| 摘要 |
1495038 Repairing damaged film perforations J S STANFIELD and P W TRESTER 22 Oct 1975 [29 Nov 1974] 43269/75 Heading G2E Film-strip having damaged or missing sprocket holes along one edge is repaired by attaching a reinforcing strip having corresponding sprocket holes. The film 22, whose sprocket feed perforations 24 may have been damaged or even torn away altogether, as seen in Fig. 2, passes from a supply spool 26 into the repair section of the apparatus, which is mounted on a support frame 44. The repair strip 34 is provided in the form of a roll of tape 32, already prepared with perforations which correspond with the perforations in the film-strip, and having a pressure sensitive adhesive on one side. The film is wound off spool 26, and passes between a pair of rollers 50, 52, the lower of which is heated, so as to smooth and straighten out the film. It then passes over guide rollers 70, 71 to the actual repair station which comprises two rollers 56, 58, between which the film and tape are passed in contact. The lower roller 58 has a smooth metal surface with sprocket teeth 60 round its periphery (seen more clearly in Fig. 4 (not shown)). The upper roller 56 carries a resilient rubber sleeve 74, having a series of apertures (114) (Fig. 4) which correspond with the sprocket teeth 60 (see also Fig. 7 (not shown)). As the film and repair tape are brought into contact between rollers 56, 58, they are initially aligned by a sprocket tooth passing through a sprocket hole in each. They are then laminated together as they are wound on by means of a handle, and are passed between a further pair of rollers 64, 66, which apply further heat and pressure. The film is finally wound on to a take-up reel 38. Thus the sprocket holes in the tape form reinforcement or replacement holes for those in the film. |
