Articulated piston

摘要

An articulated piston for use in heavy duty diesel engines including a piston crown having an outer surface, a peripheral pending side wall and an inner surface having a pair of pin bosses extending downwardly from the inner surface with the inner surface and the pin bosses defining a hollow cooling cavity opening downwardly and extending about a circumference of the piston crown and a piston skirt with the piston skirt including a first longitudinal plane containing a pair of diametrically opposed bores for receiving a wrist pin for connection to the bosses of the crown and defining two semi-cylindrical thrust and non thrust surfaces of the skirt with a thickness of the non thrust surface being less than a thickness of the thrust surface and a second longitudinal plane, perpendicular to the first plane thereby dividing the piston skirt into four peripheral quarters. At least one of the quarters containing a cooling medium inlet through which a cooling medium, injected by a nozzle, can pass and impinge against the hollow cavity of the piston crown for cooling the crown. The piston skirt also includes a recessed tray formed in an upper surface of the skirt facing upwardly and opening toward the hollow cavity with the recessed tray extending for at least the peripheral quarter containing the cooling medium inlet and defined by a pair of substantially axially disposed side walls and a bottom wall extending radially inwardly between the side walls. The recessed tray is peripherally inclined towards a quarter diametrically opposed to the cooling medium inlet for conveyance of the cooling medium collected from the hollow cavity of the crown.