Oil mist separator

A case for an oil mist separator, the case comprising:

• an inlet and an outlet through which blow-by gas flows;
• a separation section disposed inside the case and configured to separate oil mist contained in the blow-by gas;
• and
• an oil discharge section disposed at a bottom portion of the case and configured to discharge oil separated by the separation section to outside of the case, wherein
• the oil discharge section includes:
• a first discharge part having a first discharge hole for discharging the oil separated by the separation section;
• and
• a second discharge part surrounding the first discharge hole, and having a reservoir for storing the oil discharged from the first discharge hole and a second discharge hole provided at a bottom portion of the reservoir and configured to discharge the oil,
• the second discharge part further includes:
• a bottom wall having the reservoir;
• and
• a side wall extending upward from the bottom wall and having a passage providing fluid communication between an inside and an outside of the second discharge part, and
• the first discharge hole is opened to a side opposite to the passage on the side wall.