Process and device for improving working of liquid pumps

Claim 1

A pumping system for a spring assisted diaphragm pump having a pump housing, a diaphragm dividing the housing into a pumping chamber having means for pump discharge and for pump intake, and a pump actuating chamber having an opening substantially concentric with the diaphragm, said actuating chamber adapted to receive a fluid pressure medium acting upon one side of the diaphragm to produce the pumping stroke and means for predetermining the distance of the pumping stroke comprising, (a) an actuating rod extending from said diaphragm through said pump actuating chamber opening in said pump housing with a major portion of the length of said rod outwardly exposed of the pump housing, (b) said pump actuating chamber adapted to be filled by liquid at the other side of said diaphragm with said actuating rod displaceable between a first extreme position in a first direction within said pump housing when said actuating chamber is filled with said liquid and to a second extreme position in an opposite direction when said actuating chamber is emptied of said liquid, (c) a casing surrounding the exposed length of the rod connected to said pump housing with an upper end portion of said actuating rod extending through the upper end of said casing, (d) stroke detecting means located at said exposed portion of said actuating rod including sensing means comprising a bottom sensor for detecting said first extreme position of said actuating rod and a top sensor for detecting the other extreme position of said actuating rod, (e) actuating means interconnected with said sensing means for receiving a signal for said sensing means controlling movement of said actuating rod and interconnected pump diaphragm, and (f) a timer connected to the sensing means adapted to set a predetermined cycle time for authorizing operation of said actuating means for the emptying and filling said pump actuating chamber, (g) said actuating means comprising an electromagnetic device operable to open and close a valve member to a source of compressed air to said pump actuating chamber.