GB1159805A - Calculator. - Google Patents

Abstract

1,159,805. Calculators. S. & V. KAYE Ltd. 26 Oct., 1966 [28 Oct., 1965], No. 45781/65. Heading G4B. A calculator for comparing the values of parameters given in fractional form, comprises three relatively movable members bearing logarithmic scales, first and third members bearing scales which are graduated on the same absolute scale to represent the numerators of the fractional forms to be compared, and a second member bearing a scale which is graduated to represent the denominators and being located in relation to the first and third members in such a position as to enable the scales carried by the first and third members to be set against the scale carried by the second member, index marks on the first and third members showing when the scales carried thereby are identically located with respect to the scale or the second member, the index marks having associated marks to indicate which of the scales carried by the first and third members is further advanced with respect to the scale carried by the second member. As illustrated, the calculator comprises three discs 1-3, the scales on the discs 1 and 3 representing pence and shillings, and the scale on the disc 2 representing weight. The scales or discs 1 and 3 are coloured red and green respectively, and the adjacent parts of the scale on the disc 2 are coloured correspondingly. The disc 2 is transparent or has a transparent annular portion such that indicia carried by the disc 1 can be viewed through a window 5. A pair of arrows 6 when adjacent line 7 or the disc 1 indicate identical values of two articles being compared, and when adjacent " RED or " GREEN" indicates that the article represented by the red or green scale is the better value. The members may be rectilinear.