PURPOSE: To prevent the entry of the combustible solvent for toner development into an electrostatic charging part without any flaw, unevenness and contamination on a machine plate even after long-term use, by flowing air having prescribed temp. and humidity to at least the electrostatic charging part and/or exposing part of an engraver.
CONSTITUTION: A cooling mechanism 22, a heating mechanism 23 and a blower fan 24 are provided to a temp./humidity control part 1, and the air controlled to prescribed conditions is fed to a presetting part 2 and an electrostatic charging part 3 to control the temp. and/or humidity thereof. The air flows out through the slit 19 in a delivery port for engraving material so that the temp. and humidity in an exposing part 4 can be substantially controlled by said air. A developing part 5 is substantially isolated by the control of the electrostatic charging part, whereby the intrusion of the evaporated solvent thereof into a corona charging part 2 and the explosion thereof are prevented. The device is so arranged that the air flows successively through the presetting part, the part 3, the exposing part, the developing part, etc., and it is equally well to arrange the same so as to feed the air separately to the respective parts.
KUNICHIKA KENJI
YAZAWA HIROMI
