Patent GB-711575-A (GB)
Title: Improvements in or relating to record card feeding means
Inventor: KEEN HAROLD HALL
IPC: G06K13/07
Filed: 1952-04-29
Abstract: 711,575. Statistical apparatus. BRITISH TABULATING MACHINE CO., Ltd., and KEEN, H. H. April 29, 1952, No. 10756/52. Class 106 (1) A record card feeding and sensing mechanism for handling cards in succession comprises a shaft rotating at constant speed, means including a differential gear mechanism for driving the card feeding means, and means for intermittently moving the cage of the differential gear to reduce the speed at which the cards are fed by the feeding means for part of the sensing time. The apparatus is intended for use with record cards punched with coded combinations of holes representing data and may, for example, use four index positions 0, 1, 3 and 5. For sensing such a coded combination some form of translating device is necessary before the number represented thereby can be entered into an accumulator. In the apparatus described the cards are fed continuously but at varying speeds during parts of the feeding cycle. Cards 1 are fed from a magazine 2 in the usual manner by a picker knife 3 to feed rolls which are driven at a variable speed past the sensing brushes sets 73, 74, 77, 78. In order to obtain the variable speed drive of the feed rolls they are driven from a constant speed shaft through a gear train including a differential gear mechanism, the cage of the differential mechanism being movable under cam control. The cams are shown at 71 and 72, Fig. 2, and engage a sector 67 carrying rollers 69 and 70 for engaging the cam surfaces and a toothed quadrant 66. The member 67 is integral with the cage 61 of the differential mechanism which comprises a driving pinion 60, two idler pinions 62 and a driven pinion 63. The cams 71 and 72 make one revolution for each card feed, so that the sector 67 is rocked counter clockwise and clockwise about the shaft 68 once for each card feed. As the sector 67 rocks it turns the gear 66 and the differential cage 61 and consequently subtracts from or adds to the speed of rotation of the driven gear 63 of the differential. When the " 5 " hole is sensed it is necessary, for example, to enter a corresponding number of impulses into an accumulator. To achieve this the speed of feeding is reduced whilst the card moves to bring the " 3 " index print position under the brushes. The cams give such a movement to the cage 61 that the speed of the gear 63 is reduced to one sixth that of the gear 60. In between the " 3 " and " 1" index print position, the movement of the cage 61 is such that the gear 63 moves at half the speed of the gear 60. The sector 67 is then held stationary by the cams, so that the speed of the gears 60 and 63 is the same while the card moves to bring the " 0" index point position under the brushes. In the interval between the sensing of successive cards the cams move the sector back to the position it occupied at the start of card sensing. This movement turns the cage 61 in the opposite direction and the gear.63 is driven faster than the gear 60. Consequently, the average speed of card feed is the same as if the cage 61 had remained stationary. The reduced speed of the card during the sensing of the " 5 " and " 3 " index positions allows time for entering the corresponding number of impulses into the accumulator. The accumulator is similar to that described in Specification 704,860.