Patent GB-143240-A (GB)
Title: Telegraphic transmitter
IPC: H04L25/42
Filed: 1920-05-12
Abstract: 143,240. Siemens & Halske Akt.-Ges. Feb. 28, 1919, [Convention date]. Transmitting systems and apparatus.- The signal impulses of a code telegraph system are stored in condensers and are automatically transmitted to line. The impulses are set up by means of a keyboard which is locked automatically when the rate of setting up exceeds the rate of sending, and means are provided to stop the transmission when the rate of sending exceeds the rate of setting up. The keyboard transmitter A comprises two keys 1, 2 associated with fixed contacts 31, 32, 33, 34 and mounted upon a rod 41 in such a manner that the operation of either key closes switches 27 and 36. The contact 36 controls the circuit of a stepping-magnet 11, and the contact 27 controls a circuit connected to the middle point of a battery 35. A magnet 69 shunted by a signal lamp 26 controls a member 71 adapted to lock the keys 1 and 2 against operation. The signal storage device B comprises six pairs of condensers 45, 47; 52, 53; 54, 55, &c., a pair of segmental conducting rings 3, 4. a brush-arm 10 operated by the setting magnet 11 through a lever 48 and pawl and ratchet mechanism 12, 13, and a brush arm 9 operated by a motor 19 through a clutch 17, 18. The condensers 45, 47 are connected between contact segments 43, 44 respectively and a common lead 46 and the other condensers are similarly connected. The clutch element 17 is controlled by magnets 38, 39 through a lever 40. The transmitter C comprises segmental conductors 23, 24, connected to the brushes 7, 8 of the storage device B through the leads 60, 61, a brush arm 22 operated by the motor 19, and a polarized relay R, the armature 28 of which controls the connexion of the line L to the terminals of a divided battery 29, 30. The operation of the arrangement is as follows : Assuming the brush-arm 10 to be in the position shown and that the key 1 is operated; under these conditions the condensers 45, 47 are charged with currents of opposite polarity and the stepping magnet 11 is energized. The release of the key 1 opens the charging circuits of the condensers and allows the arm 10 to be stepped around in an anti-clockwise direction thereby causing the brushes 5, 6 on the arm 10 to engage the contact segments 50, 51, when a further operation of the keys 1 or 2 or both charges the condensers 52, 53. The brushes 7, 8 on the arm 9 pass successively over the contact segments 43, 44; 50, 51, &c. to connect the segments 23, 24 of the transmitter C to the segments 43, 44: 50, 51, &c. when the condensers 45, 47 ; 52, 53, &c. discharge through the polarized relay R which operates to send positive or negative impulses to line L according to the charge on the condensers. To lock the keyboard when the rate of setting up the signals exceeds the rate of sending, a contact 67 is provided on the hub of the arm 9 and an additional contact brush 66 is placed on the arm 10. When the brush 66 engages the contact 67, the key-board locking magnet 69 and a signal lamp 26 is energized from the battery 37 and this circuit is not broken until the arm 9 is advanced. To stop the transmission when the rate of sending exceeds the rate of setting up, a contact 73 is provided on the hub of the arm 9. When the contact 73 engages the brush 66, the magnet 38 is energized from a battery 37 through a circuit containing the contact 73, brush 66, contact brush 20 on the transmitter arm 22, and contact segment 25 on the transmitter. The magnet 38 operates to disconnect the clutch elements 17, 18. When the arm 10 is advanced, the brush 66 engages a contact 76 on the hub of arm 9 to complete the circuit of a magnet. 39 which operates to engage the clutch elements. The Specification as open to inspection under Sect. 91 (3) (a) states that the condensers may be replaced by polarized relays. This subject-matter does not appear in the Specification as accepted.