Patent GB-643515-A (GB)
Title: Improvements in or relating to photographic recording apparatus
Inventor: BAKER GEORGE THOMAS
IPC: G06K15/12
Filed: 1947-03-01
Abstract: 643,515. Metering telephone calls. AUTOMATIC TELEPHONE & ELECTRIC CO., Ltd. March 1, 1947, No. 5909. [Class 40 (iv)] [Also in Group XX] Apparatus for recording data, particularly data regarding telephone calls for fee-charging purposes, comprises in combination data - displaying equipment of the cathode-ray tube type and a photographic camera, in which each character is displaced on the screen of the cathode-ray tube and the film or paper on which the characters are recorded is advanced between each character display, means being provided whereby the position of each character on the tube screen is so displaced with reference to that of the others as to compensate for the film or paper movement between character displays to enable characters to be recorded side-byside. Preferably the film or paper is advanced in small steps between displays as this is found to facilitate accurate registration between the characters and titles which have been prerecorded on the film or paper. As shown, apparatus for recording data regarding telephone calls, viz. calling subscriber, called subscriber, time and date of the call, comprises a display unit 10 secured to a plate 21 having an aperture 67 and a camera 33 having pins 63, 64 which engage in slots 28, 29 in a pair of members such as 26a, 26b which snugly locate the camera against a felt bedding layer 27 on the plate 21. The display unit comprises a cathode-ray tube CRT and a lamp LP mounted on an insulated panel 15, a diffusing screen 17 for the lamp, and a photographic negative 16 (see Fig. 6), which is opaque except for the title words TO, FROM, TIME, DATE in the left-hand half of the upper third and a rectangular area corresponding to the central portion of the screen of the cathode-ray tube in the righthand half of the lower third as viewed from the camera. The title words are recorded on one half of a photographic paper strip, Fig. 7, before the call data, characters, which are to be recorded in line with the titles, are produced on the tube screen, the first characters recorded against the titles TO, FROM being the code number of the called or calling exchange followed by the four-figure number of the corresponding subscriber. The display unit is mounted within a housing having a mattblack interior finish and is attached to the plate in light-tight manner, a cap 13 allowing access to the tube and lamp. The camwa has a lens 46, shutter 49, and supply and take-up cassettes 53, 54 access to the latter being achieved by hingeing the back 40 at 41, a spring clip 43 normally holding the camera back closed. The shutter mounted in slideways 47 is urged closed by a spring, but when the camera is attached to the display unit housing a pin 32 thereon engages an arm 51 pivoted to the camera at 52 and pin-andslot connected to a projection 50 on the shutter and raises the latter. On lifting the camera, as when removing it from the plate 21, the lever 51 lowers the shutter to render the camera light-tight while it is still in contact with the felt bed 27. Control mechanism.-A uniselector of the type described in Herbert and Proctor's " Telephony " Volume 2, 2nd Edition, page 137, et seq., having a gear-wheel 56 added to the wiper spindle 55, is mounted on brackets 30, 31 by clips 103, 104. On energizing the selector magnet an armature pivoted on a knife edge is attracted against the action of a spring and moves a spring arm pawl clear of a ratchet wheel on the uniselector wiper spindle. On de-energizing the magnet the pawl returns to its rest position and in so doing moves the ratchet wheel on by one tooth, thus rotating the wiper spindle 55. Photographic paper feeding mechanism.-With the camera in recording position the gear-wheel 56 on the wiper spindle 55 meshes with a gearwheel 59 on a spindle 57 in the camera. Thus, as the wiper steps clockwise round the selector the spindle 57 moves anti-clockwise to feed intermittently the photographic paper strip 61 upwardly by engagement with resilient margins 58a of a bobbin-like roller on the spindle 57, a ball-bearing mounted roller 60 pressing the paper 61 against the driving roller when the camera back is closed. Guides such as 62a prevent lateral and forward and rearward movement of the paper. Operation.-Referring to Fig. 8, a starting impulse is supplied by connecting momentarily the line ST to earth, energizing relays FR, PU which in turn energize the slow release relay SR, the uniselector driving magnet LSM, and through selector level LS2 the relay SC which decreases the negative bias applied to the modulator grid of the cathode-ray tube so that the potentials derived from figure generating circuits FGY, FGX by way of figure selectors FSY, FSX, as described in Specification 624,089, and operated by an identifying circuit described in Specification 614,177, are applied by way of contacts 1 on selector levels LS3, LS4 to the Y and X-plates of the cathoderay tube to form an inverted laterally reversed image of a number representing the exchange called which is then recorded on the paper 61 in line with the title word " TO ". The energized magnet LSM in moving the armature opens the contacts LSMC and so releases relay PU and hence relay SC terminating the character display and de-energizing the magnet. The wipers on each selector level are thus moved on to the contacts 2, level LS1 thereupon acting as a hold-on for relay FR and also permitting re-operation of relay PU. The above sequence of operation is then repeated, the armature on returning to rest re-closing contacts LSMC, to record the called subscriber's number, the separate figures being produced on the tube screen by circuits 2FSY/2FSX ... 5FSY/5FSX, and the horizontal spacing h of the figures being obtained by level LS5 applying progressively increasing potentials to the X-plates by tapping off along the potentiometer YA-YF. Since the strip is stepped upwardly on each movement of the selector wipers, a potential deflecting the screen image downwardly by a compensating amount v is applied to the Y-plates, the values of the arms a, b of resistor YG being chosen so that the progressive variation of the potentiometer YA-YF causes uniform increases of the Y- plate potential. Alternatively, separate potentiometers may be connected to the X and Y- plates by separate selector levels. Since sequences such as contacts 1, 6, 11, 16 on level LS5 are linked together the successive individual figures corresponding to calling subscriber, time and date, which are produced by circuits FFSY/FFSX, TFSY/TFSX, and DFSY/ DFSX respectively, are recorded in vertical columns below the successive figures representing the subscriber called. Since only four figures are required for the date, contacts 15 on levels LS2, LS3, LS4 are left blank so that the tube remains biassed to cut-off, while contacts 18 on levels LS3, LS4 are connected to a dashforming circuit DY/DX. Contacts 21 . . . 25 are left blank except on level LS1 so that as the wiper traverses these contacts no characters are produced on the screen but the paper 61 is advanced the depth of one horizontal row. On the next step of the wiper its opposite arms engage contacts 1 and the cycle stops due to release of relays FR, PU. Release of relay FR completes the circuit through the lamp LP for the release time of the slow-release relay SR to record on the paper strip 61 the title words for the next-but-one call record. When the supply of paper has nearly exhausted a spring contact 113 in the camera normally held by the tensioned strip moves to engage a stationary contact 112 to operate an audible and/or visible alarm.