Bag manufacturing apparatus and method

A bag manufacturing apparatus (1) for manufacturing open-mouth bags (2), the bag manufacturing apparatus (1) comprising:

• a storage device (3) including a supply (4) of bag film (5),
• a conveying device (6) to selectively advance and retract the bag film (5) along a conveying path (7),
• a cutting device (12) including cutting means (13, 14) to separate a predetermined film length (15) of the bagfilm (5), wherein the separated predetermined film length (15) of the bag film (5) forms a bag body (16),
• a welding device (8) including welding means (9, 10) to weld a bottom seam (11) in the bag body (6) to form an open-mouth bag (2), wherein the cutting device (12) and the welding device (8) are disposed and effective in an overlapping longitudinal section (17) of the conveying path (7), and
• a control device (60) to control the conveying device (6) and the welding device (8) such that:
• after the cutting means (13, 14) of the cutting device (12) separates the predetermined film length (15) of the bag film (5) to form the bag body (16), the control device (60) controls the conveying device (6) to retract the bag film (5) a distance (37) along the conveying path (7) away from the bag body (16), and then
• the control device (60) controls the welding means (9, 10) of the welding device (8) to weld the bottom seam (11) in the bag body (6) after the conveying device (6) retracts the bag film (5), thereby forming the open-mouth bag (2).