Gas supply device, and method for controlling the same

【0001】

[Technical field to which the invention belongs]

The present invention relates to a gas supply device, and more particularly to a gas supply device configured to obtain the remaining amount of gas in the filling hose according to the pressure difference remaining in the filling hose.

【0002】

[Conventional technology]

For example, a gas supply device that supplies compressed natural gas (CNG) obtained by compressing natural gas to another tank includes, for example, a compressor, a gas storage unit, and a dispenser unit, and the dispenser unit is a flow meter. , A control valve, and a pressure sensor (see, for example, Patent Document 1).

【0003】

In this gas supply device, gas boosted to a predetermined pressure or higher (for example, 25 MPa) by a compressor is stored in a gas supply tank as a supply source. Then, when the automobile to be supplied with fuel arrives, the filling coupling provided at the tip of the filling hose is coupled to the connection portion (coupler) of the fuel tank (filled tank) of the automobile. The connection portion on the automobile side has a built-in check valve, and when the filling coupling is coupled and the pressure on the filling hose side is larger than the pressure of the fuel tank, the check valve opens due to the pressure difference.

【0004】

After that, the three-way valve of the filling coupling is switched and the gas stored in the gas supply tank is filled into the fuel tank of the automobile via the filling hose and the filling coupling. At this time, gas remains in the fuel tank of the automobile, but since the pressure (supply pressure) of the gas supply tank is sufficiently larger than the pressure of the fuel tank, gas filling is performed by the pressure difference.

【0005】

Then, the gas stored in the gas supply tank is supplied to the fuel tank of the automobile and filled until the inside of the fuel tank reaches a predetermined full tank pressure (for example, 20 MPa), and the gas is filled by switching the three-way valve of the filling coupling. Is finished.

【0006】

When the gas filling is completed, the operator separates the filling coupling from the coupler on the automobile side and stores the filling coupling in the coupling storage portion.

【0007】

In addition, the amount of gas supplied to the fuel tank of an automobile is measured by a flow meter, and the total flow rate filled in the fuel tank can be known, and the pressure filled in the fuel tank is a pressure sensor (pressure measuring means). Can be measured by. Further, the tip of the filling hose is provided with a filling coupling connected to the connection portion of the fuel tank, and this filling coupling is connected to the fuel tank of the automobile before the gas is supplied, and the fuel tank is connected after the gas filling is completed. Is removed from.

【0008】

However, when the pressure inside the filling hose is high, the filling coupling cannot be disconnected from the connection portion of the fuel tank. Therefore, the operator switches the manual three-way valve to release the gas in the filling coupling to the atmosphere, or collects the gas in the filling coupling to the drain tank to reduce the pressure in the filling hose to atmospheric pressure. By performing the depressurization operation of the filling coupling in this way, the filling coupling can be disconnected from the connection portion of the fuel tank.

【0009】

[Patent Document 1]

Japanese Unexamined Patent Publication No. 8-68496 [0010]

[Problems to be Solved by the Invention]

In the gas supply device having the above configuration, when filling the fuel tanks of two automobiles in succession, the full tank pressure is determined by the pressure resistance reference value of the fuel tanks, so the previous filling remaining in the filling hose Since the end pressure and the filling end pressure this time are almost the same, no error occurs.

【0011】

However, when the first vehicle is preset-filled at an arbitrary predetermined pressure and then the second vehicle is fully filled, the previous filling end pressure remaining in the filling hose and the current filling end pressure are the same. Therefore, an error occurs.

【0012】

Further, in the gas supply device, since the flow meter is located upstream of the control valve, when the filling coupling is connected to the connection part of the automobile with the control valve closed, the gas remaining in the filling hose is filled coupling. It is not possible to measure the amount of gas supplied to the fuel tank of an automobile via.

【0013】

On the other hand, the flow meter can measure the amount of gas supplied from the start of filling this time (opening of the on-off valve and control valve) to the end of this filling (closing of the on-off valve and control valve). is there. Further, what can be detected by the pressure sensor is the pressure value downstream from the control valve and the pressure of the filling hose.

【0014】

Therefore, in the gas supply device, it is not possible to measure with a flow meter how much gas remaining in the filling hose is supplied to the automobile side by connecting the filling coupling before the filling is started, and the gas supply is accurate. Since the amount is unknown, there is a problem that a flow rate error occurs due to the pressure difference between the residual pressure of the hose before the start of filling and the residual pressure of the hose after the completion of filling.

【0015】

If the residual pressure of the hose after the completion of filling is higher than the gas pressure remaining in the filling hose before the start of filling (before the connection of the filling coupling), the gas having this pressure difference will be released. Although it is measured by a flow meter, it is not supplied to the automobile side, and there is a problem that a flow error occurs.

【0016】

Also, if you forget to open the valve of the filling coupling, or if you start supplying gas even though the filling coupling is not coupled to the coupler on the automobile side, the pressure inside the filling hose will be the supply pressure. There is a possibility that the load on the filling hose will increase. Therefore, an object of the present invention is to provide a gas supply device that solves the above problems.

【0017】

[Means for solving problems]

In order to solve the above problems, the present invention has the following features. The invention according to claim 1 is a coupling storage portion in which the filling coupling is stored when the filling coupling is not used, a detection means for detecting that the filling coupling is removed from the coupling storage portion, and a detection means. The filling start instruction switch operated when supplying gas from the filling coupling and the pressure value measured by the pressure measuring unit when the detection means detects that the filling coupling has been removed are stored as the initial pressure value. Initial pressure value storage means to store, filling start pressure value storage means to store the pressure value measured by the pressure measuring unit when the filling start instruction switch is operated as the filling start pressure value, initial pressure value and filling start pressure. It is equipped with a differential pressure calculation means for calculating the difference from the value, and there is a pressure difference between the initial pressure and the filling start pressure when the filling coupling is removed from the coupling storage section and connected to the tank to be filled. It is also possible to correct the flow error of the pressure remaining in the path downstream of the flow meter.

【0018】

The invention of claim 2, wherein the differential pressure calculating means further calculating differential pressure is intended to open the closing valve when the predetermined value or more, the filling coupling is properly connected to the filling side, Moreover, when the valve of the filling coupling is opened, the gas supply is started, and when the filling coupling is not connected to the side to be filled or the valve of the filling coupling is not opened, the valve of the filling coupling is not opened. Safety is improved by stopping the gas supply and not applying excessive pressure to the filling hose.

【0019】

The invention according to claim 3 stores the pressure value measured by the pressure measuring unit as an initial pressure value when the coupling detecting means detects that the filling coupling has been removed from the accommodating portion. Calculate the difference between the initial pressure value and the filling start pressure value in step 1 and the second step in which the pressure value measured by the pressure measuring unit when the indicating means is operated is stored as the filling start pressure value. The third step is to have the computer execute, and even if there is a pressure difference between the initial pressure and the filling start pressure with the filling coupling removed from the coupling housing and connected to the tank to be filled, the flow meter It is possible to correct the flow error of the pressure remaining in the downstream path.

【0020】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram showing a system configuration of the gas supply device according to the present invention. In FIG. 1, the gas supply device 10 is installed, for example, at a gas supply station that supplies compressed natural gas (CNG) obtained by compressing city gas to a predetermined pressure to a fuel tank (filled container) 14 of an automobile 12. The compressed natural gas is an example, and the gas handled by the gas supply device 10 is not limited to this, and includes other gases that are compressed and used in a high pressure range of about 20 MPa from atmospheric pressure.

【0021】

The gas supply device 10 is roughly composed of a pressure generating unit 16 for boosting city gas to a predetermined pressure and a dispenser unit 18 for supplying the gas compressed by the pressure generating unit 16 to the fuel tank 14.

【0022】

The pressure generating unit 16 has a multi-stage compressor that compresses city gas supplied through a medium pressure pipeline (not shown) fed at medium pressure (pressure higher than the pressure used at home). .. In this embodiment, when the maximum pressure of the fuel tank 14 is 20 MPa, the pressure generating unit 16 pressurizes the pressure to 25 MPa.

【0023】

Further, a gas supply line 20 of the dispenser unit 18 is connected to the discharge port of the pressure generation unit 16, and a flow meter 22 that measures the amount of gas supplied to the fuel tank 14 is connected to the gas supply line 20. The on-off valve 24 that opens and closes the gas supply pipeline 20, the control valve 26 that controls the gas pressure and flow rate supplied to the fuel tank 14 to predetermined values, and the supply gas pressure supplied to the fuel tank 14 are measured. A pressure sensor (pressure measuring unit) 28 is provided.

【0024】

A coupling hook (storage unit) 30 is provided on the side surface of the dispenser unit 18, and a coupling switch (coupling detection means) 32 is provided on the coupling hook 30. Further, the dispenser unit 18 is provided with a filling start switch (instruction means) 34 and a filling stop switch 36.

【0025】

Further, the dispenser unit 18 has a control circuit 38 electrically connected to the flow meter 22, an on-off valve 24, a control valve 26, a pressure sensor 28, a coupling switch 32, a filling start switch 34, and a filling stop switch 36. .. The control circuit 38 is composed of a microcomputer or the like, and controls an on-off valve 24 and a control valve 26 as described later.

【0026】

The control circuit 38 receives a flow rate signal from the flow meter 22, a pressure signal from the pressure sensor 28, and a coupling detection signal from the coupling switch 32, and controls the opening or closing of the on-off valve 24. And the valve opening of the control valve 26 is adjusted to control the flow rate and pressure.

【0027】

In the memory 39 of the control circuit 38, a control program (differential pressure calculation means) for obtaining the pressure difference between the gas filling start pressure value measured by the pressure sensor 28 and the initial value, and a filling cup from the flow meter 22 to this pressure difference. A control program (filling amount correction calculation means) that calculates the filling amount correction value by multiplying the volume in the gas supply path to the ring 42 (the volume of the gas supply line 20 and the filling hose 40 downstream from the flow meter 22). Is stored. Further, the control circuit 38 can correct the flow rate error due to the difference in the residual pressure of the filling hose 40 by subtracting the calculated correction amount from the total filling amount.

【0028】

One end of the filling hose 40 drawn from the side surface of the dispenser unit 18 is connected to the gas supply pipe line 20, and the filling coupling 42 is communicated with the other end. The filling coupling 42 includes a manual three-way valve 44 manually operated by an operator and a coupling 48 coupled to the coupling 46 of the fuel tank 14.

【0029】

The manual three-way valve 44 has a handle 44a for manual operation, an a port on the gas supply side, a b port on the gas discharge side, and a c port on the decompression side. A filling hose 40 is communicated with the a port of the manual three-way valve 42, and a coupling 48 is provided with the b port. Further, the c port of the manual three-way valve 42 is an exhaust port for discharging the residual pressure of the coupling 48 to the outside (atmosphere or recovery path) after the completion of filling.

【0030】

Further, a check valve 52 is provided in the pipeline 50 that communicates the fuel tank 14 and the coupling 46 so that the gas filled in the fuel tank 14 does not flow back to the filling coupling 42. A manual on-off valve may be provided instead of the check valve 52.

【0031】

FIG. 2 is a graph showing an example of pressure change and flow rate change from the start of gas filling to the end of gas filling. In FIG. 2, graph I shows the change in pressure measured by the pressure sensor 28, and graph II shows the change in flow rate measured by the flow meter 22. As shown in Graph I of FIG. 2, P1 is the pre-filling pressure, P2 is the filling start pressure, P3 is the constant flow control end pressure at the start of filling, P4 is the constant pressure rise control end pressure, and P5 is the end of filling. It is the constant flow rate control end pressure.

【0032】

Graph I is the pressure measured by the pressure sensor 28 and shows the pressure filled in the fuel tank 14, that is, the pressure change of the gas supply line 20 and the filling hose 40. Then, when the coupling 48 is coupled to the coupling 46 of the fuel tank 14 and the a and b ports of the manual three-way valve 44 are communicated with each other, the gas remaining in the filling hose 40 is supplied to the fuel tank 14. As a result, the pressure in the filling hose 40 drops from the pre-filling pressure P1 to the current filling start pressure P2.

【0033】

The pressure change ΔP (= P1-P2) before the start of filling at this time varies depending on the pressure P1 before the start of filling and the residual pressure and volume of the fuel tank 14. The pre-filling pressure P1 is not a constant value when the previous filling is preset filling, so it becomes a different value each time. Further, the residual pressure of the fuel tank 14 is filled at the discretion of the driver, so that the residual pressure is different each time.

【0034】

Therefore, the pressure change ΔP will fluctuate except when the tank is fully filled each time. However, since this pressure change ΔP is the pressure change before the start of filling when the on-off valve 24 is closed, the flow rate of the gas supplied from the filling hose 40 to the fuel tank 14 cannot be measured by the flow meter 22. ..

【0035】

The pressure change ΔP'(= P4-P3) after the completion of filling is the pressure increase due to the filling downstream of the control valve 26, and the filling amount into the fuel tank 14 and the filling amount to the filling hose 40 at the same time. including. When the pressure change after filling is ΔP'(= P4-P3)> 0, the gas supply line 20 and the filling hose 40 downstream of the flow meter 22 are filled as measured by the flow meter 22. The amount does not enter the fuel tank 14, but remains in the gas supply line 20 and the filling hose 40.

【0036】

As shown in Graph II of Fig. 2, Q1 is the flow rate at the start of filling, Q2 is the flow rate at the start of constant pressure rise control, Q3 is the flow rate at the branch point where the flow rate rises, Q4 is the flow rate at the start of throttle, and Q5 is the flow rate at the end of filling. Q6 is the flow rate at the end of filling.

【0037】

In Q1 to Q2 and Q5 to Q6, quantitative control with a low flow rate is performed in order to stably perform the detection accuracy of the pressure sensor 28. In addition, Q2 to Q4 show the flow rate change according to the constant pressure rise control.

【0038】

Here, a method of calculating the correction amount K according to the pressure difference between the filling start pressure and the filling end pressure of the filling hose 40 for the integrated flow rate measured by the flow meter 22 will be described. The correction amount K can be obtained by the following equation (1).

【0039】

K = V × (Pe-Ps) / Pa ... (1) In addition, Pa in Eq. (1) is the atmospheric pressure, and V is formed inside the gas supply line 20 and the filling hose 40 downstream from the flow meter 22. It is the geometric volume of the flow path.

【0040】

Then, when the correction amount K is positive, the accurate filling amount is calculated by subtracting this correction amount from the integrated flow rate measured by the flow meter 22. If the correction amount K is negative, the correction amount is added to the integrated flow rate to correct the filling amount display value.

【0041】

The correction of the filling amount is performed when the constant flow rate control is performed immediately before the end of filling.

【0042】

Here, the condition for switching the filling control from the constant pressure rise control (P3 to P4) to the constant flow rate control (P4 to P5) is that the remaining filling amount or (quantitative set amount-current filling amount) is set to a preset value. When it reaches, the filling end condition is when the full tank pressure (P5) or the quantitative set value (preset value) is reached. The above equation (1) is as follows.

【0043】

K = {V × (P-Pe) / Pa}-{V × (P-Ps) / Pa} ... (2) P in Eq. (2) is a preset set pressure, which is full here. Tan pressure. Therefore, in this equation (2), the calculation of V × (P-Ps) / Pa can be performed immediately after the start of filling. Then, even if the filling hose 40 starts filling from the full pressure and the filling stop switch 36 is turned on to stop the gas supply during filling, it is possible to correct the flow rate error at the start of filling.

【0044】

Further, the internal volume (V) of the filling hose 40 to be set in advance is usually known from the design dimensions, but the accuracy is further improved by obtaining it from the actual filling amount as described below.

【0045】

By reducing the pressure of the filling hose 40 to atmospheric pressure (Pa) and then operating the filling start switch 34, the on-off valve 24 is opened and gas filling is started. At this time, in order to ensure that the coupling 48 of the filling coupling 44 is not coupled to the coupling 46 of the automobile 12, the presence or absence of a signal from the coupling switch 32 is monitored.

【0046】

Then, when the full tank pressure (P5) is reached, the on-off valve 24 is closed to complete filling, and the integrated flow rate measured by the flow meter 22 is stored in the memory 39.

【0047】

{Measured value (volume value) / (full tank pressure / atmospheric pressure)} ... (3) Geometric volume (V) of the gas supply line 20 and the filling hose 40 downstream from the flow meter 22 according to this equation (3). Is calculated and stored in the memory 39. This arithmetic processing is performed by a specific operation such as the geometric volume setting mode.

【0048】

Further, the accuracy of the flow rate correction calculation process is improved by storing the gas compression coefficient data related to the pressure in the database in advance and correcting the compression coefficient according to the pressure at that time in the above equations (1) and (2).

【0049】

Here, the processing procedure of the control processing executed by the control circuit 38 when the geometric volume setting mode is set will be described.

【0050】

FIG. 3 is a flowchart for explaining the filling process executed by the control circuit 38. The geometric volume setting mode is performed at the time of maintenance or replacement of the filling hose 40.

【0051】

When setting the geometric volume setting mode, for example, the operator performing the setting operation allows the a and b ports of the manual three-way valve 44 to be communicated in advance, so that the gas remaining in the filling hose 40 is released to the atmosphere. The pressure of the filling hose 40 is reduced to atmospheric pressure (Pa). Then, the manual operation handle 44a of the manual three-way valve 44 is operated to communicate the b and c ports, and the a port is shut off (valve closed state). In this way, by increasing the pressure of the filling hose 40 to the upper limit pressure (full tank pressure) while the pressure of the filling hose 40 is set to atmospheric pressure (Pa), the above-mentioned flow meter 22 to the filling coupling 42 can be reached. It becomes possible to calculate the geometric volume V accurately.

【0052】

As shown in FIG. 3, the control circuit 38 confirms whether or not the hose internal volume setting mode is set in step S1 (hereinafter, step is omitted). If the geometric volume setting mode is set by the operator's operation in S1, proceed to S2 and check whether the coupling switch 32 is on.

【0053】

When the coupling switch 32 is on, it is determined that the filling coupling 42 is hung on the coupling hook 30, and the process proceeds to S3.

【0054】

In S3, it checks whether the filling start switch 34 is on. In S3, when the filling start switch 34 is operated to be turned on, it proceeds to S4, reads the pressure value measured by the pressure sensor 28, and checks whether the pressure of the filling hose 40 is atmospheric pressure (Pa).

【0055】

In S4, if the pressure value measured by the pressure sensor 28 is not atmospheric pressure (Pa), proceed to S5, display that the pressure of the filling hose 40 is equal to or higher than atmospheric pressure (Pa), and issue an alarm. To notify. In this case, the operator opens and closes the handle 44a for manual operation of the manual three-way valve 44 described above to release the gas remaining in the filling hose 40 into the atmosphere, and the pressure of the filling hose 40 is atmospheric pressure (Pa). To do.

【0056】

Then, the processes of S2 to S4 are performed again. In the above S4, when the pressure value measured by the pressure sensor 28 is atmospheric pressure (Pa), the process proceeds to S6, the on-off valve 24 is opened, and the filling hose 40 is filled with gas.

【0057】

In the next S7, it is checked whether the pressure value measured by the pressure sensor 28 has reached the upper limit pressure (P5). In S7, when the pressure value measured by the pressure sensor 28 reaches the upper limit pressure (P5), the process proceeds to S8, the on-off valve 24 is closed, and the filling hose 40 is stopped from being filled with gas.

【0058】

Then, in S9, the flow rate value measured by the flow meter 22 is read from the atmospheric pressure until the upper limit pressure (P5) is reached. Subsequently, in S10, the geometric volume (V) of the gas supply line 20 and the filling hose 40 downstream from the flow meter 22 is calculated by the above-mentioned equation (3) and stored in the memory 39.

【0059】

In the above description, by increasing the pressure of the filling hose 40 to the upper limit pressure (full tank pressure) while the pressure of the filling hose 40 is set to atmospheric pressure (Pa), the filling coupling 42 from the above-mentioned flow meter 22 The method of accurately calculating the geometric volume V up to is explained, but the starting pressure is not limited to any pressure other than atmospheric pressure (Pa), or the upper limit pressure is any pressure other than full pressure (in this case). , Pressure higher than the starting pressure) can also be set.

【0060】

That is, the volume in the gas supply path from the flow meter 22 to the filling coupling 42 is determined by the pressure sensor 28 when the on-off valve 22 is closed while the filling coupling 42 is kept closed. The pressure difference is calculated from the measured pre-filling pressure value and the post-filling pressure value measured by the pressure sensor 28 when the on-off valve 24 is opened in that state, and the pressure difference and the pre-filling pressure value are calculated. It can be obtained based on the supply amount measured by the flow meter 22 when the pressure is increased to the pressure value after filling.

【0061】

Here, the processing procedure of the filling control process executed by the control circuit 38 will be described. FIG. 4 is a flowchart for explaining the filling process executed by the control circuit 38. As shown in FIG. 4, in S11, when the coupling switch 32 is turned off, it is determined that the filling coupling 42 has been removed from the coupling hook 30. The operator removes the filling coupling 42 from the coupling hook 30 and then couples the coupling 48 to the coupling 46 of the fuel tank 14.

【0062】

Then, the operator rotates the manual operation handle 44a of the manual three-way valve 44 to communicate the a port and the b port. As a result, the gas remaining in the filling hose 40 is supplied to the fuel tank 14 of the automobile 12, and the pressure of the filling hose 40 drops from the pressure P1 before the filling start to the filling start pressure P2 this time.

【0063】

In the next S12, the initial pressure value at the start of filling (pressure in the hose Ps = P1) measured by the pressure sensor 28 is read and stored in the memory 39 (initial pressure value storage means). At this time, in the previous filling process, the pressure value at the start of filling stored in the memory 39 is erased.

【0064】

Then, the process proceeds to S13 to check whether the filling start switch 34 has been turned on. In S13, when the filling start switch 34 is off, the process shifts to S14 to check whether the coupling switch 32 is off. In S14, when the coupling switch 32 is on, it is determined that the filling coupling 42 has been returned to the coupling hook 30, and the process returns to S11.

【0065】

Further, in S14, when the coupling switch 32 is off, the filling coupling 42 is removed from the coupling hook 30, and the process returns to S13. Further, in the above S13, when the filling start switch 34 is on, the process proceeds to S15 to open the on-off valve 24. The high-pressure gas generated by the pressure generating unit 16 is now supplied to the fuel tank 14 via the gas supply line 20, the filling hose 40, and the filling coupling 42.

【0066】

In the next S16, the valve opening degree of the control valve 26 is controlled so that the constant flow rate control is performed from the start of filling until a predetermined time elapses. This constant flow rate control is Q1 to Q2 shown in Graph II of FIG.

【0067】

In the next S17, in the constant flow rate control, it is confirmed whether or not the flow rate value (measured value) measured by the flow meter 22 has reached a preset set amount, and the flow rate measured by the flow meter 22. If the value does not reach the set amount, the process returns to S16 and the valve opening degree of the control valve 26 is controlled so that the flow rate value becomes the set amount.

【0068】

Further, in S17, when the flow rate value (measured value) measured by the flow meter 22 reaches a preset set amount, the process proceeds to S18 and the valve opening of the control valve 26 is adjusted so as to control the constant pressure rise. Control. This constant pressure increase control is P3 to P4 shown in Graph I of FIG.

【0069】

In the next S19, the flow rate value (measured value) measured by the flow meter 22 is the value obtained by subtracting the predetermined set amount (flow rate from the start of drawing to the end of filling) from the quantitative set value (preset value) (the value immediately before the preset value). ) Is equal to. In S19, when the flow rate value measured by the flow meter 22 does not reach the value obtained by subtracting the predetermined set amount from the quantitative set value, the process proceeds to S27 and it is checked whether the filling stop switch 36 is turned on. ..

【0070】

In S27, when the filling stop switch 36 is not turned on, the process returns to S18 and the processes of S18, S19, and S27 are repeated.

【0071】

Further, in S19, when the flow rate value measured by the flow meter 22 reaches the value obtained by subtracting the predetermined set amount from the quantitative set value, the process proceeds to S20 and the control valve 26 is controlled so as to perform constant flow rate control at the end of filling. Control the valve opening of. This constant flow rate control is Q5 to Q6 shown in Graph II of FIG.

【0072】

Subsequently, the process proceeds to S21, and the pressure (Pe = P4) at the end of filling is read from the pressure sensor 28 and stored in the memory 39. At this time, in the previous filling process, the pressure value at the end of filling stored in the memory 39 is erased.

【0073】

In the next S22, the pressure difference between the filling start pressure Ps and the filling end pressure Pe is multiplied by the geometric volume V to calculate the amount of gas remaining in the filling hose 40 (correction amount K) according to the pressure difference.

【0074】

Subsequently, the process proceeds to S23, and the filling amount is calculated by adding or subtracting the above correction amount to the measured value from the start of filling to the end of filling.

【0075】

In the next S24, it is checked whether or not the pressure value measured by the pressure sensor 28 has reached the preset upper limit pressure (allowable pressure of the fuel tank 14). In S24, when the pressure value measured by the pressure sensor 28 does not reach the preset upper limit pressure, proceed to S25 and check whether the measured value measured by the flow meter 22 and the filling amount are equal to each other. ..

【0076】

In S25, if the measured value measured by the flow meter 22 and the filling amount are not equal, the process returns to S24 and whether the pressure value measured by the pressure sensor 28 has reached the preset upper limit pressure. Check.

【0077】

Then, in S24, when the pressure value measured by the pressure sensor 28 reaches a preset upper limit pressure, the process proceeds to S26 to close the on-off valve 24. This completes the gas filling process for the fuel tank 14.

【0078】

Further, in the above S27, when the filling stop switch 36 is off, it is determined that the operator has interrupted the gas filling, the process proceeds to S28, and the on-off valve 24 is closed. Subsequently, the process proceeds to S29, and the pressure (Pe = P4) at the end of filling is read from the pressure sensor 28 and stored in the memory 39. At this time, in the previous filling process, the pressure value at the end of filling stored in the memory 39 is erased.

【0079】

Then, in S30, the amount of gas (correction amount K) remaining in the gas supply line 20 and the filling hose 40 downstream of the flow meter 22 is calculated according to the pressure difference between the filling start pressure Ps and the filling end pressure Pe. Subsequently, the process proceeds to S31, and the filling amount obtained by adding or subtracting the above correction amount to the measured value from the start of filling to the end of filling is calculated.

【0080】

In this way, the difference in the amount of gas remaining in the gas supply pipeline 20 and the filling hose 40 downstream from the flow meter 22 before the start of filling and after the end of filling is calculated, and this value is used as the correction amount K and measured by the flow meter 22. By subtracting from the total flow value (added when K is negative), an error due to the difference in the amount of gas remaining in the gas supply line 20 and the filling hose 40 downstream from the flow meter 22 is eliminated. Even when preset filling in which the residual pressures of the gas supply line 20 and the filling hose 40 downstream from 22 are different each time, more accurate filling becomes possible as in the case of continuous full filling.

【0081】

Here, the modification 1 will be described. FIG. 5 is a flowchart for explaining a modification 1 of the filling process executed by the control device 16. In FIG. 5, the processing of S41 to S44 is the same as that of S11 to S14 of FIG. 4 described above, and thus the description thereof will be omitted.

【0082】

In S45, the pressure at the start of filling (Ps1 = P2) is read from the pressure sensor 28 and stored in the memory 39 (filling start pressure value storage means, second step). At this time, in the previous filling process, the pressure value at the start of filling stored in the memory 39 is erased.

【0083】

In the next S46, it is checked whether the pressure value obtained by subtracting the pressure (Ps1 = P2) from the pressure Ps = P1 at the start of filling is larger than the preset predetermined pressure difference. In S46, when the pressure value obtained by subtracting the pressure (Ps1 = P2) from the pressure Ps = P1 at the start of filling is smaller than the preset predetermined pressure difference, the pressure (Ps1 = P2) does not decrease. Therefore, it is judged that the a port and the b port of the manual three-way valve 44 are not communicated, and the process proceeds to S47.

【0084】

The S47 emits an alarm sound (alarm sound) to warn that the filling preparation is not completed. Then, the process proceeds to S48 to check whether the filling start switch 34 has been turned on. In S48, if the filling start switch 34 is not turned on, the process proceeds to S49 and it is checked whether the coupling switch 32 is turned on.

【0085】

In S49, when the coupling switch 32 is switched on, it is determined that the filling coupling 42 has been returned to the coupling hook 30, the process proceeds to S50, and the alarm sound (alarm sound) for which filling preparation is not completed is stopped. Let me. Therefore, since the manual three-way valve 44 of the filling coupling 42 is being operated correctly, the filling process this time is completed.

【0086】

Further, in S48, when the filling start switch 34 is on, in order to start filling, the process proceeds to S51, the alarm sound (alarm sound) for which filling preparation is not completed is stopped, and the process returns to S45.

【0087】

Further, in S49, when the coupling switch 32 is off, the filling coupling 42 has not been returned to the coupling hook 30, so the process returns to S47 and the processing after S47 is repeated.

【0088】

In FIG. 5, the processes of S52 to S68 are the same as the processes of S15 to S31 of FIG. 4 described above, and thus the description thereof will be omitted.

【0089】

In this way, by calculating the difference between the initial pressure value Ps before the start of filling and the amount of gas remaining in the filling hose 40 at the filling start pressure value Ps1, the total measured by the flow meter 22 with this value as the correction amount K is calculated. By subtracting from the flow rate value (adding when K is negative), it is possible to eliminate the error due to the difference in the amount of gas remaining in the gas supply line 20 and the filling hose 40 downstream of the flow meter 22. Therefore, even when preset filling in which the residual pressures of the gas supply pipe 20 and the filling hose 40 downstream of the flow meter 22 are different each time, more accurate filling becomes possible as in the case of continuous full tank filling.

【0090】

In the above embodiment, the case of supplying compressed natural gas (CNG) obtained by compressing city gas is given as an example, but the present invention is not limited to this, and it can also be applied to supply gas such as butane and propane. Of course.

【0091】

Further, in the above embodiment, the case where the fuel tank 14 of the automobile 12 is filled with the compressed gas is given as an example, but the present invention is not limited to this, and the present invention is also applied to a device for supplying the compressed gas to another container or the like. Of course, it can also be applied to devices configured to be installed in the middle of the pipeline to feed the compressed gas to other places.

【0092】

[Effect of the invention]

As described above, according to the invention of claim 1, it is detected that the filling coupling is removed from the coupling storage portion and the coupling storage portion in which the filling coupling is stored when the filling coupling is not used. The detection means to be used, the filling start instruction switch operated when supplying gas from the filling coupling, and the pressure value measured by the pressure measuring unit when the detection means detects that the filling coupling has been removed. An initial pressure value storage means that stores as an initial pressure value, a filling start pressure value storage means that stores the pressure value measured by the pressure measuring unit when the filling start instruction switch is operated as a filling start pressure value, and an initial pressure. Since it is equipped with a differential pressure calculation means for calculating the difference between the value and the filling start pressure value, the pressure between the initial pressure and the filling start pressure is provided with the filling coupling removed from the coupling housing and connected to the tank to be filled. Even if there is a difference, it is possible to correct the flow error of the pressure remaining in the path downstream of the flow meter.

【0093】

Further, according to the invention of claim 2, since the on-off valve is opened when the differential pressure calculated by the differential pressure calculation means is equal to or more than a predetermined value, the filling coupling is correctly connected to the filled side and the filling coupling is correctly connected. The gas supply is started when the valve of the filling coupling is opened, and the gas is supplied when the filling coupling is not connected to the side to be filled or the valve of the filling coupling is not opened. It is possible to improve the safety by stopping the supply of the hose and not applying excessive pressure to the filling hose.

【0094】

Further, according to the invention of claim 3, when it is detected by the coupling detecting means that the filling coupling is removed from the accommodating portion, the pressure value measured by the pressure measuring unit is stored as the initial pressure value. The difference between the initial pressure value and the filling start pressure value is the difference between the first step and the second step of storing the pressure value measured by the pressure measuring unit when the indicating means is operated as the filling start pressure value. In order to let the computer execute the third step of calculation, even if there is a pressure difference between the initial pressure and the filling start pressure with the filling coupling removed from the coupling housing and connected to the tank to be filled, the flow meter It is possible to correct the flow error of the pressure remaining in the downstream path.

[Simple explanation of drawings]

FIG. 1 is a configuration diagram showing a system configuration of a gas supply device according to the present invention.

FIG. 2 is a graph showing an example of pressure change and flow rate change from the start of gas filling to the end of gas filling.

FIG. 3 is a flowchart for explaining a geometric volume setting mode process executed by the control circuit 38.

FIG. 4 is a flowchart for explaining a filling process executed by the control circuit 38.

FIG. 5 is a flowchart for explaining a modification 1 of a filling process executed by the control circuit 38.

[Explanation of symbols]

Ten Gas supply device 12 Automobile 14 Fuel tank 16 Pressure generation unit 18 Dispenser unit 20 Gas supply pipeline 22 Flow meter 24 On-off valve 26 Control valve 28 Pressure sensor 30 Coupling hook 32 Coupling switch 34 Filling start switch 36 Filling stop switch 38 Control Circuit 39 Memory 40 Fill hose 42 Fill coupling 44 Manual three-way valve 46 Coupler 48 Coupling 52 Check valve