Patent GB-474501-A (GB)
Title: Improvements in computing devices
IPC: G01G23/22
Filed: 1936-11-28
Abstract: 474,501. Weighing and other measuring apparatus; specific gravity estimating- apparatus. TOLEDO SCALE MANUFACTURING CO. Nov. 28, 1936, Nos. 32665 and 32666. Convention dates, Nov. 29, 1935 and Oct. 16, 1936. [Class 143] [Also in Groups XIX and XX] In a logarithmic computing device the automatic load-balancing mechanism of a weighing scale or other measuring mechanism is connected to a movable member carrying a logarithmic or modified logarithmic curve to cause the member to move so that the curve moves logarithmically along a row of logarithmicallv arranged indicia on another member which is manually shiftable longitudinally of its row of indecia to correspond with a selected datum. As shown in connection with a weighing scale employing an indicating cylinder 12, Fig. 1, automatically rotated in proportion to the load placed on the scale pan, the indicating cylinder is marked with a logarithmic curve 13. A ribbon 22 is stretched immediately in front of the cylinder from a spring drum 20 to a hand-operated drum 31. The ribbon is divided logarithmically and the divisions are numbered with the antilogarithms. With the ribbon adjusted so that the unit graduation coincides with a fixed pointer 34, a one-lb. weight on the scale pan causes the curve 13 to intersect the graduated edge of the ribbon at its unit graduation. Other loads placed on the scale pan will then be correctly indicated on the ribbon at the intersecting points of the curve and ribbon. Similarly by other appropriate settings of the ribbon, the weight may be indicated in other standards of weight, or in pints or other units of volume, or indicate the yards in a bolt of cloth. The specific gravity of a liquid may be determined by placing on the scale platform two vessels containing the liquid and water respectively and counterbalancing these by means of a tare poise. A solid is now suspended in the water and the ribbon 22 is adjusted until its unit graduation is intersected by the curve 13. The same solid is suspended in the liquid to be tested, and the specific gravity of the liquid is then indicated by the new point of intersection of the curve and ribbon. The specific gravity of a solid may be ascertained by suspending it in a counterbalanced vessel of water on the platform, adjusting the ribbon until its unit graduation intersects the curve, and then lowering the solid to rest on the bottom of the vessel when the new intersection will indicate the specific gravity. Identical pieces, such as screws, may be counted by placing a small number on the platform, adjusting the ribbon until the same number thereon intersects the curve, and then adding the remaining pieces when the number thereof will be directly indicated on the ribbon at the new intersection. The percentage of the original weight of an article remaining after processing may be ascertained by weighing the article before and after processing, and by making suitable adjustments of the ribbon. A quantity of material on the platform may be divided into any desired number of parts by setting this number on the ribbon to intersect the curve and afterwards removing material so as to bring the point of intersection to the successive graduations. A lamp inside the casing illuminates the graduations and a slidable lens 40 magnifies the indications. In a modified apparatus, the pointer 34 may be adjusted along the viewing opening adjacent to a stationary graduated strip, Fig. X (not shown), to allow values having more than two factors to be indicated, for example, the money value of a quantity of screws at a predetermined price per gross. As applied to the " fan " type of weighing scale, Fig. XI, a modified logarithmic curve 66 is inscribed on the pointer 65, and the logarithmic ribbon 68 is arranged obliquely, the intersecting points of the curve and ribbon being observed through an elongated viewing window 74. Specification 237,437, [Class 143], is referred to.