DEMAND, SOLID-PROPELLANT GAS GENERATOR

• US 3,701,256 A
• Filed: 09/13/1971
• Issued: 10/31/1972
• Est. Priority Date: 09/13/1971
• Status: Expired due to Term

• Current Assignee: Albert Ray Osburn, Joseph E. Pelham
• Original Assignee: Albert Ray Osburn, Joseph E. Pelham
• Inventors: Pelham, Joseph E., Osburn, Albert Ray
• Primary Examiner(s): Hart, Douglas
• Assistant Examiner(s): Garrett, Robert E.
• Application Number:
  US05/179,687
• Time in Patent Office: 414 Days
• Field of Search: 60/234,39.47,254,256,250,253,39.09 102/34.5,49.7,49.8
• US Class Current: 60/39.47
• CPC Class Codes: F02K 9/94 Re-ignitable or restartable rocket- engine plants; Intermittently operated rocket-engine plants

Abstract

An orificed pressure vessel has a combustion chamber adjacent the orifice and a propellant charge in the remainder thereof comprising wafer segments of propellant separated from each other by combustion barriers; an electric igniter adjacent each propellant wafer has a thermally operated, normally open switch, so that the circuit is closed for each igniter as the adjacent wafer is burned; a pressure transducer in communication with the combustion chamber operates a master switch connected in series with the igniters and an electrical energy source to close the entire circuit or open it in response to a predetermined maximum and minimum chamber pressure; and valve means on the orifice permits withdrawal of gases from the combustion chamber for use as desired. Optional equipment includes a pressure relief valve in the combustion chamber and a capacitor connected in parallel between the energy source and the igniters.

Claims

1. A gas generator comprising:

an orificed pressure vessel having a combustion chamber adjacent the orifice;

a solid propellant charge in the pressure vessel comprising wafer segments of propellant and combustion barriers separating and sealing the wafer segments from one another;

an electrically operated igniter adjacent each wafer segment of propellant;

an electrical energy source connected to the igniters in a circuit;

switch means connected in the circuit for selectively firing the igniters in series;

a pressure transducer in communication with the combustion chamber for monitoring the pressure thereof and operatively connected to the switch means, for interrupting and restarting combustion of the propellant in response to pressure changes within the combustion chamber; and

valve means on the orifice, whereby gas from the combustion chamber may be withdrawn for use as desired.

2. The gas generator of claim 1 further including a pressure regulator in tandem with the valve means, for metering gases therethrough at a desired pressure.

3. The gas generator of claim 1 further including a pressure relief valve in the pressure vessel wall, whereby escape of excess gas may be permitted when the pressure in the combustion chamber is higher than a predetermined maximum.

4. The gas generator of claim 1, further including a capacitor connected in parallel between the igniters and the energy source to insure an electrical pulse of sufficient strength to fire each electric squib without failure.

5. A gas generator comprising:

a cylindrical pressure vessel having domed ends, with an orifice in one end and a combustion chamber adjacent the orifice;

a propellant charge filling the vessel except for the combustion chamber, comprising wafer segments of propellant and combustion barriers sealing off the wafer segments from one another, the combustion barriers being made of noncombustible elastOmeric material;

a film of pyrotechnic material on the combustion chamber side of each propellant wafer;

an electric squib in contact with each pyrotechnic film;

a thermally operated, normally open, electric switch connected to each electric squib, these switches being connected together in parallel so that combustion of each wafer segment of the series will automatically close the circuit for the adjacent propellant wafer;

a master switch connected in series with the squibs and their switches;

an electrical energy source connected in series with the master switch and the squibs;

a capacitor connected in parallel between the energy source and the squibs;

a pressure transducer mounted in the wall of the pressure vessel in communication with the combustion chamber thereof and operatively connected to the master switch to open the circuit when the pressure in the combustion chamber reaches a predetermined maximum and to close it when that pressure reaches a predetermined minimum, whereby combustion of the propellant charge may be interrupted and restarted;

a pressure relief valve in the wall of the combustion chamber to permit escape of excess gas when the pressure therein reaches a predetermined maximum; and

valve means on the orifice of the pressure vessel to permit metering of gases therefrom.