Patent GB-754387-A (GB)
Title: Statistical record card sensing apparatus
IPC: G06F3/08
Filed: 1954-04-02
Abstract: 754,387. Statistical apparatus. INTERNATIONAL BUSINESS MACHINES CORPORATION. April 2, 1954 [April 6, 1953], No. 9716/54. Class 106 (1). A read-in circuit for use with a record-controlled machine comprises record sensing means for sensing a value stored in the record and a pulse generator including differentiallytimed actuating means for producing a series of pulses equal to any one of the respective values stored in the 55 record. A number of - kilocycle 4 pulses corresponding to the particular digit punched in any given column of a standard record card of the type shown in Fig. 2 is fed into electronic storage means 23. In Fig. 1, lead 1 connects one side of cam contacts 2, 3 and 4 to the positive terminal of a 40 volt D.C. supply. The other side of cam contacts 2, 3 and 4 are respectively connected as follows :-lead 21, contact brush 20, contact roll 19, lead 8, control panel wire 9, lead 10, to terminal 6A of " and tube " 6, lead 11 to terminal 5A of pulse generator 5. Record card 18 passes between contact roll 19 and read brush 17 and via lead 16 to terminal 7A of read-in switch 7. The pulse generator 5 is controlled by cam contact 4 and the generator delivers one pulse over lead 12 to terminal 6B of " and tube " 6 during index time 1. Similarly, two pulses are delivered during index time 2 and so on. Assuming that a particular card column passing under brush 17 has a five-hole punched in it, contact is made with roller 19 so that a circuit is completed from +40 volt terminal lead 1, cam contact 2, lead 21, contact brush 20, contact roll 19, read brush 17, lead 16, control panel wire 15 and lead 13 to terminal 7A of " read-in " switch 7. Read-in switch must have its terminal 7A simultaneously conditioned by a positive potential of the order of 40 volts in order to pass the pulse or pulses which appear at its terminal 7B to storage unit 23 so that five pulses are stored in storage unit 23. Referring to Fig. 3, " A " pulses of square waveform and approximately 50 volts magnitude at a frequency of 55 kilocycles are impassed via lead 20A upon terminal 6 of switch S5. Switch S5 is a pentagrid switch which is now conditioned by a trigger circuit T1 to pass the pulses in inverted form. Record cards are fed through the machine with the 12 edge leading so that card index times 12, 11 and 0 may be utilized in the control of trigger T.32. In the embodiment shown in Fig. 3 card index 11 is utilized for this purpose. The circuit shown in Fig. 5 functions in similar manner to that shown in Fig. 3 except that the card is a double deck record card, as shown in Fig. 4, having double the columns of a single deck card, i.e. 160 columns making it suitable for alphabetic as well as numerical data. The electronic decade counter is replaced by a binary 8 counter and the pulse generator functions to deliver 8, 4, 2 and 1 pulses in bursts at mechanically timed intervals synchronized with the movement of the record card. Referring to Fig. 3, each closing of cam contacts P-16, switches T-31 to its " on " position, the opening of cam contact P-16 has no effect on the position of the trigger. Each opening of the cam contacts P-60 switches trigger T-41 to its on position, the closing of cam contact P-60 has no effect on the position of the trigger. Cam contact P-64 opens at index time .5, resulting in trigger T-31 being switched to the off position. Cam contacts P-60 and P-63 open at card index time .5 to switch on triggers T-41 and T-13. Cam contact P-16 closes at card index time 1.1 and results in trigger T-31 being switched to its " on " position, terminal 9 of switch S5 is then conditioned and for every four " A " pulses impressed on terminal 6 of the switch a negative output pulse appears at terminal 7 of trigger T-45. The first negative impulse to the decade counter switches triggers T-41 and T-13 to " off position. The negative output pulse from trigger T-13 terminal 8 is impressed via lead 24 on terminal 6 of trigger T-1 causing trigger T-1 to switch to its off position. Switch S-5 is non-conductive when trigger T-1 is in its off position so that only a single positive output pulse appears at terminal 7 of trigger T-45 during card index time 1. Similarly, two, three, four, &c. pulses appear at terminal 7. during similar card index times. The positive output pulses from the pulse generator pass through cathode follower C-21 and result in a like number of positive pulses appearing on lead 34. These pass through invertor switch 1-13 and are thereby transformed into a like number of negative pulses which are trans. mitted through lead 35<SP>1</SP> to terminal 3 of switch 1-5. The purpose of the cathode follower C-21 and invertor switch 1-13 is to avoid excessive loading of trigger T-45. Specifications 671,341 and 741,597 are referred to.