GB839759A - Improvements in or relating to articles made from rubber or rubber-like materials - Google Patents

Abstract

839,759. Moulding hollow rubber articles. ANSELL, H. N., and LANDAU, L. Aug. 1, 1956 [Aug. 25, 1955], No. 24509/55. Class 87(2). [Also in Group XIII] A hollow article with an aperture in a wall thereof, e.g. a hot water bottle, is moulded from rubber or a rubber-like material by employing a mould having two parts 20 and 21, and a core 22 formed with an extension 23 to separate the mould parts. Two sheets 26, 27 of unvulcanised or partly vulcanised rubber are pressed between the core and the mould parts, and remain in contact with the latter when the mould is opened and the core removed. The mould parts are again closed, pressure is applied to the sheets to join them together whilst they are held against the mould parts by steam passing through a passage 31 in a core 30 inserted in the neck portion, and the material is vulcanised. In the primary moulding ridges 24 on the outer mould parts remove surplus material and a ridge 29 of rubber is formed around the periphery of the upper half of the article. The mould parts are heated during moulding and cooled just before opening, and the core is cooled or treated on its surface to reduce adhesion. The core 30 carries a ferrule 30b and after vulcanisation the core 30 is removed to leave the ferrule 30b fixed in the neck of the bottle to receive a stopper. In a modification, a neck and filling assembly is moulded and vulcanised separately from the main body of the bottle, to which it is later joined by vulcanization.