Valved inner tube for pneumatic tyre - is not closed circular but sectioned with two overlapping sealed ends like sausage ring casing

摘要

Inner tube for vehicle pneumatic tyre is radially sectioned in circumferential direction, and thus has 2 free ends which are closed and come into contact with each other when the tube is being fitted. The tube has a valve at any convenient point along its length. The ends overlap and inner and outer portions are vulcanised together at the overlap. Mfr. comprises extruding an endless tubular blank, pinching it at predetermined intervals to form vulcanisable overlaps, conveying to vulcanising station, sectioning at overlaps, punching-out valve holes, powder-dusting interior, fitting valve.