Patent GB-317090-A (GB)
Title: Improvements in or relating to calculating or accounting machines
IPC: G06C21/04
Filed: 1929-08-09
Abstract: 317,090. Burroughs Adding Machine Co., (Assignees of Muller, R. L.). Aug. 10, 1928, [Convention date]. .4dding and subtracting apparatus; error-checking arrangements.-In a machine particularly for use in commercial posting work a mechanism is provided for proving the accuracy of the work done by the operator. The check is usually made on the entry of the customer's " old balance," and according to the invention the entry of this item in a predetermined (pick-up) column sets a check or proving mechanism which is adapted to be conditioned automatically prior to a predetermined subsequent operation (proof position), during which the item is again entered to prevent depression of any amount keys other than those that were depressed when the item was first entered. As shown applied to a Burroughs machine, Fig. 1, each bank of keys is provided' with a pair of sliding members 20, 40, Fig. 2, mounted on shafts 21, 22 and each key is provided with a detent 217 having a pin 26 for engaging the nose of a dog 28 that is pivotally and slidably mounted on a shaft 21. Each dog has a tail piece with projecting portions 30, 21 that normally lie above and project through a slot 32 in the slide 20 respectively. The slide 40 is provided with a projection 41 carrying a stud 42 engaging an arm 43 on the shaft 22 and has another projection 44 for engaging the slide 20. The slide 40 also carries a series of pins 45 engaging notches in the tails 46 of the dogs 28. With the paper carriage in the '' pick up " position the item (old balance) is entered by depression of the amount keys, the appropriate dogs 28 in each bank being depressed to move the slides 20 rearwardly. Movement of the slides 20 removes the locking projections 25 thereon out of the path of movement of arm 52 of locking members 51 loosely mounted on a shaft 50. Each locking member is provided with an extension 53 cooperating with a spring-controlled bail 54 adapted to control the motor driving connections. The connection between the shaft 50 and a pair of adjacent locking members is shown in Fig. 3 and comprises a collar 60 fixed to the shaft and connected by springs 58, 58a to ears 57, 57a on the members 51, 51a and provided with lateral lugs 61, 62 extending over the arms of the members. On the movement of the paper carriage to the " pick up " column a roller 74, Fig. 14, on the carriage operates an arm 73 and yoke member 72, Fig. 1, to rock a lever 70, Figs. 1 and 10, a stud 75 on which engages a pass-by pawl 76 on a swinging member 77 to cause the projection 85 thereon to be set into the path of a pin 87 on an arm 88 fixed to the rock shaft 600. The member 77 is pivotally attached to one arm of a bellcrank 81, 82 so that when the shaft 600 is rocked during the operation the bell-crank 81, 82 is rocked and through the connection of the arm 81 with a bell-crank 93, 94 raises the arm 93 thereof to engage the pins 98, 100 of arms 99, 101 and rock the shafts 50, 22, the parts being latched in position by a spring-controlled latch member 91 co-operating with the arm 82. Movement of the shaft 22 through the connection 42, 43 displaces the slide 40 rearwardly whereby the studs 45 withdraw the projecting noses of the dogs 28 out of the path of the studs 26 on the detents 217. The dogs 28 however that have been tilted by depression of a key are not moved rearwardly as the pin 45 is free to. move under the tail end 46 of the dog. Movement of the slides 40 in banks where no key is depressed carry the slides 20 rearwardly with them. Counterclockwise movement of the shaft 50, Fig. 2, tends to rock the members 51. In banks where a key has been depressed the arms 52 pass by the locking projections 25 of the slides 20 and towards the end of an operation when the keys are released the slides 20 move forward slightly, being blocked against further movement by the arms 52 as in Fig. 6, the keys in these banks being free of the dogs 28. In those banks where no key is depressed the slides 20 being moved by the slides 40 permit the arms 52 to be moved yieldingly into engagement with the bottom of the projections 25 in such a manner that the shoulders 56 of the arms 52 as shown in Fig. 8 engage the projections 25 and block the return movement of the slides 20 so as to hold the dogs inoperative. The machine is free to be operated in the normal manner in the " charges " and " credits " columns. As the paper carriage moves to the " proof " column a roller 107 thereon slightly larger than the roller 74 rocks the lever 70 and a pin 105, Fig. 10, thereby releases the latch 91 and frees the bell-crank levers 81, 93 so that the shafts 22, 50 are free to rock back to normal. Movement of the shaft 22 carries the slide 40 forward and places the dogs again under the pins 26 on the detents 217. The shaft 50 however cannot return because of the engagement of the arms 52 with the locking projections 25 and the slides, being maintained in rearward position, prevent the undepressed dogs being rocked as the slots 32 in the slides 20 do not clear the forward noses 30 of the dog so that the only keys that can be depressed are those that were previously depressed in the " pick up " column. Also, unless all these keys are depressed, the arms 52 are not freed and the bail 54 cannot move forward. If there is no old balance to enter this is checked in the " proof " column by depression of a special key 150, Fig. 13, a stud 152 on the detent 217 of which raises a link 154 to cam the shoulder 155 over the edge of a fixed slotted plate 156 and remove the curved rearward end 158 from the path of movement of the bail 54. This link 154 is freed during the normal operation by the end of the usual detent plates 214 engaging a shaft 160 carrying an arm 161 having a cam surface engaging a lug 163 on the link 154 to free the shoulder and thus prevent the link interfering with the bail 54. In order that the operator may enter an item on the amount keys for work in the " proof " column while the carriage is tabulating to the column, the arm 73 operating the lever 70 is maintained in operated position by a latch 191, Fig. 14, until a roller 200 on the carriage by engagement with a tripping pawl 197 releases the latch 191 and frees the lever 70. The Specification as open to inspection under Sect. 91 (3) (a) comprises also means whereby when the last of the amount keys is depressed the machine is set in operation automatically without requiring manipulation of the usual motor starting bar as described in Specification 343,060, [Class XIX]. Means are also described for controlling the check mechanism by means of the subtraction lever to ensure that the first and second entries are of the same sign as described in Specification 343,061, [Class XIX]. This subject-matter does not appear in the Specification as accepted.