Patent ID: 7331403

Claim:
A power tool comprising: a structure; a flywheel coupled to the structure; a driver; an activation arm assembly having a first arm, a second arm, a third arm and a roller, the third arm carrying the roller and being pivotally coupled to the second arm, the second arm being pivotally coupled to the first arm, the first arm being pivotally coupled to the structure; and a bar coupled to the structure and movable between an extended position and a retracted position; wherein the activation arm assembly is movable between a first position, in which the roller does not initiate frictional engagement between the flywheel and the driver, and a second position, in which the roller pushes the driver into engagement with the flywheel; and wherein the bar contacts the activation arm assembly when the bar is positioned in the extended position to inhibit the activation arm assembly from being moved from the first position to the second position, and wherein positioning of the bar in the retracted position disengages the bar from the activation arm assembly to permit the activation arm assembly to be moved from the first position to the second position.