# US 5,699,742 A · Method and device for exactly aligning a printing image relative to a geometrically correct print position of a printing machine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,699,742 A - Document ID: US5699742A - Status: Granted - Kind: A - Application number: 08/664,719 - Filed: 1996-06-17 - Granted: 1997-12-23 - Earliest claimed: 1995-06-22 - Assignees: Polygram International Holdings B.V. - Inventors: Harald Ahrens; Rainer Tiebel; Rainer Ziefle - Web page: https://patentgrep.com/patent/US5699742A ## CPC - B41F 27/005: {Attaching and registering printing formes to supports} - B41F 15/36: flat - B41P 2215/55: for printing compact discs - Y10S 101/36: Means for registering or alignment of print plates on print press structure - B41F: PRINTING MACHINES OR PRESSES (manifolding devices or office printing machines B41L) - B41P: INDEXING SCHEME RELATING TO PRINTING, LINING MACHINES, TYPEWRITERS, AND TO STAMPS - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS ## Abstract A method and a device exactly aligning a printing image relative to a geometrically correct print position of a printing machine for printing carriers, for example CDs, which employ use of a printing foil having a hole system which has been aligned relative to the image center and being secured to a printing screen having locating bores which have been aligned relative to the image center and which correspond to locating pins of the printing machine which have been aligned relative to the carrier center. In accordance with the method, (a) the printing foil is provided with at least two registration marks which have been aligned relative to the image center and is secured to the printing screen in a substantially centered relationship, (b) the printing screen is movably secured to an optical centering device comprising master pins which are positionally identical to the locating pins of the printing machine, (c) the registration marks of the printing foil are brought in register with positionally identical registration marks of the optical centering device, (d) centering elements are slid onto the master pins with an accurate fit, and (e) the master pins provided with the centering elements are made to engage the radially enlarged locating bores of the printing screen with clearance and are secured in their centered positions. ## Claims ### Claim 1 A method of exactly aligning a printing image relative to a geometrically correct print position of a printing machine for printing carriers, which method employs use of a printing foil having a hole system which has been aligned relative to the image center and being secured to a printing screen having locating bores which have been aligned relative to the image center and which correspond to locating pins of the printing machine which have been aligned relative to the carrier center, wherein the method comprises: a) the printing foil is provided with at least two registration marks which have been aligned relative to the image center and is secured to the printing screen in a substantially centered relationship, b) the printing screen is movably secured to an optical centering device comprising master pins which are positionally identical to the locating pins of the printing machine, c) the registration marks of the printing foil are brought in register with positionally identical registration marks of the optical centering device, d) centering elements are slid onto the master pins with an accurate fit, and e) the master pins provided with the centering elements are made to engage the radially enlarged locating bores of the printing screen with clearance and are secured in their centered positions. ### Claim 2 (depends on 1) The method as claimed in claim 1, wherein a) the printing screen with the printing foil is secured in a substantially centered relationship on a positioning table of the optical centering device, which table is movable in X-Y directions, b) the registration marks of the printing foil are scanned by two cameras arranged above the positioning table at the location of the registration marks and are displayed on monitors connected to said cameras, and c) the registration marks of the printing foil displayed on the monitors are brought in register with the positionally identical registration marks of the centering device which have been fixedly impressed upon the monitors. ### Claim 3 (depends on 1) The method as claimed in claim 1, wherein after the registration marks have been brought in register the centering device is lowered so far towards the printing screen that the master pins with the slid-on centering elements arranged on the centering device engage the radially enlarged locating bores of the printing screen. ### Claim 4 (depends on 3) The method as claimed in claim 3, wherein the centering elements are secured in the enlarged locating bores by means of a rapidly curing adhesive, or by means of a two-component adhesive, or by screwing, clamping, or (laser) welding. ### Claim 5 (depends on 1) An optical centering device for carrying out the method as claimed in claim 1, wherein a) the positioning table, which is movable in X-Y directions, has been arranged on a base plate of the optical centering device, b) a vertically movable bridge for carrying and holding the cameras and the master pins has been arranged above the positioning table, and c) the master pins provided with the centering elements are engageable in the radially enlarged locating bores by lowering said bridge in a vertical direction. ### Claim 6 (depends on 5) The centering device as claimed in claim 5, wherein the centering elements are centering sleeves, or locating plates. ### Claim 7 (depends on 5) The centering device as claimed in claim 5, wherein at its ends the bridge is mounted and supported in vertical guide rails so as to allow it to be lowered. ### Claim 8 (depends on 2) The method as claimed in claim 2, wherein after the registration marks have been brought in register the centering device is lowered so far towards the printing screen that the master pins with the slid-on centering elements arranged on the centering device engage the radially enlarged locating bores of the printing screen. ### Claim 9 (depends on 8) The method as claimed in claim 8, wherein the centering elements are secured in the enlarged locating bores by means of a rapidly curing adhesive, or by means of a two-component adhesive, or by screwing, clamping, or (laser) welding. ### Claim 10 (depends on 6) The centering device as claimed in claim 6, wherein at its ends the bridge is mounted and supported in vertical guide rails so as to allow it to be lowered.