US3577856A — Apparatus for offset printing

Claim 1

Independent Claim 133 words

In an offset printing system in which images carried on straightedge plates are reproduced on paper with ink in an offset printing press, an improved apparatus for preparing the straightedge plates comprising a light table unit having a light surface, a plurality of guidelines formed on said light surface, said guidelines including horizontal lines corresponding to the lead and tail edges of the maximum size image capable of being printed on the offset press with vertical and horizontal scales and three flat stops mounted on and projecting upwardly from said light surface in fixed position relative to said guidelines, said flat stops being oriented with respect to one another and to said guidelines to provide a three-point reference for positioning a sheet of light-blocking material over said guidelines in the production of flats.

Claim 2

Dependent Claim 133 words

In an offset printing system in which images carried on straightedge plates are reproduced on paper with ink in an offset printing press, an improved apparatus for preparing the straightedge plates comprising a light table unit having a light surface, a plurality of guidelines formed on said light surface, said guidelines including horizontal lines corresponding to the lead and tail edges of the maximum size image capable of being printed on the offset press with vertical and horizontal scales and three flat stops mounted on and projecting upwardly from said light surface in fixed position relative to said guidelines, said flat stops being oriented with respect to one another and to said guidelines to provide a three-point reference for positioning a sheet of light-blocking material over said guidelines in the production of flats.

Claim 3

Dependent Claim 49 words

The apparatus for preparing straightedge plates as defined in claim 1 wherein said guidelines further include a pair of vertical lines cooperating with said horizontal lines to define an area corresponding to the maximum image area of the press, and said flat stops are positioned outboard of said area.

Claim 4

Dependent Claim 109 words

The apparatus for preparing straightedge plates as defined in claim 8 further comprising a support including an assembly surface having three plate guides mounted thereon in fixed spaced relation to one another and cooperating to provide a three-point reference for accurately positioning a straightedge plate thereon, three flat guides mounted on said assembly surface in spaced relation to one another and tO said plate guides, said flat guides providing a three-point reference for accurately positioning a flat in superimposed relation on a plate which has been positioned by said plate guides, and clamp means for releasably retaining a flat in superimposed relation on a plate on said assembly surface.

Claim 5

Dependent Claim 37 words

The apparatus for preparing straightedge plates as defined in claim 3 further comprising means independent of said clamp means for releasably retaining a straight edge plate on said assembly surface in position defined by said plate guides.

Claim 6

Dependent Claim 59 words

The apparatus for preparing straightedge plates as defined in claim 4 wherein said plate guides are movable between a projected position extending above said support surface providing a three-point reference for positioning a straightedge plate and a retracted position beneath said assembly surface, and selectively operable means for moving said plate guides between said projected and said retracted position.

Claim 7

Dependent Claim 67 words

The apparatus for preparing straightedge plates as defined in claim 4 wherein said means independent of said clamp means for releasably retaining a straightedge plate on said assembly surface comprises a plurality of openings in said support surface, and vacuum means mounted on said support in position to induce a flow of air through said support in a direction tending to retain said plate on said surface.

Claim 8

Dependent Claim 23 words

The apparatus for preparing straightedge plates as defined in claim 3 wherein said flat guides are adjustable with respect to said plate guides.

Claim 9

Dependent Claim 31 words

The apparatus for preparing straightedge plates as defined in claim 3 wherein the position of said flat guides correspond to the position of said flat stops on said light table unit.

Claim 10

Dependent Claim 51 words

The apparatus for preparing straight edge plates as defined in claim 8 wherein the positions of said plate guides on said assembly surface correspond with the positions of three plate guides on the plate cylinder or plate segment of an offset printing press with which the apparatus is to be used.

Claim 11

Dependent Claim 170 words

In an offset printing press having a plate segment wheel, a plate segment, means mounting said plate segment on said wheel, and lead and tail edge plate clamps mounted on said plate segment for releasably clamping the lead and tail edges respectively of a straightedge plate on said plate segment, the improvement comprising, a pair of fixed axially spaced and substantially aligned lead edge guides mounted on said plate segment and projecting radially outwardly therefrom beneath said lead edge plate clamp, and a fixed side guide mounted on said plate segment and projecting radially outwardly therefrom adjacent one end of said lead edge plate clamp and circumferentially offset from said lead edge guides, said side guide being positioned to engage one side edge of a straightedge plate when the plate is installed on said plate segment with the lead edge in engagement with said lead edge guides, said lead edge and said guides cooperating to provide a fixed three-point reference for accurately positioning a straightedge plate on said plate segment.

Claim 12

Dependent Claim 170 words

In an offset printing press having a plate segment wheel, a plate segment, means mounting said plate segment on said wheel, and lead and tail edge plate clamps mounted on said plate segment for releasably clamping the lead and tail edges respectively of a straightedge plate on said plate segment, the improvement comprising, a pair of fixed axially spaced and substantially aligned lead edge guides mounted on said plate segment and projecting radially outwardly therefrom beneath said lead edge plate clamp, and a fixed side guide mounted on said plate segment and projecting radially outwardly therefrom adjacent one end of said lead edge plate clamp and circumferentially offset from said lead edge guides, said side guide being positioned to engage one side edge of a straightedge plate when the plate is installed on said plate segment with the lead edge in engagement with said lead edge guides, said lead edge and said guides cooperating to provide a fixed three-point reference for accurately positioning a straightedge plate on said plate segment.

Claim 13

Dependent Claim 34 words

In an offset printing press as defined in claim 10, the further improvement comprising, guide means for accurately positioning said plate segment on said plate segment wheel in its maximum image size printing position.

Claim 14

Dependent Claim 76 words

The offset printing press as defined in claim 11, wherein said guide means comprises a tapered opening in said plate segment, a tapered opening in said plate segment wheel in axial and radial alignment with said tapered opening in said plate segment when said plate segment is installed in its maximum image size printing position, and removable taper pin means insertable into said tapered openings to accurately position said plate segment on said plate segment wheel.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1974-05-10	1974-11-09	1975-05-11	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1978-05-10	1978-11-09	1979-05-11	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1982-05-10	1982-11-09	1983-05-11	$7700.00	Window Closed / Lapsed

Apparatus for offset printing

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