Blower for vehicle

A blower for a vehicle comprising:

• an intake duct having an indoor and outdoor air switching door mounted therein to open and close an indoor air inlet and an outdoor air inlet;
• a scroll case coupled to the lower portion of the intake duct and having a blower fan for forcedly blowing the indoor air and the outdoor air introduced to the inside of the intake duct toward an air-conditioning case;
• an air filter inserted into a receiving chamber disposed between the intake duct and the scroll case and having a filter portion and a frame portion;
• a filter cover detachably mounted on an entrance of the receiving chamber for sealing the receiving chamber;
• and
• an indoor air inflow means mounted on the upstream side of the blower fan for introducing some of the indoor air in an outdoor air inflow mode to thereby improve a heating/cooling performance,
• wherein the indoor air inflow means includes an indoor air inflow opening formed on the filter cover in such a manner as to be vertically overlapped with the air filter in a height direction of the air filter within a predetermined range, an auxiliary door coupled to the upper end of the inner surface of the filter cover via a coupling means to open and close the indoor air inflow opening, and an extension portion extended from the inner surface of the filter cover in such a thickness as to support a part of the lower part of the filter, and allowing the air filter to be spaced apart from the auxiliary door by such an interval as to prevent any interference between the auxiliary door and the air filter during the opening and closing action of the auxiliary door, and thus when the auxiliary door closes the indoor air inflow opening, the lower portion thereof is located to be lower than the upper portion of the air filter, wherein said extension portion is formed on the lower portion of the indoor air inflow opening so as to connect between the inner surface of the filter cover and the frame portion of the air filter and moves the indoor air introduced into the indoor air inflow opening toward the upper portion of the air filter, wherein the extension portion has a drain hole formed on a bottom portion of said extension portion to make the water introduced into the extension portion disposed in parallel on the one side of the air filter bypass the air filter and be introduced into the bell mouth of the scroll case.