JP2010144531A - Evaporation fuel processing device and control method therefor - Google Patents

Abstract

An amount of evaporated fuel adsorbed on a canister can be reliably detected at any time, and versatility can be improved.
A fuel vapor processing apparatus includes a vapor passage, a canister, a purge passage, a drain passage, a sealing valve, a purge control valve, a pressure sensor, and an ECU. The ECU 24 detects the amount of evaporated fuel adsorbed by the canister 18 based on a pressure detection circuit 42 that detects the internal pressure of the canister 18 based on a signal from the pressure sensor 37 and a change in the internal pressure of the canister 18 when sealed. When it is determined that the canister 18 breaks based on the detected amount of evaporated fuel adsorbing circuit 44 and the detected amount of evaporated fuel, the engine is started and the purge control valve 40 is opened to perform purge. And a control circuit 46 that performs processing.
[Selection] Figure 1

Description

  The present invention includes a first communication path for introducing evaporated fuel generated in a fuel tank that stores fuel, a canister connected to the first communication path and adsorbing the evaporated fuel, and intake air of the canister and an internal combustion engine An evaporative fuel processing apparatus comprising: a second communication path that communicates with the path; and a purge processing unit that purges the evaporated fuel adsorbed by the canister to the internal combustion engine through the second communication path. About.

  A fuel tank is used to supply fuel to the internal combustion engine. In the fuel tank, vaporized fuel (vapor) is generated by vaporizing the fuel, and a canister is provided to prevent the vaporized fuel from unnecessarily diffusing into the atmosphere.

  The canister is filled with an adsorbent such as activated carbon and adsorbs and collects evaporated fuel. The collected evaporated fuel is purged through the purge passage into the intake passage of the internal combustion engine when the internal combustion engine is operated.

  By the way, after the fuel is supplied to the fuel tank, the operation of the internal combustion engine may be stopped for a long period of time. In particular, in a hybrid system that uses an internal combustion engine and a motor in combination, only traveling by the motor is performed, and the operation of the internal combustion engine may not be performed for a long period of time.

  At that time, a large amount of evaporated fuel is likely to be generated in the fuel tank, while the frequency of purging the evaporated fuel from the canister is extremely reduced. For this reason, evaporative fuel that cannot be collected by the canister may be released into the atmosphere.

  Therefore, for example, a control device for a generator driving engine disclosed in Patent Document 1 is known. This patent document 1 is mounted on an electric vehicle having an engine that receives supply of fuel from a fuel tank and a generator that generates power by being driven by the mechanical output of the engine, and at least a control device that controls the operation of the engine. Means for detecting the amount of fuel vapor in the fuel tank in a stopped state, means for starting the engine when the detected amount of vapor exceeds a first predetermined amount, and the engine is operating Means for detecting the amount of fuel vapor in the fuel tank in the state, and means for stopping the engine when the detected amount of vapor is equal to or less than a second predetermined amount. It is characterized by being smaller than one predetermined amount.

Japanese Patent Laid-Open No. 06-233410

  However, in Patent Document 1 described above, it is necessary to stop the engine when detecting the amount of fuel vapor in the fuel tank. For this reason, there is a problem that versatility is deteriorated because the fuel vapor amount cannot be detected and controlled except when the engine is stopped.

  The present invention solves this type of problem, and it is possible to reliably detect the amount of evaporated fuel adsorbed by a canister at any time, and to improve versatility, and its An object is to provide a control method.

  The present invention includes a first communication path for introducing evaporated fuel generated in a fuel tank that stores fuel, a canister connected to the first communication path and adsorbing the evaporated fuel, and intake air of the canister and an internal combustion engine The present invention relates to an evaporative fuel processing apparatus comprising: a second communication path that communicates with a passage; and a purge processing unit that purges the evaporated fuel adsorbed by the canister to the internal combustion engine through the second communication path. .

  The evaporative fuel processing apparatus is configured to determine the amount of evaporated fuel adsorbed to the canister based on a sealing mechanism that seals the canister, a pressure detection mechanism that detects an internal pressure of the canister, and a change in the internal pressure of the canister when sealed. An evaporative fuel adsorption amount detection mechanism that detects the evaporative fuel adsorption amount, and the purge processing unit performs the evaporative fuel purge process based on the detection result of the evaporative fuel adsorption amount detection mechanism.

  The evaporative fuel adsorption amount detection mechanism detects that the amount of evaporative fuel that can break through the canister is adsorbed by the canister when the internal pressure of the canister when sealed becomes a predetermined value or more. At the same time, the purge processing unit performs the evaporated fuel purge process when the evaporated fuel adsorption amount detection mechanism detects that the evaporated fuel is absorbed in the canister in an amount that the canister may break through. Preferably it is done.

  Further, the evaporative fuel adsorption amount detection mechanism has adsorbed to the canister an amount of evaporative fuel that may cause the canister to break through when the inclination of the internal pressure change of the canister when sealed becomes a predetermined inclination or more. When the evaporative fuel adsorption amount detecting mechanism detects that the evaporative fuel is absorbed in the canister, the purge processing unit detects that the evaporative fuel is adsorbed on the canister. A purge process is preferably performed.

  Furthermore, the evaporative fuel processing apparatus includes a depressurization mechanism that depressurizes the canister, a pressure detection mechanism that detects an internal pressure of the canister, and an evaporative fuel adsorbed on the canister based on an internal pressure gradient of the canister at the time of depressurization. An evaporative fuel adsorption amount detection mechanism for detecting the amount, and the purge processing unit performs the evaporative fuel purge process based on the detection result of the evaporative fuel adsorption amount detection mechanism.

  Further, the evaporative fuel adsorption amount detection mechanism is configured such that when the internal pressure gradient of the canister at the time of decompression becomes smaller than a predetermined gradient, an amount of evaporative fuel that is likely to break through the canister is adsorbed by the canister. When the evaporative fuel adsorption amount detection mechanism detects that the evaporative fuel is absorbed in the canister, the purge processing unit detects that the evaporative fuel adsorption amount detection mechanism detects that the evaporative fuel is adsorbed on the canister. It is preferable to perform a fuel purge process.

  Furthermore, the evaporative fuel processing apparatus includes a depressurization mechanism that depressurizes the canister, a pressure detection mechanism that detects an internal pressure of the canister, and an evaporative fuel adsorbed on the canister based on an internal pressure gradient of the canister after depressurization. An evaporative fuel adsorption amount detection mechanism for detecting the amount, and the purge processing unit performs the evaporative fuel purge process based on the detection result of the evaporative fuel adsorption amount detection mechanism.

  Further, the evaporative fuel adsorption amount detection mechanism is configured such that when the internal pressure gradient of the canister after depressurization becomes larger than a predetermined gradient, an amount of evaporative fuel that may cause the canister to break through is adsorbed by the canister. When the evaporative fuel adsorption amount detection mechanism detects that the evaporative fuel is absorbed in the canister, the purge processing unit detects that the evaporative fuel adsorption amount detection mechanism detects that the evaporative fuel is adsorbed on the canister. It is preferable to perform a fuel purge process.

  Further, the evaporative fuel processing apparatus includes: a depressurization mechanism that depressurizes the canister; a temperature detection mechanism that detects the temperature of the canister; and an amount of evaporative fuel adsorbed to the canister based on a temperature gradient of the canister at the time of depressurization The purge processing unit performs a purge process of the evaporated fuel based on the detection result of the evaporated fuel adsorption amount detection mechanism.

  Furthermore, the evaporative fuel adsorption amount detection mechanism is configured such that when the temperature gradient of the canister during decompression becomes larger than a predetermined gradient, the evaporative fuel in an amount that the canister may break through is adsorbed by the canister. And when the evaporative fuel adsorption amount detection mechanism detects that the evaporative fuel in an amount that the canister may break through is adsorbed to the canister, It is preferable to perform an evaporative fuel purge process.

  Further, the evaporative fuel processing device calculates a time until the canister breaks through when the evaporative fuel is not purged from the canister to the internal combustion engine based on the evaporative fuel amount detected by the evaporative fuel adsorption amount detection mechanism. It is preferable that a purge time calculating mechanism is provided, and the purge processing unit performs the purge process of the evaporated fuel based on the calculated time.

  Furthermore, the present invention provides a first communication path for introducing evaporated fuel generated in a fuel tank for storing fuel, a canister connected to the first communication path and adsorbing the evaporated fuel, the canister and an internal combustion engine Of the evaporative fuel processing apparatus, comprising: a second communication path that communicates with the intake path of the engine; and a purge processing section that purges the evaporated fuel adsorbed by the canister to the internal combustion engine through the second communication path. It is about the method.

  The control method includes a step of detecting an internal pressure of the canister while the canister is sealed, a step of detecting an amount of evaporated fuel adsorbed on the canister based on a change in the internal pressure of the canister when sealed, And a step of purging the evaporated fuel based on the detected amount of the evaporated fuel.

  Furthermore, when the internal pressure of the canister at the time of sealing becomes a predetermined value or more, a step of detecting that the amount of evaporated fuel that can break through the canister is adsorbed by the canister, and the canister breaks down. And a step of purging the evaporated fuel when it is detected that an amount of the evaporated fuel having a possibility of passing is adsorbed to the canister.

  A step of detecting when the canister is adsorbed by the canister when an amount of evaporative fuel that is likely to break through the canister when an inclination of the internal pressure change of the canister when sealed becomes equal to or greater than a predetermined inclination; It is preferable to have a step of purging the evaporated fuel when it is detected that an amount of the evaporated fuel having a possibility of breaking through is adsorbed to the canister.

  Further, the control method includes a step of depressurizing the canister, a step of detecting an internal pressure of the canister, a step of detecting an amount of evaporated fuel adsorbed on the canister based on an internal pressure gradient of the canister at the time of depressurization, And a step of purging the evaporated fuel based on the detected amount of the evaporated fuel.

  A step of detecting when the canister is adsorbed by the canister when an internal pressure gradient of the canister at the time of depressurization is smaller than a predetermined gradient; It is preferable to have a step of purging the evaporated fuel when it is detected that an amount of the evaporated fuel having a possibility of breaking through the canister is adsorbed by the canister.

  Further, the control method includes a step of depressurizing the canister, a step of detecting the internal pressure of the canister, and a step of detecting the amount of evaporated fuel adsorbed on the canister based on the internal pressure gradient of the canister after depressurization. And a step of purging the evaporated fuel based on the detected amount of the evaporated fuel.

  Furthermore, when the internal pressure gradient of the canister after depressurization becomes a gradient larger than a predetermined gradient, a step of detecting that the amount of evaporated fuel that can break through the canister is adsorbed by the canister; It is preferable to have a step of purging the evaporated fuel when it is detected that an amount of the evaporated fuel having a possibility of breaking through the canister is adsorbed by the canister.

  Further, the control method includes a step of depressurizing the canister, a step of detecting the temperature of the canister, a step of detecting the amount of evaporated fuel adsorbed on the canister based on a temperature gradient of the canister at the time of depressurization, And a step of purging the evaporated fuel based on the detected amount of the evaporated fuel.

  Furthermore, when the temperature gradient of the canister at the time of decompression becomes a gradient larger than a predetermined gradient, the step of detecting that the amount of evaporated fuel that can break through the canister is adsorbed by the canister; It is preferable to have a step of purging the evaporated fuel when it is detected that an amount of the evaporated fuel having a possibility of breaking through the canister is adsorbed by the canister.

  Furthermore, the control method calculates a time until the canister breaks through when the evaporated fuel is not purged from the canister to the internal combustion engine based on the detected amount of evaporated fuel, and the calculated And a step of purging the fuel vapor based on time.

  In the present invention, the canister is sealed or depressurized, the amount of evaporated fuel adsorbed on the canister is detected based on the internal pressure change, the internal pressure gradient or the temperature gradient of the canister, and based on the detected amount of the evaporated fuel. Thus, the evaporative fuel purge process is performed. Therefore, regardless of the state of the internal combustion engine, that is, whether the engine is operating or stopped, the amount of evaporated fuel adsorbed by the canister can be reliably detected at any time, and the versatility can be improved. .

  FIG. 1 is a schematic configuration diagram of a fuel tank system 10 to which an evaporative fuel processing apparatus according to a first embodiment of the present invention is applied. The fuel tank system 10 is mounted on a vehicle (not shown), and is particularly preferably used in a hybrid system using both an engine (not shown) and a motor (not shown).

  The fuel tank system 10 is connected to the fuel tank 12 for storing the fuel F, the vapor passage (first communication passage) 16 for introducing the evaporated fuel (vapor) in the fuel tank 12 from the float 14, and the vapor passage 16. The canister 18 that adsorbs the evaporated fuel, the drain passage 20 that communicates the canister 18 with the outside air and introduces external air into the canister 18 when the evaporated fuel is purged, and the canister 18 A purge passage (second communication passage) 22 for sucking (purging) the evaporated fuel into an intake passage communicating with the engine (not shown) when the engine is driven, and an ECU (electronic control unit) 24 are provided.

  One end of an oil supply pipe member 26 is attached to the fuel tank 12. A cap 28 is attached to the other end portion of the oil supply pipe member 26, and a breather pipe 30 is provided from the vicinity of the cap 28 toward the space S of the fuel tank 12.

  In the fuel tank 12, a fuel pump 32 for supplying the fuel F stored in the fuel tank 12 to the engine, and a fuel supply amount detection unit for detecting the fuel supply amount of the fuel F supplied to the fuel tank 12. (For example, float) 34 is arranged.

  The canister 18 is filled with an adsorbent (not shown) such as activated carbon. A sealing valve 36 and a pressure sensor 37 are disposed in the vapor passage 16. The drain passage 20 and the purge passage 22 are provided with a sealing valve 38 and a purge control valve 40, respectively. The sealing valves 36 and 38 constitute a sealing mechanism that seals the canister 18, while the purge control valve 40 constitutes a purge processing unit that purges the evaporated fuel adsorbed by the canister 18 into the internal combustion engine.

  The ECU 24 detects the internal pressure of the canister 18 based on a signal from the pressure sensor 37, and the evaporation adsorbed by the canister 18 based on the change in the internal pressure of the canister 18 when sealed. An evaporative fuel adsorption amount detection circuit (evaporative fuel adsorption amount detection mechanism) 44 for detecting the amount of fuel, and the canister 18 breakthrough based on the evaporative fuel amount detected by the evaporative fuel adsorption amount detection circuit 44. When it is determined, a control circuit 46 is provided that starts the engine and opens the purge control valve 40 to perform the purge process.

  FIG. 2 shows the relationship between the internal pressure P of the canister 18 and the elapsed time when sealed. The evaporative fuel adsorption amount detection circuit 44 uses, for example, the internal pressure P1 of the canister 18 as a threshold, and detects an evaporative fuel adsorption amount having a possibility of breakthrough when an internal pressure P0 that is equal to or higher than the internal pressure P1 is detected It is determined that the canister 18 breaks through. This is because the internal pressure of the canister 18 and the evaporated fuel adsorption amount have a certain relationship.

  The vapor passage 16, the canister 18, the purge passage 22, the drain passage 20, the sealing valves 36 and 38, the purge control valve 40, the pressure sensor 37, and the ECU 24 constitute the evaporated fuel processing device 50 according to the first embodiment.

  The operation of the fuel tank system 10 configured as described above will be described below along the flowchart shown in FIG. 3 in relation to the control method according to the first embodiment.

  First, as shown in FIG. 1, the sealing valves 36 and 38 are closed, and the purge control valve 40 is closed, whereby the canister 18 is sealed (step S1). In this state, the pressure detection circuit 42 detects a change in the internal pressure of the canister 18 based on a detection signal from the pressure sensor 37 (step S2).

  As shown in FIG. 2, the evaporated fuel adsorption amount detection circuit 44 detects whether or not the detected internal pressure P of the canister 18 is equal to or higher than a threshold value P1, thereby evaporating the canister 18 with a possibility of breakthrough. It is determined whether or not there is a fuel adsorption amount. When it is determined that the detected internal pressure P of the canister 18 is the internal pressure P0 that is equal to or higher than the threshold value P1 (YES in step S3), the process proceeds to step S4, and a purge process is performed.

  In this purge process, the control circuit 46 starts an engine (not shown) and opens the purge control valve 40. Therefore, the fuel F stored in the fuel tank 12 is supplied to the engine via the fuel pump 32. On the other hand, when air is supplied to the engine, a negative pressure is generated in an intake passage (not shown), and the evaporated fuel collected in the canister 18 is purged under the opening of the purge control valve 40. It is sucked into the passage 22 and purged.

  At that time, when the sealing valve 38 is opened, outside air flows from the drain passage 20 into the canister 18. Accordingly, the evaporated fuel adsorbed in the canister 18 is purged into the intake passage together with the inflowing outside air.

  In step S3, if it is determined that the detected internal pressure P of the canister 18 is the internal pressure P2 that is less than the threshold value P1, that is, the canister 18 has no possibility of breakthrough (NO in step S3). ), And the process is terminated without performing the purge process.

  In this case, in the first embodiment, a change in the internal pressure of the canister 18 is detected in a state where the canister 18 is sealed, and the amount of evaporated fuel adsorbed on the canister 18 is determined based on the change in the internal pressure. Then, it is determined whether or not the evaporated fuel adsorbing amount passes through.

  Therefore, regardless of the state of the engine, that is, whether the engine is operating or stopped, the amount of evaporated fuel adsorbed by the canister 18 can be detected reliably and accurately at any time, and the versatility can be improved. The effect that it becomes possible is obtained.

  In addition, before the canister 18 breaks through, the engine can be started to purge the evaporated fuel in the canister 18. Thus, particularly in the hybrid system, there is an advantage that breakthrough from the canister 18 can be surely prevented when the engine is stopped for a long period of time.

  A control method according to the second embodiment of the present invention will be described below with reference to FIGS. 4 and 5. In the first embodiment, the fuel tank system 10 shown in FIG. 1 is used.

  FIG. 4 shows the relationship between the pressure gradient of the canister 18 and the elapsed time. The evaporative fuel adsorption amount detection circuit 44 detects whether or not the inclination of the detected internal pressure of the canister 18 is larger than a predetermined inclination R0, whereby the evaporative fuel adsorption amount having a possibility of breakthrough is detected in the canister 18. Determine if it exists. When the amount of adsorption of the canister 18 is large, a large inclination R01 is obtained. On the other hand, when the amount of adsorption of the canister 18 is small, a small inclination R02 is obtained.

  In the second embodiment, as shown in FIG. 5, after the canister 18 is sealed (step S1a), a change in the internal pressure of the canister 18 is detected (step S2a). As shown in FIG. 4, the evaporated fuel adsorption amount detection circuit 44 breaks through the canister 18 by detecting whether or not the detected inclination of the internal pressure of the canister 18 is larger than a predetermined inclination R0 that is a threshold value. It is determined whether or not there is an evaporated fuel adsorption amount having the possibility of When it is determined that the detected inclination of the internal pressure of the canister 18 is an inclination R01 that is larger than the predetermined inclination R0 (YES in step S3a), the process proceeds to step S4a and a purge process is performed.

  Thus, in the second embodiment, the inclination of the internal pressure of the canister 18 is detected, and based on the inclination of the internal pressure, the amount of evaporated fuel adsorbed on the canister 18 is the evaporated fuel adsorption amount that breaks through. Judging whether there is. As a result, the second embodiment can obtain the same effect as the first embodiment, and can determine the possibility of breakthrough in a relatively short time without having to wait until the internal pressure becomes stable. There is an advantage of becoming.

  FIG. 6 is a schematic configuration diagram of a fuel tank system 60 to which the evaporated fuel processing apparatus according to the third embodiment of the present invention is applied. Note that the same components as those in the fuel tank system 10 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. Similarly, in the fourth and subsequent embodiments described below, detailed description thereof is omitted.

  The fuel tank system 60 includes a pressure reducing mechanism, for example, a pump 62, disposed in the drain passage 20 and depressurizing the canister 18. The evaporated fuel adsorption amount detection circuit 44 detects the amount of evaporated fuel adsorbed to the canister 18 based on the internal pressure gradient of the canister 18 when the canister 18 is depressurized under the action of the pump 62.

  FIG. 7 shows the relationship between the pressure gradient (change in pressure) of the internal pressure P of the canister 18 during pressure reduction and the elapsed time. The evaporative fuel adsorption amount detection circuit 44 determines, for example, that the canister 18 breaks through when the gradient R1 having an inclination smaller than the internal pressure gradient R is detected with the internal pressure gradient R of the canister 18 as a threshold value.

  The vapor passage 16, the canister 18, the purge passage 22, the drain passage 20, the sealing valves 36 and 38, the purge control valve 40, the pressure sensor 37, the pump 62, and the ECU 24 include the evaporated fuel processing device 64 according to the third embodiment. Constitute.

  The operation of the fuel tank system 60 configured as described above will be described below along the flowchart shown in FIG. 8 in relation to the control method according to the third embodiment. In addition, the detailed description is abbreviate | omitted about the process similar to the control method which concerns on 1st Embodiment shown in FIG.

  In the third embodiment, after the sealing valve 36 and the purge control valve 40 are closed, the pump 62 is driven to decompress the canister 18 (step S11). At that time, the pressure detection circuit 42 detects a change in the internal pressure of the canister 18 based on a signal from the pressure sensor 37 (step S12).

  As shown in FIG. 7, the evaporated fuel adsorption amount detection circuit 44 detects whether or not the detected internal pressure gradient of the canister 18 is smaller than the internal pressure gradient R, thereby causing the canister 18 to break through. It is determined whether or not the evaporated fuel adsorption amount exists. When the adsorption amount of the canister 18 is large, an internal pressure gradient R1 having a small inclination is obtained. On the other hand, when the adsorption amount of the canister 18 is small, an internal pressure gradient R2 having a large inclination is obtained. This is because if the amount of adsorption is large, a large amount of fuel is released when the canister 18 is depressurized, and a decrease in internal pressure of the canister 18 is suppressed.

  Then, when it is determined that the detected internal pressure gradient of the canister 18 is smaller than the internal pressure gradient R (YES in step S13), the process proceeds to step S14, and a purge process is performed.

  Thus, in the third embodiment, a change in the internal pressure gradient of the canister 18 is detected in a state where the canister 18 is decompressed, and the evaporated fuel adsorbed on the canister 18 based on the change in the internal pressure gradient. It is determined whether or not the amount is the amount of evaporated fuel adsorbed through. Thereby, the third embodiment can obtain the same effects as those of the first and second embodiments.

  A control method according to the fourth embodiment of the present invention will be described below with reference to FIGS. 9 and 10. In the fourth embodiment, a fuel tank system 60 shown in FIG. 6 is used.

  FIG. 9 shows the relationship between the pressure gradient of the canister 18 and the elapsed time in a state where the pressure is maintained after the canister 18 is depressurized. The evaporative fuel adsorption amount detection circuit 44 determines that the canister 18 breaks through, for example, when an internal pressure gradient L of the canister 18 is used as a threshold and a gradient L1 having a larger gradient than the internal pressure gradient L is detected. In FIG. 9, the internal pressure gradient L0 indicates an internal pressure pattern when the canister 18 is depressurized and no evaporated fuel is present in the canister 18. The internal pressure gradient L0 maintains a state in which a reduced pressure is maintained, that is, a state in which the internal pressure does not change.

  In the fourth embodiment, after the pressure in the canister 18 is reduced (step S21 in FIG. 10), the pressure in the canister 18 is maintained (step S22). While the pressure is being held, the pressure detection circuit 42 detects a change in the internal pressure of the canister 18 based on a signal from the pressure sensor 37 (step S23).

  As shown in FIG. 9, the evaporated fuel adsorption amount detection circuit 44 detects whether or not the internal pressure gradient of the canister 18 detected after depressurization is larger than the internal pressure gradient L, thereby giving the canister 18 a possibility of breakthrough. It is determined whether or not there is an evaporated fuel adsorption amount. When the amount of adsorption of the canister 18 is large, a pressure gradient L1 having a large inclination is obtained. On the other hand, when the amount of adsorption of the canister 18 is small, a pressure gradient L2 having a small inclination is obtained.

  When it is determined that the detected internal pressure gradient of the canister 18 is larger than the internal pressure gradient L (YES in step S24), the process proceeds to step S25, and a purge process is performed.

  As described above, in the fourth embodiment, after the canister 18 is depressurized, a change in the internal pressure gradient of the canister 18 is detected in a state where the pressure is maintained. Based on the change in the internal pressure gradient, It is determined whether or not the amount of evaporated fuel adsorbed on the canister 18 is the amount of evaporated fuel adsorbed to break through. Thereby, the effect similar to the 1st-3rd embodiment is acquired.

  FIG. 11 is a schematic configuration diagram of a fuel tank system 70 to which the evaporated fuel processing apparatus according to the fifth embodiment of the present invention is applied.

  The fuel tank system 70 is driven and controlled via an ECU (electronic control unit) 72. The ECU 72 includes a temperature detection circuit (temperature detection mechanism) 74 that detects the temperature of the canister 18. The canister 18 is provided with a plurality of temperature sensors 76. Each temperature sensor 76 detects a temperature change for each area in the canister 18, and the detected temperature information is sent to the temperature detection circuit 74.

  FIG. 12 shows the relationship between the temperature gradient (temperature change) of the canister 18 and the elapsed time during decompression. The evaporative fuel adsorption amount detection circuit 44 determines that the canister 18 breaks through, for example, when the temperature gradient T1 having a larger gradient than the temperature gradient T is detected using the temperature gradient T of the canister 18 as a threshold value.

  The vapor passage 16, the canister 18, the purge passage 22, the drain passage 20, the sealing valves 36 and 38, the purge control valve 40, the temperature sensor 76, and the ECU 72 constitute an evaporated fuel processing device 78 according to the fifth embodiment.

  The operation of the fuel tank system 70 configured as described above will be described below along the flowchart shown in FIG. 13 in relation to the control method according to the fifth embodiment.

  In the fifth embodiment, the inside of the canister 18 is depressurized (step S31), and the temperature detection circuit 74 detects a temperature change for each area in the canister 18 via a plurality of temperature sensors 76 (step S31). S32).

  As shown in FIG. 12, the evaporated fuel adsorption amount detection circuit 44 detects whether or not the detected temperature gradient of the canister 18 is larger than the temperature gradient T, thereby causing the canister 18 to break through. It is determined whether or not the evaporated fuel amount exists. When the adsorption amount of the canister 18 is large, a temperature gradient T1 having a large inclination is obtained. On the other hand, when the adsorption amount of the canister 18 is small, a temperature gradient T2 having a small inclination is obtained. This is because when the evaporated fuel is released from the activated carbon in the canister 18, endotherm is induced.

  When it is determined that the detected temperature gradient of the canister 18 is greater than the temperature gradient T (YES in step S33), the process proceeds to step S34, and a purge process is performed.

  Thus, in the fifth embodiment, a change in the temperature gradient of the canister 18 is detected in a state where the canister 18 is decompressed, and the evaporated fuel adsorbed on the canister 18 based on the change in the temperature gradient. It is determined whether or not the amount is the amount of evaporated fuel adsorbed through. Thereby, the fifth embodiment can obtain the same effects as those of the first to fourth embodiments.

  FIG. 14 is a schematic configuration diagram of a fuel tank system 80 to which the evaporated fuel processing apparatus according to the sixth embodiment of the present invention is applied. In addition, although 6th Embodiment uses 1st Embodiment substantially, it is not limited to this, You may employ | adopt in any of 2nd-5th Embodiment.

  The fuel tank system 80 is driven and controlled via an ECU (electronic control unit) 82. Based on the amount of evaporated fuel detected by the evaporated fuel adsorption amount detection circuit 44, the ECU 82 calculates a time until the canister 18 breaks through when the evaporated fuel is not purged from the canister 18 to the engine. A calculation circuit (breakthrough time calculation mechanism) 84 is provided. The ECU 82 is provided with a timer 86 as a time measuring means.

  For example, as shown in FIG. 15, the evaporated fuel adsorption amount detection circuit 44 has a relationship between the canister internal pressure and the adsorption amount at the time of sealing as a map or as a calculation formula. For example, as shown in FIG. 16, the evaporated fuel adsorption amount detection circuit 44 has a relationship between the adsorption amount and the breakthrough time of the canister 18 as a map or as a calculation formula.

  The vapor passage 16, the canister 18, the purge passage 22, the drain passage 20, the sealing valves 36 and 38, the purge control valve 40, the pressure sensor 37, and the ECU 82 constitute an evaporated fuel processing device 88 according to the sixth embodiment.

  The operation of the fuel tank system 80 configured as described above will be described below along the flowchart shown in FIG. 17 in relation to the control method according to the sixth embodiment.

  First, the canister 18 is closed (step S41), and the internal pressure of the canister 18 is detected (step S42). As shown in FIG. 15, the evaporated fuel adsorption amount detection circuit 44 detects the adsorption amount of the evaporated fuel adsorbed by the canister 18 from the detected internal pressure of the canister 18 (step S43).

  Next, when it is determined that there is a possibility of breakthrough in the canister 18 based on the detected amount of adsorption (YES in step S44), the process proceeds to step S45, and the time until the canister 18 breaks through. The breakthrough time is calculated (see FIG. 16). When the breakthrough time calculated by the timer 86 × k (where k ≦ 1) is counted (YES in step S46), the control circuit 46 proceeds to step S47 and performs a purge process.

  As described above, in the sixth embodiment, the canister 18 that has adsorbed the evaporated fuel starts the engine and purges the evaporated fuel in the canister 18 before breaking through as time elapses. it can. Thereby, especially in a hybrid system, when the engine is stopped for a long period of time, it is possible to reliably prevent breakthrough from the canister 18.

  In addition, the adsorption state of the canister 18 can be detected with high accuracy. For this reason, it becomes possible to suppress the operating time of the engine to the minimum necessary, and there is an advantage that it is economical by reducing fuel consumption.

1 is a schematic configuration diagram of a fuel tank system to which an evaporated fuel processing apparatus according to a first embodiment of the present invention is applied. FIG. 4 is a relationship diagram between elapsed time and canister internal pressure. It is a flowchart explaining the control method which concerns on 1st Embodiment. In the control method which concerns on 2nd Embodiment, it is a related figure of the elapsed time and the inclination of canister internal pressure. It is a flowchart explaining the control method which concerns on 2nd Embodiment. It is a schematic block diagram of the fuel tank system with which the evaporative fuel processing apparatus which concerns on the 3rd Embodiment of this invention is applied. FIG. 4 is a relationship diagram between elapsed time and canister internal pressure. It is a flowchart explaining the control method which concerns on 3rd Embodiment. In the control method which concerns on 4th Embodiment, it is a related figure of elapsed time and canister internal pressure. It is a flowchart explaining the control method which concerns on 4th Embodiment. It is a schematic block diagram of the fuel tank system with which the evaporative fuel processing apparatus which concerns on the 5th Embodiment of this invention is applied. It is a related figure of elapsed time and canister temperature. It is a flowchart explaining the control method which concerns on 5th Embodiment. It is a schematic block diagram of the fuel tank system with which the evaporative fuel processing apparatus which concerns on the 6th Embodiment of this invention is applied. It is a relationship diagram between canister internal pressure and adsorption amount. It is a related figure of adsorption amount and breakthrough time. It is a flowchart explaining the control method which concerns on 6th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Fuel tank system 12 ... Fuel tank 16 ... Vapor passage 18 ... Canister 20 ... Drain passage 22 ... Purge passage 24, 72, 82 ... ECU26 ... Refueling pipe member 32 ... Fuel pump 34 ... Refueling amount detection part 36, 38 ... Seal valve 37 ... Pressure sensor 40 ... Purge control valve 42 ... Pressure detection circuit 44 ... Evaporated fuel adsorption amount detection circuit 46 ... Control circuit 50, 64, 78, 88 ... Evaporated fuel processing devices 60, 70, 80 ... Fuel tank system 62 ... Pump 74 ... Temperature detection circuit 76 ... Temperature sensor 84 ... Breakthrough time calculation circuit 86 ... Timer

Claims (20)

A first communication path for introducing evaporated fuel generated in a fuel tank for storing fuel;
A canister connected to the first communication path and adsorbing the evaporated fuel;
A second communication passage communicating the canister and the intake passage of the internal combustion engine;
A purge processing unit for purging the evaporated fuel adsorbed by the canister to the internal combustion engine through the second communication path;
An evaporative fuel processing apparatus comprising:
A sealing mechanism for sealing the canister;
A pressure detection mechanism for detecting the internal pressure of the canister;
An evaporative fuel adsorption amount detection mechanism for detecting the amount of the evaporative fuel adsorbed to the canister based on a change in the internal pressure of the canister during sealing;
With
The evaporative fuel processing apparatus, wherein the purge processing unit performs the evaporative fuel purge process based on a detection result of the evaporative fuel adsorption amount detection mechanism. 2. The fuel vapor treatment apparatus according to claim 1, wherein the fuel vapor adsorption amount detection mechanism is configured to cause the canister to break through when the internal pressure of the canister when sealed becomes a predetermined value or more. Detecting that fuel is adsorbed to the canister,
The purge processing unit performs the evaporated fuel purge process when the evaporated fuel adsorption amount detection mechanism detects that the evaporated fuel is absorbed in the canister in an amount that the canister may break through. An evaporative fuel processing apparatus characterized by performing. 2. The fuel vapor treatment apparatus according to claim 1, wherein the fuel vapor adsorption amount detection mechanism has a possibility that the canister may break through when a slope of a change in internal pressure of the canister when sealed becomes a predetermined slope or more. And detecting that the evaporated fuel is adsorbed to the canister,
The purge processing unit performs the evaporated fuel purge process when the evaporated fuel adsorption amount detection mechanism detects that the evaporated fuel is absorbed in the canister in an amount that the canister may break through. An evaporative fuel processing apparatus characterized by performing. A first communication path for introducing evaporated fuel generated in a fuel tank for storing fuel;
A canister connected to the first communication path and adsorbing the evaporated fuel;
A second communication passage communicating the canister and the intake passage of the internal combustion engine;
A purge processing unit for purging the evaporated fuel adsorbed by the canister to the internal combustion engine through the second communication path;
An evaporative fuel processing apparatus comprising:
A decompression mechanism for decompressing the canister;
A pressure detection mechanism for detecting the internal pressure of the canister;
An evaporative fuel adsorption amount detection mechanism for detecting an amount of the evaporative fuel adsorbed to the canister based on an internal pressure gradient of the canister during decompression;
With
The evaporative fuel processing apparatus, wherein the purge processing unit performs the evaporative fuel purge process based on a detection result of the evaporative fuel adsorption amount detection mechanism. 5. The fuel vapor treatment apparatus according to claim 4, wherein the fuel vapor adsorption amount detection mechanism has a possibility that the canister breaks through when an internal pressure gradient of the canister during decompression becomes smaller than a predetermined gradient. Detecting that an amount of the evaporated fuel is adsorbed to the canister;
The purge processing unit performs the evaporated fuel purge process when the evaporated fuel adsorption amount detection mechanism detects that the evaporated fuel is absorbed in the canister in an amount that the canister may break through. An evaporative fuel processing apparatus characterized by performing. A first communication path for introducing evaporated fuel generated in a fuel tank for storing fuel;
A canister connected to the first communication path and adsorbing the evaporated fuel;
A second communication passage communicating the canister and the intake passage of the internal combustion engine;
A purge processing unit for purging the evaporated fuel adsorbed by the canister to the internal combustion engine through the second communication path;
An evaporative fuel processing apparatus comprising:
A decompression mechanism for decompressing the canister;
A pressure detection mechanism for detecting the internal pressure of the canister;
An evaporative fuel adsorption amount detection mechanism for detecting the amount of the evaporative fuel adsorbed to the canister based on the internal pressure gradient of the canister after depressurization;
With
The evaporative fuel processing apparatus, wherein the purge processing unit performs the evaporative fuel purge process based on a detection result of the evaporative fuel adsorption amount detection mechanism. 7. The fuel vapor treatment apparatus according to claim 6, wherein the fuel vapor adsorption amount detection mechanism has a possibility that the canister breaks through when the internal pressure gradient of the canister after depressurization becomes larger than a predetermined gradient. Detecting that an amount of the evaporated fuel is adsorbed to the canister;
The purge processing unit performs the evaporated fuel purge process when the evaporated fuel adsorption amount detection mechanism detects that the evaporated fuel is absorbed in the canister in an amount that the canister may break through. An evaporative fuel processing apparatus characterized by performing. A first communication path for introducing evaporated fuel generated in a fuel tank for storing fuel;
A canister connected to the first communication path and adsorbing the evaporated fuel;
A second communication passage communicating the canister and the intake passage of the internal combustion engine;
A purge processing unit for purging the evaporated fuel adsorbed by the canister to the internal combustion engine through the second communication path;
An evaporative fuel processing apparatus comprising:
A decompression mechanism for decompressing the canister;
A temperature detection mechanism for detecting the temperature of the canister;
An evaporative fuel adsorption amount detection mechanism for detecting the amount of the evaporative fuel adsorbed to the canister based on a temperature gradient of the canister during decompression;
With
The evaporative fuel processing apparatus, wherein the purge processing unit performs the evaporative fuel purge process based on a detection result of the evaporative fuel adsorption amount detection mechanism. 9. The fuel vapor treatment apparatus according to claim 8, wherein the fuel vapor adsorption amount detection mechanism has a possibility that the canister breaks through when a temperature gradient of the canister during decompression becomes larger than a predetermined gradient. Detecting that an amount of the evaporated fuel is adsorbed to the canister;
The purge processing unit performs the evaporated fuel purge process when the evaporated fuel adsorption amount detection mechanism detects that the evaporated fuel is absorbed in the canister in an amount that the canister may break through. An evaporative fuel processing apparatus characterized by performing. The evaporated fuel processing apparatus according to claim 1, wherein the evaporated fuel is supplied from the canister to the internal combustion engine based on the amount of the evaporated fuel detected by the evaporated fuel adsorption amount detection mechanism. Provided with a breakthrough time calculation mechanism for calculating the time until the canister breakthrough when not purged
The purge processing unit performs the vaporized fuel purge process based on the calculated time. A first communication path for introducing evaporated fuel generated in a fuel tank for storing fuel;
A canister connected to the first communication path and adsorbing the evaporated fuel;
A second communication passage communicating the canister and the intake passage of the internal combustion engine;
A purge processing unit for purging the evaporated fuel adsorbed by the canister to the internal combustion engine through the second communication path;
A method for controlling an evaporative fuel processing apparatus comprising:
Detecting the internal pressure of the canister with the canister sealed; and
Detecting the amount of the evaporated fuel adsorbed on the canister based on a change in the internal pressure of the canister during sealing;
A step of purging the evaporated fuel based on the detected amount of the evaporated fuel;
A control method for an evaporative fuel processing apparatus, comprising: 12. The control method according to claim 11, wherein when the internal pressure of the canister at the time of sealing becomes a predetermined value or more, it is detected that the amount of the evaporated fuel that can break through the canister is adsorbed by the canister. And a process of
Performing a purge process of the evaporated fuel when it is detected that an amount of the evaporated fuel having a possibility of breakthrough of the canister is adsorbed by the canister;
A control method for an evaporative fuel processing apparatus, comprising: 12. The control method according to claim 11, wherein when the inclination of the internal pressure change of the canister when sealed becomes equal to or greater than a predetermined inclination, an amount of the vaporized fuel that can break through the canister is adsorbed by the canister. Detecting the presence of
Performing a purge process of the evaporated fuel when it is detected that an amount of the evaporated fuel having a possibility of breakthrough of the canister is adsorbed by the canister;
A control method for an evaporative fuel processing apparatus, comprising: A first communication path for introducing evaporated fuel generated in a fuel tank for storing fuel;
A canister connected to the first communication path and adsorbing the evaporated fuel;
A second communication passage communicating the canister and the intake passage of the internal combustion engine;
A purge processing unit for purging the evaporated fuel adsorbed by the canister to the internal combustion engine through the second communication path;
A method for controlling an evaporative fuel processing apparatus comprising:
Depressurizing the canister;
Detecting the internal pressure of the canister;
Detecting an amount of the evaporated fuel adsorbed on the canister based on an internal pressure gradient of the canister during decompression;
A step of purging the evaporated fuel based on the detected amount of the evaporated fuel;
A control method for an evaporative fuel processing apparatus, comprising: 15. The control method according to claim 14, wherein when the internal pressure gradient of the canister during decompression becomes smaller than a predetermined gradient, an amount of the vaporized fuel that may cause the canister to break through is adsorbed by the canister. A step of detecting when
Performing a purge process of the evaporated fuel when it is detected that an amount of the evaporated fuel having a possibility of breakthrough of the canister is adsorbed by the canister;
A control method for an evaporative fuel processing apparatus, comprising: A first communication path for introducing evaporated fuel generated in a fuel tank for storing fuel;
A canister connected to the first communication path and adsorbing the evaporated fuel;
A second communication passage communicating the canister and the intake passage of the internal combustion engine;
A purge processing unit for purging the evaporated fuel adsorbed by the canister to the internal combustion engine through the second communication path;
A method for controlling an evaporative fuel processing apparatus comprising:
Depressurizing the canister;
Detecting the internal pressure of the canister;
Detecting the amount of the evaporated fuel adsorbed on the canister based on the internal pressure gradient of the canister after depressurization;
A step of purging the evaporated fuel based on the detected amount of the evaporated fuel;
A control method for an evaporative fuel processing apparatus, comprising: 17. The control method according to claim 16, wherein when the internal pressure gradient of the canister after depressurization becomes a gradient larger than a predetermined gradient, an amount of the evaporated fuel that can break through the canister is adsorbed by the canister. A step of detecting when
Performing a purge process of the evaporated fuel when it is detected that an amount of the evaporated fuel having a possibility of breakthrough of the canister is adsorbed by the canister;
A control method for an evaporative fuel processing apparatus, comprising: A first communication path for introducing evaporated fuel generated in a fuel tank for storing fuel;
A canister connected to the first communication path and adsorbing the evaporated fuel;
A second communication passage communicating the canister and the intake passage of the internal combustion engine;
A purge processing unit for purging the evaporated fuel adsorbed by the canister to the internal combustion engine through the second communication path;
A method for controlling an evaporative fuel processing apparatus comprising:
Depressurizing the canister;
Detecting the temperature of the canister;
Detecting the amount of the evaporated fuel adsorbed on the canister based on a temperature gradient of the canister during decompression;
A step of purging the evaporated fuel based on the detected amount of the evaporated fuel;
A control method for an evaporative fuel processing apparatus, comprising: 19. The control method according to claim 18, wherein when the temperature gradient of the canister during decompression becomes larger than a predetermined gradient, an amount of the evaporated fuel that can break through the canister is adsorbed by the canister. A step of detecting when
Performing a purge process of the evaporated fuel when it is detected that an amount of the evaporated fuel having a possibility of breakthrough of the canister is adsorbed by the canister;
A control method for an evaporative fuel processing apparatus, comprising: The control method according to any one of claims 11 to 19, wherein the canister breaks through when the evaporated fuel is not purged from the canister to the internal combustion engine based on the detected amount of the evaporated fuel. Calculating the time until
A step of purging the fuel vapor based on the calculated time;
A control method for an evaporative fuel processing apparatus, comprising:

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