| 摘要 |
PURPOSE:To render cassette exchange operation, etc., unnecessary in an electrophotographic copying machine reading a cassette mark, judging a sheet size, and controlling the peripheral length of a photosensitive drum to be electrostatically charged, by using the max. peripheral length to be charged corresponding to the max. sheet size at the time of manual insertion of the sheet. CONSTITUTION:When a cassette 12 is inserted into the main body of a copying machine, Hall elements S1.S2 sense the magnet M of the cassette 12, and detect the size of the sheet (a) of each cassette, and the charging length of the drum is controlled. The sheet size is fixed dependent on the kind of a cassette. When the cover 24 of the cassette 12 is slid and inserted between the sheet (a) and the sheet feed roller 13, switches in the main body sense the magnet M1, and the mode is changed to a manual insertion mode. The manual insertion is made possible from above the cover 24, and at the same time, the charging length is changed to one corresponding to the max. sheet size. |
