Patent GB-317057-A (GB)
Title: Improvements in or relating to calculating or the like machines
IPC: G06C21/04
Filed: 1929-08-08
Abstract: 317,057. Burroughs Adding Machine Co., (Assignees of Pasinski, W. J.). Aug. 9, 1928, [Convention date]. Adding and subtracting apparatus; error-check. ing arrangements.-A machine particularly for dealing with bank accounts is provided with means for proving the accuracy of the work done by the operator. According to the invention a mechanism is set by the amount keys when an item is entered in a given columnar position of the paper carriage. In the form shown as applied to a Burroughs machine, the item representing the " old balance " is entered in a pick up column and the carriage is then tabulated to the " withdrawal " and " deposit " columns to receive and print the desired entries. When the carriage is moved to these positions the set mechanism is moved to an inoperative position where it remains until a later predetermined column called " proof " position is reached, whereupon it is moved to a positon to co-operate with the amount keys, the machine being prevented from effective operation unless the same amount keys are depressed in the " proof " column as were depressed in the " pick up " column. The mechanism is also adapted to be controlled by the subtraction control lever so that the second entry of the " old balance, " must be of the same sign as the first entry. The amount keys 291, Fig. 1, co-operate with the usual detent plates 214 to hold the keys depressed, the plates being held by latches 228 until near the end of an operation, whereupon they are released to free the keys by the usual bail 202. The stem of each amount key is provided with a slot 20 for co-operation with a pin 21, Figs. 2 and 3, of a detent 22 pivoted on a pin 23 extending from a slide 24, the detent being maintained in one or other of two positions, Figs. 3 and 5, by an overcentre spring 26. The slides 24 are connected to a rod 52 and are normally held in the position shown in Fig. 6 with the pins 21 free from the slots 20. When the paper carriage is moved to the " pick up " column a roller 40, Fig. 1, thereon, rocks a yoke member 42 and, through an arm 43 and lever 44, pulls down a link 45 so as to rock a bell-crank lever 50 carrying the rod 52 and thereby move the slides 24 rearwardly to position the pins 21 in the slots 20. When an item has been entered in this column the corresponding detents 22 are moved to the position shown in Fig. 5 and the machine is operated. As the paper carriage moves to the next position the roller 40 frees the yoke member 42 and the spring 47 moves the slides 24 forward, the detents being maintained in set position as the pins 21 are freed prior to the release of the keys as shown in Fig. 9. To ensure that the slides 24 shall be moved in a positive manner before the release of the amount keys the release bell crank 630, Fig. 12, carries a pass-by pawl 623 which, in addition to co-operating with the roller 232 on the lever 219 carrying the bail 202, actuates an arm 54, pivoted on the shaft 51 and connected at its upper end to the rod 52, through contact of a roller 55 with a cam surface on the pawl 623. When the paper carriage is tabulated to the " proof " column another roller on the carriage slightly smaller than the roller 40 moves the slides 24 rearwardly to a position where the pins 21 are just short of the forward edge of the key stems. The " old balance " is again entered on the key board and if the amount agrees with the original entry the slots 20 on the keys will be opposite the respective pins 21. If an error has been made one or other of the slides will be blocked by a key stem as a result of which the operation of the machine is prevented. On the shaft 51 is pivoted a lever 83, Fig. 14, connected at its upper end to the rod. 52 and provided with a stud 82 normally working in the horizontal part of a T-shaped slot in a link 70. The link 70 is connected at its forward end, by a spring 68, to a lever 66 having an arm 76 with a roller 75 co-operating with a cam surface 74 on the link and a pin 73 engaging the bifurcated end of the link 70. In normal operation the motor starting bar 60 on depression rocks a lever 61 and through a roller 64 thereon rocks the lever 66 and tensions a spring 62 to raise the usual link 63 to start the motor operation. Movement of the lever 66 pulls the link 70 forwardly to cause the abutment 71 thereon to pass across the path of a stud 72 on the link 63. With the paper carriage in the " proof " position the stud 82 is directly over the vertical branch of the T-shaped slot so that when the starting bar is depressed and the link 70 moved, the pin 82 moves to the lower part of the slot and thus locks the link to the lever 33. If an error has been made the lever 83 through its connection with the rod 52 and slides 24 is held against movement so that the link 70 cannot move forward and the abutment 71 being presented to the stud 72 prevents the link 63 rising to a position to start the motor. Accidental engagement of the stud 82 with the vertical branch of the slot is prevented by a hooked-shaped projection 86 on the link 70 co-operating with a locking bar 84. The control mechanism associated with the subtraction lever 10, Figs. 1 and 19, comprises a slide 90 connected to the rod 52 and provided with a spring controlled detent 91 having a pin 95 cooperating with a notch 96 in an arm 97 having a cam slot 98 in which the subtraction lever operates. In the " pick up " position the slide 90 moves rearwardly with the slides 24 and the pin 95 enters the notch 96 and the detent 91 is set in accordance with the movement of the subtraction lever. In the " proof " position, if the subtraction lever is not moved to its original position the pin 95 is arrested by the arm 97 and prevents full rearward movement of the slide 90 and consequently of the rod 52 and lever 83. The detent 91 is restored to normal position by its contact with a pin 99. The mechanism mav be released in several ways depending upon the error involved. If the error has been made in the " proof " column the column release; keys R, Fig. 1, may be utilized to restore the amount keys or the general error key E, Fig. 23, may be used which on partial depression releases the amount keys and on full depression releases both the amount keys and the slides 24. The error key E is carried by a bell-crank lever 100 having a link 101 co-operating with a stud 103 on the arm 219 of the release bail 202 and provided with a depending extension 104 having a pin 105 adapted to co-operate with a pass-by pawl 106 pivoted to an arm 108 loose on the shaft 51 and connected to the rod 52. The pawl 106 has a nose 109 engaging a pin 110 on a stationary arm 111 and by reason of the movement of the rod 52 when the carriage moves to the proof position the pawl is moved into the path of the pin 105 so that when the error key is fully depressed the rod 52 is rocked. The error key may be depressed in any other position of the carriage as the pawl 106 is out of the path of movement of the pin 105. To restore the detents 22 at the end of an operation in the " proof " position, the release bell crank 630, Fig. 13, rocxs the shaft 121 and through an arm 120 thereon co-operating with a pin 122 on a projection of the link 70 rocks the arm 83 sufficiently to cause the slides 24 to move until the slotted keyboard plate 33, Figs. 2 and 3, cams the detents back to normal. U.S.A. Specification 1,580,534 is referred to.