Abstract: An upper contoured die which mates with a lower contoured die is rotated relative to and against the lower die to progressively squeeze and deform a softened thermoplastic sheet. The two dies create sharp detail on both surfaces of the deformed sheet without tearing the sheet.

Abstract: An apparatus for roll forming of thermoplastic material is provided which employs a pair of rollers having forming surfaces thereon, the pair of rollers defining a gap through which the thermoplastic material is to be passed during the forming operation, the thermoplastic material being dielectrically heated to a softening temperature as it passes between the rollers by a radio frequency electromagnetic field produced between the rollers by activating a radio frequency generator or oscillator which is electrically connected to one of the rollers, the rollers each having conductive portions between which the electromagnetic field is produced.

Abstract: An apparatus and method for continuously fabricating lightweight structural panels and the structural panel fabricated thereby are provided, the apparatus being capable of heating a core sheet to a temperature at which the sheet will be plastically deformable such that a corrugation forming means comprising a cylindrical forming drum having a plurality of annular recesses and a plurality of forming mandrels will form a plurality of axially extending corrugations.

Abstract: A displacement transducer is used to continuously monitor the distance between two fixtures securing parts to be welded. The signal from the displacement transducer is used to stop the welding process when a desired amount of material has been extruded from the weld. The control strategy will automatically take into account part nonuniformities that normally result in poor welds in welding processes that use time as the control variable.

Abstract: Thermoplastic panels are formed and laminated together simultaneously by using a roller to provide vertical pressure to two heated thermoplastic sheets, one a composite thermoplastic sheet, the other a monolithic thermoplastic sheet. The monolithic thermoplastic sheet allows laminating protective layers to structural panels for improving scratch resistance, improving appearance or reducing chemical permeability.