Method of making a tapered tubular member of flexible metallic foil

Claim 1

A METHOD OF MAKING A TAPERED TUBULAR MEMBER, SAID METHOD COMPRISING FEEDING A FIRST STRIP OF MATERIAL THROUGH COOPERATING ROLLERS AND DRIVING THE ROLLERS TO GRIP AND ELONGATE SAID FIRST STRIP LENGTHWISE THEREOF BEYOND ITS ELASTIC LIMIT WITH THE AMOUNT OF ELONGATION UNIFORMLY INCREASING FROM ONE LONGITUDINAL EDGE TO THE OTHER, AND AFTER EFFECTING SAID ELONGATION WRAPPING SAID FIRST STRIP A PLURALITY OF TIMES ABOUT A MANDREL HAVING A TAPER EQUAL TO THE GRADIENT OF ELONGATION BETWEEN SAID LONGITUDINAL EDGES AND WITH EACH SUCCESSIVE WRAP PARTIALLY OVERLAPPING THE PRECEDING WRAP AND THE STRIP HAVING A WIDTH WHICH IS A MINOR FRACTIONAL PART OF THE LENGTH OF SAID MANDREL, ELONGATING A SECOND STRIP OF MATERIAL LENGTHWISE THEREOF TO THE SAME EXTENT AS THE ELONGATION OF SAID FIRST STRIP, THEREAFTER WRAPPING SAID SECOND STRIP OVER THE FIRST STRIP WITH EACH SUCCESSIVE WRAP THEREOF PARTIALLY OVERLAPPING THE PRECEDING WRAP, REPEATING THE ELONGATION AND WRAPPING UNTIL THE DESIRED THICKNESS OF THE WALL OF THE TUBULAR MEMBER IS OBTAINED, SECURING THE STRIPS TOGETHER AT THEIR INTERFACES AND THEREAFTER SEPARATING THE TUBULAR MEMBER THUS FORMED FROM THE MANDREL.

Claim 2

A METHOD OF MAKING A TAPERED TUBULAR MEMBER, SAID METHOD COMPRISING FEEDING A FIRST STRIP OF MATERIAL THROUGH COOPERATING ROLLERS AND DRIVING THE ROLLERS TO GRIP AND ELONGATE SAID FIRST STRIP LENGTHWISE THEREOF BEYOND ITS ELASTIC LIMIT WITH THE AMOUNT OF ELONGATION UNIFORMLY INCREASING FROM ONE LONGITUDINAL EDGE TO THE OTHER, AND AFTER EFFECTING SAID ELONGATION WRAPPING SAID FIRST STRIP A PLURALITY OF TIMES ABOUT A MANDREL HAVING A TAPER EQUAL TO THE GRADIENT OF ELONGATION BETWEEN SAID LONGITUDINAL EDGES AND WITH EACH SUCCESSIVE WRAP PARTIALLY OVERLAPPING THE PRECEDING WRAP AND THE STRIP HAVING A WIDTH WHICH IS A MINOR FRACTIONAL PART OF THE LENGTH OF SAID MANDREL, ELONGATING A SECOND STRIP OF MATERIAL LENGTHWISE THEREOF TO THE SAME EXTENT AS THE ELONGATION OF SAID FIRST STRIP, THEREAFTER WRAPPING SAID SECOND STRIP OVER THE FIRST STRIP WITH EACH SUCCESSIVE WRAP THEREOF PARTIALLY OVERLAPPING THE PRECEDING WRAP, REPEATING THE ELONGATION AND WRAPPING UNTIL THE DESIRED THICKNESS OF THE WALL OF THE TUBULAR MEMBER IS OBTAINED, SECURING THE STRIPS TOGETHER AT THEIR INTERFACES AND THEREAFTER SEPARATING THE TUBULAR MEMBER THUS FORMED FROM THE MANDREL.