New Approaches to On-Line Parts Inspection. (Keeping up with Injection Molding).

Three new visual parts-inspection systems were demonstrated at the recent K 2001 show in Dusseldorf, Germany. First, Husky Injection Molding Systems Ltd. of Bolton, Ont., and Pressco Technology Inc. of Cleveland partnered in developing a real-time inspection system for PET preforms. At Husky's Bolton lab, Pressco's Intellispec-PSW3 in-line inspection system is integrated downstream of Husky's Index 250 preform injection machine (see photo), which runs a 48-cavity mold in a 10-sec cycle. The still-developmental system will provide automatic 100% parts inspection with defect identification and trend data for individual cavities.

Second, the Japanese parent of Nissei America Inc., Anaheim, Calif., showed a new inspection system that checks parts for short shots. Products are accumulated in a batch made up of a number of shots set by the molder. A special traversing robot grabs the last part of the batch from the mold and presents it to a camera. The camera takes a snapshot of the part area related to end-of-fill, and transmits the image to a data collector. Software compares the image with a good part and signals whether to accept or reject the batch.

Third, the German parent of Demag Ergotech Inc., Strongsville, Ohio, teamed up with Weiss Tecnik of Germany to demonstrate a new camera option for real-time 100% parts inspection. A take-out robot hands off the product to another robot, which moves the part to an inspection area beside the press. Two CCD cameras examine surface quality and dimensional accuracy. The robot drops an approved part on a conveyor or a rejected part in a bin for reprocessing. The cameras measure up to 100 points per part or as few as two points per part from 50 cavities.