Patent ID: 6286612
Filing Date: 2001-09-11
Classification: G01V

Abstract:
A shutoff valve for use with a marine acoustic generator airgun, which airgun has a reciprocating shuttle that serves to hold a charge of pressurized air and then release the charge of pressurized air into the surrounding water to create a pressure pulse and which utilizes a source of pressurized air transmitted through a fluid flow conduit, said shutoff comprising:a housing defining a fluid inlet, a fluid outlet and a piston slidably disposed within a chamber between a first position and a second position, where the fluid inlet is coupled to the pressurized fluid conduit, the fluid outlet is coupled to the airgun and the piston defines an upper and a lower portion;said fluid inlet disposed in fluid communication with the lower portion of said piston such that the pressurized fluid directed through said fluid inlet serves to maintain said piston in said first position, where when said piston is disposed in said first position said inlet and said outlet are disposed in fluid communication with each other so as to supply pressurized air to the airgun; andsaid housing further defining a fluid flow passage disposed in fluid communication with said chamber about the upper portion of said piston such that fluid directed through said passage serves to move said piston from said first position to said second position so as to interrupt fluid communication between said inlet and said outlet.