Patent ID: 7594547

Claim:
A power tool comprising: a frame; a flywheel mounted to the frame; a nosepiece coupled to the frame; a driver received in the nosepiece and disposed proximate the flywheel; an activation arm assembly having a first arm, and a roller, the first arm being mounted to the frame and pivotable about a first pivot axis, the roller being coupled to the first arm and movable with the first arm between a first position and a second position in which the roller drives the driver into frictional engagement with the flywheel to transmit energy from the flywheel to the driver to cause the driver to move along a translation axis; a contact trip coupled to the nosepiece and movable between an extended position and a retracted position; and a stop mechanism having a wedging member and an arm, the wedging member being movable between a first wedge position and a second wedge position, the arm being configured to move the wedging member between the first and second wedge positions in response to movement of the contact trip between the extended position and the retracted position, respectively, wherein the wedging member is disposed in a rotational path of the first arm when the wedging member is positioned in the first wedge position to thereby inhibit the roller from being moved with the first arm into the second position, and wherein the wedging member is disposed out of a rotational path of the first arm when the wedging member is positioned in the second wedge position to thereby permit the roller to be moved with the first arm into the second position.