Control system for an air operated diaphragm pump

1. A pump including

a housing defining a chamber,

a pump member separating the chamber into a pumping side and a pumped side, the pump member moving from a first position to a second position forcing fluid from the pumped side of the chamber,

a supply valve controlling the flow of pressurized fluid to the pumping side of the chamber, the pressurized fluid moving the pump member from the first position to the second position, and

a controller operably coupled to the supply valve to control movement of the supply valve between an open position and a closed position based on non-electric feedback, the controller moving the supply valve to the closed position for at least a portion of the time that the pump member moves from the first position to the second position.

2. The pump of claim 1 , wherein the controller includes a pressure regulator.

3. The pump of claim 1 , wherein the controller includes a variable restriction controlling the portion of time that the supply valve is closed.

4. The pump of claim 1 , wherein the supply valve is air-piloted by the controller.

5. The pump of claim 1 , further comprising a sensor that provides the non-electric feedback to the controller.

6. The pump of claim 1 , wherein the non-electric feedback is pneumatic and the controller provides a pneumatic signal to the supply valve.

7. A pump including

first and second diaphragm chambers, each diaphragm chamber including a diaphragm, the diaphragms being coupled together,

a pressure sensor positioned to detect a pressure in at least one of the first and second diaphragm chambers and to output a fluid signal relating thereto, and

a controller devoid of electrical inputs configured to receive the fluid signal from the pressure sensor and monitor the pressure to detect the position of at least one of the diaphragms.

8. The pump of claim 7 , further comprising an air supply valve positioned to control the flow of pressurized air to the first and second diaphragm chambers, the controller communicates with the air supply valve to control the flow of pressurized air based on the fluid signal received from the pressure sensor.

9. The pump of claim 8 , further comprising a main valve in fluid communication with the air supply valve, wherein the main valve alternates between a first position supplying air to the first diaphragm chamber and a second position supplying air to the second diaphragm chamber.

10. The pump of claim 9 , wherein the air supply valve supplies pressurized air to the main valve for a predetermined amount a time and blocks pressurized air from flowing to the main valve for another amount of time.

11. The pump of claim 7 , wherein the fluid signal from the pressure sensor is pneumatic.

12. The pump of claim 7 , wherein the pressure sensor includes a pressure regulator.

13. A pump including

first and second diaphragm chambers, each diaphragm chamber including a diaphragm, the diaphragms being coupled together,

a main valve configured to supply pressurized air to the diaphragms,

a pilot valve configured to move the main valve between a first position and a second position, and

a controller configured to control the supply of pressurized air to the pilot valve and the main valve based on the position of at least one of the diaphragms, the controller being devoid of electrical inputs.

14. The pump of claim 13 , further comprising an air supply valve controlled by the controller and positioned to supply pressurized air from an air supply to the first and second diaphragm chambers.

15. The pump of claim 14 , wherein the controller communicates with the air supply valve and provides pressurized air to the first and second diaphragm chambers for a predetermined time based on the controller detecting a position of at least one of the diaphragms, and restricts pressurized air at other times.

16. The pump of claim 13 , further comprising a pressure sensor positioned to detect air pressure in at least one of the chambers, wherein the pressure sensor provides a pneumatic signal to the controller based on the pressure in the at least one chamber.