Patent ID: 8436881

Claim:
An image formation apparatus comprising: a thermal head on which a plurality of heat elements are arranged to form an image on a recording medium; a platen provided opposite the thermal head to pass the recording medium between the platen and the thermal head; a contact/separation unit configured to contact/separate the thermal head and the platen with/from each other via the recording medium; a capstan that transfers the recording medium; a pinch roller provided opposite the capstan to pass the recording medium between the pinch roller and the capstan; and a pressing force application unit configured to exert a pressing force to press the capstan and the pinch roller against each other via the recording medium, wherein, the capstan includes a plurality of projections on a pressing surface of the capstan that presses the recording medium, a height of each of the projections from the pressing surface is defined as H, and the height H is in a range of 20 μm<H≦40 μm, the pressing force application unit includes a pair of fixation springs and a pair of adjustment springs provided at both ends of the pinch roller to urge the pinch roller toward the capstan, one fixation spring and one adjustment spring being respectively provided at each end of the pinch roller, and each of the adjustment springs is coupled to the thermal head so as to produce a smaller spring force when the contact/separation unit establishes no contact between the thermal head and the platen than the spring force produced when the contact/separation unit establishes the contact between the thermal head and the platen.