Patent ID: 6811632
Filing Date: 2004-11-02
Classification: B29C,B29K,B29L

Abstract:
A method for welding thermoplastic material comprising;rotating an element and directing the rotating element into a thermoplastic material and advancing the rotating element along a path in thermoplastic material where a weld is to be formed, the element having a geometry, and rotated at a speed and advanced at a rate relative to the thermoplastic material such that the rotation of the element against the thermoplastic material introduces frictional energy into thermoplastic material in a weld forming region sufficient to heat the thermoplastic material in the weld forming region to a temperature to fuse thermoplastic material, constraining the thermoplastic material in the weld forming region with a constraining surface directed along the path that has a motion independent of rotating motion of the rotating element, such that the independent motion and construction of the constraining surface inhibit expulsion of heated thermoplastic material from the weld forming region resulting from the rotation and advancement of the element, inhibit lateral forces induced in the rotating element from the constraining surface, assist in consolidation thermoplastic material that is heated and fused.