Pilot regulator

In a breathing apparatus for supplying fluid under pressure to a user on demand and at ambient pressure, the breathing apparatus including a casing having an inlet for fluid under pressure, and an outlet for a user:

• a pilot valve and main valve assembly within said casing and connected to the inlet comprising a control chamber within said assembly, a main diaphragm valve subassembly segregating said control chamber from the breathing apparatus inlet, a pilot valve subassembly located within said control chamber at an end thereof opposite said diaphragm valve and means communicating fluid from said inlet to said control chamber whereby, in response to user demand, said pilot valve is opened to reduce pressure within said control chamber to open said main diaphragm valve and, upon termination of user demand, said pilot valve closes, pressure in said control chamber equalizes with inlet pressure through said fluid communicating means and said main diaphragm valve closes in response to control chamber pressure and by virtue of its own elastic memory, said pilot valve subassembly further including a movable chamber housing said pilot valve therewithin and being slidable axially within said control chamber through said opposite end thereof, said control chamber further comprising sealing means between said control chamber opposite end and said movable chamber of said pilot valve subassembly, and spring means urging said pilot valve subassembly chamber into engagement with said sealing means, said spring means being of a predetermined load whereupon in the event of a predetermined overpressure condition existing within said control chamber, said pilot valve subassembly chamber will move away from said sealing means to bleed overpressure fluid into said casing.

A breathing apparatus for supplying fluid under pressure to a user on demand and at ambient pressure comprising:

• a casing;
• an inlet passage in said casing for receiving fluid under pressure;
• an outlet passage in said casing for supplying fluid to a user on demand;
• a valve body within said casing and communicated with said inlet passage;
• means defining a control chamber within said valve body;
• an elastomer diaphragm valve at one end of said control chamber segregating said inlet passage from said control chamber;
• a pilot valve assembly mounted within said control chamber at an end generally opposite said one end having an inlet communicating with said control chamber and an outlet communicating with said outlet passage;
• a diaphragm in said casing responsive to user demand;
• means interconnecting said casing diaphragm and pilot valve assembly whereby upon user demand sensed by said casing diaphragm said pilot valve is opened;
• means communicating fluid from said inlet passage to said control chamber;
• and means defining a valve seat for said diaphragm valve within said control chamber and communicated with said casing and thus said outlet passage whereby, in response to user demand, said pilot valve is opened to reduce pressure within said control chamber thereby causing said diaphragm valve to open and both, said pilot valve and said diaphragm valve supply fluid to the user and, at the termination of user demand, said pilot valve closes, pressure in said control chamber equalizes with source pressure through said fluid communicating means and said diaphragm valve closes in response to said control chamber pressure and by virtue of its own elastic memory, said casing further comprising a baffle dividing said casing into two sections, one containing said valve body and the other having said casing diaphragm located therein, both of said sections being in communication with said outlet passage, said baffle being positioned to deflect substantial fluid flow from both said diaphragm valve and said pilot valve to said outlet passage rather than to said second section.