摘要 |
An apparatus for automatically welding corrugated membranes of a type in which a welding torch is mounted on a head attached to the welding apparatus proper by way of an arc gear segment and the arc gear segment is driven through a pinion gear, whereby the head is moved along the arc gear segment to control the position of the torch. The arc gear segment is driven for angular movement by a drive motor mounted in the welding apparatus proper, and the arc gear segment includes a pair of rotatable small wheels provided at the ends of the arc gear segment and a cord such as a chain or rope extended around the small wheels and along the arcuate teeth of the arc gear segment, the middle portion of the cord being securely attached to the head adapted to be movable along the arc gear segment, whereby when the arc gear segment is rotated, the head attached to the cord is simultaneously moved through an angle which is two times that of the arc gear segment. |