Patent GB-517505-A (GB)
Title: Improvements in or relating to film treating machines
IPC: G03C1/74
Filed: 1938-11-18
Abstract: 517,505. Drying long-length materials. KODAK, Ltd. Nov. 18, 1938, No. 33613. Convention date, Nov. 19, 1937. [Class 34 (i)] [Also in Groups IV and XIV] A machine for treating a strip of sheet material in which the strip is passed around a rotating drum which feeds it through the machine comprises means on the drum for supporting the margins of the strip and fluid pressure means for supporting the intermediate portion of the strip away from the surface of the drum. The drum may be, formed with a peripheral groove extending to within a short distance of the edges thereby providing peripheral flanges, and means' may be provided for introducing fluid pressure into the groove. Means may be provided for sealing the spaces between the strip and the drum at the points where the strip passes to and leaves the drum. The device may be used in machines for drying sheet material particularly those for removing residual solvent from freshly produced films. The tendency for films to become scratched or wrinkled or to pick up dust, is minimised. As shown in Fig 1, the curing section of a machine for forming a film base or support comprises a casing 15 in which a plurality of drying or curing drums 16 are rotatably mounted. The strip F is fed in a sinuous path over these drums. The casing is indented so as to ensure intimate contact between the air passing through the casing and the strip F. The surfaces 20 of the drums 16 are provided with shallow recesses 21 and marginal ridges 22 as shown in Fig. 6. A steady fluid pressure is maintained in the grooves 21 between the drum surfaces and the central portion 24 of the film strip. For closing the spaces subjected to the fluid pressure there are provided at each end of each drum, castings 28, 29, which are adjustable, and at the faces of each pair of drums as they approach and recede from each other there are provided tubes 34 as shown in Figs. 6 and 8. The ends of each tube 34 are carried on ball-bearings 35 mounted on stationary shaft 36. When the machine is started, a leader-stick attached to the film is passed around the various drums. To permit passage of this leader stick through the reservoir the tubes 34 and shaft 36 are cut away as shown at 38, and 37, and the exposed edges 40 of the cut away tube 34 have sealing strips 42 of felt. When the leader stick is to be passed through, the tubes 34 are turned on the shafts 36 to move the sealing strips out of engagement. They are automatically returned to sealing position by means of springs 48. The return movement may be limited by means of an adjustable stop. The opposite ends of each shaft 36 and the tubes 34 may be separately and independently adjusted so that these members may be moved backwards and forwards on the centre line 30, Fig. 5, between the drums to effectively seal the space between them. For this purpose each shaft 36 is mounted on a plug 64 mounted eccentrically in a larger plug 65. After the plugs have been adjusted they may be held by means of a set screw. Air under gentle pressure is supplied to the reservoirs between the drums through openings 70.