| 摘要 |
PURPOSE:To decrease and average residual stress at a connection part of a coupler and the center of a coupler main body by forming an exhaust nozzle of melt in a groove as well as forming the groove circulating around on the coupler main body made of thermoplastic resin macromolecule material provided with a helical coil of thermoplastic resin macromolecule material with a lineal exothermic body built in it. CONSTITUTION:A helical coil 3 made of a covered wire 2 covering a lineal exothermic body 1 with a thermoplastic resin macromolecule material is provided on both end part inside surfaces of a coupler main body 4 made of the same thermoplastic resin macromolecule material, a groove 5 circulating around along the end edge of this inside surface is formed and an exhaust nozzle 6 open to both end surfaces of the coupler main body 4 is formed adjacent to the groove 5 from the outside of the helical coil 3. The lineal exothermic body 1 is a nichrome wire, carbon fiber or the kind. Consequently, melt never overflows through clearance gap when electrified, residual stress at connection part and others is averaged and shock resistance is improve, and pipes can be connected with accuracy heightened. |
