Abstract: A demand regulator for use in underwater breathing apparatus employs a vane member dividing the mouthpiece tube into two adjacent air passageways. An interior end of the vane is configured as an air deflector for conducting pressurized air out of the mouthpiece tube substantially through only one of the passageways. The opposite end of the vane is provided with an inclined tab for applying back pressure to the air exiting from the mouthpiece tube, whereby the venturi action of the exiting pressurized air, and consequent free flow tendency of the regulator, are controlled.

Abstract: A demand regulator for use in underwater breathing employs a longitudinally movable tubular valve member having a transversely opening outlet orifice which is moved relative to the breathing port of the regulator as the valve member is moved axially between the fully opened and fully closed positions.

Abstract: The venturi action in a demand regulator is controlled by moving a baffle across an air inlet into the regulator chamber as the inlet valve is opened.

Abstract: A demand regulator for use in underwater breathing employs a deflector carried by a valve operating lever for movement between the air outlet in the breathing chamber and the mouthpiece tube to reduce the portion of air supplied directly to the mouthpiece as the air flow is increased.

Abstract: A demand regulator for use in underwater breathing employs a deflector carried by a valve operating lever for movement between the air outlet in the breathing chamber and the mouthpiece tube to reduce the portion of air supplied directly to the mouthpiece as the air flow is increased.

Abstract: A diver's buoyancy compensator employs a constant volume chamber which is controllably pressurized with air from the diver's SCUBA tank, and water is admitted to or emitted from the tank by one or the other of two manually operated valves.

Abstract: An inflatable buoyancy vest employs an open weave elastic gusset between the front and rear panels of the vest to hold the vest in a compact condition when the vest is deflated.

Abstract: A filter formed of minute fibers of borosilicate glass is mounted to the inlet-outlet valve of a rechargeable pressure vessel to remove entrained particles from fluid entering and exiting the vessel.

Abstract: The inhalation tube of a pressure regulator is divided by means of a baffle curved at its inner end adjacent the side wall of the chamber so that when the regulator is in the water with the mouthpiece open, water is channeled into the regulator chamber through the inhalation tube along one side of the baffle and air flows out through the tube along the other side of the baffle.