Apparatus for forming sheet metal duct work

Abstract

Apparatus is provided for forming sheet metal ducts of varying conical configuration from pre-cut blanks having a baseline and element lines thereon. The apparatus comprises a frame supporting independent axially aligned feed rolls. Each roll is power driven by separate variable-speed motors providing for a different feed rate at each edge of the blank being formed. The driven sections of each feed roll are adjacent at the center of the axially aligned rolls. Idler rolls around the drive shaft form the remaining length of each roll. Corresponding segmented pinch rolls spaced axially at the center are arranged to pinch the blank to be formed against the feed rolls. Sensors are positioned between the spaced ends of the pinch rolls to detect the position of the blank baseline and the angularity of the element lines. The feed and pinch rolls are mounted on bases provided with bearings permitting axial shifting to maintain the blank baseline at the established position relative to the frame. A bending roll is spaced from the feed roll and adapted to have its axis positioned at an angle to the feed roll to produce a different radius of curvature at each edge of the blank as forming progresses.

Dependencies are inferred from the claim text.