Patent GB-415768-A (GB)
Title: An improved selector mechanism for telegraph and like selective apparatus
IPC: H04L17/18
Filed: 1933-03-01
Abstract: 415,768. Type-printing telegraphy. CREED & CO., Ltd., Telegraph House, Croydon.-(Assignees of Zenner, W. J. ; 1458, Keeney Avenue, Des Plaines, Illinois, U.S.A.) March 1, 1933, No. 6241. Convention date, July 8, 1932. [Class 40 (iii).] In an electric selector for use in type-printing telegraphy, in which selector members are set by power driven cams in co-operation with the selector magnet which responds to successive signal elements of a code combination, the magnet armature or a member directly controlled by the magnet imparts movement to a selector controlling member through a resilient coupling, the controlling member being temporarily held in one or other of its operating positions. The mechanical operations resulting from the setting of the controlling member in accordance with one element of a combination may thus overlap the receipt of the next element of the combination. The armature is mechanically fluttered to and from the magnet, synchronously with the signal elements, by further power driven cams and is only held by the magnet on a receipt of an element in which the line circuit is made. The selecting mechanism is of the kind comprising slotted permutation bars 39 each moved to one of two positions by a T-lever 38, one or other end of the T being engaged by a finger 11 which is angularly moved by engagement with one or other of the extensions 36 on the selector controlling arm 34 when finger 11 is longitudinally reciprocated by a bell crank 16 actuated by the corresponding cam 25 on a sleeve 21 rotated by clutches 23, 24 from a power shaft 22. The sleeve 21 also carries a stop arm 49, a toothed cam 42 for fluttering the armature 31, and a toothed cam 74 controlling the looking of the selective arm 34. On receipt of a code signal, the first or starting element de-energizes magnet 27 so that adjustable stop 66 on an arm 68 carried by the armature engages a plunger and bell-crank (not shown) to release a latch 54 holding a pivoted spring-controlled stop member 52 against which the stop-arm 49 on the sleeve 21 normally abuts. The sleeve is thereupon driven in a clockwise direction by shaft 22. The latch 54 and stop member 52 are carried by a plate (not shown) whose angular position in respect of the sleeve and stop arm is adjusted by a hand operated member 58 so that the operations of the various cam devices occur at the most favourable times during the reception of the signal elements. The next signal element (the first code element proper), if a marking one, energizes magnet 27 at a time when its armature 31 has been moved towards it by cam 42. The armature is thus held by the magnet and, through spring 45, moves arm 34 into the marking position, where it is locked by a spring controlled bell-crank 71 which is permitted by cam 74 to engage a projection 77 on arm 34. The arm remains locked until the first cam 25 has operated bell-crank 16 to reciprocate finger 11 which is moved against the upper stop 26 and actuates T-lever 38 to move the first permutation bar 39 into marking position. If the signal element had been a space, the armature would have followed cam 42 and selector arm 34 moved back in a clockwise direction and locked by bell-crank 71 before the cam 25 could reciprocate the finger 11, consequently finger 11 is against the lower stop 26 when it is reciprocated. The reremaining permutation bars are operated in similar manner, and when permanent line condition is restored, magnet 27 pulls up and stop arm 49 engages member 51 at the end of a shaft revolution. In the modification shown in Fig. 7, a polarized magnet 78 in response to a marking element moves its armature 79 into a position in which it holds a fluttering lever 81 (corresponding to armature lever 31, Fig. 1) out of contact with its operating cams 42. In a further modification, Fig. 8 (not shown), the magnet comprises a solenoid having an adjustable spring controlled plunger carrying a non- magnetic tongue which is adapted to be projected into the path of the fluttering lever. In another modification, Fig. 9, the tongue 101 controlling the fluttering lever 86 is carried by a moving coil 98 which takes the place of the line magnet of the previous arrangements and is mounted in the field of an electromagnet 93.