Verfahren zur Herstellung einer Verbindung zwischen den einander zugewandten Oberflächen zweier Glieder aus thermoplastichem Material, Vorrichtung für die Durchführung des Verfahrens, nach diesem Verfahren hergestellte Verbindung und Verwendung des Verfahrens

摘要

942,592. Seaming non-metallic sheet material. TELEPHONE CABLES Ltd. May 11, 1962 [May 24, 1961], No. 18784/61. Heading B5K. [Also in Division H2] A joint is formed between facing surfaces of two thermoplastic members 1, 3 by interposing an electrical heater 5 of coherent open-work form between the two surfaces, fusing the material at the interface between the surfaces by the heater 5 and then withdrawing the heater with a motion which is agitated during at least an early part of the withdrawal. To join two lengths of polythene-sheathed cable, the sheath is cut back to expose the conductors 2 which are joined and a polythene sleeve 4 previously applied over the cable is slipped over the joint. A polythene collar 3 may be provided for each end of the sleeve 4. To join the collar 3 to the sheath 1 the heater 5 is interposed therebetween and a tape 6 is applied under tension to the outside of the collar. The heater 5, Fig. 2, comprises a stainless steel mesh strip cut on the bias and has an unstretched diameter slightly less than that of the sheath 1. A carrier 9 carries the heater 5 by strips or pins 8 and connecting leads 7 secured thereto. The tape 6 may comprise a length of silicon elastomer or neoprene tape having a bias cut stainless steel heater 10 secured thereto and being of such a length that its ends overlap. The inner end of the tape 6 is preferably tapered. The collar 3 is first softened at a temperature between 60 ‹ and 85‹ C. by the heater 10 and the heater 5 heats the material at the interface to a temperature between 150‹ and 180‹ C. to form the joint. The heater 5 is withdrawn by combining both axial and to-and-fro angular movement along the cable axis, the tape 6 still applying pressure. The heater 5 is cut from the cable and the carrier 9 and the tape 6 are removed. Similarly, the sleeve 4 is joined to the collar 3 at A. The heater 10 may be dispensed with and preliminary softening may be obtained by initially running the heater 5 at a low current. In a modification, Fig. 5, the tape 6 is wound without tension and a closed, rectangular crosssection pneumatic tube 12 is applied around the tape 6 and is constrained against movement by U-section members 13 articulated together. Pneumatic pressure is admitted through a port 14 and the tube ends overlap at 121.