F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
F01L25/00—Drive, or adjustment during the operation, or distribution or expansion valves by non-mechanical means
F01L25/02—Drive, or adjustment during the operation, or distribution or expansion valves by non-mechanical means by fluid means
F01L25/04—Drive, or adjustment during the operation, or distribution or expansion valves by non-mechanical means by fluid means by working-fluid of machine or engine, e.g. free-piston machine
F01L25/06—Arrangements with main and auxiliary valves, at least one of them being fluid-driven