Patent GB-754740-A (GB)
Title: Apparatus for sensing perforated statistical records, e.g. record cards
Inventor: DAVY JOHN COLIN
IPC: H01J25/18
Filed: 1954-03-12
Abstract: 754,740. Statistical apparatus. POWERS-SAMAS ACCOUNTING MACHINES, Ltd. March 1, 1955 [March 12, 1954], No. 7299/54. Class 106 (1). Pneumatic card sensing apparatus.-In apparatus for sensing perforations in perforated statistical record cards by means of compressed air, the card is positioned between upper and lower members 25, 28, Fig. 1, and a sealing frame 33 is movably mounted in a recess in the lower member so as to be normally spaced from the upper member to allow the record card to be inserted, the compressed air, when applied, being adapted to force the sealing frame against the record card and to seal off the area thereof to be sensed. A base plate 12, Figs. 1 and 3, has air inlet openings 13 communicating with ring channels 26, diagonal channels 27 and secondary channels 27a cut in the surface. An elastic diaphragm 29, Fig. 4, is clamped in place on the surface of plate 12 by a clamping member 28 which is secured by screws to wall portions 24 surrounding channels 26, and forms the lower, card-supporting, member. The clamping member 28 has window openings corresponding to the periphery of the rectangular ring channels 26 as shown in Fig. 4. Over the area of these openings the diaphragm is perforated at 27b, Fig. 3, so that air can pass from the secondary channels 27a to apertures 31, Fig. 1, formed in air delivery plates 30 clamped over the diaphragm in the centre of the openings. The apertures 31 in plates 30 are formed in lines interconnected by channels 32. The sealing frames 33 surround the air delivery plates 30 and fit within the openings in clamping members 28 so as to be capable of movement in a vertical direction. Each sealing frame overlies the rectangular channel 26 and is secured to the diaphragm 29 by screws 36, springs 39 connected to it by pins 37 urging it to the lowermost position. The card-engaging face 34 of the frame is narrow compared with the lower face, e.g. about one third the width. When a card is in sensing position the air pressure is applied as described below and, by acting against the under side of the diaphragm in the areas of channels 26, lifts the sealing frame against the action of springs 39 into contact with the card so that the narrow face 34 seals off the area within the frame. Air pressure applied through the air delivery plates 30 passes through the apertures in the record card and into corresponding bores 41 in the second element 25 where it acts on pistons 45. The pistons serve to control the functions of the machine to which the sensing apparatus is fitted, e.g. through Bowden cables 48. Control of air pressure; card feeders and detectors.-Compressed air is applied to the openings 13 through a control valve 15, Fig. 1, having a control spindle 16 acted upon to open the valve by an arm 17 on a rock-shaft 18. The other end of shaft 18 carries a lever 19, Fig. 2, having a follower 20 at one end running on a cam 21, a spring 22 serving to turn the lever to the cam engaging position. The valve 15 is opened to apply sensing air pressure once during each rotation of shaft 23 which is constantly driven. An eccentric 54 on shaft 23 is connected by link 53 to an arm 52 on a second rock shaft 51. An arm 50, Fig. 1, on this shaft operates a slider 49 separating record cards from the bottom of a stack 40 and forwarding them to feed rollers 55. Cards are fed by the rollers 55 into the sensing position under the member 25 and they are located by a rising and falling front stop 56. This is controlled by a cam 57 on shaft 23 acting through a spring-loaded lever. Another cam 65 on shaft 23 acts through a link 62 to cause anticlockwise movement of a lever 61, shaft 60 and arm 59, the link being moved in the other direction by return-spring 66. A detector pin 58 slidable vertically in a bore in the plate 12 and member 25 is lifted during each card sensing cycle by the arm 59. If no card is present the pin is allowed to rise into a bore in upper member 25 and shaft 60 rotates under the action of spring 66 to position an arm 67 in the path of a pin 68 on the other end of lever 19 controlling the operation of valve 15. The lever 19 is normally urged in a clockwise direction to open the valve 15 by spring 22, but this movement is prevented by the arm 67 so that no air pressure is applied in the absence of a card. When a card is properly in position the detector pin is prevented from lifting and so that the spring 66 cannot rotate the shaft 60 to move arm 67 to the blocking position. The valve operating cam 21 releases the lever 19 for clockwise movement just after the cam 65 releases the link 62 to cause the detecting movement of pin 58. When a card is present the shaft 18 is allowed to rotate and valve 15 is opened to apply air pressure to the card. Record cards.-The record card C, Fig. 8, has been provided with pin hole perforations 43 in data-indicating positions 42. These pin-holes are sensed and caused to effect operation of a punching machine to which the sensing apparatus is fitted, the arrangement being such that the card, after being sensed, is passed to the punching machine to make perforations 69 in card positions corresponding to those in which the pin holes were sensed. The perforations 69 are in the " normal " horizontal row positions while the data-indicating positions are " interstage ", i.e. located between the normal horizontal rows of the card.