APPARATUS FOR CUTTING HELICALLY WOUND METAL TUBING

摘要

2102627 9317803 PCTABS00025 In a machine for the production of helically wound tubing from a metal strip, the said strip is advanced within a helical forming head (22) to form a metal tube, and a cutting apparatus for severing the tube as it issues from the forming head (22) comprises an internal cutting blade (11) mounted at the end of a boom (8) extending within the forming head (22), and a rotatable external cutting wheel (17) mounted upon a drive shaft (15) that is coupled to a driving motor (20) via a cardan shaft (21). An extendable pillar (12) is arranged to raise and lower the cutting wheel (17) relatively to the cutting blade (11) in order to cause the blades (11) and (17) to overlap and cut a metal tube. The boom (8), pillar (12) and motor (20) are all carried on a common carriage (4) that is axially movable relatively to the forming head (22) when the cutting wheel (17) penetrates the wall of the metal tube. The carriage (4) may move passively with the tubing or may be driven in synchronism therewith by means of a servo drive synchronised with the speed of advance of the metal strip that is to form the tubing.