GB687391A - Vehicle direction signalling system - Google Patents

Abstract

687,391. Road-traffic signals on vehicles. HOLLINS, R. J. May 4, 1951. No. 10556/51 Class 118 (ii). A direction signalling system for vehicles in which high resistance pilot lamps are in series with signalling lamps has flasher contacts connected in parallel with the pilot lamps so that when said contacts are closed. the signal lamps only light and when the contacts are open the pilot lamps only light. A battery 50 is connected via a main switch 53 (which may be the vehicle ignition switch) to a flasher 60 having three movable contacts 61, 62 and 63 normally making with fixed contacts 66, 67 and 68 respectively. The movable contacts are mounted on a pivoted bar 56 and loaded by spring 58 tending to open the contacts but normally held in the closed position by a resistance wire 65. Pilot lamps 15 and 35 are connected in parallel with contacts 61, 66 and 63, 68 and to terminals 12 and 32 of a selector switch 70, respectively in each case. The resistance wire 65 is in series with contacts 62, 67 and is connected to terminal 13 on the selector switch 70. Signalling lamps 10, 20, 30 and 40 are connected to terminals 11, 21, 31, and 41 respectively of the selector switch 70 which has a pivoted double-sector arm 72 carrying arcuate conductor strips 73, 74 arranged to selectively connect terminal 12 to terminal 11 or 21 and terminal 32 to 41 or 31 according to whether the arm 72 is moved counterclockwise. In whichever direction the arm 72 is turned an incompletely annular conductor strip 76 connects terminal 13 to 14 and completes the circuit for resistance wire 65. Supposing the switch 53 is closed, and the arm 72 moved counterclockwise, current then flows through the low resistance path of the flasher contacts to terminal and thus to signal lamp 10 and to terminal 32 and thus to signal lamp 40. Current also flows through the resistance wire 65 which expands allowing all three flasher contacts to open. The pilot lamps, in series with the selected signal lamps; now carry all the current and since these are of relatively high resistance the signal lamps are extinguished and only lamps 15 and 35 glow. The resistance wire cools and closes the flasher contacts and so the cycle is repeated. A similar action occurs in respect of signal lamps 20, 30, mutatis mutandis, if the selector switch is moved clockwise.