GB1274037A - Calculating machine - Google Patents

Abstract

1,274,037. Educational counter. SCHILDKROT SPIELWAREN G.m.b.H. 16 July, 1969 [17 July, 1968; 15 Oct., 1968], No. 35792/69. Headings G4D and G5G. An educational device includes a multistage counter, a selector dial for entering numbers into the counter and a set of endless belts coupled to respective stages of the counter and passing below windows in the casing of the device. The belts carry digital symbols whereby a number entered in the counter is represented pictorially by the symbols displayed in the window. The device consists of a dial 3 driving a wheel 19 through bevel gears. The wheel 19 has a ring 20a carrying the numerals 0-9, 0-9 visible through a window 6 and a knurled end 20 projecting through the casing 1. In addition, the wheel 19 drives an endless belt 23 through co-operating pins and apertures 22. The belt carries two lines of unit symbols 27, 28 visible through a window 4. A shutter 29 movable laterally by a pivoted lever under the control of a cam surface on the wheel 9, covers each line of symbols 27, 28 in turn and is moved as the wheel passes between 9 and 0. A second wheel 39 driven by a transfer-mechanism as the wheel 19 moves between 9 and 0, has a ring 40 bearing numerals visible through a window 7 and drives an endless belt 44 having one line of tens symbols 46. The transfer-mechanism comprises two diametrically spaced, spring-loaded pins projecting from the wheel 19 which are moved radially inwardly by a fixed cam to engage a gear fast with wheel 39 and move it step-bystep. A disc 2 beneath the dial 3 bears two sets of numerals 1-10 and is movable to display one or other set through finger holes in the dial under the control of lever 9 setting the calculator for addition or subtraction. A finger stop 10 is displaced to position 11 or 12 against a spring on entering a numeral. In use, a series or numbers to be added or subtracted are entered by dial 3 (or by knurled wheels 20, 41) and the answer displayed numerically in windows 6, 7 and graphically as a series of unit and tens symbols in windows 4 and 5. The calculator includes a paper roll visible through can opening for recording a question- and-answer. A transparent cover is movable to .cover-the paper roll and is interconnected with a shutter movable to close windows 6, 7, Fig. 7 (not shown). Alternatively, the calculator carries a slate and a shutter movable by a hand grip to cover the windows 6, 7. The calculator shown in Fig. 8 may be used for multiplication and division by repeated addition and subtraction. The finger stop is fixed to a member 67 coupled to a pivoted lever 69 by a link 68. The lever 69 carries a pawl 73 stepping a counter 77 on each actuation of the dial. A lever 79 is pivoted counter-clockwise for addition or subtraction to move the pawl 73 clear of the counter.