| 摘要 |
Apparatus for welding portions of overlapping synthetic thermoplastic sheets 2, 2a which confine rows of stacked stationery products between them has two pairs of endless toothed belts 1, 1a, 101, 101a which engage the overlapping portions of the sheets from above and from below, a heated severing and welding tool 8, and a motor 9 which pivots the tool into and from the space between the two pairs of belts. The tool has an elongated severing edge 12 which is flanked by two heated bonding surfaces (13, 14 Figure 2) facing counter to the direction of transport of the sheets when the tool is held in the operative position between the two pairs of belts. At such time, the severing edge is inclined with reference to the plane of the overlapping portions of the sheets. A cooling device 118 is provided to direct compressed air against a guide for the belts at the severing and welding station so as to prevent adherence of severed surplus to the tool and/or to the seam or seams which are formed by the bonding surfaces, depending upon whether the tool is used between two rows of products or along an exposed lateral portion of a row. <IMAGE> |
