Pressure gas operated pump

Abstract

A pressure gas operated pump, comprises, a housing which has two spaced apart double pump chambers, with diaphragms stretched across each pump chamber so as to define a driving fluid chamber and a pump fluid chamber and a rigid coupling interconnects the diaphragms. There are valve inlet and outlet passages connected into the respective pump fluid chambers for handling the pump fluid during the movement of the diaphragm. A control valve is mounted in a control valve chamber, and it is connected to the fixed coupling by means of a bar spring which has its center portion fulcrummed on a contact with the wall of a bore through a transverse thin member of the housing. The driving gas is directed onto the valve chamber and it flows through the center of the valve member and, depending upon the position of the valve, which is regulated by the diaphragm, it will flow into respective ones of the two driving fluid chambers. The valve is held in an end position in which it is connected to supply pumping fluid to one chamber and to discharge fluid from the other chamber by biasing detent means. The biasing detent means are set with a biasing force which is produced on ball locks which engage into recesses of the valve member with a force which is less than the movement force of the bar spring of the coupling member and the friction overcome by the movement of the piston valve, so that it may be moved rapidly into its other end position during switching.