Chemical feed pump with improved valve means

Claim 1

In a chemical feed pump of the type having a diaphragm, or piston, a pumping chamber, and influent and effluent valve means connected to said chamber, each valve means including a double ball check valve in tandem, the improvement comprising: a pair of identical, separable casings, each having a cylindrical valve chamber therewithin containing one of said double ball check valves in tandem; each ball check valve including a spherical ball of predetermined outside diameter and an annular ball seat of resilient material, of predetermined durometer of about 55, said seat having a sharp edged inner peripheral rim seating said ball and having a cylindrical, central axial bore forming a valve port, the outside diameter of said ball and the inside diameter of said port being in the proportion of 0.3125 to 0.190 + OR - 0.006; a hollow cylindrical ball receiving spacer within each said valve chamber, one of said balls and ball seats being at each opposite end thereof, within said valve chamber, and each ball seat being identical and reversible within said valve chamber; each said separable casing including a main casing and a threaded end closure and each having an axial fluid passage of sufficient diameter to form oppositely disposed ball recesses permitting said influent and effluent valve means to be formed by identical structure.