Patent ID: 8137014
Filing Date: 2012-03-20
Classification: B41J

Abstract:
1. A duplex printing apparatus for printing images on a first side and a second side of a paper, said duplex printing apparatus comprising: a paper input tray for placing said paper thereon; a paper ejecting tray disposed above said paper input tray for supporting said printed paper thereon; a scanning and developing print unit disposed in a print region for reading said images and printing said images on said paper; a paper feeding channel arranged between said paper input tray and said print region for leading said paper to said print region such that said images are printed on said first side of said paper when said paper is transported across said print region; a paper pick-up roller disposed beside said paper input tray for transporting said paper into said paper feeding channel; a paper ejecting channel arranged between said print region and said paper ejecting tray for leading said paper to said paper ejecting tray; an inverting channel arranged between said print region and said paper ejecting tray for leading said paper to said print region again such that said images are printed on said second side of said paper when said paper is transported across said print region; a first paper transfer roller assembly arranged at the junction between said paper feeding channel and said inverting channel for transporting said paper into said print region; a second paper transfer roller assembly disposed in said paper ejecting channel for transporting said paper; a third paper transfer roller assembly disposed in said inverting channel for transporting said paper to into said print region; and a paper ejecting roller assembly for transporting said paper to either said paper ejecting tray or said inverting channel.