Patent ID: 8469681

Claim:
A double-diaphragm pump comprising a pair of axially spaced apart pumping chambers, each chamber having a pumping diaphragm which divides each chamber into an inner and an outer compartment, the inner ends of both pumping chambers being formed by a central element, a mechanism supplying fluid to the outer compartments to cause the diaphragms to oscillate and vary the capacities of the inner compartments and each of the inner compartments having an inlet port leading to an inlet manifold in the central element and an outlet port leading to an outlet manifold in the central element, and wherein unidirectional valves are located inside of the inlet and outlet manifolds to allow fluid to be drawn into one of the compartments through the inlet port of that compartment from the inlet manifold of that compartment when the appropriate diaphragm moves outwardly and to allow the fluid to be expelled from that compartment through the outlet port of the compartment into the outlet manifold of that compartment when the diaphragm moves inwardly, and in which the unidirectional valves are accessed and fitted through the inlet and outlet ports in the inner compartments when the diaphragms are absent, and wherein the inlet and outlet manifolds within the central element extend away from their respective chambers at an acute angle relative to the plane of the rim of said respective inner chamber.