GB191510266A - Improvements in or relating to Motion-picture Apparatus. - Google Patents

Abstract

10,266. Evans, H. R. July 14. Kinematograph apparatus.-Relates to kinematograph film-stepping mechanisms of the beater type wherein the beater completes its movement under a yielding impulse and forces the film on to a mould, situated on the same side of the gate, in order to reduce wear and irregularity. The film is handled by an impact member, to which normal and additional movements are communi ated during contact with the film, preferally having provision for the access of air, and in one fom the beater is constituted by the direction of fluid under pressure upon the surface of the film. The film is held against the tension of the stepping movement by an intermittently-operating anchoring-device in the form of a mutilated roller. Fig. 1 shows a film A passing over feed-sprockets, B, B1, to a gate C and a hollow mould D with beater E of similar shape operated by such a cam F that the downward movement of the beater is concluded freely. Draw-off sprockets B2, B3 are provided. In other forms, the beater may be lifted by a cam against a restoring-spring, or may take the shape of a roller translated by a cam and link-work, and also caused to rotate so as to prevent rubbing between its surface and the film. In Figs. 5 and 6 is shown a modification wherein a pivoted spring nose J1 upon a rotating disk J strikes a cross-bar M1, thereby causing, through bent levers pivoted at L2, a gripping of the film A between feet M2 and others L4 carried by side arms L, to which the bent levers are pivoted. Levers, arms, and film then move on until the nose clears the bar, and subsequently continue freely under momentum until a stop P and spring L5 co-operate to release the grip and arrest the parts. Restoration is effected by an eccentric N and three-armed lever N1, N2, N3, and an anchor-pad (not shown) is intermittently and automatically applied to the film before it passes through the gate. In alternatives, the stop is effected by the tension of the film as it tautens, the restoring-lever N2 engages the cross-bar M1, thereby relaxing the grip, and there may be a yielding member through which the cam J1 operates the cross-bar. Further, the cam and cross bar may coact by roller parts producing a gradual beginning, or an air buffer may be arranged. A pneumatic beater is shown in Fig. 10, the film being led into a chamber Q past a slightly coned rotary plug valve R having a sleeve of oiled raw hide, and provided with ports cooperating with others in the casing S such that, as the valve is rotated, a puff of air issnes from a port T and carries the film downwards from proximity to the valve into the position shown in the Figure, thus stepping it, in part by the momentum of the air, which ultimately exhausts by a port Q1. Channeled metal blocks B4 between the members of the pairs of feed and draw-off sprockets limit the amonnt of slack that can be formed between them, and consequently the amount of hammering at the sprocket pins during stepping. In another arrangement, the film is fed by suction through a port which it ultimately uncovers, whereupon the inrush of air completes the movement. The guide-plates and mould present full surfaces to the film if curved, but if straight, they bear at the edges only ; forms of feed-rollers and other contact feeding members are described in which slots &c. prevent the occurrence of undesired air effects, such as suction : and in modified constructions of anchoring-devices, intermittently rotated cylinders have relatively high and low portions adapted to grip the film with the high parts. Specification 16,866/14 is referred to as describing apparatus much of which is identical with that disclosed in the present Specification, although differing in its functions.