Patent GB-636967-A (GB)
Title: Improvements in and relating to record card controlled accounting machines
Filed: 1947-09-10
Abstract: 636,967. Statistical apparatus. BRITISH TABULATING MACHINE CO., Ltd. (International Business Machines Corporation). Sept. 10, 1947, No. 24867. [Class 106 (i)] A record card controlled accounting machine includes a record card in which digits not exceeding 11 are each represented by not more than four records in different index positions in a card column, a record in one position representing 5 for decimal notation (or 6 for duodecimal notation), and records in other positions representing lesser valves, an accumulator having a first and second adding wheel for each denomination, the second wheel having positions in two successive steps representing 0 and 5 (or 6), and the first wheel having a plurality of successive steps representing 0, 1, 2, 3, 4 for decimal notation (or 1, 2, 3, 4, 5 for duodecimal notation), carry means operative after the first wheel has passed to 0 to move the second wheel one step and carry means from the second wheel to the first wheel of the next higher denomination, and sensing means adapted, on sensing one or more index positions representing a value less than 5 (or less than 6 in the case of duodecimal notation) to enter that value into the first wheel of the related denomination and, on sensing an index position representing a value 5 (or 6), to enter this value into the second wheel. Fig. 5a shows a card with numbers 1 ... 9 represented in a four-position code 2, 1, 5, 2. The sensing of a hole in the first or second position completes a circuit from line 59 through card lever contacts 60, roller 61, brush 12, plug connection 55, contact R1a, Fig. 5b, contact Aa (now closed) and R8a, Sa, R10b, to energize relay AM. Energization of relay AM, Fig. 1, pulls an armature 36 over to the left, rocking a lever 21 downwards, whereby an abutment 21a thereon is moved clear of the teeth 20a of a disc 20. The disc 20 has a cam surface 20b which co-oprates with a pin 30b on a dog 30 pivoted at 27. Disengagement of the abutment 21a from the teeth of disc 20 allows the dog clutch 30 to be spring-urged into engagement with a toothed wheel 15 which is continuously driven from a shaft 13 by gears 14 and 17 (not shown) and now drives a register or adding wheel 24 to which is attached a cam 26 bearing digits 0, 1, 2, 3 and 4 in two series. Just before the third data position is reached, the dog 30 is arranged to be disengaged, whereby one or two units (according to the hole sensed) will have been entered on the adding wheel 24; cam contacts C8 close and energization of a relay R8 causes its a and b contacts to be transferred so that, upon closure of contacts C7, an impulse is directed to relays SM associated with the 1 ... 4 adding wheels 24 causing the levers 21 to be lifted and latched by members 35, and the abutments 21a to arrest the adding wheels. When a hole in the third position, Fig. 5a (representing 5 units), is sensed the circuit from the brush 12 and plug connection 55 follows a different path by virtue of the closure of contacts C1 causing energization of relay R1 and transfer of its contacts a. Through a line 65 and contacts Sc, R10a, another relay AM is energized which controls the dog clutch for a second adding wheel (46, Fig. 3, not shown) in each denomination. These wheels are for totalling 5-unit values only, and are stopped as the card reaches the fourth position by closure of contacts C4 energizing a relay R4 to transfer its contacts a whereby, when contacts C5 close the relays SM are energized to disengage the dog clutches The sensing of a hole in the fourth data position on the card representing 2 units, causes entry into the first adding wheels in a manner similar to that described above. Transfer is provided between the first and second adding wheels in each denomination, and also between the second adding wheels and the first wheels of the next higher denomination, by the usual contacts 39, 40, 41, Fig. 1 (49, 50, 51, Fig. 3, not shown) operated by the cams 26 (47, Fig. 3, not shown). These are represented in Fig. 5b and the circuit connections provide for long transfers in the usual way. Subtraction is accomplished by closing a switch 70 to energize a relay S and opening the switch 57 of the addition relay A. The relays AM, SM are then caused to operate to add the nines complement of the item to be subtracted.