Didde-glaser, Inc.

Didde Graphic Systems Corporation

Terry N Faddis

Howard L Propheter

Kenneth C Clifton

Thomas D Parks

Robert A Sweet

Glen H Ensminger

An offset printing press is provided with a novel dual form planetary inker having improved printing characteristics. In use, a plate cylinder rotates to initially contact an ink/water form roller and subsequently contact a second form roller which is devoted exclusively to ink. The ink form roller is operable to insure that voids caused by lint, dust and other debris in the ink train are covered by the second form roller; additionally, the ink form roller provides a second working nip through which a second layer of ink is averaged with the previously deposited ink layer, such that ghosting is substantially eliminated. Both of the form rollers as well as numerous distributor rollers are rotatably carried by a shiftable frame which is pivotally interconnected with a support that carries the plate cylinder. The frame is shiftable from a first position wherein the forms are in rolling engagement with the plate cylinder and a second position wherein both of the forms are spaced from the plate cylinder; however, as the frame is lowered toward its first or working position, the ink/water form is disposed to contact the plate cylinder before the ink form, such that the plate is effectively dampened before ink is applied thereto. In particularly preferred forms, the planetary inker engages the plate cylinder on only two lines of contact, such that any one of a number of various plate cylinder diameters may be utilized.

Dual form planetary inker

A low cost, variable, modular, web-fed offset lithographic printing unit or tower is disclosed which allows significant economies in production and maintenance, and can be easily and quickly modified in the field using interchangeable modules so as to vary printing characteristics. The printing tower, in the straight-through variable perfector form thereof, is preferably provided with a printer module having upper and lower web-printing blanket rollers; in addition, the tower has corresponding upper and lower inker modules for the respective blanket rollers. The upper inker module is mounted for pivotal movement about a horizontal axis so that it can be shifted between a normal inking position over the printer module to a retracted, printer module-clearing position allowing removal and/or replacement of the printer module by essentially vertical shifting of the printer module. By virtue of modular construction, the supporting sidewalls for the separate tower modules can be of varying thicknesses sufficient for support of the intended module components, and thus the necessity of uniformly thick, expensive tower sidewalls, and the manufacturing problems associated therewith, is completely avoided. In addition, the modular tower permits mass production of certain universally used modules to lower costs, and also allows the user to stock extra and/or different tower modules to facilitate field repair or alteration of the tower.

Modular offset lithographic printing tower

A planetary inker for an offset printing press which uses only a single ink form roller but is substantially ghost free. A unique arrangement of distributor rollers operably associated with the form roller are present in sufficient number and of relative diameters with respect to each other and to the form roller to assure complete smoothing out of ink supplied to the form roller in conjunction with total elimination of all plate-derived latent images on the surface of the form roller before recontacting the plate on the plate cylinder. Especially efficient transfer of ink from the supply fountain to a drum roller in rolling contact with the form roller ahead of the distributor rollers is obtained in a preferred embodiment by the use of a pair of ink transfer ductors which are alternately intermittently shifted into engagement with the fountain ink ball and then the form roller vibrator. The relative time of engagement of the ductors with the ball and the vibrator may be selectively varied by the operator.

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Emporia, KS, United States of America

Terry N Faddis