JP6617115B2 - Water detector, fuel supply control method, and water contamination monitoring system - Google Patents

Description

  The present invention relates to a water detection device, a fuel supply control method, and a water mixing monitoring system, for example, a device that detects water mixed in fuel supplied to a meter from a petroleum fuel tank buried underground in a gas station. The present invention relates to a fuel supply control method and a monitoring system.

  Underground tanks are buried in gas stations such as gas stations. In response to unloading (lubrication) of fuel oil such as gasoline, light oil and kerosene from a tanker truck, the fuel oil is stored in the underground tank. Then, each metering machine (oiling machine) connected by piping from the underground tank uses the fuel spill pump in the metering machine to control the fuel oil stored in the underground tank under the control of a POS (point of sales) terminal. The fuel oil sucked up is supplied to the vehicle.

  In such facilities, the fuel oil supplied from the underground tank may contain water. As the cause, for example, when water is mixed when unloading from a tank truck, or / and ground water mixed due to a crack in a pipe connecting the underground tank and the ground is assumed. For this reason, a water detector is arranged in the weighing machine so as not to supply fuel oil mixed with such moisture to the vehicle, and an alarm is output when moisture is detected (for example, see Patent Document 1). Here, according to the provisions of the Fire Service Law, when replacing an existing weighing machine with a new weighing machine, it is necessary to replace all the parts in the existing weighing machine. Therefore, even when the water detection device arranged in the weighing machine is still sufficiently usable, there is a problem that the water detection device needs to be replaced in the same manner every time the weighing machine is replaced.

  Furthermore, when the water detection device is arranged in the weighing machine, since the path from the detection of moisture to the fuel nozzle serving as the discharge port to the vehicle is short, the time from when moisture is detected until the water reaches the fuel nozzle The time is short. Therefore, an urgent countermeasure is required to prevent moisture from reaching the refueling nozzle in such a short time.

  Here, a pair of electrodes for performing water detection by measuring the dielectric constant of the fuel flowing between the electrodes may be provided in the weighing machine, or in underground underground piping for sending fuel from the underground tank to the weighing machine (For example, see Patent Document 2).

JP, 2006-008048, A JP2015-004682A

  However, in the method of measuring the dielectric constant of the fuel flowing between the electrodes by arranging a pair of electrodes in the fuel, even if a pair of electrodes are provided in the underground buried pipe, water and air are mixed in the fuel There was a problem that the measurement accuracy deteriorated. In addition, although the technique of patent document 1 mentioned above has shown the case where a water detection apparatus is arrange | positioned in a measuring machine, the recessed part which opposes the flow of a fuel is provided in a water detection apparatus, it remove | deviates from a main flow, and in this recessed part A part of the fuel that has flowed in is used to measure the dielectric constant by separating water from the part of the fuel. However, with this method, the amount of fuel used for water detection is small relative to the mainstream fuel, and there is a risk that an error will occur in detection accuracy. Therefore, it is desirable to use mainstream fuel as a detection target.

  Conventionally, when moisture is detected, an alarm output to that effect is performed. However, such an alarm has a problem that fuel containing moisture may be erroneously supplied to the vehicle.

  Therefore, one embodiment of the present invention provides a water detection device that can eliminate the need for replacement of the water detection device even when the weighing machine is replaced while accurately detecting moisture. In addition, another aspect of the present invention provides a fuel supply control method and a monitoring system that can avoid accidentally supplying fuel mixed with moisture to a vehicle.

The water detection device according to one aspect of the present invention includes:
An electrically conductive material having a horizontal piping part that forms part of a flow path that sends fuel to a measuring machine that supplies fuel to a vehicle from an underground tank in which fuel is stored in a fuel filling station. The piping unit used,
The flow path is located in the horizontal flow path in the horizontal pipe section upstream from the position where the direction changes from the horizontal direction, and is positioned at a position lower than the center height position of the horizontal pipe section. Electrodes,
A measuring unit for measuring the capacitance between the electrode and the piping unit;
A determination unit that determines whether or not moisture is mixed in the fuel using the measured capacitance value;
With
The piping unit and the electrode described above are arranged in a piping connection pit under the weighing machine and at least partially buried underground.

  In addition, it is preferable that the pipe further includes a circumferential pipe section that forms a flow path for sending fuel along the circumferential direction from a position higher than the horizontal flow path toward the horizontal flow path. .

  Further, it is preferable that the connection port on the underground tank side and the connection port on the weighing machine side of the piping unit are formed substantially coaxially in one direction.

  In addition, it is preferable that the determination unit determines that a water pool has occurred in the piping unit when the capacitance is not measurable as a result of the measurement.

Further, a sensor for measuring the flow rate of the fuel flowing in the piping unit is further provided,
It is preferable to change the threshold value of the capacitance for determining that water is mixed in the fuel according to the measured flow velocity.

A fuel supply control method according to an aspect of the present invention includes:
In a fuel supply control method in the case of supplying fuel stored in an underground tank installed in a fuel filling station to a vehicle via a measuring machine arranged on the ground,
Using the water detection device described above, detecting water in the fuel supplied from the underground tank to the weighing machine,
A step of stopping the supply of fuel from the weighing machine to the vehicle when moisture in the fuel is detected;
It is provided with.

The water contamination monitoring system according to one aspect of the present invention includes:
An electrode disposed in a horizontal flow path of fuel supplied to the weighing machine in a pipe connection pit under the weighing machine at the fuel filling station and at least partially buried underground;
Piping constituting the horizontal flow path;
A measurement unit for measuring the capacitance between the electrode and the pipe;
A determination unit that determines whether or not moisture is mixed in the fuel using the measured capacitance value;
A POS (point of sales) terminal that controls the weighing machine is connected to the weighing machine in a relayable manner, and when the determination unit determines that moisture is mixed in the fuel, it is independent of the control signal from the POS terminal. A control unit for controlling the weighing machine to stop the supply of fuel to the vehicle;
Equipped with a,
The electrode is disposed at a position in the horizontal flow path on the upstream side of the position where the flow path changes direction from the horizontal direction,
The piping further forms a flow path for sending the fuel along a circumferential direction from a position higher than the horizontal flow path toward the horizontal flow path .

  According to one aspect of the present invention, it is possible to eliminate the need to replace the water detection device even when replacing the weighing machine while accurately detecting moisture. Moreover, the other aspect of this invention can avoid supplying the fuel in which the water | moisture content was mixed into the vehicle accidentally. In addition, the existing POS terminal can be improved.

It is a figure which shows an example of a structure of the fuel filling station in Embodiment 1, and an example of a structure of a water mixing monitoring system. It is a perspective view which shows an example of a structure of the piping unit of the water detection apparatus in Embodiment 1. FIG. It is the front view and side view which show an example of a structure of the piping unit of the water detection apparatus in Embodiment 1. FIG. 3 is a diagram for explaining a water detection method in the first embodiment. 3 is a diagram showing an example of a cross-sectional configuration in a horizontal pipe in the first embodiment. FIG. FIG. 6 is a diagram showing another example of a cross-sectional configuration in the horizontal pipe in the first embodiment. 6 is a diagram for explaining a fuel supply control method by the water mixing monitoring system in Embodiment 1. FIG. It is a figure which shows an example of a structure of the water detection apparatus arrange | positioned in the piping connection pit in Embodiment 2. FIG. 6 is a diagram showing an example of a cross-sectional configuration in a horizontal pipe in Embodiment 2. FIG.

Embodiment 1 FIG.
FIG. 1 is a diagram showing an example of the configuration of a fuel filling station and an example of the configuration of a water mixing monitoring system in the first embodiment. In FIG. 1, a storage tank 102 (underground tank) is buried underground (underground) in a fuel filling station represented by a gas station. On the other hand, a weighing machine (oiling device) 104 is arranged on the ground. A pipe inlet 116 that receives unloading (lubrication) of fuel oil from the tank truck 106 is disposed on the ground. The storage tank 102 and the weighing machine 104 are connected by a pipe 112 buried underground. The storage tank 102 and the pipe inlet 116 are connected by a pipe 114 buried underground. The weighing machine 104 is arranged on a base 103 made of, for example, concrete material. And the center part of the base 103 is opened, and the piping connection pit 113 by which at least one part was embed | buried underground is installed in the opening part of the base 103. FIG. In other words, the pipe connection pit 113 is installed under the weighing machine 104. The pipe connection pit 113 generally provides a box-shaped internal space surrounded by a metal plate such as an iron material. A pipe 112 connected to the storage tank 102 and extending toward the weighing machine 104 with a slight inclination from the horizontal direction to the upper side is inserted into the pipe connection pit 113, and the pipe 112 is connected to the pipe connection pit 113. Is turned upward and connected to the weighing machine 104 installed on the pipe connection pit 113.

  As described above, the fuel oil supplied from the storage tank 102 may contain moisture. Therefore, in Embodiment 1, the water mixing monitoring system 500 is arrange | positioned in a fuel filling station. The water mixing monitoring system 500 disposed in such a fuel filling station includes a water detection device 100 and a meter control circuit 60. The water detection apparatus 100 includes a piping unit 10, an electrode 12 described later, and a control panel 50. In the control panel 50, a measurement circuit 56 and a determination circuit 54 are arranged. Each “˜circuit” such as the measurement circuit 56 and the determination circuit 54 may be configured by a computer or the like that executes software such as a program. Or you may comprise with an electronic circuit etc. Alternatively, a combination thereof may be used. In other words, each “˜circuit” has a processing circuit. Examples of the processing circuit include an electric circuit, a computer, a processor, a circuit board, or a semiconductor device. Each “˜circuit” may use a common processing circuit (the same processing circuit), or may use different processing circuits (separate processing circuits). Input data necessary for the measurement circuit 56 and the determination circuit 54 or the calculated result may be stored in a memory (not shown) each time. In the control panel 50, an interface circuit (not shown) for inputting or outputting information from the outside is disposed.

  As shown in FIG. 1, the pipe of the water detection device 100 between a pipe 112 extending upward (z direction) in the pipe connection pit 113 and a pipe 115 extending downward (−z direction) from the weighing machine 104. Connect so as to sandwich the unit 10.

  Here, in addition to the gas station (GS) (or SS: service station) that sells fuel oil, such as gasoline, light oil, and kerosene, to the general vehicle 300, the transportation company, etc. has its own business. The refueling place which supplies fuel oil to the vehicles (taxi, bus, truck, etc.) to be used is also included. In addition, the fuel oil referred to here may include liquefied natural gas, liquefied hydrogen, and the like.

  When the tank truck 106 arrives at the gas station, the piping of the tank truck 106 is connected to the pipe inlet 116. Thereafter, the fuel oil 101 carried by the tank truck 106 flows through the pipe 114 and is unloaded (lubricated) into the storage tank 102.

  The weighing machine 104 arranged on the ground pours (refuels) the fuel oil 101 stored in the storage tank 102 via the pipe 112 into the vehicle 300. For example, the fuel oil 101 stored in the storage tank 102 is transferred by a pump disposed in the weighing machine 104.

  Here, the weighing machine 104 is controlled by a POS (point of sales) terminal 200. In other words, the weighing machine 104 can be refueled upon receiving a refueling permission signal from the POS terminal 200, and pours (refuels) the fuel oil 101 into the vehicle 300. Then, the amount of fuel oil 101 supplied is measured by the weighing machine 104, and the result is output to the POS terminal 200. The POS terminal 200 calculates a fee that is commensurate with the amount of refueling and outputs it to the weighing machine 104. In this way, the user of the vehicle 300 pays a fee, for example, in cash. Alternatively, pay using a credit card. When a credit card is used, the card information is output to the POS terminal 200 via the weighing machine 104 and settlement is performed. In the first embodiment, as shown in FIG. 1, a weighing machine control circuit 60 is connected to the POS terminal 200 and the weighing machine 104 so as to be able to relay. Therefore, the weighing machine 104 is controlled by the POS terminal 200 via the weighing machine control circuit 60.

  Here, FIG. 1 shows a configuration necessary for explaining the first embodiment. For a gas station or / and a water contamination monitoring system, other necessary configurations may be provided.

FIG. 2 is a perspective view showing an example of a configuration of a piping unit of the water detection device in the first embodiment.
FIG. 3 is a front view and a side view showing an example of the configuration of the piping unit of the water detection device in the first embodiment. In FIG. 2, illustration of piping joints such as flanges provided at the upper and lower connection ports is omitted. 2 and 3, the piping unit 10 is configured by a combination of a piping material in a straight direction, an elbow piping material that bends 90 degrees, an elbow piping material that bends 45 degrees, and an elbow piping material that bends 180 degrees. The It goes without saying that the elbow piping material that bends the direction of 180 degrees may be constituted by a combination of elbow piping materials that bend the direction of 45 degrees or 90 degrees. In addition, each elbow piping material that bends the directions of 45 degrees, 90 degrees, and 180 degrees may be a piping joint that connects straight pipes. Further, in FIG. 3, there are places where the joints of the piping materials are not shown. In Fig.3 (a), a back | inner side shows ay direction toward drawing. In FIG.3 (b), the back side shows x direction toward drawing. In FIG. 3C, the near side toward the drawing indicates the y direction. In the example of FIG. 2, an elbow piping section that bends 90 degrees after forming a flow path upward (z direction) with a straight piping section 20 from the connection port side with the piping 112 from below (underground tank side). 21 to change the direction horizontally (−x direction). Then, after maintaining the horizontal flow path with the straight pipe section 22, the elbow pipe section 23 (circumferential pipe section) that bends the 180-degree direction changes the direction by 180 degrees while shifting so as not to hit the pipe section 20. Are connected to a straight pipe section 24 (horizontal pipe section) that forms a flow path in the horizontal direction (x direction). Then, after maintaining the horizontal flow path with the straight pipe section 24, the direction of the elbow pipe section 25 that bends 90 degrees is changed by 90 degrees, and the straight pipe section 26 that forms the flow path upward (z direction). Connected to. Then, the elbow piping section 27 that bends in the 45-degree direction changes the direction of 45 degrees toward the central axis of the flow path of the first piping section 20 and is connected to the straight piping section 28. Then, the elbow piping section 29 that bends in the 45-degree direction changes its direction by 45 degrees so as to be the same axis as the central axis of the flow path of the first piping section 20, and is connected to the straight piping section 30. Moreover, as shown to Fig.3 (a)-(c), the flange 31 used as an example of a piping joint is installed in the connection port end of the piping part 20 connected with the piping 112 from the downward direction (underground tank side). . A flange 32 as an example of a pipe joint is installed at the connection port end of the pipe part 30 connected to the pipe 115 from above (the weighing machine side).

  As described above, the piping unit 10 has a part of the flow path for sending the fuel oil 101 to the measuring machine 104 that supplies fuel to the vehicle 300 from the storage tank 102 (underground tank) in which the fuel oil 101 is stored in the fuel filling station. Constitute. The connection port of the piping unit 10 on the storage tank 102 (underground tank) side and the connection port on the weighing machine 104 side are formed substantially coaxially in one direction (substantially coaxial including some margin). Thereby, also in the existing gas station, the piping unit 10 of the water detection apparatus 100 can be easily attached without significantly changing the piping equipment.

  In the water detection device 100 according to the first embodiment, for example, the rod-shaped electrode 12 is inserted into the flow path horizontally (−x direction) from the outside of the elbow piping section 25, for example, and the straight piping section 24 (horizontal piping). Part) in the position in the horizontal flow path.

  FIG. 4 is a diagram for explaining the water detection method in the first embodiment. In FIG. 4, in the piping unit 10, a straight pipe part 24 (horizontal pipe part) and the pipe parts 23 and 25 before and after the pipe part 24 are shown, and the remaining pipe parts are not shown. The electrode 12 in Embodiment 1 is arrange | positioned in the position lower than the center height position of the piping part 24 (horizontal piping part). Then, the wiring 14 extending from the electrode 12 is connected to the measurement circuit 56. Then, the measurement circuit 56 (measurement unit) applies a measurement voltage between the electrode 12 and the piping unit 10 to measure the capacitance C between the electrode 12 and the piping unit 10. For example, a positive potential is applied to the electrode 12 and a ground potential is applied to the piping unit 10. Alternatively, the piping unit 10 may be grounded. As a material constituting the piping unit 10, a conductive material such as an iron material is used.

  In the case where moisture and air are mixed in the fuel oil 101, when the fuel oil 101 is transferred (suctioned) by a pump in the weighing machine 104, the fuel oil 101 in which moisture and air are mixed is in a turbulent state. Therefore, it flows in the piping 112 toward the weighing machine 104 side. Therefore, water particles and air (bubbles) flow in the fuel oil 101 in a dispersed state. The dielectric constant increases in the order of air, fuel oil 101, and water. Therefore, even if a pair of electrodes are arranged in the pipe 112 and the capacitance C between the electrodes is measured, in the state where air and water are mixed, the influence of water is offset by the influence of air, and moisture detection is difficult. Therefore, in the first embodiment, as shown in FIG. 4, the piping portion 24 (circumferential piping portion) causes the piping portion 24 (from the position higher than the horizontal flow path by the piping portion 24 (horizontal piping portion) ( A flow path for sending the fuel oil 101 along the circumferential direction is formed toward the horizontal flow path formed by the horizontal piping portion). When the fuel oil 101 is transferred (sucked) by the pump in the weighing machine 104, the fuel oil 101 in which moisture and air are mixed passes through the piping unit 10 at a flow velocity V. Therefore, centrifugal force acts on the oil component, moisture, and air component in the fuel oil 101, respectively. Specific gravity is large in order of air, fuel oil 101, and water. Therefore, the water with the highest specific gravity flows outside the circumferential flow path far from the center of the circle, the oil component flows in the middle of the circumferential flow path, and the air with the lowest specific gravity flows closer to the center side. The layers can be separated to flow inside the road. As a result, in the horizontal flow path in the piping part 24 (horizontal piping part) following the piping part 23, a position lower than the central height position of the piping part 24 can be passed through the moisture layer.

  FIG. 5 is a diagram showing an example of a cross-sectional configuration in the horizontal pipe in the first embodiment. In FIG. 5, the thickness of the piping is ignored. The capacitance C is most affected by the dielectric constant of an object existing between the electrodes with the shortest distance L. In Embodiment 1, since the electrode 12 is arranged at a position lower than the center height position of the piping part 24 (horizontal piping part), it exists between the electrode 12 and the bottom surface of the piping part 24 serving as the counter electrode. It can be configured to be most affected by the dielectric constant of moisture. As a result, the sensitivity when detecting moisture can be improved. Further, the influence of air in the fuel oil 101 can be eliminated.

  Next, in a state where the fuel oil 101 is not transferred (sucked) by the pump in the weighing machine 104, the centrifugal force does not act, but instead, the moisture having the highest specific gravity moves downward and the specific gravity is the lowest. Air moves upward. Therefore, even in such a case, the oil component layer, the moisture layer, and the air component layer can be separated in the horizontal flow path in the piping portion 24 (horizontal piping portion). Therefore, moisture can be collected between the electrode 12 that is between the electrodes of the narrowest distance L and the bottom surface of the piping portion 24. Therefore, even when the fuel oil 101 is not transferred (sucked), the sensitivity when detecting moisture can be improved. Further, the influence of air in the fuel oil 101 can be eliminated.

  The result measured by the measurement circuit 56 as described above is output to the determination circuit 54. The determination circuit 54 (determination unit) determines whether or not moisture is mixed in the fuel oil 101 using the measured capacitance value. Specifically, when the measured capacitance C is larger than the threshold Th, it may be determined that moisture is mixed in the fuel oil 101. The value of the threshold Th may be obtained in advance through experiments or the like. For example, it is preferable to set the threshold value Th to such an extent that it can be detected when the fuel oil 101 contains 5% or more of water. More preferably, the threshold value Th is set to such an extent that it can be detected when the fuel oil 101 contains 3% or more of water.

  FIG. 6 is a diagram showing another example of a cross-sectional configuration in the horizontal pipe in the first embodiment. FIG. 6 shows an example in which a water pool is generated between the electrode 12 and the bottom surface of the piping part 24 in a state where the fuel oil 101 is not transferred (sucked). When such a pool of water is accumulated up to a position where it touches the electrode 12, if a voltage is applied between the electrode 12 and the pipe portion 24, the conductive state is established, and the capacitance C cannot be measured. Therefore, the determination circuit 54 (determination unit) determines that a water pool has occurred in the piping unit 10 when the capacitance C is not measurable as a result of the measurement.

  Here, the upper limit of the height position of the electrode 12 may be a position lower than the center height position of the piping part 24 (horizontal piping part), and the lower limit includes 3 to 5% of water in the fuel oil 101. In such a case, it is preferable that the electrode 12 is in contact with a water reservoir that accumulates on the bottom surface of the pipe portion 24 during refueling stop.

  It should be noted that since the water layer separation proceeds more significantly in the stopped state, the value of the measured capacitance C becomes larger. Thus, the state which has stopped is more sensitive to water detection. Therefore, the value of the determination threshold Th may be different depending on whether the fuel oil 101 is flowing or stopped.

  As described above, in the first embodiment, water detection can be performed regardless of whether the fuel oil 101 is flowing or stopped. Furthermore, in Embodiment 1, since the fuel oil 101 is not stirred, the fuel oil 101 can be prevented from becoming clouded with air.

  As described above, in the first embodiment, the piping unit 10 and the electrode 12 are arranged in the piping connection pit 113 under the weighing machine 104 and at least partially buried underground. Therefore, the water detection device 100 can be arranged outside the weighing machine 104. Therefore, even when the weighing machine 104 is replaced, it is not regarded as a part of the weighing machine 104, and it is possible to eliminate the need to replace the water detection device 100. Furthermore, in the first embodiment, moisture detection can be performed using the entire main flow of the fuel oil 101 transferred by the pump in the weighing machine 104. Therefore, moisture can be detected with high accuracy. As described above, in the first embodiment, it is possible to eliminate the need to replace the water detection device 100 even when replacing the weighing machine 104 while accurately detecting moisture.

  FIG. 7 is a diagram for explaining a fuel supply control method by the water contamination monitoring system in the first embodiment. In FIG. 7, the measurement circuit 56 measures the capacitance C between the piping unit 10 and the electrode 12 at all times or at a predetermined sampling period. A shorter sampling period is desirable. For example, it may be several seconds or about one minute. Alternatively, the capacitance C may be measured immediately before refueling the vehicle 300.

  In the fuel supply control method according to the first embodiment, when the fuel oil 101 stored in the storage tank 102 installed in the fuel filling station is supplied to the vehicle 300 via the measuring device 104 arranged on the ground, the water supply detection method The apparatus 100 is used to detect moisture in the fuel oil 101 supplied from the storage tank 102 to the weighing machine 104. Then, when moisture in the fuel oil 101 is detected, the supply of the fuel oil 101 from the weighing machine 104 to the vehicle 300 is stopped. Specifically, it operates as follows.

  When the vehicle 300 arrives at the gas station, information for requesting oil to the meter 104 is input by an employee or user of the gas station. For example, the type of fuel oil 101, the scheduled amount of fuel supply, and / or the fee payment method, and the like.

  When such information is input to the weighing machine 104, the weighing machine 104 receives a refueling permission application signal from the weighing machine 104 to the weighing machine control circuit 60 together with information such as the type of fuel oil 101, the expected amount of refueling, and / or the payment method. Is output. The measuring machine control circuit 60 outputs a fueling permission application signal to the POS terminal 200 together with information such as the type of fuel oil 101, the scheduled fueling amount, and / or the fee payment method.

  The POS terminal 200 outputs a refueling permission signal to the meter control circuit 60 on the basis of information such as the type of fuel oil 101, the scheduled refueling amount, and / or the fee payment method. The weighing machine control circuit 60 outputs the received refueling permission signal to the weighing machine 104. As a result, the weighing machine 104 is in a state where the vehicle 300 can be refueled. Then, the fuel oil 101 is supplied from the fuel nozzle to the vehicle 300 by an employee or a user of the gas station.

  On the other hand, the measurement result obtained by the measurement circuit 56 is output to the determination circuit 54 every measurement. The determination circuit 54 receives the measurement result of the capacitance C from the measurement circuit 56, and each time it is received, whether or not moisture is mixed in the fuel oil 101 using the measured capacitance value (C> Th?) Is determined.

  When the water detection device 100 detects water in the fuel oil 101 during such refueling, the determination circuit 54 outputs a water detection signal indicating that water has been detected (when C> Th) to the weighing machine control circuit 60. To do.

  The weighing machine control circuit 60 (control circuit) is independent of the control signal from the POS terminal 200 when the determination circuit 54 (determination unit) determines that moisture is mixed in the fuel oil 101 (C> Th). Thus, the meter 104 is controlled so as to stop the fuel supply to the vehicle 300. Specifically, the weighing machine control circuit 60 outputs a refueling stop signal to the weighing machine 104 when receiving the water detection signal. As soon as the meter 104 receives the refueling stop signal, it stops the supply (fueling) of the fuel oil 101 from the meter 104 to the vehicle 300.

  On the other hand, if the water detection device 100 has already detected water (C> Th) before refueling the vehicle 300, the determination circuit 54 sends a water detection signal indicating that moisture has been detected to the weighing machine control circuit 60. Output.

  The weighing machine control circuit 60 outputs a refueling stop signal to the weighing machine 104 when receiving the water detection signal. The weighing machine 104 prohibits the supply (fuel supply) of the fuel oil 101 when receiving the refueling stop signal. In this state, even if information for requesting refueling is input to the measuring device 104 by an employee or a user of the refueling station, the measuring device 104 does not accept refueling. Alternatively, even if a refueling permission signal is output from the POS terminal 200, the refueling permission signal is not relayed to the weighing machine 104. It is also preferable to display a water detection alarm or the like.

  As described above, according to the first embodiment, it is possible to avoid erroneously supplying the fuel oil 101 mixed with moisture to the vehicle 300. In the first embodiment, since the weighing machine control circuit 60 that relays communication between the weighing machine 104 and the POS terminal 200 is arranged, the signal from the water detection device 100 is fed back to the POS terminal 200. There is no need to let them. In other words, it is possible to eliminate the need to improve the existing POS terminal in order to correspond to the signal from the water detection device 100.

Furthermore, in Embodiment 1, since the piping unit 10 and the electrode 12 of the water detection device 100 are disposed in the piping connection pit 113, the measuring device 104 can be installed regardless of the manufacturer (manufacturer). Further, as compared with the case where the water detection device 100 is disposed in the weighing machine 104, the water detection position can be farther from the fueling nozzle of the weighing machine 104. Therefore, it is possible to cope with moisture contamination by an easy mechanism without taking urgent countermeasures.
In the present embodiment, the weighing machine control circuit 60 is described as being independent of the POS terminal 200, but there is no problem even if the weighing machine control circuit 60 is incorporated in the POS terminal 200. In such a case, by transmitting the determination result to the POS terminal 200, it is possible to smoothly handle the processing for the customer related to the control of the weighing machine 104.

Embodiment 2. FIG.
FIG. 8 is a diagram illustrating an example of a configuration of a water detection device arranged in a pipe connection pit in the second embodiment. In FIG. 8, in the second embodiment, a flow sensor 34 is further arranged on the suction side (underground tank side) or the discharge side (measuring machine 104 side) of the piping unit 10 of the water detection device 100. Other configurations are the same as those in FIG. The contents other than those described in particular are the same as those in the first embodiment.

  The flow rate sensor 34 measures the flow rate (flow velocity V) per unit time of the fuel oil 101 flowing in the piping unit 10. The measured result is output to the determination circuit 54. The determination circuit 54 changes the threshold value Th of the capacitance for determining that water is mixed in the fuel oil 101 according to the measured flow velocity V. As the flow velocity V increases, the centrifugal force also increases, so that the separation of the moisture layer further proceeds. Therefore, the water detection sensitivity is further increased. Therefore, even if the threshold value is tightened, even a small amount of water can be detected, and the risk of erroneous detection due to an external factor can be reduced. In addition, as shown in FIG. 9, if a plurality of electrodes are provided, it is possible to switch which electrode performs water detection determination according to the flow rate measured by the flow rate sensor 34, or the weight for each electrode (the multiplication factor on the capacitance value). It is also possible to judge by multiplying.

The embodiments have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. The length of each piping material which comprises the piping unit 10, a routing order, etc. are not limited to the example of FIG.
In the present invention, a capacitance sensor is used in the water detection device, but other sensors can also be used. For example, a simple continuity sensor that detects continuity when mixed with water, a specific gravity sensor that detects the difference in the specific gravity of oil and water, an ultrasonic sensor that detects the difference in the reflection of ultrasonic waves between oil and water, or water in the oil It can be replaced with an optical sensor or the like for detecting the cloudiness when mixed.

  In addition, although descriptions are omitted for parts and the like that are not directly required for the description of the present invention, such as a device configuration and a control method, a required device configuration and a control method can be appropriately selected and used.

  In addition, all water detection devices, fuel supply control methods, and water contamination monitoring systems that include elements of the present invention and that can be appropriately modified by those skilled in the art are included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 10 Piping unit 12 Electrode 14 Wiring 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 Piping part 31, 32 Flange 34 Flow rate sensor 50 Control panel 54 Judgment circuit 56 Measuring circuit 60 Weighing machine control Circuit 100 Water detector 101 Fuel oil 102 Storage tank 103 Base 104 Weighing machine 106 Tank trucks 112, 114, 115 Pipe 113 Pipe connection pit 116 Pipe inlet 200 POS terminal 300 Vehicle 500 Water contamination monitoring system

Claims (6)

A conductive material having a horizontal piping part that forms part of a flow path for sending the fuel to a measuring machine that supplies fuel to a vehicle from an underground tank in which fuel is stored in a fuel filling station and that forms the flow path in a horizontal direction A piping unit using
Arranged at a position in the horizontal flow path in the horizontal pipe section on the upstream side of the position where the flow path changes direction from the horizontal direction and at a position lower than the center height position of the horizontal pipe section Electrodes,
A measurement unit for measuring a capacitance between the electrode and the piping unit;
A determination unit that determines whether moisture is mixed in the fuel using a measured capacitance value;
With
The pipe unit and the electrode are arranged in a pipe connection pit under the weighing machine and at least partially buried underground ,
The piping unit further includes a circumferential piping section that forms a flow path for sending the fuel along a circumferential direction from a position higher than the horizontal flow path toward the horizontal flow path. A water detection device. The connection port underground tank side connection port of the pipe unit and the weighing machine side, the water sensing apparatus according to claim 1, characterized in that it is formed substantially coaxially in one direction. 3. The determination unit according to claim 1, wherein the determination unit determines that a water pool is generated in the pipe unit when the capacitance is not measurable as a result of the measurement. The water detector described. A sensor for measuring a flow rate of the fuel flowing in the piping unit;
Water detection device according to any one of claims 1 to 3, characterized in that changing the threshold value of capacitance for determining the water mixed in the fuel in response to the measured flow rate. In a fuel supply control method in the case of supplying fuel stored in an underground tank installed in a fuel filling station to a vehicle via a measuring machine arranged on the ground,
Detecting water in the fuel supplied from the underground tank to the meter using the water detector according to claim 1;
Stopping water supply from the weighing machine to the vehicle when moisture in the fuel is detected;
A fuel supply control method comprising: An electrode disposed in a horizontal flow path of the fuel supplied to the meter, in a pipe connection pit under the meter at the fuel filling station and at least partially buried underground;
Piping constituting the horizontal flow path;
A measuring unit for measuring a capacitance between the electrode and the pipe;
A determination unit that determines whether moisture is mixed in the fuel using a measured capacitance value;
Independently of the control from the POS terminal, when the POS terminal for controlling the weighing machine is connected to the weighing machine so as to be able to be relayed and the determination unit determines that moisture is mixed in the fuel, A control unit for controlling the weighing machine to stop the supply of fuel to the vehicle;
Equipped with a,
The electrode is disposed at a position in the horizontal flow path on the upstream side of the position where the flow path changes direction from the horizontal direction,
The water mixing monitoring system , wherein the pipe further forms a flow path for sending the fuel along a circumferential direction from a position higher than the horizontal flow path toward the horizontal flow path .