F
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F04
POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
F04C
ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
F04C18/00
Rotary-piston pumps specially adapted for elastic fluids