GB1355655A - Method and apparatus for continuously wrapping flexible sheets - Google Patents

Abstract

1355655 Apparatus for continuously wrapping flexible sheets AGFA-GEVAERT 5 July 1971 [26 Aug 1970] 41126/70 Heading B8C In a method of continuously wrapping flexible sheets, e.g. radiographic sheets, webs 16, 11 of identical wrapping material are advanced by pairs of draw-rollers 25, through the apparatus which comprises glue applicators 22, 24 and 28, 29 respectively for gluing the underside margins of the web 16 and transverse strips of adhesive on the web 11 spaced to be located between successive sheets of radiographic film 33 which, with associated carboard sheets 34, are subsequently deposited on the moving web 11 by a feed mechanism; folding members 30, 31 which fold the lateral margins of the web 11 over those of the web 16, and a device 32 for removing the tension from the folds of the web 11. Rotatable cutters 26, 27 sever the webs at the centres of the bonds at the transverse adhesive strips. Tear strips 57, 58 are fed from rolls 55, 56 and under a roller 20 to lie inside the folds at the sides of the webs 16, 11. The tension relieving- device 32, Fig. 2, comprises a pair of arms 43, 44 which are pivoted respectively at 41, 42 to a fixed support 40, urged towards each other by a spring 49, and carry upstanding arms 45, 46 respectively at their outer ends. The arms 45, 46, having rounded opposed edges, project through curved slots in a pair of fixed, parallel plates 47, 48 which straddle the webs 11, 16 and are spaced apart by a distance slightly greater than the thickness of a wrapping at the folds. The pressure applied by the arms 45, 46 and the counter pressure applied by the plates 47, 48 deforms the folded edges of web 11 to sharply bend through upper and lower corners 50, 51, Fig. 4, and provide a permanent set. The movable pressure members 45, 46 may be mounted close to, or into, the folding members 30, 31. In a modification, Fig. 6, not shown, the rigid pressure members 45, 46 are replaced by small rollers (62) fitted to the outer ends of the arms 43, 44, the rollers having bevelled edge portions (62, 63). The pair of plates 47, 48 may be omitted in which case pairs of upper and lower rollers (65, 66) may be provided near the folded edges of the wrapping. In an alternative arrangement the axes of a pair of rollers at one side of the packing do not coincide with the axes of the corresponding pair of rollers at the opposite side of the wrapping.