GB788618A - Improvements in and relating to free-piston engine compressors and method of and apparatus for regulating the same - Google Patents

Abstract

788,618. Free piston compressors. JUNKERS MASCHINEN-UND METALLBAU GES. July 22, 1955 [Nov. 4, 1954], No. 21301/55. Class 7(2) [Also in Group XXVIII] The supply of fuel is controlled in accordance with the rate of flow of gas through the conduit from the compressor. A pressure reduction produced in a gas carrying conduit is employed to operate a spring loaded member 'coupled to means for varying the fuel supply. As shown, Figs. 1 and 2, the reduced pressure produced in a venturi 27 acts on a piston 35 coupled to a member 38 associated with the to a member 38 associated with the plunger of the fuel pump and the fuel supply is thus controlled. During operation the delivery pressure may remain practically constant or the idling pressure may be lower than the full delivery pressure. The venturi 27 may be in front of or behind the pressure retaining valve 26. A space such as the after cooler 25 should be situated between the compressor outlet and the venturi 27. Two venturi nozzles may be used one within the, other. In another modification, the effective pressure may be bled from the venturi by means of a tube which is adjustable axially of the nozzle. There may be a series of tappings spaced from each other axially along.the venturi and a selective connection with the working chamber of the piston 35 may be provided. Figs. 7 to 9 show various modified arrangements for producing a pressure drop in the compressed air conduit. The member coupled to the fuel control is referred to as a power member and the Specification also refers to a power member (piston diaphragm, bellows or the like). Reference is made to known arrangements in which cooling fans and pumps are driven by the compressed air. The invention comprises single and multi-stage compressors.