| 摘要 |
Apparatus has a unit punching out a plastic sheet with centre fold line and an end and two side flaps on one half, a locating table (6) for positioning (8,11) the half with flaps, a lifter (9) to carry and fold over the second half, and two further members (10) to fold over the side flaps onto the second half when this has been folded over onto the first. A welding unit (18) is located above the table to weld the flaps after folding over. The sheet is for example of semi- rigid PVC with carbon filler and is pretreated to reduce accumulated electrostatic charge. The sheet may be laminated to a lining of nonwoven polyester or polypropylene fabric. |
