The protective loop (4) pivots about a horizontal axis (7) lying transversely with respect to the direction of travel. It moves between the vertical resting position (6) to the horizontal safety position. On finishing operations, the loop swings back autom...

The side loops (5) are of a modified U-shape, with the open ends of the U-shapes fastened to pivot blocks on the ends of a transverse shaft (7). The shaft rotates in a support tube (8) with a square cross-section and a circular bore. A lever plate (13) is ...