GB612752A - Roll chart road direction indicator - Google Patents

Abstract

612,752. Route-indicators. SKIDMORE, S. R. May 31, 1946, No. 16612. [Class 106 (iii)] In an indicator, wherein a roll chart unwinds from a feed spool to a take-up spool to exhibit representations of a route as a journey proceeds, the chart engages, at each end of an inspection aperture, rollers which are rotatable to draw the chart from the feed spool, and the take-up spool is driven from the feed spool by frictional contact through the chart itself, the linear speed of the respective parts of the chart at the peripheries of the spools being substantially equal at any instant. The spool of a roll chart of a route to be traversed is mounted on a spindle 53 in a bracket 51, spring biassed towards a bracket 52 carrying a spindle 54 for a take-up spool on to which the chart is wound after passing over rollers 19, 20 to be displayed through an aperture 23 in a hinged cover 22 so that the spools are in frictional contact and driven one by the other. Preferably, the rollers 19, 20 have fixed sprockets 33 engaging perforations along the chart edges and have gear-wheels 27 outside the case 21 engaging worms 28 driven through a wheel 31 by means rotating conformably with the road wheels. To give due warning of approaching turnings &c. plates are fixed in appropriate positions to the back of the chart so as to close one of a series of contacts 35 to 39 to complete a circuit to a corresponding lamp of a series 41 to 45 and illuminate the appropriate signal in a series 46 to 50 in the cover 22. To allow for manual adjustment for any discrepancy between the progress of the chart and of the vehicle, a coupling device is included in the gearing between the drive, which may be flexible, and the rollers. For a return journey the chart may be run backwards by interchanging the spools.