Gas supply system

Abstract

A gas supply system is provided with: a gas tank having an automatic closing valve; a gas supply pipe connecting the gas tank and a gas consumption device; a seal; and a shutoff valve disposed in the gas supply pipe. A push rod is arranged at the front end of the gas supply pipe, and when the gas tank gets close, the push rod pushes the automatic closing valve open. When the distance between the automatic closing valve and the push rod is equal to or less than a threshold distance, the sealing member seals a connection space including the automatic closing valve and the front end of the gas supply pipe. The controller advances the gas tank until the automatic closing valve is pushed open, then retreats the gas tank until the automatic closing valve is closed while keeping the connection space sealed, and closes the shutoff valve. When the pressure in the gas supply pipe upstream of the shutoff valve is lower than the pressure in the downstream of the shutoff valve, the controller determines that a gas leak has occurred.

Description

Technical Field

[0001] The technology disclosed in this specification relates to a gas supply system for supplying gas from a gas tank to a gas-consuming device. Background Technology

[0002] Japanese Patent Application Publication No. 2024-89965 discloses a gas supply system comprising multiple gas cylinders that supplies gas from the cylinders to a gas-consuming device. In the gas supply system of Japanese Patent Application Publication No. 2024-89965, a gas leak check is performed before replacing the cylinders when the remaining gas level in all cylinders decreases. When the remaining gas level in all cylinders decreases, the system controller closes the on / off valves of all cylinders and stops the gas-consuming device after consuming the gas in the gas supply pipe. Then, after confirming that the gas pressure in the gas supply pipe has not increased, the controller removes the cylinders from the system. If the gas pressure in the gas supply pipe increases, a gas leak will occur from the on / off valves. In this case, when the cylinders are removed from the system, the gas in the cylinders leaks into the surrounding environment. If the gas pressure in the gas supply pipe increases, the controller stops the removal of the cylinders. Summary of the Invention

[0003] In the gas supply system described in Japanese Patent Application Publication No. 2024-89965, the presence or absence of a gas leak is detected by observing whether the gas pressure within the gas supply pipe increases. Therefore, to perform a gas leak check, it is necessary to temporarily stop the gas supply to the gas-consuming equipment. This specification provides a technique for performing gas leak checks without stopping the gas supply to the gas-consuming equipment.

[0004] The gas supply system disclosed in this specification includes a gas tank, a gas supply pipe, an actuator, a seal, a shut-off valve, a first pressure sensor, a second pressure sensor, and a controller. The gas tank has an automatic shut-off valve that opens when a push rod is pushed in and closes when the push rod is pulled out. The gas tank is connected to the gas supply pipe. The gas supply pipe has a push rod at its front end that guides the gas from the gas tank to a gas-consuming device. The actuator causes the gas tank to move forward and backward relative to the gas supply pipe. When the distance between the automatic shut-off valve and the push rod is shorter than a predetermined threshold distance, the seal seals the connection space including the opening of the automatic shut-off valve and the front end of the gas supply pipe. A shut-off valve is located on the gas supply pipe. The first pressure sensor measures the pressure in the gas supply pipe upstream of the shut-off valve. The second pressure sensor measures the pressure in the gas supply pipe downstream of the shut-off valve.

[0005] The controller controls the actuator to advance the gas cylinder until the automatic shut-off valve is opened. Then, while maintaining the seal of the connection space, the gas cylinder is retracted until the automatic shut-off valve is closed, and the shut-off valve is closed. Furthermore, after a predetermined time, if the measurement value of the first pressure sensor is higher than the measurement value of the second pressure sensor, the controller advances the gas cylinder to reopen the automatic shut-off valve and opens the shut-off valve. If the measurement value of the first pressure sensor is lower than the measurement value of the second pressure sensor, a signal indicating a gas leak has been output.

[0006] When the automatic shut-off valve of the gas cylinder is opened, gas supply to the gas-consuming device begins. In the gas supply system disclosed in this specification, with the gas supply pipe downstream of the shut-off valve filled with gas, a gas leak check is performed upstream of the shut-off valve. The gas cylinder is retracted to close the automatic shut-off valve, and during the gas leak check, the controller closes the shut-off valve. The high-pressure gas accumulated in the gas supply pipe downstream of the shut-off valve continues to be supplied to the gas-consuming device. The gas supply system disclosed in this specification can perform gas leak checks without stopping the gas supply to the gas-consuming device.

[0007] In the gas supply system disclosed in this specification, the gas supply pipe can also be divided into multiple branches, each branch equipped with a first pressure sensor and a push rod. Gas tanks are connected to each branch. The actuator is preferably capable of moving the gas tank relative to the push rod within each branch. It is possible to replace one gas tank with another while supplying gas from one gas tank to the gas-consuming device.

[0008] The detailed description of the technology disclosed in this specification and further improvements are described in the following "Detailed Description". Attached Figure Description

[0009] The features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which the same reference numerals denote the same parts, and wherein:

[0010] Figure 1 This is a block diagram of the gas supply system of the first embodiment;

[0011] Figure 2 This is a cross-sectional view (sealed position) of the gas tank and gas supply pipe.

[0012] Figure 3 This is a cross-sectional view of the gas tank and gas supply pipe (valve open position).

[0013] Figure 4 This is a flowchart for gas leak inspection and handling;

[0014] Figure 5This is a block diagram of the gas supply system of the second embodiment;

[0015] Figure 6 This is a flowchart of gas leak inspection and handling (second embodiment). Detailed Implementation

[0016] First Embodiment

[0017] Reference Figures 1 to 4 The gas supply system 2 of the first embodiment is described. Figure 1 This is a block diagram showing the gas supply system 2. In this embodiment, a fuel cell 90 is connected to the gas supply system 2, and the gas supply system 2 supplies hydrogen from the gas tank 10 to the fuel cell 90. The fuel cell 90 is an example of a gas-consuming device that receives gas from the gas supply system 2.

[0018] The gas supply system 2 includes a gas tank 10, a gas supply pipe 30, a push rod 35, an actuator 19, a first pressure sensor 41, a second pressure sensor 42, a shut-off valve 31, a controller 50, and a display device 51.

[0019] In this embodiment, the gas tank 10 is filled with high-pressure hydrogen. The gas tank 10 and the fuel cell 90 are connected via a gas supply pipe 30. The gas supply pipe 30 guides the hydrogen in the gas tank 10 to the fuel cell 90. A shut-off valve 31 and a pressure reducing valve 32 are connected to the gas supply pipe 30. The pressure reducing valve 32 is located downstream of the shut-off valve 31. Here, "downstream" refers to the side of the gas supply pipe 30 closer to the fuel cell 90 (gas consumption device), and "upstream" refers to the side closer to the gas tank 10.

[0020] Pressure reducing valve 32 reduces the pressure of hydrogen supplied from gas tank 10 to a pressure suitable for the operation of fuel cell 90. That is, the pressure of the gas suitable for the operation of fuel cell 90 is lower than the pressure of the gas supplied from gas tank 10.

[0021] The shut-off valve 31 opens and closes according to instructions from the controller 50. More specifically, the shut-off valve 31 is open during operation of the fuel cell 90, but closes according to instructions from the controller 50. For example, the controller 50 closes the shut-off valve 31 in the event of a gas leak at the connection between the gas tank 10 and the gas supply pipe 30 to prevent hydrogen from leaking to the outside from a location downstream of the shut-off valve 31. Additionally, the controller 50 temporarily closes the shut-off valve 31 during a gas leak inspection and handling process described later.

[0022] The first pressure sensor 41 measures the pressure in the gas supply pipe 30 upstream of the shut-off valve 31. If the gas tank 10 is connected to the gas supply pipe 30, the measured value of the first pressure sensor 41 is approximately equal to the internal pressure of the gas tank 10 (the measured value is lower than the internal pressure of the gas tank by the amount of pressure loss of the automatic shut-off valve 20, etc., described later).

[0023] The second pressure sensor 42 measures the pressure in the gas supply pipe 30 downstream of the shut-off valve 31. During the period when gas is supplied from the gas tank 10, the measurement value of the second pressure sensor 42 is approximately equal to the measurement value of the first pressure sensor 41 (the measurement value of the second pressure sensor 42 is lower than the measurement value of the first pressure sensor 41 by the amount of pressure loss from the shut-off valve 31, etc.).

[0024] exist Figure 1 The lower side shows a cross-sectional view of the pipe head 11 of the gas tank 10 and the front end of the gas supply pipe 30. An automatic shut-off valve 20 is provided at the pipe head 11 of the gas tank 10. The automatic shut-off valve 20 includes a sleeve 21, a valve core 22, and a spring 23. The sleeve 21 is installed inside the pipe head 11. The valve core 22 is disposed adjacent to the sleeve 21 inside the tank. The spring 23 presses the valve core 22 against the opening of the sleeve 21 (the opening into the tank) from the inside of the tank. The opposite end of the spring 23 is supported on the inner wall of the tank.

[0025] Under the force of spring 23, valve core 22 is tightly pressed against the opening of sleeve 21. During this period, the automatic closing valve 20 is closed. When valve core 22 is pushed inward from the outside of the tank, the automatic closing valve 20 opens. When the load on valve core 22 is removed, under the force of spring 23, valve core 22 is once again pressed against the opening of sleeve 21, and the automatic closing valve 20 closes.

[0026] A push rod 35 is provided at the front end of the gas supply pipe 30. The push rod 35 is fixed to the front end of the gas supply pipe 30 by a rod support member 36. A hole is provided on the rod support member 36, through which gas can flow from the gas tank 10 into the gas supply pipe 30.

[0027] When the gas canister 10 is installed in the gas supply system 2, the push rod 35 at the front end of the gas supply pipe 30 faces the pipe head 11. The actuator 19 moves the gas canister 10. The actuator 19 moves the gas canister 10 closer to or further away from the gas supply pipe 30. More specifically, the actuator 19 moves the automatic shut-off valve 20 closer to or further away from the front end (i.e., the push rod 35) of the gas supply pipe 30. Figure 1 The cross-sectional view shows the state where the push rod 35 has left the automatic shut-off valve 20.

[0028] Actuator 19 causes the gas canister 10 to move forward or backward relative to the front end of the gas supply pipe 30. Moving the gas canister 10 closer to the gas supply pipe 30 is called "forward movement," and moving the gas canister 10 away from the gas supply pipe 30 is called "reverse movement." The actuator may also be a device that moves the gas supply pipe 30 forward or backward relative to the gas canister 10.

[0029] A seal 12 is disposed on the inner side of the pipe head 11. When the front end (push rod 35) of the gas supply pipe 30 approaches the automatic shut-off valve 20, the outer periphery of the gas supply pipe 30 contacts the seal 12, sealing the space including the opening of the automatic shut-off valve 20 (the opening to the outside of the gas tank 10) and the front end of the gas supply pipe 30. For convenience, the space including the opening of the automatic shut-off valve 20 and the front end of the gas supply pipe 30 is referred to as the connection space S. More precisely, the connection space S refers to the space inside the pipe head 11 that includes the opening of the automatic shut-off valve 20 and the front end of the gas supply pipe 30. Figure 1 In the cross-sectional view, push rod 35 is disengaged from automatic shut-off valve 20, ensuring a gap G between the front end of gas supply pipe 30 and seal 12. In this state, connection space S is not sealed relative to the outside.

[0030] Figure 2 This represents the cross-section when the front end of the gas supply pipe 30 contacts the seal 12. When the distance between the push rod 35 and the automatic shut-off valve 20 reaches L1, the seal 12 contacts the outer periphery of the gas supply pipe 30, and the connection space S is sealed. In other words, when the distance between the push rod 35 and the valve core 22 of the automatic shut-off valve 20 is shorter than L1, the connection space S is isolated from the outside. When the distance between the push rod 35 and the valve core 22 is L1, the automatic shut-off valve 20 remains closed. The distance L1 can be called the threshold distance.

[0031] Figure 2 The imaginary line represents the state where the gas cylinder 10 advances to the point where the valve core 22 contacts the front end of the push rod 35. When the gas cylinder 10 advances further than the imaginary line, the push rod 35 pushes open the automatic closing valve 20. Figure 3 This is a cross-sectional view of the gas tank 10 as it moves forward until the automatic shut-off valve 20 opens. The thick arrow A indicates the flow of gas. During the opening of the automatic shut-off valve 20, hydrogen in the gas tank 10 flows through the connecting space S to the gas supply pipe 30. Because the connecting space S is sealed by the seal 12, hydrogen will not leak to the outside.

[0032] Gas in gas cylinder 10 flows through the open automatic shut-off valve 20 and through the hole in rod support 36 to gas supply pipe 30. For ease of explanation, the position of gas cylinder 10 when the connection space S is sealed but the automatic shut-off valve 20 is closed is called the sealed position, and the position of gas cylinder 10 when the connection space S is sealed but the automatic shut-off valve 20 is open is called the open valve position. Figure 2This is a cross-sectional view of the sealing location. Figure 3 This is a cross-sectional view of the valve in the open position. The sealing position is when the distance between the push rod 35 and the valve core 22 of the automatic shut-off valve 20 is less than L1 and greater than zero. In the open position, the seal 12 is also in contact with the outer periphery of the gas supply pipe 30, and the connection space S remains sealed.

[0033] Controller 50 (reference) Figure 1 Control actuator 19 and check for gas leaks at seal 12. Figure 4 This is a flowchart illustrating the gas leak detection and handling process. When gas tank 10 is installed in gas supply system 2 (actuator 19), controller 50 initiates the gas leak detection and handling process.

[0034] Below, according to Figure 4 The flowchart illustrates the gas leak detection and handling process. The gas leak detection and handling process begins when gas tank 10 is installed in gas supply system 2. Controller 50 moves gas tank 10 to the open valve position (step S12). Automatic shut-off valve 20 opens, and hydrogen in gas tank 10 flows into gas supply pipe 30. Hydrogen is supplied to fuel cell 90 through gas supply pipe 30. Due to the supply of hydrogen, fuel cell 90 becomes operational. Fuel cell 90 can also begin operation.

[0035] Next, the controller 50 moves the gas tank 10 to the sealed position (step S13) and closes the shut-off valve 31 (step S14). Then, the controller 50 waits for a predetermined time (step S15). When the gas tank 10 moves to the sealed position, the automatic shut-off valve 20 closes, but because high-pressure hydrogen is filled in a position downstream of the shut-off valve 31, hydrogen continues to be supplied to the fuel cell 90 for a period of time. That is, the fuel cell 90 can continue to operate.

[0036] After a specified standby time, the controller 50 acquires the measurement values ​​from the first pressure sensor 41 and the second pressure sensor 42, and compares them (steps S16, S17). Figure 4 In this context, the measured value of the first pressure sensor 41 is recorded as the "first measured value", and the measured value of the second pressure sensor 42 is recorded as the "second measured value".

[0037] In step S16, the first measured value (the measured value of the first pressure sensor 41) represents the pressure in the connection space S. The second measured value (the measured value of the second pressure sensor 42) represents the pressure in the gas supply pipe 30 downstream of the shut-off valve 31. If there is no gas leakage from the connection space S, the first measured value is maintained. If there is gas leakage from the connection space S, the first measured value continuously decreases during a predetermined period of time.

[0038] If the first measured value is equal to or higher than the second measured value, the controller 50 moves the gas tank 10 back to the open valve position (step S17: Yes, S18). Furthermore, the controller 50 opens the shut-off valve 31 (step S19). If, even after a predetermined time, the first measured value is still higher than the second measured value, it can be determined that no gas leakage has occurred from the connection space S sealed by the seal 12. In this case, the controller 50 moves the gas tank 10 back to the open valve position, opens the automatic shut-off valve 20, and opens the shut-off valve 31, continuing to supply gas from the gas tank 10 to the fuel cell 90.

[0039] If the first measured value is lower than the second measured value, the controller 50 outputs a sealing abnormality signal to the display device 51, stopping the gas supply system 2 and the fuel cell 90 (step S17: No, S20, S21). The sealing abnormality signal indicates that a gas leak has occurred at the seal 12. Upon receiving the sealing abnormality signal, the display device 51 illuminates a warning light indicating a gas leak at the seal 12 (or the display device 51 emits a warning sound).

[0040] If, after a predetermined time, the first measured value is lower than the second measured value, it can be determined that the gas in the connection space S is leaking to the outside through the seal 12. That is, it can be determined that a sealing abnormality has occurred. In this case, the controller 50 outputs a sealing abnormality signal indicating that a gas leak has occurred at the seal 12. At this time, the controller 50 keeps the gas tank 10 in the sealed position. In the sealed position, the automatic shut-off valve 20 is closed, so the gas in the connection space S will not leak to the outside. In addition, since the shut-off valve 31 of the gas supply pipe 30 is closed, the gas filling the gas supply pipe 30 downstream of the shut-off valve 31 will not leak into the connection space S.

[0041] As explained above, the gas supply system 2 can perform gas leak checks on the seal 12 without stopping the gas supply to the fuel cell 90 (gas consumption device).

[0042] Further explanation is given regarding actuator 19. In the gas supply system 2 of this embodiment, actuator 19 moves the gas tank 10 (automatic shut-off valve 20) closer to or further away from the gas supply pipe 30 (push rod 35). The actuator can also be any device that moves the gas supply pipe 30 (push rod 35) closer to or further away from the automatic shut-off valve 20. That is, the actuator can simply be any device that moves the gas tank 10 relative to the gas supply pipe 30 forward or backward.

[0043] In the gas supply system 2 of this embodiment, after the gas canister 10 is installed, the controller 50 performs the following process as a gas leak check. Furthermore, the shut-off valve 31 is opened before the gas leak check. (1) The controller 50 controls the actuator 19 to advance the gas canister 10 until the automatic shut-off valve 20 is pushed open. Then, while maintaining the seal of the connection space S, the controller 50 retracts the gas canister 10 to the closed position of the automatic shut-off valve 20 and closes the shut-off valve 31. In other words, the controller 50 controls the actuator 19 to bring the gas canister 10 relatively close to the gas supply pipe 30 until the automatic shut-off valve 20 is pushed open. Then, while maintaining the seal of the connection space S, the controller 50 moves the gas canister 10 relatively away from the gas supply pipe 30 to the closed position of the automatic shut-off valve 20. At the same time, the controller 50 closes the shut-off valve 31.

[0044] (2) After a predetermined time, if the measurement value of the first pressure sensor 41 is higher than the measurement value of the second pressure sensor 42, the controller 50 moves the gas tank 10 forward to reopen the automatic shut-off valve 20 and opens the shut-off valve 31. In other words, after a predetermined time, if the measurement value of the first pressure sensor 41 is higher than the measurement value of the second pressure sensor 42, the controller 50 moves the gas tank 10 relative to the gas supply pipe to reopen the automatic shut-off valve 20. At the same time, the controller 50 opens the shut-off valve 31. On the other hand, if the measurement value of the first pressure sensor 41 is lower than the measurement value of the second pressure sensor 42, the controller 50 outputs a sealing abnormality signal indicating that a gas leak has occurred.

[0045] In this embodiment, a sealing failure signal is sent to the display device 51. Upon receiving the sealing failure signal, the display device 51 outputs a notification (message, warning light, warning sound, etc.) indicating that a gas leak has occurred at the seal 12.

[0046] Second Embodiment

[0047] Reference Figure 5 , 6 The gas supply system 2a of the second embodiment is described. Figure 5 This is a block diagram showing the gas supply system 2a. The gas supply system 2a includes two gas tanks 10a and 10b. The two gas tanks 10a and 10b each have the same structure as the gas tank 10 of the gas supply system 2 in the first embodiment, and have... Figures 2-4 The structure of the two gas tanks 10a and 10b is as follows: each tank is equipped with an automatic shut-off valve 20 and a pipe head 11 including a seal 12.

[0048] The gas supply pipe 30 of the gas supply system 2a branches into multiple branch lines 30a and 30b midway. A first pressure sensor 41a is installed in branch line 30a, and a first pressure sensor 41b is installed in branch line 30b. Furthermore, branch lines 30a and 30b are part of the gas supply pipe 30. A shut-off valve 31 is located downstream of the branch point of the gas supply pipe 30. The first pressure sensors 41a (41b) are located upstream of the shut-off valve 31 to measure the pressure in branch lines 30a and 30b.

[0049] Gas canisters 10a (10b) are disposed on actuators 19a (19b). Actuators 19a and 19b are also the same as actuator 19 in the first embodiment.

[0050] Gas tank 10a is connected to a branch line 30a of the gas supply pipe 30, and gas tank 10b is connected to the branch line 30b. In the gas supply system 2a, hydrogen is alternately supplied to the fuel cell 90 from the two gas tanks 10a and 10b through the gas supply pipe 30. That is, when the gas remaining amount in one gas tank 10a falls below a predetermined lower limit, the gas supply system 2a stops supplying gas from gas tank 10a and supplies gas to the fuel cell 90 from the other gas tank 10b. During the period when hydrogen is supplied from gas tank 10b to the fuel cell 90, gas tank 10a can be replaced with a new gas tank. Then, when the gas remaining amount in gas tank 10b falls below the predetermined lower limit, the gas supply from gas tank 10b stops, and gas is supplied to the fuel cell 90 from the other gas tank 10a. During the period when hydrogen is supplied from gas tank 10a to the fuel cell 90, gas tank 10b can be replaced with a new gas tank.

[0051] Gas supply system 2a performs a gas leak check before replacing the gas tank. Figure 6 This is a flowchart illustrating the gas leak check process performed by the controller of gas supply system 2a.

[0052] according to Figure 6 The flowchart illustrates the gas leak detection in the gas supply system 2a of the second embodiment. Furthermore, in... Figure 6 In the example, gas cylinder 10a is referred to as the first gas cylinder, and gas cylinder 10b is referred to as the second gas cylinder. Figure 6 In the example, during the supply of hydrogen from the first gas tank 10a to the fuel cell 90, the second gas tank 10b is replaced. Figure 6 Gas leak inspection and handling begins when the new second gas tank 10b is set to actuator 19b.

[0053] The controller 50 moves the second gas tank 10b to the sealed position (step S22). In the sealed position, the connection space S of the second gas tank 10b is sealed, but the automatic shut-off valve 20 remains closed.

[0054] The controller 50 remains in standby mode until the pressure of the first gas tank 10a reaches a predetermined lower limit (step S23). The measured value of the first pressure sensor 41a installed on the branch line 30a is equal to the pressure of the first gas tank 10a. There is a positive correlation between the remaining amount of gas in the tank and the pressure; when the pressure of the gas tank reaches the lower limit, the remaining amount of gas in the tank also reaches the lower limit. That is, the processing in step S23 is equivalent to "remaining in standby mode until the remaining amount of the first gas tank 10a reaches the lower limit".

[0055] When the pressure in the first gas tank 10a reaches the lower limit, the controller 50 moves the first gas tank 10a towards the sealing position (step S24). The automatic closing valve of the first gas tank 10a closes. Next, the controller 50 implements control over the second gas tank 10b. Figure 4 Gas leak inspection and handling (step S25).

[0056] When performing on the second gas tank 10b Figure 4 During gas leak inspection and handling, it is determined whether a gas leak has occurred at the seal 12 of the second gas tank 10b. If the seal of the second gas tank 10b is normal, the controller 50 moves the second gas tank 10b to the open valve position and opens the shut-off valve 31. Figure 4 Steps S17, S18, and S19: The automatic shut-off valve of the second gas tank 10b opens, and the shut-off valve 31 also opens, supplying hydrogen from the second gas tank 10b to the fuel cell 90. After hydrogen supply from the second gas tank 10b to the fuel cell 90 begins, the user replaces the first gas tank 10a. After the new first gas tank 10a is installed, the process begins... Figure 6 Gas leak inspection and handling.

[0057] If the seal of the second gas tank 10b is faulty, the controller 50 outputs a sealing fault signal indicating an abnormality at the seal 12 of the second gas tank 10b. Figure 4 Step S17: No, S20). Upon receiving the sealing abnormality signal, the display device 51 outputs a message indicating a gas leak at the seal 12 of the second gas tank 10b (the display device 51 illuminates a warning light or emits a warning sound). Then, the controller 50 stops the system. Figure 4 Step S21).

[0058] Furthermore, during the gas leak check of the second gas tank 10b, hydrogen gas, which is filled in the gas supply pipe 30 downstream of the shut-off valve 31, is continuously supplied to the fuel cell 90. That is, hydrogen gas continues to be supplied to the fuel cell 90 even during the gas leak check process. It is not necessary to shut down the fuel cell 90 during the gas leak check process.

[0059] By having multiple gas tanks, the gas supply system 2a can switch to another gas tank while supplying hydrogen from one gas tank to the fuel cell 90.

[0060] Notes related to the technologies described in the embodiments are provided. In the second embodiment, the gas supply system 2a has two gas cylinders. The gas supply system disclosed in this specification may also have three or more gas cylinders. The controller 50, which detects a gas leak at the seal 12, outputs a sealing abnormality signal indicating that a gas leak has occurred. The sealing abnormality signal may also be output to a host computer that manages the gas supply system or to a terminal of the personnel managing the gas supply system.

[0061] In this embodiment, the gas supply system 2 (2a) supplies hydrogen to the fuel cell 90. The fuel cell 90 is an example of a gas-consuming device. The gas-consuming device supplied by the gas supply system 2 (2a) can also be a device other than the fuel cell 90. The pressure of the gas suitable for operation of the gas-consuming device is lower than the internal pressure of the gas tank 10. Therefore, during the gas leak detection and handling process, the gas-consuming device can be continuously operated using the gas accumulated in the gas supply pipe 30 downstream of the shut-off valve 31.

[0062] The controller performs the following gas leak check procedure: (1) The controller 50 controls the actuator 19 to advance the gas canister 10 until the automatic shut-off valve 20 is pushed open. Then, while maintaining the seal of the connection space S, the controller 50 retracts the gas canister 10 to the closed position of the automatic shut-off valve 20 and closes the shut-off valve 31. (2) After a predetermined time, if the measured value of the first pressure sensor 41 is higher than the measured value of the second pressure sensor 42, the controller 50 advances the gas canister 10 to reopen the automatic shut-off valve 20 and opens the shut-off valve 31. On the other hand, if the measured value of the first pressure sensor 41 is lower than the measured value of the second pressure sensor 42, the controller 50 outputs a sealing abnormality signal indicating that a gas leak has occurred. Furthermore, the shut-off valve 31 is opened before the gas leak check procedure.

[0063] In the gas supply system 2a of the second embodiment, the shut-off valve 31 is located downstream of the branch point of the gas supply pipe. The shut-off valve can also be located on each of the branch lines 30a, 30b. A check valve can also be installed upstream or downstream of the shut-off valve 31. The check valve allows gas to flow from upstream to downstream and prevents gas from flowing from downstream to upstream. As described above, "downstream" refers to the side of the gas supply pipe 30 closer to the fuel cell 90 (gas consumption device), and "upstream" refers to the side closer to the gas tank 10.

[0064] Even if a check valve is installed instead of shut-off valve 31, gas leak checks can still be performed. However, by having shut-off valve 31, gas can be reliably prevented from flowing back from the downstream side (gas consumption equipment side) to the upstream side (gas tank side).

[0065] The specific examples of the present invention have been described in detail above, but these are merely illustrative and do not limit the scope of the claims. The technology described in the claims includes techniques obtained by various modifications and alterations to the specific examples described above. The technical elements illustrated in this specification or drawings are technically useful individually or in various combinations, and are not limited to the combinations described in the claims at the time of application. Furthermore, the technology illustrated in this specification or drawings can achieve multiple objectives simultaneously, and achieving one of these objectives is itself technically useful.

Claims

1. A gas supply system, wherein, The gas supply system includes: The gas cylinder has an automatic shut-off valve that opens when the push rod is pushed in and closes when the push rod is pulled out; A gas supply pipe is connected to the gas tank and has the push rod at the front end to guide the gas in the gas tank to the gas consumption device. An actuator causes the gas tank to move forward or backward relative to the gas supply pipe; The seal, when the distance between the automatic shut-off valve and the push rod is shorter than a specified threshold distance, will include sealing the connection space between the opening of the automatic shut-off valve and the front end of the gas supply pipe; A shut-off valve is installed in the gas supply pipe; A first pressure sensor measures the pressure in the gas supply pipe upstream of the shut-off valve; A second pressure sensor measures the pressure in the gas supply pipe downstream of the shut-off valve; as well as Controller The controller controls the actuator to advance the gas cylinder until the automatic shut-off valve is opened. Then, while maintaining the seal of the connection space, the gas cylinder is retracted until the automatic shut-off valve is closed, and the shut-off valve is closed. After a predetermined time, if the measured value of the first pressure sensor is higher than the measured value of the second pressure sensor, the controller advances the gas tank to reopen the automatic shut-off valve and open the shut-off valve. If the measured value of the first pressure sensor is lower than the measured value of the second pressure sensor, the controller outputs a signal indicating that a gas leak has occurred.

2. The gas supply system according to claim 1, wherein, The gas supply pipe is divided into multiple branches. The first pressure sensor and the push rod are installed in each of the branch paths. The gas tank is connected to each of the branch lines.

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