| 摘要 |
1,129,473. Laminates. DUNLOP CO. Ltd. 14 Oct., 1965 [31 Oct., 1964], No. 44507/64. Addition to 974,131. Heading B5N. [Also in Division E1] A portable platform for use as a temporary road, catwalk or bridge comprises a flexible composition having embedded therein at least two layers of individually flexible transverse metal cords with a textile reinforcement therebetween and a layer of longitudinal metal cords, the separation between the transverse layers being sufficient to confer transverse rigidity upon the platform as a whole. The longitudinal cords may be either continuous, or discontinuous and arranged in parallel overlapping relationship. Suitable metal cords may be prepared from 6 to 24 strands of zinc-plated steel wire rubberized by calendering with natural rubber composition containing a cobalt salt. The textile reinforcement may comprise one or more layers of woven fibres or weftless cords of e.g. cotton, polyamide, polyethylene terephthalate, polyolefine, regenerated cellulose or polynosic fibres. An example has two layers of transverse metal cords between which are disposed a layer of longitudinal cords, then four layers of cotton fabric frictioned with vulcanizable rubber composition and a filler layer of vulcanizable rubber composition in that order, together with outer rubber layers, the upper one being roughened or ribbed as required. Instead of natural rubber the flexible composition may be synthetic rubber or resin, e.g. plasticized polyvinyl chloride. A second longitudinal steel cord layer may be provided. Lengths of platform may be joined end to end by incorporating castellated end portions (as described in Specifications 1,058,085 and 1,058,086) and inserting a tie-pin through interengaging segments and the platform may be anchored to a castellated plate in the same way. |
