Patent ID: 7780405

Claim:
A blower system provided with: a centrifugal type blower fan for blowing air, taken in through a suction port from an axial direction, to an outside in a diametrical direction of said centrifugal type blower fan, a motor for driving rotation of said centrifugal type blower fan, a blower case in which is formed a spiral casing guiding air sent by said centrifugal type blower fan outward in the diametrical direction to a discharge port, and a motor holding housing for holding said motor, said blower case and said motor holding housing being separate members, said spiral casing being provided with an enlarged part enlarged in an axial direction to a side opposite from said suction port, said motor holding housing being provided with a holder storing and holding said motor, an extension extending from said holder in the diametrical direction of said fan, a circumferential wall connected with said extension and forming an inner circumferential wall of said enlarged part of said spiral casing, and a cooling air passage provided between said holder and said circumferential wall and guiding part of the air circulating inside said spiral casing to said motor, and said cooling air passage having an inlet into which air flows from said spiral casing and an outlet out of which air flows to said motor; wherein said inlet is provided with inclined walls formed inclined with respect to said diametrical direction so as to enlarge the cross-sectional area of the cooling air passage toward the outside in the diametrical direction of the centrifugal type blower fan.