Throttle body for an internal combustion engine and its manufacturing method and a throttle apparatus using the same

摘要

A throttle body comprising a resinous main body having an intake passage therein and an annular member having a heat conductivity higher than that of said main body and attached to an inside wall of said main body defining said intake passage, wherein said annular member has a fluid passage entirely extending in said annular member, and a fluid inlet and a fluid outlet of said fluid passage are opened on an outer wall of said annular member exposed to an outside of said main body.