Donald J Schaeffer

US Patent:

44681143, Aug 28, 1984

Filed:

Dec 10, 1982

Appl. No.:

6/448655

Inventors:

Susan J. Pels - Rochester NY
Donald W. Schaeffer - Webster NY

Assignee:

Xerox Corporation - Stamford CT

International Classification:

G03G 1500

US Classification:

355 14R

Abstract:

In recirculatively precollatively copying a set of plural original documents onto both sides of copy sheets to produce a desired plural number precollated duplex copy sheet sets, by normally copying the documents only once in each copying circulation of the document set onto one side of copy sheets to form a duplexing buffer and copying other documents onto the opposite sides of the buffer copies to form duplex precollated copies, the improvement comprising: counting the number of documents in the document set and determining that the number of documents is only two or three, and in response to the determination, automatically switching the mode of copying of the documents to a higher productivity two or three document set mode in which plural identical consecutive copies are first made from only one document (the first document page) by halting the first copying circulation of the document set to copy only the one document, and forming the buffer from these plural identical copies and then skipping the copying of the same one document in the subsequent production of a number of copy sheet sets corresponding to the number of the plural identical copies. If the determined number of documents is two, the number of plural identical copies made is equal to the number of copy sets made, but not more than 14, and the document set is circulated not more than three times for up to 14 copy sets. If the determined number of documents is three, the plural number of identical plural copies made is four, and all documents other than the first document copies are copied only once in each document set circulation.

US Patent:

47454385, May 17, 1988

Filed:

Sep 16, 1986

Appl. No.:

6/908052

Inventors:

Thomas Acquaviva - Penfield NY
Donald W. Schaeffer - Webster NY

Assignee:

Xerox Corporation - Stamford CT

International Classification:

G03G 2100

US Classification:

355 14SH

Abstract:

A fade-out system for a copier with a document feeder, for preventing the undesired development of areas of the photosensitive imaging surface relative to the desired latent images of the document with a variable magnification optical imaging system, preventing "show around" copy defects from the document feeder, where the document feeder transports the document sheets in a document path onto and over the copying platen of the copier. An array of plural document sensors is positioned in the document feeder for measuring both the length and width of the document sheets being transported onto the copying platen, and the fade-out system connects with and is controlled by both the array of plural document sensors and the magnification setting of the optical imaging system for preventing development of any areas of the photosensitive imaging surface outside of the latent images of the documents irrespective of the size of the document sheets or the magnification setting. The array of sensors is adjacent the platen and in the document path from both of the document sheet inputs to the platen. The fade-out system is further responsive to the actual size of the copy sheets on which copies are being made, for automatic flood illumination of areas of the photosensitive imaging surface outside of the smaller of the two of the document latent image area or the actual copy sheet size, by fading out any portions of the document latent image area which will not be engaged for image transfer by the copy sheet, and fading out otherwise developable nondocument latent image areas of the photosensitive imaging surface even if they are within areas of the photosensitive imaging surface which will be engaged by the copy sheets, so as to provide complete fade-out for any selected magnification or document size or copy size.