| 摘要 |
PURPOSE:To mold the profile of sliding throttle valve with high accuracy irrespective of the weld line by providing a slit and a gate at the opposite sides of a through-hole for inserting a measuring needle valve when molding sliding throttle valve. CONSTITUTION:When injection molding a sliding throttle valve 6, synthetic resin is flowed through a pair of gates 63, 64 of a metal die device to be combined at the position corresponding with an imaginary line 65 and filled in a cavity while forming a weld line. Since engaging slits 34, 42 are made at the side of said valve 6 on the imaginary line 65, synthetic resin fed through said gates 63, 64 will never been combined at the portion of the engaging slits 34 thus to prevent inflation at one side of said valve 6. Synthetic resin will neither been combined at the portion of the slit 42 to prevent inflation. Consequently, the outer diameter of said valve 6 at the portion sliding with a guide tube can be formed with high accuracy. |
