| 摘要 |
<p>PURPOSE:To speedily detect dew condensation on a cylinder head of VTR and to improve the accuracy of the printing size of an electrode by providing a couple of electrodes on an electric insulating film on a metal plate and covering the electrode with a humidity sensing film. CONSTITUTION:The metallic plate 1 which has good heat conductivity has nearly the same heat capacity with the cylinder head of VTR, so when dew condensation is caused on the cylinder head, drops of dew are formed on the metal plate 1. The humidity sensing film 5 absorbs the water and its resin swells, so conductive particulates in the resin separate from one another and the electric resistance value between the couple of electrodes 4 increase, so the dew condensation on the cylinder head of VTR can be detected from the output of a lead line 6. Further, the metallic plate 1 is used as the substrate of a humidity sensor, which is fixed strongly to the metallic plate 1 with screws, thereby improving the accuracy of the printing size of the electrode 4.</p> |
