Abstract: A paper feeder capable of preventing a sheet of paper from breaking when a paper jam is developed within an image forming apparatus over the boundary between a paper conveying unit and the image forming apparatus and simply removing the jammed paper outside from the paper feeder. An entrance roller pair for feeding the paper is provided in the neighborhood of an entrance of a paper conveying path. A lower fixed guide member and a rotatable guide member opposed to each other so as to interpose the paper conveying path therebetween, are provided on the downstream side as seen in a paper feeding direction. Further, a jump portion which projects in convex form at a position opposed to the rotatable guide member and a paper sensor for detecting a rear end of the paper in the neighborhood of the entrance roller pair are provided.

Abstract: An image forming apparatus including a plural number of paper transporting units including at least first and second paper transporting units, in-unit paper sensing mechanism located in the first paper transporting unit, unit-to-unit paper sensing mechanism located between the first and second paper transporting units, and drive control mechanism for controlling the operations of the plural number of the paper transporting units, wherein the drive control mechanism includes first mechanism operating such that when any of the in-unit paper sensing mechanism located in the first paper transporting unit detects a paper transport trouble, the first mechanism stops the paper transporting operation of the second paper transporting unit in response to a sensing signal indicative of the presence of a paper from the unit-to-unit paper sensing mechanism, and second mechanism stops the paper transporting operation of the first paper transporting unit upon the stop of the paper transporting operation of the second paper

Abstract: An apparatus for detecting the feeding of piled sheets along a sheet feeding path. The apparatus includes a first reflection plate of high reflectivity and a second reflection plate of low reflectivity. Means are provided for irradiating each of the plates with radiant rays. Means are provided for detecting the quantity of radiant rays reflected from each of the plates. Means are coupled to the detecting means for generating a signal indicating piled sheets being fed when the difference between the quantity of reflective rays from the first plate and the quantity of reflective rays from the second plate are below a predetermined level.