Patent GB-580161-A (GB)
Title: Machine having free pistons and cylinders without mechanical connecting-rod-crank couplings
IPC: F02B71/00
Filed: 1940-03-01
Abstract: 580,161. Free-piston compressors. MERCIER, E. March 1, 1940, No. 3894. [Classes 8 (i) and 102 (i)] [Also in Group XXVII] A free-piston motor compressor or compressed gas generator comprises a pair of motor cylinders 7 and a double-acting aircompressing cylinder 4 or two single-acting cylinders, the movable elements being combined into two oppositely moving systems synchronized by balance levers 22, the motor pistons 2, 5, compressor piston 1 and heads of the motor and compressor cylinder(s) all being movable. The length of. the arms of the levers 22 are inversely proportional to the connected masses, one of which may include the inner motor pistons 2 and compressor piston 1 and the other may include the outer motor pistons 5 and compressor cylinder 4; the masses may be equal. Air is drawn in through valves in the ends of cylinder 4 and expelled through valves in. piston 1 to the interior of the piston and the hollow rod 3 connecting it with pistons 2 and so into intermediate receivers 8. The motor cylinders are fed from the receivers through ports 28, and exhaust through ports 29; alternatively, the inlet ports may be at mid-length, and exhaust ports at each end, the inlet ports being closed by a ring actuated by the lever shaft and protected by baffles in the ports against radiation. The fuel pump, Fig. 11, is operated by an arm on the shaft 6 of lever 22, and its operation is adjusted by. a rotatable sleeve 41 with helical slots 45, 46 co-operating with longitudinal grooves 43, 44 in the pump body, the fuel being delivered through groove 43 and valve 48 to the injection valves until the piston has passed the intersection of grooves 43, 45 after which the fuel is returned through pipe 53 to the upper side of the piston. On the upward stroke fuel passes back through valve 52 until the piston passes the intersection of grooves 44, 46 after which it is forced through valve 50 to the injection valves for advanced injection and ignition. The shaft 6 also carries three cams one of which operates during excessive strokes to supply oil by a first piston to a second piston actuating the sleeve 41 to reduce the injection of fuel, the first piston being returned by a spring to reverse the oil flow and bring the sleeve back to normal position between two cam actions. The other cams control rings controlling communication of the receivers 8 with exhaust, in the modified apparatus above mentioned. A manual control acts on the slide valve of a servomotor to control the movement of the rings, adjustment of the cams, and movement of rings controlling relief ports in the compressor wall. Spring- pressed closures in the compressor 'end walls opposite the piston valves close these valves to exhaust to cushion the piston against impact; a safety-valve may be provided in the end plate. In another form, the outer motor pistons are connected to the compressor piston by tierods passing through the chambers 8; the compressor cylinder is united with the inner motor pistons through the hollow rod 3 and its ends contain both the inlet and exhaust valves. In a further form, the outer pistons of Fig. 1 are replaced by ordinary cylinder heads connected. with the compressor cylinder.