Abstract: The invention relates to a laser head (11) for connecting tubular parts (1, 3, 12, 13) by the laser transmission method and to a method of connecting the tubular parts (1, 3, 12, 13) by means of the laser head (11). The laser head (11) and the method that can be performed by the laser head (11) are suitable in particular for connecting a connecting element or branching element (1) to one end of a plastic pipe (3). The laser head (11) makes simultaneous welding possible and has at least two shell parts (16) that can be radially separated from each other so that the laser head (11) can be placed around a connecting section (4) or a connecting region (15) of the tubular parts (1, 3, 12, 13). A number of laser sources (17) are arranged in the shell parts (16) in such a way that the laser beams (7) emerging from the laser sources (17) overlap at the connecting section (4) or at the connecting region (15) of the parts (1, 3, 12, 13).

Abstract: The hand-held hot air device, preferably for the local heating of thermoplastic materials, with a housing that forms a wand-shaped handle part with air inlet openings, and with an air guidance tube that protrudes from the handle part and radially delimits an air canal, with an electric heating element contained in the air guidance tube and an electric motor with a fan wheel contained in the handle part, and with an electronic control system arranged inside the handle part with one semiconductor power switch each arranged upstream of both the heating element and the electric motor, and with a display screen and an operating device for the hand-held hot air device arranged on the outside of the handle part.

Abstract: The invention relates to an electric hot wedge (1) for a welding device for the seam-like connecting of plastic webs, having a welding wedge (2) and a welding wedge attachment (3) made of metal, wherein the welding wedge (2) comprises at least one electric heating resistor (13) having a heating conductor (16), which is bonded to a ceramic carrier (15) as a conductive layer (12) and is preferably protected by a ceramic cover layer. According to the invention, the welding wedge attachment (2) has a support structure (28) made of metal on the side thereof, which substantially extends across the entire length and/or width of the electric heating resistor (16) and which mechanically stabilizes the carrier (15) of the heating resistor (16).

Abstract: An induction connecting sleeve for connecting weldable thermoplastic elements by means of fusion, with at least two sockets for the insertion of connection sections of the thermoplastic elements to be connected, and with an induction heating element embedded in the sockets, with operative sections of the induction heating element surrounded completely by a weldable thermoplastic material, and with the induction heating element arranged coaxially to the sockets. The induction heating element may be manufactured of metallic material with spring characteristics and to embed it under pre-tension in the thermoplastic material of the sockets. When the induction heating element is heated and the thermoplastic material of the socket of the induction connecting sleeve is plasticized, the induction heating element relaxes which causes radial pressure to build towards the connection section.

Abstract: The invention relates to a hand welding extruder (1) for welding thermoplastic materials by means of a plasticized plastic strand (26) having a plasticization worm unit (24) connected to a drive motor (20) by a gearbox (21), and having a hot air generation device (27) with an external air supply, the plasticizer worm unit, the gearbox, the drive motor, and the hot air generation device being disposed in a common housing. The proposed hand welding extruder has a bar-shaped housing having a front welding segment (7) and a grab handle (8) connected thereto in the longitudinal direction. The plasticizer worm unit and the hot air generation device are disposed in the bar-shaped housing in the welding segment and an electric motor (20) is disposed in the grab handle. The electric motor is connected to a shaft of the extruder worm (23) via a gearbox, the gearbox being potentially provided in the grab handle and/or the welding segment of the bar-shaped housing of the hand weld extruder.

Abstract: The invention relates to a method for determining the temperature-dependent state, in particular the melt state and/or the melt quantity of thermoplastic material when producing a weld seam (6), for example for joining thermoplastic parts (7, 7?) by means of a plastic welding device. For process control purposes, a temperature-dependent electric state variable of the thermoplastic material of the plastic parts (7, 7?) is measured continuously with and without applying heat to the plastic parts (7, 7?) along the weld seam (6) and compared to a target value or to benchmark values. In the method according to the invention, the electric state variable that is used is preferably the permittivity of the plastic parts (7, 7?). The permittivity is determined by means of the capacitor assembly (1) wherein the plastic material is used as the dielectric between the electrodes (3, 4) of the capacitor assembly (1).

Abstract: A laser diode structure for generating a collimated or divergent laser beam, preferably for application in gas detection, with a laser diode arranged in a closed housing, with the housing comprising a housing bottom, an exit window, electrical connections, a temperature control device for the laser diode, and an optical element for influencing the laser beam. The temperature control device carrying the laser diode is arranged on the housing bottom and the optical element is positioned at a distance from the laser diode. The invention proposes an electrically controllable power device for the cyclic alteration of the position and/or alignment of the optical element in relation to the laser diode so that the optical path length for the laser beam in the housing changes periodically.