Liquefied gas supply device

Abstract

To provide a liquefied gas supply device that can quickly supply liquefied gas to the recipient. [Solution] This liquefied gas supply device comprises a housing capable of accommodating a liquefied gas container, a first pipe located inside the housing and including a first end connected to the liquefied gas container and a second end opposite to the first end, a second pipe connected to the first pipe at the second end and located inside the housing, a third pipe including a third end connected to the second pipe and a fourth end exposed to the outside of the housing, a first valve unit installed in the first pipe that can switch between a closed state and an open state between the first pipe and the second pipe, and a second valve unit installed in the third pipe that can switch between a closed state and an open state between the second pipe and the third pipe. The second pipe includes a liquefied gas containment section, to which a differential pressure type liquid level detection device capable of detecting the liquid level of the liquefied gas is connected. When the liquefied gas is at its maximum liquid level, more than 50% of the volume of the liquefied gas containment section is in the gas phase.

Description

Technical Field

[0001] The present disclosure relates to a liquefied gas supply device.

Background Art

[0002] As a device for supplying liquefied gas filled in a liquefied gas container to a supply destination, a cylinder cabinet is known (for example, see Patent Document 1). In the cylinder cabinet disclosed in Patent Document 1, the flow rate of the gas flowing to the supply destination is measured by a flow meter installed near the gas supply port.

[0003] In the cylinder cabinet described in Patent Document 2, a part of the pipe arranged in the cabinet and connected to the liquefied gas container can be partitioned from other parts by a valve and is made of a thick-diameter pipe. The cylinder cabinet described in Patent Document 2 temporarily stores liquefied gas in this thick pipe portion and grasps the mass of the liquefied gas discharged from the cylinder cabinet by measuring the mass of this portion with a platform scale or the like.

[0004] The cylinder cabinet described in Patent Document 3 can install a liquefied gas cylinder below in the cabinet (housing), and is configured such that a mass measurement unit is located above the liquefied gas cylinder. The cylinder cabinet of Patent Document 3 also grasps the mass of the liquefied gas discharged from the cylinder cabinet by measuring the mass of a part of the pipe that can be partitioned from other parts.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

[0006] It is desirable that the gas supply from the cylinder cabinet be carried out quickly. One of the objectives of this disclosure is to provide a liquefied gas supply device that can quickly supply liquefied gas to the recipient. [Means for solving the problem]

[0007] A liquefied gas supply device according to this disclosure comprises: a housing capable of housing a liquefied gas container; a first pipe disposed inside the housing, including a first end connected to the liquefied gas container and a second end opposite to the first end; a second pipe connected to the first pipe at the second end and disposed inside the housing; a third pipe including a third end connected to the second pipe and a fourth end exposed to the outside of the housing; a first valve unit installed in the first pipe capable of switching between a closed state in which the space between the first pipe and the second pipe is closed and an open state in which it is open; and a second valve unit installed in the third pipe capable of switching between a closed state in which the space between the second pipe and the third pipe is closed and an open state in which it is open. The second pipe includes a liquefied gas storage section capable of housing liquefied gas, and a differential pressure type liquid level detection device capable of detecting the liquid level of the liquefied gas stored in the liquefied gas storage section is connected to the liquefied gas storage section. In the liquefied gas containment section, when the liquefied gas is at its maximum liquid level, more than 50% of the volume of the liquefied gas containment section is in the gas phase. [Effects of the Invention]

[0008] According to this disclosure, gas can be supplied to customers quickly. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 shows the inside of the enclosure with the cylinder cabinet installed, viewed from the left side of the enclosure. [Figure 2]Figure 2 shows the exterior of the enclosure with the cylinder cabinet installed, viewed from the left side of the enclosure. [Figure 3] Figure 3 shows the exterior of the enclosure with the cylinder cabinet installed, viewed from the front of the enclosure. [Figure 4] Figure 4 is a conceptual diagram showing the internal structure and piping of a cylinder cabinet. [Figure 5] Figure 5 is a flowchart showing an example of the control procedure by the control unit. [Figure 6] Figure 6 is a flowchart showing an example of the procedure for vessel exhaust. [Figure 7] Figure 7 is a flowchart showing an example of the initial filling procedure for a vessel. [Figure 8] Figure 8 is a flowchart showing an example of a gas metering procedure. [Figure 9] Figure 9 is a flowchart showing an example of the gas supply procedure. [Figure 10] Figure 10 is a flowchart showing an example of the procedure for exhausting the discharge line. [Figure 11] Figure 11 is a schematic diagram showing the configuration of the vessel and the connection of the liquid level detection device. [Figure 12] Figure 12 is a schematic diagram showing the configuration of the vessel and the connection of the liquid level detection device. [Figure 13] Figure 13 is a schematic diagram showing the configuration of the vessel and the connection of the liquid level detection device. [Figure 14] Figure 14 is a schematic diagram showing the configuration of the vessel and the connection of the liquid level detection device. [Figure 15] Figure 15 is a schematic diagram showing the configuration of the vessel and the connection of the liquid level detection device. [Modes for carrying out the invention]

[0010] [Summary of the Embodiment] The liquefied gas supply device according to the present disclosure includes a housing capable of accommodating a liquefied gas container therein, a first end connectable to the liquefied gas container, and a second end opposite to the first end. The device further includes a first pipe disposed inside the housing, a second pipe connected to the first pipe at the second end and disposed inside the housing, and a third pipe including a third end connected to the second pipe and a fourth end exposed outside the housing. A first valve portion is installed on the first pipe and is capable of realizing a first switching for switching between a closed state in which the space between the first pipe and the second pipe is blocked and an open state in which the space is opened. A second valve portion is installed on the third pipe and is capable of realizing a second switching for switching between a closed state in which the space between the second pipe and the third pipe is blocked and an open state in which the space is opened. The second pipe includes a liquefied gas storage portion capable of storing liquefied gas, and a differential pressure type liquid level detection device capable of detecting the liquid level of the liquefied gas stored in the liquefied gas storage portion is connected to the liquefied gas storage portion. In a state where the liquefied gas reaches the maximum liquid level, 50% or more of the capacity of the liquefied gas storage portion is in the gas phase. The low-pressure side pressure guiding pipe of the liquid level detection device may be connected to a position 50% or less of the capacity of the liquefied gas storage portion.

[0011] In a liquefied gas supply device, it is desired to be able to quickly supply liquefied gas to a supply destination. At the same time, it is necessary to accurately grasp the amount of liquefied gas to be supplied and accurately supply a predetermined amount of liquefied gas to the supply destination. Conventionally, in order to measure the amount of liquefied gas to be supplied, it has been proposed to measure the mass of a pipe that temporarily stores liquefied gas and measure the amount of liquefied gas from that mass (Patent Documents 2 and 3). However, the need for a quick and accurate gas supply continues, and a configuration for measuring the gas amount more quickly has been studied.

[0012] Instead of measuring the amount of gas contained in a pipe from the mass of the pipe, it was conceived to detect the amount of gas itself contained in the pipe, and in a form including a liquefied gas storage section in a second pipe that can be partitioned from other parts by opening and closing a valve, a configuration including a differential pressure type liquid level detection device capable of detecting the liquid level of the liquefied gas contained in this liquefied gas storage section was considered. In this consideration, it was found that when the liquefied gas is discharged at high speed from a liquefied gas storage section filled with 80 to 90% or more of liquefied gas, turbulence of the liquid surface occurs and it tends to be difficult to perform rapid and accurate liquid level measurement. Studies were made to solve this problem, and by taking a sufficient proportion of the gas phase with respect to the capacity of the liquefied gas storage section, a rapid pressure drop due to the liquid level drop during liquefied gas discharge was suppressed, and the accompanying boiling of the liquid phase part and the turbulence of the liquid surface could be suppressed, and it was found that rapid liquid level measurement became possible. The liquefied gas storage section of the gas supply device according to the present disclosure is configured such that 50% or more of the capacity of the liquefied gas storage section is in the gas phase even in a state where the liquefied gas reaches the maximum liquid level. With this configuration, even when the liquefied gas is discharged rapidly, boiling of the liquefied gas and turbulence of the liquid surface are suppressed, and gas supply can be performed while accurately measuring the amount of liquefied gas. Such an effect can be obtained by a device in which a pressure guiding pipe for measuring the pressure of the gas phase part is connected to a position that is always in the gas phase part and is 50% or less of the capacity of the gas storage section.

[0013] In the liquefied gas supply device, in the first pipe, the pipe between the first valve part and the second end part may be composed of a metal pipe. In a liquefied gas supply device of a type that measures the gas amount from the mass of the pipe, since it is necessary to measure only the weight of a specific part (second pipe) in the continuous pipe, the pipe part connected to the pipe to be measured was composed of a lightweight resin tube. On the other hand, in the liquefied gas supply device according to the present disclosure, since the amount of liquefied gas contained in the pipe is measured, the weight of the pipe itself does not become a problem. For this reason, the connection part to the second pipe that stores the liquefied gas to be measured can be composed of a metal pipe, and a liquefied gas supply device that can perform liquid feeding more stably and has excellent durability can be configured.

[0014] In the liquefied gas supply device described above, the distance from the first valve section to the second end in the first piping may be approximately 5 mm to 100 mm. In conventional liquefied gas supply devices, the connection section to the second piping was made of a resin tube, making it impossible to install a valve in this section, resulting in a large distance between the first valve section and the second piping. In contrast, in the liquefied gas supply device according to this disclosure, the connection section to the second piping is made of a metal pipe, which shortens the distance from the first valve section to the second end. As a result, responsiveness is improved, and the amount of gas can be measured and supplied more quickly.

[0015] In the liquefied gas supply device, a purge gas pipe may be further connected to the third pipe, allowing purge gas to be introduced into the third pipe. With this configuration, the third pipe and the pipes within the supply device can be purged with purge gas as needed, enabling safer operation of the supply device.

[0016] The liquefied gas supply device may further include a control unit that controls the first switching and the second switching based on the liquid level in the second pipe measured by the measuring device. By the control unit controlling the switching by the first valve and the second valve based on the liquid level in the second pipe measured by the measuring device, gas metering and gas supply can be performed more easily and quickly.

[0017] [Specific examples of embodiments] Next, an example of a specific embodiment of a liquefied gas supply device according to this disclosure will be described with reference to the drawings. In the following drawings, the same or corresponding parts are given the same reference numerals, and their descriptions will not be repeated.

[0018] In Figures 1 to 3, the X direction represents the width of cylinder cabinet A when it is installed. The Y direction represents the depth of cylinder cabinet A when it is installed. The Z direction represents the height (vertical direction) of cylinder cabinet A when it is installed.

[0019] [Cylinder Cabinet] Figure 4 shows the configuration of the cylinder cabinet A (liquefied gas supply device) in the embodiment. In Figure 4, the dashed lines conceptually show the paths through which control signals are sent from the on / off valve AV1 to AV710 and the gas detector 13 under the control of the control unit 9. The dashed-dotted line conceptually shows the state in which the measurement unit 8 is connected to the control unit 9 in a communicative manner.

[0020] First, with reference to Figure 4, the components of the cylinder cabinet A, which is one embodiment of the liquefied gas supply device according to this disclosure, will be described.

[0021] Cylinder cabinet A is a gas supply device that houses liquefied gas container B and supplies the liquefied gas filled in liquefied gas container B to a destination (not shown) via piping. An example of a destination includes a refrigerator. Some of the liquefied gas may vaporize inside liquefied gas container B. Examples of liquefied gases include propane gas (R290), ethane gas (R170), and carbon dioxide gas.

[0022] Referring to Figure 4, the cylinder cabinet A comprises a housing 10, a first pipe 1, a vessel 2 as the second pipe, a third pipe 3, a fourth pipe 4, a fifth pipe 5, a first valve section V1, a second valve section V2, a measuring section 8, and a control section 9. Each component will be described below.

[0023] <Enclosure> Figure 1 is a view of the interior of the housing 10 with the cylinder cabinet A installed, seen from the left side of the housing 10. In the width direction (X-axis direction), the side where the door section 14, described later, is located is the left side. Figure 2 is a view of the exterior of the housing 10 with the cylinder cabinet A installed, from the same viewpoint as in Figure 1. In Figure 2, the components housed inside the housing are shown by dotted lines. In the installed state, the side where the exhaust damper 12, described later, is located is the vertically upward side.

[0024] Referring to Figures 1 and 4, the exhaust damper 12 and the gas detector 13 are installed on the top of the housing 10. The exhaust damper 12 is positioned on the top surface 10t of the housing 10. By operating a fan (not shown) installed inside the exhaust damper 12, the gas inside the housing 10 is discharged from the exhaust damper 12, thereby maintaining negative pressure inside the housing 10. The exhaust damper 12 is an exhaust section capable of discharging air from the inside of the housing 10 to the outside. The gas detector 13 may be a suction-type gas detector. The gas detector 13 is installed near the ceiling inside the housing 10. The gas detector 13 is connected to the exhaust damper 12 and can monitor for gas leakage inside the housing 10. The housing 10 is equipped with a negative pressure gauge NPG for measuring the internal pressure of the housing 10 and is connected to the control unit 9.

[0025] The housing 10 is capable of housing a liquefied gas container B inside. The housing 10 has a shape such as a rectangular parallelepiped, but its shape is not limited. Referring to Figure 1, the housing 10 includes, inside, retaining chains 16a and 16b connected to brackets 17a and 17b, respectively, and a shelf 18. The brackets 17a and 17b are support parts for holding the liquefied gas container B in a predetermined position. Both brackets 17a and 17b are located below the center in the height direction (Z direction) of the housing 10 so that the liquefied gas container B can be placed on the floor surface 10c of the housing 10. The shelf 18 is a base part for placing the vessel 2 as a second pipe. The shelf 18 is located above the center in the height direction of the housing 10 so that the vessel 2 is positioned above the liquefied gas container B. The housing 10 has, on its exterior, an exhaust damper 12 and a control box 15 housing the control unit 9.

[0026] Referring to Figure 1, the retaining chains 16a and 16b hold the liquefied gas container B. Retaining chain 16b is located below retaining chain 16a. Both ends of retaining chain 16a are connected to brackets 17a located inside the rear wall portion 10a of the housing 10. Both ends of retaining chain 16b are connected to brackets 17b located inside the rear wall portion 10a of the housing 10.

[0027] Referring to Figures 1 and 4, the vessel 2 is positioned on the shelf 18. The measuring unit 8 connected to the vessel 2 is a differential pressure type liquid level detection device, specifically a differential pressure transmitter. In the example in Figure 1, the measuring unit 8 is positioned below the shelf 18, but the installation position is not restricted. In the installed state of the cylinder cabinet A, the vessel 2 is positioned vertically above the liquefied gas container B.

[0028] Referring to Figures 1 to 3, the housing 10 has an openable and closable door section 14. Figure 2 shows the door section 14 in the closed position. The entire door section 14 is made of metal, such as stainless steel, and has a viewing window 42 and an opening / closing handle (not shown). The viewing window 42 is made of a transparent material that allows the interior to be seen, such as wired glass.

[0029] Referring to Figure 2, the door 14 is located on the left side of the housing 10. The rear end 14b of the door 14 is pivotally attached to the rear wall of the housing 10 via a hinge. When the door 14 is opened, the housing 10 is sealed by closing the door 14, which allows the liquefied gas container B to be inserted into and removed from the housing 10.

[0030] Referring to Figure 3, a control box 15 is positioned at the top of the front of the housing 10. The control box 15 is installed on the outside of the front wall portion 10b of the housing 10. The control box 15 houses the control unit 9. The front surface of the control box 15 is equipped with a touch panel display unit 71, a power button 72, and an emergency shut-off button 73. The display unit 71 displays commands from the control unit 9 and also detects the operator's actions. An air intake port 41 is provided on the front or back of the housing 10. The air intake port 41 is an intake section that can draw outside air from the outside of the housing 10 into the inside of the housing 10. The air intake port 41 may be, for example, a louver with multiple openings that can be opened and closed. The lower end 41b of the air intake port 41 is located at approximately the same position as the floor surface 10c in the height direction (Z direction), or slightly above it. The upper end 41t of the air intake port 41 is located in the height direction at a position that overlaps with the body of the liquefied gas container B housed inside the housing 10.

[0031] When the door section 14 is closed and the fan (not shown) installed inside the exhaust damper 12 is activated, the gas inside the housing 10 is discharged from the exhaust damper 12, and outside air is drawn into the housing from the intake port 41. The inside of the housing 10 is kept under negative pressure, and an airflow is generated inside the housing from the intake port 41 toward the exhaust damper 12. Near the exhaust damper 12, the pressure drops, and the temperature may drop due to depressurization and expansion. Air at the same temperature and pressure as the outside air is drawn into the housing 10 from the intake port 41.

[0032] <First piping> Referring to Figure 1, the first pipe 1 includes a first end E1 that can be connected to the liquefied gas container B, and a second end E2 which is the end opposite to the first end E1. The first pipe 1 is housed inside the housing 10.

[0033] Referring to Figure 4, the first piping 1 includes a flexible hose FP and a first metal pipe P1 connected in order from the first end E1 to the second end E2. An inlet valve Va is installed at the point where the flexible hose FP and the first metal pipe P1 are connected.

[0034] A check valve CV1 is installed on the flexible hose FP. The first metal pipe P1 has a filter FL, an on-off valve AV1, and a first valve section V1 installed in order from the flexible hose FP toward the second metal pipe P2. By switching the on-off valves AV3 and AV4 included in the first valve section V1, the connection between the first piping 1 and the vessel 2 is switched between a closed state and an open state. The first piping 1 includes a main pipe and a bypass pipe formed in the first metal pipe P1. The bypass pipe is connected to the region of the first metal pipe P1 between the portion where the on-off valve AV1 is installed and the portion where the first valve section V1 is installed, and to the region of the first metal pipe P1 between the portion where the first valve section V1 is installed and the portion connected to the second end E2. An on-off valve AV3 and a micro-flow control valve FV1 are provided in the main pipe. An on-off valve AV4 and a micro-flow control valve FV2 are provided in the bypass pipe.

[0035] The on-off valve AV1 is, for example, an air-operated valve. The dashed lines in Figure 4 conceptually show the piping for sending the pneumatic signal, which is a control signal sent to the air-operated valve by the control unit 9. The same applies to the on-off valves AV2 to AV11, which will be described later.

[0036] Referring to Figures 1 to 3, in the installed state of cylinder cabinet A, the first end E1 of the first pipe 1 is located vertically below the second end E2. The second end E2, which is the inlet to vessel 2, is located vertically above the first end E1, which is the outlet to liquefied gas container B. Furthermore, the first end E1 is located vertically above the intake port 41 of housing 10.

[0037] In the first piping 1, the piping between the first valve section V1 and the second end section E2 is made of metal. Conventionally, the piping between the first valve section V1 and the second end section E2 was made of resin tubing, but by making this section a metal tube, the distance between the first valve section V1 and the second end section E2 can be reduced. In other words, the first valve section V1 can be positioned closer to the vessel 2. This makes the flow of liquefied gas smoother when filling the vessel 2 from the first piping 1, and improves responsiveness. The distance from the first valve section V1 to the second end section E2 can be set appropriately depending on the size of the entire device, but for example, it may be 100 mm or less.

[0038] <Second piping (vessel)> Referring to Figure 4, the vessel 2, as the second pipe, is connected to the first pipe 1 at its second end E2, and its entirety is housed inside the housing 10. Referring to Figures 1 and 2, with the cylinder cabinet A installed, the vessel 2 is positioned vertically above the liquefied gas container B. When installed, the vessel 2 has an internal cylindrical section that extends vertically, and the liquefied gas is contained in this cylindrical section. The cylindrical section is the liquefied gas containment section. The vessel 2 is made of stainless steel pipe, such as SUS304 according to JIS (Japanese Industrial Standards) standards. The vessel 2 may have an inner diameter larger than the inner diameter of the first pipe 1. The inner diameter of the vessel 2 may be, for example, 25 mm or more and 160 mm or less. The vessel 2 can be constructed using pipes of approximately 25A to 150A as specified in JIS G3452, for example. Typically, 50A pipes can be used.

[0039] A measuring unit 8 capable of detecting the liquid level of the liquefied gas contained in the vessel 2 is connected to the vessel 2. The measuring unit 8 may be a differential pressure type liquid level detection device, and more specifically, a differential pressure transmitter. The measuring unit 8 is electrically connected to a control unit 9, and information regarding the liquid level of the liquefied gas in the vessel 2 is transmitted from the measuring unit 8 to the control unit 9.

[0040] Figures 11 to 15 are schematic diagrams showing the configuration of the vessel and an example of the connection of the liquid level detection device. Referring to Figure 11, a differential pressure type liquid level detection device 800 is connected to the vessel 201 as the second pipe, as the measuring unit. The vessel 201 has a cylindrical liquefied gas containment section that extends vertically when installed. The differential pressure type liquid level detection device 800 is equipped with a low-pressure side pressure sensing pipe 801 and a high-pressure side pressure sensing pipe 802, each connected to the vessel 201. The high-pressure side pressure sensing pipe 802 is connected near the bottom of the vessel. The pressure on the liquid phase side (high-pressure side) is measured by the high-pressure side pressure sensing pipe 802. The low-pressure side pressure sensing pipe 801 is connected below the center in the height direction of the vessel 201. The vessel 201 has a vertically elongated shape, and even when the liquefied gas is at its maximum liquid level (shown as Lh in Figure 11), more than 50% of the vessel 201 is in the gas phase.

[0041] When a vessel contains liquefied gas and most of it (e.g., 80% or more) is in the liquid phase, if the liquefied gas is discharged in a short time and the liquid level drops, the pressure in the gas phase drops rapidly, causing adiabatic expansion, which can lead to a decrease in temperature and boiling of the liquid phase. When this phenomenon occurs, the liquid level becomes turbulent, making accurate liquid level measurement difficult. In this respect, Vessel 201 has sufficient length in the vertical direction, and even at the maximum liquid level, more than 50% is in the gas phase, thereby suppressing the pressure drop when liquefied gas is discharged and enabling rapid and accurate liquid level measurement.

[0042] Referring to Figure 12, the vessel as the second piping is not limited to a straight pipe, and the lower and upper parts of the vessel may have different shapes. The vessel 202 is formed in a T-shape by connecting a horizontally extending pipe section to the upper part of a vertically extending lower pipe. Both the low-pressure side pressure sensing pipe 801 and the high-pressure side pressure sensing pipe 802 of the differential pressure type liquid level detection device 800 are connected to the lower pipe of the vessel 202. The high-pressure side pressure sensing pipe 802 is connected near the bottom of the vessel. The low-pressure side pressure sensing pipe 801 is connected to the lower pipe of the vessel 202. Even when the liquefied gas reaches the maximum liquid level Lh, more than 50% of the vessel 202 is in the gas phase.

[0043] Referring to Figure 13, the vessel 203 has an upper pipe with a larger diameter than the lower pipe connected to the upper part of the lower pipe, which is a smaller diameter cylindrical section. Both the low-pressure side pressure sensing pipe 801 and the high-pressure side pressure sensing pipe 802 of the differential pressure type liquid level detection device 800 are connected to the lower pipe of the vessel 203. The high-pressure side pressure sensing pipe 802 is connected near the bottom of the vessel. The low-pressure side pressure sensing pipe 801 is connected to the lower pipe of the vessel 203. Even when the liquefied gas reaches the maximum liquid level Lh, more than 50% of the vessel 203 is in the gas phase.

[0044] Referring to Figure 14, vessel 204 has a long tube with the top bent to form an L-shaped liquefied gas containment section. Similar to vessels 202 and 203, the differential pressure liquid level detection device 800 is connected to the lower tube of vessel 204.

[0045] Referring to Figure 15, the liquefied gas containment section of the vessel 205 is formed from a first section 205A and a second section 205B connected by a connecting pipe 215. The low-pressure side pressure guide pipe 801 is connected to the upper part of the first section 205A. The second section 205B is always in the gas phase, as the liquefied gas does not reach it even when the liquefied gas is at its maximum liquid level (indicated as Lh in Figure 15), and more than 50% of the vessel 205 is in the gas phase.

[0046] In the examples shown in Figures 11 to 15, the low-pressure side pressure guide pipe 801 is connected at a position less than 50% of the vessel's (liquefied gas containment) volume, but the configuration is not necessarily limited to this. The low-pressure side pressure guide pipe may be connected at a position that is the gas phase of the vessel, that is, at a position more than 50% of the vessel's volume. For example, the low-pressure side pressure guide pipe may be connected at a position that is between 40% and 90% of the vessel's volume.

[0047] <Third piping> The third pipe 3 is a discharge line for discharging the liquefied gas temporarily held in the vessel 2 toward the supply destination. Referring to Figure 4, the third pipe 3 includes a third end E3 connected to the vessel 2 and a fourth end E4 exposed to the outside of the housing 10. Near the fourth end E4, an on-off valve AV11 and a check valve CV7 are provided. Another component, such as a coupler C, may be provided at the outlet portion of the third pipe 3 from the housing 10. Preferably, the third pipe 3 has an inner diameter smaller than the inner diameter of the vessel 2.

[0048] The third piping 3 consists of a second metal pipe P2 and a third metal pipe P3 connected sequentially from the third end E3 to the fourth end E4. The second metal pipe P2 and the third metal pipe P3 are connected to each other via an on-off valve. A second valve section V2 is provided between the third end E3 and the fourth end E4. The third piping 3 includes a main pipe and a bypass pipe formed in the third metal pipe P3. An on-off valve AV5 and a micro-flow control valve FV3 are provided in the main pipe. An on-off valve AV6 and a micro-flow control valve FV4 are provided in the bypass pipe.

[0049] <Fourth piping> Referring to Figure 4, the fourth pipe 4 includes a fifth end E5 connected to the first pipe and a sixth end E6 exposed to the outside of the housing 10. A coupler CP1 is installed at the sixth end E6, which can be connected to a discharge pipe (not shown) for releasing gas into the atmosphere. The fourth pipe 4 is made of metal. On the fourth pipe 4, an on-off valve AV2 and a check valve CV2 are installed in order from the fifth end E5 to the sixth end E6. A pressure gauge PG2 is installed between the on-off valve AV2 and the check valve CV2.

[0050] <Fifth pipe> Referring to Figure 4, the fifth pipe 5 includes a seventh end E7 connected to the vessel 2 and an eighth end E8 connected to the fourth pipe 4 between the on-off valve AV7 and the check valve CV2. The fifth pipe 5 is equipped with the on-off valve AV7 and the micro-flow control valve FV5.

[0051] <Piping for purging> Referring to Figure 4, the purge piping 7 is equipped with a coupler CPC exposed to the outside of the housing 10 and is connected to the third piping 3. Through the coupler CPC, a purge gas (e.g., nitrogen gas) can be introduced into the piping of the cylinder cabinet A from outside the cylinder cabinet A. The purge piping 7 is equipped with a check valve CV4 and an on-off valve AV9 along its course.

[0052] <First Division> Referring to Figure 4, the first valve unit V1 is installed in the first piping 1 and can perform a first switching operation to switch the first piping 1 between a closed state and an open state. The first valve unit V1 includes minute flow control valves FV1 and FV2, and on-off valves AV3 and AV4.

[0053] The shut-off valve AV3 and the minute flow control valve FV2 are installed in the main pipe. The shut-off valve AV4 and the minute flow control valve FV1 are installed in the bypass pipe. The first pipe 1 is closed when the shut-off valves AV3 and AV4 are closed. The first pipe 1 is open when either the shut-off valve AV3 or AV4 is opened.

[0054] <Second Office> Referring to Figure 4, the second valve section V2 is installed in the third piping 3 and is capable of a second switching that switches the third piping 3 between a closed state and an open state. The second valve section V2 includes an on-off valve AV5, a minute flow control valve FV3, an on-off valve AV6, and a minute flow control valve FV4.

[0055] The shut-off valve AV5 and the minute flow control valve FV3 are installed in the main pipe. The shut-off valve AV6 and the minute flow control valve FV4 are installed in the bypass pipe. The third pipe 3 is closed when the shut-off valves AV5 and AV6 are closed. The third pipe 3 is open when either the shut-off valve AV5 or AV6 is opened.

[0056] <Measurement Department> The measurement unit 8 includes a measuring device capable of measuring the liquid level of the liquefied gas contained in the vessel 2. The measuring device may be, for example, a differential pressure type liquid level detection device, and more specifically, a differential pressure transmitter. With the differential pressure type liquid level detection device, the amount of liquefied gas can be measured quickly and accurately during the steps of filling the vessel 2 with a predetermined amount of liquefied gas and discharging the liquefied gas from the vessel 2, and the filling device can be controlled accordingly.

[0057] <Department Head> The control unit 9 controls the opening and closing of the on-off valves AV1 to AV11 installed in the cylinder cabinet A. The control unit 9 controls the first switching by controlling the on-off valves AV3 and AV4 of the first valve section V1. The control unit 9 controls the second switching by controlling the on-off valves AV5 and AV6 of the second valve section V2.

[0058] The control unit 9 is composed of, for example, a PLC (Programmable Logic Controller) including a CPU (Central Processing Unit). The control unit 9 controls the opening and closing of valves AV1 to AV11 by executing a control program such as a ladder program. The input / output section of the control unit 9 is connected to valves AV1 to AV11, a measurement unit 8, a display unit including an LCD panel, and an operation reception unit including a touch panel that receives input operations from the operator.

[0059] <Discharge piping> In addition to the components described above, as shown in Figure 4, cylinder cabinet A includes discharge pipes 6a, 6b, 6c, and 6d. Discharge pipes 6a, 6b, 6c, 6d, and 6e are for discharging liquefied gas to the outside of the housing 10 in an emergency.

[0060] One end of the discharge pipe 6a is connected to the area between the on-off valve AV1 and the first valve section V1 in the first piping 1, and the other end is connected to the safety valve SV1. A pressure gauge PG1 is installed on the discharge pipe 6a. The discharge pipe 6b is connected to the safety valve SV2. The discharge pipe 6c is connected to the safety valve SV3. The discharge pipe 6d is also connected to the safety valve SV2. The on-off valve AV8 and the check valve CV3 are installed on the discharge pipe 6e.

[0061] <Vacuum line> Cylinder cabinet A includes a first vacuum line 6g and a second vacuum line 6h. The first vacuum line 6g is equipped with an on-off valve V10 and a check valve CV5. The first vacuum line 6g includes a coupler CP2. The second vacuum line 6h is equipped with a check valve CV6. The second vacuum line 6h includes a coupler CP3. Couplers CP2 and CP3 are each provided to be exposed to the outside of the housing 10. A vacuum pump VP is installed outside the housing 10, and the vacuum pump VP is connected to couplers CP2 and CP3, respectively, via piping.

[0062] <Hot water chiller> Furthermore, a hot water chiller 45 is provided as a heating device near the intake port 41 in the cylinder cabinet A. When a hot water chiller 45 is provided, it is possible to keep the temperature of the intake port 41 of the housing 10 higher than the outside air temperature, so that gas supply using the cylinder cabinet A can be carried out quickly even when the outside air temperature is low, such as in winter.

[0063] [Control procedure by the control unit] Figure 5 is a flowchart showing an example of the control procedure by the control unit 9.

[0064] The general outline of the control by the control unit 9 in this embodiment will be described with reference to Figure 5. Note that some explanations and illustrations of operations performed by the operator, such as the removal of the supply destination, the piping connected to the supply destination, and the vacuum pump from couplers CP2 and CP3, as well as other controls such as the start or stop operation of the vacuum pump, have been omitted. In the initial state of control by the control unit 9, the on-off valve AV1 is open, and the on-off valves AV2 to AV11 are closed.

[0065] Referring to Figure 5, in step ST1, the control unit 9 performs a "vessel exhaust" process to empty the vessel 2.

[0066] In step ST2, the control unit 9 performs a "vestment initial filling" process in which a predetermined amount of liquefied gas is filled into the vessel 2 that was exhausted in step ST1.

[0067] In step ST3, the control unit 9 performs a "gas metering" process in which it further fills the vessel, which was filled with a predetermined amount of liquefied gas in step ST2, with liquefied gas, and temporarily stores the liquefied gas to be supplied to the recipient in the vessel.

[0068] In step ST4, the control unit 9 performs a "gas supply" process, which involves discharging liquefied gas from a vessel filled with a predetermined amount of liquefied gas in step ST3 to the recipient.

[0069] Figure 6 is a flowchart of an example of the vessel exhaust procedure. Figure 7 is a flowchart of an example of the vessel initial filling procedure. Figure 8 is a flowchart of an example of the gas metering procedure. Figure 9 is a flowchart of an example of the gas supply procedure. Figure 10 is a flowchart of an example of the discharge line exhaust procedure performed during the gas metering procedure.

[0070] Referring to the flowcharts in Figures 6 to 9, the detailed procedures for each process in steps ST1 to ST3 will be explained.

[0071] <Vessel exhaust> Referring to Figures 4 and 6, the control unit 9 performs exhaust from the vessel 2 in response to the operator's button press. In step ST11, the operator presses down the exhaust button on the device. In step ST12, the control unit 9 displays "Exhaust Confirmation" and "Yes / No" on the display screen. If "No" is pressed (NO in ST12), the display ends. If "Yes" is pressed (YES in ST12), the control unit 9 displays "Exhaust?" and "Yes / No" on the display screen in step ST13. If "No" is pressed (NO in ST13), the display ends. If "Yes" is pressed (YES in ST13), the control unit 9 opens the on-off valve AV7 in step ST14. In step ST15, the control unit 9 displays the value of the pressure gauge PG2 on the display unit, and the operator confirms the value of the pressure gauge PG2. In step ST16, the control unit 9 displays "Exhaust Complete" and "Yes" on the display screen. After confirming that the pressure has decreased and exhaust has been performed, if "Yes" is pressed in step ST16, the control unit 9 closes the on-off valve AV7 in step ST17, and the vessel exhaust is completed.

[0072] <Initial filling> To accurately supply liquefied gas to the recipient, a predetermined amount of liquefied gas is pre-filled into vessel 2. Specifically, an "initial filling" is performed, in which a predetermined initial inflow amount of liquefied gas (for example, 10% to 30% or 5% to 10% of the volume of vessel 2) is introduced into vessel 2 from liquefied gas container B. The details are explained below with reference to Figure 7.

[0073] Referring to Figure 7, the control unit 9 starts the initial filling of the vessel 2 in response to the operator's button press. In step ST21, the control unit 9 displays "Do you want to start initial filling?" and "Yes / No" on the display screen. If "No" is pressed (NO in ST21), the display ends. If "Yes" is pressed (YES in ST21), the control unit 9 opens the on-off valve AV4 in step ST22. With the on-off valve AV4 open, the first piping 1 becomes open and liquefied gas flows into the vessel 2. If the inflow rate of the liquefied gas is below a set value, control can be performed to promote inflow by opening the on-off valve AV2.

[0074] In step ST23, the control unit 9 performs fine adjustments by closing the on-off valve AV4 of the first valve section V1 and then opening the on-off valve AV3, thereby allowing a small amount of liquefied gas to flow further into the vessel 2 from the liquefied gas container B through the minute flow rate adjustment valve FV2. When the liquid level in the vessel 2 reaches a predetermined value, the control unit 9 closes the on-off valve AV3 to close the first piping 1 and then executes step ST24. In step ST24, the control unit 9 determines whether the liquid level of the liquefied gas in the vessel 2 is below a predetermined initial allowable value. The initial allowable value is set higher than the liquid level corresponding to the initial inflow amount. If the control unit 9 determines that the liquid level in the vessel 2 is below the initial allowable value (YES in ST24), it executes step ST26 and displays "Initial filling complete" on the display unit.

[0075] If the control unit 9 determines that the liquid level in vessel 2 exceeds the initial allowable value (NO in ST24), it executes step ST25. In step ST25, the control unit 9 opens the on-off valve AV2 to release the excess liquefied gas that has flowed into vessel 2 to the outside of cylinder cabinet A via the fifth pipe 5. The control unit 9 monitors the liquid level in vessel 2, which is measured by the measuring unit 8. When the liquid level in vessel 2 reaches the initial allowable value, the control unit 9 closes the on-off valve AV2 and then executes step ST26.

[0076] <Gas Metering> Referring to Figure 8, the control unit 9 starts filling the vessel 2 with gas in response to the operator's button press. In step ST31, the control unit 9 displays "Start gas filling?" and "Yes / No" on the display screen. If "No" is pressed (NO in ST31), the display ends. If "Yes" is pressed (YES in ST31), the control unit 9 performs exhaust of the discharge line (third piping) in step ST32. The procedure for exhausting the discharge line will be described later.

[0077] Next, in step ST33, the control unit 9 opens the on-off valve AV4. When the on-off valve AV4 is open (i.e., the first valve section V1 is open), the first piping 1 becomes open and liquefied gas flows into the vessel 2. If the inflow rate of the liquefied gas is below a set value, control can be performed to promote the inflow by opening the on-off valve AV2. The duration of step ST33 may be a preset time, or the control unit 9 may monitor the liquid level measurement value of the vessel 2 from the measurement unit 8 and determine the duration of step ST33.

[0078] Next, in step ST34, the control unit 9 closes the on-off valve AV4 of the first valve unit V1 and then opens the on-off valve AV3, thereby allowing a small amount of liquefied gas to flow from the liquefied gas container B into the vessel 2 through the minute flow rate adjustment valve FV2. The duration of step ST34 may be a preset time, or the control unit 9 may monitor the liquid level measurement value of the vessel 2 from the measurement unit 8 and determine the duration of step ST34.

[0079] Following step ST34, the control unit 9 closes the first piping 1 by closing the on-off valve AV3, and then executes step ST35. In step ST35, the control unit 9 determines whether the liquid level of the liquefied gas flowing into the vessel 2 is below a predetermined allowable value. The allowable value is set higher than the amount corresponding to the supply amount.

[0080] If the control unit 9 determines that the liquid level of the liquefied gas in the vessel 2 is below the allowable value, it terminates the "gas metering" process. If the control unit 9 determines that the liquid level in the vessel 2 exceeds the allowable value, it executes step ST36.

[0081] In step ST36, the control unit 9 opens the on-off valve AV2, releasing the excess liquefied gas that has flowed into the vessel 2 to the outside of the cylinder cabinet A via the fifth pipe 5. At this point, the control unit 9 monitors the liquid level in the vessel 2, which is measured by the measuring unit 8. When the liquid level in the vessel 2 reaches an acceptable value, the control unit 9 closes the on-off valve AV2 and then terminates the "gas metering" process.

[0082] <Gas supply> After a predetermined amount of gas is stored in the vessel 2 by the "gas metering" described above, the liquefied gas is then dispensed from the vessel 2 to the recipient (gas supply). The control unit 9 controls the switching of the second valve unit V2 based on timer control or the liquid level in the vessel 2 measured by the measuring unit 8, thereby supplying the liquefied gas metered in step ST3 from the vessel 2 to the recipient. Specifically, this will be explained below with reference to Figure 9.

[0083] In step ST41, the control unit 9 opens the third pipe 3 by opening the on-off valve AV6 of the second valve section V2 and the on-off valve AV11 provided on the supply pipe located outside the housing. By opening the third pipe 3, the control unit 9 starts supplying liquefied gas from the vessel 2 to the destination. At this point, the control unit 9 monitors the liquid level in the vessel 2, which is measured by the measuring unit 8. When the liquid level in the vessel 2 reaches a predetermined target value, the control unit 9 executes step ST42. The fifth target value is set lower than the mass corresponding to the supply amount.

[0084] In step ST42, the control unit 9 opens the on-off valve AV5 after closing the on-off valve AV6 of the second valve section V2, thereby supplying a small amount of liquefied gas from inside the vessel 2 through the minute flow rate control valve FV3. At this point, the control unit 9 monitors the liquid level in the vessel 2, which is measured by the measuring unit 8. When the mass of the vessel 2 reaches a predetermined target value, the control unit 9 closes the on-off valve AV5 to close the third piping 3, and then executes step ST43.

[0085] In step ST43, the control unit 9 determines whether the liquid level in vessel 2, including the liquefied gas remaining inside vessel 2, is within a predetermined allowable range. If the control unit 9 determines that the liquid level in vessel 2 is within the allowable range, it terminates the "gas supply" process. If the control unit 9 determines that the mass of the second piping is outside the allowable range, it executes step ST44. In step ST44, the control unit 9 performs error processing. In error processing, the control unit 9 notifies the user of the occurrence of an error with a sound, for example.

[0086] <Discharge line exhaust> The procedure for step ST32, which involves exhausting the discharge line during the aforementioned gas metering process, will now be explained. Prior to supplying gas to the destination via the third piping (discharge line), the control unit 9 performs exhaust of the discharge line (third piping). Prior to exhaust, the vacuum pump VP is started.

[0087] Referring to Figure 10, the control unit 9 determines in step ST51 whether or not to start exhaust. The decision to start exhaust may be based on the operator's input, or other decisions may be made. If it is determined not to start (NO in ST51), the control unit 9 returns to the exhaust start decision. If it is determined to start (YES in ST51), the control unit 9 opens the on-off valve AV8 and performs exhaust (pressure relief). After a certain period of time (e.g., 5 seconds), the control unit 9 determines in step ST52 whether or not to end the exhaust. The decision to end the exhaust may be based on the operator's input, or other decisions may be made based on the elapsed time. If it is determined not to end (NO in ST52), the control unit 9 returns to the exhaust end decision. If it is determined to end (YES in ST52), the control unit 9 closes the on-off valve AV8. Subsequently, the control unit 9 determines in step ST53 whether or not to start nitrogen purging. The decision to start nitrogen purging may be based on the operator's input, or other decisions may be made. If it is determined not to start (NO in ST53), the control unit 9 returns to the nitrogen purging start decision. If it is determined to start (YES in ST53), the control unit 9 opens the on / off valve AV9.

[0088] After a certain period of time (for example, 5 seconds), the control unit 9 determines in step ST54 whether or not to terminate the nitrogen purge. The termination of the nitrogen purge may be determined based on the operator's input, or by checking the elapsed time or other determinations. If it is determined not to terminate (NO in ST54), the control unit 9 returns to the termination determination. If it is determined to terminate (YES in ST54), the control unit 9 closes the on-off valve AV9 and opens the on-off valve AV8. Subsequently, the control unit 9 determines in step ST55 whether or not to perform line vacuuming. The start of line vacuuming may be determined based on the operator's input, or by other determinations. If it is determined not to start (NO in ST55), the control unit 9 returns to the line vacuuming start determination. If it is determined to start (YES in ST55), the control unit 9 closes the on-off valve AV8 and opens the on-off valve AV10.

[0089] After a certain period of time (for example, 5 seconds), the control unit 9 determines in step ST56 whether or not to start vacuuming the workpiece (supply destination). The decision to start vacuuming may be based on the operator's input, or it may be based on confirmation of the elapsed time or other determinations. If it is determined not to start (NO in ST56), the control unit 9 returns to the start determination. If it is determined to start (YES in ST56), the control unit 9 opens the on-off valve AV11. After a certain period of time (for example, 30 seconds), the control unit 9 determines in step ST57 whether or not to end the vacuuming of the workpiece. The decision to end line vacuuming may be based on the operator's input, or it may be based on other determinations. If it is determined not to end (NO in ST57), the control unit 9 returns to the line vacuuming end determination. If it is determined to end (YES in ST57), the control unit 9 closes the on-off valves AV10 and AV11. By performing this operation, liquefied gas can be quickly supplied to the supply destination in the subsequent process.

[0090] <Other processes> When the gas supply (step ST4) is completed, the third pipe 3 is filled with the supplied gas. To repeat the gas supply to the recipient, the gas can be supplied to the recipient quickly by depressurizing and vacuuming the third pipe 3. Specifically, the control unit 9 opens AV8 and holds it for a certain period of time. At this time, the second valve section V2 is closed, and by opening AV8, the gas that has filled the third pipe 3 downstream of the second valve section V2 is released via coupler CP1. Next, the control unit 9 closes AV8 and opens AV10 and holds it for a certain period of time. At this time, by operating the vacuum pump VP, the air downstream of the second valve section V2 in the third pipe 3 is discharged, and the inside of the pipe downstream of the second valve section V2 in the third pipe 3 becomes a vacuum. With this configuration, gas supply by differential pressure can be carried out more reliably.

[0091] Furthermore, once the gas supply (step ST4) is completed, the third pipe 3 will be filled with the supplied gas. If gas supply is not to be carried out subsequently, nitrogen purging of the third pipe may be performed.

[0092] In addition, in the processing performed by the control unit 9 as described above, the control unit 9 may wait for user input before executing the next step.

[0093] Furthermore, after step ST4 as described above, the control unit 9 may allow the user to choose whether or not to change the amount of gas supplied to the recipient. In this case, if the user chooses not to change the amount of gas supplied, the control unit 9 may return to step ST2 and repeat the subsequent processing.

[0094] Furthermore, the cylinder cabinet A does not necessarily have to include a control unit 9. In this case, the series of processes performed by the control unit 9 described above may be realized by operations performed by an operator from outside the cylinder cabinet A.

[0095] The embodiments and examples disclosed herein are illustrative in all respects and should be understood not to be restrictive in any way. The scope of the present invention is defined by the claims rather than the foregoing description, and all modifications within the meaning and scope equivalent to the claims are intended. [Explanation of Symbols]

[0096] 1 First piping, 2, 201, 202, 203, 204, 205 Vessel, 3 Third piping, 4 Fourth piping, 5 Fifth piping, 6a, 6b, 6c, 6d, 6e Discharge pipe, 6g, 6h Vacuum line, 7 Purge piping, 8 Measurement unit, 800 Differential pressure type liquid level detection device, 801 Low pressure side pressure guide pipe, 802 High pressure side pressure guide pipe, 9 Control unit, 10 Housing, 12 Exhaust damper, 13 Gas detector, 14 Door unit, 15 Control box, 16a, 16b Retaining chain, 17a, 17b Bracket, 18 Shelf, 41 Air intake, 42 Window, 45 Hot water chiller, 71 Display unit, 72 Power button, 73 Emergency shut-off button A Cylinder cabinet, B Liquefied gas container, C, CP1, CP2, CP3, CPC coupler, CV1~CV7 check valve, FL filter, FP flexible hose, FV1~FV5 micro-flow control valve, NPG negative pressure gauge, P1~P3 metal pipe, PG1, PG2 pressure gauge, SV1~SV3 safety valve, V1 first valve section, V2 second valve section, VP vacuum pump, Va inlet valve.

Claims

1. A housing capable of accommodating a liquefied gas container inside, A first pipe, which includes a first end connectable to the liquefied gas container and a second end opposite to the first end, is disposed inside the housing. The second pipe is connected to the first pipe at the second end and is located inside the housing. and, A third pipe including a third end connected to the second pipe and a fourth end exposed to the outside of the housing, A first valve unit installed in the first piping is capable of switching between a closed state in which the space between the first piping and the second piping is blocked and an open state in which the space is opened, A second valve unit is installed in the third piping and is capable of a second switching mechanism that switches between a closed state in which the space between the second piping and the third piping is blocked and an open state in which the space is opened. Equipped with, The second piping includes a liquefied gas containment section capable of containing liquefied gas. A differential pressure type liquid level detection device capable of detecting the liquid level of the liquefied gas contained in the liquefied gas storage section is connected to the liquefied gas storage section. In the liquefied gas containment section, when the liquefied gas is at its maximum liquid level, 50% or more of the volume of the liquefied gas containment section is in the gas phase. Liquefied gas supply device.

2. The low-pressure side pressure guide pipe of the liquid level detection device is connected at a position that is 50% or less of the capacity of the liquefied gas containment section. The liquefied gas supply device according to claim 1.

3. The liquefied gas supply device according to claim 1, wherein the piping between the first valve section and the second end section of the first piping is made of metal pipe.

4. The liquefied gas supply device according to claim 3, wherein the distance from the first valve portion to the second end portion in the first piping is 100 mm or less.

5. The third pipe is further connected to a purge gas pipe that allows purge gas to be introduced into the third pipe. A liquefied gas supply device according to any one of claims 1 to 4.

6. The system further includes a control unit that controls the first and second switching based on the liquid level in the second pipe measured by the measuring device. A liquefied gas supply device according to any one of claims 1 to 4.

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