GB271913A - Improvements in or relating to photographic film-packs and holders therefor - Google Patents

Abstract

271,913. Storr, B. V., and Ilford, Ltd. Dec. 2, 1925. Change-boxes, self-contained.- In a pack of the kind wherein the fllms are attached to pulling tabs, whereby they may be drawn one at a time from a front exposure compartment into a rear storage compartment round the end of a partition which serves as a film supporting frame, this frame is formed from a single piece of sheet metal bent into U-shape, Fig. 2, the rear limb 12 of the U being cut away near the bend to provide narrow resilient strips 15 which form the sole connection between the limbs, and together with pressed-up tongue 14 serve to press the front limb 10 against the films in the exposure compartment. The top of the limb 12 is bent at 16 to form a housing for two strips of velvet 17 forming the tight-trap. Flanges 11 are formed on the. front limb 10 to stiffen it, and flanges 13 on the rear limb 12 convert this into a tray for receiving the films. A tongue 18 is formed by notching, the top of the limb 10, and over this is slipped a loop of thread 22, Fig. 5, passing through the ends 20 of the film backing papers. When a film has been exposed, and its tab is pulled, the backing tears away from the thread 22 without disturbing the remaining films. The films and their supporting frame are mounted in a casing 7 closed at one end 9 by a cap, and having a slot at the other end through which the ends of the film tabs emerge. Casing and cap are preferably each formed by bending a single piece of sheet metal. To ensure protection against light passing between the casing and the cap, a black paper apron 24 is passed round the films, the apron extending from the edge of the exposure opening, round the bend of the U, and thence to the light trap 17 where it is folded is at 25 and slotted at the fold for the passage of the films. To facilitate threading of the film tabs through the light trap on assembling the pack, the outer tab is made longer than the remainder, round which it is folded as at 23<a>.