BUTT-WELDING METHOD OF THERMOPLASTIC RESIN PLATE, BUTT-WELDING APPARATUS OF THERMOPLASTIC RESIN PLATE, BUTT-WELDED THERMOPLASTIC RESIN PLATE

摘要

PROBLEM TO BE SOLVED: To provide a welding method which does not cause defects of the formation of a recess at an abutting surface when the abutting surface is subjected to high frequency induction welding by butting the end faces of a plurality of thermoplastic resin plates and the defects of warpage when the welded part of the abutting surface shrinks after high-frequency induction welding.SOLUTION: The end face 12c of a first electrode plate 12a is directed upward, and its both sides are held between insulated heat insulating materials 13 and 13 to form an anvil. On an end face 12c of the first electrode plate 12a of the anvil, butting parts of a pair of thermoplastic resin plates 20a and 20b which are welded are mounted. The lower surface of a second electrode plate 14 is arranged on the butting part and pressed. While the butting parts of the thermoplastic resin plates 20a and 20b are held between the end face of the first electrode plate 12a and the lower surface of the second electrode plate 14, a high-frequency current is fed between the end face 12c of the first electrode plated 12a and the lower surface of the second electrode plate 14, and the butting parts of the thermoplastic resin plates 20a and 20b are subjected to high-frequency induction heating and welded to each other.