In an example, a cover device for a regulator, which has a purge button and a mouthpiece connected to the regulator, includes a body which has: a mouthpiece housing to receive the mouthpiece through an access opening which presents a friction fit to squeeze the mouthpiece passing therethrough in a squeezed state to enter and exit a hollow interior of the mouthpiece housing, the hollow interior configured to store the mouthpiece in a relaxed state; a regulator support connected to the mouthpiece housing to support a bottom surface of the regulator when the mouthpiece is inserted into the hollow interior of the mouthpiece housing; and a button cover connected to the mouthpiece housing to cover the purge button on a top surface of the regulator when the mouthpiece is inserted into the hollow interior of the mouthpiece housing, while exposing a portion of the top surface of the regulator surrounding the purge button.

A pressure-reducing system for a breathing apparatus comprising: i) a supply conduit (2) for supplying a pressurised breathable gas; ii) a suction mouthpiece (3) for a user to breathe in the breathable gas; iii) a valve (4) operatively interposed between the supply conduit (2) and the suction mouthpiece (3), the valve (4) in turn comprising: -an inlet (41) for the breathable gas coming from the supply conduit (2); -an outlet (42) for the breathable gas directed to the suction mouthpiece; -a shutter (43) that is movable between a first and a second position in which it respectively permits or prevents the passage of the breathable gas from the inlet (41) to the outlet (42); -a pressure balancing chamber (44), said shutter (43) being interposed between the inlet (41) of the valve (4) and the balancing chamber (44); the shutter (43) defining a conduit (430) that places the inlet (41) of the valve (4) and the pressure balancing chamber (44) in fluid communication; iv) a movement system (5) for moving the pressure balancing chamber (44) towards the inlet (41) for the breathable gas to push the shutter (43) from the first position to the second position.

Methods and systems to provide breathing air to underwater divers in response to the divers' respiration at pressures less than 25 psi above atmospheric pressure during inspiration while delivering no or minimal air during exhalation, by controlling the actions of a pump during the time course of breathing. Methods and systems that sense a diver's need for breathing air, determine inhalation demand or exhalation state, and control the operation of a pump which delivers breathing gas to the diver via a tube. An integrated system for the same which incorporates at least an energy source (26), pump (28), air tube (30), breathing aperture (10), sensor (20), and logic processor (24) is disclosed.

A pressure regulator assembly for an SCBA includes a valve assembly having a piston, a cylinder for receiving the piston, a sealing member for engagement by the piston, a conduit extending through the piston and facilitating fluid communication between an inlet chamber and a cavity of the cylinder, and a driving assembly for facilitating the engagement and disengagement of the piston responsive to a change of pressure in the outlet chamber. A bypass assembly for an SCBA is also disclosed.

A cover device for a regulator, which has a purge button and a mouthpiece connected to the regulator, includes a body having a mouthpiece housing to receive the mouthpiece through an access opening which presents a friction fit to squeeze the mouthpiece passing therethrough in a squeezed state to enter and exit a hollow interior of the mouthpiece housing. The hollow interior is configured to store the mouthpiece in a relaxed state. A button cover is connected to the mouthpiece housing to cover the purge button on a top surface of the regulator when the mouthpiece is inserted into the hollow interior of the mouthpiece housing. The button cover is narrower in width than the mouthpiece housing.

A pressure regulator assembly for an SCBA includes a valve assembly having a piston, a cylinder for receiving the piston, a sealing member for engagement by the piston, a conduit extending through the piston and facilitating fluid communication between an inlet chamber and a cavity of the cylinder, and a driving assembly for facilitating the engagement and disengagement of the piston responsive to a change of pressure in the outlet chamber. A bypass assembly for an SCBA is also disclosed.

A second pressure-reducing stage for underwater use includes a supply duct of a breathable gas, in which a valve of a pressure reducing device to reduce the pressure of the breathable gas is provided, the valve being interposed between an inlet of the supply duct and a suction/exhalation mouth to suction/exhale the breathable gas; a casing containing a pressure-sensitive device to control the opening/closing of the valve, the supply duct and the suction/exhalation mouth leading into the casing; and a bypass duct for supplying at least part of the flow of the breathable gas from the supply duct, downstream of the valve, directly into the suction/exhalation mouth, the by-pass duct joining the suction/exhalation mouth through an opening having an axis oriented in a direction which converges towards the axis of the suction/exhalation mouth.

A regulating membrane for a second stage regulator of two-stage underwater breathing apparatuses includes a continuous flexible side wall, tapered from the peripheral edge towards the top, that has a rigid plate disposed in central position and coaxial to the flexible sidewall, the flexible side wall being provided with at least one continuous or discontinuous lateral reinforcing element, possibly protruding outwardly and/or inwardly from the regulating membrane, to support and guide the collapsing movements of the plate with respect to the regulating membrane.

A system for controlling the exhalation pressure of a diver for diving equipment with a ventilation circuit, includes a unidirectional valve acting on an exhalation outlet of the ventilation circuit, and a brake configured to exert an adjustable constraint on the unidirectional valve in order to control the pressure of the gas from the exhalation outlet so as to generate a positive exhalation pressure in the ventilation circuit of the equipment and thus prevent or treat immersion pulmonary edemas.

A pressure reducing system for a breathing apparatus may include a conduit and a mouthpiece. The system may also include a valve poppet operatively interposed between the conduit and the mouthpiece, the valve poppet being movable between a closed position and an open position. The conduit may include an abutment against which the valve poppet abuts in the closed position and from which the valve poppet is distanced in the open position, and the abutment may define an annular interface which in the closed position is in contact with the valve poppet. The system may also include a balancing chamber that defines a pressure balancing zone. The valve poppet may define a passage that places the conduit and the pressure balancing chamber in fluid communication and a section of said passage, in the open positions extends in the supply conduit beyond said annular interface.