GB417841A - Calculating device - Google Patents

Abstract

417,841. Calculating-apparatus. WELLINGTON, B. R., 17, 1st Street, Troy, New York, U.S.A. May 28, 1934, No. 15853. [Class 106 (i).] A device for use in solving arithmetical, algebraic, and trigonometrical problems comprises a frame 1, Fig. 1, of triangular form with attachable scale bearing members 2, 3 arranged at right angles and jointed at the angle, a slide 20 adjustable along the scale member 3 carrying a protractor and a pivoted hypotenuse scale bar 25, and a diagonal scale member 34 slidable through undercut grooves at the corner of the scale members 2, 3 and provided with limbs 36, 37 at right angles for cooperation with lugs 18, 19 on slidable scales 14, 15 on the members 2, 3. The members 1, 2 and 3 are held together by spring clips 7, Fig. 3, and are formed with tongued and grooved edges and the slide 20 is formed to slide on a track formed in the frame 1 and member 2. The scales on the members 2, 3, and 25 are equal and uniform, while the scale on the diagonal member 34 represents the squares of the numbers of the scales 11, 12. Modified forms of the mounting of the members and of the slide are described. Examples of the use of the device are set forth in the Specification. A curved track 65 mounted on the member 1 and engaging a pin on a slide 40 on the bar 25 may be provided for use in solving quadratic equations.