Windmoller Holscher

Windmoeller & Hoelscher Kg

Ludger Ottenhues

Gunter Rogge

Willi Meyer

Fritz Achelpohl

Lutz Telljohann

Heinz Wesselmann

A doctor blade device of a rinsable ink application device of a rotary press is cleaned by first pumping ink back out of an ink chamber of the doctor blade device via a discharge line into an ink tank. Subsequently, from a solvent tank and via a feed line, solvent is directed into the ink chamber. During a predetermined time span, solvent is directed via the discharge line into the ink tank. Subsequently, the solvent, which is still contaminated with ink, is pumped into a contaminant chamber within a predetermined time span. The solvent flow from the solvent tank is interrupted and the solvent is pumped into the contaminant tank. Fresh solvent is then pumped via the feed line into the ink chamber, the suction line to the solvent tank is closed, and the solvent is pumped via the feed and discharge lines within a closed rinsing cycle for a predetermined amount of time. The circulating solvent is then directed into the contaminant tank.

Process for cleaning a doctor blade device for a rinsable color inking

A doctor blade unit for the inking system of a rotary printing press consists of a doctor blade carrier, on which two doctor blades that can be brought into contact with an inking roller or screen roller are fastened parallel to one another in the approximate shape of a roof, with said doctor blades limiting an ink chamber in cooperation with the inking roller, the doctor blade carrier and sealing elements provided on the ends of said doctor blade carrier. Ducts for supplying and discharging ink into/out of the ink chamber and contacting units for pressing the doctor blade carrier against the inking roller are also provided. In order to ensure that both doctor blades can be pressed against the screen roller with exactly the same contact pressure, the doctor blade carrier is connected to a doctor blade unit carrier that is provided with the coupling rods of parallel pitman systems. The parallel pitmans are coupled to inking system flames or supports of the inking system flames.

Doctor blade unit for the inking system of a rotary printing press

A flexographic printing press comprising a plurality of inking units and plate cylinders and at least one impression cylinder, which is driven by a coaxial central gear in mesh with the gears of the plate cylinders rotatably mounted on plate cylinder carriages, which are adapted to move toward and away from the impression cylinder on tracks provided in the machine frame. That printing press is characterized in that each plate cylinder gear has a projection or hub provided on its periphery with angularly spaced detent bores equal in number to the plate cylinders and disposed on respective axially spaced peripheral lines. The plate cylinder carriages have detent pins, which are axially or angularly movable and are disposed in respective radial planes and are offset relative to each other so that each pin is adapted to enter that detent bore of that plate cylinder, which has a detent bore at a corresponding axial location. The detent bore of each plate cylinder has such an angular position that when the plate cylinders have been located on the plate cylinder carriages by means of the detent bores and the detent pins and the central gear has been adjusted to the proper angular position, the plates on the plate cylinders will be adjusted for printing in perfect register when the plate cylinders are caused to mesh with the central gear.

Flexographic printing press comprising a plurality of inking units and

In a doctor device comprising a doctor blade which is applicable to a plate cylinder of a printing press and is located in a doctor holder, the holder is pivotally connected to a beam parallel thereto by at least one leaf spring. A plurality of piston-cylinder units disposed on the beam in a row have their piston rods applied directly or indirectly by way of pressure bolts to the holder or a part connected thereto. The piston-cylinder units are fed by a pressure medium at an adjustable basic pressure. Each piston-cylinder unit is associated with a separately adjustable fine regulating valve by way of which an additional pressure can be superimposed on the basic pressure by introducing additional pressure medium.

Doctor device

In an intaglio printing press, apparatus for applying and withdrawing a pressure cylinder to the plate cylinder during replacement of the latter comprises displaceable journals for the pressure cylinder operatively connected to a piston-cylinder unit. To control the withdrawing motion of the pressure cylinder, a pressure medium is fed beneath the piston by way of a pressure regulating valve which is open during printing and which is moved to a closed position by a cam carried along by the piston rod.

Apparatus for applying and withdrawing a pressure cylinder acting on the

In an intaglio printing press where the impression cylinder is provided with two journals for mounting it in the frame of the press, the journals being operatively connected to respective screw-threaded spindles which are adjustable in unison or independently, apparatus for applying and withdrawing the impression cylinder to and from the plate cylinder comprises first and second rotatable nuts mounted on each spindle, the two nuts on each spindle being coupled for co-rotation. A hand wheel is operatively connected to said first nut to apply same to a respective abutment surface that is fixed with respect to the frame. A piston-cylinder unit is operatively connected to each said second nut to lift and lower same, the psiton-cylinder unit being supplied with pressure medium through independent fine control valves.

Apparatus for applying and withdrawing an impression cylinder acting on

In a multi-color rotary printing press equipped with a plate cylinder at each of a plurality of printing stations where a web is to be printed, the rotary positions of the plate cylinders are pre-adjusted to achieve registry of the printing applied at each printing station by setting all the plate cylinders to a respective zero rotary reference position relatively to a frame of the press and then turning each of the second and subsequent plate cylinders out of their zero positions through a respective angle subtended by an arc length calculated by dividing the web length between the first printing station and that at which adjustment is being effected by the circumference of the plate cylinder and subtracting from this quotient the nearest whole number below the quotient. A gauge is provided to facilitate pre-adjustment of the plate cylinders, the gauge being provided with a dial, showing the required adjustment values for the second and subsequent plate cylinders, and a pointer for indicating on a scale the instantaneous value through which the plate cylinder has been turned.

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Tecklenburg, Germany

Ludger Ottenhues