An ink fountain for supplying ink to the ink carrying surface of a printing press form roll has an ink receptacle which may be removed from and reinstalled into the press separate from the adjustable support assembly which maintains it in an operative position with respect to the form roll. The adjustable support assembly enables a doctor blade on the ink receptacle to be placed in an optimum position with respect to the ink carrying surface of the form roll. Dam members which seal front portion...

A construction of ink dispensing roller is described in which a porous ink metering layer extends around a peripheral surface of a porous ink reservoir. To prevent relative movement between the ink metering layer and the ink reservoir, the ink metering layer is securely located relative to the ink reservoir by means of elements of the ink metering layer extending beyond each axial end of the ink reservoir and being clamped between end cheeks and the axial end walls of the ink reservoir. The ink ...

A dampening unit for an offset printing machine having a plate cylinder which carries a printing form and which is operatively connected to applicator rollers of an inking unit and of a dampening unit. To improve the print quality appreciably by means of uniform, fault-free feed of dampening medium to the plate cylinder, particularly during the processing of special inks having relatively high metallic pigment components, a dampening applicator roller receives a feed of dampening medium upstream...

Inking unit rolls include at least one ink applicator roll, which rotates in an ink fountain filled with printing ink and picks up printing ink from the latter, and a plate cylinder, which serves as a printing plate carrier and onto which ink can be transferred, directly or indirectly, by the ink applicator roll. The short inking unit is therefore equipped with a small number of inking unit rolls and, at the same time, nevertheless ensures a uniform, homogeneous application of ink to the plate c...

A transfer control roller having individually adjustable surface portions is provided between a fountain roller and a succeeding ductor roller. The surface portions can be moved radially inwardly and outwardly to vary the content surface between the fountain roller and respective surface portions, thereby varying the amount of transferred ink or water.

To control the amount of ink transferred between an ink application cylinder (2) and an ink supplying cylinder (1) having a cellular surface, such as an anilox roller or another roller or cylinder having ink receptor cells and/or a further cylinder (3) such as a plate cylinder, the ink application cylinder (2) is formed with a yieldingly compressible surface and the yieldingly compressible surface is pre-compressed by application of a surface compression roller (4) thereagainst. The surface comp...

An ink metering member (10') to form a thin film (130) of ink on a resilient roller surface (45) wherein the metering member comprises a hard, elongated strip having a first polished leading edge (25) and a second polished trailing edge (28b) formed on each side of a polished support surface (26) urged into pressure indented relationship with the resilient roller. The metering member further has a relieved area (27) formed in a lower surface (28) adjacent the lower trailing edge (28b) to prevent...

In a lithographic printing apparatus, the rollers that supply ink and/or water to form rollers have a surface with minutely intermixed hydrophilic and oleophilic areas. The amount of water retained by a roller is dependent upon the total of the hydrophilic areas, and the amount of oil-based ink retained by the roller is dependent upon the total of the oleophilic areas. A preselected ratio of oil to water is obtained by selecting the ratio of hydrophilic areas to oleophilic areas.

The dampening apparatus and method provides automatic ink/water control for a lithographic printing press by means of a hydrophylic metering roll in a pan for fountain solution which contacts an oleophylic transfer roll. The transfer and metering rolls are free wheeling friction driven rolls which are driven in substantially a one-to-one surface speed ratio by friction between the transfer roll and a dampener form roll to cause the metering roll to provide an unmetered excess of dampening fluid ...

An engraved ink transfer cylinder for a flexographic printing press, wherein the roller body (12) is clamped detachably on a continuous axle (22) and surrounds this axle (22) at a distance.