Refueling equipment

Abstract

To provide a fueling device capable of maintaining an outlet pressure of a VR pump at a specified value.SOLUTION: A fueling device (100) includes a VR line (1) communicated from a fueling nozzle (6) to a fuel storage tank (5) for returning a vapor generated during fueling to the fuel storage tank (5). A VR pump (2) is interposed in the VR line (1) for sucking, pressurizing, and discharging the vapor. A back pressure adjustment valve (3) having a function for maintaining the pressure on a discharge port side of the VR pump (2) at a set value is interposed in a discharge side region of the VR pump (2) of the VR line (1).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a refueling device, and more particularly to a technique for preventing vapor generated during refueling from leaking out of the refueling device. [Background technology]

[0002] For example, when a highly volatile fuel such as gasoline is filled into a fuel tank of an automobile, a large amount of vapor is generated in the fuel tank. If such vapor is released into the atmosphere, it may cause a fire risk and may become a cause of environmental pollution. Therefore, a technology has been proposed for collecting the vapor in the fuel tank through a fuel filling nozzle (see Patent Document 1 and Patent Document 2). Also, a vapor recovery system (VR system) has been proposed that recovers vapor in the fuel supply device (fuel storage tank). In such a VR system, the amount of fuel dispensed and the amount of vapor recovered should be equal to prevent vapor from being released into the atmosphere during refueling. This is because if the amount of fuel dispensed is too much, vapor will be released into the atmosphere from the fuel filler of the vehicle tank, and if the amount of vapor recovered is too much, vapor will be released into the atmosphere from the release pipe that communicates with the underground tank of the fuel supply device.

[0003] Here, the back pressure of the VR system is roughly equal to the pressure in the underground tank, and the pressure in the underground tank fluctuates based on the temperature fluctuation throughout the day, the amount of fuel supplied to vehicles using the fuel supply device, etc. Therefore, the back pressure of the VR system also fluctuates. However, when the back pressure of the VR system fluctuates, the outlet pressure of the vapor recovery pump (VR pump) in the VR system also fluctuates, and the amount of vapor recovered also fluctuates. Therefore, it is difficult to adjust the amount of fuel dispensed and the amount of vapor recovered to be the same. And because the back pressure of the VR system fluctuates, it is difficult to prevent vapor from being released into the atmosphere with a fueling device using a conventional VR system. For this reason, in a fuel supply device having a VR system, it is desirable to keep the outlet pressure of the VR pump constant, but this has not yet been proposed in the prior art. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2-219794 [Patent Document 2] JP 2014-58341 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been proposed in view of the above-mentioned problems with the conventional technology, and has an object to provide a fuel supply device capable of keeping the outlet pressure of the VR pump constant. [Means for solving the problem]

[0006] The oil supply device (100) of the present invention comprises: A vapor recovery line (1:VR line) is provided which is connected from the fuel supply nozzle (6) to the fuel storage tank (5) in order to return the vapor generated during fuel supply to the fuel storage tank (5), The vapor recovery line (1) is equipped with a vapor recovery pump (2: VR pump) that sucks in (pressurizes) and discharges vapor. In order to keep the outlet pressure of the vapor recovery pump (2) constant and to equalize the amount of fuel supplied and the amount of vapor recovered, This system is characterized in that a (e.g., mechanical) back pressure regulating valve (3) having a function of maintaining the pressure on the discharge port side of the vapor recovery pump (2) at a set value is interposed in the region of the discharge side of the vapor recovery pump (2) of the vapor recovery line (1).

[0008] Also The fuel supply device (100-2) of the present invention is The above a pressure sensor (7) or a pressure switch is provided in an outlet region of the back pressure regulating valve (3) of the vapor recovery line (1-2) and has a function of measuring the pressure in the region (the outlet region of the back pressure regulating valve 3 of the vapor recovery line 1-2) and transmitting the measured pressure to a control device (10); The control device (10) has a function of activating a warning means and / or stopping the refueling operation when the pressure in the outlet side region of the back pressure regulating valve (3) of the vapor recovery line (1-2) (the back pressure of the VR system) reaches or exceeds a pressure at which the back pressure regulating valve (3) cannot maintain the pressure on the discharge port side of the vapor recovery pump (2) at a set value (when the back pressure of the VR system reaches or exceeds a pressure at which the inlet side pressure of the back pressure regulating valve 3 cannot be maintained at a set value). It is preferable that Effect of the Invention

[0009] According to the present invention having the above-mentioned configuration, since the back pressure regulating valve (3) is provided on the discharge side of the VR pump (2) of the VR line (1), even if the inlet pressure of the VR pump (2) (i.e., the suction pressure of the VR pump 2) and the back pressure of the VR system fluctuate, the inlet pressure of the back pressure regulating valve (3) or the discharge port pressure of the VR pump (2) always remains at a set pressure. Therefore, when refueling a vehicle (C), for example, with the fuel supply device (100) of the present invention, the amount of fuel supplied and the amount of vapor recovered are the same, and vapor is prevented from being released into the atmosphere from the fuel supply port of a tank (not shown) of the vehicle C, or from being released into the atmosphere from the discharge pipe (8).

[0010] In addition, in the present invention, if the back pressure of the VR system (20-1) (pressure at the outlet side of the VR pump 2) is measured by a pressure sensor (7 or a pressure switch) instead of installing the back pressure regulating valve (3), the back pressure of the VR system (20-1) (pressure at the outlet side of the VR pump 2) can be monitored by the pressure sensor (7), the measurement result of the pressure sensor (7) can be transmitted to the control device (10), and the rotation speed of the VR pump (2) can be controlled (by controlling the pump drive motor 9) in response to the back pressure of the VR system (20-1) measured by the pressure sensor (7). This makes it possible to stably control the amount of vapor suction by the VR pump (2). As a result, it becomes possible to control the amount of fuel supplied and the amount of vapor collected to be equal, and it is possible to prevent vapor from being discharged into the atmosphere from the fuel filler port of the tank (not shown) of the vehicle C and from being discharged into the atmosphere from the discharge pipe (8).

[0011] Furthermore, in the present invention, if the back pressure of the VR system (20-2) (the pressure at the outlet side of the back pressure regulating valve 3) is measured by a pressure sensor (7 or a pressure switch) in addition to the back pressure regulating valve (3), the pressure sensor (7) can detect an abnormality in which the back pressure of the VR system (20-2) exceeds the adjustment range of the back pressure regulating valve (3), and a warning can be displayed to an operator or refueling can be stopped when such an abnormality occurs. Therefore, when the back pressure of the VR system (20-2) increases abnormally and the discharge pressure of the VR pump (2) exceeds the allowable range, a warning can be displayed to an operator or the refueling operation can be stopped to make the operator immediately aware of the abnormality, or refueling can be immediately forcibly stopped in the abnormality. This further improves the safety of the refueling operation. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a block diagram showing a first embodiment of the present invention. [Diagram 2] FIG. 2 is a front cross-sectional view showing an example of a back pressure regulating valve used in the first embodiment. [Diagram 3] FIG. 3 is an explanatory diagram showing the arrangement of a back pressure regulating valve and a vapor recovery pump in FIG. 2. [Figure 4] FIG. 4 is a characteristic diagram showing the characteristics of the inlet side pressure and the outlet side pressure of the back pressure regulating valve. [Diagram 5] FIG. 4 is a block diagram showing a second embodiment of the present invention. [Figure 6] 10 is a flowchart showing a control in a second embodiment. [Figure 7] FIG. 11 is a block diagram showing a third embodiment of the present invention. [Figure 8] 13 is a flowchart showing a control in a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. First, a first embodiment of the present invention will be described with reference to FIGS. In FIG. 1 showing the overall configuration of the first embodiment, the refueling device, generally designated by the reference symbol 100, includes a VR line 1 (vapor recovery line), a VR pump 2 (vapor recovery pump), a pump drive motor 9, a back pressure regulating valve 3, a fuel storage tank 5, a refueling nozzle 6, a control device 10 described later, and a VR system 20 (vapor recovery system). The VR line 1 is connected from a fuel supply nozzle 6 to a fuel storage tank 5 in order to return the vapor generated during refueling to the fuel storage tank 5. A VR pump 2 and a back pressure regulating valve 3 are installed in the VR line 1. In FIG. 1, the flow of vapor is indicated by arrow V. The VR pump 2 has the function of sucking in vapor from the fuel supply nozzle 6 side, pressurizing it, and discharging it. The back pressure regulating valve 3 is interposed in the region of the discharge side of the VR pump 2 in the VR line 1, and has the function of maintaining the pressure on the discharge port side of the VR pump 2 at a set value. Here, the VR pump 2 is driven by a pump drive motor 9.

[0014] The refueling device 100 has a refueling line 31 that communicates from a fuel storage tank 5 to a refueling nozzle 6 in order to refuel a fuel tank (not shown) of a vehicle C, and a refueling pump 32 and a flow meter 34 are installed in the refueling line 31. The refueling pump 32 is driven by a refueling motor 33. The direction in which the fuel flows in the refueling line 31 is indicated by an arrow F. The fuel supply device 100 also includes a discharge pipe 8 for discharging the vapor into the atmosphere when the amount of recovered vapor is large. The fuel supply device 100 includes a control device 10 that executes fuel supply control and control of the VR system 20 . The control device 10 receives a measured flow rate from the flowmeter 34 via a signal line SL1 for refueling control, and transmits a control signal to the refueling motor 33 via a signal line SL2. Also, for control of the VR system 20, it transmits a control signal to the pump drive motor 9 via a signal line SL3. Information such as the amount of refueling provided by the control device 10, emergency warning information, and others are displayed on a display 11. In FIG. 1, reference numeral 12 denotes a nozzle switch, and reference numeral 13 denotes a nozzle hook.

[0015] In FIG. 1, the VR pump 2 uses a positive displacement rotary pump. The reason why a positive displacement rotary pump is used is that a vane pump, which is an example of a positive displacement rotary pump, has a clearance on the side (due to the rotation of the rotor). Gas leaks from the high pressure side (discharge side) to the low pressure side (suction side) through the clearance. In other words, if there is no leakage from the rotor top (clearance at the end face side) (if there is no clearance from the rotor top), the rotor will not rotate. In the first embodiment, a back pressure regulating valve 3 is provided to deal with the case where the discharge rate decreases and the pressure at the pump outlet drops due to the above-mentioned leakage.

[0016] In contrast, in the case of a pump that is not a rotary pump, such as a reciprocating piston pump, leakage as occurs in the vane pump described above does not exist, and there is no need to consider a drop in pump outlet pressure due to such leakage. Furthermore, there may be regulations that require the air (vapor) / liquid (gasoline) ratio (A / L ratio) at the tip of the filling nozzle to be within the range of 98 to 102 over the entire range of gasoline flow rates, but reciprocating piston pumps produce pulsation, which can cause discomfort to users when the flow rate during refueling is small. In contrast, rotary pumps are controlled by the rotation speed of the pump drive motor, so by lowering the rotation speed, it is possible to suck in air with less pulsation, allowing continuous sucking even at small flow rates. For the above reasons, in the illustrated embodiment, a rotary pump is selected as the VR pump 2. Furthermore, in the illustrated embodiment, a vane pump, which is structurally simple and versatile, is selected as the positive displacement rotary pump. However, it is also possible to use a volumetric rotary pump other than the vane pump, such as a trochoid pump or a rotary pump. It is also possible to use a reciprocating piston pump by providing a valve that can control not only the rotation speed but also the A / L ratio.

[0017] The back pressure regulating valve 3 shown in FIG. 1 will be described in detail with reference to FIG. In FIG. 2, the back pressure regulating valve 3 is a mechanical valve and has a main body 3A, an inlet 3B, an outlet 3C, a primary pressure chamber 3D, a secondary pressure chamber 3E, a diaphragm 3F, a spring 3G, a pressure adjusting screw 3H, and an atmospheric pressure introducing hole 3I. The inlet 3B communicates with the discharge port of the VR pump 2 (Fig. 1) via the VR line 1 (Fig. 1), and the outlet 3C communicates with the oil storage tank 5 (Fig. 1) via the VR line 1. A protrusion 3J that protrudes upward in Fig. 2 is formed near the center of the main body 3A of the back pressure regulating valve 3, and the upper end of the protrusion 3J forms a valve seat 3K. The stem 3L formed integrally with the diaphragm 3F functions as a valve body, and together with the valve seat 3K of the protrusion 3J, forms a valve mechanism 3M. In Fig. 2, the flow direction of the fluid (fuel) inside the back pressure regulating valve 3 is indicated by an arrow A1 on the inflow side and an arrow A2 on the outflow side. The back pressure regulating valve 3 can adjust the elastic repulsive force of the spring 3G by adjusting the pressure adjusting screw 3H (the amount of screwing), thereby adjusting the force pressing the diaphragm 3F and stem 3L against the valve seat 3K. As a result, when the fluid in the primary pressure chamber 3D reaches or exceeds a predetermined pressure setting, it passes through the valve mechanism 3M, flows into the secondary pressure chamber 3E, and is discharged from the outlet 3C of the back pressure regulating valve 3 to the oil storage tank 5 side (arrow A2). With this configuration, the pressure of the fluid (fuel) in the primary pressure chamber 3D (suction side pressure: pressure in the area on the VR pump 2 side) can be constantly maintained at a predetermined setting. In addition, since the pressure inside the fuel tank 5 is expected to fluctuate due to temperature differences and the use of the fuel supply device (fueling a vehicle, etc.), the discharge pressure of the back pressure regulating valve 3 will not be the same as the pressure inside the fuel tank 5, but it will be approximately equal.

[0018] The back pressure regulating valve 3 shown in FIG. 2 is provided in a region of the VR line 1 (vapor recovery line) on the discharge side of the VR pump 2 (vapor recovery pump) (see FIGS. 1 and 3). In Fig. 3, the inlet 2A of the VR pump 2 communicates with the fuel supply nozzle 6 side (Fig. 1), the outlet 2B communicates with the inlet 3B of the back pressure regulating valve 3, and the outlet 3C of the back pressure regulating valve 3 communicates with the fuel storage tank 5 (Fig. 1). In Fig. 3, the arrow A indicates the flow direction of the fluid (fuel). By installing the back pressure regulating valve 3 on the discharge side (outlet side) of the VR pump 2 of the VR line 1, the pressure on the inlet side of the back pressure regulating valve 3 (or the retained pressure of the fluid in the primary pressure chamber 3D of the back pressure regulating valve 3: see Figure 2) in the region of the discharge side of the VR pump 2 of the VR line 1 is maintained at the set value.

[0019] Next, the relationship between the pressure on the inlet side of the back pressure regulating valve 3 (i.e., the pressure on the discharge port side of the VR pump 2) and the pressure on the outlet side of the back pressure regulating valve 3 (i.e., the back pressure of the VR system 20) will be described with reference to Fig. 4. In Fig. 4, the horizontal axis represents the back pressure of the VR system 20 (the outlet pressure of the back pressure regulating valve in the illustrated embodiment), and the vertical axis represents the pressure on the discharge port side of the VR pump 2 (the inlet pressure of the back pressure regulating valve in the illustrated embodiment). First, when no back pressure regulating valve is installed (as in the case of the prior art), the relationship between the pressure on the discharge port side of the VR pump and the back pressure of the VR system is as shown by characteristic line B in Figure 4 (2). According to characteristic line B in Fig. 4(2), as the back pressure of the VR system 20 fluctuates (rises), the pressure on the discharge side of the VR pump 2 gradually fluctuates (rises). Here, the back pressure of the VR system 20 is the pressure inside the oil storage tank 5, and the pressure inside the oil storage tank 5 fluctuates due to the difference in temperature between morning and afternoon and the drop in the oil level in the underground tank caused by the use of a fuel supply device (fueling a vehicle, etc.), and the back pressure of the VR system 20 also fluctuates. Note that the symbol α in Fig. 4(2) indicates the boundary of the range in Fig. 4(1) described later in which the outlet pressure of the VR pump (the inlet pressure of the back pressure regulating valve) does not exceed the set value, but is also shown in Fig. 4(2) for reference. As is clear from characteristic line B in Figure 4 (2) (characteristic line for a conventional VR system), in the conventional technology, the discharge pressure (outlet pressure) of the VR pump 2 varies depending on the back pressure of the VR system 20, so the amount of vapor collected from the fuel supply nozzle 6 also varies. Therefore, it is difficult to make the amount of fuel supplied and the amount of vapor collected the same, and it is also difficult to prevent vapor from being released into the atmosphere during fuel supply.

[0020] FIG. 4(1) shows, in the illustrated embodiment, the relationship between the pressure on the inlet side of the back pressure regulating valve 3 (i.e., the pressure on the discharge port side of the VR pump 2) and the pressure on the outlet side of the back pressure regulating valve 3 (i.e., the back pressure of the VR system 20) as characteristic line A. As shown by characteristic line A in Figure 4 (1), in the region where the pressure on the outlet side of the back pressure regulating valve 3, i.e., the back pressure of the VR system 20, does not exceed the allowable range (the region to the left of symbol α in Figure 4), the pressure on the inlet side of the back pressure regulating valve 3, i.e., the pressure on the discharge port side of the VR pump 2, is always maintained at a predetermined set value. The dashed characteristic line shown in addition to characteristic line A is an imaginary line of the above relationship when the back pressure regulating valve 3 is not provided. According to the illustrated embodiment having the characteristic shown by the characteristic line A in Fig. 4 (1), even if the inlet pressure of the VR pump 2 (i.e., the suction pressure of the VR pump 2) fluctuates, the pressure on the discharge port side of the VR pump 2 (or the inlet pressure of the back pressure regulating valve 3) is always at the set pressure, so that the amount of vapor recovery can be easily and accurately adjusted, and it is possible to make the amount of fuel supplied and the amount of vapor recovery equal. Therefore, the amount of fuel supplied is prevented from becoming greater than the amount of vapor recovery, and vapor is prevented from being released into the atmosphere from the fuel filler port of the vehicle tank. In addition, the amount of vapor recovery is prevented from becoming greater than the amount of fuel supplied, and vapor is prevented from being released into the atmosphere from the release pipe 8.

[0021] Next, a second embodiment of the present invention will be described with reference to FIGS. In the first embodiment (see FIGS. 1 to 4), a back pressure regulating valve 3 is provided on the discharge side of the VR pump 2 to keep the outlet pressure of the VR pump 2 constant, but in the second embodiment of FIG. 5, no back pressure regulating valve is provided. 5, no back pressure regulating valve is provided as described above. In the second embodiment, a pressure sensor 7 is installed in the area of ​​the discharge side of the VR pump 2 of the VR line 1-1 to monitor the back pressure of the VR system 20-1 (the pressure on the discharge side of the VR pump 2) and transmit the measurement result of the pressure sensor 7 to the control device 10. The control device 10 has a function of controlling the rotation speed of the VR pump 2 in response to the back pressure of the VR system 20-1 measured by the pressure sensor 7, thereby stably controlling the amount of vapor suction from the fuel filling nozzle 6 side. In the description of the second embodiment with reference to Figures 5 and 6, the configuration and effects different from those of the first embodiment shown in Figures 1 to 4 will be mainly described. In this description, components similar to those of the first embodiment (VR pump 2, oil storage tank 5, oil supply nozzle 6, control device 10, etc.) will be described with the same reference numerals.

[0022] 5, a refueling device according to the second embodiment, generally designated by reference numeral 100-1, includes a VR line 1-1 communicating from a refueling nozzle 6 to a fuel storage tank 5, a fuel supply line 31 communicating from the fuel storage tank 5 to the refueling nozzle 6, a discharge pipe 8 for discharging vapor into the atmosphere, and a control device 10 for executing refueling control and other controls. The fuel supply line 31 and the discharge pipe in the second embodiment are similar to those in the first embodiment, including the devices installed therein. As in the first embodiment, a VR pump 2 that draws in vapor, pressurizes it, and discharges it is installed in the VR line 1-1. The second embodiment differs from the first embodiment in that a pressure sensor 7 (or a pressure switch) is installed in the VR line 1-1 in an area on the discharge side of the VR pump 2. The pressure sensor 7 has a function of measuring the pressure in the area on the discharge side of the VR pump 2 in the VR line 1-1 (i.e., the back pressure of the VR system 20-1) and a function of transmitting the measurement result to the control device 10 via a signal line SL4.

[0023] In the second embodiment, the control device 10 has a function of controlling the rotation speed of the VR pump 2 based on, for example, the "VR system back pressure - vapor suction flow rate by the VR pump" characteristic (pre-stored characteristic). That is, the control device 10 has a function of determining the rotation speed of the VR pump 2 so that the amount of fuel supply and the amount of vapor recovery are equal based on the "VR system back pressure - vapor suction flow rate by the VR pump" characteristic from the pressure in the area on the discharge side of the VR pump 2 measured by the pressure sensor 7 (the back pressure of the VR system 20-1). The control device 10 has a function of transmitting a control signal to the pump drive motor 9 via the signal line SL3 to control the rotation speed of the VR pump 2 to a rotation speed at which the amount of fuel supply and the amount of vapor recovery are equal. This function of the control device 10 makes it possible to stabilize the amount of vapor suction by the VR pump 2 and control it so that the amount of fuel supply and the amount of vapor recovery are equal. Here, instead of the above characteristics, the control device 10 can use an equation showing the relationship between the VR system back pressure and the vapor suction flow rate by the VR pump to calculate from the pressure in the discharge side area of ​​the VR pump 2 (back pressure of the VR system 20-1) measured by the pressure sensor 7, and control the rotation speed of the VR pump 2 to a rotation speed at which the amount of fuel supplied and the amount of vapor recovered are equal.

[0024] The control in the second embodiment will be described mainly with reference to FIG. 6, in step S1, the pressure in the region of the VR line 1-1 on the discharge side of the VR pump 2 is measured. The pressure measurement in step S1 is performed by the pressure sensor 7, and the measurement result is transmitted to the control device 10 via the signal line SL4. In step S2, based on the pressure in the region on the discharge side of the VR pump 2 (the back pressure of the VR system 20-1) measured in step S1, the rotation speed of the VR pump 2 suited to the pressure measured is determined. As described above, the manner of determining the rotation speed of the VR pump 2 is, for example, to determine the rotation speed of the VR pump 2 so that the amount of fuel supplied and the amount of vapor collected are equal, taking into consideration the "back pressure of the VR system - vapor suction flow rate by the VR pump" characteristic determined in advance. Then, the process proceeds to step S3. In step S2, instead of storing the "back pressure of the VR system - vapor suction flow rate by the VR pump" characteristic, the rotation speed of the VR pump 2 may be determined by calculation by the control device 10 using an arithmetic expression corresponding to the characteristic.

[0025] In step S3, the VR pump 2 is controlled to operate at the rotation speed determined in step S2, and then the process returns to step S1 to continue the control. In FIG. 6, when the control is to be ended, it is sufficient to end the control without returning at step S3. Other configurations and effects of the second embodiment in FIGS. 5 and 6 are similar to those of the first embodiment in FIGS.

[0026] A third embodiment of the present invention will be described with reference to FIGS. The third embodiment in Figures 7 and 8 is provided with the back pressure regulating valve 3 in the first embodiment (Figures 1 to 4), and also has a pressure sensor 7 (or a pressure switch) similar to that in the second embodiment (Figures 5 and 6) interposed in the outlet side region of the back pressure regulating valve 3 of the VR line 1-2. The third embodiment in FIG. 7 has a back pressure regulating valve 3 like the first embodiment, but the back pressure of the VR system 20-2 (the pressure on the outlet side of the back pressure regulating valve 3) is measured by a pressure sensor 7, and if the back pressure of the VR system 20-2 exceeds the adjustment range of the back pressure regulating valve 3, the pressure sensor 7 detects this and displays a warning to the person filling the tank or stops filling the tank. In the following description of the third embodiment, the configuration and operation different from those of the first and second embodiments will be mainly described. In this regard, components similar to those of the first and second embodiments (VR pump 2, back pressure regulating valve 3, fuel storage tank 5, fuel supply nozzle 6, sensor 7, control device 10, etc.) will be described with the same reference numerals.

[0027] 7, a refueling device according to a third embodiment generally designated by reference numeral 100-2 includes a VR line 1-2 communicating from a refueling nozzle 6 to a fuel storage tank 5, a fuel supply line 31 communicating from the fuel storage tank 5 to the refueling nozzle 6, a discharge pipe 8 for discharging vapor into the atmosphere, and a control device 10 for executing refueling control, etc. The fuel supply line 31, the discharge pipe 8, etc. in the third embodiment are similar to those in the first and second embodiments, including their intervening members. A VR pump 2 is provided in the VR line 1-2, as in the first and second embodiments. A mechanical back pressure regulating valve 3 having a function of maintaining the pressure on the discharge port side of the VR pump 2 at a set value is provided in the discharge side area of ​​the VR pump 2 in the VR line 1-2, as in the first embodiment. In the third embodiment, unlike the first embodiment, a pressure sensor 7 (or a pressure switch) is provided in the VR line 1-2 in an area on the outlet side of the back pressure regulating valve 3. The pressure sensor 7 has a function of measuring the pressure in the area on the outlet side of the back pressure regulating valve 3 in the VR line 1-2 (the back pressure of the VR system 20-2) and transmitting the measurement result of the pressure to the control device 10 via the signal line SL4.

[0028] In FIG. 7, when the pressure in the outlet region of the back pressure regulating valve 3 (the back pressure of the VR system 20-2) exceeds the allowable range, the back pressure regulating valve 3 is no longer able to maintain the pressure on the discharge side of the VR pump 2 (the pressure on the inlet side of the back pressure regulating valve 3) at the set value, and the pressure on the discharge side of the VR pump 2 (the pressure on the inlet side of the back pressure regulating valve 3) becomes higher than the set value. In other words, the allowable range of the pressure in the outlet region of the back pressure regulating valve 3 (the back pressure of the VR system 20-2) is the range within which the back pressure regulating valve 3 can maintain the pressure on the outlet side of the VR pump 2 (the inlet side pressure of the back pressure regulating valve 3) at a set value, and this allowable range is determined in advance and stored in the control device 10. The control device 10 compares the measurement result of the pressure in the outlet area of ​​the back pressure regulating valve 3 (back pressure of the VR system 20-2) obtained from the pressure sensor 7 with the "allowable range," and if the pressure in the outlet area of ​​the back pressure regulating valve 3 (back pressure of the VR system 20-2) falls outside the allowable range and the back pressure regulating valve 3 is no longer able to maintain the pressure on the discharge side of the VR pump 2 (the inlet side pressure of the back pressure regulating valve 3) at the set value, it has the function of activating a warning means (not shown) and / or stopping the refueling operation. On the other hand, if the pressure measurement result is within the allowable range, the pressure on the discharge side of the VR pump 2 (the inlet side pressure of the back pressure regulating valve 3) is maintained at the set value, and the refueling operation is continued while controlling the rotation speed of the VR pump 2 so that the amount of fuel supplied and the amount of vapor recovered are equal.

[0029] Control in the third embodiment will be described mainly with reference to FIG. 8, in step S11, the back pressure of the VR system 20-2 (the pressure in the area on the outlet side of the back pressure regulating valve 3) is measured in the VR line 1-2. The measurement is performed by the pressure sensor 7, and the measurement result of the pressure sensor 7 is transmitted to the control device 10 via the signal line SL4. In step S12, the back pressure of the VR system 20-2 measured in step S11 (pressure in the area on the outlet side of the back pressure regulating valve 3) is compared with the allowable range previously stored in the control device 10. As described above, the allowable range of the back pressure of the VR system 20-2 is the range of back pressure (of the VR system 20-2) at which the back pressure regulating valve 3 can hold the pressure on the outlet side of the VR pump 2 (the pressure on the inlet side of the back pressure regulating valve 3) at a set value. If the comparison result in step S12 indicates that the back pressure of the VR system 20-2 (pressure in the area on the outlet side of the back pressure regulating valve 3) exceeds the allowable range (greater than the upper limit of the allowable range: step S12 is "Yes"), proceed to step S13. On the other hand, if the back pressure of the VR system 20-2 (pressure in the area on the outlet side of the back pressure regulating valve 3) is within the allowable range (equal to or less than the upper limit of the allowable range: step S12 is "No"), return to step S11. The comparison in step S12 is performed by the controller 10.

[0030] In step S13 (step S12 is "Yes": if it is determined that the back pressure of the VR system 20-2 (the pressure in the area on the outlet side of the back pressure regulating valve 3) exceeds the allowable range), it is determined that it is difficult to make the amount of fuel dispensed equal to the amount of vapor recovered, and there is a risk that the vapor being dispensed may be released into the atmosphere, so a warning means (not shown) is activated to issue a warning to the person dispenser. At that time, instead of or in addition to the warning, the refueling device 100-2 can also be controlled to stop the refueling operation. The warning and / or control to stop the refueling operation is executed by the control device 10. If the back pressure of the VR system 20-2 (the pressure in the area on the outlet side of the back pressure regulating valve 3) is within the allowable range (step S12 is "No"), the process returns to step S11, the pressure on the outlet side of the VR pump 2 (the pressure on the inlet side of the back pressure regulating valve 3) is maintained at the set value, and the refueling operation is continued while controlling the rotation speed of the VR pump 2 so that the amount of fuel supplied and the amount of vapor recovered are equal. Other configurations and effects of the third embodiment in FIGS. 7 and 8 are similar to those of the first embodiment in FIGS.

[0031] It should be noted that the illustrated embodiment is merely an example and is not intended to limit the technical scope of the present invention. [Explanation of symbols]

[0032] 1, 1-1, 1-2...VR line (vapor recovery line) 2. VR pump (vapor recovery pump) 3. Back pressure regulating valve 5. Oil storage tank 6. Fuel nozzle 7. Pressure sensor 8...Emission tube 10. Control device 20, 20-1, 20-2...VR system (vapor recovery system) 100, 100-1, 100-2...Fueling device

Claims

1. A vapor recovery line is provided that connects the fuel nozzle to the fuel storage tank in order to return the vapor generated during refueling to the fuel storage tank. The vapor recovery line is equipped with a vapor recovery pump that sucks in and discharges vapor. A fuel supply device characterized in that a back pressure regulating valve having a function of maintaining the pressure on the discharge port side of the vapor recovery pump at a set value is interposed in the region of the vapor recovery pump discharge side of the vapor recovery line so that the outlet pressure of the vapor recovery pump can be kept constant to equalize the amount of fuel supplied and the amount of vapor recovered.

2. A pressure sensor having a function of measuring the pressure in an outlet region of the back pressure regulating valve of the vapor recovery line and transmitting the measured pressure to a control device is interposed, The refueling device of claim 1, wherein the control device has a function of activating a warning means and / or stopping the refueling operation when the pressure in the area on the outlet side of the back pressure regulating valve of the vapor recovery line reaches or exceeds a pressure at which the back pressure regulating valve cannot maintain the pressure on the discharge port side of the vapor recovery pump at a set value.

Images