Of the many methods used for welding thermoplastic parts, vibration welding continues to be one of the most popular since its introduction in the early 1970s. Vibration-welded parts can be found extensively in automobiles and medical devices, and increasingly in white goods and consumer products. One reason is vibration welders can handle parts as large as 2 by 6 feet.
For example, several years ago, Forward Technology developed two custom vibration welders for a large appliance manufacturer. Doug Grabinger, project manager at Forward, says the welders assemble tubs for front-loading washing machines. A large, stationary six-axis robot is positioned in front of each welder. Between the robots is a dual pallet-transfer system that brings sets of unwelded parts into the work cell on conveyor one (furthest from the robots) and moves welded tubs out of the cell on conveyer two. A separate conveyor for rejected tubs is located behind each robot.