US Patent 10371156 Ventilation fan having air bearing system

A ventilation fan includes a shaft assembly, a rotor, a motor housing, and a bearing housing. The shaft assembly defines a first port and a second port. The rotor has a rotor first portion disposed about a first portion of the shaft assembly and a rotor second portion that extends from the rotor first portion. The rotor first portion defines a rotor port. The motor housing is disposed about a second portion of the shaft assembly. The motor housing defines a housing port. The bearing housing is operatively connected to the motor housing. The bearing housing is disposed about a third portion of the shaft assembly.