Patent ID: 8550179

Claim:
A control system for use in conjunction with a primary power system, the primary power system operable to power a hand-held tool, and the control system operable to control the amount of power to the tool, the control system comprising: an air delivery assembly including a first supply line of pressurized air in fluid communication with the primary power system; a control assembly including an exhaust line from the primary power system and to the control assembly, a spool valve having a spool containment body and a spool housed within the body operable to move freely along at least a portion of a length of the body, said spool valve being in fluid communication with the first supply line and the exhaust line, wherein the spool containment body has a metering slot formed along a portion of its length, such that air can be exhausted out of the body upon proper alignment of the spool valve with the metering slot, wherein a shape of the metering slot has no more than one axis of symmetry; a control line in fluid communication with the spool valve and the hand-held tool; and a second supply line of pressurized air in fluid communication with the primary power system and the hand-held tool.