Patent ID: 8292143

Claim:
A fastener driving device comprising: a housing having an engine receiving portion; a drive engine located in the engine receiving portion, the drive engine comprising a cylinder and a piston reciprocally mounted within the cylinder, the piston comprising a driver configured to move along a drive axis to drive a fastener during a drive stroke; a nose assembly operatively connected to the housing, the nose assembly comprising a drive track aligned with the drive axis; a magazine constructed and arranged to feed successive leading fasteners from a supply of fasteners into the drive track; a pusher assembly slidably mounted in the magazine, the pusher assembly comprising a pusher configured to push the supply of fasteners towards the drive track, and a lifter comprising a dry fire lockout portion; a trigger configured to operate the drive engine; a contact trip assembly comprising a lower contact arm comprising a first end configured to contact a work piece, an upper contact arm comprising a first end operatively connected to the lower contact arm, and a second end configured to enable the trigger to operate the drive engine, a link movably mounted to the first end of the upper contact arm and interconnected with the lower contact arm when the link is in a first orientation, the link comprising a dry fire lockout portion, and a biasing member positioned between the link and the upper contact arm, the biasing member being configured to bias the link in the first orientation so that the link is interconnected with the lower contact arm to operatively connect the link and the lower contact arm; wherein the dry fire lockout portion of the lifter is configured to engage the dry fire lockout portion of the link, when the supply of fasteners is less than a predetermined number of fasteners, and move the link against the bias of the biasing member to a second orientation in which the link is not interconnected with the lower contact arm.