Patent ID: 7283147

Claim:
A printer comprising: a frame having a pair of side walls; a head support member holding a thermal head; a platen roller rotatably supported on the pair of side walls; a plurality of elastic members arranged along a longitudinal direction of the head support member to bring the thermal head into contact with a peripheral surface of the platen roller under predetermined loads; and a feeding mechanism which feeds an unwound part of a printing medium while positioning a side edge of the unwound part near one end of the thermal head according to a width of the printing medium selected from among a plurality of printing media having different widths, wherein the predetermined loads by the plurality of elastic members are determined such that a load exerted on the one end of the thermal head is larger than a load exerted on the other end of the thermal head, and wherein a resultant force of the plurality of elastic members acts on a position displaced by a distance obtained by multiplying an entire length of the thermal head by a value in a range of 0.004 to 0.029, the distance measured from a center of the thermal head in the longitudinal direction toward the one end of the thermal head.