Flexible seismic gas exploder

Claim 1

A seismic gas exploder for abruptly releasing high-pressure gases into a liquid medium surrounding said exploder, said exploder comprising; a housing defining a combustion chamber and a secondary chamber, said housing being rigid to prevent the transmission of mechanical energy into said liquid medium; a gas supply system for periodically supplying to said combustion chamber a charge of a combustible gas mixture under pressure, said supply system including ignition means for detonating said mixture in said combustion chamber, a movable piston sealing off said combustion chamber from said secondary chamber and from said liquid medium when said piston is in its stable biased position, thereby allowing said gas mixture to become confined under pressure within said combustion chamber; a gas discharge path through said housing for establishing fluid communication between the volume of said combustion chamber and said liquid medium; said combustible gas mixture upon becoming ignited moving said piston away from said stable biased position to an unstable biased position thereby expanding the volume of said combustion chamber and reducing the volume of said secondary chamber, the substantially instantaneous removal of said piston from its stable position allows the abrupt application of a highpressure gas wave through said path into said liquid medium, thereby generating a powerful acoustic pulse in said liquid medium; and bias means in said secondary chamber to: 1. maintain said piston in its stable position, 2. cushion the impact of said piston on said housing, and 3. urge said piston from its unstable position to its stable position following the release of said high-pressure gas wave into said liquid medium by said combustion chamber.