| 摘要 |
The present invention provides a method and an apparatus for driving and controlling a thermal head used in a printing device, such as a tape printer, in response to the temperature variations of the environment and the thermal head. In the printing operation of the printing device, measurements are made of the initial temperature T1 immediately after the power is switched on, the temperature T2 prior to printing, and the ambient temperature T3(i) of the thermal head each time the thermal head prints. If the temperature difference between the temperature T1 and the temperature T2 is small, the duration of the current signals provided to the thermal head is controlled in accordance with the temperature T2. If the difference is large, the duration is controlled in accordance with the temperature T1. If the rate of the increase in temperature T3(i) during printing is large, the duration is controlled in accordance with the initial temperature T2 to reduce the duration. If the temperature T3(i) exceeds a temperature which indicates over-heating, the printing operation is aborted. Thus, the present invention allows for controlling the thermal head drive by means of the ambient temperature which is not affected by the heat generation of the thermal head and in accordance with the thermal state of the thermal head. <IMAGE>
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