GB1386365A - Calculator - Google Patents

Abstract

1386365 Calculating apparatus; transfer mechanism W KASNER 1 March 1972 9616/72 Headings G4B and G4D A calculator includes digit wheels 90a, 90b etc. (Fig. 9) and transfer wheels 92a, 92b etc. Each transfer wheel meshes with only the higher order wheel of its two associated digit wheels; to this end the teeth of wheels 92a, 90b, 92c, 90d etc. are in one plane and the teeth of wheels 90a, 92b, 90c, 92d etc. are in another plane. Pins 104 on each transfer wheel co-operate with a single long tooth 106 of only the lower order of the two digit wheels associated with the respective transfer wheel. Thus upon a complete rotation of, for example, digit wheel 90a, tooth 106a cooperates with a pin 104a to index transfer wheel 92a, and thus meshing digit wheel 90b, through one tenth of a revolution. A spring 70 locates the digit wheels in their adjusted positions. Levers 110a prevent overrun of the transfer wheels. Each digit wheel is formed with holes 91 engageable by a stylus (not shown) for number entry. The stylus is inserted through an arcuate slot 80 or 82 (Fig. 4), formed in respective opposite sides 30, 32 of the calculator casing, depending on whether addition or subtraction respectively is to be made. Fig. 4 shows the generally flat casing in opened-out condition, the sides 30, 32 (which are normally superposed) being connected by a hinge section 34. The arcuate slots are numbered as shown in Fig. 4, which also shows windows 84, 86 for viewing the numbers borne by the digit wheel teeth. The array of numbers relative to their associated arcuate slots is the same on both sides of the casing. The casing is formed with a tongue 36, which may be inserted in a pocket of a cheque-book wallet, Figs. 1 and 2 (not shown).