GB427668A - Improvements in or relating to free-piston engine gas compressors - Google Patents

Abstract

427,668. Two-stroke-cycle directacting engines. JUNKERS, H., 21, Hauptmann Loeper Platz, Dessau, Anhalt, Germany. Feb. 8, 1934, No. 4209. Convention date, Feb. 16, 1933. [Class 7 (ii)] [See also Groups XXVIII and XXIX] In a free-piston gas compressor the charge of fuel to the internal-combustion engine is adjusted to vary the stroke and simultaneously the suction or delivery pressures or both are adjusted automatically to maintain constant the recoil energy. The internal-combustion engine cylinder 1 has an inlet port 3 and an exhaust port 4, and pistons 2 are connected to pistons 10 of the compressor cylinders 5, 6. The racks 21, 22 engage a pinion 23 and a cam 26 actuates, through a lever 27, the plunger 24 of a fuel injection pump supplying an injector 29. The output of the pump 25 is adjusted by rotating the plunger 24 through pinion 30 by a spring loaded piston 32 subjected to pressure from the pressure of the receiver 14. The ratio of delivery pressure to suction pressure above the value set out in Specification 425,708, [Group XXVIII], is termed a high pressure ratio and below that value is termed a low pressure ratio. For high pressure ratios the delivery pressure should be decreased when the stroke is decreased and for this purpose a throttle valve 9 is provided which consists of a piston 44 secured to the valve 43, wherein the compressor delivery pressure upon the annular surface 45 together with the receiver pressure upon the surface 43<1> acts in opposition to the spring 46. A fall in the receiver pressure results in a greater delivery pressure being required to overcome the spring, whilst at the same time the pump 25 is adjusted to increase the fuel supply. If the pressure ratio is low the delivery pressure should be increased when the stroke is decreased and the throttle valve 9 then consists of a double beat valve 53, 54 attached to a piston 57 loaded by a spring 59 and subjected to delivery pressure on the surface 57<1>. The spring abutment 61 is adjusted by receiver pressure through pipe 60. The valve 9 may be omitted and the same result obtained by employing positively driven adjustable valves upon the compressor. Throttle valves may be employed in the suction pipes. The Specification as open to inspection under Sect. 91 states also that the discharge from the compressor cylinder does not commence until the inlet and exhaust ports are sufficiently open to permit efficient exhausting, scavenging and charging. This subject-matter does not appear in the Specification as accepted.