UN APARATO PARA PLEGAR UNA LAMINA DE MATERIAL FRAGIL CON EL OBJETO DE FORMAR UN SOBRE.

摘要

An apparatus for folding a sheet of relatively brittle material in which an articulated frame assembly is mounted relative to a support structure in a manner so that two portions of the frame assembly can pivot relative to each other in an angular direction to fold the sheet about a fold line intermediate the ends of the sheet. Each portion of the frame assembly includes a movable portion which is adapted to fold the outer end portion of the sheet about an additional fold line intermediate the first fold lines and the outer edge portion. The sheet is heated along the fold lines prior to the folding operations.