FIXING STRUCTURE OF INTAKE PORT LINER, FIXING METHOD OF INTAKE PORT LINER, AND PREFORM

摘要

PROBLEM TO BE SOLVED: To easily and stably fix an intake port liner to an intake port.SOLUTION: A port liner 40 composed of a resin material having heat conductivity lower than that of a cylinder head 20, is fixed to an intake port 22 formed on the cylinder head 20 and having a plurality of branch passages 26 branched and extended toward a downstream side. An insertion process for inserting a heated bottomed cylindrical preform 50 into the intake port 22, a stretching process for stretching the preform 50 into the shape along an inner peripheral face of the intake port 22 by blowing the air into the preform 50, and a removing process for forming an outlet opening of the port liner 40 by removing a bottom portion 56 of the preform 50 after the stretching, are provided. The preform 50 has two branch pipes 54 respectively corresponding to two branch passages 26 of the intake port 22, and two branch pipes 54 of the preform 50 are respectively inserted to two branch passages 26 of the intake port 22.SELECTED DRAWING: Figure 3