Patent GB-459138-A (GB)
Title: Improvements in or relating to cinematographic apparatus, more especially to those with a continuous reeling off of the film
IPC: G03B41/08
Filed: 1935-06-28
Abstract: 459,138. Kinematograph apparatus. PARAIN, P., 11, Rue du Bois de Boulogne, Paris. June 28, 1935, No. 18629. Convention date, June 28, 1934. [Class 97 (i)] In reversible apparatus for projecting from one film length while another is being re-wound, the film lengths are fed continuously over independent courses, and a rotary optical compensating system having a plurality of objectives is provided: film - operated means for controlling the driving motor, light source, &c., may be provided. Figs. 1 and 2 show two films 6<1>, 6<2> driven simultaneously in opposite directions between spools 7, 8 by sprockets 16. Separate light sources 1<1>, 1<2> condensers 3<1>, 3<2>, and reflectors 13<1>, 13<2> direct projection beams through objectives 10<1>, carried by a rotary drum 9 on to a reflector 11 alternatively directing the beams to the screen. The reflector 11 is movable so as to change the operative beam when the directions of the film runs are reversed. The sprockets are driven by a motor 15 through worm gearing 18, shaft 17, and bevel wheels 16<1>, 181, and the drum 9 is rotated from the shaft 17 by gearing 14. The spools may be driven by belts &c. or may each Be directly driven by a separate low-speed induction, motor. Brake bands 21, controlled by the film tension through rollers 19 on bell-crank levers 20, may be provided for each spool. The driving mechanism may be such that the films are simultaneously driven in the same direction, one film being looped so as to pass through its gate in a direction opposite to that of the other film. The films may be slotted, notched, or provided with projections, to operate switch means for reversing the motor circuit, breaking the light circuit &c. or such switches may be controlled by the quantity of film on a spool. If the film is slotted, it may allow rollers on' each side of the film to engage to complete a circuit, or may, as shown in Fig. 10, slide over a fixed drum 36 to permit a member 37, linked to a lever 38, to be raised by a spring 40 so that a pin 41 on the lever may operate a switch ; the pin 41 may, alternatively, operate through mechanism. Fig. 6 shows a spool core enclosing contacts 25 held in engagement by a push button 24. When the film is about to run off the spool, a spring 26 raises the button and separates the contacts. A lever riding on the film roll may close a circuit when the diameter of the film roll is large, or a slidable member 32, Fig. 9, engaging the film on both pay-out and take-up spools 7, 8, respectively, may have projections 34 tilting a lever carrying a mercury switch 35. The Specification as open to inspection under Sect. 91 comprises also a continuousfeed projector, for a single film, having a cylindrical gate passage 4, Fig. 1 (Cancelled), and a rotating lens drum 9, surrounded by a rotating diaphragm member 9<1>. The axes of the drums and of the cylindrical gate passage may be coincident, and the distance from the film to the lenses may be equal to the focal length of the lenses, a prism 11 and a focusing lens being also provided. Such a projector may be adapted for simultaneous projection from two or more films by the provision of duplicate parts arranged round a common central light source 1. Alternatively, two light sources 1 &c. and one lens drum 9, may be provided, as shown in Fig. 3 (Cancelled), separate or combined mirrors or prisms 11 being also provided. A two-rank film for use in a projector having a mask to cover the image rank not being projected is also described. This subject-matter does not appear in the Specification as accepted.