POSITIVE DISPLACEMENT PUMP Russian patent published in 2003 - IPC

FIELD: mechanical engineering. SUBSTANCE: invention relates to diaphragm-type positive displacement pumps designed for handling aggressive, toxic and other like liquids, namely, to pumps with tubular diaphragm deformable under action of hydraulic drive liquid and suitable for handling high viscosity, badly contaminated liquids, paints, pastes, coagulating and other liquids. Proposed pump has housing with at least one sleeve accommodating displacer with drive mechanism and one working chamber formed by inner space of tubular diaphragm hermetically fixed over end faces in housing and provided with suction and delivery valves arranged at its end faces on housing. Diaphragm is arranged in housing to form, together with sleeve and displacer, a variable-volume hydraulic drive chamber hydraulically communicating with compensating chamber through channel of hydraulic drive chamber leaks compensating make-up device, said channel opens under action of displacer moving near dead point corresponding to end of suction stroke. Tubular diaphragm is furnished with cord axially symmetrically arranged in middle part of its walls and forming elastic carcass over entire length of diaphragm, including end sections of its edge restraints in housing. Make-up device channel is made at least in form of one through hole in housing sleeve. Throttling shutoff edge of housing is located at a distance of at least 3-8% of length of displacer travel in dead point per delivery stroke from end face edge of displacer sealing the throttling shutoff edge. EFFECT: enlarged operating capabilities. 5 cl, 2 dwg