Patent GB-1305107-A (GB)
IPC: G06K17/00
Filed: 1970-03-23
Abstract: 1305107 Statistical apparatus HARWALD CO Inc 23 March 1970 [24 March 1969] 13953/70 Heading G4M [Also in Division H3] A card having marked, unpunched areas is fed in steps past an optical sensing station the output of which is supplied to a shift register which is pulsed in synchronism with stepping of the card, and the shift register controls a punch spaced from the sensing station so that the marked areas on the card are punched. Cards.-Each card may correspond to a film which may be loaned e.g. to schools, and has a punched area on which the film number is recorded, an area on which legible information is recorded, a zero reference column (see below) and an area in which dates for which the film has been requested are punched, this area being manually marked prior to punching when a request for the film is received. The area round the marking positions is preferably grey to improve discrimination if the marker occupies less than the whole position provided or the card is not correctly registered when sensed. The requests take the form of a card on which the appropriate school number is punched and details of the film and requested date are manually entered, together with duplicate sheets. The request card and sheets are punched with the date in an area corresponding to the marked area on the (master) card at the same time as the marked area is punched, and the film number is also punched on the request card by sensing it from the master card. Sensing station.-Fig. 4. The card 13 is illuminated by a pair of tubular frosted lamps 80, 82 and black marks on it are detected by photo-FET's located at the ends of internally threaded and blackened bores. Individual lamps 272 ensure that the FET's remain fully illuminated when previously punched areas are aligned with the bores. Operation.-The master card is automatically skipped under control of a programme drum until the zero reference column is at the sensing station. This column contains half black and half white or grey, and the output of photo- FET 86 and transistors 98, 101, Fig. 9, should be about mid-way between their extreme values. At this point a relay 128 is energized to complete a feedback path for amplifier 110, 116 which ensures that the gate of transistor 110 is at earth potential, and any error voltage from transistor 101 is stored as charge on capacitor 106 so that correction is made during the subsequent sensing of the marking area (relay 128 being released). Further contacts 137-139 of relay 128 cause a small negative voltage to be stored on capacitor 106 after the zero adjustment operation if, due to failure of a lamp or FET 86, the maximum or minimum output is obtained during the zero adjustment. After a delay, corresponding to 24 columns say, the output of shift register 132 operates punch circuits 70 over contacts 210 to punch the master card with the requested date, and almost simultaneously (a delay is introduced at 178, 180) the request card is punched on a separate machine 75 synchronized with that on which the master card is processed. After punching of the master card it passes to a pin sensing station; relay 206 is energized, and the film number sensed by the pins 62 is supplied to control the request card punch 75.