Cooled valve for internal combustion engine

摘要

The valve comprises a plate-type head (4) joining onto a stem (5) working in a guide (7). A chamber (6) in the valve extends from the head to the stem and is partly filled with a working medium transferring heat from the head. The pressure in the chamber is such that when the engine is running the medium vaporises at the head end and condenses at the stem end. Water can be used as the medium, and part at least of the chamber can have a capillary inside wall (8). An insert with one or more capillaries can be contained in the chamber, which can be widened at the head end, at which point it can contain ribs. The valve guide can be water-cooled.