| 摘要 |
The invention relates to a sealing unit for heat-sealing two layers of film material. Said sealing unit comprises two endless conveying belts, which each have an outwardly facing first surface, wherein, during use, said first surfaces extend partly side by side each other such as to form two conveying surfaces facing each other, thereby enabling to clamp film material between said facing conveying surface parts. The sealing unit further comprises driving means for driving the two endless conveying belts in opposite direction of circulation, thereby enabling to carry film material clamped between the facing conveying surface parts in a film feed through direction. Furthermore, the sealing unit comprises at least one heating means for heating the film material. Said at least one heating means is provided adjacent to an inwardly facing second surface of a first one of the endless conveying belts, preferably at a position where the conveying belts are partly extending side by side each other during use. The driving means comprise two driving members for driving the first conveying belt, wherein said two driving members are located at least partly at opposite lateral sides of the at least one heating means. |
