IMPROVEMENT OF PERFORMANCES OF AN OPTICAL SYSTEM FOR DEFECTIVENESSSURVEY IN A COMPANY OF THE AUTOMOTIVE FIELD

摘要

Laminated safety glass is widely used in thernautomotive field, while the demand of tempered glassrnis quickly increasing. Glass production is characterizedrnby several phases with grate temperature ranges. Alongrnthe productive process, the car windshields are subjectrnto scratches, abrasions, chippings, contaminations,rninclusions, impurities, pond points and bubbles. Forrnexample, pond points can be found on the glass platernbefore starting the productive process, due tornunqualified suppliers; instead other defects can appearrnlater during production activities. In the temperedrnglass production, particular furnaces are used for thernbending and the tempering, so each product has to berntested at the furnace exit, in order to control thernthermal and temporal parameters of the bendingrnprocess. The control of the optical quality of the glassrnproduction, can be realized by automatic systems ofrninspection. In the last years, the above control systemsrnhave become more and more fast, reliable, exact andrncheap; so they can be easily used for the quality controlrnin the glass production. Safeglass? is an automaticrnsystem of vision able to check anomalies and removerndefective components from the productive line. Thernabove system is able to “see” different kinds of defects:rnpond points (size from 0,5 mm), contaminations andrninclusions (size from 0,4 mm). Thanks to that system,rnit is possible to save production costs, discardingrndefective glasses at the beginning of the process,rnbefore other activities are realized with consequentlyrncost increase; moreover, by studying the kind ofrndefects, we can identify where the process is out ofrncontrol. The Safeglass? system can be easily installedrnin a standard productive line.