| 摘要 |
PURPOSE:To perform preheating within the capacity of power source necessary for drive by providing a preheating period setter in which preheating period to impose overload to an electric wire is regarded as a non-drive period for a thermal head for a facsimile, etc. CONSTITUTION:During the period when recording is made on 1st paper in the time periods t11-t12 and on 2nd paper in the time periods t13-t14, a signal 5 to selectively drive a thermal head 1 is outputted. On the other hand, when the temperature of the base plate of the head 1 is lowered beyond a given value, a temperature controller 14 sends out a preheating lowering detection signal 16 and also a print controller 11 sends forth a recording stop period signal 17 representing the period when the signal 5 is not outputted. A preheating controller 13 sends out a preheating start signal 18 on the basis of the AND of both signals and a preheating current 8 is flowed in the varister of the head 1 for the preheating period T. The current flows in too much amounts in the early period to lower the voltage V of the power source 4 but returns to its original state within the period T. Thus, better recording can be made by effectively utilizing the power source without the use of preheating power source. |
