PURPOSE: To blow mold integrally a plurality of indendent pipes by forming openings for molding a plurality of independent pipes on a mold, communicating parts of said openings each other, inserting parisons extruded from a head of a blow molding machine through said openings, and then blowing air in respective parisons.
CONSTITUTION: An opening 8 for a main pipe and an opening 9 having a small diameter for a branch pipe are formed on molds 6 and 7. A communicating opening 34 for connecting said two openings 8 and 9 are formed. Air is blown into parisons 15 and 17 inserted through the openings 8 and 9 by means of blow pins 14 and 16 to carry out blow molding. The main pipes 1 and the branch pipe 2 are integrated through a spacer 13 and when said pipe is taken out of the metals 6 and 7, a pipe 3 combining the main and branch pipes consisting of the large diameter main pipe 1 and the small diameter branch pipe 2 heat fused to the spacer 13 integrally is manufactured.
SHIDARA YOSHIAKI
IWAWAKI AKIRA
ARAKI SATOSHI
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