ELECTRIC FUSING METHOD AND APPARATUS THEREFOR

• Main Authors: BAI HIDEKI, NISHIKAWA KOZO, SHIBUYA AKIYA
• Format: Patent
• Language: English
• Published: 02.06.1999
• Edition: 6
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; BLASTING; ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULARARTICLES; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; JOINTS OR FITTINGS FOR PIPES; LIGHTING; MEANS FOR THERMAL INSULATION IN GENERAL; MEASURING; MECHANICAL ENGINEERING; PERFORMING OPERATIONS; PHYSICS; PIPES; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; TESTING; THERMAL INSULATION IN GENERAL; TRANSPORTING; WEAPONS; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

PROBLEM TO BE SOLVED: To accurately control the thickness of a melt layer in the joined part of a fused joint and a pipe. SOLUTION: The joined parts of a fused joint 12 made of a synthetic resin having first and second heater members embedded therein and pipes 14, 16 made of a synthetic resin are melted by the electrically heated by first and second heater members. Then, ultrasonic pulses are allowed to be incident on the fused joint 12 from the outer peripheral surface thereof in the thickness direction of the fused joint 12 and the pipes 14, 16 on the way of melting by an ultrasonic probe 18 and the reflected signal from the upper interface of the melt layer formed on the joined parts of the joint 12 and the pipes 14, 16 is detected by setting a gate and the level of the detected reflected signal is compared with a reference level to judge whether the melt layer reaches a predetermined thickness. When the melt layer reaches the predetermined thickness, the heating of the first and second heater members is stopped.