Dot line printer having ordinary low dot and high dot density printing modes

A dot line printer for printing dot images on a printing sheet comprising:

• a hammer bank comprising a plurality of print hammers arrayed in a shuttling direction, the hammer bank being reciprocally movable in the shuttling direction;
• means for moving the printing sheet in a line to line direction;
• a shuttling mechanism for moving the hammer bank in the shuttling direction, the shuttling mechanism comprising a shuttle motor and a cam mechanism drivingly connected to the hammer bank and having a shuttle cam driven by the shuttle motor, said shuttling mechanism moving the hammer bank through a printing region where the print hammers move toward the printing sheet for printing and a reversing region where the moving direction of the hammer bank is reversed and the print sheet is fed in the line to line direction, the hammer bank and the shuttling mechanism providing a first dot density printing mode having a first dot density and a second dot density printing mode having a second dot density less than the first dot density, wherein the shuttle motor rotates in the printing region at a first angular velocity in the first dot density printing mode and in the second dot density printing mode the hammer bank has a moving velocity greater than in the first dot density printing mode and the shuttle motor rotates in the printing region at a second angular velocity which is greater than the first angular velocity,
• wherein the shuttling cam has cam profile means for providing a predetermined reversing period for reversing the hammer bank when the shuttle motor is rotated at a predetermined third angular velocity which is in the range between the first and second angular velocities, and
• wherein the shuttle motor accelerates and decelerates the hammer bank for providing the predetermined reversing period during a reversing operation in both the first and second dot density printing modes.