| 摘要 |
A JIG for WELDING MITERED JOINTS BETWEEN the MEMBERS of MOLDED PLASTIC WINDOW and DOOR FRAMES of the DISCLOSURE A jig for welding mitered joints between members of molded plastic window and door frames, comprising four mutually positionable clamp assemblies, one to each corner of the frame, each of which comprises a pair of horizontal rests serving to support the members of the frame, and respective upwardly-projecting fences disposed transversely and parallel to the horizontal exit path followed by the frames, that register with the external faces of the rails and the uprights of the frame; each clamp assembly further comprises a pair of plates, located above the corresponding pairs of rests, that serve-to hold the frame members fast against the rests as and when necessary. The fences disposed transversely to the exit path of the welded frame are embodied independently of the relative rests, and capable of movement between a first limit position, in which the rails are checked, and a second limit position in which the rails are freed and the fences themselves completely clear of the frame's transverse dimension. fig 1 |
