Device for welding thermoplastic workpieces by electromagnetic radiation, particularly by infrared radiation

摘要

Welding unit to bond two thermoplastic workpieces along their joint (16), using an infra red electromagnetic radiation, has at least one resistance (10) with a profile which matches the geometry of the joint as closely as possible. The welding unit to bond two thermoplastic workpieces along their joint (16), using an infra red electromagnetic radiation, has at least one resistance (10) with a profile which matches the geometry of the joint as closely as possible. The passage of an electric current generates infra red heat to give a superficial melting to the thermoplastic surfaces. The resistance is mounted at a carrier (14), which is composed of at least one metal wire core within an insulating mantle to make contact with the resistance, without a short circuit between at least two points. This gives a continuous heating action, especially by crossing those portions of the wire at the entry/exit of a closed joint line. The wire is sufficiently flexible to give radius curves up to 1.5 mm.