US Patent 11274670 Blower

A blower includes a centrifugal fan and a partition wall disposed in a suction space in the centrifugal fan. The partition wall has a base portion extending along a fan central axis to partition the suction space into a first space for a first fluid and a second space for a second fluid. The partition wall has an enlarged portion connected to an end of the base portion on another side of the fan central axis. The enlarged portion covers a part of a fan boss. A clearance passage is defined between the enlarged portion and the fan boss and has a first space side opening and a second space side opening. The enlarged portion is biased in the suction space to the second space such that a pressure at the second space side opening is less than a pressure at the first space side opening.