| 摘要 |
<p>1,098,101. Making bags; seaming non- metallic sheet material. K. H. HONSEL. March 2, 1965 [March 2, 1964], No. 8886/65. Headings B5D and B5K. In the manufacture of bags, two or more welding stations carried on the periphery of a rotating drum 10, Fig. 1, seal one or both ends of tubular pieces 1 of plastics material positioned on the drum with their axes parallel to the axis of the drum. The workpiece 1 is fed between bands 4 and 5 to one of the welding stations on the drum 10, and after the welding has been completed, is removed between bands 4 and 28, ejector rollers 29, 30 feeding the workpiece to a delivery band 31. At a welding station, Fig. 2, an end of a workpiece 1 is clamped and welded between a fixed jaw 11 and a vertically reciprocating jaw 14, operated through a shaft 17 by a piston 22. The movable jaw 14 may be unheated, serving merely to press the workpiece against the heated jaw 11. The jaws may be mounted on the peripheral surface or the end face of the welding drum. Additional welding jaws may be mounted on the drum parallel to its axis. Each welding jaw 14 is actuated by a corresponding cam 43 closing switch 44; current is supplied to jaw 11 by cam 47 closing switch 45. The switch also operates a time delay relay which subsequently switches the current off. The jaw 14 may be raised when the current is switched off for shrink welding, or it can be raised subsequently for impulse welding. If a workpiece is to be provided with a sealing tape, Figs. 3, 4 (not shown), an additional plastics strip (32) is fed by a roller (33) and guide roller (34) into engagement with an open end of the workpiece. A U- or V-shaped folder (35) folds the strip over the open end and is welded to it. Subsequently the projecting parts of the strip are cut off by a stationary cutter 36 co-operating with rotating cutters 37, 38.</p> |
