Oil pan of internal combustion engine

An oil pan mounted on a bottom part of a crank case of an internal combustion engine, the internal combustion engine including a first oil return passage extending from a cylinder head to an oil pan through a crank case and a baffle plate disposed at a bottom of the crank case, and a second oil return passage extending directly from the cylinder head to the oil pan, wherein:

• the oil pan collects oil returned from said first oil return passage and oil returned from said second oil return passage;
• the oil pan comprises an oil introducing means;
• said oil introducing means comprises:
• an oil introducing plate having an insertion hole for receiving a sucking portion of an oil strainer, the oil introducing plate extending from the periphery of said insertion hole toward a side wall of the oil pan,
• wherein the oil returned from said first oil return passage is introduced to flow along said oil introducing plate via an oil falling hole formed in said baffle plate:
• a plurality of inclined wall portions mounted on a bottom portion of the oil pan in the vicinity of the side wall of the oil pan in order to support said oil introducing plate;
• and
• opening portions formed between the inclined wall portions and said bottom portion of the oil pan,
• wherein the oil introducing plate of the oil introducing means is located just below said oil falling hole formed in said baffle plate.