Reserve switch for diving equipment

Claim 1

A valve assembly for diving equipment comprising a casing having an air inlet to which a container containing pressurized air may be attached and an air outlet, passage means in said casing between said air inlet and air outlet, reserve valve means in said passage means biased in an opening direction by pressurized air in said passage means on the downstream side thereof from said valve means, valve actuator means biasing said reserve valve means when the air pressure on the downstream side of said valve means drops to a predetermined minimum pressure, said valve actuator means including a spindle and knob mounted for axial and rotational movement relative to the axis of said spindle, first guide means for confining movement of said spindle in an axial direction and second cam and follower guide means for guiding said spindle along a combination axially and rotationally extending path, said actuator means having ranges of axial and rotational movement respectively relative to said guide means with a range of axial movement being automatic relative to said first guide means and a range of combined and rotational movement being manually controllable relative to said second guide means, said valve actuator means being transferable from said first guide means to said second guide means only at a point corresponding substantially to said minimum pressure.