Compatible copying of computer form documents

A document feeding apparatus for automatically feeding either individual sheet documents or computer form web documents to the imaging station of a copier for copying comprising:

• common feeding means for automatically feeding either of said two types of documents to the imaging station,
• sensing means for automatically determining which of the two types of document is being fed by said common feeding means,
• and dual mode feeding and registration means controlled by said sensing means, having a first mode for individually feeding and registering individual document sheets automatically, and a second mode for incrementally feeding and registering incremental length segments of a computer forms web automatically.
• said dual mode feeding and registration means automatically switching from said first mode to said second mode in response to said determination that the type of document being fed is a computer forms web,
• wherein said common feeding means for feeding both types of documents comprises a frictional feed wheel rotated over the platen and plural document nip exit rollers downstream of the platen, both commonly driven for different time periods in said first and second modes of operation,
• and wherein said frictional feed wheel is automatically lifted and optically shuttered to prevent its exposure during the copying of a document.

A method for automatically rapidly feeding document pages in a document path into registration over the platen of a copier wherein the document pages comprise either individual sheet documents or plural connected segments of an elongate computer forms web document, comprising the steps of:

• initially commonly frictionally feeding either an individual sheet or the first said segment of a computer forms web automatically over the platen and accurately registering the leading edge of either over the platen in an individual sheet document mode with controlled slippage of said feeding against a mechanical registration gate automatically placed in the document path adjacent the downstream end of the platen regardless of whether the document is an individual sheet or the first segment of an elongate computer forms web;
• automatically sensing that an elongate computer forms web document was so fed to the platen by sensing that the document length exceeds a preset length and also by sensing that said same document has sprocket holes;
• and then automatically switching from said individual sheet document mode to a computer forms web document mode for feeding and registering of subsequent segments of a computer forms web in response to said sensing of an elongate computer forms web document with sprocket holes, or remaining in said individual sheet document mode if an elongate computer forms web document is not so sensed,
• wherein in said computer forms web document mode subsequent computer forms web segments feedings and registrations are accomplished by automatically incrementing the web over the platen in preset incremental feeding distances controlled by sensing and counting sprocket holes in the computer forms web and without utilizing said mechanical registration gate;
• and wherein in said individual sheet document mode individual sheet registrations are accomplished by automatically appropriately cycling said mechanical registration gate in and out of the document path;
• so that the leading edge of a computer forms web and all individual sheet documents are driven and registered against said mechanical registration gate over said platen.

Document feeding means for automatically feeding document pages in a document path into registration over the conventional platen of a copier, wherein the document pages comprise either individual sheet documents or plural connected (unseparated) segments of an elongate computer forms web document, comprising:

• feeding means for initially commonly rapidly feeding either an individual sheet or the first segment of a computer forms web automatically over the platen and accurately registering the leading edge of either over the platen in an individual sheet document mode with controlled slippage of said feeding means against a mechanical registration gate automatically placed in the document path adjacent the downstream end of the platen regardless of whether the document is an individual sheet or the first segment of an elongate computer forms web;
• means for automatically sensing that an elongate computer forms web document was so fed to the platen by sensing that the document length exceeds a preset length and by also sensing that said same document has sprocket holes;
• and means for automatically switching from said individual sheet document mode to an elongate computer forms web document mode for the feeding and registering of subsequent segments of the computer forms web only in response to said sensing of an elongate computer forms web document with sprocket holes,
• wherein in said computer forms web document mode subsequent computer forms web segment feedings and registrations are accomplished by automatically incrementing the web with said feeding means in preset incremental feeding distances controlled by sensing and counting sprocket holes in the web and by means for maintaining said mechanical registration gate out of the document path;
• and wherein in said individual sheet document mode individual sheet registrations are accomplished by means for appropriately automatically cycling said mechanical registration gate in and out of the document path and by feeding each individual sheet document against said registration gate with said feeding means while said registration gate is in said document path;
• so that the leading edge of a computer forms web and all individual sheet documents, are driven and registered against said mechanical registration gate over said platen.

In a document handling apparatus for a copier having a platen for supporting and copying a document at the imaging station of the copier, and a platen cover unit with a uniform imaging background surface overlying the platen, and frictional document feeding means in said platen cover unit for feeding a wide range of documents across said platen by frictional engagement therewith, said frictional document feeding means overlying said platen and extending through at least one aperture in said imaging background surface, the improvement comprising:

• means for automatically detecting that the document to be fed by said document feeding means has both edge apertures of a defined pattern and a length exceeding a preset length, and automatically changing the operation of said document feeding means to an aperture count controlled incremental feeding computer form web mode of operation in response to detecting both;
• automatic lifting means for automatically lifting said document feeding means into said platen cover unit through said aperture prior to copying a document on said platen;
• and automatic shuttering means for automatically covering said aperture with an optically uniform shutter optically integral said uniform imaging background surface, after said automatic lifting means have lifted said document feeding means, to prevent copying of said aperture or said document feeding means, and then automatically opening said aperture after copying of a document on said platen;
• said automatic lifting means, after said opening of said shutter, automatically lowering said document feeding means into feeding engagement with the document on the platen after the copying of the document.