Chemical ratio feed pump

Claim 1

A TREATING FLUID FEED PUMP OF THE CHARACTER DESCRIBED COMPRISING: A PRESSURE FLUID CYLINDER; SAID PRESSURE FLUID CYLINDER CONTAINING UNIDIRECTIONAL INLET AND OUTLET VALVES OPERATED BY A VALVE OPERATING LEVER; A CAM OPERATING AGAINST SAID VALVE OPERATING LEVER TO ALTERNATELY SUPPLY AND EXHAUST PRESSURE FLUID THROUGH SAID VALVES TO SAID CYLINDER; MEANS TO ROTATE SAID CAM; A PUMP HEAD CHAMBER HAVING INLET AND OUTLET VALVED PASSAGEWAYS TO PREVENT REVERSE FLOW; A FLEXIBLE DIAPHRAGM MEMBER DISPOSED IN SAID PUMP HEAD CHAMBER, ONE SIDE OF WHICH IS IN COMMUNICATION WITH SAID PASSAGEWAY TO MOVE TREATING FLUID THERETHROUGH; A PISTON DISPOSED IN SAID PRESSURE FLUID CHAMBER OPERABLE UPON SUPPLY OF PRESSURE FLUID TO STROKE IN ONE DIRECTION; A RECIPROCABLE OPERATING SHAFT SEALED WITH RESPECT TO SAID CYLINDER AND INTERCONNECTING SAID PISTON AND SAID DIAPHRAGM ON ITS OTHER SIDE, A CONDUIT THROUGH SAID SHAFT TO PROVIDE COMMUNICATION OF SAID PRESSURE FLUID WITH THE OTHER SIDE OF SAID DIAPHRAGM; A RETURN SPRING TO BIAS SAID PISTON IN AN OPOSITE DIRECTION UPON EXHAUST OF SAID PRESSURE FLUID; A CONTROL STOP MEMBER CONTIGUOUS TO THE END OF SAID PISTON STROKE IN SAID OPPOSITE DIRECTION; AND A CONTROL CAM ADJUSTABLY SECURED TO SAID CYLILNDER AND OPERABLE TO DISPLACE SAID STOP MEMBER WITH RESPECT TO SAID PISTON AND THEREFORE SET THE DESIRED LENGTH OF SAID STROKE.