CPC Subgroup
F04B 19/022 Full Title
Machines or pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B1/00 - F04B17/00 > having movable cylinders
F04B 19/022 Machines or pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B1/00 - F04B17/00 > having movable cylinders