CLOSED GALLERY PISTON HAVING PIN BORE LUBRICATION

摘要

A piston for diesel engines includes a piston body formed with a closed oil gallery and a pair of pin bosses having axially aligned pin bores whose surfaces are spaced from one another about their circumference across an intervening gap between the pin bosses. The pin bore surfaces are each formed with a recess which extends in the axial direction of the pin bores across the full width of each of the pin bore surfaces. An oil passage leads from the gallery to each of the recesses and feeds the recesses with lubricating oil from the gallery. The recesses act as retention basins or reservoirs which collect and supply the pin bore surfaces with lubricating oil during the fall cycle of the piston.