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US 4,579,444 AGranted
Document registration system
AssigneeXerox Corporation
InventorsTimothy S. Pinckney, Hector J. Sanchez
Life of this patent
Estimating the term…
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AssigneeXerox Corporation
InventorsTimothy S. Pinckney, Hector J. Sanchez
Estimating the term…
In a document feeder for a copier which transports a document sheet onto and over the platen of the copier and which places the document in a desired registration position on the platen for copying by stopping the document platen transport of the document feeder, and thereby stopping the document being fed thereby at the desired position, without the document hitting a mechanical registration stop, the improvement comprising a variable registration control system for controlling the document platen transport to stop at a desired calculated stopping position, including a sensor adjacent by a known fixed distance the upstream, entrance, side of the platen for sensing the trail edge of an individual document sheet being transported onto the platen by the document platen transport, providing a first signal indicative of the selected size of the copy sheet onto which that document sheet is to be copied, providing a second signal indicative of the optical magnification or reduction ratio with which that document is being copied onto that copy sheet, and wherein the variable registration control system calculates a particular registration stopping position on the platen for that document which is controlled by the trail edge sensor and the first and second signals to provide appropriate document registration for the selected copy sheet size and copying magnification or reduction ratio.
In a document feeder for a copier which transports a document sheet onto and over the platen of the copier and which places the document in a desired registration position on the platen for copying by stopping the document platen transport of the document feeder, and thereby stopping the document being fed thereby at said desired position, without the document hitting a mechanical registration stop, the improvement comprising:
In a method of copying in which a document feeder for a copier transports a document sheet onto and over the platen of the copier and the document sheet is automatically positioned in a desired registration position for copying onto a selected copy sheet by stopping the document feeder, and thereby stopping the document being fed thereby at said desired position, rather than by having the document hit a mechanical stop, the improvement in the step of stopping the document feeder comprising controlling the document feeder to stop the document at a desired calculated stopping position, wherein the calculation and control includes the steps of sensing the trail edge of the document at a known position as the document is being fed onto the platen by the document feeder, obtaining a first signal indicative of the selected size of the copy sheet onto which that document sheet is to be copied, obtaining a second signal indicative of the optical magnification or reduction ratio with which that document is being copied onto that copy sheet, and then calculating a particular registration stopping position on the platen for that document which is controlled by said trail edge sensing and said first and second signals to provide an appropriate document registration for the selected copy sheet size and copying magnification or reduction ratio.
Dependencies are inferred from the claim text.