Process and apparatus for joining polymer materials at a high welding speed

Abstract

Process and apparatus for joining endless polymer materials by means of the transillumination technique. According to the invention, in order to be joined, the endless materials are guided through two contrarotating rollers that press against each other. The first roller consists of a material that is transparent to laser beams and is tubular. The second roller is formed from a material that can be deformed easily at the surface, so that its surface can adapt to the shape of the first roller. Devices for producing a laser beam at the contact surface between the materials to be joined are arranged in the first roller. In this case, the beam is formed as a linear laser beam longitudinally with respect to the direction of movement of the materials so that during the passage, continuous heating of the material up to the melting point is achieved, without an excessively high laser output having to be provided. By means of the process and the apparatus, continuous joining is possible at high speed.

Dependencies are inferred from the claim text.