GB1388121A - Marking of carriageways - Google Patents

Abstract

1388121 Road traffic signals ENVIRONMENT SECRETARY OF STATE FOR 22 Feb 1973 [25 Feb 1972] 8720/72 Heading G4Q [Also in Division E1] A variable carriageway marker, which may form a variable marking line for a bus lane or for tidal traffic flow on a three- or five-lane road comprises an elongated flexible sleeve 10 of lowfriction material extending along an elongated platform 4 located below the carriageway surface (e.g. in a trough 33), the parts of the sleeve on either side of an intermediate part 11 hanging in loops 12, 13 whose relative sizes can be varied by means such as inflatable inner tubes 16, 17 to move the exposed layer 14 of the intermediate part 11 relatively to the carriageway. The layer 14 may have marking lines painted thereon. As shown, inflating tube 16 while deflating tube 17 (e.g. by means of a time switch-controlled roadside air pump, not shown), will cause the upper layer 14 to move laterally over the lower fixed layer 15 of the intermediate sleeve part 11, thereby exposing either an area matching the carriageway surface to indicate an absence of marking or exposing a different lane marking, e.g. to change a single or dotted white line to a double line at different times of the day. Rigid rubber or plastics tubes 18, 19 within the inflatable tubes 16, 17 serve to retain the sleeve loops in the trough 33. A low-friction nylon liner 5 bonded in the steel trough 33 has serrated edge portions retaining rubber wedges 24, 25. The platform 4 comprises a bolted-in I-girder covered with resilient material 9 to which the layer 15 is adhered. Heater elements 34 may be provided. The sleeve 10 may be formed either (as shown), by a one-piece envelope or by a single web having its longitudinal edges fixed to the platform 4. In an alternative embodiment, Fig. 2, a further inflatable tube 32 is provided between the layers 14, 15 to cause the intermediate part 11 to be raised when required to provide a resilient kerb which may be coloured white, the sleeve itself having wedge portions 26, 27 and thickened gap-sealing portions 28, 29 provided with kerb drainage recesses 30. In a modification, Fig. 3 (not shown), the lined built-up steel trough 33 of Fig. 1, is replaced by a lined or unlined rolled steel channel (35)-possibly with anchoring projections- and the steel girder 4 is replaced by a platform (38) of rubber or plastics which may be stiffened by pressure liquid in a longitudinal bore (39); the lower sleeve layer (15) may have a thickened portion (42) keying in a slot of the platform; additional inflatable tubes may be provided in upper spaces (43, 44) to pinch the intermediate sleeve part (61) in its adjusted position, and the spaces (43, 44) may be filled with lubricant. The Fig. 3 embodiment may be adapted to provide a raised carriageway marking by pumping fluid into the intermediate part (11)-with or without an additional inner tube-while allowing both loops (12, 13) to deflate so that the part 11 rises above the carriageway surface.