Variable dome valves and combustors provided with said valves

Claim 1

A variable dome valve, adapted to be mounted on the upstream dome end of a flame tube in a combustor for controlling flow of a stream of combustion air into said flame tube, said valve comprising: a fixed generally cylindrical inner member, closed at one end to the flow of said combustion air and open to the flow of said combustion air at the other end; a plurality of openings provided at spaced apart locations around and extending through the cylindrical wall of said inner member adjacent said closed end thereof; a mounting flange secured to and around said inner member adjacent said open end thereof for mounting said valve on a said flame tube; an adjustable throttle ring rotatably mounted on and around said cylindrical inner member; a plurality of openings provided around and extending through said throttle ring, said openings being of a size, a shape, a number, and located at spaced apart locations, corresponding to said openings in said inner member, and means for rotating said throttle ring around said inner cylindrical member so as to bring said openings in said throttle ring into and out of register with said openings in said inner member and vary the effective combined open area of said openings and thereby control the flow of said stream of combustion air into said flame tube, wherein: a groove is provided in said mounting flange adjacent and around the base of said cylindrical inner member; said throttle ring seats in and rotates in said groove; a pair of spaced apart stop pins extend perpendicularly from said flange and adjacent the outer wall surface of said cylindrical inner member; and said means for rotating said throttle ring comprises an actuator pin extending radially from the outer wall surface thereof at a location between said stop pins.