Cylinder head with inwardly projecting cup plug in casting sand extraction hole for speeding up coolant flow

摘要

A cylinder head for an automotive vehicle has an inner wall serving to define the roofs of combustion chambers, and an outer wall spaced outward therefrom. A coolant flow plenum is defined between the inner wall and the outer wall, and a coolant flow path is defined through the coolant flow plenum. A hole through a portion of the outer wall of the cylinder head opens to a portion of the coolant flow path which has a relatively large cross sectional area, and serves for extracting an inner casting sand core used to create the coolant flow plenum during casting of the cylinder head. A cup plug is fitted into the casting sand extraction hole so as to block it, and this cup plug projects inwards into the coolant flow plenum so as to constrict the large cross section portion of the coolant flow path and to deflect flow of coolant toward other portions of the cylinder head that require high cooling.