JP2010270618A - Evaporative fuel processing equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inhibit evaporated fuel produced in a fuel tank from being adsorbed by a canister. <P>SOLUTION: An evaporated fuel treatment device includes a fuel tank (300) storing fuel, the canister (400) connected to the fuel tank through an evaporated fuel passage (360), a fuel trapper (500) provided separately from the fuel tank and temporarily storing the fuel, a first communication passage (510) providing the communication between the lower part of the fuel tank and the lower part of the fuel trapper, and a second communication passage (520) providing the communication between the upper space of the fuel trapper and the atmosphere. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a technical field of an evaporative fuel processing apparatus provided in, for example, an internal combustion engine.

  A canister (or adsorber) containing an adsorbent such as activated carbon as an evaporative fuel treatment device for preventing the evaporative fuel (hereinafter referred to as “vapor”) generated in a fuel tank of an internal combustion engine from being released to the atmosphere. There is known a device for connecting a fuel tank to a fuel tank (see, for example, Patent Documents 1 and 2). For example, Patent Document 1 includes a main tank and a sub-tank, and a communication path that allows these to communicate with each other, a first communication path that communicates a gas phase portion of the main tank and a liquid phase portion of the sub tank, and a gas phase of the sub tank. An apparatus that promotes the liquefaction of the evaporated fuel by disposing the portion and the second communication passage that communicates the liquid phase portion of the main tank and communicating the sub tank and the canister through the charge passage is disclosed. Further, Patent Document 2 includes a fuel tank and a sub tank placed in a lower temperature environment than the fuel tank. The evaporated fuel is led from the upper space of the fuel tank into the sub tank and liquefied, and the liquefied fuel is supplied. An apparatus configured to return to a fuel tank is disclosed.

JP 2007-176289 A Japanese Patent No. 3659005

  However, the apparatus disclosed in Patent Documents 1 and 2 described above has a technical problem that the effect of liquefying the evaporated fuel becomes small when the temperature difference between the main tank or the fuel tank and the sub tank is small. is there. In addition, these apparatuses have a technical problem that their structures are relatively complicated, for example, a plurality of communication passages for communicating the main tank or the fuel tank and the sub tank are required.

  The present invention has been made in view of, for example, the above-described problems. For example, the evaporative fuel treatment can suppress the evaporative fuel generated in the fuel tank from being adsorbed to the canister with a relatively simple configuration. It is an object to provide an apparatus.

  In order to solve the above problems, the fuel vapor processing apparatus of the present invention is provided separately from a fuel tank for storing fuel, a canister connected to the fuel tank via a fuel vapor passage, and the fuel tank, A fuel trapper capable of temporarily storing fuel; a first communication path that communicates the lower part of the fuel tank; and a lower part of the fuel trapper; and a second communication path that communicates the upper space of the fuel trapper and the atmosphere. With.

  The evaporative fuel processing apparatus of the present invention is mounted on a vehicle, for example, and includes, for example, a fuel tank that stores fuel of an internal combustion engine, and a canister that can adsorb evaporative fuel (that is, vapor) generated in the fuel tank. The fuel tank and the canister are connected via an evaporative fuel passage. The evaporative fuel passage is typically provided with a block valve that opens when the pressure in the fuel tank is equal to or higher than a predetermined valve opening pressure, and the pressure in the fuel tank is equal to or higher than the predetermined valve opening pressure. Sometimes vapor flows from the fuel tank into the canister and is adsorbed.

  In particular, the present invention includes a fuel trapper, a first communication path, and a second communication path. The fuel trapper is a container provided separately from the fuel tank, for example, above the fuel tank and capable of temporarily storing fuel. For example, the fuel trapper is disposed in a low environment where the temperature is lower than that of the fuel tank. The first communication path is formed of, for example, a tubular member, and communicates the lower part of the fuel tank and the lower part of the fuel trapper. For example, the first communication path is configured such that one end side is connected to the lower surface of the fuel trapper and the other end side is disposed near the lower surface of the fuel tank through the upper surface of the fuel tank. For this reason, the end of the first communication passage on the fuel tank side is immersed in the fuel stored in the fuel tank. In other words, the end of the first communication passage on the fuel tank side is disposed in the fuel in the fuel tank (in other words, in the liquid phase). The second communication path is formed of, for example, a tubular member, and communicates the upper space of the fuel trapper with the atmosphere. For example, the second communication path has one end connected to the upper part of the fuel trapper and the other end open to the atmosphere. Here, the “upper space of the fuel trapper” is an upper space in the fuel trapper, and means a gas phase space formed above the fuel temporarily stored in the fuel trapper.

  Thus, for example, when the temperature of the fuel in the fuel tank rises due to the outside air temperature or the exhaust heat of the internal combustion engine, and the pressure in the fuel tank rises due to the generation of vapor, the fuel stored in the fuel tank A part can be transferred to the fuel trapper via the first communication pipe. Therefore, the pressure in the fuel tank can be reduced, and the vapor in the fuel tank can be prevented from flowing into the canister, that is, the vapor can be prevented from being adsorbed by the canister. Furthermore, the fuel transferred to the fuel trapper can be returned to the fuel tank as the pressure in the fuel tank decreases, and the fuel in the fuel tank can be cooled by the fuel returned from the fuel trapper. As described above, the fuel trapper is disposed in a low environment where the temperature is lower than that of the fuel tank, and the fuel transferred from the fuel tank to the fuel trapper is cooled in the fuel trapper. Therefore, the generation of vapor in the fuel tank can be suppressed. Thereby, it can suppress that vapor is adsorbed to a canister. In addition, according to the present invention, the fuel tanker has a relatively simple configuration in which the fuel trapper, the first communication path, and the second communication path are provided to the fuel tank. Various specifications such as weight, cost, and space can be satisfied, which is very advantageous in practice.

  As described above, according to the present invention, it is possible to prevent the evaporated fuel (ie, vapor) generated in the fuel tank from being adsorbed by the canister. Furthermore, since it has a relatively simple configuration, it is very advantageous in practice.

  In one aspect of the evaporated fuel processing apparatus of the present invention, the fuel vapor processing apparatus further includes a blocking valve that is provided in the evaporated fuel passage and opens when the pressure in the fuel tank is equal to or higher than a predetermined valve opening pressure.

  According to this aspect, when the pressure in the fuel tank is less than the predetermined valve opening pressure, the block valve is closed and the evaporated fuel passage is blocked, so that the communication between the fuel tank and the canister can be blocked. . Therefore, when the pressure in the fuel tank is lower than the predetermined valve opening pressure, the fuel in the fuel tank is transferred to the fuel trapper while preventing the vapor in the fuel tank from flowing into the canister by the blocking valve. Can do. Therefore, it is possible to more reliably suppress the vapor in the fuel tank from flowing into the canister.

  In another aspect of the evaporated fuel processing apparatus of the present invention, the fuel trapper is provided in a low temperature portion having a temperature lower than that of a portion where the fuel tank is provided in a vehicle on which the evaporated fuel processing apparatus is mounted.

  According to this aspect, the fuel transferred from the fuel tank to the fuel trapper can be reliably cooled in the fuel trapper. Therefore, the fuel cooled in the fuel trapper is returned to the fuel tank, so that the fuel in the fuel tank can be cooled more reliably by the fuel returned from the fuel trapper. Therefore, the generation of vapor in the fuel tank can be more reliably suppressed.

  In another aspect of the fuel vapor processing apparatus of the present invention, the second communication path communicates with the atmosphere via the canister.

  According to this aspect, it is possible to suppress or prevent the vapor from being released into the atmosphere via the second communication path.

  In the aspect in which the second communication path communicates with the atmosphere via the canister, the fuel trapper and the canister are provided in the second communication path to communicate the fuel trapper with the canister when the valve is opened, and with the fuel trapper and the canister when the valve is closed. There may be further provided an on-off valve that blocks communication with the.

  In this case, for example, when a system including a canister and a fuel trapper is used as an inspection target system and an inspection for detecting an abnormality such as perforation is performed, one of the canister and the fuel trapper having an abnormality is identified. That is, it is possible to determine which of the canister and the fuel trapper is abnormal.

  In the aspect further including the on-off valve described above, the pressure detecting means for detecting the pressure in the fuel tank and the communication between the fuel trapper and the canister are detected by the pressure detecting means in a state where the on-off valve is shut off. And a first abnormality determining means for determining whether or not an abnormality has occurred in the fuel tank based on the measured pressure.

  In this case, it is possible to avoid erroneous detection due to fluctuations in the liquid level of the fuel in the fuel tank when the perforated detection is performed using the system including the fuel tank as the inspection target system.

  In another aspect of the evaporated fuel processing apparatus of the present invention, a liquid level detecting means for detecting a liquid level of the fuel in the fuel trapper, and the liquid level detected by the liquid level detecting means. And a second abnormality determining means for determining whether or not an abnormality has occurred in the fuel tank.

  According to this aspect, an abnormality such as a hole in the fuel tank is generated based on the liquid level detected by the liquid level detection means without measuring the pressure in the fuel tank. It becomes possible to detect.

  The effect | action and other gain of this invention are clarified from the form for implementing invention demonstrated below.

It is a mimetic diagram of a vehicle provided with an evaporation fuel processing device concerning a 1st embodiment. It is a flowchart which shows the motion of the fuel by the change of a tank internal pressure. It is a schematic diagram of the vehicle provided with the evaporative fuel processing apparatus which concerns on 2nd Embodiment. It is a flowchart which shows the flow of canister side perforation detection in 2nd Embodiment. It is a schematic diagram of the vehicle provided with the evaporative fuel processing apparatus which concerns on 3rd Embodiment. It is a flowchart which shows the flow of canister side perforation detection in 3rd Embodiment. It is a schematic diagram of the vehicle provided with the evaporative fuel processing apparatus which concerns on 4th Embodiment. It is a flowchart which shows the flow of the tank side perforation detection in 4th Embodiment. It is a schematic diagram of the vehicle provided with the evaporative fuel processing apparatus which concerns on 5th Embodiment. It is a flowchart which shows the flow of perforation detection in 5th Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<First Embodiment>
The evaporated fuel processing apparatus according to the first embodiment will be described with reference to FIGS. 1 and 2.

  First, an overall configuration of a vehicle provided with an evaporated fuel processing apparatus according to the present embodiment will be described with reference to FIG.

  FIG. 1 is a schematic view of a vehicle equipped with an evaporated fuel processing apparatus according to this embodiment.

  In FIG. 1, a vehicle 10 provided with the evaporated fuel processing apparatus according to the present embodiment includes an engine 200, a motor generator 600, and an ECU 100.

  The vehicle 10 is configured as a so-called parallel type hybrid vehicle in which an engine 200 and a motor generator 600 that functions as an electric motor and a generator are mounted as driving sources for traveling. Engine 200 and motor generator 600 are connected to each other via a power transmission mechanism (not shown). The vehicle 10 performs HV (hybrid vehicle) traveling that travels by the driving force of both the engine 200 and the motor generator 600 and EV (Electric Vehicle) traveling that travels by the driving force of the motor generator 600 only when the engine 200 is stopped. It can be selectively performed. The vehicle 10 may be a vehicle that uses only the engine 200 as a drive source.

  The engine 200 is a gasoline engine configured to function as one of the drive sources of the vehicle 10 and using gasoline as fuel. The engine 200 burns an air-fuel mixture of fuel and intake air (that is, air guided from the outside) inside the cylinder, and converts the internal piston motion generated according to the explosive force into a rotational motion, thereby converting the vehicle 10. Is configured to be drivable. The engine 200 is not limited to a gasoline engine, and may be a diesel engine using light oil as a fuel or a bi-fuel engine that can use a mixed fuel of alcohol and gasoline.

  The engine 200 is provided with an intake passage 210 for guiding intake air from the outside to the inside of the cylinder. An air cleaner 220 is disposed in the intake passage 210 to purify air sucked from the outside. A throttle valve 212 for adjusting the amount of intake air into the cylinder is disposed on the downstream side (cylinder side) of the air cleaner 220 in the intake passage 210. In the engine 200, the intake air sucked from the outside by the intake passage 210 and the fuel injected from the injector 214 which is a fuel injection device are mixed (that is, an air-fuel mixture is formed), and this air-fuel mixture is combusted. .

  The ECU 100 is an electronic control unit that includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like, and is configured to be able to control the entire operation of the vehicle 10.

  The vehicle 10 further includes a fuel tank 300, a canister 400, and a fuel trapper 500.

  The fuel tank 300 is a fuel tank for storing the fuel of the engine 200. The fuel tank 300 is provided with an inlet pipe 310 that is a pipe for supplying fuel into the fuel tank 300. A fuel cap 312 is detachably attached to the oil filler port 311 of the inlet pipe 310. A check valve 313 that prevents the fuel in the fuel tank 300 from flowing back through the inlet pipe 310 and flowing from the fuel tank 300 toward the fuel filler 311 is provided at the end of the inlet pipe 310 opposite to the fuel filler 311. It has been. A vent line 320 is connected in the vicinity of the oil filler port 311 of the inlet pipe 310. The vent line 320 is provided in order to return the evaporated fuel in the fuel tank 300 to the vicinity of the fuel inlet 311 of the inlet pipe 310 and reduce the amount of air entering the fuel tank 300 from the fuel inlet 11 during fueling.

  A fuel pump 330 and a remaining amount sensor 340 are disposed in the fuel tank 300. The fuel pump 330 is a pump device configured to suck up fuel stored in the fuel tank 300. A feed pipe 350 reaching the injector 214 of the engine 200 is connected to the fuel pump 330, and fuel sucked up by the fuel pump 330 is supplied to the injector 214 via the feed pipe 350. The remaining amount sensor 340 is a float type liquid level sensor, and is configured to detect the remaining amount of fuel in the fuel tank 300 by quantifying it. The remaining amount sensor 340 is electrically connected to the ECU 100. The remaining amount of fuel detected by the remaining amount sensor 340 is referred to by the ECU 100 at a constant or indefinite period.

  Connected to the upper part of the fuel tank 300 is an evaporation line 360 that is an example of an “evaporated fuel passage” according to the present invention, which communicates a canister 400 described later and a fuel liquid level upper space in the fuel tank 300. An ORVR valve (Onboard refueling vapor recovery valve) 371 and a COV (Cut Off Valve) 372 are provided at a connection portion between the evaporation line 360 and the fuel tank 300. The ORVR valve 371 is configured to close when the liquid level rises during refueling, and to block communication between the evaporation line 360 and the fuel tank 300. Further, the ORVR valve 371 is configured to block the communication between the evaporation line 360 and the fuel tank 300 even when the vehicle falls or the like, and the fuel in the fuel tank 300 does not leak to the outside via the evaporation line 360. ing. The COV 372 is arranged in parallel with the ORVR valve 371 and is configured to block communication between the evaporation line 360 and the fuel tank 300 when the liquid level rises further than the ORVR valve 371. The COV 372 maintains its open state even after the ORVR valve 371 is closed when the liquid level rises during refueling. However, the COV 372 is closed when the liquid level reaches the COV 372 due to the fluctuation of the liquid level caused by turning of the vehicle. The communication between the evaporation line 360 and the fuel tank 300 is cut off, and the fuel in the fuel tank 300 is not leaked to the outside through the evaporation line 360.

  The evaporation line 360 is provided with a block valve 370. The blocking valve 370 is a valve device configured to be able to open and block the evaporation line 360 by an opening / closing operation. When the blocking valve 370 is in the closed state, the evaporation line 360 is blocked and the communication between the fuel tank 300 and the canister 400 is blocked. The block valve 370 is configured to open when the pressure in the fuel tank 300 (hereinafter referred to as “tank internal pressure” as appropriate) is equal to or higher than a predetermined valve opening pressure. The blocking valve 370 is connected to the ECU 100, and its opening / closing operation is controlled by the ECU 100.

  The canister 400 is an adsorption device provided with an adsorbent 410 such as activated carbon capable of adsorbing and holding the evaporated fuel (that is, vapor) generated in the fuel tank 300 therein. The canister 400 is connected to three types of pipes, the above-described evaporation line 360, the atmosphere communication pipe 420, and the purge pipe 430.

  The atmosphere communication pipe 420 is a tubular member that communicates with the space outside the vehicle 10 (in other words, the atmosphere), and is connected to the canister 400 via a key-off pump 450 described later. When the purge control valve 440, which will be described later, is closed and the above-described blocking valve 370 is opened, the atmosphere communication pipe 420 is vaporized by the adsorbent 410 out of the gas flowing into the canister 400 via the evaporation line 360. Clean air remaining after the adsorption is led out of the vehicle, and when the purge control valve 440 is opened and the closing valve 370 is closed, the outside air is led from outside the vehicle to the canister 400.

  The key-off pump 450 is a pump device that is used as appropriate when performing inspection for detecting abnormalities such as perforations (hereinafter referred to as “perforation detection” as appropriate) using the canister 400, the fuel tank 300, etc. as an inspection target system. It is. “Perforated” means that a hole is formed in the system to be inspected to allow gas inside to leak to the outside.

  The key-off pump 450 is provided with a pressure sensor 460. The pressure sensor 460 is a pressure sensor configured to be able to detect the pressure on the canister 400 side in the key-off pump 450. The pressure sensor 460 is electrically connected to the ECU 100. The pressure detected by the pressure sensor 460 is referred to by the ECU 100 at a constant or indefinite period.

  In the perforated detection, for example, first, air on the canister 400 side is exhausted to the outside of the vehicle through the atmosphere communication pipe 420 by the key-off pump 450, and the pressure of the inspection target system including the canister 400 is made negative. Next, after the key-off pump 450 is stopped and the communication between the canister 400 and the atmosphere communication pipe 420 is shut off, it is determined whether or not an abnormality such as a hole has occurred based on the pressure change of the inspection target system. The

  The purge pipe 430 is a purge gas passage having one end connected to the lower side of the canister 400 and the other end connected to the downstream side of the throttle valve 212 in the intake passage 210.

  Here, the “purge gas” is a mixture of outside air appropriately guided through the atmosphere communication pipe 420 and vapor adsorbed and held on the adsorbent 410 (that is, outside air itself if the amount of adsorption of the vapor is zero). It is. Such purge gas is supplied to the intake passage 210 via the purge pipe 430 when the engine 200 is in operation, and vapor contained in the purge gas is used for combustion in the engine 200. In the following, a series of processes in which the vapor adsorbed on the canister 400 is used for combustion in the engine 200 as described above is appropriately referred to as “purge process”.

  The purge pipe 430 is provided with a purge control valve 440 that is a VSV (Vacuum Switching Valve). The valve body of the purge control valve 440 is a directional concept based on the flow direction of the purge gas when the engine 200 is not in operation, the upstream side and the downstream side of the purge control valve 440 (the upstream side and the downstream side in this case). Thus, the upstream side means the canister 440 side, and the downstream side means the intake passage 210 side) and is biased by an elastic body such as a coil spring so as to stop at a blocking position where communication with the upstream side is blocked. On the other hand, when the engine 200 is in an operating state, a negative pressure is formed in the intake passage 210 mainly during the intake stroke. Due to this negative pressure, the valve body position of the purge control valve 440 as VSV is changed from the shut-off position, and the upstream side and the downstream side of the purge control valve 440 communicate with each other. As a result, the outside air is guided by the engine negative pressure through the atmosphere communication pipe 420, and the outside air is appropriately mixed with the vapor held in the adsorbent 410 on the way to the purge pipe 430, thereby The purge gas is supplied to the intake passage 210 via the purge pipe 430. The purge control valve 440 is configured as a VSV in the present embodiment, but the configuration is not limited to the VSV. The purge control valve 440 may be configured as, for example, an electromagnetically controlled valve device including a valve body that is driven by an electromagnetic actuator or the like.

  The fuel trapper 500 is a container provided above the fuel tank 300 and capable of temporarily storing fuel. The fuel trapper 500 is a low-temperature part (for example, in a body shell or the like) in the vehicle 10 where the temperature is lower than a part (for example, an engine compartment (hereinafter referred to as “encopa” as appropriate) or a floor) where the fuel tank 300 is disposed. In the passenger compartment). A first communication path 510 and a second communication path 520 are connected to the fuel trapper 500.

  The first communication path 510 is a tubular member that allows the lower part of the fuel tank 300 and the lower part of the fuel trapper 500 to communicate with each other. The first communication path 510 is configured such that one end side is connected to the lower surface of the fuel trapper 500 and the other end side is disposed near the lower surface of the fuel tank 300 through the upper surface of the fuel tank 300. For this reason, the other end of the first communication passage 510 is immersed in the fuel stored in the fuel tank 300.

  The second communication path 520 is a tubular member that communicates the upper space of the fuel trapper 500 with the atmosphere. The second communication path 520 has one end connected to the upper part of the fuel trapper 500 and the other end open to the atmosphere.

  Next, the effects of the fuel trapper 500, the first communication path 510, and the second communication path 520, which are configurations unique to the present embodiment, will be described with reference to FIG. 2 in addition to FIG.

  FIG. 2 is a flowchart showing the movement of the fuel due to the change in the tank internal pressure.

  1 and 2, the movement of the fuel stored in the fuel tank 300 differs depending on whether or not the tank internal pressure increases (step S110). The tank internal pressure rises when the temperature of the fuel in the fuel tank 300 rises due to, for example, the outside air temperature or the exhaust heat of the engine 200 and vapor is generated.

  When the tank internal pressure increases (step S110: Yes), a part of the fuel stored in the fuel tank 300 is transferred to the fuel trapper 500 through the first communication pipe 510 (step S120). That is, the fuel in the fuel tank 300 is pushed up into the fuel trapper 500 through the first communication path 510 by the increased tank internal pressure. Since the fuel trapper 500 is communicated with the atmosphere by the second communication path 520, the pressure in the fuel trapper 500 is lower than the increased tank internal pressure.

  The transfer of fuel from the fuel tank 300 to the fuel trapper 500 is continued until the pressure difference between both ends of the first communication pipe 510 disappears. That is, such fuel transfer is performed while maintaining a pressure balance between the tank internal pressure and the pressure of the fuel transferred into the fuel trapper 500.

  Therefore, the tank internal pressure decreases when a part of the fuel in the fuel tank 300 is transferred to the fuel trapper 500. Therefore, the blocking valve 370 is opened and the vapor in the fuel tank 300 can be prevented from flowing into the canister 400, that is, the vapor can be prevented from being adsorbed by the adsorbent 410 of the canister 400. .

  Next, the fuel transferred to the fuel trapper 500 is cooled (step S150). As described above, since the fuel trapper 500 is disposed in the low temperature portion of the vehicle 10 where the temperature is lower than the portion where the fuel tank 300 is disposed, the fuel transferred from the fuel tank 300 to the fuel trapper 500 is Cooled in the fuel trapper 500. Thereafter, the fuel cooled in the fuel trapper 500 returns to the fuel tank 300 via the first communication pipe 510 as the tank internal pressure decreases (see also step S130 described later). They are mixed (see also step S140 described later). Therefore, the fuel in the fuel tank 300 can be cooled by the fuel cooled in the fuel trapper 500. Therefore, the generation of vapor in the fuel tank 300 can be suppressed.

  Note that a cooling unit that more actively cools the fuel trapper 500, such as a cooling unit that cools the fuel trapper 500 by applying traveling wind to the fuel trapper 500 while the vehicle 10 is traveling, may be provided. In this case, the fuel transferred into the fuel trapper 500 can be cooled more reliably, and the generation of vapor in the fuel tank 300 can be more reliably suppressed.

  On the other hand, when the tank internal pressure has not increased (step S110: No), the movement of the fuel stored in the fuel tank 300 differs depending on whether the tank internal pressure has decreased (step S130). The internal pressure of the tank decreases as the temperature of the fuel in the fuel tank 300 decreases and the vapor condenses.

  When the tank internal pressure decreases (step S130: Yes), the fuel transferred into the fuel trapper 500 as described above is returned to the fuel tank 300 through the first communication pipe 510 (step S140). The return of the fuel from the fuel trapper 500 to the fuel tank 300 is caused by the pressure inside the tank and the pressure of the fuel transferred into the fuel trapper 500, as in the case of the fuel transfer from the fuel tank 300 to the fuel trapper 500 described above. It is done while balancing the pressure. Therefore, as described above, the fuel in the fuel tank 300 can be cooled by the fuel cooled in the fuel trapper 500.

  When the tank internal pressure has not decreased (that is, the tank internal pressure has not changed) (step S130: Yes), the fuel is not moved between the fuel tank 300 and the fuel trapper 500.

  As described above, according to the present embodiment, since the fuel trapper 500, the first communication path 510, and the second communication path 520 are provided, the temperature of the fuel in the fuel tank 300 increases and the tank internal pressure increases. In this case, a part of the fuel in the fuel tank 300 can be transferred to the fuel trapper 500 via the first communication pipe 510. Therefore, the vapor in the fuel tank 300 can be prevented from flowing into the canister 400. Furthermore, the fuel cooled in the fuel trapper 500 can be returned to the fuel tank 300 as the tank internal pressure decreases. Therefore, the fuel in the fuel tank 300 can be cooled and the generation of vapor can be suppressed. In addition, according to the present embodiment, since the fuel trapper 500, the first communication path 510, and the second communication path 520 are provided to the fuel tank 300, the fuel tank 300 is mounted on the vehicle 10. For example, it is possible to satisfy various specifications such as weight, cost, and space, which is very advantageous in practice.

<Second Embodiment>
The evaporative fuel processing apparatus according to the second embodiment will be described with reference to FIGS. 3 and 4.

  FIG. 3 is a schematic view of a vehicle including the evaporated fuel processing apparatus according to the second embodiment. In FIG. 3, the same reference numerals are given to the same components as those according to the first embodiment shown in FIG. 1, and the description thereof will be omitted as appropriate.

  In FIG. 3, the evaporative fuel processing apparatus according to the second embodiment includes the second communication path 522 instead of the second communication path 520 (see FIG. 1) in the first embodiment described above. Unlike the fuel vapor processing apparatus according to the embodiment, the other points are configured in substantially the same manner as the fuel vapor processing apparatus according to the first embodiment described above.

  In FIG. 3, the second communication passage 522 is a tubular member that allows the upper space of the fuel trapper 500 to communicate with the atmosphere. The second communication path 522 has one end connected to the upper portion of the fuel trapper 500 and the other end connected to the evaporation line 360. That is, the second communication path 522 is configured to communicate with the atmosphere via the canister 400. That is, in the present embodiment, the upper space of the fuel trapper 500 communicates with the atmosphere via the second communication path 522, the evaporation line 360, the canister 400, and the atmosphere communication pipe 420.

  As described above, in the present embodiment, in particular, the second communication path 522 communicates with the atmosphere via the canister 400, so that vapor can be suppressed or prevented from being released into the atmosphere via the second communication path 522. That is, according to the present embodiment, the vapor flowing from the fuel trapper 500 side to the atmosphere side through the second communication path 522 can be adsorbed to the adsorbent 410 of the canister 400, so that the vapor is almost or completely released into the atmosphere. Can be eliminated.

  Furthermore, according to the present embodiment, it is possible to perform perforation detection using the canister 400 and the fuel trapper 500 as one inspection target system. Hereinafter, perforation detection performed by using the canister 400 and the fuel trapper 500 as one inspection target system is appropriately referred to as “canister side perforation detection”.

  FIG. 4 is a flowchart showing the flow of canister side hole detection in this embodiment.

  In FIG. 4, first, the ECU 100 determines whether or not an execution condition capable of performing canister side hole detection (ie, canister side hole detection execution condition) is satisfied (step S210). That is, first, the ECU 100 determines whether or not the canister side perforation detection execution condition (for example, the engine 200 is stopped, the purge control valve 440 and the closing valve 370 are closed, etc.) is satisfied. Determine.

  If it is determined that the canister side perforation detection execution condition is not satisfied (step S210: No), for example, the ECU 100 determines again whether the canister side perforation detection execution condition is satisfied after a predetermined time. (Step S210).

  On the other hand, if it is determined that the canister side hole detection execution condition is satisfied (step S210: Yes), the canister side hole detection is started by the ECU 100 (step S220).

  When the canister side perforation detection is started, first, the key-off pump 450 is operated, and a negative pressure is introduced into the inspection target system (step S230). In other words, under the control of the ECU 100, the air on the canister 400 side is exhausted outside the vehicle through the atmospheric communication pipe 420 by the key-off pump 450, and the pressure of the inspection target system including the canister 200 and the fuel trapper 500 is made negative.

  Next, the key-off pump 450 is stopped by the ECU 100, and the system to be inspected is held in a negative pressure state (step S240). That is, the key-off pump 450 is stopped under the control of the ECU 100, and the communication between the canister 400 and the atmosphere communication pipe 420 is blocked.

  Next, it is determined by the ECU 100 whether or not the pressure in the inspection target system has changed (step S250). At this time, for example, the ECU 100 determines whether or not the pressure in the inspection target system has changed based on the pressure detected by the pressure sensor 460 provided in the key-off pump 450.

  When it is determined that the pressure in the inspection target system has changed (step S250: Yes), the ECU 100 determines that the inspection target system is abnormal (step S260). That is, for example, when it is determined that the pressure in the inspection target system has decreased, it is determined that an abnormality such as a hole has occurred in the inspection target system.

  On the other hand, when it is determined that the pressure in the inspection target system has not changed (step S250: No), the ECU 100 determines that the inspection target system is normal (step S270).

<Third Embodiment>
The evaporative fuel processing apparatus according to the third embodiment will be described with reference to FIGS. 5 and 6.

  FIG. 5 is a schematic diagram of a vehicle including the evaporated fuel processing apparatus according to the third embodiment. 5, the same reference numerals are given to the same components as those according to the second embodiment shown in FIG. 3, and the description thereof will be omitted as appropriate.

  In FIG. 5, the evaporated fuel processing apparatus according to the third embodiment differs from the evaporated fuel processing apparatus according to the second embodiment described above in that the second communication passage 522 further includes an on-off valve 530. Is configured in substantially the same manner as the evaporated fuel processing apparatus according to the second embodiment described above.

  In FIG. 5, the on-off valve 530 is provided in the second communication path 522, and allows the fuel trapper 500 and the canister 400 to communicate with each other when the valve is opened, and can block communication between the fuel trapper 500 and the canister 400 when the valve is closed. It is the valve apparatus comprised in this.

  According to the present embodiment, since the on-off valve 530 is provided, the perforation detection is performed by using the canister 400 and the fuel trapper 500 as one inspection target system by opening the on-off valve 530. In addition, by making the on-off valve 530 closed, it is possible to detect perforation using only the canister 400 out of the canister 400 and the fuel trapper 500 as an inspection target system. Therefore, when the canister 400 and the fuel trapper 500 are used as one inspection target system and the canister side perforation detection is performed, if it is determined that there is an abnormality in the inspection target system, the canister 400 and the fuel trapper 500 are abnormal. It is possible to specify one of the occurrences of the fuel gas (i.e., to determine which of the canister 400 and the fuel trapper 500 is abnormal).

  FIG. 6 is a flowchart showing the flow of canister side hole detection in this embodiment. In FIG. 6, the same reference numerals are assigned to the same operation processes as those according to the second embodiment shown in FIG. 4, and description thereof will be omitted as appropriate.

  In FIG. 6, after the system to be inspected (that is, the canister 400 and the fuel trapper 500) is maintained in a negative pressure state (step S240), the ECU 100 determines whether or not the pressure in the system to be inspected has changed. (Step S250).

  If it is determined that the pressure in the inspection target system has changed (step S250: Yes), the on-off valve 530 is closed by the ECU 100 (step S360).

  Thereafter, ECU 100 determines whether or not the pressure in canister 400 has changed (step S370). At this time, the ECU 100 determines whether or not the pressure in the canister 400 is changed based on the pressure detected by the pressure sensor 460 provided in the key-off pump 450, for example.

  When it is determined that the pressure in the canister 400 is changing (step S370: Yes), the ECU 100 determines that the canister 400 is abnormal (step S380). That is, for example, when it is determined that the pressure in the canister 400 has decreased, it is determined that an abnormality such as a hole in the canister 400 has occurred.

  On the other hand, when it is determined that the pressure in the canister 400 has not changed (step S370: No), the ECU 100 determines that the canister 400 is normal and the fuel trapper 500 is abnormal (step S390). . That is, for example, when it is determined that the pressure in the canister 400 has not decreased, it is determined that an abnormality such as a hole in the fuel trapper 500 has occurred.

<Fourth embodiment>
The evaporative fuel processing apparatus according to the fourth embodiment will be described with reference to FIGS.

  FIG. 7 is a schematic view of a vehicle provided with the evaporated fuel processing apparatus according to the fourth embodiment. In FIG. 7, the same components as those in the third embodiment shown in FIG. 5 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

  In FIG. 7, the evaporated fuel processing apparatus according to the fourth embodiment further includes a pressure sensor 345, and the ECU 100 causes the pressure sensor 345 to communicate with the fuel trapper 500 and the canister 400 while being disconnected by the on-off valve 530. Unlike the evaporated fuel processing apparatus according to the third embodiment described above, it is determined whether or not an abnormality has occurred in the fuel tank 300 based on the detected pressure. The fuel vapor processing apparatus according to the third embodiment is configured in substantially the same manner.

  In FIG. 7, a pressure sensor 345 is a pressure sensor that is provided on the upper surface of the fuel tank 300 and configured to detect the pressure in the fuel tank 300 (that is, the tank internal pressure). The pressure sensor 345 is electrically connected to the ECU 100. The tank internal pressure detected by the pressure sensor 345 is referred to by the ECU 100 at a constant or indefinite period. The pressure sensor 345 is an example of the “pressure detection means” according to the present invention.

  The ECU 100 determines whether an abnormality such as a perforation has occurred in the fuel tank 300 based on the pressure detected by the pressure sensor 345 in a state where the communication between the fuel trapper 500 and the canister 400 is blocked by the on-off valve 530. It is possible to determine whether or not. That is, in the present embodiment, the ECU 100 is configured to be able to function as “first abnormality determination means” according to the present invention.

  According to the present embodiment, it is possible to avoid erroneous detection due to fluctuations in the liquid level of the fuel in the fuel tank 300 when performing perforation detection using a system including the fuel tank 300 as an inspection target system. It becomes. Hereinafter, perforation detection performed using the system including the fuel tank 300 as an inspection target system is appropriately referred to as “tank side perforation detection”.

  FIG. 8 is a flowchart showing a flow of tank side hole detection in the present embodiment.

  In FIG. 8, first, the ECU 100 determines whether or not an execution condition capable of performing tank-side perforation detection (that is, a tank-side perforation detection execution condition) is satisfied (step S410). That is, first, the ECU 100 determines whether a tank side perforation detection execution condition (for example, the engine 200 is stopped, the purge control valve 440 is in a closed state, etc.) is satisfied.

  When it is determined that the tank-side perforation detection execution condition is not satisfied (step S410: No), for example, the ECU 100 determines again whether the tank-side perforation detection execution condition is satisfied after a predetermined time. (Step S410).

  On the other hand, when it is determined that the tank side hole detection execution condition is satisfied (step S410: Yes), tank side hole detection is started by the ECU 100 (step S420).

  When tank side perforation detection is started, first, the blocking valve 370 is opened, and the on-off valve 530 is closed (step S430). That is, when the ECU 100 starts detection of perforation on the tank side, the canister 400 and the fuel tank 300 communicate with each other via the block valve 370, and the communication between the fuel trapper 500 and the canister 400 is established by the on-off valve 530. The blocking valve 370 and the opening / closing valve 530 are controlled so as to be shut off.

  Next, the key-off pump 450 is activated, and negative pressure is introduced into the inspection target system (step S440). In other words, under the control of the ECU 100, the air on the fuel tank 300 side is exhausted outside the vehicle through the atmospheric communication pipe 420 by the key-off pump 450, and the pressure of the inspection target system including the fuel tank 300 is made negative.

  Next, the key-off pump 450 is stopped by the ECU 100, and the system to be inspected is held in a negative pressure state (step S450). That is, the key-off pump 450 is stopped under the control of the ECU 100, and the communication between the canister 400 and the atmosphere communication pipe 420 is blocked.

  Next, it is determined by the ECU 100 whether or not the pressure in the inspection target system has changed (step S460). At this time, for example, the ECU 100 determines whether or not the pressure in the inspection target system has changed based on the pressure detected by the pressure sensor 345 provided in the fuel tank 300.

  When it is determined that the pressure in the inspection target system has changed (step S460: Yes), the ECU 100 determines that the inspection target system is abnormal (step S470). That is, for example, when it is determined that the pressure in the inspection target system has decreased, it is determined that an abnormality such as a hole has occurred in the inspection target system.

  On the other hand, when it is determined that the pressure in the inspection target system has not changed (step S460: No), the ECU 100 determines that the inspection target system is normal (step S480).

  In the present embodiment, as described above, when the tank side perforation detection is performed, the on-off valve 530 is closed (step S430), so that the fuel between the fuel trapper 500 and the fuel tank 300 is closed. Therefore, the fluctuation of the fuel level in the fuel tank 300 can be reduced or prevented. Therefore, it is possible to avoid erroneous detection of an abnormality such as perforation due to fluctuations in the tank internal pressure due to fluctuations in the fuel level in the fuel tank 300.

<Fifth Embodiment>
An evaporated fuel processing apparatus according to the fifth embodiment will be described with reference to FIGS. 9 and 10.

  FIG. 9 is a schematic view of a vehicle provided with the evaporated fuel processing apparatus according to the fifth embodiment. 9, the same reference numerals are given to the same components as those according to the first embodiment shown in FIG. 1, and the description thereof will be omitted as appropriate.

  In FIG. 9, the evaporated fuel processing apparatus according to the fifth embodiment is different from the evaporated fuel processing apparatus according to the first embodiment described above in that it further includes a liquid level sensor 540, and other points are described above. The configuration is almost the same as that of the evaporated fuel processing apparatus according to the first embodiment.

  In FIG. 9, a liquid level sensor 540 is a float type liquid level sensor, and the level of fuel in the fuel trapper 500 (that is, the fuel level) can be detected numerically. It is configured. The liquid level sensor 540 is electrically connected to the ECU 100. The fuel level detected by the level sensor 540 is referred to by the ECU 100 at a constant or indefinite period. The liquid level sensor 540 is an example of the “liquid level detector” according to the present invention. In the present embodiment, the ECU 100 also functions as an example of the “second abnormality determination unit” according to the present invention.

  According to this embodiment, based on the fuel liquid level detected by the liquid level sensor 540, it is possible to perform perforation detection using the system including the fuel tank 300 as the inspection target system.

  FIG. 10 is a flowchart showing a flow of hole detection in the present embodiment.

  In FIG. 10, first, the ECU 100 determines whether or not the vehicle 10 is traveling (step S510).

  If it is determined that the vehicle is traveling (step S510: Yes), the ECU 100 determines whether the vehicle is traveling EV (step S520).

  If it is determined that the vehicle is traveling in EV (step S520: No), for example, the ECU 100 determines again whether the vehicle 10 is traveling again after a predetermined time (step S510).

  On the other hand, when it is determined that the vehicle is not traveling in the EV mode (step S520: Yes), the perforation detection is started by the ECU 100 (step S540). At this time, the ECU 100 determines whether or not an execution condition (for example, the purge control valve 440 is in a closed state) capable of performing perforation detection is satisfied, and the execution condition is satisfied. If so, start perforation detection.

  When it is determined that the vehicle is not traveling (step S510: No), the ECU 100 determines whether or not there is a change in the outside air temperature (step S530). The ECU 100 determines whether or not the outside air temperature detected by the outside air temperature sensor has changed from, for example, a reference temperature.

  When it is determined that there is no change in the outside air temperature (step S530: No), for example, the ECU 100 determines again whether the vehicle 10 is traveling again after a predetermined time (step S510).

  On the other hand, when it is determined that there is a change in the outside air temperature (step S530: Yes), perforation detection is started by the ECU 100 (step S540).

  That is, the detection of perforation in the present embodiment is based on the fact that the engine 200 is operating while the vehicle 10 is not traveling in EV (ie, in HV traveling), and the temperature of the fuel in the fuel tank 300 is exhausted by the exhaust heat of the engine 200 Is assumed to have risen (step S520: Yes), and the outside air temperature has changed (for example, the outside air temperature has risen), and the temperature of the fuel in the fuel tank 300 has changed (eg, rises). It is started when it is assumed that it is (step S530: Yes) (step S540).

  When the perforation detection is started, first, the fuel liquid level in the fuel trapper 500 is measured (step S550). That is, the ECU 100 refers to the fuel liquid level detected by the liquid level sensor 540.

  Next, ECU 100 determines whether or not there is a change in the fuel level in fuel trapper 500 (step 560). That is, the ECU 100 determines whether or not the fuel liquid level in the fuel trapper 500 has changed based on the fuel liquid level detected by the liquid level sensor 540.

  When it is determined that there is a change in the fuel liquid level (step S560: Yes), the ECU 100 determines that the inspection target system is normal (step 570).

  On the other hand, when it is determined that there is no change in the fuel liquid level (step S560: No), the ECU 100 determines that the inspection target system is abnormal (step S580).

  That is, when there is a change in the fuel level in the fuel trapper 500 (step S560: Yes), the ECU 100 determines the temperature of the fuel in the fuel tank 300 due to the exhaust heat of the engine 200 or the change in the outside air temperature. And the internal pressure of the tank rises, and it is determined that the system to be inspected is normal, assuming that the fuel is normally transferred between the fuel tank 300 and the fuel trapper 500 (step S570). If there is no change in the fuel liquid level in the fuel trapper 500 (step S560: No), the fuel liquid level in the fuel trapper 500 should originally change, but there is a hole or the like. Therefore, it is determined that the fuel is not transferred between the fuel tank 300 and the fuel trapper 500 (step S5). 0).

  Thus, according to this embodiment, since the liquid level sensor 540 is provided in the fuel trapper 500, the fuel level detected by the liquid level sensor 54 can be obtained without measuring the tank internal pressure. Based on this, it is possible to detect that an abnormality such as a hole has occurred in the inspection target system including the fuel tank 300.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist or concept of the invention that can be read from the claims and the entire specification. Is also included in the technical scope of the present invention.

  DESCRIPTION OF SYMBOLS 10 ... Vehicle, 100 ... ECU, 200 ... Engine, 300 ... Fuel tank, 345 ... Pressure sensor, 360 ... Evaporator line, 400 ... Canister, 450 ... Key-off pump, 500 ... Fuel trapper, 510 ... First communication passage, 520 ... First 2 communication passages, 530 ... open / close valve, 540 ... liquid level sensor, 600 ... motor generator

Claims (7)

A fuel tank for storing fuel;
A canister connected to the fuel tank via an evaporative fuel passage;
A fuel trapper provided separately from the fuel tank and capable of temporarily storing the fuel;
A first communication path communicating the lower part of the fuel tank and the lower part of the fuel trapper;
An evaporative fuel processing apparatus, comprising: a second communication path that communicates the upper space of the fuel trapper with the atmosphere.   The evaporated fuel treatment device according to claim 1, further comprising a block valve provided in the evaporated fuel passage and opened when a pressure in the fuel tank is equal to or higher than a predetermined valve opening pressure.   3. The evaporated fuel treatment device according to claim 1, wherein the fuel trapper is provided in a low temperature portion having a temperature lower than a portion in which the fuel tank is provided in a vehicle on which the evaporated fuel processing device is mounted.   4. The evaporated fuel treatment device according to claim 1, wherein the second communication path communicates with the atmosphere via the canister. 5.   5. The evaporation according to claim 4, further comprising an on-off valve provided in the second communication passage and configured to communicate the fuel trapper and the canister when the valve is opened and to block communication between the fuel trapper and the canister when the valve is closed. Fuel treatment device. Pressure detecting means for detecting the pressure in the fuel tank;
A first abnormality for determining whether or not an abnormality has occurred in the fuel tank based on the pressure detected by the pressure detection means in a state where communication between the fuel trapper and the canister is blocked by the on-off valve The evaporative fuel treatment device according to claim 5, further comprising: a determination unit. A liquid level detecting means for detecting a liquid level of the fuel in the fuel trapper;
8. The second abnormality determination means for determining whether or not an abnormality has occurred in the fuel tank based on the liquid level detected by the liquid level detection means. The evaporative fuel treatment apparatus as described in any one of Claims.

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