PUMP Russian patent published in 1995 - IPC

FIELD: pump engineering. SUBSTANCE: cylinder 2 with cover 13 is mounted inside housing 1. Piston 4 with connecting rod 5 is received in cylinder 2 to form working 3 and control 11 chambers. The connecting rod passes through the cover. A suction valve is made up as bushing 9 which encloses piston 4. The bushing is mounted for permitting movement with respect to cylinder 2 and piston 4 and has a neck for interaction with seat 8 and free face for interaction with the face of cover 13. Cover 13 is mounted for permitting axial movement, spring-loaded with spring 14 and provided with control stop 15 for forming control space between faces of cylinder and cover from the side of chamber 11. The value of the space is adjusted by stop 15 in the range from zero to maximum value of piston 4 stroke. EFFECT: enhanced efficiency. 3 dwg