US 2004/0000617 A1 · Temperature compensating inflation device

Abstract

A dual stage hybrid inflation device includes a pressure switch that prevents the second stage pyrotechnic gas generator from being initiated when the additional heat and gas would overpressurize the first stage pressure vessel. As the pressurized gas stored in the first stage pressure vessel escapes the first stage pressure vessel, the pressure in the first stage pressure vessel drops. If the pressure in the first stage pressure vessel drops below the threshold pressure of the pressure switch, the pressure switch closes allowing the voltage signal to reach the pyrotechnic gas generator thereby initiating the second stage gas source. In an alternative embodiment, the pressure transducer is replaced by a pressure transducer or a temperature transducer and timing circuit. By delaying the initiation of the second stage gas source until after the pressure in the first stage pressure vessel has dropped below the threshold level, the appropriate augmentation of the compressed first stage gas can be realized without the necessity of designing the first stage pressure vessel to withstand initiation of the pyrotechnic gas generator under maximum inflation pressure conditions.

Claims43

Dependent claims

Apparatus for inflating an inflatable device comprising:

a first stage gas source comprising;
a first stage pressure vessel having a gas exit opening,
a pressurized cold gas stored within said first stage pressure vessel, and
a remotely actuated valve, in fluid communication with said gas exit opening and responsive to an external signal for opening to provide a gas flow path between said first stage pressure vessel and said inflatable device;
a second stage gas source having a gas output directed into said first stage pressure vessel;
an initiator for initiating said second stage gas source, a sensor having an output signal indicative of one of the physical properties of the pressurized cold gas consisting of temperature and pressure;
and
a electronic circuit having an input for receiving a signal from said sensor and an output for initiating said second stage gas source, said electronic circuit operating to delay initiation of said second stage gas source for a period of time after said remotely actuated valve opens, the length of said period of time being determined based upon said output signal from said sensor.

5 more elements

Apparatus for inflating an inflatable device comprising:

a first stage gas source comprising;
a first stage pressure vessel having a gas exit opening,
a pressurized cold gas stored within said first stage pressure vessel, and
a remotely actuated valve, in fluid communication with said gas exit opening and responsive to an external signal for opening to provide a gas flow path between said first stage pressure vessel and said inflatable device;
a second stage gas source comprising;
a second stage pressure vessel having a gas exit aperture in fluid communication with said first stage pressure vessel;
a frangible seal disposed in said gas exit aperture, said frangible seal operable to open said gas exit aperture to permit gas to flow through said gas exit aperture when pressure in said second stage pressure vessel exceeds a predetermined level;
a compressed gas stored within said second stage pressure vessel;
and
a pyrotechnic material contained within said second stage pressure vessel,
an initiator for initiating said second stage gas source,
a sensor having an output signal indicative of one of the physical properties of the pressurized cold gas consisting of temperature and pressure;
and
a electronic circuit having an input for receiving a signal from said sensor and an output for initiating said second stage gas source, said electronic circuit operating to delay initiation of said second stage gas source for a period of time after said remotely actuated valve opens, the length of said period of time being determined based upon said output signal from said sensor.

11 more elements

Apparatus for inflating an inflatable device comprising:

a first stage gas source comprising;
a first stage pressure vessel having a gas exit opening,
a pressurized cold gas stored within said first stage pressure vessel,
a remotely actuated valve, in fluid communication with said gas exit opening and responsive to an external signal for opening to provide a gas flow path between said first stage pressure vessel and said inflatable device;
and
an aspirator disposed between said remotely actuated valve and said inflatable device,
a second stage gas source comprising a pyrotechnic material having a gas output directed into said first stage pressure vessel;
an initiator for initiating said second stage gas source,
a sensor for measuring the pressure of the pressurized cold gas;
and
a electronic circuit having an input for receiving a signal from said sensor and an output for initiating said second stage gas source, said electronic circuit operating to delay initiation of said second stage gas source until after said remotely actuated valve has opened and the pressure of said pressurized cold gas drops below a predetermined level.

8 more elements

A method for inflating an inflatable device comprising:

storing a first stage gas in a first stage pressure vessel;
sensing one of the physical properties of said first stage gas consisting of temperature and pressure with a transducer and providing an output signal indicative said of one of the physical properties of said first stage gas;
opening a remotely operated valve in response to an external signal to release said first stage gas through said valve into said inflatable device;
and
thereafter initiating a second stage gas source having a gas output directed into said first stage pressure vessel, said initiating of said second stage gas source occurring after a delay period, the length of said delay period being determined by said output signal indicative of said one of the physical properties of said first stage gas,
whereby said second stage gas source augments said first stage gas flowing through said valve into said inflatable device.

3 more elements

Apparatus for inflating an inflatable device comprising:

means for storing a first stage gas in a first stage pressure vessel;
means for sensing one of the physical properties of said first stage gas consisting of temperature and pressure with a transducer and providing an output signal indicative said of one of the physical properties of said first stage gas;
means for opening a remotely operated valve in response to an external signal to release said first stage gas through said valve into said inflatable device;
and
means for initiating a second stage gas source having a gas output directed into said first stage pressure vessel, said initiating of said second stage gas source occurring after a delay period, the length of said delay period being determined by said output signal indicative of said one of the physical properties of said first stage gas.

2 more elements

Dependencies are inferred from the claim text.

Temperature compensating inflation device

Life of this patent

Temperature compensating inflation device

Life of this patent

Abstract

Claims43