Patent GB-382315-A (GB)
Title: Improvements in or relating to record-controlled statistical machines
Filed: 1931-07-24
Abstract: 382,315. Statistical machines. BRITISH TABULATING MACHINE CO., Ltd., Victoria House, Vernon Place, Southampton Row, London.-(Assignees of Bryce, J. W. ; Bloomfield, New Jersey, U.S.A.) July 24, 1931, No. 21240. Convention date, July 26, 1930. [Class 106 (i).] Total-printing.-A record-controlled statistical machine of the kind having record (card) feeding mechanism, counters, total-recording (printing) mechanism and means automatically to interrupt the card-feed and permit total recording, is characterized in that the means which initiate total recording is separate from the means which interrupt the card-feed and is so governed by a controlling member (listing shaft 15), which moves only when the card-feed is active, as to be inoperative whilst the controlling member is moving but operative when the controlling member stops. By this arrangement the machine may be stopped without the consequence of a total-printing operation, for example to replace a torn card. The invention is described as applied to a machine of the kind described in Specification 247,200, [Class 106 (i), Calculating &c.]. The listing shaft 15, driven one revolution each card cycle by the tabulating motor TM, carries a disc 24 with holes 25 in the path of light from source 26 to a photoelectric cell 27, which is coupled to an electromagnet 28 through a thermionic valve circuit which includes valves 30, 31 and a transformer 60 between the latter ; so that whilst the shaft 15 is rotating, and therefore the card-feeding mechanism is operated, the light is rapidly interrupted and the cell 27 produces a rapid succession of impulses. An amplified pulsating current is thus transmitted by the valve 30 to the transformer primary winding. The consequent pulsating current in the secondary and in the second valve 31, passes a current through magnet 28 sufficient to maintain its contacts 29 open. When the machine stops, disc 24 stops and either cuts off the light entirely or permits the light to shine steadily on the cell 27. In either case, the cell transmits no pulsations of current to the transformer primary ; there are no pulsations in the secondary or in valve 31 and the current through magnet 28 is only a small steady direct one, so that contacts 29 close. This establishes a circuit through contacts 36, 19 and relay 18 to start the reset motor RM, contacts 29 and 36 being in parallel with reset key RS. Contacts 21 (closed by 18) and P1 hold this circuit at certain times. When the card group changes, motor control relay 22 is de-energized, opening the contacts 23 and interrupting card feed and stopping shaft 15. This closes contacts 29 and initiates totalprinting as above. To stop the machine without total-printing, e.g. to replace a torn card, stop key 42 is depressed. Mechanically coupled to this key are contacts 41 which are thus opened to de-energize magnet 38 and open contacts 36. A switch 43 may be opened to prevent resetting and total-printing occurring automatically. Contacts 36 are for preventing the reset motor being started when main switch 37 is closed prior to commencing a tabulating operation, since the contacts 29 are then closed as the tabulating motor is stationary. These contacts 36 are closed early in the first card cycle, by which time shaft 15 is running and contacts 29 are open. At the end of a totalprinting operation, if switch 36<1> is closed, the motor TM will restart slightly before the reset motor comes to rest, so that the card-feed and listing shaft clutches are actuated and the disc 24 rotates to open contacts 29. Figs. 3 and 4 show a modification in which the contacts 56 (corresponding to contacts 29 of Fig. 2) are held open bv mechanical means whilst the listing shaft is running. Disc 44, loose on shaft 15, has a gear ring 45 of which the external teeth engage the wheel 46 of the fan 47 and the internal teeth engage a wheel 48 pivoted on an arm 50 loose on shaft 15. A wheel 51 fast on shaft 15 meshes with wheel 48 and arm 50 is pulled by spring 53 against a stop 54 so that an insulated block 57 on arm 50 closes contacts 56. Whilst the shaft 15 is running (clockwise in Fig. 3) the reaction of fan 47 causes arm 50 to move to the right against a stop 55, opening contacts 56. Since the circuits for the reset motor RM, effecting resetting and total-printing, are electrically separate from the circuits for the tabulating motor, the counting and printing mechanisms, and for the group control, these two sets of circuits may be connected to different sources of electricity, e.g. D.C. and A.C. sources respectively.