1. Field of the Invention
The present invention relates to a device for repetitively copying originals in a copier. The device includes a pivotable separating guide which is moved to different positions for the separate discharge of, respectively, comparatively small format originals and comparatively large format originals.
2. Discussion of Related Art
A device of the above type is described in German Pat. No. 2,657,198 and in U.S. Pat. No. 4,269,409, in which the front edge of a copying original is guided through a plurality of revolutions past a copying station for repetitive copying by a gripping unit which moves along a closed path. In this copier, two vertically spaced discard-tables are provided beneath the repetitive copying device. The upper discard-table receives the comparatively small format originals, while the lower discard-table receives the comparatively large format originals. During repetitive copying, if the originals are large, for example DIN A 0 and A 1, the separating guide is pivoted away and an air nozzle, situated beneath the repetitive-copying device, is turned on. This nozzle applies blown air to the rear surface of the copying original. At the same time, a loop is formed by the copying original. This loop is not supported but, on the contrary, hangs freely downward. As this occurs, the stream of air is intended to distend the loop, in an appropriate manner, in order to eliminate excessively small radii in the loop, which can easily lead to sharp bends in the copying original.
With this arrangement, it has been found that the stream of air from the air nozzles yields results which are, as a rule, satisfactory for a certain type or quality of paper. However, when the paper quality deviates therefrom with regard to the stiffness, or when sharp bends, creases, hanging-strips or the like are present in the copying original, it is impossible to form a defined loop with a constant radius over its width. As a result, sharp bends occur in the copying original and, if the repetitive copying process is carried out on more than one occasion, these sharp bends are capable, after further repetitive-copying operations, of causing cracks and thereby rendering the copying original unusable. This is especially true in the case of brittle materials which are used, for example, if the operation involves the copying of old transparencies. Also, with this known device, large-format originals, such as DIN A 0 and A 1, can be damaged after leaving the transport rollers of the repetitive device, by falling down onto the discard-table.
USPTO Backgrounds
USPTO Backgrounds