| 摘要 |
PURPOSE:To prevent the generation of dew condensation, by controlling the supply of a current to a thermo-module on the basis of the output of a sensor for detecting the temp. of a substrate having the heat generating element of a thermal head arranged thereto and the output of a sensor for detecting the temp. in an apparatus so as to make the temp. in the apparatus approximate to that of the substrate. CONSTITUTION:The supply of a current to a thermo-module 32 is controlled by a control circuit 34 so that the temp. of a substrate becomes almost equal to that in an apparatus. When the driving of a recording apparatus is started and the heat generating element 30 of a thermal head 20 generates heat, a part of said heat is lost by recording and the remainder thereof heats the substrate 28. The output of a temp. sensor 36 detecting the temp. of the substrate is compared with that of a sensor 37 detecting the temp. in the apparatus and, when the rising in the temp. of the substrate 28 is shown, the supply of a current to the thermo-module 32 is started by the control circuit 34 and the substrate 28 is cooled to the temp. in the apparatus. The opposite side surface of the thermo-module 32 is heated to temp. higher than that in the apparatus, but the heat is radiated by fins 32 to cool said surface. Since said cooling effect can be continued at a high level until the temp. of the substrate 28 reaches that in the apparatus, the rising in the temp. of the substrate 28 generated by the driving of the heat generating element 30 is rapidly and certainly prevented. |
