Patent ID: 7791627

Claim:
A printer comprising: a thermal head which transfers ink applied to an ink ribbon onto a recording medium, thereby printing print data, a platen which is located opposite the thermal head and conveys the ink ribbon and the recording medium between the platen and the thermal head, a ribbon supply shaft which supports an ink ribbon supply roll, a ribbon take-up shaft, which supports an ink ribbon take-up roll, and on which the ink ribbon is wound up after printing, a stepping motor for a ribbon take-up shaft drive which drives the ribbon take-up shaft, a tension arm located in a ribbon path between the thermal head and the ribbon take-up shaft in a manner such that the tension arm is urged in a loosening direction of the ribbon, and a detector for detecting a displacement of the tension arm, in which the stepping motor for the ribbon take-up shaft drive is stopped or driven according to an output of the detector, wherein if the detector determines that the ink ribbon is loose, the stepping motor for the ribbon take-up shaft drive is initially driven at a predetermined speed, if the detector determines that the ink ribbon remains loose after a first predetermined time interval starting from the start of the stepping motor, the stepping motor continues operating at current stepping motor speed, if the detector determines that the ink ribbon remains loose after a second predetermined time interval starting from the start of the stepping motor, the speed of the stepping motor is increased, alternatively, if the detector determines that the ink ribbon is in tension, the stepping motor is stopped until the detector next determines that the ink ribbon is loose.