Abstract: An air-driven pump includes a source of compressed air, a vacuum source including a venturi and two pump units with structurally independent pumping elements dividing pump chambers from air chambers. A directional control valve is in communication with the source of compressed air, the vacuum source, the pump unit air chambers. The directional control valve includes two valve positions alternating communication of the source of compressed air and the vacuum source with the air chambers. A pilot valve system shifts the directional control valve between the two valve positions at end of stroke positions of the pump and includes actuators extending into the air chambers to engage the pumping elements with the air chambers contracted.

Abstract: An elongate air operated pump includes a pump chamber, a bladder inside the pump chamber, inlet and outlet valves to and from the chamber and an air control system. The air control system includes a control valve alternately communicating compressed air and exhaust to atmosphere to a venturi with a first end, a second end and a throat port. The first end of the venturi receives continuous compressed air. The second end receives the alternately communication of compressed air and exhaust to atmosphere from the control valve. The throat port of the venturi is in continuous communication with the bladder to pressurize and draw a vacuum on the bladder. The valves may be pneumatic pinch valves controlled by the control valve to cycle with the bladder or passive one-way pump valves.

Abstract: An air-driven pump includes a source of compressed air, a vacuum source including a venturi and two pump units with structurally independent pumping elements dividing pump chambers from air chambers. A directional control valve is in communication with the source of compressed air, the vacuum source, the pump unit air chambers. The directional control valve includes two valve positions alternating communication of the source of compressed air and the vacuum source with the air chambers. A pilot valve system shifts the directional control valve between the two valve positions at end of stroke positions of the pump and includes actuators extending into the air chambers to engage the pumping elements with the air chambers contracted.

Abstract: An elongate air operated pump includes a pump chamber, a bladder inside the pump chamber, inlet and outlet valves to and from the chamber and an air control system. The air control system includes a control valve alternately communicating compressed air and exhaust to atmosphere to a venturi with a first end, a second end and a throat port. The first end of the venturi receives continuous compressed air. The second end receives the alternately communication of compressed air and exhaust to atmosphere from the control valve. The throat port of the venturi is in continuous communication with the bladder to pressurize and draw a vacuum on the bladder. The valves may be pneumatic pinch valves controlled by the control valve to cycle with the bladder or passive one-way pump valves.