Device for treating evaporated fuel

Abstract

Device (1; 1a) for treating vaporized fuel, comprising: a vapor channel (16) connected to a fuel tank (FT); a container (11) for storing vaporized fuel supplied from the fuel tank (FT) through the vapor channel (16); an atmosphere channel (15) connecting the container (11) to an open-to-atmosphere port (18); a full-tank control valve (30) located at the end of the vapor channel (16) on one side of the fuel tank (FT); a pressure sensor (21) for detecting the internal pressure of the fuel tank (FT); a fuel volume measuring unit (20) for measuring the fuel volume in the fuel tank (FT); and an operating unit (28; 26) to be actuated for carrying out fuel filling, wherein the device (1; 1a) for treating vaporized fuel further comprises: an electrically operated valve (32; 32a),which is located between the control valve (30) for full tank filling and the connection (18) open to the atmosphere; and a control unit (17) for controlling the electrically operated valve (32; 32a), wherein the control unit (17) is configured to perform a control to close the electrically operated valve (32, 32a) in order to completely close the electrically operated valve (32; 32a) when a condition for closing the electrically operated valve (32, 32a) after the start of fuel filling is met, namely that a value measured by the fuel volume measuring unit (20) is equal to or greater than a first predetermined value that has been pre-determined, and a value detected by the pressure sensor (21) is equal to or greater than a second predetermined value that has been pre-determined, characterized in that the control unit (17) also, when the valve closing condition is met,The control unit (17) deactivates the control for closing the electrically operated valve (32, 32a) when the condition for closing the electrically operated valve (32, 32a) is met a number of times less than a predetermined number (n) of times, and the control unit (17) performs the control for closing the electrically operated valve (32, 32a) when the number of times the condition for closing the electrically operated valve (32, 32a) is met reaches the predetermined number (n) of times.

Description

TECHNICAL AREA The present disclosure relates to a device for treating vaporized fuel, with which vaporized fuel is treated that is produced in a fuel tank of an internal combustion engine installed in a vehicle. BACKGROUND TECHNIQUES A device for treating evaporated fuel is used to prevent the release of evaporated fuel generated in a fuel tank into the atmosphere. In this device, the fuel evaporated in the fuel tank is placed in a container holding an adsorbent and temporarily adsorbed onto it. Whenever a purging condition is met, depending on the operating state of the internal combustion engine, a purge is performed to flush the evaporated fuel, now adsorbed onto the adsorbent, through a purge channel into the intake manifold of the internal combustion engine. Some such devices for handling evaporated fuel have a mechanical full-tank control valve located at the lower end of a vapor channel (an end located in the fuel tank) (see Patent Document 1). This full-tank control valve is configured to open when the fuel level in the fuel tank falls below the full-tank liquid level. As the fuel level rises to the full-tank liquid level, a float in the full-tank control valve moves upward, closing the valve. Once the full-tank control valve is closed, the internal pressure of the fuel tank consequently increases, and the fuel is drawn up to the vicinity of a fuel filler neck (tank filler neck) of a fuel filler pipe.This activates an automatic stop function of the fuel nozzle to interrupt the fuel filling through the nozzle and consequently prevent fuel from overflowing from the fuel filler pipe. In the generic patent specification 2, a fuel tank system is proposed. It comprises a fuel tank with a fuel filling opening, a vapor channel connecting the fuel tank to a storage tank, a shut-off valve provided in the vapor channel with an adjustable valve opening degree, a device for sensing the fuel level in the fuel tank, and a control device for controlling the valve opening degree of the shut-off valve. The control device is configured to change the valve opening degree of the shut-off valve to a predetermined value when the fuel level detected by the fuel level sensing device during the refueling process reaches a predetermined upper limit, and then closes the shut-off valve to a fully closed position.The shut-off valve opening is maintained at a predetermined value even if the fuel level reaches a predefined upper limit during refueling. The fuel tank system also includes an internal tank pressure sensing device for monitoring the pressure inside the fuel tank. Based on the detected internal tank pressure, the control device closes the shut-off valve to a fully closed position once the valve opening has been maintained at a predetermined value. This prevents the shut-off valve from closing before the internal fuel tank pressure has stabilized and precisely suppresses the recoil of evaporated fuel. Patent document 3 describes methods and systems for refilling a fuel tank that avoid fuel vapors. Patent document 4 describes a method for removing vapors during a refueling process on board. Patent document 5 describes a method for controlling a filling process of a liquid storage system for vehicles, comprising a tank with a filling pipe and a shut-off valve. PRINTED FONT ON RELATED TECHNIQUES PATENT PRINTING FONT Patent Publication 1: JP 2011-178379A Patent Publication 2: JP 2019-85875A Patent Publication 3: DE 10 2019 123 924 A1 Patent Publication 4: US 2009 / 0 078 239 A1 Patent Publication 5: US 2016 / 0 060 093 A1 SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION However, in the vaporizing fuel treatment device described above in Patent Document 1, the full-tank control valve opens after a certain period of time (10 seconds to several tens of seconds) has elapsed since the full-tank control valve closed, causing the fuel level in the fuel filler pipe to drop and allowing further fuel filling. As a result, a user who wants to fill the fuel tank to its full capacity will have to perform two or more additional fill-ups. This can lead to overfilling. If additional fuel is added beyond the tank's capacity, it can flow into the vapor channel and penetrate further into the container, potentially damaging it. Such a situation must be avoided. The present disclosure was made to address the problems described above and aims to provide a device for treating evaporated fuel that is capable of reliably preventing additional fuel filling that exceeds the capacity of a fuel tank. MEANS TO SOLVENT THE PROBLEMS To achieve the above-stated objective, the invention provides a device for treating vaporized fuel, comprising: a vapor channel connected to a fuel tank; a container for storing vaporized fuel supplied from the fuel tank through the vapor channel; an atmosphere channel connecting the container to a port open to the atmosphere; a full-tank control valve located at the end of the vapor channel on one side of the fuel tank; a pressure sensor for detecting the internal pressure of the fuel tank; and a fuel volume measuring unit for measuring the fuel volume in the fuel tank.and an operating unit to be actuated for carrying out fuel filling, characterized in that the device for treating evaporated fuel further comprises: an electrically operated valve located between the control valve for full tank filling and the connection open to atmosphere; and a control unit for controlling the electrically operated valve, wherein the control unit is configured to perform a control to close the valve in order to completely close the electrically operated valve when a condition for closing the valve after the start of fuel filling is met, namely that a value measured by the fuel volume measuring unit is equal to or greater than a first predetermined value that has been predetermined, and a value detected by the pressure sensor is equal to or greater than a second predetermined value that has been predetermined. In the aforementioned device for handling vaporized fuel, the electrically operated valve is located between the full-tank control valve and the connection to the open atmosphere, i.e., in the vapor channel or the atmosphere channel. After fuel filling begins, the control unit initiates the valve closure when the valve closing condition is met. Specifically, as soon as the value measured by the fuel volume measuring unit becomes equal to or greater than the predetermined value, the electrically operated valve closes completely. This occurs when the pressure in the fuel tank increases and the value detected by the pressure sensor reaches or exceeds the second predetermined value.In this system, the electrically operated valve is not fully closed until the value measured by the fuel volume measuring unit reaches the first predetermined value. Therefore, the electrically operated valve is not yet fully closed even if an initial interruption occurs and the internal pressure of the fuel tank rises sharply early in the refueling process. If the amount of fuel supplied subsequently increases and the full-tank control valve is closed, the fuel level in the filler neck rises, and consequently, the fuel delivery via the nozzle is interrupted by an automatic stop function. At this point, the internal pressure of the fuel tank temporarily rises above the second predetermined value, causing the electrically operated valve to close. Accordingly, the fuel level in the filler neck is maintained, while further fuel delivery is prevented. This prevents overfilling. The control unit can include, for example, a cap switch, a cap flap, or other devices. In the aforementioned device for treating evaporated fuel, the control unit deactivates the control to close the valve even when the valve closing condition is met, namely when the valve closing condition is met a number of times that is less than a predetermined number of times, and the control unit then carries out the control to close the valve when the number of times the valve closing condition is met reaches the predetermined number of times. This design allows the number of times additional refueling is permitted (the allowed number of additional refuelings), thus enabling fuel to be added up to a full fuel tank capacity while reliably preventing overfilling. The allowed number of additional refuelings can be set to an optimal number for each vehicle type, depending on the amount of fuel added at which the full-tank control valve closes and the capacity of the fuel filler neck. In the aforementioned device for treating evaporated fuel, the control unit can open the electrically operated valve while the valve is still closed before fuel is supplied, when the control unit detects that the operating unit is being actuated. When the electrically operated valve is closed in a sealed fuel tank system, refueling is impossible. Therefore, if the electrically operated valve is closed before refueling, the control unit opens it as soon as it detects that the operating unit has been activated (for example, when a cap switch is pressed), i.e., when refueling is about to begin. This ensures smooth refueling and reliably prevents overfilling beyond the tank's capacity. Furthermore, a vehicle equipped with a sealed fuel tank system already has this electrically operated valve and can thus achieve the effect described above without the addition of any new components. In the aforementioned device for treating evaporated fuel, it is further preferred that, if the electrically operated valve is in an open state before fuel filling and then the electrically operated valve is closed after the end of fuel filling, the control unit opens the electrically operated valve when the control unit detects that a cover flap has been closed. This design reliably prevents further refueling that exceeds the fuel tank's capacity and allows the container to properly handle the evaporated fuel after refueling is complete. If it is detected that the lid flap is closed after refueling is complete, but the permitted number of additional refueling attempts have not been made, the electrically operated valve will remain open. In the aforementioned device for treating evaporated fuel, it is preferred that the control unit, before the electrically operated valve is closed, performs a temporary control to close the valve in order to set a valve opening degree of the electrically operated valve of 10% to 50% if the value measured by the fuel volume measuring unit is equal to or greater than a third predetermined value which is less than the first predetermined value, and the value detected by the pressure sensor is less than the second predetermined value. With this setup, before the full-tank control valve closes, the valve closure is temporarily controlled to adjust the opening of the electrically operated valve from 10% to 50%. Therefore, when the full-tank control valve is triggered to close, the electrically operated valve can reliably close completely without any delay. This setup thus even more reliably prevents overfilling beyond the fuel tank's capacity. EFFECTS OF THE INVENTION According to the present disclosure, a device for treating evaporated fuel can be provided which is able to prevent additional fuel refueling that exceeds the capacity of a fuel tank. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic diagram showing the general structure of an engine system comprising a device for treating vaporized fuel according to a first embodiment; Fig. 2 is a flowchart showing a control system during fuel filling according to the first embodiment; Fig. 3 is a diagram showing the state of the fuel in a fuel tank and fuel line during an initial phase of fuel filling; Fig. 4 is a diagram showing the state of the fuel in the fuel tank and fuel line at a first automatic interruption; Fig. 5 is a diagram showing the state of the fuel in the fuel tank and fuel line once a full-tank control valve opens after the first automatic interruption; Fig.Figure 6 is a diagram showing the state of the fuel in the fuel tank and fuel line during a second automatic interruption; Figure 7 is a diagram showing the state of the fuel in the fuel tank and fuel line once a valve closing condition of an electrically operated valve is met, and consequently the electrically operated valve is closed; Figure 8 is a diagram showing changes in the fuel level, the internal tank pressure, and the opening degree of the electrically operated valve during the control operation during fuel filling; Figure 9 is a schematic diagram showing a general setup of an engine system that includes a device for treating vaporized fuel according to a second embodiment; and Figure 10 is a flowchart showing a control operation during fuel filling according to the second embodiment. METHODS FOR IMPLEMENTING THE INVENTION (First embodiment) A detailed description of a device for treating evaporated fuel, which is an embodiment of the present disclosure, is provided below with reference to the accompanying drawings. The first embodiment describes an example in which a device for treating evaporated fuel is applied to the engine system of a vehicle using a sealed tank system. <General structure of the system> The engine system, in which a device 1 for treating vaporized fuel is implemented, is mounted on a vehicle such as an automobile. In this device 1, as shown in Fig. 1, an engine ENG is connected to an intake manifold IP for supplying air (intake air) to the engine ENG. A throttle THR (a throttle valve) is provided in the intake manifold IP to open and close the intake manifold IP and thereby control the amount of air flowing into the engine ENG (the amount of intake air). Upstream of the throttle THR, i.e., on one side upstream with respect to the direction of intake air flow, an air cleaner AC is provided in the intake manifold IP to remove contaminants from the air flowing in the intake manifold IP. Consequently, air passes through the air cleaner AC in the intake manifold IP and is drawn into the engine ENG. The device 1 for treating vaporized fuel according to this embodiment is configured to supply the vaporized fuel produced in the fuel tank FT to the engine ENG through the intake manifold IP in such an engine system, so that the vaporized fuel is treated in the engine ENG. The device 1 for treating vaporized fuel comprises a fuel tank FT, a container 11, a purge channel 12, a purge control valve 14, an atmosphere channel 15, a vapor channel 16, a control unit 17, and a connection 18 open to the atmosphere, as well as further components. The fuel tank FT is configured to store fuel to be supplied to the engine ENG. The fuel tank FT is equipped internally with a fuel pump FP to supply the fuel in the fuel tank FT to the engine ENG through a fuel line (not shown). The fuel tank FT is equipped with a liquid level sensor 20 for detecting the fuel level in order to measure the volume of fuel stored in the fuel tank FT (a residual amount of fuel), and with a pressure sensor 21 for detecting the pressure of an upper space above the fuel level, i.e., the internal tank pressure. The liquid level sensor 20 is an example of a "fuel volume measuring unit" according to the present invention. The fuel tank FT described above is connected to a fuel line 25 for pumping (supplying) fuel into the tank. The fuel filler pipe 25 is provided at its upper end with a fuel filler connection 25a, to which a removable tank cap 25b is attached. A cover flap 26 is provided outside the tank cap 25b and attached to the fuel filler connection 25a to cover the tank cap 25b and the fuel filler connection 25a. A cover opening and closing sensor 27 is provided near this cover flap 26 to detect the open / closed state of the cover flap 26. Container 11 contains an adsorbent such as activated carbon to collect (adsorb and retain) the vaporized fuel produced in fuel tank FT. This container 11 is connected to fuel tank FT via vapor channel 16 and temporarily stores the vaporized fuel flowing into it from fuel tank FT through vapor channel 16. Container 11 is also connected to purge channel 12 and atmosphere channel 15. The purge channel 12 is connected to the intake tract IP and the reservoir 11. Accordingly, purge gas (containing the vaporized fuel) flows from the reservoir 11 through the purge channel 12 and is fed to the intake tract IP. In the example shown in Fig. 1, the purge channel 12 is connected to the intake tract IP at a position downstream with respect to the throttle THR, i.e., on one side downstream with respect to the flow direction of the intake air relative to the throttle THR. The purge control valve 14 is located in the purge channel 12. The purge control valve 14 opens and closes the purge channel 12. When the purge control valve 14 is closed (in a closed state), the purge gas in the purge channel 12 is shut off by the purge control valve 14 and does not flow into the intake tract IP. Conversely, when the purge control valve 14 is open (in an open state), the purge gas flows into the intake tract IP. The atmosphere channel 15 has one end open to the atmosphere as a port 18, while the other end is connected to the container 11 to connect the container 11 to the atmosphere. This atmosphere channel 15 allows the air drawn in through the open port 18 to flow. Furthermore, a filter 19 is positioned near the open port 18. The vapor channel 16 is connected to the fuel tank FT and the container 11. Accordingly, the vaporized fuel in the fuel tank FT flows through the vapor channel 16 into the container 11. A full-tank control valve 30 is provided at the lower end of the vapor channel 16, i.e., at the end located in the fuel tank FT. The full-tank control valve 30 has a simple design, opening when the fuel level in the fuel tank FT is lower than the upper limit (the fuel level when the tank is full), and simply having a float to close when the fuel level rises to the upper limit. The full-tank control valve 30 serves to prevent fuel from entering the vapor channel 16. In this embodiment, an electrically operated valve 32 is placed in the vapor channel 16. This electrically operated valve 32 is opened and closed by the control unit 17. Specifically, the valve 32 is closed when it is not supplied with power, thus blocking the connection between the fuel tank FT and the container 11. Conversely, the valve 32 is open when it is supplied with power, thus enabling a connection between the fuel tank FT and the container 11. The device 1 for treating vaporized fuel according to the present embodiment assumes a sealed tank system and therefore does not need to add the electrically operated valve 32. The control unit 17 is part of a vehicle-mounted ECU (not shown) and is integrally configured with the other part of the ECU (for example, a part that controls the engine ENG). The control unit 17 can also be configured separately from the other part of the ECU. The control unit 17 has memory, such as a CPU, ROM, and RAM. The control unit 17 controls the vaporized fuel treatment device 1 and the engine system according to pre-stored programs in the memory. For example, the control unit 17 controls the purge control valve 14, the fuel pump FP, and others. Furthermore, the control unit 17 receives output signals from the fluid level sensor 20, the pressure sensor 21, the cap opening and closing sensor 27, the cap switch 28, and others. In the present embodiment, the lid switch 28 is connected to the control unit 17. The lid switch 28 is, for example, located inside a vehicle and is operated by a user to open the lid flap 26 for refueling. When operated by a user, the lid switch 28 sends a signal to the control unit 17. This lid switch 28 is an example of an operating unit according to the present invention. In the device 1 for treating vaporized fuel, as described above, the control unit 17 opens the purge control valve 14 to perform the purge control when the purge condition is met during engine operation ENG. The purge control is a control for introducing purge gas from the reservoir 11 into the intake tract IP through the purge channel 12. During the purge control operation, the engine ENG is supplied with air drawn into the intake manifold IP, fuel supplied from the fuel tank FT and injected by an injector, and purge gas supplied to the intake manifold IP by the purge control system. The control unit 17 adjusts the injection timing of the injector and the valve opening time of the purge control valve 14 to set the air-fuel ratio (A / F) of the engine ENG to an optimal air-fuel ratio, for example, an ideal air-fuel ratio. <details der steuerung während kraftstoffbefüllung> Next, with reference to Figures 2, 3, 4, 5, 6, 7 to 8, the control operation during fuel refueling is described, which is carried out by the device 1 for treating evaporated fuel during the refueling of a vehicle. In this embodiment, the control unit 17 performs the control operation during fuel refueling based on a control sequence shown in Figure 2. In particular, the control unit 17 first determines whether the lid switch 28 has been switched to the "open" position (step S1). If the lid switch 28 is "open" (S1: Yes), the control unit 17 opens the electrically operated valve 32 (step S2). As a result, the fuel evaporated in the fuel tank FT is introduced into the container 11 and recovered there.The gas component without the vaporized fuel is released into the atmosphere via the atmosphere channel 15 and the connection 18 open to the atmosphere. When the tank internal pressure detected by the pressure sensor 21 is close to atmospheric pressure (step S3: Yes), the control unit 17 opens the lid flap 26 (step S4). Fuel filling then begins. As shown particularly in Fig. 3, the tank cap 25b is removed from the fuel filler neck 25a, and a dispensing nozzle 40 is inserted into the fuel filler neck 25a. The fuel flowing from the dispensing nozzle 40 is then fed to the fuel tank FT through the fuel filler tube 25. As refueling progresses, the amount of fuel supplied to fuel tank FT gradually increases, and the fuel level in fuel tank FT gradually rises. As shown in Fig. 4, the full-tank control valve 30 closes when the fuel level reaches the full-tank level. The internal pressure of fuel tank FT then increases, and fuel is drawn up to the vicinity of the fuel filler port 25a of the fuel filler pipe 25. This activates an automatic stop function of the dispensing nozzle 40 to interrupt fuel delivery from the nozzle 40 (initial automatic interruption). During this refilling process, the control unit 17 determines whether a first valve closing condition (a liquid level condition) for the electrically operated valve 32 is met. Specifically, the control unit 17 determines whether a value detected by the liquid level sensor 20 is equal to or greater than a predetermined value H1 (e.g., 80% of the liquid level of a full tank) or not (step S5). If the value detected by the liquid level sensor 20 is equal to or greater than the predetermined value H1 (S5: Yes), the control unit 17 further determines whether a second valve closing condition (a pressure condition) for the electrically operated valve 32 is met. Specifically, the control unit 17 determines whether the number of times the internal pressure of the fuel tank FT exceeds a predetermined value P1 (e.g., 3 kPa) reaches the set number n (step S6)., the control unit 17 determines whether the number of times the valve closing condition of the electrically operated valve 32 is met (i.e., both the first valve closing condition and the second valve closing condition are met) reaches the set number n of times or not. The set number n of times (n being a natural number) is determined based on the permitted number of additional refueling operations specified for the respective vehicle type. For example, if the amount of fuel added is 98% of the fuel tank capacity at the first automatic interruption, and the amount of fuel added per additional refueling operation is 1% of the fuel tank capacity, then the set number n of times can be n=3. That is, assuming a permitted number of times is x, the set number n of times is n=x+1. Because the set number n of times is determined in the manner described above, the electrically operated valve 32 will close (i.e., be fully closed) on the xth (=n-1) additional refueling operation after the first automatic interruption., if the valve closing condition of the electrically operated valve 32 has been met n times, and therefore the fuel can be supplied up to the capacity of the fuel tank of 100%. If the number of times the tank pressure increases is less than n (S6: No), then the control unit 17 determines, based on a signal from the lid opening and closing sensor 27, whether the lid flap 26 is closed or not (step S7). If the lid flap 26 is closed (S7: Yes), then the control unit 17 closes (i.e., closes completely) the electrically operated valve 32 (step S8). For example, this condition corresponds to a situation where the specified number n of times is n=3, and an additional fuel filling operation is only permitted up to 2 times, in which the additional fuel filling is carried out only once, after which the fuel filling stops and the lid flap 26 is closed. If, on the other hand, the lid flap 26 is not closed (S7: No), it is assumed that an additional fuel filling operation should continue.In the same case as described above, for example, it is assumed that the second fuel filling process is to be carried out. If an additional fuel filling operation is to be carried out, the full-tank control valve 30 is reopened approximately 10 seconds after it was closed, as shown in Fig. 5. In this case, the internal pressure of the fuel tank FT decreases, and the fuel level in the fuel filler tube 25 drops, thus enabling the additional fuel filling operation. Once the additional fuel filling operation is performed, the full-tank control valve 30 is closed again, as shown in Fig. 6, and fuel is once again pumped to the vicinity of the fuel filler port 25a of the fuel filler tube 25. As a result, the automatic stop function of the dispensing nozzle 40 is activated to interrupt the fuel delivery from the nozzle 40 (second automatic interruption).This results in a second increase in the tank's internal pressure. The processes of steps S7 and S8 are then repeated. When the number of times the internal pressure of the fuel tank FT increases reaches the predetermined number n (S6: Yes), the control unit 17 closes (i.e., completely closes) the electrically operated valve 32 as shown in Fig. 7 (S8). This condition corresponds, for example, to a situation where the predetermined number n is n=3, and the additional fuel filling has been carried out twice. As a result, the internal pressure of the fuel tank FT does not decrease, so the fuel level in the fuel filler tube 25 does not drop. Thus, additional fuel filling is prevented. In other words, additional fuel filling more often than the predetermined number (n-1) is reliably prevented.According to the device 1 for treating evaporated fuel of the present embodiment, the permissible number of additional fuel refueling operations can be determined as described above. This device 1 therefore allows fuel refueling up to the full capacity of the fuel tank FT (100% of the fuel tank capacity), while reliably preventing additional fuel refueling that exceeds the capacity of the fuel tank FT. Because the control is based on the control sequence shown in Fig. 2, the fuel level and internal pressure of the fuel tank FT, as well as the degree of opening of the electrically operated valve 32, vary as shown in Fig. 8, for example, when the number n of times is n=3. Specifically, if fuel filling is started at time T1, the internal pressure of the fuel tank FT increases slightly, and the fuel level gradually rises. At time T2, the fuel level reaches the predetermined value H1, thus fulfilling the first valve closing condition (the liquid level condition) for the electrically operated valve 32. Therefore, at a subsequent time T3, the first automatic interruption occurs.In this case, the tank's internal pressure exceeds the predetermined value P1, and consequently, the second valve closing condition (the pressure condition) for the electrically operated valve 32 is fulfilled. However, the number of times the tank's internal pressure increases is only one, which is less than the predetermined number n of times (n=3), thus allowing for an additional fuel filling operation. When the first additional fuel filling process is carried out, the second automatic interruption occurs at time T4. During this interruption, the tank pressure repeatedly exceeds the predetermined value P1, thus fulfilling the second valve closing condition (the pressure condition) for the electrically operated valve 32. However, the number of times the tank pressure increases is only two, which is less than the predetermined number n of times (n=3), so the next (second) additional fuel filling process is carried out. When the second additional fuel filling process is carried out, the third automatic interruption occurs at time T5. Here, the tank's internal pressure again exceeds the predetermined value P1, thus fulfilling the second valve closing condition (the pressure condition) for the electrically operated valve 32. Consequently, the number of times the tank's internal pressure increases is now three, thus reaching the predetermined number n of times (n=3). Accordingly, once the tank has been filled to its full capacity of 100%, further fuel filling is no longer possible, and the fuel filling process is complete. Subsequently, the electrically operated valve 32 closes (fully closes), and the fuel level in the fuel filler pipe 25 no longer decreases.This can reliably prevent additional refueling that exceeds the capacity of the fuel tank FT. If, for example, the temperature in the fuel tank FT is elevated in summer, the refilled fuel evaporates immediately. As a result, an initial interruption can occur, during which the internal pressure of the fuel tank FT rises sharply in an initial phase of the fuel filling process (time t1), as shown by the dashed line in Fig. 8. When such an initial interruption occurs, the second valve closing condition (the pressure condition) of the electrically operated valve 32 is met, while at time t1 the first valve closing condition (the liquid level condition) for the electrically operated valve 32 is not met. In the present embodiment, the electrically operated valve 32 is therefore not closed, even if an initial interruption occurs. Furthermore, before closing (fully closing) the electrically operated valve 32, the control unit 17 can perform a temporary valve closing control to set the valve opening degree of the electrically operated valve 32 to 10 to 50% (for example, 40%) at time t2, when the tank internal pressure is lower than the predetermined value P1, and the fuel level reaches a predetermined value H2 (H2 < H1) or higher (see dashed line of the valve opening degree). The electrically operated valve 32 can be actuated by a stepper motor. In the temporary valve closing control performed as described above, the valve opening degree of the electrically operated valve 32 can be reduced in advance before the control valve 30 closes for full tank filling. When the control valve 30 is closed accordingly, the electrically operated valve 32 can be fully closed safely without any delay in response. This makes it possible to prevent additional fuel filling that exceeds the capacity of the fuel tank FT even more reliably. According to the device 1 for treating evaporated fuel described above in the present embodiment, the liquid level in the fuel filler tube 25 rises as the amount of fuel being filled increases and the control valve 30 is then closed for a full tank. After this, the fuel filling from the nozzle 40 is interrupted by the automatic stop function of the nozzle 40. When the number of times the value detected by the liquid level sensor 20 is equal to or greater than the predetermined value H1, and when, in addition, the internal pressure of the fuel tank FT temporarily rises above the predetermined value P1, reaches the predetermined number n, the electrically operated valve 32 is closed. Accordingly, the fuel level in the fuel filler tube 25 is maintained, and consequently, further additional fuel filling is prevented.This design can prevent additional fuel refueling that exceeds the capacity of the fuel tank FT. The permitted number (n-1) of times for additional fuel refueling can be determined as described above, making it possible to fill the fuel tank FT to its full capacity while reliably preventing any further additional fuel refueling that exceeds the capacity of the fuel tank FT. (Second example) A second embodiment is described below. In the second embodiment, the device for treating evaporated fuel, which is provided with a general fuel tank FT that does not correspond to a sealed tank system, is described with reference to Figures 9 and 10. As shown in Figure 9, a device 1a for treating evaporated fuel of the second embodiment is essentially identical to that of the first embodiment, except that no lid switch 28 is provided and an electrically operated valve 32a is a normally open valve.In particular, in the device 1a for the treatment of evaporated fuel of this embodiment, the electrically operated valve 32a is open when it is not supplied with power, which allows a connection between the fuel tank FT and the container 11, and is closed when it is supplied with power, thereby blocking the connection between the fuel tank FT and the container 11. <details der steuerung während kraftstoffbefüllung> Next, the control performed by the device 1a for treating evaporated fuel during refueling is described in the case of refueling a vehicle with reference to Fig. 10. In this embodiment, the control unit 17 performs the control during refueling based on the control sequence shown in Fig. 10. In particular, the control unit 17 determines whether the cover flap 26 is open or not (step S11). If the cover flap 26 is open (S11: Yes) and refueling has begun, the control unit 17 determines whether the first valve closing condition (the liquid level condition) for the electrically operated valve 32a is met or not. More precisely, the control unit 17 determines whether the value detected by the liquid level sensor 20 is equal to or greater than the predetermined value H1 (step S12).The electrically operated valve 32a is in an open state. If the value detected by the liquid level sensor 20 is equal to or greater than the predetermined value H1 (S 12: yes), the control unit 17 further determines whether the second valve closing condition (the pressure condition) of the electrically operated valve 32a is met or not. In particular, the control unit 17 determines whether the number of times the internal pressure of the fuel tank FT exceeds the predetermined value P1 reaches the predetermined number n or not (step S13). That is, the control unit 17 determines whether the number of times the valve closing condition for the electrically operated valve 32a is met (i.e., both the first valve closing condition and the second valve closing condition are met) reaches the predetermined number n or not. If the number of times the tank internal pressure increases is less than n (S13: No), the control unit 17 determines, based on a signal from the lid opening and closing sensor 27, whether the lid flap 26 is closed or not (step S14). If the lid flap 26 is closed (S14: Yes), the control unit 17 determines that the fuel filling has ended and terminates this processing routine. This condition corresponds, for example, to a situation where, if the specified number n of times is n=3, with up to two additional fuel fillings allowed, the additional fuel filling is actually carried out only once, and then the fuel filling is stopped and the lid flap 26 is closed. In this case, the fuel volume in the fuel tank FT is not 100%, and consequently, the electrically operated valve 32a remains open.The evaporated fuel can therefore be treated appropriately by container 11. If, on the other hand, the cover flap 26 has not been closed (S14: No), it is assumed that an additional fuel filling is to be carried out. For example, in the case mentioned above (n=3), it is assumed that the second additional fuel filling is to be carried out. Consequently, the actions in steps S13 and S14 are repeated. If the number of times the internal pressure of the fuel tank FT increases reaches the predetermined number n (S13: Yes), the control unit 17 closes (i.e., completely closes) the electrically operated valve 32a (step S15). This condition corresponds, for example, to a situation in a case where the predetermined number n is n=3, in which the additional fuel filling has been carried out twice. As a result, the internal pressure of the fuel tank FT does not decrease, so the fuel level in the fuel filler tube 25 does not drop.Consequently, further additional refueling is prevented. In other words, an additional refueling exceeding the predetermined number of times (n-1) is reliably prevented. After the electrically operated valve 32a has closed, the control unit 17 determines, when the cover flap 26 is closed, that the fuel filling has ended and then opens the electrically operated valve 32a (step S17). Consequently, the evaporated fuel can be appropriately treated after the fuel filling has ended in the container 11. With the device 1a for treating evaporated fuel in the present embodiment, configured as described above, the permissible number of additional fuel fillings can also be determined. This setup allows the fuel tank FT to be filled to its full capacity (100%), while reliably preventing any additional fuel filling that exceeds the capacity of the fuel tank FT. According to the device 1a for treating evaporated fuel in the present embodiment, the liquid level in the fuel filler tube 25 rises as described above when the amount of fuel supplied increases and the control valve 30 is closed for a full tank, after which the fuel supply from the nozzle 40 is interrupted by the automatic function of the nozzle 40. When the number of times the value detected by the liquid level sensor 20 is equal to or greater than the predetermined value H1, and furthermore the internal pressure of the fuel tank FT temporarily exceeds the predetermined value P1, reaches the predetermined number n, the electrically operated valve 32a is closed. As a result, the liquid level in the fuel filler tube 25 is maintained, thus preventing further additional fuel filling.This design can prevent additional refueling that exceeds the capacity of the fuel tank FT. The permitted number (n-1) of times for additional refueling can be determined as described above, making it possible to fill the fuel tank FT to its full capacity while reliably preventing additional refueling that exceeds the capacity of the fuel tank FT. The preceding embodiments are merely examples and do not constitute a limitation of the present disclosure. The present disclosure can also be implemented in other ways without deviating from its essential features. For example, in the preceding embodiment, the electrically operated valve 32 (32a) is placed in the vapor channel 16. Alternatively, the electrically operated valve 32 (32a) can also be placed in the atmosphere channel 15. In the preceding embodiments, the device for treating vaporized fuel according to the present disclosure is applied to naturally aspirated engine systems, but the device for treating vaporized fuel according to the present disclosure can, of course, also be applied to turbocharged engine systems. REFERENCE MARK LIST 1 Evaporated fuel treatment device 1a Evaporated fuel treatment device 11 Container 15 Atmosphere channel 16 Vapor channel 17 Control unit 20 Liquid level sensor 21 Pressure sensor 25 Fuel filler pipe 26 Lid flap 27 Lid opening and closing sensor 28 Lid switch 30 Full tank control valve 32 Electrically operated valve 32a Electrically operated valve ENG Engine FT Fuel tank< / details> < / details>

Claims

Device (1; 1a) for treating vaporized fuel, comprising: a vapor channel (16) connected to a fuel tank (FT); a container (11) for storing vaporized fuel supplied from the fuel tank (FT) through the vapor channel (16); an atmosphere channel (15) connecting the container (11) to an open-to-atmosphere port (18); a full-tank control valve (30) located at the end of the vapor channel (16) on one side of the fuel tank (FT); a pressure sensor (21) for detecting the internal pressure of the fuel tank (FT); a fuel volume measuring unit (20) for measuring the fuel volume in the fuel tank (FT); and an operating unit (28; 26) to be actuated for carrying out fuel filling, wherein the device (1; 1a) for treating vaporized fuel further comprises: an electrically operated valve (32; 32a),which is located between the control valve (30) for full tank filling and the connection (18) open to the atmosphere; and a control unit (17) for controlling the electrically operated valve (32; 32a), wherein the control unit (17) is configured to perform a control to close the electrically operated valve (32, 32a) in order to completely close the electrically operated valve (32; 32a) when a condition for closing the electrically operated valve (32, 32a) after the start of fuel filling is met, namely that a value measured by the fuel volume measuring unit (20) is equal to or greater than a first predetermined value that has been pre-determined, and a value detected by the pressure sensor (21) is equal to or greater than a second predetermined value that has been pre-determined, characterized in that the control unit (17) also, when the valve closing condition is met,The control unit (17) deactivates the control for closing the electrically operated valve (32, 32a) when the condition for closing the electrically operated valve (32, 32a) is met a number of times less than a predetermined number (n) of times, and the control unit (17) performs the control for closing the electrically operated valve (32, 32a) when the number of times the condition for closing the electrically operated valve (32, 32a) is met reaches the predetermined number (n) of times. Device (1) for treating evaporated fuel according to claim 1, wherein, while the electrically operated valve (32) is still closed before filling with fuel, the control unit (17) opens the electrically operated valve (32) when the control unit (17) detects that the operating unit (28) is being actuated. Device (1a) for treating evaporated fuel according to claim 1, wherein, if the electrically operated valve (32a) is in an open state before fuel filling and then the electrically operated valve (32a) is closed after the end of fuel filling, the control unit (17) opens the electrically operated valve (32a) when the control unit (17) detects that a cover flap (26) has been closed. Device (1; 1a) for treating evaporated fuel according to one of claims 1 to 3, wherein the control unit (17), before the electrically operated valve (32; 32a) is closed, when the value measured by the fuel volume measuring unit (20) is equal to or greater than a third predetermined value which is less than the first predetermined value, and the value detected by the pressure sensor (20) is less than the second predetermined value, performs a temporary control to close the electrically operated valve (32, 32a) in order to set a valve opening degree of the electrically operated valve (32; 32a) from 10% to 50%.

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