Patent GB-570097-A (GB)
Title: Improvements relating to travelling message signs and control means for electricallyenergisable elements
IPC: G09G3/00
Filed: 1943-12-09
Abstract: 570,097. Monogrammic signs. JENNINGS, H. W. K. (Trans-Lux Corporation). Dec. 9, 1943, No. 20632. [Class 118 (ii)] [Also in Group XXXVII] A switching arrangement suitable for travelling signs for the display of news or advertizing matter, comprises a bank of contacts each adapted to be connected to one of the elements of the sign, switches arranged in successive groups and each electrically connected to, but mechanically separate from, a terminal, the terminals connected to each of said groups being arranged side-by-side in a plurality of rows and sequentially engageable with the bank of contacts, and means for selectively and simultaneously closing certain of the switches of each group in succession as the contacts are moved relatively to the terminals. The selective and simultaneous closure of the switches is effected by means of a control system, Fig. 1, comprising a keyboard perforator 10 for a tape 11 which is advanced one step at each energization of transmitter 12, the impulses of which are passed to relays in a selector 14 which in turn operates a setting head 16 for an actuator 17 for the sign 19. The invention concerns the apparatus 16,.17 and its relation to the lamps of the sign, the latter being illuminated in such manner that letters, figures, or other symbols appear to move from right to left over its face. In a typical sign arrangement, each of 20 groups of lamps corresponding to one symbol to be represented comprises seven rows each of five lamps, and adjacent groups are spaced by one row of seven lamps. One side of each lamp is earthed and the other connected by lead 38 to a fixed plunger contact 41 co-operating with a movable contact 46. Contacts 41 are arranged in 20 groups, each of seven rows of five contacts in each, and with a spacing row, as in Fig. 3, and a gap of two groups' extent is left devoid of contacts. Contacts 46 have an additional two groups, that is, 22 in all, the extra two being employed for setting the pattern while opposite the gap in the groups of fixed contacts. Contacts 46 are mounted on a member 33 fast on a rotatable structure driven by a motor 24 and having a shaft 22, end parts 27, and a number of crossbars 28 equal to the groups of contacts 46, these cross-bars being earthed by say of slip ring 35 and contact 36. Each cross-bar conductively carries a number of rigid arms 50 and insulatingly carries a number of spring arms 52 so as to constitute one switch for each contact 46 and lamp in a group, the arms 52 being connected by leads 48 to the appropriate contacts 46. In order to close the switches appropriate for a particular symbol, electromagnets 76 are energized by the selector relays 14 and project plungers 73 to engage arms 53 pivoted to arms 50, so moving pins 55 clear of blades 52 and allowing them to engage arms 50 and make the circuit. This connection remains during the movement of the group over the whole range of contacts 41, whereupon wedgelike members 78 engage and lift the blades 52, and springs 54 restore arms 53 to the aligned position in readiness for a further setting action, the clearing and setting both being effected at the gap in the groups of contacts 41. In order to synchronize the above with the transmitter 12 and selector relays 14, the motor 24 operates a further switch arm 89, Fig. 2, through reduction gearing such that every group of movable contacts 46 as it leaves the sign is opened and reset in readiness, the switch comprising a wiper moving over a circle of contacts, Fig. 8 (not shown). For signs comprising more than the 20 symbols referred to, a further actuator (or actuators) is electrically connected to, and set in readiness by,. that symbol of the first actuator next to be re-set, so that there is no break in the display, Fig. 12 (not shown). A modified form of plungeroperated switch, Fig. 10, comprises a pair of contact arms 57, 59 and a movable bridge member 67 having straight edges 68 ... 70. The plunger 73 moves the member 67 so that flats 68, 70 lie against the arms 57, 59 and a rod 65 on levers 64 restores the member when arm 62, fast with lever 64, is engaged by re-set lever 71. The Specification refers to " Printing Telegraph Systems and Mechanisms " by H. H. Harrison, 1923, Chap. 5, and to U.S.A. Speoifition 1,110, 872.