Patent ID: 6011945
Filing Date: 2000-01-04
Classification: G03G

Abstract:
An electrophotographic printer comprising:a photosensitive drum sensitized with a first image and a second image to be printed respectively on one side and the other side of a sheet;a first transfer roller for transferring the first image from said photosensitive drum to the one side of the sheet as said first transfer roller rotates while contacting said photosensitive drum;a second transfer roller for transferring the second image, which is transferred from said photosensitive drum to said second transfer roller via said first transfer roller, to the other side of the sheet; anda sheet-feeding roller for supplying the sheet into a nip defined between said first and said second transfer rollers;wherein said first and said second transfer rollers continuously define the nip during the transfer of the first and the second images from said photosensitive drum to the sheet;wherein said second transfer roller has a circumference which equals a total length of the sheet plus one half a circumference of said first transfer roller;wherein the sheet is supplied into the nip defined between said first and said second transfer rollers by said sheet-feeding roller after the second image for the other side on said photosensitive drum is transferred to said second transfer roller via said first transfer roller, so that the second image for the other side on said second transfer roller is transferred to the other side of the sheet and simultaneously the first image for the one side on said photosensitive drum is transferred to the one side of the sheet via said first transfer roller; andwherein the size of the sheet is selected from the group consisting of A3, A4, A5, legal, and letter.