| 摘要 |
PROBLEM TO BE SOLVED: To provide a welding machine capable of automatically welding a thermoplastic resin pipe from the inside thereof. SOLUTION: The welding machine 1 for the thermoplastic resin pipe K is equipped with a lifting and running support part 3 for supporting the main body 2 of the welding machine, so as to allow the same to run in the thermoplastic resin pipe K axially in an up and down liftable manner; a pair of upper drive leg parts 4, 5 mounted on the main body 2 to extend almost radially in a stretchable manner; a pair of lower fixed leg parts 6, 7 mounted on the main body 2 to extend almost radially, the welding part mounted on the main body 2 and welding the pipe K from the inner surface thereof; and a drive control part 9 issuing an operation command to the respective parts, so that the upper drive legs 4, 5 are brought to a contracted state so as to prevent the contact of the upper drive legs 4, 5 and the lower fixed legs 6, 7 with the inner surface of the pipe K, and the lower fixed legs 6, 7 are raised by the lifting and running support part 3 through the main body 2, and allowed to fall by the lifting and running support part 3 through the main body 2 by the lifting and running support part 3 when the welding part 8 arrives at a predetermined place to be brought into contact with the inner surface of the pipe K and, thereafter, the lifting and running support part 3 itself is raised and the upper drive legs 4, 5 are brought to an extended state to be brought into contact with the inner surface of the pipe K to weld the pipe by the welding part 8. |
