AIR-OPERATED PUMP Russian patent published in 1995 - IPC

FIELD: pump engineering. SUBSTANCE: driving cylinder is mounted inside a housing. The housing has inlet and outlet openings for compressed and exhaust gases. The cylinder is provided with two axially alined pistons of different diameters. The pistons is mounted to define small and large piston chambers and inter-piston chamber. A plunger coupled with the pistons is received in the piston cylinder. The pusher is mounted in both pistons. One of gates of the pusher is received in the large piston chamber and the other one in the small piston chamber. The discharging passage is made in the large piston. The inlet opening is made in the wall of the small piston chamber and the outlet opening is made in the wall of the inter-piston chamber. EFFECT: enhanced efficiency. 1 cl