Lubricating mechanism of pin connection pair of internal combustion engine

A piston for an internal combustion engine, comprising:

• a piston top portion;
• a piston skirt portion connected to the piston top portion and protruding axially from a peripheral portion of the piston top portion;
• the piston skirt portion including two pin seat portions structured and arranged to receive opposite ends of a pin connected to a connecting rod such that each of the two pin seat portions and the pin form a pin connection pair;
• a lubricating mechanism for the pin connection pair, the lubricating mechanism including:
• a lubricating passage through which a lubricating medium is flowable, the lubricating passage disposed within and extending inside the piston top portion;
• and
• an oil outlet orifice in fluid communication with the lubricating passage, the oil outlet orifice disposed in the piston top portion and arranged spaced apart from the piston skirt portion;
• wherein the oil outlet orifice has an opening facing axially away from the piston top portion;
• wherein the opening is disposed directly below a corresponding portion of the lubricating passage such that, via the opening, the lubricating medium is flowable directly to a gap that is defined between one of the two pin seat portions and the connecting rod when the pin is received in the two pin seat portions;
• and
• wherein the oil outlet orifice is tapered such that a width of the oil outlet orifice gradually decreases from a first end to a second end.

A piston for an internal combustion engine, comprising:

• a piston top portion;
• a piston skirt portion connected to the piston top portion and protruding axially from a peripheral portion of the piston top portion;
• the piston skirt portion including two pin seat portions structured and arranged to receive opposite ends of a pin connected to a connecting rod such that each of the two pin seat portions and the pin form a pin connection pair;
• a lubricating mechanism for the pin connection pair, the lubricating mechanism including:
• a lubricating passage through which a lubricating medium is flowable, the lubricating passage disposed within and extending inside the piston top portion;
• and
• an oil outlet orifice in fluid communication with the lubricating passage, the oil outlet orifice disposed in the piston top portion and arranged spaced apart from the piston skirt portion;
• wherein the oil outlet orifice has an opening facing axially away from the piston top portion;
• wherein the opening is disposed directly below a corresponding portion of the lubricating passage such that, via the opening, the lubricating medium is flowable directly to a gap that is defined between one of the two pin seat portions and the connecting rod when the pin is received in the two pin seat portions;
• wherein the oil outlet orifice extends longitudinally in a direction that, in an axially viewed plan view, is transverse to a central axis of a pin hole of one of the two pin seat portions;
• and
• wherein, in a longitudinal direction of the oil outlet orifice, the oil outlet orifice has a tapered shape and a width that gradually decreases from one end to another end.