Folding apparatus for folding a hem on a sheet of material

摘要

Hemming apparatus (1) for forming a hem (5) on a sheet (2) of heat weldable plastics material comprises a base plate (15) and a jig plate (16) which between them define a passageway (20) for the sheet (2). The jig plate (16) defines a hem forming edge (30) extending from an upstream position (31) to a downstream position (32) along which the hem (5) is progressively formed. A guide surface (36) urges the sheet (2) against the hem forming edge (30) and a hem folding member (45) forms and retains the hem (5) parallel to the sheet (2). Welding apparatus (7) forms the seam weld.