Xerox Corporation

Richard T Ziehm

Stephen P Wilczek

Raymond R Husted

Anthony M Federico

Keith G Bunker

George E Baker

Glen A Dumas

John A Adamek

George H Place, Jr

Curtis B Downing

Michael E Edmunds

The present invention is a multiprocessor machine control system in which the failure of one of the processors to reset can be ignored by the rest of the control system. In particular, a software crash or other abnormality on one of the processors will generate a reset procedure. If the processor cannot be reset, this will indicate a processor board failure such as a hardware failure. If the processor and its controlled elements are not crucial to the machine operation, then the control wll ignore the failed processor as though it were not in the control system, and continue with machine operation.

Remote processor crash recovery

An automatic document handling system 20 for recirculative precollation copying in reverse serial order of a set of simplex document sheets on a simplex and duplex copier 10 to provide precollated simplex or duplex (two-sided) copies with proper orientation of the document images on the outputted copy sheets 128 for copies made on preprinted, prepunched, or other special orientation restricted copy sheets, as well as for copies made on plain paper or other non-orientation sensitive copy sheets. The copier 10 has a special copy sheet supply 107 for said special orientation restricted copy sheets and a main copy sheet supply 106 restricted to conventional nonorientation sensitive copy sheets. Switching systems, e.g. 200, provide for selecting between the feeding of copy sheets from the main supply 106 or the special copy sheet supply 107 and for selecting between simplex or duplex copying, and connect with overall control system 100. The control system 100 causes the document handling system 20 to circulate the set of document sheets once before copying them, to count them and determine whether there are an odd or even number, only in response to both the first switching system 200 selection of the special copy sheet supply 107 rather than the main copy sheet supply 106 and the selection of duplex copying rather than simplex copying. The former selection is automatically removed after each copying run. If copies are made from the main tray 106 copying begins on the first circulation of the documents. Thus this system improves the efficiency of systems such as that of U.S. Pat. Nos. 4,330,197 and 4,278,344.

Recirculative document duplex copying

The present invention is a multiprocessor control system that allows full job recovery after a machine power down or after a malfunction or software crash or temporary power outage. In particular, essential variables such as the state and status of the machine and the programmed job at the time of the malfunction are maintained in nonvolatile memory. This information is continually updated in nonvolatile memory. Once the control system has reset and reinitialized all the control elements after a malfunction, the control restores or downloads all the relevant variables in the nonvolatile memory to the various control elements to maintain status. In another embodiment, the essential variables are maintained in RAM locations in a master processor and saved for downloading to the control elements.

Control system job recovery after a malfunction

A method and apparatus for clearing jams in the transport path of a copier includes the steps of sensing a jam, clustering in-process sheets either at the jam location or at an area upstream of the jam location while simultaneously allowing sheets downstream from the jam location to continue out into a catch tray and removing the jam sheets after the last downstream sheet has exited the copier and the machine has stopped.

Method and apparatus for clearing jams in copiers

A method and apparatus for providing duplex copies in pre-collated output copy sets from a set of documents recirculated in order by first copying only the even-ordered documents in the set once onto the first sides of substrates and transporting those copies to a buffer; then making individual copies in order of all the documents by alternately copying odd order documents on the reverse side of copies fed from the buffer while alternately copying even ordered documents onto copy substrates fed from a different copy substrate source, and transporting the copies made from the buffer to an output tray to create pre-collated sets while simultaneously transporting the copies from the other copy substrate source to the buffer to replace the copies fed therefrom; repeatedly individually copying all of the documents in the set in the latter manner by a number of document recirculations equal to one less than the total number of copy sets desired, and then, for a last copy set, making copies of only the odd ordered documents onto the reverse side of copies fed only from the buffer.

Growing community of inventors

Webster, NY, United States of America

Richard T Ziehm