Improvements in the Methods of and Apparatus for the Manufacture of Indiarubber Tubes and Covers, especially applicable for Pneumatic Tyres.

摘要

9805. Bert, E. April 28. Tyres, pneumatic.-Relates to the manufacture of india-rubber or similar articles, such as the outer covers, protecting strips, and air tubes of pneumatic tyres &c. In the form shown, the material from which the air tube 2 of a pneumatic tyre has to be manufactured is placed round a hollow crescent-sectioned mandrel m and is then tightly surrounded by the two correspondingly-shaped parts a, b of a vulcanizing-mould. By circulating a current of steam through the channel d in one part of the mould, and a stream of liquid at a low temperature, through the interior of the mandrel, the outer part r of the tread of the air tube becomes more completely vulcanized than the inner part s. When the air tube is made to take the shape which it will have when in use, the outer part r does not expand and hence the inner part s becomes compressed, so that the outer hard part resists a puncturing object and the inner part tends to close a puncture.