Patent ID: 6194798
Filing Date: 2001-02-27
Classification: F04D,H02K

Abstract:
An apparatus having a fan assembly comprisinga frame,a pulsed direct current electromagnet field assembly mounted to said frame,a fan blade assembly mounted relative to said frame for rotation about an axis and having at least two blades substantially permanently magnetized in the radial direction,wherein torque is applied to rotate said blade assembly when the magnetic field of said blades interacts with the electromagnetic field of said electromagnetic field assembly,said fan assembly comprises at least four blades, each blade having a N-S or S-N radial magnetic field orientation that is opposite to its adjacent blade, andwherein said fan assembly comprises first and second fan subassemblies in which all blades of said first subassembly are magnetized with the same radial N-S orientation and all blades of said second subassembly are magnetized with the same S-N orientation and the first and second subassemblies are coupled together.