GB269572A - Improvements in damper regulators for steam boiler furnaces - Google Patents

Abstract

269,572. Backlund, I. A. April 13, 1926, [Convention date]. Draught, regulating.-In a damper regulator operated by boiler pressure through servo-motor mechanism, an intermediate servo-motor 25, 24 is inserted between the boiler-pressure actuated valve 36 and the damper piston 7 and the resetting means for the pilot valve 36 comprises a weight 55 controlled by the pressure fluid supplied to the damper piston 7. In the apparatus illustrated, the diaphragm 51 exposed to boiler pressure is connected to a weighted lever 45 carrying the pilot valve 36 which controls the connection of pressure (from supply 20) and exhaust (to outlet 22) with pipe 40 opening beneath the piston 25 operating the second valve 14, which in turn controls connections of pressure and exhaust to the main piston 7 and also to a piston 57 connected by cable with the resetting weight 55. The weight 55 when lowered by the raising of the piston 57 rests on the lever 45 and by adjustment of its amount the limits within which the boiler pressure is maintained are determined. The pistons 7, 25 and 57 are loaded by weights secured to frames attached to the piston rods. In a modification, the valve 14 and piston 25 are combined in a single cylinder.