Pneumatically-operated gas demand apparatus

• US 5,666,945 A
• Filed: 06/07/1995
• Issued: 09/16/1997
• Est. Priority Date: 06/07/1995
• Status: Expired due to Fees

• Current Assignee: Salter Labs
• Original Assignee: Salter Labs
• Inventors: Davenport, James M.
• Primary Examiner(s): Lewis, Aaron J.
• Application Number:
  US08/488,202
• Time in Patent Office: 832 Days
• Field of Search: 128/204.26, 128/204.23, 128/205.24, 128/200.14, 128/203.12, 128/207.18
• US Class Current: 128/200.14
• CPC Class Codes: A61M 11/06 of the injector type
• CPC Class Codes: A61M 16/0677 Gas-saving devices therefor
• CPC Class Codes: A61M 16/20 Valves specially adapted to medical respiratory devices
• CPC Class Codes: A61M 16/207 Membrane valves with pneumatic amplification stage, i.e. having master and slave membranes
• CPC Class Codes: A61M 2016/0021 with a proportional output signal, e.g. from a thermistor

Abstract

A pneumatically-operated gas demand apparatus coupled in interruptible fluid communication between a recipient and a first source of a pressurized first gas controls delivery of the first gas to the recipient as the recipient inhales and exhales and comprises a supply valve and a sensing valve. The supply valve has a first interior chamber divided by a flexible first diaphragm into a supply chamber region and a control chamber region. The supply chamber region is in interruptible fluid communication between the first source of the first gas and the recipient. The control chamber region is in continuous fluid communication with a second source of a pressurized second gas. The sensing valve has a second interior chamber divided by a flexible second diaphragm into a venting chamber region and a sensing chamber region. The venting chamber region is in interruptible fluid communication between the control chamber region and an ambient air environment. The sensing chamber region is in continuous fluid communication with the recipient. When the recipient inhales, the second diaphragm moves to a flow-causing position to cause the second gas to flow into the ambient air environment and causes the first diaphragm to move to a flow-supplying position thereby delivering the first gas to the recipient. When the recipient exhales, the second diaphragm moves to a flow-stopping position to prevent the second gas to flow into the ambient air environment and causes the first diaphragm to move to a flow-blocking position thereby preventing delivery of the first gas to the recipient.

Claims

1. In combination with a nebulizer for producing a medicament-containing aerosol and a source of pressurized gas, an intermittent gas delivery device disposed between and in intermittent fluid communication with the nebulizer and the source of pressurized gas, comprising:

(a) a regulator mechanism in continuous fluid communication with and disposed downstream of the source of pressurized gas;

(b) a bolus chamber structure defining a bolus chamber therein and disposed downstream of and in fluid communication with said regulator mechanism;

(c) a supply orifice element having a supply orifice formed therethrough, said supply orifice element disposed between said regulator mechanism and said bolus chamber, said supply orifice providing fluid communication between said regulator mechanism and said bolus chamber; and

(d) a supply valve in downstream fluid communication with said supply orifice and operative to move between a flow-blocking position whereby the pressurized gas is prevented from flowing from the source to the nebulizer and a flow-supplying position whereby the pressurized gas flows from the source to the nebulizer such that a high flow pulse of pressurized gas first generates a fine-mist plume of the medicament-containing aerosol in the nebulizer and subsequently a steady state flow of pressurized gas continues to produce the fine-mist plume of the medicament-containing aerosol in the nebulizer until said supply valves moves to the flow-blocking position.

2. An intermittent gas delivery device according to claim 1 including a sensing valve operably connected to said supply valve and the source of pressurized gas to cause said supply valve to move between the flow-causing and the flow-blocking positions.

3. An intermittent gas delivery device according to claim 1 including a sense tube connected in fluid communication with said supply valve and having a sense tube inlet thereinto, said sense tube operative with a finger of the recipient to be placed over a sense tube inlet 518 to cause said supply valve to be in the flow-blocking position and to be removed from said sense tube inlet to cause said supply valve to move to the flow-supplying position.

4. A pneumatically-operated gas demand apparatus according to claim 3 wherein said regulator mechanism includes a regulator housing, a flexible regulator diaphragm and a valve assembly, said regulator housing defining a regulator chamber therein, said regulator diaphragm disposed within said regulator chamber and connected to said regulator housing in a manner to divide said regulator chamber into a vented regulator chamber region in continuous fluid communication with the ambient air environment and a supply regulator chamber region in interruptible fluid communication between the first source of pressurized first gas and said supply chamber region of said supply valve, said regulator diaphragm operative to hermetically seal said vented regulator chamber region and said supply regulator chamber region from one another, said valve assembly operably connected to said regulator diaphragm and disposed within said supply regulator chamber region, said valve assembly operative between a closed condition whereby an upstream portion of said supply regulator region is in fluid isolation with a downstream portion of said supply regulator region and an opened condition whereby said upstream portion of said supply regulator region is in fluid communication with said downstream portion of said supply regulator region, said valve assembly resiliently and yieldably biased against said regulator diaphragm in the closed condition, said regulator diaphragm resiliently and yieldably biased against said valve assembly in the opened condition whereby when a first gas pressure of the first gas reaches a threshold gas pressure amount in said downstream portion of said supply regulator region, said valve assembly is in the closed condition and when said first gas pressure is less than said threshold gas pressure amount, said valve assembly is in the opened condition.

5. A pneumatically-operated gas demand apparatus coupled in interruptible fluid communication between a recipient and a first source of a pressurized first gas and adapted for controlling delivery of the first gas to the recipient as the recipient inhales and exhales, comprising:

(a) a supply valve including a supply valve housing defining a first interior chamber formed therein and a flexible first diaphragm member disposed within said first interior chamber and connected to said supply valve housing in a manner to divide said first interior chamber into a supply chamber region and a control chamber region, said supply chamber region being in interruptible fluid communication with and between the first source of the first gas and the recipient, said control chamber region being in continuous fluid communication with a second source of a pressurized second gas, said first diaphragm member operative to hermetically seal said supply chamber region and said control chamber region from one another and to move between a flow-blocking position and a flow-supplying position;

(b) a sensing valve including a sensing valve housing defining a second interior chamber formed therein and a flexible second diaphragm member disposed within said second interior chamber and connected to said sensing valve housing in a manner to divide said second interior chamber into a venting chamber region and a sensing chamber region, said venting chamber region being in interruptible fluid communication with and between said control chamber region of said first interior chamber of said supply valve and an ambient air environment, said sensing chamber region being in continuous fluid communication with the recipient, said second diaphragm member operative to hermetically seal said venting chamber region and said sensing chamber region from one another and responsive when the recipient inhales and exhales to move between a flow-stopping position and a flow-causing position whereby, when the recipient inhales, said second diaphragm member is in the flow-causing position thereby causing the second gas to flow from said control chamber region, through said venting chamber region and into the ambient air environment which, in turn, causes said first diaphragm member to be in the flow-supplying position thereby delivering the first gas from the first source of pressurized first gas to the recipient and, when the recipient exhales, said second diaphragm member is in the flow-stopping position thereby preventing the second gas to flow from said control chamber region, through said venting chamber region and into the ambient air environment which, in turn, causes said first diaphragm member to be in the flow-blocking position thereby preventing delivery of the first gas to the recipient;

(c) a pilot orifice element having a pilot orifice extending therethrough, said pilot orifice element disposed between the second source of pressurized second gas and said control chamber region of said supply valve, said pilot orifice providing fluid communication between the second source of pressurized second gas and said control chamber region;

(d) a regulator mechanism disposed between and in interruptible fluid communication with the first source of the first gas and said supply chamber region of said supply valve; and

(e) a bolus chamber structure defining a bolus chamber therein and disposed between and in fluid communication with said regulator mechanism and said supply chamber region of said supply valve.

6. A pneumatically-operated gas demand apparatus according to claim 5 wherein the first gas and the second gas are the same.

7. A pneumatically-operated gas demand apparatus according to claim 6 wherein the first gas and the second gas are selected from a group of gases consisting of oxygen, nitrous oxide and air.

8. A pneumatically-operated gas demand apparatus according to claim 5 wherein the first gas and the second gas are different from each other.

9. A pneumatically-operated gas demand apparatus according to claim 8 wherein the first gas and the second gas are selected from different ones of a group consisting of oxygen, nitrous oxide and air.

10. A pneumatically-operated gas demand apparatus according to claim 5 including a supply orifice element having a supply orifice formed therethrough, said supply orifice element disposed between said regulator mechanism and said bolus chamber, said supply orifice providing fluid communication between said regulator mechanism and said bolus chamber.

11. A pneumatically-operated gas demand apparatus coupled in interruptible fluid communication between a recipient and a first source of a pressurized first gas and adapted for controlling delivery of the first gas to the recipient as the recipient inhales and exhales, comprising:

(a) a supply valve including a supply valve housing defining a first interior chamber formed therein and a flexible first diaphragm member disposed within said first interior chamber and connected to said supply valve housing in a manner to divide said first interior chamber into a supply chamber region and a control chamber region, said supply chamber region being in interruptible fluid communication with and between the first source of the first gas and the recipient, said control chamber region being in continuous fluid communication with a second source of a pressurized second gas, said first diaphragm member operative to hermetically seal said supply chamber region and said control chamber region from one another and to move between a flow-blocking position and a flow-supplying position;

(b) a sensing valve including a sensing valve housing defining a second interior chamber formed therein and a flexible second diaphragm member disposed within said second interior chamber and connected to said sensing valve housing in a manner to divide said second interior chamber into a venting chamber region and a sensing chamber region, said venting chamber region being in interruptible fluid communication with and between said control chamber region of said first interior chamber of said supply valve and an ambient air environment, said sensing chamber region being in continuous fluid communication with the recipient, said second diaphragm member operative to hermetically seal said venting chamber region and said sensing chamber region from one another and responsive when the recipient inhales and exhales to move between a flow-stopping position and a flow-causing position whereby, when the recipient inhales, said second diaphragm member is in the flow-causing position thereby causing the second gas to flow from said control chamber region, through said venting chamber region and into the ambient air environment which, in turn, causes said first diaphragm member to be in the flow-supplying position thereby delivering the first gas from the first source of pressurized first gas to the recipient and, when the recipient exhales, said second diaphragm member is in the flow-stopping position thereby preventing the second gas to flow from said control chamber region, through said venting chamber region and into the ambient air environment which, in turn, causes said first diaphragm member to be in the flow-blocking position thereby preventing delivery of the first gas to the recipient;

(c) a supply orifice element having a supply orifice formed therethrough, said supply orifice element disposed between said first source of the first gas and said supply chamber region of said supply valve, said supply orifice providing fluid communication between said first source of pressurized first gas and said supply chamber region of said supply valve; and

(d) a bolus chamber structure defining a bolus chamber therein and disposed between and in fluid communication with supply orifice element and said supply chamber region of said supply valve.

12. A pneumatically-operated gas demand apparatus coupled in interruptible fluid communication between a recipient and a first source of a pressurized first gas and adapted for controlling delivery of the first gas to the recipient as the recipient inhales and exhales, comprising:

(a) a supply valve including a supply valve housing defining a first interior chamber formed therein and a flexible first diaphragm member disposed within said first interior chamber and connected to said supply valve housing in a manner to divide said first interior chamber into a supply chamber region and a control chamber region, said supply chamber region being in interruptible fluid communication with and between the first source of the first gas and the recipient, said control chamber region being in continuous fluid communication with a second source of a pressurized second gas, said first diaphragm member operative to hermetically seal said supply chamber region and said control chamber region from one another and to move between a flow-blocking position and a flow-supplying position;

(b) a sensing valve including a sensing valve housing defining a second interior chamber formed therein and a flexible second diaphragm member disposed within said second interior chamber and connected to said sensing valve housing in a manner to divide said second interior chamber into a venting chamber region and a sensing chamber region, said venting chamber region being in interruptible fluid communication with and between said control chamber region of said first interior chamber of said supply valve and an ambient air environment, said sensing chamber region being in continuous fluid communication with the recipient, said second diaphragm member operative to hermetically seal said venting chamber region and said sensing chamber region from one another and responsive when the recipient inhales and exhales to move between a flow-stopping position and a flow-causing position whereby, when the recipient inhales, said second diaphragm member is in the flow-causing position thereby causing the second gas to flow from said control chamber region, through said venting chamber region and into the ambient air environment which, in turn, causes said first diaphragm member to be in the flow-supplying position thereby delivering the first gas from the first source of pressurized first gas to the recipient and, when the recipient exhales, said second diaphragm member is in the flow-stopping position thereby preventing the second gas to flow from said control chamber region, through said venting chamber region and into the ambient air environment which, in turn, causes said first diaphragm, member to be in the flow-blocking position thereby preventing delivery of the first gas to the recipient;

(c) a regulator mechanism disposed between and in interruptible fluid communication with the source of pressurized oxygen and said supply chamber region of said supply valve; and

(d) a bolus chamber structure defining a bolus chamber therein and disposed between and in fluid communication with said regulator mechanism and said supply chamber region of said supply valve.

13. A pneumatically-operated gas demand apparatus according to claim 12 including a supply orifice element having a supply orifice formed therethrough, said supply orifice element disposed between said regulator mechanism and said bolus chamber, said supply orifice providing fluid communication between said regulator mechanism and said bolus chamber.