| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method for checking a thermal head capable of preliminarily warning of deterioration of the thermal head, before a thermal head gets deteriorated or damaged to the extent not to be usable for printing so that a necessary printing operation can be executed according to intention of a user until the thermal head finally becomes unusable, and to provide a checking unit. <P>SOLUTION: In this method, deterioration of a thermal head is detected in at least two stages such that the resistance value of a heat generating member of the thermal head is compared with a first resistance value and a second resistance value successively, and while the resistance value shows a level in-between, it is judged that a printing operation can be executed. A first warning step of warning of deterioration of the thermal head in the case the resistance value of the heat generating member exceeds the first resistance value, and a second warning step for indicating that the thermal head is unusable in the case the resistance value of the heat generating member exceeds the second resistance value, which is higher than the first resistance value, are provided. <P>COPYRIGHT: (C)2004,JPO</p> |
