Patent Description:
<CIT> (<CIT>) discloses a system for supplying gas from a high-pressure tank to a fuel cell.

<CIT> discloses a fuel cell system comprises a hydrogen supply apparatus, having four hydrogen tanks connected to a common supply channel and a control unit for controlling the supply of hydrogen gas from said tanks. Tanks with abnormal behaviour can be removed. For each tank an open/close valve and a pressure sensor are foreseen.

There is a concern that a large amount of leakage may occur when the high-pressure tank is detached from the system, such as when the high-pressure tank is replaced or the like. There is demand for detachability of a high-pressure tank in which such leakage is suppressed.

The present disclosure provides a gas supply system in which the tank can be detached while suppressing trouble of leak occurrence in a more sure manner.

A gas supply system according to an embodiment of the present disclosure includes a gas consumption device, a tank, and a control device. The tank is configured to store gas to be supplied to the gas consumption device, and is configured to be detachably attached from the gas consumption device. The gas consumption device includes a supply channel configured such that the gas flows through the supply channel, and a pressure sensor configured to obtain in-channel pressure of the supply channel. The tank is configured to be connected to the supply channel, and is provided with an open/close valve at a portion where the tank is connected to the supply channel. The control device is configured such that, when the tank is detached from the gas consumption device, the control device closes the open/close valve to stop supply of gas from the tank, stops consumption of the gas by the gas consumption device after the gas in the supply channel is consumed, and the control device is further configured such that it permits detachment of the tank when the pressure rise is no greater than a predetermined threshold value.

The gas consumption device may include a locking member that is configured to restrict detachment of the tank from the gas consumption device. The control device may be configured to perform operations to release restriction by the locking member when the detachment of the tank is permitted.

The open/close valve may be a check valve. The gas consumption device may include a push rod. The check valve may be configured to open by the push rod pressing the check valve, and to close by the push rod releasing pressing of the check valve. The control device may be configured to perform operations of the push rod such that the check valve is in a closed state when the tank is detached.

The open/close valve of the tank may be configured to be a solenoid valve.

The control device may be configured to output a result to be externally notified when a computation result that does not permit the detachment of the tank is obtained.

The gas supply system may include a receiver that receives the result to be externally notified and performs notification.

When a value of the pressure sensor on the supply channel rises after the gas supply from the tank is stopped, the open/close valve is conceivably malfunctioning, and there is concern about leakage. Accordingly, obtaining the value of the pressure sensor enables the state of the open/close valve to be checked in advance, and the tank can be removed (detached) in a state with leakage suppressed.

<FIG> conceptually illustrates a configuration of a gas supply system <NUM> according to an embodiment. Such a gas supply system <NUM> has a tank <NUM> that is a supply source of gas, a gas consumption device <NUM> that is a supply destination to which to supply gas from the tank <NUM>, a control device <NUM>, and a notification device <NUM>. The gas supply system <NUM> according to the present embodiment is a system that supplies hydrogen stored in the tank <NUM> to a fuel cell <NUM> included in the gas consumption device <NUM> to generate electricity. Further, in the present embodiment, the tank <NUM> is configured to be detachably attached to the gas consumption device <NUM>. This will be described in detail below.

The tank <NUM> is a container for storing gas to be supplied (hydrogen in the present embodiment) in a liquid state or a gaseous state. <FIG> are diagrams for description thereof. <FIG> is an external view of the tank <NUM>. <FIG> is a sectional view taken along an axial direction of the tank <NUM>. As can be understood from these diagrams, the tank <NUM> according to the present embodiment includes a liner <NUM>, a reinforcing layer <NUM>, necks <NUM>, and an open/close valve <NUM>. Each configuration will be described below.

The liner <NUM> is a hollow member that defines internal space of the tank <NUM>, and has a cylindrical shape in the present embodiment. The liner <NUM> has a body 12a that is cylindrically formed with a substantially constant diameter, openings at both ends of the body 12a are narrowed by side end portions 12b that are dome-shaped, and necks <NUM> are disposed at openings 12c that are narrowed. It is sufficient for the liner <NUM> to be made of a material that can hold that which is contained in the internal space thereof (e.g., hydrogen) without leaking, and various types of materials can be used. Specifically, examples of materials for the liner <NUM> include nylon resins, polyethylene-based synthetic resins, metals such as stainless steel, aluminum, and so forth. From the viewpoint of reducing the weight of the tank, the material making up the liner <NUM> is preferably a synthetic resin. The thickness of the liner <NUM> is preferably <NUM> to <NUM>, although not limited thereto in particular.

The reinforcing layer <NUM> has a plurality of layers of laminated fibers, and resin with which the fibers are impregnated, and which is cured. The fiber layers are made up of a fiber bundle wound around an outer periphery of the liner <NUM> in a plurality of layers to a predetermined thickness. The thickness of the reinforcing layer <NUM> and the number of turns of the fiber bundle are not limited in particular, since these are determined by the required strength of the reinforcing layer <NUM>, but the thickness thereof is around <NUM> to <NUM>.

Carbon fibers, for example, are used for the fiber bundle of the reinforcing layer <NUM>. The fiber bundle is formed by bundling carbon fibers, and has a band-like shape with a predetermined cross-sectional shape (e.g., a rectangular cross-section). The cross-sectional shape of the fiber bundle may be a rectangle with a width of around <NUM> to <NUM>, and a thickness of around <NUM> to <NUM>, although not limited thereto in particular. An example of the amount of carbon fibers included in the fiber bundle is around <NUM>,<NUM> carbon fibers, although the fiber bundle is not limited thereto in particular.

The resin with which the fibers (fiber bundle) are impregnated and cured in the reinforcing layer <NUM> is not limited in particular, as long as the strength of the fibers can be increased. Examples of such resins include thermosetting resins that are cured by heat, specific examples thereof including epoxy resins containing amine-based or anhydride-based curing accelerators and rubber-based reinforcing agents, unsaturated polyester resins, and so forth. In addition, another example is a resin composition having an epoxy resin as a main agent, which is cured by a curing agent being mixed therein. In this case, the resin composition, which is a mixture, is allowed to reach and permeate the fiber layer during a period following the main agent and the curing agent being mixed and before curing occurs. The mixture is automatically cured by mixing the main agent and the curing agent.

A protective layer may be disposed on an outer periphery of the reinforcing layer <NUM> as necessary. The protective layer is formed, for example, by impregnating glass fibers wound about the reinforcing layer <NUM> with a resin. The impregnating resin can be thought of as being similar to that of the reinforcing layer <NUM>. Impact resistance can be imparted to the tank <NUM> by the protective layer. The thickness of the protective layer can be around <NUM> to <NUM>, although not limited thereto in particular.

The necks <NUM> are members attached to each of the two openings 12c of the liner <NUM>. The necks <NUM> are respectively disposed at both ends of the liner <NUM> in a direction of an axis O. The necks <NUM> function as openings for communicating between the inside and outside of the tank <NUM>, and the open/close valve <NUM> is attached to one of the necks <NUM>. Accordingly, this neck <NUM> is provided with a hole having a circular cross section in which the open/close valve <NUM> is disposed. An inner face of the hole has a female screw thread corresponding to a male screw thread of the open/close valve <NUM>. The open/close valve <NUM> is fixed to the neck <NUM> by combining this female screw thread with the male screw thread of the open/close valve <NUM>. Also, the inner face of the hole has a sealing face which is a smooth surface on the inner side of the tank (high pressure side) from the female screw thread. A seal member provided on an outer periphery of the open/close valve <NUM> comes into contact with this seal surface, to realize airtightness (sealing) of inside of the tank <NUM>.

The members making up the necks <NUM> are not limited in particular, as long as required strength is obtained, and examples thereof include copper, iron, aluminum, and so forth.

The open/close valve <NUM> is held in the hole of the neck <NUM> so as to bridge the inside and outside of the tank <NUM>. The open/close valve <NUM> is disposed on one of the two necks <NUM> provided at both ends of the tank <NUM> in a longitudinal direction. Note that a plug 14a is disposed and sealed in the neck <NUM> on the other side. <FIG> is a diagram including the vicinity of the open/close valve <NUM> in <FIG>, and is a diagram illustrating a state in which the open/close valve <NUM>, and a connecting device <NUM> of the gas consumption device <NUM> to be described later, are separated. The open/close valve <NUM> has a shaft portion to be disposed inside the hole of the neck <NUM>. An outer peripheral face of the shaft portion is provided with a male screw thread that is combined with a female screw thread of the neck <NUM>. The open/close valve <NUM> is fixed to the hole of the neck <NUM> by combining the female screw thread with the male screw thread. Also, a sealing member (omitted from illustration) is disposed on the outer peripheral face of the open/close valve <NUM>. This sealing member is disposed so as to come into contact with the sealing face on the inner face of the hole of the neck <NUM> to realize airtightness (sealing).

The open/close valve <NUM> has a valve element <NUM> and a connecting portion <NUM>.

The valve element <NUM> is a switching valve that permits and restricts communication between the inside and outside of the tank <NUM>. A check valve is applied as the valve element <NUM> in the present embodiment. Accordingly, in the present embodiment, the valve element <NUM> is biased so as to restrict the communication when the valve is closed, and pressing the valve element <NUM> against the biasing force moves the valve element <NUM>, and the communication is permitted. Thus, according to the present embodiment, pressing and releasing pressing of the valve element <NUM> switches communication between the inside and the outside of the tank <NUM>, and accordingly means for pressing the valve element <NUM> are necessary. Accordingly, the gas consumption device <NUM> is provided with means (a push rod <NUM>) for pressing the valve element <NUM>, which will be described later. By using a check valve as the valve element <NUM>, and performing opening/closing thereof at the side of the gas consumption device <NUM>, there is no need to electrically connect the tank <NUM> that is detachably attached to the gas consumption device <NUM> to the control device <NUM> for control, and control by the control device <NUM> can be performed in a more sure manner.

Thus, an example in which a check valve is applied as the valve element <NUM> is shown in the present embodiment, but this is not limiting as long as communication between the inside and outside of the tank <NUM> can be permitted and restricted, and a solenoid valve can be applied as the valve element. Using a solenoid valve enables the opening/closing to be directly controlled by the control device <NUM> without using pressing means.

The open/close valve <NUM> has the connecting portion <NUM> connected to the gas consumption device <NUM>, on the side thereof that is connected to the gas consumption device <NUM>. The connecting portion <NUM> is a part that enables engaging and detaching of the connecting portion <NUM> and the connecting portion <NUM> of the connecting device <NUM> of the gas consumption device <NUM>. Although specific forms thereof are not limited, a mechanical coupling (mechanical interface) can be given in the present embodiment. Among these, a mount such as that for connecting a photography lens to a main body of a camera can be applied. More specifically, a C-mount can be used. Note that in the present embodiment, the gas consumption device <NUM> is provided with a locking member <NUM>, which will be described later. A configuration is made such that operation of the locking member <NUM> disables detaching of the connecting portion <NUM> and the gas consumption device <NUM>. Also, a configuration is made such that releasing the locking member <NUM> enables detaching of the connecting portion <NUM> and the gas consumption device <NUM>.

Allowable pressure of the tank <NUM> is not limited in particular. The tank <NUM> may be a tank capable of storing hydrogen at an allowable pressure of more than <NUM> MPa to <NUM> MPa or less from the viewpoint of capability of supplying a greater amount of hydrogen. The present embodiment enables leakage to be averted in a more sure manner at the time of detachment, even with such high-pressure tanks.

In the present embodiment, a plurality (e.g., three) of the tanks <NUM> is provided, and each tank <NUM> is filled with hydrogen. An example in which three tanks <NUM> are disposed is given here. The three tanks are denoted by respective signs 11a, 11b, and 11c, for distinguishing thereamong. In the present embodiment, the three tanks 11a, 11b, and 11c may be collectively referred to as "tank <NUM>" or "tanks <NUM>". These tanks 11a, 11b, and 11c may all have the same capacity, or may include tanks with different capacities.

The gas consumption device <NUM> is the gas supply destination of the tank <NUM>, and is a device that receives and consumes gas. In the present embodiment, the gas consumption device <NUM> includes the fuel cell <NUM>, a supply channel <NUM>, the connecting devices <NUM>, an injector <NUM>, and pressure gauges <NUM>, as illustrated in <FIG>.

The fuel cell <NUM> is equipment that consumes gas supplied thereto, and receives supply of hydrogen from the tank <NUM> and also receives supply of air from an air inlet (omitted from illustration) to generate electricity. The specific configuration of the fuel cell <NUM> is not limited in particular, and various configurations can be used.

The supply channel <NUM> is a route for guiding gas from the tank <NUM> to the fuel cell <NUM>, and is made up of pipes. In the present embodiment, each of the tanks 11a, 11b, and 11c and the fuel cell <NUM> are connected. Here, pipes 22a, 22b, and 22c extending from the tanks 11a, 11b, and 11c, respectively, join to form one pipe 22d, which is connected to the fuel cell <NUM>.

The connecting device <NUM> is disposed on the supply channel <NUM>, at a connecting portion between the supply channel <NUM> and the tank <NUM>. The connecting device <NUM> is connected to the connecting portion <NUM> provided in the open/close valve <NUM> of the tank <NUM> and operates to open and close the valve element <NUM> (check valve) of the tank <NUM>. <FIG> is a diagram including the vicinity of the connecting device <NUM> in <FIG>, and is a diagram illustrating a state in which the open/close valve <NUM>, and the connecting device <NUM> of the gas consumption device <NUM> are separated. As can be understood from <FIG>, the connecting device <NUM> has a cylindrical body 23a, the push rod <NUM> disposed inside the cylindrical body 23a, the connecting portion <NUM> provided at a distal end of the cylindrical body 23a, and the locking member <NUM>.

The push rod <NUM> is a member that is capable of pressing the valve element <NUM> provided in the open/close valve <NUM> of the tank <NUM>. In the present embodiment, the push rod <NUM> is rod-shaped, and is capable of pressing the valve element <NUM> with a distal end thereof. Accordingly, as can be understood from <FIG>, the push rod <NUM> is disposed inside the cylindrical body 23a, and is configured to be capable of moving in the axial direction of the push rod <NUM> as indicated by a straight arrow in <FIG>, so as to project from and withdraw into the cylindrical body 23a.

The connecting portion <NUM> is provided at the end of the cylindrical body 23a, on the side thereof facing the connecting portion <NUM> provided to the open/close valve <NUM>. The connecting portion <NUM> can be engaged with and detached from the connecting portion <NUM>, as described above. Specifically, in the present embodiment, a mechanical coupling (mechanical interface) can be given. Among these, a mount such as that for connecting a photography lens to a main body of a camera can be applied. More specifically, a C-mount can be used.

The locking member <NUM> is a member that restricts release of the engagement between the connecting portion <NUM> and the connecting portion <NUM> when engaged, i.e., such that detachment of the open/close valve <NUM> and the connecting device <NUM> cannot be performed. The specific form of the locking member <NUM> is not limited in particular, but the locking member <NUM> can be configured such that the locking member <NUM> that is rod-shaped can project from and withdraw into the cylindrical body 23a, as illustrated in <FIG>, for example. The locking member <NUM> projects from the cylindrical body 23a and enters the connecting portion <NUM>, thereby restricting the connecting portion <NUM> and the connecting portion <NUM> so as not to be capable of being detached. When the locking member <NUM> is withdrawn into the cylindrical body 23a and retracted from the connecting portion <NUM>, the connecting portion <NUM> and the connecting portion <NUM> can be detached.

The injector <NUM> is disposed on the supply channel <NUM> (the supply channel 22d in the present embodiment), between the connecting device <NUM> and the fuel cell <NUM>, and controls the supply of hydrogen to the fuel cell <NUM>. Although specific form of the injector is not limited in particular, a flow control valve can be given.

The pressure gauges <NUM> are pressure gauges that measure in-channel pressure of the supply channel <NUM> (the pressure inside the pipes) between the connecting devices <NUM> and the injector <NUM>. Although the specific form of the pressure gauges <NUM> is not limited in particular in the present embodiment, a configuration is made to transmit pressure value data that is obtained to the control device <NUM>.

At the time of detaching the tank <NUM>, the control device <NUM> determines whether the tank <NUM> can be detached. The control device <NUM> is a control device that performs operations so as to place the tank <NUM> in a detachable state when determination is made that the tank <NUM> can be detached, and when determination is made that the tank <NUM> cannot be detached, performs output for notification thereof. Accordingly, in the present embodiment, the control device <NUM> is configured to be capable of communication with the push rods <NUM> and the locking members <NUM> of the connecting devices <NUM>, the injector <NUM>, the pressure gauges <NUM>, and the notification device <NUM>.

As conceptually illustrated in <FIG>, the control device <NUM> includes a central processing unit (CPU) <NUM> that is a processor and that performs computation, random-access memory (RAM) <NUM> that functions as a work area, read-only memory (ROM) <NUM> that functions as a recording medium, a reception unit <NUM> that is an interface through which the control device <NUM> receives information either wired or wirelessly, and a transmission unit <NUM> that is an interface through which the control device <NUM> externally sends information either wired or wirelessly. Accordingly, the control device <NUM> is configured such that the pressure gauges <NUM> are connected to the reception unit <NUM> and information is received therefrom. The control device <NUM> is configured such that the push rods <NUM>, the locking members <NUM>, the injector <NUM>, and the notification device <NUM> are connected to the transmission unit <NUM> such that signals for operation thereof can be transmitted thereto.

Saved in the control device <NUM> is a program that, at the time of detaching the tank <NUM>, determines whether the tank <NUM> can be detached, performs computational processing for operating each piece of equipment in accordance with the determination regarding whether detachment can be performed, and transmits signals for operation to each piece of equipment. In the control device <NUM>, the CPU <NUM>, the RAM <NUM>, and the ROM <NUM> that serve as hardware resources operate cooperatively with the program. Specifically, the CPU <NUM> performs desired control by executing a computer program recorded in the ROM <NUM> in the RAM <NUM> that functions as a work area. Information that is acquired or generated by the CPU <NUM> is stored in the RAM <NUM>. Further, a separate recording medium may be provided within the control device <NUM>, or externally therefrom, and programs and various types of data may be recorded therein. Specific contents of control will be described later.

Such a control device <NUM> can typically be made up of a computer.

The notification device <NUM> is a device that, at the time of detachment of the tank <NUM>, performs notification when the control device <NUM> determines that the tank <NUM> cannot be detached. Accordingly, the notification device <NUM> functions as a receiver for receiving a signal from the control device <NUM>, which is a transmitter of the signal of this notification, and also performs specific notification. The notification method is not limited in particular, and may include any of an image display, a warning sound, sound, and light, or a combination of at least two or more of these. For example, an image display device can be used for the image display, a speaker can be used for the warning sound or the sound, and a lighting device can be used for the light.

The control that is performed when the tank <NUM> is detached in the gas supply system <NUM> will be described below.

Prior to the detachment of the tank <NUM>, hydrogen flows out from the tank <NUM> and is supplied to the fuel cell <NUM> over the supply channel <NUM>. Electricity is generated at the fuel cell <NUM>. At this time, the tank <NUM> is in a state of being connected to the gas consumption device <NUM>, and the valve element <NUM> is open. <FIG> illustrates such a connection state between the tank <NUM> and the gas consumption device <NUM>. <FIG> is a cross-section from the same perspective as in <FIG>.

As can be understood from <FIG>, when the tank <NUM> is connected to the gas consumption device <NUM> and is in a gas supplying state, the connecting portion <NUM> provided to the open/close valve <NUM> of the tank <NUM>, and the connecting portion <NUM> provided to the connecting device <NUM> of the gas consumption device <NUM>, are engaged. Also, at this time, the locking member <NUM> projects from the cylindrical body 23a and enters the connecting portion <NUM>, thereby realizing a locked state. Further, the push rod <NUM> projects from the cylindrical body 23a and the distal end of the push rod <NUM> reaches the inner side of the open/close valve <NUM>, thereby pressing the valve element <NUM>. Thus, the open/close valve <NUM> is in an open state.

<FIG> shows a flow of tank detachment control S10 according to an embodiment. As can be understood from <FIG>, the tank detachment control S10 includes processes S11 to S19. Each of these processes proceeds in accordance with a program stored in the control device <NUM>, and each piece of equipment is operated according to commands from the control device <NUM>. Each process will be described below.

In a process of starting detachment (S11), the control device <NUM> receives a signal that triggers the start of tank detachment. As a result, detachment of the tank <NUM> starts, and the tank detachment control S10 is performed. The signal that triggers the start of tank detachment is not limited in particular. A user may operate a detachment start switch (omitted from illustration) that is provided, or a signal may be emitted when the volume within the tank <NUM> decreases and falls below a predetermined pressure.

In a process of closing the open/close valve (S12), the control device <NUM> closes the open/close valve <NUM> in response to a signal for closing that is received in process S11. Specifically, the control device <NUM> closes the valve element <NUM> by moving the push rod <NUM> to release the pressing on the valve element <NUM>. However, as illustrated in <FIG>, the state in which the push rod <NUM> remains inside the open/close valve <NUM> while projecting from the cylindrical body 23a is maintained. Thus, the open/close valve <NUM> and the connecting device <NUM> are maintained in a state of communicating (however, the valve is closed, and accordingly communication with the inside of the tank is shut off) and sealing performance are maintained, and airtightness of the supply channel <NUM> is secured. This operation is performed for all the tanks <NUM> when multiple tanks <NUM> are disposed.

In a process of injection operations (S13), the control device <NUM> operates the injector <NUM> to feed the hydrogen present in the channel of the supply channel <NUM> to the fuel cell <NUM>. This causes the fuel cell <NUM> to generate electricity and to consume the hydrogen in the channel of the supply channel <NUM>. The open/close valve <NUM> of the tank <NUM> is closed in process S12. Accordingly, no new gas is supplied from the tank <NUM> in a normal state, and the gas in the channel of the supply channel <NUM> is consumed in this process S13, whereby the pressure in the channel drops. The electricity obtained in this process S13 can be used to charge a secondary battery that is omitted from illustration, but is not limited to this in particular.

In a process of stopping injection (S14), the control device <NUM> stops the injector <NUM>, after waiting for the gas in the channel of the supply channel <NUM> to be consumed in process S13. Accordingly, the inside of the supply channel <NUM> between the connecting device <NUM> and the injector <NUM> is shut off. The timing of stopping the injector <NUM> is not limited in particular, as long as a state can be obtained in which the hydrogen in the channel of the supply channel <NUM> is consumed to some extent and the pressure in the channel is reduced. For example, this process S14 can be performed after the control device <NUM> confirms that a predetermined amount of time elapsing after the injector <NUM> was operated in process S13, a certain amount of electricity being generated by the fuel cell <NUM> after the injector <NUM> is operated in process S13, or a value of the pressure gauge <NUM> acquired after the injector <NUM> is operated decreasing to a value lower than the pressure within the tank <NUM>.

In a process of obtaining change in pressure value over time (S15), the control device <NUM> obtains the value of the pressure gauge <NUM> in time series, to obtain change in the pressure value. Thus, change in the in-channel pressure of the supply channel <NUM> shut off in process S14 is obtained.

In a process of pressure rise determination (S16), the control device <NUM> determines whether the pressure change obtained in process S15 is within a predetermined rising amount (threshold value) or less. When the pressure rise is within the predetermined amount, there is no problem with the sealing performance of the valve element <NUM> of the open/close valve <NUM> of the tank <NUM>. Also, the hydrogen in the channel of the supply channel <NUM> is consumed in process S13, and accordingly hydrogen will not leak and not cause trouble even when the tank <NUM> is detached. Therefore, determination of Yes is made, and the flow advances to process S17. On the other hand, when the pressure rise exceeds the predetermined amount, there is a possibility that there is a problem with the sealing performance of the valve element <NUM> of the open/close valve <NUM>. Also, hydrogen is in the channel of the supply channel <NUM>, and accordingly hydrogen may leak to the surroundings when the tank <NUM> is detached, causing trouble. Therefore, determination of No is made, and the flow advances to process S18.

When determination of Yes is made in process S16, the flow advances to process S17. The control device <NUM> causes the push rod <NUM> to retreat, to detach the entire push rod <NUM> from the inside of the open/close valve <NUM>, as illustrated in <FIG>. Further, the control device <NUM> also causes the locking member <NUM> to retreat, such that the entire locking member <NUM> is retracted from the connecting portion <NUM>. Thus, the tank <NUM> and the connecting device <NUM> can be detached. In the present embodiment, the tank <NUM> and the connecting device <NUM> are engaged by a C-mount. Accordingly, for example, a person who detaches the tank <NUM> may rotate the tank <NUM> and the connecting device <NUM> relative to each other to detach the tank <NUM>, or the control device <NUM> may rotate the tank <NUM> and the connecting device <NUM> relative to each other to detach the tank <NUM>.

When determination of No is made in process S16, the flow advances to process S18, and the push rod <NUM> and the locking member <NUM> are maintained in the state of process S12 (<FIG>). The flow then advances to process S19, and the notification device <NUM> makes notification thereof in accordance with to a command from the control device <NUM>.

Claim 1:
A gas supply system (<NUM>) comprising:
a gas consumption device (<NUM>);
a tank (<NUM>) that stores gas to be supplied to the gas consumption device (<NUM>), and that is configured to be detachably attached to the gas consumption device (<NUM>); and
a control device (<NUM>), wherein
the gas consumption device (<NUM>) includes a supply channel (<NUM>) configured such that the gas flows through the supply channel (<NUM>), and a pressure sensor (<NUM>) configured to obtain in-channel pressure of the supply channel (<NUM>),
the tank (<NUM>) is configured to be connected to the supply channel (<NUM>), and is provided with an open/close valve (<NUM>) at a portion where the tank (<NUM>) is connected to the supply channel (<NUM>), and
the control device (<NUM>) is configured such that, when the tank (<NUM>) is detached from the gas consumption device (<NUM>), the control device (<NUM>) closes the open/close valve (<NUM>) to stop supply of gas from the tank (<NUM>), stops consumption of the gas by the gas consumption device (<NUM>) after the gas in the supply channel (<NUM>) is consumed, and the control device is further configured such that it permits detachment of the tank when the pressure rise is no greater than a predetermined threshold value.