| 摘要 |
PURPOSE:To prevent or eliminate dew condensation on an optical system associated with environmental change inside and outside a device by simultaneously driving both a fan and a dehumidification resistance for a specified time in accordance with the suspension period of a copying machine. CONSTITUTION:The fan 10 for cooling the optical system and the dehumidification resistance 8 which are ordinarily installed in the copying machine are used and the resistance 8 is positioned in front of the fan 10, that is, between the optical system 11 and the fan 10. When the copying machine works again after it is used for a long time and is suspended, both the fan 10 and the resistance 8 are turned on in the warm-up period of the copying machine. Thus, air warmed by the resistance 8 is allowed to blow against the lens and the mirror of the optical system 11 by the fan 10 n the manner of what is called a hot air drier and such parts of the optical system 11 are properly heated by hot air. Therefore, even when the copying machine gets in a 'copying performable' state thereafter and the sudden change of environmental circumstances associated with lighting a copying lamp is caused, the dew condensation is not caused in the optical system 11, faulty copying is prevented from occurring, and image quality which satisfies a user is guaranteed. |
