Abstract: A positive pressure demand regulator having a housing with a connection for delivering breathing gas with an outlet connected to the housing for attachment to a mask. A diaphragm is mounted in the housing and a passage connects the outlet and the diaphragm so that the diaphragm can be in fluidically connected relationship to the outlet. A main valve interconnects the breathing gas connection to the outlet for valving breathing gas to the outlet. A cam is attached to the diaphragm for lifting the diaphragm into an inoperative mode with a detent connected to the cam operated by a cam rod engaging a cam surface to lift the detent into a position for placing the detent in displaced relationship from where the diaphragm is in an operative mode, mounted in the housing on the side of the diaphragm opposite from the outlet.

Abstract: A first and second stage breathing gas regulator having a first stage redundant piston assembly with a first piston encompassing a second piston. In the eventuality the first piston fails, the second piston provides regulated gas. A safety alarm is provided when a pre-established pressure drop occurs, signalling a decrease in breathing gas by opening to provide gas to drive an audio alarm. The second stage regulator has a balanced second stage that operates with a valve lever in operative relationship to a diaphragm. A hand wheel and cammed valve permit the bypass of breathing gas around the valve of the second stage regulator when required. The outlet of the second stage regulator is provided with a trap door cover to avoid dirt and debris being introduced to the second stage regulator when a hose is not connected thereto.

Abstract: The following specification discloses a fiberoptic pressure gauge suitable for use with a tank of compressed gas. In particular, the tank of compressed gas can be utilized by an industrial worker, a fireman, or a diver wherein breathing gas has been stored in a tank to allow for delivery thereof to a user. The pressure within the tank which is indicative of the supply of gas for delivery to a user's mask, is monitored by means of a bourdon tube type of movement that is connected to a shutter overlying a lighting source, such as a light emitting diode (LED). The lighting source is in optical relationship to a plurality of fiberoptic bundles that terminate at a distal end in a plurality of ends that are placed in calibrated relationship to a plurality of numbers indicative of the pressure within the tank.

Abstract: There is disclosed an emergency breathing apparatus that provides a sustained life support for a period of time up to about 30 minutes and that is useful for fire fighters and the like in a hostile environment. The device comprises a harness with a backpack air supply cylinder provided with a shut-off valve and pressure regulator at the cylinder. The regulator has a bypass connection for attachment of a remote pressure sensor and a valve which opens when the pressure declines to a predetermined value and applies regulated air pressure to an audible warning device such as a whistle, buzzer, bell and the like. The device employs a pilot regulator on the mask which is a very compact and simple structure with only a few moving parts, and consequently, easier to manufacture and maintain than more bulky, complicated structures of the prior art.

Abstract: There is disclosed an emergency escape breathing apparatus comprising a hood to be placed over a person's head and a pressured bottle supply of air or oxygen enriched air. The hood is formed of thin film, clear plastics having an elastic neck band to permit the hood to be pulled over the wearer's head, and yieldably seals about the wearer's neck, functioning as an exhalation valve, maintaining adequate pressure to keep the hood inflated. The device is provided with a valve on the air supply bottle which has a reseatable valve member and two stages of flow control; the first stage being pressure control, providing a variable flow area which increases with declining pressure in the air supply bottle, and the second stage being flow control having a fixed diameter orifice. The bottle contains air enriched with oxygen below any hazardous oxygen content yet sufficient to provide at least 5 minutes sustained respiration of the user.

Abstract: There is disclosed an emergency escape breathing apparatus comprising a hood to be placed over a person's head and a pressured bottle supply of air or oxygen enriched air. The hood is formed of thin film, clear plastics in a tent structure having a bottom wall formed of a thin film elastomer. The elastomer film has an aperture of sufficient diameter to permit the hood to be pulled over the wearer's head and yieldably seals about the wearer's neck, functioning as an exhalation valve, maintaining adequate pressure to keep the hood inflated. The device is provided with a valve on the air supply bottle which has a reseatable valve member and two stages of flow control; the first stage being pressure control, providing a variable flow area which increases with declining pressure in the air supply bottle, and the second stage being flow control having a fixed diameter orifice. The reseatable valve member and flow control elements are all combined in a single unitary valve structure.