Control means for regulating the capacity of reciprocating compressors

932,277. Compressor unloading means. WORTHINGTON CORPORATION. March 15, 1962, No. 10044/62. Class 8(1). A compressor inlet valve (not shown) is held in its unloaded position by pins 12, Fig. 1, carried by a piston 13 within a chamber 9 which when subjected to oil pressure through a pipe 7 allows the valve to assume its nominal working position, the oil supply being controlled by a device 2 comprising a casing 20, Fig. 2, within the crankcase 5 in which is disposed a piston 24 which when moved inwardly against a spring 27 by the pressure of oil admitted from the crankcase through a pipe 6 to an annular chamber 21 surrounding the piston and through a bore 32 in the piston head to a chamber 38 formed within a nozzle 34 having an outlet 33 controlled by an adjustable plug 50 allows pressure oil to gain access to the pipe 7 until such time that the end of outlet 33 is uncovered by plug 50 which is carried by a lever 51 pivoted to a casing bracket 53 and connected by a rod 73 to a bellows 70 disposed within a chamber 71 connected by a pipe 72 to the compressor inlet manifold.