GB603793A - A calculating device - Google Patents

Abstract

603,793. Calculating-apparatus. DIETRICHS, J. Aug. 28, 1945, Nos. 22103 and 22104. Convention dates, Aug. 16, 1944, and Aug. 9, 1945. [Class 106 (i)] A calculating device comprises one transparent and one opaque disc displaceable between two stationary transparent plates, the graduations on the displaceable transparent disc and the stationary transparent plate contiguous thereto being provided on the sides which face one another, the said plate and disc being spaced by the very small amount required to prevent surface friction. As shown, the transparent plates a, b are held by pins d. Rotatably mounted on the centre pin d are two discs e,f, the former being transparent and the latter opaque. The rotatable transparent disc e has graduations g, h, i on its upper face and the fixed transparent plate a has graduations g<11>, h<11> on its lower face, the disc and the plate being separated by an amount just sufficient to avoid surface friction. The opaque disc f has lines on both faces to enable it to be used with the disc e, plate a and also with the plate b which has graduations on its upper face. The discs e, f are rotated by wheels t projecting beyond the plates. In a modification, the discs and plates may be in the form of rules. The Specification as open to inspection under Sect. 91 comprises also a watch-shaped pocket calculator in which the discs are rotated by the manipulation of a winding knob through a shiftable pinion and spur gears. This subjectmatter does not appear in the Specification as accepted.