Patent ID: 9574554
Date: 2017-02-21
CPC Classifications: F04B

Claim:
1. A pump including: a housing defining a pair of chambers; a first pump member separating one of the chambers into a pumping side and a pumped side, the first pump member being movable between a first position and a second position, thereby forcing fluid from the pumped side of the one chamber; a second pump member separating another of the chambers into a pumping side and a pumped side, the second pump member being movable between a first position and a second position, thereby forcing fluid from the pumped side of the other chamber; an air piloted supply valve in flow communication with a supply of pressurized fluid, the supply valve being movable between an opened position wherein pressurized fluid flows to the pumping side of one of the chambers, and a closed position wherein pressurized fluid is inhibited from flowing to either of the chambers, the supply valve having a first port in flow communication with the supply of pressurized fluid and a second port; and a mechanical controller including a pressure regulator having an input in flow communication with the supply of pressurized fluid and an output in flow communication with the second port of the supply valve; wherein after the supply valve has been in the opened position for a period of time, the output of the pressure regulator provides pressurized fluid to the second port of a sufficient pressure to move the supply valve to the closed position.