Method and apparatus for automatic "two-up" copying with intermediate latent image copiers

In a copying apparatus wherein an undeveloped electrostatic latent image may be formed from an original document sheet imaged on a platen of said copying apparatus and retained on an intermediate latent image retention member of said copying apparatus before being developed and transferred to a copy sheet, the improvement comprising:

• document handling means for individually sequentially feeding and individually copying plural original document sheets in a preselected page order on said copying apparatus platen;
• means for forming and retaining at least two closely adjacent (side-by-side) plural undeveloped latent images on said image retention member from at least to said sequentially fed documents;
• means for directly sequentially developing and directly sequentially transferring said plural developed intermediate images onto one side of a single copy sheet;
• wherein said intermediate latent image retention member comprises an intermediate member, separate from said means for developing and trasferring, with means for transferring said plural latent images thereto;
• and means for repeating the above steps to form ordered sets of copy sheets with plural adjacent images on each copy sheet.

In a copying apparatus wherein electrostatic intermediate latent images may be formed from document sheets and temporarily retained on an electrostatic image retention member, developed, and the developed image transferred to a copy sheet, the improvement comprising:

• document handling means for receiving and automatically reordering a set of document sheets from their normal order into signature page order and for sequentially individually feeding plural original document sheets in a signature page order for individual sequential copying on said copying apparatus;
• means for sequentially forming two closely circumferentially adjacent latent images on said electrostatic image retention member from two said sequentially copied documents so reordered in said signature page order;
• means for developing and transferring both said circumferentially adjacent sequential images onto one side of a copy sheet fed to said image retention member;
• means for inverting and representing the copy sheet to said image retention member for receiving two or more images from two more said documents on the opposite sides thereof;
• and means for repeating the above steps to form sets of signature copy sheets.

In a copying apparatus wherein at least one undeveloped electrostatic intermediate latent image may be formed from document sheets imaged on a platen and temporarily retained on a rotatable electrostatic latent image retention member, said member having a circumferential length greater than said latent image thereon, before being developed and the developed images transferred to copy sheet, including document handling means for sequentially feeding and exchanging plural original document sheets for sequentially copying them on said platen of said copying apparatus one at a time at the same position;

• further including:
• means for forming and temporarily retaining at least one said undeveloped latent image from one said document on said latent image retention member;
• means for sequentially forming a second latent image, from a second sequentially copied document, on said same latent image retention member circumferentially closely adjacent said first latent image, said means including means for rotating latent image retention member between said forming of said first and second latent images;
• and
• means for developing and transferring both said circumferentially adjacent first and second sequential images onto one side of a copy sheet fed to said same latent image retention member.

In a copying method wherein electrostatic intermediate latent images may be imaged from document sheets, and temporarily retained on an image retention member, developed, and the developed image transferred to a copy sheet, the improvement comprising the steps of:

• individually sequentially feeding and individually sequentially copying and exchanging said document sheets;
• forming circumferentially closely adjacent latent images on said image retention member from two or more of said copied documents by intermediately rotating said image retention member between said imaging of said documents and while said documents are being exchanged;
• developing and transferring said adjacent images to one side of a single copy sheet fed to said image retention member;
• and repeating the above steps.

In a copying method wherein at least one undeveloped electrostatic intermediate latent image may be formed from document sheets imaged on a platen and temporarily retained on a rotatable electrostatic latent image retention member, said member having a circumferential length greater than said latent image thereon, before being developed and the developed images transferred to copy sheet, including sequentially feeding and exchanging plural original document sheets for sequentially copying them on said platen of said copying apparatus one at a time at the same position;

• further including the steps of:
• forming and temporarily retaining at least one said undeveloped latent image from one said document on said latent image retention member at an exposure position;
• sequentially forming a second latent image, from a second said sequentially copied document, on said same latent image retention member at said exposure position circumferentially closely adjacent said first latent image, including continuing said rotating of latent image retention member between said forming of said first and second latent images until the trail edge area of said first undeveloped latent image has just passed said exposure position again before starting said forming of said second latent image;
• and
• developing and transferring both said circumferentially adjacent first and second sequential images onto one side of a copy sheet fed to said same latent image retention member.