Valve seat inserts for internal combustion engines.

摘要

The improved valve seat insert (11) defines an aperture (18) through which the charge passes. The aperture (18) has an area to one side of a plane including the axis (16) of an annular valve-engaging surface of the insert (11) of which is greater than the area of the aperture (18) to the other side of the plane. The smaller of the areas is bounded by one or more curved sections. (17c).