Patent GB-917365-A (GB)
Title: Improvements in or relating to stereoscopic photography
IPC: F16M11/18
Filed: 1960-07-27
Abstract: 917,365. Stereoscopic mountings for cameras. MILLSPAUGH Ltd., and ANDERTON, F. W. July 21, 1961 [July 27, 1960], No. 26060/60. Class 98 (2). A stereoscopic mounting for a camera comprises a pivot-carrying member for fixing on a tripod with the pivot axis vertical, an arm mounted for swinging about the pivot, a camera support mounted for rotation relative to the arm about an axis parallel to the pivot, means for securing a camera immovably on the support, manually operable means for swinging the arm about the pivot, stop-means for limiting the swing of the arm to about 180 degrees, manually operable locking means for securing the arm in its extreme positions to the pivot, and gearing connecting the pivot-carrying member and the camera support so that a camera fixed to the support faces in the same general direction in both extreme positions of the arm. As shown, an arm 6. which is rotatably mounted by a bearing portion 7 on a journal 2 of a pivotcarrying member 1 adapted to be screwed on to a tripod spigot has a bearing 9 for rotatably mounting a support 10 to which a camera may be clamped by a rotatable free spigot 11 engaging in the camera tripod bush. The member 1 has integral with it a gear 14 which meshes with an identical gear 15 integral with the support 10 so the by swinging the arm 6 by means of the handle 180 degrees about the journal 2 the camera is displaced a distance twice the length between the two pivot axes and faces the same direction in the extreme positions. In order to permit different points of convergence other than infinity for the camera axes in the two extreme positions, as provided by the plug 23A, the housing 26 (of rigid unbreakable plastic) for the device carries plugs 23B, 23C having ends of different sizes which may, as desired, be screwed into the tapped hole 22 to serve as stops for shoulders 21A, 21B formed on the journal 2 of the member 1 to permit rotation of the arm 6 through different angles each a little greater than 180 degrees. Instead of the three plugs 23 and the two shoulders 21, there may be secured to the gear 14 a pair of pegs, one of which is adjustable against a convergence scale on the gear, co-operating with a fixed peg on the arm 6. Alternatively both pegs on the gear may be fixed and the peg on the arm may receive sleeves of different outside diameters applied through an aperture in the gear. The handle 17 may be screwed into the arm 6 to lock this to the journal 2. Alternatively the two gears may be of slightly different sizes, either being the larger, this resulting in the arm being rotatable through only one of the two arcs between the extreme positions since a final divergent direction between the camera lens axis and the bisector of the angle between the positions must be avoided. In further modifications an idler geer is disposed between the two gears on the member 1 and support 10. Such arrangements result in the provision of converging axes being impossible if the two gears are equal in size and in the impossibility of providing parallel axes if the two gears are unequal.