GB1391021A - Photographic apparatus - Google Patents

Abstract

1391021 Self-processing film apparatus POLAROID CORP 19 April 1973 [24 April 1972] 19006/73 Headings G2A and G2X A container for film units which are sequentially exposed and treated with a processing liquid has means for influencing the flow of the liquid so as to obtain a more uniform distribution. Fig. 1, shows a film container 12 of known type housing a plurality of self-developing film units, which are exposed one by one through an aperture 26 and then withdrawn through a slot 40, from where they pass between a pair of rollers (72, 74), Fig. 3 (not shown). These rupture a pod of processing liquid which is then squeezed between the two sheets of the film unit. The liquid tends to advance in the form of a bow-shaped wave, as shown in Fig. 5, which can result in uneven distribution of the liquid, and hence uneven development. To counteract this tendency, the forward wall 22 of the container 12 has a number of projections 78a, 78b, 78c moulded integrally therewith, tapering towards the rear. These exert an additional pressure on the liquid which has a retarding effect on the flow in the centre of the wave front, so that its shape is more as shown in Fig. 6. A similar effect may be obtained by forming recesses at the sides of wall 22 (e.g. 80), Fig. 7 (not shown) or (300), Fig. 9 (not shown). The container is intended for use in a folding single lens reflex camera, Fig. 4 (not shown). Since the walls of container 12 are normally formed of a thin plastics material, they are likely to be flexible, and therefore the position of the projections 78a, 78b, 78c may vary. In order to prevent this, the parts of the camera which surround and engage the container are such as to hold it firmly and prevent such flexing.