The diverter is capable of diverting the atmosphere to an arbitrary flow rate, and adjusts the concentration of evaporative fuel supplied to the catalyst. It is an evaporative fuel processing apparatus as described in any one of Claims 1 thru | or 3, Comprising:
A catalyst passage valve for communicating and blocking a catalyst passage for communicating the canister and the catalyst;
A heater for heating the catalyst;
And evaporative fuel is burned by the catalyst, the temperature of the catalyst is raised to an activation temperature by the heater, the catalyst passage valve is opened, and the pump is driven. Processing equipment. It is an evaporative fuel processing apparatus as described in any one of Claim 1 thru | or 4, Comprising:
An evaporation characterized by supplying evaporated fuel generated in the fuel tank to an intake pipe when the internal pressure of the fuel tank is not less than a predetermined value and A / F feedback control is possible during operation of the internal combustion engine. Fuel processor.

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