US Patent 9360020 Self-cooling fan assembly

A self-cooling fan in configured with a vent feature that draws air into a fan housing and over a heat sink to dissipate heat generated by the motor and/or control unit. The self-cooling fan has a conduit with an attached end opening that couples with a cooling zone within the fan housing and extends along a portion of the fan blade(s). A vent feature is an opening in a conduit, at or near the extended end of the conduit, that allows air to exit the conduit. A vent feature may be a venturi feature. A venturi feature creates a vacuum within a conduit via outer diameter blade velocities interacting with venturi geometries when the blades are rotating, further promoting the drawing of air into the fan housing. A cooling channel allows air from outside of the fan assembly to enter into a cooling zone where a heat sink is configured.