Patent ID: 6878024
Filing Date: 2005-04-12
Classification: B63B

Abstract:
1. A hydrostatic release mechanism for releasing an emergency device from a vessel, the hydrostatic release mechanism comprising: a sealed housing having an interior volume, the sealed housing having a tunnel passing therethrough, said tunnel adapted to receive a tether extending therethrough, a depth sensor mounted to the sealed housing, the depth sensor having a diaphragm covering an opening between the interior volume and a diaphragm cover extending over the diaphragm opposite the interior of the sealed housing, the diaphragm cover having one or more passages therethrough which provide liquid communication between the exterior of the depth sensor and a small cavity defined by the diaphragm and the diaphragm cover, a trigger contained within the sealed housing, the trigger having a trigger pin, a plunger and a preloaded spring which are connected to the diaphragm, the preloaded spring resiliently urging said diaphragm outwardly from the interior volume with an outward force, a firing mechanism contained within the sealed housing, the firing mechanism being actuated by movement of the plunger in response to inward movement of the diaphragm when the pressure on the diaphragm exceeds the outward force, the firing mechanism having a hammer which is driven against a pyrotechnic cartridge, the pyrotechnic cartridge being mounted at one end of a barrel, the pyrotechnic cartridge firing and emitting expanding gases which are contained within the barrel, a piston mounted at the other end of the barrel, the piston moving in response to the expanding gases, the piston having a blade mounted thereon opposite the pyrotechnic cartridge whereby the force of the expanding gases is transferred to the blade via the piston, the blade being guided to pass perpendicularly through the tunnel to thereby sever the tether.