Abstract: A nut running air tool improved with a back and forth manually slidable control valve located between a throttle valve and an air motor, the control valve having a forward position allowing full volume air flow to the motor and maximum forward torque output, a reverse position allowing full volume air flow to the motor and maximum reverse torque output, and the control valve having integral manipulative means for adjusting its effective length so as to permit it to be moved to a third position allowing a restricted volume air flow to the motor and restricted forward torque output.

Abstract: Safety air valve control arrangement for feeding inlet air to the motor of a rotary hand held tool, such as an impact wrench, and guarding against accidental feeding of such air, as when the tool is carelessly rested or dropped, the control arrangement comprising a manipulative lever operated throttle valve and a manipulative trigger operable safety valve both of which must be separately manually operated and held at the same time in operated condition to enable inlet air feed to the motor. Release of either valve to closed condition will shut off operation of the tool.

Abstract: Overspeed safety control mechanism for shutting off operating air flow to the motor of a rotary surface grinding tool when the motor overspeeds beyond a rated governed maximum, including a circular body rotatable with the motor and carrying a ball valve which is adapted to be centrifugally released and entered into a pocket to block flow of operating air to the motor when the latter overspeeds, the speed of the motor being normally controlled by a speed governor.