| 摘要 |
PROBLEM TO BE SOLVED: To apply a pressure in an injection step of rubber and improve mechanical strength by providing an injection hole of rubber and a fluid feed hole in a die. SOLUTION: The die 1 is formed to hold, from above and below, a core material 2 corresponding to the external shape of a connection part of a cable. A recess 3 corresponding to the external shape of an insulating rubber is provided in the die 1. If the die 1 is used, by introducing a fluid from a fluid feed hole 5 into the die, injection can be effected, while pressure is applied to the rubber. That is, before injecting the rubber, the interior of the recess 3 is kept at a predetermined pressure, and under such conditions, the die is charged with the rubber. Even in the injection step, injection is continued to apply pressure to the rubber by means of fluid. Thus, a defect such as a void is not produced in the rubber in the initial stage and hence mechanically weak part is prevented from being produced in the rubber. |
