| 摘要 |
PROBLEM TO BE SOLVED: To obtain an image forming device capable of preventing a faulty image caused by faulty attraction even in the case of vertical orbit transfer belt by excellently attracting transfer material to the transfer belt regardless of service environment or a printing mode. SOLUTION: The transfer belt 8 takes a vertical rotary orbit and four image forming stations PY to PK are arranged in a vertical direction along the rotary orbit. Paper as the transfer material is electrostatically attracted on an upstream side in the carrying direction of the belt 8 by an attraction roller 7 arranged thereon, and successively carried to the stations PY to PK by the belt 8, whereby respective color toner images formed on photoreceptor drums 11 to 14 are multiply transferred by transfer rollers 51 to 54. In order to firmly attract and carry the paper on the belt 8 under all the environment from a high- temperature and high-humidity state to a low-temperature and low-humidity state and also at the time of automatic both-sideprinting, attraction bias from an attraction high voltage power source is changed and controlled and applied to the roller 7 so as to obtain the attractive force of about 20 gf/cm2. |
