Oil separating device

An oil separating device for separating an oil mist from a blow-by gas, arranged on a flow passage of the blow-by gas, comprising:

• an oil separator including an inlet formed at one end thereof and an outlet formed at another end thereof opposite to the one end;
• a collision wall arranged at a downstream side of the oil separator, and including an uneven wall formed on a surface thereof to face the outlet of the oil separator;
• and
• a filter arranged between the oil separator and collision wall,
• wherein the oil separator includes a curved wall along which the blow-by gas spirals to coalesce together such that the oil mist in the blow-by gas forms a coalesced oil mist, the filter removes the coalesced oil mist from the blow-by gas, and the collision wall separates a remained oil mist remained in the blow-by gas passing through the filter,
• the collision wall further comprises a side wall having a width larger than that of the filter and a height higher than that of the uneven wall in a direction toward the filter and enclosing the uneven wall,
• the filter is arranged apart from the uneven wall to form a space between the uneven wall, the filter, and the side wall, and fit inside the side wall, and
• the filter has a width larger than the outlet of the separator.