COSMOS helps keep the fastest computer-to-plate printing system in the world running smoothly

Company Sonoran Scanners Industry Electrical/Electronics Location U.S.A. Product Used COSMOSWorks Type of Analysis Linear Static, Frequency More Details

The Challenge

Sonoran Scanners, in Tucson, AZ, makes computer-to-plate (CTP) systems for graphics arts applications, mostly in the newspaper industry.

Timothy Ellis, opto-mechanical engineer for Sonoran Scanners, says, "Computer-to-plate systems are used in the newspaper industry, book printing, and many commercial printing applications where they replace contact printers. The common method of plate production involves someone laying film over a printing plate, and then exposing the plate. With a system like the CactusSetter, computer-generated images and text go directly to an Ultraviolet (UV) plate for printing on an offset press."

The Solution
The CactusSetter has a moving optical system, which Ellis says "is very unusual. This makes the bridge one of the most critical part of the optics. We have to make sure the bridge is stable under transient conditions when the optics are moving, and statically stable with regard to gravity deflections." The bridge can't be allowed to sag, Ellis says, adding, "The amount of deformation allowable - if the stages are to continue to operate without binding - is 50X 10^-6 inches or approximately fifty-millionths of an inch. In addition, various kinds of hardware are added to the bridge and we have to make sure the additional weight doesn't cause sag beyond those extremely tight tolerances. The moving platforms, called translation stages, have to have smooth and repeatable motions."

Ellis has responsibility for the optic-mechanics in the system, and he uses COSMOSWorks, a leading design analysis program integrated with the SolidWorks CAD program, "on every part I design, and some of the more critical parts designed by the other engineers." He says that he uses the program to analyze the stiffness of the structures "both with regard to generalized flexure and natural frequencies, to ensure that they meet the system performance specifications."