GB352294A - Improvements relating to cinematograph cameras - Google Patents

Abstract

352,294. Kinematograph cameras. ALLDRIDGE, R. S., 15, Wellington Road, Harrow, Middlesex. Aug. 9, 1930, No. 23923. [Class 97 (i).] In apparatus having a lens turret to enable lenses of different focal lengths to be rapidly interchanged, the camera front is provided with an aperture to receive the rear ends of the lens barrels or extensions thereof, and the barrels are mounted to slide axially in the turret so that any one of them can be pushed into the aperture when brought into register therewith. The turret consists of a disc 10 mounted on a boss 12 on the camera front 14 and carrying a number of lenses, of which only one is shown, the lens barrel 28 being slidable in a bush 30 fixed in a hole in the disc and having a rearward extension 32 fitting a hole 34 in the front 14. The barrel may be moved in or out of the hole by hand, but is preferably actuated by a nut 38 rotating freely on the bush 30 and engaging threaded projections 46 on the barrel, these projections being seated in slots 44 in the bush. The rearward movement of the barrel is limited by the engagement of a shoulder 48 thereon with an adjustable screwed-on ring 50. The lens assembly shown is of the kind described in Specifications 352,292 and 352,293, comprising two parallel objectives 54 for colour photography, and is provided with a septum 52, extending nearly to the shutter 56, for separating the two images on the film. With this arrangement the rear surface of the extension 32 is made flush with the rear edge of the septum, so that the turret cannot be rotated until the septum is withdrawn clear of the aperture 34.