US Patent 7942298 Paper processing tool with force reducing drive arrangement

A stapler includes a base member, a magazine for receiving a plurality of staples, and a drive member including a driver blade movable relative to the magazine for ejecting staples from the magazine one at a time. The stapler further includes an input member pivotally coupled to the drive member. The input member is configured to receive an input force and transmit the input force to the drive member for driving movement of the drive member relative to the magazine. One of the drive member and the input member pivots about a pivot axis that moves relative to the base member along an arcuate path.