Patent GB-612028-A (GB)
Title: Improvements in or relating to card punching machines
Filed: 1946-05-15
Abstract: 612,028. Punching cards. BRITISH TABULATING MACHINE CO., Ltd. May 15, 1946, No. 14725. Convention date, June 22, 1944. [Class 31(ii)] [Also in Group XVI]. A machine which is especially applicable for punching statistical cards such as are used in connection with the Hollerith or like systems is constructed with means for feeding the cards from a hopper 64 to a position 68 in which the cards are stored ready for feeding through a punching station 70 through which the card is fed intermittently by feed rollers 380, 384, Fig. 14, which are driven by a friction clutch under control of a magnetically operated escapement which permits advance of the cards to the extent of the distance between the rows of perforations after each row has been punched. The punching magnets are operated by a keyboard 71, Fig. 1, or by a reproducing unit 73 which enables a number of copies of a master card to be obtained by means of electrical contacts which sense perforations in the master card and operate the punching magnets P.M. to give exact copies of the master card. During the feed of the card from the storage position to the punching station its back edge is raised so as to permit the succeeding card to be fed beneath the raised edge, so that it can be fed to the storage position before the preceding card is ejected from the punching station. The means for feeding the cards to the registering pins 400 at the punching station is described in the abridgment for Group XVI, and the feed-storage, punching and delivery mechanisms are mounted in casings which are adjustable about pivots 22 (Fig. 3a, not shown) coaxial with the driving shaft 36, Fig. 14, from which the various mechanisms are driven by helical gears. The feed wheel 380 which feeds the cards through the punching station is driven by a constantly rotating spider member 360 fitted with a friction surface tending to rotate an escapement wheel 354 on the shaft of the feed wheel 380. The wheel 354 is formed with 80 ratchet teeth, and with a blank space 356 corresponding to 8 teeth. The wheel 380 co-operates with an upper roller mounted in spring-depressed lever arms which are automatically raised to stop the feed by the action of a pin 414, Fig. 27, on the escapement wheel 354 which operates a lever arm 411 on a shaft 410 fitted with a lever which raises the upper feed roll. The escapement wheel 354 is normally held from rotating by a pawl 614 which engages a ratchet tooth, and by means of a spring-pressed clamping device 602 which engages the edge of the wheel and brakes it. At each punching operation electromagnets EM and CM, Fig. 27, are energized to operate the pawl 614 and clamp 602 to permit the wheel 354 to advance a tooth. The magnet CM is arranged to operate in advance of the magnet EM which is fitted with a time delay device such as a copper jacket. The punches 450 are raised to perforate the cards by means of levers 516 operated by push bars 494, Fig. 12, which are raised so as to bring teeth 496 on the bars into contact with rotating teeth 498 on a power driven shaft by means of rods 580 actuated by the armatures 570 of punch magnets PM which are energized on depression of the punch keys. The punchings pass up a tube 460 to a helical conveyer arranged in a tube 464, from which they pass to a delivery tube 471, Fig. 14, and a stripper plate 478 is provided. When the eightieth column of the card is punched the feed wheel assembly will rotate through a distance equivalent to eight columns due to the presence of the blank section of the escapement wheel opposite the holding pawl. If it is desired to release the escapement mechanism at any time when a card is not fully punched a release lever may be operated (650, Fig. 30, not shown), and this operates to move a rod 678, Fig. 27, to the right against the action of a spring- controlled lever 674. The rod 678 is fitted with an insulating finger 698 which operates switches to release the escapement wheel and to open the circuit to the punch magnets so as to prevent further operation of the punches while the card is being delivered. The bar 678 is held in operative position by a latch 686 which engages a slot 684 in the bar, but the pin 414 on the escapement wheel releases the catch 686 and a spring 702 then returns the bar 678 to its inoperative position. The device 73, Fig. 1, for reproducing a number of cards from a master card comprises a number of sensing pins 734, Fig. 26, which are connected to bars 724, 726 having connections with the punching magnets PM, and the master card is inserted in a slot in the casing 710 and the pins 734 make contact with bars 754 in positions corresponding to perforations in the master card when the panel containing the bars 754 is pressed against the master card by operation of a presser plate 766 by means of an eccentric operated by a lever 778. Operation of the presser plate closes a switch RC. The circuits through the bars 724, 726 are controlled by a distributor 704, Fig. 14, mounted on an extension 350<1> of the shaft 350, and formed of revolving conductor arms 816, which move over a series of insulatedly mounted contacts 810, 812 connected in the circuits of the alphabetical and numerical punches respectively. In a modified form of reproducer the master card is inserted into a slot of a drum and the apertures in the card are sensed by a row of spring contacts arranged across the drum. When a master card is being copied the punching devices may be fitted with an automatic skipping device which is set to omit information from one or more selected fields of the cards undergoing punching. The means for enabling this skipping and also to permit of X-skipping when a card is being punched under control of the keyboard comprises a skip index wheel 850, Figs. 14 and 16, formed of insulating material and fitted with a series of slidable pins 860 formed with heads 861. The pins are movable laterally by pivoted pushers 893, 895 operated by depressing keys 880, 882, to set the pins for automatic or X- skipping respectively. The pins may be set so that their heads engage guide channels 868, 870, Fig. 23, in a fixed guide member to hold the pins in neutral position or in a position for X-skipping. When set for automatic skipping the heads are flush with a circular ring 876, Fig. 23, secured to the rear face of wheel 850 by rivets 878. All the pins bear against a pair of conductive coil springs 863, and the circuit to the escapement magnets is completed by a conductor 865, Fig. 16, and by contact brushes 916, 917, Fig. 21, not shown, which are mounted on a tiltable cradle 912. The pins 860 may be re-set to neutral position by inclined cam surfaces on a slide 936 which can be moved along a channel-shaped guide 932 to bring the cam surfaces into the path of the pins so as to move these to neutral positions. The circuits to the operating magnets comprise electric valves, and a magnetically controlled clutch is provided to limit the rotation of a cam shaft 138 which controls the operation of the feed mechanism to one revolution for each card fed. The electrical circuits are described in connection with Figs. 32, 33 not shown.