Load carrying assembly for an internal combustion engine

摘要

A load carrying assembly is disclosed for an internal combustion engine. The engine includes an engine block having a cylinder formed therein and having a cylinder head mounted onto the block. The cylinder head has a deck surface which closes off one end of the cylinder. A piston is reciprocally mounted in the cylinder and cooperates with the deck surface to form a combustion chamber. Air and combustion gases enter and exit the combustion chamber through intake and exhaust passages formed in the cylinder head and which terminate into intake and exhaust ports formed in the deck surface. The outer peripheries of the adjacent intake and exhaust ports form a bridge section therebetween having a maximum length which is less than twice the diameter of the larger of the intake and exhaust ports. Formed at least partially within the bridge section is a nozzle bore which also communicates with the combustion chamber. A sleeve having an enlarged portion on its outside diameter, is permanently fixed within the cylinder head such that one end will be aligned approximately adjacent to the deck surface of the cylinder head. The sleeve serves as a load carrying member which reduces the initiation of thermal cracks in the bridge section between the outer circumference of the nozzle bore and the outer peripheries of the intake and exhaust ports, respectively.