| 摘要 |
PURPOSE:To make fitting and demounting of a vent plug into and from a fitting hole of a metal mold easier, by making a guide supporting part which is located adjacent to an airtight part of a cylindrical plug main body and has many notched grooves extended along with the axial direction of the plug. CONSTITUTION:A vent hole 2 penetrating a cylindrical plug main body 1 to the axial direction of the plug, an airtight part 3 of a smooth surface occupying an end part of the plug main body 1, namely the part to be located inner side of the metal mold and having a little larger outer diameter than that of the inner diameter of a fitting hole of the metal mold, and a guide supporting part 5 having many notched grooves 4 on its outer surface extended from an end of the airtight part to the axial direction of the plug are set up. The vent plug is guided to the fitting hole in such a manner that the axis coincides with the axis of the fitting hole and supported therein as the fitting is carried out while the top peaks of the notched grooves 4 of the guide supporting part 5 are being contacted at the peaks with the inner wall of the plug-fitting hole 8. It is possible thereby to make the airtight part 3 shorter and to make driving and fitting the vent plug easier. |
