PURPOSE: To expand a strip efficiently, precisely and uniformly.
CONSTITUTION: Opposite edge portions and center portion of a strip 22 are progressively sheared along a laterally extending slits 24 and 26 which are longitudinally spaced, and each of opposing U-shaped tabs 28 whose edges 31 are connected each other is successively connected at their center portion 33. The edges of the strip 22 are gripped by two pairs of pinch rollers 38 which are co-axially located, and the center portion of the strip is gripped by a pair of pinch rollers 48 which is located longitudinally offset later than the pinch rollers 38 located at both edges. The central pinch rollers 48 are driven at a higher peripheral speed to expand the U-shaped tabs into V-shaped ones.
GEM CITY ENG CO (US)
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