GB190814554A - Improvements in Electrical Vulcanising Apparatus. - Google Patents

Abstract

14,554. Allman, P., and Leeson, G. W. T. July 9. India-rubber &c., vulcanizing.-Electrically-heated vulcanizers are made flexible so that they may be easily adapted to the shape of the article to be vulcanized. The heating-element is a looselywoven screen of resistance wire 1, Fig. 2, with or without a flexible outer covering 2 of asbestos, vulcanized rubber, leather, cork strips, &c. In some cases, several screens are employed side by side connected in series and, if desired, with mica plates interposed. The backing is preferably in the form of a gaiter consisting of three strips 7, 7, 8, Figs. 4 and 5, united by a strip 9 and provided at their ends with loops 10, which take over hooked yokes 14. The whole is tightened by turning screws 13 which bear upon a mandrel 12. Fig. 5 shows how the vulcanizer 2 may be used transversely of a tyre cover, a lead strip 15 being used to press it well against the beading. The device may be employed for jointing an inner tube by wrapping it around the joint after preparation, for repairing an inner tube on the flat by stretching it across a bench fitted with clamps, or for vulcanizing a complete tread or for wrapping round a mandrel, it may be made in the form of a tape adapted to be wrapped round the tyre. Fig. 8 shows another modification in which a number of lozenge-shaped heating-elements 2 are connected in series and arranged to break joint with the elements 21 of the jacket.