Patent ID: 7762347

Claim:
An impact power tool for use in delicate hand working operations, said impact power tool comprising: an air delivery system operable to communicate with an air source; a hand held device in driven communication with the air delivery system; and a drive assembly operable to selectively and variably control the hand held device, the drive assembly including— a motor, and a valve drivingly coupled with the motor and operable to communicate with the air source, the valve including— an exhaust port comprising a first elongated slot, an intake port having a height and a width, an output port, and a rotor having a body operable to rotate within said valve and at least one port extending diametrically through the body to intermittently communicate with the exhaust port, the intake port, and the output port, said rotor port including a second elongated slot presenting approximately the same area and configuration as the first elongated slot of the exhaust port, wherein during rotation of said rotor within said valve, said second elongated slot of the rotor port cycles through alignment with said first elongated slot to provide intermittent pulses of air, each of said first and second elongated slots having a major dimension and a minor dimension, said major dimension of the first elongated slot being approximately 90%-150% the major dimension of the second elongated slot, said height of the intake port being approximately 90%-150% the major dimension of the second elongated slot, said width of the intake port being at least greater than the minor dimension of the second elongated slot.