Abstract: In a process for producing a stipulated intensity distribution of a working laser beam on an object surface, at least one first and one second component beam with a stipulated first and second intensity distribution are formed and the power of each component beam is changed in a controlled manner with switching times down to submicroseconds. The component beams at a third intensity distribution superimposed as the working beam are pointed at or into the object in order to achieve a different action as a result of a varied third intensity distribution of the working beam. In contrast to conventional processes the first intensity distribution Ib=a×fb(x, y, t) differs from the following one In=a×fn(x, y, t) by the value of the function fu(x, y, t) and no longer only by an altered linear value a. The process as claimed in the invention can be preferably used in the production of screen cells on an engraved cylinder.

Abstract: A doctor blade for wiping excess printing ink off the surface of a printing form (10) has a front section in the form of a leaf (3) which interacts with the surface of the printing form (10). In order to avoid wear or damage to the printing form surface as a result of the contact pressure exerted by the leaf (3) on the printing form surface, the leaf (3) is provided with a coating (5) over the entire doctor blade length. The coating (5) consists of lubricant or contains lubricant particles (8). As a result of the significant reduction in friction between the leaf (3) and the printing form surface, not only is the wear on the printing form surface reduced, but the wear on the doctor blade is also reduced, and its service life is extended.

Abstract: In an engraving head for apparatus for engraving printing cylinders, a drivable engraving tool and a sensing organ contacting any printing cylinder being engraved by the drivable engraving tool are mounted on a common fixture. A damping element is located between the sensing organ and the engraving tool for at least substantially barring transmission of oscillations from the sensing organ to the engraving stylus, while preserving a firm and accurate guidance of the drivable engraving tool by the sensing organ contacting the printing cylinder. Damped sleeve structures and collets for mounting a sensing stylus include such damping elements.

Abstract: During electrolytical treatment, a printing cylinder is held between center points, of which one is provided adjustably with a centering sleeve in a tail spindle. A belt connects the tail spindle in force transmitting relationship to a drive. The tail spindle is axially displaceable together with the inner housing of the apparatus, so that an electric contact ring at the end of the tail spindle is engageable with the front surface of a printing cylinder. The current conduction to the contact ring takes place via cooled carbon brushes located between the tail spindle bearings and the contact ring. A current conducting sleeve encompassing the end region of the tail spindle and being contacted by the carbon brushes, prevents the tail spindle carrying the printing cylinder from being exposed to electric current.

Abstract: A flexible wrap-on printing plate structure has a flexible printing plate body extending between opposite first and second edges at which the printing plate structure is attached to a rotary printing form cylinder. A thickening of the printing plate body or other means extend along a third edge of the printing plate body between the mentioned first and second edges for mechanically stiffening the printing plate body along that third edge, so that no warping of the printing plate structure and no printout of printing plate margins can occur.

Abstract: A wrap-on printing plate with first and second clamping bars along opposite sides thereof for installation on a printing cylinder is produced by providing a layer defining a printing plate body, forming from marginal portions of that layer, along opposite sides thereof, first and second foundations for the first and second clamping bars, respectively. These clamping bars are provided on such first and second foundations by interatomic bonding between the first and second foundations and the first and second clamping bars, respectively. To this end, the layer may, for instance, be electroplated on existing clamping bars in a special form, or, as presently preferred, material from which the first and second clamping bars are formed may be electroplated on the first and second foundations formed in marginal portions of the mentioned layer.

Abstract: A doctor or doctor blade is embedded in an enclosure or casing formed of plastic. The portion of such enclosure covering the region of a work edge of the doctor blade is connected with the remaining part of the enclosure by means of a reference fracture location in the form of notch-shaped weakening lines. These weakening lines determine the separation location between both of the enclosure sections or portions. After mounting the doctor blade, protected by the enclosure or casing, the work edge is exposed by separating the enclosure portion or section covering the work edge, whereas the remaining part of the enclosure remains at the doctor blade.

Abstract: A form cylinder for rotary intaglio printing presses comprises first and second half cylindrical parts which are joined together to form a cylinder having diametrically opposite recesses and with each part having a facing side facing the respective other cylinder part with a clamping device recess defined therein. At least one flexible printing plate extends over each cylindrical part and is connected at each end to a profile piece in the form of an angle member which is displaceably positioned in each respective recess. A clamping mechanism in the form of a toggle is provided in the recess of the cylindrical part and it includes a drive member for actuating the toggle to displace the profiled member to effect tensioning of each printing plate both in tangential and radial directions.