Abstract: 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 pres

Abstract: A diaphragm or non-return valve is disposed in a supporting wall and includes a diaphragm plug and a valve seat having a passage opening surrounded by a continuous surface for sealing adhesion contact of a sealing lip of the diaphragm plug. The diaphragm plug is made as one piece and is of the same elastic, flexible material as the supporting wall, from which the diaphragm plug is separated along its perimetric edge by slots having a predetermined length. The diaphragm plug and the supporting wall are connected by at least two material bridges provided on opposite sides of the perimetric edge of the diaphragm plug, and the valve seat is configured as a shaped plate locked to the supporting wall in a position coincident with the diaphragm plug by a tightening ring, the valve seat and the tightening ring being engaged by elements passing through at least part of the slots.

Abstract: 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.

Abstract: An underwater mask includes a frame, a transparent part, a seal part mounted on the frame, and a snorkel. The seal part has a partition wall forming an upper and a lower chamber, the lower chamber receiving nose and mouth of the user. The two chambers communicate through a passage in the partition wall and a one-way valve so that air can pass only from the upper chamber to the lower chamber. The snorkel has first and second channels through which the upper and respectively lower chamber communicate with the outside. A connection end between snorkel and mask is fastened at an opening of the seal part to put the first channel of the snorkel in communication with the upper chamber of the mask, and further has a side inlet for a corresponding exhaust tube that puts the lower chamber in communication with the second channel of the snorkel.

Abstract: 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.

Abstract: An underwater mask includes a frame, a transparent part, a seal part mounted on the frame, and a snorkel. The seal part has a partition wall forming an upper and a lower chamber, the lower chamber receiving nose and mouth of the user. The two chambers communicate through a passage in the partition wall and a one-way valve so that air can pass only from the upper chamber to the lower chamber. The snorkel has first and second channels through which the upper and respectively lower chamber communicate with the outside. A connection end between snorkel and mask is fastened at an opening of the seal part to put the first channel of the snorkel in communication with the upper chamber of the mask, and further has a side inlet for a corresponding exhaust tube that puts the lower chamber in communication with the second channel of the snorkel.

Abstract: Diaphragm valve or non-return valve in combination with a supporting wall (3) for said diaphragm valve, which supporting wall is made of flexible and elastically deformable material such as rubber, silicone, or the like, and wherein said valve comprises: a diaphragm plug (130) of elastic, flexible material; a valve seat (50) with at least one passage opening surrounded by a continuous surface closed on itself, for sealing adhesion contact of at least one corresponding sealing lip of the diaphragm plug.