Patent GB-713484-A (GB)
Abstract: 713,484. Calculating-apparatus. BELL PUNCH CO., Ltd. Feb. 19, 1952, No. 4415/52. Class 106 (1) A multi-bank key-set calculating machine comprises two portions, each totalizer wheel of one portion having associated with each number thereon a numeral which is the remainder obtained when the numeral represented by the corresponding number (allowing for the order of the totalizer wheel or that numeral multiplied by a specific factor is divided by a selected prime number equal to or greater than eleven or a multiple of such a number, and each totalizer wheel of the other portion having associated with each number a numeral which is the difference between the numeral represented by the corresponding number and the selected prime number or said multiple or the next higher multiple thereof. The additional numbers are used, as described in the Specification, in the checking of calculations effected by the machine. In the machine described, the said prime number is 13 and when the invention is applied to a machine for dealing with Sterling currency, the specific factor referred to above is 960, the number of farthings in one pound. When a key 25 is depressed, a shoulder 26 in the key stem engages a key bar 27 pivoted to a lever 35 and connected by a link 30 to a lever 37. A stop bar 43 also connected to the levers 35, 37 is thus moved forwardly until the appropriate abutment engages the operated key stem. During this movement, an actuator rack 67 is raised through links 73, 74 and 75 connected to the lever 37. Finally, the depressed key stem engages a corresponding lug 79 on a bar 78 pivoted about a longitudinal axis and the bar is rocked to move a lug 83 carried thereby in a slot 82 formed in a lever 71 to which the rack 67 is pivoted. A spring 85 is thus able to rock the lever 71 clockwise to engage the rack 67 with its totalizer pinion 68. When the key is released, the parts are restored by the spring 85, the totalizer wheel being operated by an amount depending on the key which was depressed. The lever 71 is finally restored to disengage the rack 67 from the totalizer pinion, the pinion having been suitably decelerated by the arrangement of the links 73, 74, 75. If a key is incompletely depressed, the bar 78 is not rocked and a pawl 49 normally held downwardly by a lug 81 on the bar is free to engage the under-side of the stop bar 43. When the key is released, the pawl 49 engages an abutment 48 on the stop bar and is moved rearwardly, rocking an arm 51 on which it is pivoted clockwise so that a tail 53 of the arm rocks a bail 54, extending across the machine, against a stop 90. The stop bar 43 and connected parts are thus held in a partially operated position and a corresponding projection 42 of a hook 40 on the key bar 27 is located in a hole in the key stem to prevent restoration of the mal-operated key. Depression of any other key in the order is prevented since the shoulder 26 of the key will engage the corresponding projection 42 and will block movement of the hook 40. When the bail 54 is rocked clockwise, a lever 59 is able to rock counter-clockwise and its bent end moves behind the pin 44 coupling the stop bar 43 and the lever 35. Levers 59 in the other orders are also rocked, their bent ends moving in front of the pins 44 to prevent rocking of the levers 35 and consequently depression of any keys in these orders. The mal-operated key is then operated correctly, after which the corresponding stop bar 43 returns until the pin 44 abuts the end of its lever 59 when the totalizer pinion remains engaged with the rack 67. Since a non-return pawl prevents reverse rotation of the pinion, the key that was mal-operated is now locked also. A key 64c is then operated to rock a bail 63 so as to restore the levers 59 and unlock the machine. If other keys are depressed simultaneously with a key which is not fully depressed, all the operated keys are held in a partially depressed position. However, operation of the bail 63 allows all but 'the mal-operated key to be restored whereupon the latter may be properly operated and the bail 63 again rocked to unlock the machine. The transfer mechanism between any two adjacent orders may be rendered inoperative by depression of a corresponding button 100 which operates a member 101 to move the transfer wheel along its axis out of engagement with the transfer pin of the lower order. In order to enable the machine to be separated into the two portions referred to above for checking purposes, one of the buttons 100 has a groove 107 to receive a locking catch 108.