A nail-driving device has a housing, a trigger unit, a safety unit, a connecting unit and a magazine. The safety unit has first and second safety members in the housing. The connecting unit is connected pivotally to the second safety member, and has a retaining portion disposed movably between the first and second safety members. The magazine has a pusher for pushing nails therein. When the retaining portion is in a retaining position, a force is applicable to the first safety member to move the second safety member to pivot a trigger arm for a nail-driving operation when the trigger unit is actuated. When the nails thereof are exhausted, the pusher moves to a retention releasing position to pivot the connecting unit and remove the retaining portion from the retaining position to allow for relative movement of the first and second safety members to prevent the nail-driving operation.
A safety is incorporated in a nailing device, which ensures operation safety of the nailing device. The nailing device includes a housing containing a striker plate movable to a ready-to-strike position for subsequently striking a nail. The safety includes a retainer having an inclination engageable with a mated inclination formed on a release plate that is normally biased to partially project out of the housing, so that a stop of the retainer is set at a position to block the striker plate from moving toward the ready-to-striker position. When the nailing device is properly set on a work piece, the release plate is forced by the work piece back into the housing and the retainer is rotated by the camming action between the mated inclination faces so as to move the stop aside to allow the striker plate to move to the ready-to-strike position.