Abstract: Printing apparatus particularly suited to a cash register includes a hammer arranged to move printing paper into engagement with type wheels located on the other side of the paper. A cam and linkage move the hammer into and out of contact with the paper. Strong springs are provided to rapidly accelerate the hammer toward the paper through an engaging plate. The engaging plate is stopped before the hammer contacts the paper, and the hammer strikes the paper due to its inertia. The hammer rebounds off the paper and is caught and held by the linkage in the rebound position between the paper and the engaging plate to prevent double printing.