| 摘要 |
<p>1,192,981. Packaging. WELDOTRON CORP. 14 June, 1967 [3 March, 1967], No. 27409/67. Heading B8C. [Also in Division B5] In packaging articles between opposed sheets, electrostatic force is used to force the sheets, one of which may be heated, into contact about the articles, the force being created by passing the sheets between electrodes, one of which is shaped to locally ionize the atmosphere and produce a charge on the adjacent sheet. The electrodes shown consist of a flat plate opposing an oppositely charged series of points mounted on a plate or a grid of tubes. Electrostatic force is also used to guide sheets in web form to the packaging position. In one form, a radiant heater 16 heats a sheet 24 held in a frame 26, the heat radiating between tubes from which extend ionizing points 30. A card 22 bearing articles 20 to be packaged, rests on a charged plate 10. The frame descends and the electrostatic charge causes the sheet 24 to embrace the articles and adhere to the card. The sheet or card may be adhesive coated or otherwise rendered adhesive. In a continuously operating apparatus, Fig. 3 (not shown), cards with articles on them are advanced by a conveyer to a position where a cover web is laid upon them. The cover web descends between radiant heaters and then between a pair of electrodes which produce a guiding charge as the web turns to lay along the cards. The conveyer carries the assembly between electrodes similar to those of Fig. 1, arranged above and below the upper run. The cards may be replaced by a continuous web. In another embodiment, a continuous web of card 102 having article receiving perforations, is laminated with a bottom web, passing between heaters 116, 118 and guiding electrodes 120, 122, by further electrodes 126, 128. A cover web 134 is applied as in the last described arrangement, after articles have been placed in the perforations. In a further device, Fig. 6 (not shown), electrodes cause a heated web to conform to hollow moulds forming a conveyer chain, the recesses so formed being filled and a cover web applied as before.</p> |
