Automation with highest precision
The assembly and gluing of various plastic components occurs at the beginning of every product. This preparatory work includes the assembly of three components: nut (in square or hexagon design), threaded rod and washer. The result: a highly versatile, plastic threaded bolt for various thread sizes and lengths. Since a thermoset plastic cannot be welded, a special adhesive is used to bond the components. More than anything, this work step demands the highest precision. WKT’s goal was to automate this work step, reduce the defect rate to zero percent and thus increase productivity.
KUKA robot checks own work independently
A square or hexagon nut is first picked up and positioned in the holding fixture. The threaded rod that is then picked up is chamfered and turned 180 degrees in order to add adhesive to the underside in a subsequent step. This end of the threaded rod is then screwed into the nut under torque control. The two elements – nut and threaded rod – then become a single joined component. In a final step, the washer is added. For this, the robot picks up the washer and lets it slide over the threaded rod and down onto the nut. This is how, in just a few steps, the finished threaded bolt is created in the holding fixture. Thanks to camera technology, the robot is capable of independently inspecting the product. In this manner, the precision of the work can be checked and a reject or good part can be determined within seconds. The finished bolt is removed from the holding fixture in order to take up its final position in the curing device.