Patent ID: 7551191

Claim:
A thermal transfer printing apparatus comprising: a lever member which displaces at least one of a thermal head and a platen roller so that the thermal head and the platen roller come close to each other or come away from each other; and a driving unit for operating the lever member, wherein the driving unit includes a rotary member having a rotary center shaft in a direction crossing a conveying direction of a recording medium and a roller shaft direction of the platen roller, wherein the rotary member is disposed in a conveying width region of the recording medium, wherein the rotary member includes cams which rotate the lever member, wherein the driving unit includes worm gears which transmit rotation forces to the cams, and wherein rotary center shafts of all rotary members constituting the driving unit except rotary center shafts of the worm gears are arranged in a direction crossing a conveying direction of the recording medium and a roller shaft direction of the platen roller, and are arranged in a conveying width region of the recording medium.