초록 ▼

A water-cooled, two-stroke crankcase compression internal combustion engine for powering a motor vehicle. The engine includes a piston, piston rings, and cylinder bore arrangement that are constructed to inhibit piston ring sticking by cooling the piston ring gaps by holding them against rotation an

A water-cooled, two-stroke crankcase compression internal combustion engine for powering a motor vehicle. The engine includes a piston, piston rings, and cylinder bore arrangement that are constructed to inhibit piston ring sticking by cooling the piston ring gaps by holding them against rotation and spraying fuel from a fuel injector toward the gap for cooling it. Overheating of the small end of the connecting rod is inhibited by surface treating portions of the piston to render them harder and less heat conductive. Scuffing of the piston, piston rings, and cylinder bore are reduced by surface treating the area of the head of the piston around the ring grooves so as to trap and retain lubricant. The surface treatment includes the steps of utilizing an acid wash to dissolve and remove silicon particles and subsequently alumitc treating the washed area.

대표청구항 ▼

[ We claim:] [1.] A method of forming a piston for an internal combustion engine from the group of materials consisting of aluminum and aluminum alloys, the piston being comprised of a head portion for forming in part a combustion chamber, the piston head portion having at least one piston ring groo

[ We claim:] [1.] A method of forming a piston for an internal combustion engine from the group of materials consisting of aluminum and aluminum alloys, the piston being comprised of a head portion for forming in part a combustion chamber, the piston head portion having at least one piston ring groove for receiving a piston ring, a skirt portion below the head portion for slidably engaging an associated cylinder wall, and a piston pin boss formed below the head portion and at least in part inwardly of the skirt portion for connection by a piston pin to the small end of a connecting rod, said method comprising the steps of surface treating at least said head portion for increasing its hardness and reducing its heat conductivity for protection from excessive heating by treating the piston surface with an acid bath to dissolve surface silicon and subsequently performing an alumite treatment on the surface.