Abstract: A fluid driven pump. One embodiment of the fluid driven pump may include first and second diaphragms supported within a housing assembly such that first and second fluidtight expansion chambers are defined within the housing. The pump may have a first exhaust valve movably supported in a first exhaust valve cavity in fluid communication with the first expansion chamber and an exhaust port in the housing assembly. In addition, the pump may have a second exhaust valve movably supported in a second exhaust valve cavity in fluid communication with the second expansion chamber and the exhaust port. A flow control system may be supported by the housing assembly and be couplable to a source of pressurized control fluid.

Abstract: A fluid driven pump includes an inlet, at least one expansion chamber for expanding upon introduction of fluid thereinto and contracting upon removal of fluid therefrom, a pumping chamber adjacent the expansion chamber for pumping in response to the expansion chamber's expansion and contraction, and an outlet for outletting pressurized fluid from the expansion chamber. A control system controls a flow of fluid from the inlet to the expansion chamber and a flow of pressurized fluid from the expansion chamber to the outlet. The outlet includes structure for gradually reducing the pressure of the fluid within a portion of the outlet to reduce blockage of the outlet due to freezing.