APPARATUS FOR CUTTING HELICALLY WOUND METAL TUBING

摘要

In a machine for the production of helically wound tubing from a metal strip , the said strip is advanced within a helical farming head (22) to form a metal tube, and a cutting apparatus for severing the tube as it issues from the forming head (22) com- prises an internal cutting blade (1l) 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 ex- tendable pillar (12) is arranged to raise and Power the cutting wheel (17) relatively to the cutting blade (11) in order to pause 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 carri- age (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 i n synchronism therewith by means of a servo drive synchronised with the speed of advance of the metal strip that is to form th e tubing.