Abstract: This invention relates to an engraving system and method for engraving a pattern using a plurality of engraving devices. The invention discloses apparatus and method for sequencing and engraving a plurality of engraving devices such that when the areas engraved by those heads meet they provide a continuous engraved pattern. The system and method also comprises an imaging system for imaging the engraved areas associated with each engraving head so that the heads or signals driving the heads may be adjusted to further facilitate providing engraved areas which appear as if they had been engraved by a single engraving head when, for example, the engraved area of one head meets the engraved area of another head. Also disclosed is a method for sequencing and transmitting image data associated with an image to be engraved in order to accommodate any cylindrical offset or the angular displacement between, for example, two engraving heads that are positioned in a generally opposed relationship.

Abstract: This invention relates to an engraving method and apparatus for engraving a cylinder for printing an intaglio pattern on a web of material. The engraver comprises a driver for rotatably driving the cylinder and a controller for controlling the operation of the engraver and for generating an intaglio engraving signal corresponding to the predetermined intaglio pattern. The engraver also comprises an engraving head comprising a stylus having a generally flat cutting edge or surface. The engraving head also is capable of engraving at response times of less than 200-300 microseconds, thereby enabling the engraving head to engrave the intaglio pattern on the cylinder during the rotation of the cylinder in response to the intaglio engraving signal. The apparatus and method also comprise a fine line boost routine for facilitating engraving fine areas or lines of the intaglio pattern. There is also provided apparatus and method for controlling ink flow in large engraved areas or intaglio trenches.

Abstract: The invention is characterized in that it comprises a toolpath generating routine and system for generating a plurality of control points directly from image data representing an image to be engraved. The control points are used to generate a toolpath which, in turn, will be used to energize an engraving head such that a tool or stylus will engrave a pattern of engraved areas in response to the toolpath. An engraving system and method for engraving at least one engraved area is shown having an engraving head tuner for tuning an engraving head such that the frequency characteristic of the engraving head defines a substantially constant gain for frequencies less than a predetermined frequency.

Abstract: An engraving system and method is disclosed having multiple engraving heads wherein the operation of each head is controllable so that a vertical screen and/or horizontal screen may be independently controlled, thereby facilitating enabling each engraving head to engrave in accordance with different screen rulings as may be selected by a user. The engraving system includes a signal generator for controlling the vertical screen by utilizing a plurality of vertical scalers which use a cylinder factor signal corresponding to the rotational position of a cylinder rotatably mounted on the engraver, as well as screen variables, such as a screen angle and a screen ruling, to generate independent vertical scaled or screen signals. These vertical scaled signals are used to independently energize the engraving heads to engrave patterns defining different vertical resolutions or vertical screens.

Abstract: A method and apparatus for automatically measuring a cylinder characteristic, such as a cylinder diameter or a cylinder run-out and then automatically adjusting the engraver in response to the measurement and subsequently engraving the cylinder to account for such characteristic. The engraver includes a run-out detector for detecting a cylinder characteristic of the cylinder on the engraver and the run-out detector includes an LVDT sensor and a run-out circuit for generating a signal generally corresponding to a shape of the cylinder surface. The run-out circuit is capable of generating a measured run-out using the signal generated by the LVDT sensor. The method and apparatus also provides a method and apparatus for automatically adjusting for the cylinder characteristic using manual, mechanical and/or electronic features of the method and apparatus.

Abstract: An engraving system and method for engraving a pattern, such as an intermeshing pattern, using a plurality of engraving devices is disclosed. The engraving system and method sequences and engraves the plurality of engraving devices such that when the areas engraved by those devices meet, they provide a continuous engraved pattern. The system and method also includes an imaging system and method for imaging the engraved areas associated with the engraving heads so that the heads or signals driving the heads may be adjusted to further facilitate providing engraved areas which appear as if they had been engraved by a single engraving head when, for example, an engraved area of one head meets an engraved area of other head. Also disclosed is a method and system for sequencing and transmitting image data associated with an image to be engraved in order to accommodate any cylindrical offset or an angular displacement between, for example, two engraving heads that are positioned in a generally opposed relationship.

Abstract: An engraving method and apparatus for engraving a cylinder for printing an intaglio pattern and/or non-intaglio pattern on a web of material. The engraver includes a driver for rotatably driving the cylinder and a computer for controlling the operation of the engraver and for generating an intaglio engraving signal corresponding to an intaglio pattern and a non-intaglio signal for a gravure pattern. The engraver also uses an engraving head for engraving the cylinder with the intaglio pattern and the gravure pattern during the rotation of the cylinder in response to the intaglio engraving signal and non-intaglio signal.

Abstract: This invention provides an engraving method and apparatus for engraving a plurality of cells which define a pattern defining at least one edge on a surface of a cylinder. The method and apparatus generate an edge signal corresponding to at least edge cell situated in a pattern defining at least one edge on the surface. The system and method may utilize a tabulator for tabulating a table of data corresponding to an image and a locator for locating the edge using the data. The system and method provide a signal generator which can cause the engraving location of an engraved area to be shifted to facilitate defining the at least one edge. Moreover, the signal generator may also cause the area to be reduced in order to change a predetermined characteristic of the area in order to better define the at least one edge.

Abstract: An engraver including an automatic tool changer and verification system for changing engraving tools on engraving heads. The engraver includes a turret having a plurality of workholders for holding a plurality of replacement tools. Some of the workholders are empty for replacing a worn tool from an engraving head on the engraver. When it is desired to change a tool on the engraving head, an empty tool holder is indexed to a tool changing position opposite the engraving head whereupon the worn tool is transferred from the engraving head to the tool changer. Thereafter, the tool changer is indexed to a position where a replacement tool is situated in opposed relationship with the engraving head. The tool changer includes a pneumatic system for causing the worn tools and replacement tools to be transferred between the engraving head and the tool changer. The engraver also utilizes a tool verification routine for verifying that a tool on the engraving head is the correct tool and/or is not defective.

Abstract: A method for aligning a cylinder support in an engraver includes a step of actuating a plurality of jaws to grip the cylinder support such that the cylinder support becomes automatically aligned in the engraver. The actuating step may further include the step of inserting the cylinder support a predetermined distance into a receiving cavity, where the predetermined distance may range from about 0-300 mm. The method is further characterized in that it may include steps of biasing the plurality of jaws to a predetermined position, energizing a cylinder to cause the plurality of jaws to move substantially simultaneously towards a rotating axis of the engraver; pivoting the pivot lever to cause the jaws to actuate toward and away from a rotational axis of the engraver; and/or lubricating the plurality of jaws with a lubricant and purging the lubricant associated with the plurality of jaws; and/or indexing each of the plurality of jaws to provide a desired travel range.

Abstract: A includes system and method for determining an actual volume measurement for an engraved area on a surface of a workpiece, such as a cylinder. The system and method is capable of capturing an image of an engraved area, determining a plurality of cross-section volumes for a plurality of cross-sectional areas using the image, and generating a plurality of volume values in response thereto. The system and method sum the volume for the plurality of cross-sectional areas to provide a total engraved area actual volume value. If necessary, the system and method causes an engraver to be adjusted during a set-up procedure or during real-time operation to ensure that the densities of the areas being engraved correspond to desired densities. A computer associated with the engraver utilizes an image to determine a stylus profile from which engraved area measurements can be determined.

Abstract: A method of engraving which accommodates changes in copper hardness, variations in head linearities, worn stylus, and the like. The method involves the cutting of midtone test cells, as well as highlight and full width test cells. The widths of the test cells are measured and used to establish slopes and offsets for adjustment lines, which in turn are applied inversely to transform a desired cell width into an engraving drive signal. The technique assures that the computed engraving drive signal will produce the desired cell width.

Abstract: A universal cylinder mount for mounting at least one a plurality of cylinders between a headstock and a tailstock of an engraver. Each of the cylinders has a mounting aperture at each end adapted to receive a universal cylinder mount associated with each of the headstock and tailstock. The universal cylinder mount is adapted to accommodate a plurality of mounting apertures formed with different sized and having various sloped walls for facilitating alignment and frictional gripping engagement of the cylinders. The universal cylinder mount comprises at least one helically-shaped spiral or engaging edge to facilitate reducing or completely eliminating the seizing action between the cylinder aperture and the universal cylinder mount of the cylinder when the mounts are rotated in a non-engraving direction or are moved away from the mounting surfaces.

Abstract: An engraving system and method having a non-volatile memory loaded with error coefficients. The error coefficients represent previously experienced differences between computed cell configuration values and corresponding configuration values for cells actually engraved. Sets of error coefficients are tabulated and stored in the memory along with associated setup parameters. Setup of the engraving system for a new job is swiftly accomplished by using values of the setup parameters to retrieve sets of approximate error coefficients, from which interpolated values are obtained. The interpolated values of the error coefficients then are used for calculating configuration control parameters such as AC gain, video gain and white offset.

Abstract: An engraver having an engraving signal generating system for engraving a workpiece. The engraver includes a setup circuit enabling direct dimensional control of the cavities engraved by the engraver. Controls are provided for setting at least one of a plurality of parameters, such as a black cell width, a black channel width and a highlight cell width. These parameters are fed to the setup circuit which translates them into multiplication factors for an AC signal and a video signal. The multiplied signals are combined with an offset signal to produce an engraving signal.

Abstract: A platform for supporting an engraving head in a manner accommodating translational movement without any associated rotation. The platform has a deck which is supported by a pair of flexible support columns. In operation the platform is situated alongside a rotating printing cylinder. The engraving head is mounted on the deck of the platform and is provided with a guide shoe which rides against the surface of the printing cylinder. As the cylinder rotates to angular positions having different radii, the engraving head responds with a purely linear reaction. Consequently the engraving head is able to engrave uniform-depth cavities in the surface of the printing cylinder. In two alternative embodiments the deck is driven by a resilient link arrangement which is coupled to a leadscrew and carriage assembly.

Abstract: A method and apparatus for automated loading and unloading of a cylinder in an engraver. The method and apparatus permit the engraver to accommodate cylinders of differing geometries, including a range of lengths, diameters and mounting configurations. The engraver includes a headstock and a tailstock which cooperate to rotatably support a cylinder at an engraving station in the engraver. The engraver includes a cylinder handling system having at least one cylinder supporting the cylinder between the headstock and the tailstock during the loading and unloading of the cylinder. The cylinder handling system includes a driver for driving the cylinder support towards and away from the engraving station until the headstock and the tailstock engage and rotatably support the cylinder. Once the cylinder is rotatably supported between the headstock and the tailstock, then the cylinder support is retracted.

Abstract: An error detection apparatus and method for use with engravers, such as gravure engravers. An error value E corresponding to the difference between a set of predetermined setup parameters and actual measurement of a portion of an engraved area on the cylinder is determined. The error value E is then used to adjust the engraver to engrave an actual cut or etch in accordance with the set of predetermined setup parameters. Advantageously, an error detection and correction system is suitable for providing a closed-loop system for engraving a cylinder. The apparatus and method may be used during initial setup or during normal operation of the engraver. Other features include an autofocus routine to facilitate the auto-focus procedure. Also, image processing is further enhanced by gap filling, discontinuity removal, and light calibration methods which may be used alone, in combination with each other, or in combination with the automatic focus system and/or automatic shoe system.

Abstract: An error detection apparatus and method for use with engravers, such as gravure engravers. An error value E corresponding to the difference between a set of predetermined setup parameters and actual measurement of a portion of an engraved area on the cylinder is determined. The error value E is then used to adjust the engraver to engrave an actual cut or etch in accordance with the set of predetermined setup parameters. The error detection and correction system a closed-loop system for engraving a cylinder. The apparatus and method may be used during initial setup or during normal operation of the engraver.

Abstract: A system and method relates to an ink volume determination for determining the amount of ink to be applied by the printer. The ink volume determination involves generating a composite cylinder layout of at least one image for the engraved cylinder, generating a set of data corresponding to the composite cylinder layout and then using the set of data to determine the volume of ink. The printer is then filled with a volume of ink related to this calculated ink volume during a printing process. The method of determining ink volume may be used independently of the printing process, for example, in order to control or manage the amount of ink used in the printing press.