Oil filtering device in a crankcase recess

An oil filtering device, in which a crankcase of an internal combustion engine rotatably retains a crankshaft inside, and an oil passage supplying oil to the crankshaft and a connection passage communicating with the oil passage are formed in the crankcase, comprising:

• a filter element disposed in a recess formed inside the crankcase;
• and
• a filter flange having a flat lid which has substantially a same shape as an opening of the recess and is fitted in the recess, a cylindrical extension part which extends outward substantially from a center of the lid and in which a communication passage is formed inside, and a connection part which is formed on a tip of the extension part and is fitted in the communication hole passage, wherein,
• the filter element is disposed to separate a space enclosed by the recess and the lid into an inlet space communicating with an inlet passage formed thereon and an outlet space communicating with the communication passage, and
• the oil introduced to the inlet space from the inlet passage is filtered by the filter element, discharged into the outlet space, and supplied to the crankshaft from the communication passage through the oil passage.