Piston head for a spark ignition engine

摘要

A piston for an internal combustion engine of the spark ignition type has cavities formed in the crown in a pattern to cover approximately 16 to 18 percent of the piston head surface area. The cavities are formed in a pattern wherein no cavity edge is closer than approximately ¼ inch to ½ inch of any adjacent cavity edge or to the perimeter of the piston head. The cavities are generally cylindrical wall structures having a bottom in the form of a cone tapered to a central point. The depth of the cavity is approximately 55 percent of the cavity diameter.