Patent ID: 6256851
Filing Date: 2001-07-10
Classification: B21C,B23D,Y10T

Abstract:
An apparatus for forming helical tubes having a given length, said apparatus comprising at least one first flanging station for producing a flange along at least one side edge of a metal strip, a forming tool which receives a flanged metal strip from the flanging station and bends the flanged metal strip into a helical configuration, a crimper which crimps together adjacent edges of the helical strip to form a spiral tube, and a cutter which cuts the formed spiral tube into lengths corresponding to said given length, said cutter comprising a measuring arrangement for determining the length of the spiral tube to be cut off, said measuring arrangement comprising a first measuring device which opto-electronically senses said spiral tube and a second measuring device which mechanically senses said spiral tube;wherein said second measuring device comprises a pivotable stop which comes into contact with a leading end of said spiral tube and is pivoted through a given angle by forward movement of said spiral tube, said second measuring device emitting a control signal to activate said cutter when said pivotable stop is pivoted through said given angle.