Gas supply system

Claim 2

In a gas supply system having a plurality of banks of storage containers which store gas at dIfferent pressures and are all connected to a common outlet, means for withdrawing pressurized gas through said outlet first from the bank which is at the lowest pressure, and automatically operable means for withdrawing pressurized gas through said outlet from a second, higher pressure bank of storage containers following its withdrawal from said lowest pressure bank, said automatically operable means comprising a normally closed valve between said higher pressure bank of storage containers and said outlet, and means for opening said valve in response to a pressure drop in said lowest pressure bank to initiate the withdrawal of gas from said higher pressure bank after a time period following the initial withdrawal of gas from said lowest pressure bank, the improvement wherein said last mentioned means comprises: means providing a flow restriction between said lowest pressure bank and said outlet; a differential pressure switch connected across said flow restriction to sense the flow therethrough; and means responsive to the operation of said differential pressure switch when the flow through said restriction substantially ceases for opening said valve between said higher pressure bank and said outlet.

Claim 3

A gas supply system according to claim 1, wherein said valve is a solenoid valve having an operating coil in circuit with said differential pressure switch to have its energization controlled thereby, and said differential pressure switch is normally closed and is opened during the flow of gas from said lowest pressure bank through said flow restriction.

Claim 4

A gas supply system according to claim 2, and further comprising a check valve between said flow restriction and said outlet for preventing the flow of gas from said higher pressure bank into said lowest pressure bank.

Claim 5

A gas supply system according to claim 3, and further comprising: power supply means in circuit with said operating coil and said differential pressure switch; and means in said circuit and operable following the initiation of a demand for gas from said outlet to disconnect said differential pressure switch from said power supply long enough for said switch to open in response to the flow of gas through said flow restriction, and operable thereafter to connect said differential pressure switch to said power supply.

Claim 6

A gas supply system according to claim 4, wherein said last-mentioned means comprises a normally-open time delay switch in series with said differential pressure switch and said operating coil across said power supply, said time delay switch being operable to close after a time delay in response to the initiation of a demand for gas from said outlet.

Claim 7

A gas supply system according to claim 4, wherein said plurality of banks of storage containers includes a third bank which stores gas at a higher pressure than said second bank, and further comprising: means providing a second flow restriction between said second bank of storage containers and said outlet; a second differential pressure switch connected across said second flow restriction to sense the gas flow therethrough, said second differential pressure switch being normally closed and being opened during the flow of gas through said second flow restriction; a normally closed second solenoid valve connected between said third bank of storage containers and said outlet and having an operating coil connected to said power supply through said second differential pressure switch: means operable following the cessation of gas flow from said lowest pressure bank to said outlet for disconnecting said second differential pressure switch from said power supply long enough for said last-mentioned switch to open in response to the flow of gas through said second flow restriction, and operable thereafter to connect said second differential pressure switch to said power supply; and a check valve between said second flow restriction and said outlet for preventing the flow oF gas from said third bank of storage containers into said second bank of storage containers.

Claim 8

In a gas supply system having a plurality of banks of storage containers which store gas at different pressures and are all connected to a common outlet; means for withdrawing pressurized gas through said outlet first from the bank which is at the lowest pressure; automatically operable means for withdrawing pressurized gas through said outlet from a second, higher pressure bank of storage containers following its withdrawal from said lowest pressure bank, said automatically operable means comprising a normally-closed valve between said higher pressure bank of storage containers and said outlet, and means for opening said valve to initiate the withdrawal of gas from said higher pressure bank after a time period following the initial withdrawal of gas from said lowest pressure bank; and a check valve between said lowest pressure bank and said outlet for preventing gas that is being withdrawn from the higher pressure bank from flowing into said lowest pressure bank; the improvement wherein: said normally-closed valve is a solenoid valve which opens when its operating coil is energized; and said means for opening said solenoid valve comprises a time delay switch in circuit with the operating coil of said solenoid valve, said time delay switch being operable to remain open for a predetermined time period following the initial withdrawal of gas from said lowest pressure bank, and then closing to complete the energization circuit for the operating coil of said solenoid valve.

Claim 9

In a gas supply system having a plurality of banks of storage containers which store gas at different pressures and are all connected to a common outlet; means for withdrawing pressurized gas through said outlet first from the bank which is at the lowest pressure; automatically operable means for withdrawing pressurized gas through said outlet from a second, higher pressure bank of storage containers following its withdrawal from said lowest pressure bank, said automatically operable means comprising a normally-closed valve between said higher pressure bank of storage containers and said outlet, and means for opening said valve to initiate the withdrawal of gas from said higher pressure bank after a time period following the initial withdrawal of gas from said lowest pressure bank; and a check valve between said lowest pressure bank and said outlet for preventing gas that is being withdrawn from the higher pressure bank from flowing into said lowest pressure bank; the improvement wherein: said normally-closed valve is a solenoid valve which opens when its operating coil is energized; and said means for opening said solenoid valve comprises a time delay switch in circuit with the operating coil of said solenoid valve, said time delay switch being operable to remain open for a predetermined time period following the initial withdrawal of gas from said lowest pressure bank, and then closing to complete the energization circuit for the operating coil of said solenoid valve.

Claim 10

A gas supply system according to claim 7, wherein said plurality of banks of storage containers include a third bank which store gas at a higher pressure than said second bank, and further comprising: a second normally-closed solenoid valve connected between third bank of storage containers and said outlet and operable to open when its operating coil is energized: a second time delay switch in circuit with the operating coil of said second solenoid valve, said second time delay switch being operable to remain open for a predetermined time period following the initial withdrawal of gas from said second bank of storage containers, and then closing to complete the energization circuit for the operating coil of said second solenoid valve; and a check valve between said second bank and said outlet for preventing gas that is being withdrawn from said third bank of storage containers from flowing into said second bank.

Claim 11

In a system for withdrawing pressurized gas from a storage source, the improvement which comprises: an electrically operated utilization valve connected to receive pressurized gas from said source; a plurality of pressure switches having individual electrical connections to said valve to control its operation, each of said pressure switches being operably connected to sense the gas pressure at the outlet side of said valve and being operable to open at different maximum pressures, respectively; and manually operated means for selectively connecting said pressure switches individually in circuit with said valve to maintain the latter open until the gas pressure at its outlet side reaches the pressure for which the selected pressure switch is set to open and then to close said valve.

Claim 12

In a system for withdrawing pressurized gas from a storage source, the improvement which comprises: an electrically operated utilization valve connected to receive pressurized gas from said source; a plurality of pressure switches having individual electrical connections to said valve to control its operation, each of said pressure switches being operably connected to sense the gas pressure at the outlet side of said valve and being operable to open at different maximum pressures, respectively; and manually operated means for selectively connecting said pressure switches individually in circuit with said valve to maintain the latter open until the gas pressure at its outlet side reaches the pressure for which the selected pressure switch is set to open and then to close said valve.

Claim 13

In a system for withdrawing pressurized gas from a storage source, the improvement which comprises: an electrically operated utilization valve connected to receive pressurized gas from said source; a presure gauge operatively connected to the outlet side of said valve to sense the gas pressure thereat, an actuator operatively coupled to said gauge to move in accordance with said gas-pressure; and a normally closed switch adjustably mounted at said actuator to be engagd and opened by the latter when the gauge reaches the pressure reading corresponding to the selected maximum pressure, said switch when opened Being operable to close said valve.

Claim 14

In a system for withdrawing pressurized gas from a storage source, the improvement which comprises: an electrically operated utilization valve connected to receive pressurized gas from said source; a presure gauge operatively connected to the outlet side of said valve to sense the gas pressure thereat, an actuator operatively coupled to said gauge to move in accordance with said gas-pressure; and a normally closed switch adjustably mounted at said actuator to be engagd and opened by the latter when the gauge reaches the pressure reading corresponding to the selected maximum pressure, said switch when opened Being operable to close said valve.

Claim 15

In a supply system having a plurality of banks of storage containers which store gas at different pressures and are all connected to a common outlet, the improvement which comprises: a utilization valve connected to said outlet to receive pressurized gas therethrough first from the bank of storage containers which is at the lowest pressure; means controlling the opening and closing of said utilization valve and including switch means for selecting the maximum gas pressure to be permitted at the outlet side of said valve, said switch means being operable in response to the gas pressure at the outlet side of said valve to close said valve when the selected maximum pressure is reached; and automatically operable means for passing pressurized gas to said outlet from one or more successively higher pressure banks of the storage containers following its withdrawal from said lowest pressure bank.

Claim 16

In a supply system having a plurality of banks of storage containers which store gas at different pressures and are all connected to a common outlet, the improvement which comprises: a utilization valve connected to said outlet to receive pressurized gas therethrough first from the bank of storage containers which is at the lowest pressure; means controlling the opening and closing of said utilization valve and including switch means for selecting the maximum gas pressure to be permitted at the outlet side of said valve, said switch means being operable in response to the gas pressure at the outlet side of said valve to close said valve when the selected maximum pressure is reached; and automatically operable means for passing pressurized gas to said outlet from one or more successively higher pressure banks of the storage containers following its withdrawal from said lowest pressure bank.

Claim 17

A gas supply system according to claim 11, wherein said automatically operable means comprises: a normally-closed valve between each of said one or more higher pressure banks and said outlet; and means for opening each said last-mentioned valve to begin the withdrawal of gas from the corresponding bank after a time period following the initial withdrawal of gas from the next lower pressure bank.

Claim 18

A gas supply system according to claim 12, and further comprising a check valve between said outlet and each bank of the storage containers except the highest pressure bank for preventing gas flow from a higher pressure bank to any lower pressure bank.

Claim 19

A gas supply system according to claim 13, wherein said utilization valve is electrically operated, and said means controlling the opening and closing of said utilization valve comprises: a plurality of pressure switches having individual electrical connections to said utilization valve to control its operation, each of said pressure switches being operably connected to sense the gas pressure at the outlet side of said utilization valve and being operable to open at different pressures, respectively; and manually operated means for selectively connecting said pressure switches individually in circuit with said utilization valve to maintain the latter open until the gas pressure at its outlet side reaches the pressure for which the selected pressure switch is set to open.

Claim 20

A gas supply system according to claim 13, wherein said utilization valve is electrically operated, and said means controlling the opening and closing of said utilization valve comprises: a pressure gauge operatively connected to the outlet side of said utilization valve to sense the gas pressure thereat, an actuator operatively coupled to said gauge to move in accordance with said gas presure; and a normally closed switch adjustably mounted at said pressure gauge along the path of movement of said actuator to be engaged and opened by the latter when the gauge reaches the pressure reading corresponding to the selected maximum pressure.