Abstract: A lapel provided at the one end of a paper sheet to forming a paper bag is introduced into the interior of an opening on the rotary cylinder by means. The folding blade has a rotational axis located outside the rotary cylinder parallel to an axis of rotation of the rotary cylinder. The thus bent lapel is brought in pressure contact with the edge face of the opening by means of a holding pawl which turns in operative association with the rotary cylinder. Thereafter, the lapel is covered and depressed by means of a depressing pawl which turns in operative association with the rotary cylinder whereby the lapel and a part of the paper sheet are adhesively secured to one another to build a double-walled structure around the opening of the paper bag.

Abstract: A forming assembly for automatic machines for forming boxes from semi-finished flat blanks, comprises a plate support with associated suction means for the semi-finished blanks and a forming mould for the erection of the parts of the semi-finished blank intended to constitute the side walls of the box.The forming mould has simplified longitudinal and transverse forming elements which are adjustable in length, width and height, and the plate support has spring feet supported by modular blocks releasably fixed to the sides of the plate. The plate support also has suction members connectible by a system of external tubing to a vacuum source.