| 摘要 |
PROBLEM TO BE SOLVED: To prevent a transfer defect from occurring even when a transfer material, for example, small-size paper is passed in the case of constant current control by detecting the width of the transfer material, calculating a current relieved to a paper non-passing part and changing a transfer current according to a function. SOLUTION: By a controller, the kind of the paper which is used is detected as a parameter according to the type of a paper cassette which is used for a paper supply part. Based on the detected kind of the paper, the width of the paper is found through a conversion table. Or it is directly found, based on the position of a manual feeding guides. Next, the transfer current is calculated by the controller, based on paper size and the conversion expression of the optimum transfer current. The optimum transfer current of every size calculated by the controller is transferred to the constant current control circuit of a high-voltage power source 29 as a PWM signal. By controlling an intermediate transfer body 5 using this current at a secondary transfer time, an excellent transfer action can be executed even when the paper of any size is used. |
