Patent GB-190110502-A (GB)
Title: Improvements in or relating to Machines for Compiling or Tabulating Statistics and other Numerical Data.
Inventor: HOLLERITH HERMAN
Filed: 1901-05-21
Granted: 1902-05-01
Abstract: 10,502. Hollerith, H. May 21. Calculating - apparatus. -Snm totals of numerical data under several heads are obtained by means of a series of adding-machines having e 1 e c t r omagnetic keys, any of which may be put into circuit by a pin box and a mercury cup switch, and punched selecting - cards. The construction of one of the adding.machines is as follows :-Ratchet adding-wheels 54 of thirty teeth, with three repetitions of zero and digits, are driven separately by pawls 64 on pivots 65 in a lever frame 62, which come into action because the keys trip latches 68 from them. The lever frame is connected by a link 72 to a crank-pin 73 on a wheel 74, and so is reciprocated when the wheel makes a revolution. Each key consists of an electromagnet 78 with a lever armature 82 hooking a tripping-pawl 86. The attraction of the armature lets the tripping- pawl obtrude into the path of the latch of the driving - pawl. Reversal of the wheel being prevented by check pawls 115, in the return movement of the lever frame the driving - pawls slip back over the teeth till they encounter a fixed rod 92, and, owing to their bevels, become detached again and relatched. Carrying is effected by means of levers 96 with pawls 98 ; three pins 103 at the zeroes on the wheels disengage latches 100 from the levers, and a set of cams 111 set spirally on a shaft 108 operates them in succession. Rollers 89 below each pawl latch set the acting tripping-pawls back again into engagement with the armatures, and the backward movement of the hook 91 of the tripping-pawl under a pin 90 detaches the armature if it sticks owing to residual magnetism. A resistance coit 94 takes, the, place of a zero key. The adding-wheels are set to zero again by partially turning the shaft on which they are mounted, whereupon prongs 120 of a comb 119 on a bail 118 catch the carrying-pins. The crank handle by which this is done must be turned back to zero, or otherwise a gap will be left in the circuit. The controlling-switch, as shown in Fig. 2, consists of a base 13 containing rows of mercury cups (ten in each row) over which the punched card 15 is laid, and of a box 14 holding rows of spring pins 16 on metal bars 175, Fig. 18, which dip into the cups at every hole in the card. The cups and electromagnets 78 of the keys are wired each to each as shown diagrammatically in Fig. 18, and the rows both of electromagnets and of pins are joined up in staggered pairs by wiles 95, 176 respectively, so that the selected electromagnets are in series. In the absence of a card, use of the switch will not send a current, as a special pin 19 enters a hole in the base and so will not thrust a contact-strip 21 against a bridge 22 between the box and the binding-screw 23. The controlling-switch also comprises rows of cups and pins according to the number of series in which the cards occur, and these are wired to a plug switch, Fig. 4, the cups separately to the fingers 133 and the rows of pins to the plugs 135. The number of a series is punched in each card, and the plugs are set in the bars 134 to the number of a particular series. Then, if a card of any other series is supplied to the controlling-switch, one or more of the dipping-pins is not in circuit through a plug, but through a bar 136, and a lamp or other signal calls attention to the discrepancy. The current, being supplied from the battery to the first bar of the controlling-switch through the wires 142, Fig. 13, returns from the last adding-machine through a switch 46 and an electromagnet 27. The electromagnet shifts a rotating shaft 28 so as to close a clutch 32, 33, by which the rotation is imparted to the shaft 42 of the adding-machine. A lug 45 on a wheel 44 in gear with the latter shaft accordingly recedes from the switch 46, and allows it to short-circuit the battery through the resistance 53, as the electromagnet of the keys have now done their work. Additional pins and cups are provided to cut out any one or more of the adding-machines when the cards are punched accordingly.