Patent ID: 8360745

Claim:
An air driven pump comprising an actuator including operatively opposed air chambers, an air valve in communication with the air chambers, an intake having an intake passage, wherein the intake passage extends to the air valve, an intake adjuster having a closure element, wherein the closure element is operatively mounted in the intake to move axially into and out of the intake passage with angular rotation of the intake adjuster to selectively restrict an air flow rate in the intake passage, a ratio of an axial advancement of the closure element to angular rotation of the intake adjuster decreasing as the intake passage is progressively restricted by the closure element, the intake adjuster further having a first angular position when the intake passage is at a maximum selected restriction, and a second angular position when the intake passage is at a minimum selected restriction, changes in the air flow rate through the intake passage being equal for equal incremental angular rotation of the intake adjuster between the first angular position and the second angular position; at least one variable volume pump chamber; and a pumping element driven by the operatively opposed air chambers.