Method and apparatus for joining a mouth of a tubular member to an apertured disc

摘要

Method and apparatus for making a thermoplastic join between a mouth of a tubular member and an apertured elastic disc. The method comprises a first step of drawing an elastic disc over a tapered round former 22 to cause at least a peripheral portion of the disc to form a wall of material presenting an outer surface to be joined. The mouth of the tubular member 10 is drawn over the wall of material so as to overlay and fit the said mouth to the outer surface presented by the wall of elastic disc material. The former is expanded to press the wall of elastic disc material radially outwardly against the mouth of the tubular member and heat is applied to melt thermoplastic material in a ring of contact between the outer surface of the wall of material and the mouth of the tubular member. The thermoplastic material may be melted into thermoplastic cloth bonded to the surface of the elastic disc. The method is of particular application to joining the mouth of a tubular enclosure to a disc of elastic material in the manufacture of a waterproof cover for covering a dressing or plaster cast of the limb of a patient.