| 摘要 |
PURPOSE:To prevent surely condensation in a copying machine with low electric power consumption by detecting external humidity in addition to the internal and external temps. of the copying machine, and controlling automatically the operation of a heater for preventing condensation from the values of said temps. and humidity. CONSTITUTION:An internal temp. t1 and external temp. t2 are detected by an internal temp. sensor 1 and an external temp. sensor 2 for a copying machine and the humidity h2 at the temp. t2 is determined by a curve S2 passing through the point C of 100% humidity under the satd. steam pessure S2 at the temp. t1. On the other hand, the actual external humidity (h) of the copying mahcine is measured by a sensor 3 for detecting the external humidity of the copying machine and the humidities (h) and h2 are compared by a comparator 4. A heater 6 for preventing condensation installed in the copying machine is operated by a control device 5 when h>=h2 or h-h2>=c (c is a constant), by which the condensation in the copying machine is prevented. |
