PURPOSE: To prevent the occurrence of a crack starting from a spot where an inner wall of an inner tube in a pinch sealing part of a mount creeps into the melted part with an acute angle by providing a process to apply pressure to the inside surface of the inner tube from the open end of the inner tube with gas after pinch sealing.
CONSTITUTION: While the sealing part of a pinch-sealed mount is still in a softened state, inside pressure of inner tube 1 is raised by blowinggas 13 from a nozzle 10 into an open end of the inner tube 1 for widening the inner wall of the inner tube at the base 9 of the inner tube 1 in the softened state to enlarge the angle θ°. One of the methods to vaise the inside pressure of the inner tube 1 is utilization of dynamic pressure. Thereby, the softened part only is deformed for widening the spot where the inner tube of pinch sealing part of the mount creeps into the melted part with an acute angle, so that the occurrence of a crack can be prevented.
TAKADA HIROSHI
YAMAMOTO TOKIMASA
