| 摘要 |
1,241,249. Wrapping-machines. G. G. MAGNUSSON, and K. I. WEINER. 28 Aug., 1969 [17 Sept., 1968; 2 May, 1969], No. 42995/69. Heading B8C. A machine for wrapping pallet loads in shrinkable sheet comprises a gantry 8 having a conveyer 2 travelling therethrough, a device for feeding shrinkable sheeting from a supply roll 14 in the direction of the arrow 7 in a sliding manner along a guide arrangement arranged above the conveyer 2, a welding and severing device 22 consisting of two vertical welding jaws, one of which is provided with a vertically extending severing element, and a second conveyer 3 for conveying wrapped loads through a shrinking tunnel 42. The severing element cuts through the weld along the length of the weld. The guide arrangement may comprise a tunnel 9 having side walls 10 and a roof 11 which narrow in the direction of the arrow 7; the roof 11 being provided with an extension 12. In another embodiment, the guide arrangement comprises a central tube (50, Fig. 12) and two side tubes (51, Fig. 12), one side tube being arranged on either side of the central tube, extending in the direction of the arrow 7. Guide rods (55) extend downwardly from the side tubes (51). The side tubes (51) are closed at their free ends and are provided with nozzles (54), connected through the tubes (51) to a source of compressed air enabling jets of air to be directed obliquely and outwardly against the underside of the shrinkable sheeting. A vertically displaceable piston 46 or an air nozzle is provided for pressing the upper portion of the front end of the shrinkable sheeting covering the load to be wrapped down between the two side portions 20 of the shrinkable sheeting which are to be pressed against one another and welded together. Alternatively, the machine includes a lifting means (64, Fig. 12) for lifting the upper region of a non-tensioned portion of the shrinkable sheeting located between two successive pallet loads before the sheeting between said pallet loads is welded and severed. Such a lifting means comprises an isosceles triangle, the base of which is pivotally mounted in horizontal bearings arranged immediately prior (in the direction of conveyance 7) to the welding and severing device 22. The above-mentioned non- tensioned portion of the sheeting is produced by shifting the pallet load on the conveyer 3 backwards by a predetermined distance. Rods (66, Fig. 9) may be connected to the jaws of the welding and severing devices 22, extending parallel thereto. |
