Copier capable of setting up an erase area on a photoconductive element

Claim 1

In a copier which forms a latent image on a photoconductive element and which is responsive to various sized papers wherein the direction in which the papers are fed is assumed to be a direction x and a direction perpendicular thereto a direction y, said copier comprising: paper size detector means for sensing a paper size (Px, Py) representative of the size of the papers; document size detector means for sensing a document size (Ox, Oy) representative of a size of the documents being copied; trimming area detector means for sensing a trimming area size (Tx, Ty) representative of an area size after trimming; magnification detector means for sensing a magnification R selected; and eraser means for erasing needless electrostatic latent images formed on the photoconductive element; a means for determining the overlapping length of said Px, Ox X R and Tx X R selected in accordance with a length of a non-erase area in the direction x, an overlapping length of said Py, Oy X R and Ty X R selected in accordance with a length of the non-erase area in the direction y, whereby said erase means erases the latent images outside of the non-erase area.