Patent GB-808544-A (GB)
Title: Facsimile transmitter for telegraph message blanks and the like
IPC: H04N1/00
Filed: 1956-12-21
Abstract: 808,544. Copying-telegraph transmitters. CREED & CO. Ltd. Dec. 21, 1956 [Dec. 29, 1955], No. 39003/56. Class 40 (3). In facsimile transmitter apparatus comprising means for scanning the subject-matter on a message blank at a scanning line position as the blank is advanced, a structure forming a receiving slot into which the message blank can be inserted and sheet-positioning members extending into the slot for engaging the leading edge of the inserted message blank to locate it in its correct starting position, a sheet-feeding mechanism operable in response to a start signal includes a feed roller actuatable into engagement with the blank for advancing it through the transmitter for the scanning operation, and means operative upon the actuation of said feed-roller retracts the sheet-positioning members from the message-receiving slot to permit the advancement of the blank. The slot 20 to receive the blank to be scanned is formed between a translucent plate 21, and a rear wall 23 carrying a translucent panel 25 through which the rear end of the sheet can be observed when the forward edge is in engagement with the retractable fingers 24. A horizontal rod 28 can be set in correspondence with the end of the message matter of the blank by a vertical rack 42 moved by a gear train 37 to 40, Fig. 4, operated by a gear-wheel 36 carrying an operating handle 34 and connected by a shaft 50 to a stop member 52 which in the position for the maximum length of message engages a fixed stop 58. A vane 54, Fig. 7, on the shaft 55 of a synchronous timing motor 56, indicated solely in Fig. 9, is held by a torsion spring 64 against the stop member 52, and after the sheet has been rapidly fed to the position at which scanning commences, a slow speed motor 53 takes over and continues the feeding until the vane 54 engages an arm 60 operating a switch 62 to restore the drive of the fast feed motor and to disconnect the timer motor. During the anticlockwise operative movement of the vane 54, the stop 52 is rotated in a clockwise direction against the stop 58, and when the timer motor is cut off, the vane 54 is restored by the spring 64 to engagement with the stop 52. When the sheet has been inserted, a signal from the distant station, when it is ready to record, operates an electromagnet 80 which actuates a time stamp 81 and platen 83, to print the date and time on the blank: Simultaneously, a second solenoid 86, Fig. 1, moves frame members 90 carrying a pressure roller 87 so that the blank is gripped between the roller 87 and the feed roller 88 connected by a chain 109 and sprockets 108, 110 to a feed roller 61. At the same time the supporting fingers 24 are drawn inwardly against the action of springs 95 and a switch 96 is operated to open the circuit of the magnet 80. Also the fast motor 63 is energized so that the blank is fed forward by drive roller 61 and pressure roller 112. The period of fast drive continues until a pin 114 mounted on the hub 113 of a wheel 115, driven through gearing from shaft 107 of roller 61, operates a switch 119 to connect the drive from a slow motor 53 to the roller 61. When the end of the message is reached, the vane 54 operates the switch 62 to reconnect the motor 63 which feeds out the transmitted blank, and effects further rotation of the wheel 115 until the pin 114 opens switch 118 to bring the motor 63 to rest and to release the solenoid 86 so that the fingers 24 return to their normal position. The blank is scanned in sequential transverse lines by an arrangement generally similar to that described in Specification 784,823. Control circuit arrangement, Fig. 9. When the power supply is connected, lamp 26 is illuminated and after the insertion of the message blank and adjustment of the stop 52, a start signal from a distant receiver operates clutch release magnet 166 of the scanning motor 129 so that the cam 169 rotates in phase with the recorder and cam 170 closes blanking contacts 171 to short circuit the transmission line 140 during the return path of the scanning beam. A start signal over conductors 144 also operates relay 164 which at contacts 160 extinguishes the lamp 26, and at contacts 162 operates solenoid 86 and also the time stamp solenoid 80 over the upper contact engaged by roller switch 96. A ribbon-step magnet is also energized to move the inking ribbon. At contact 162, a circuit is also completed through the normally closed switch 119 to operate relay 174. When the switch 96 moves to its lower position relay 174 at contact 176 energizes the fast feed motor 63 which rotates the cam 113 until the contacts 119 are changed over, effecting the release of relay 174 and the energization of the slow feed motor 53 and the timer motor 56. The released armature 175 of relay 174 also removes the short circuit of the outgoing line. When the end of the message has been reached, contacts 62 close and operate relay 186, which, at contacts 187, re-operates relay 174, and at contact 188 closes the circuit of conductors 142 initiating operations removing current from clutch magnet 166 and from relay 164 which releases, and at contacts 161 removes power from the slow feed motor 53. The timer motor 56, solenoid 86, feed motor 63 and relay 174 remain energized over a circuit closed by contacts 118 associated with cam 113. As the cam 113 continues to rotate, motor 56 is disconnected, and the timer vane returns to its normal position so that the switch 62 is opened and relay 186 released. Relay 174 remains operated over contact 119 until the cam 113 opens contacts 118 which release the solenoid 86, the fast feed motor 63 and the relay 174 which, on release, controls an electrical braking action for the motor 63 so that the cam 113 stops with the contacts 118 in open position.