Patent ID: 7487641

Claim:
A multi-stage microfabricated steam turbine engine comprising: a rotatable, disk-shaped rotor having a plurality of concentric rows of rotor blades disposed on a planar surface of the disk-shaped rotor; a stator having a planar surface facing and parallel to the planar surface of the disk-shaped rotor, the stator further having a plurality of concentric rows of stator blades disposed on the planar surface of the stator, wherein the plurality of concentric rows of stator blades are interdigitated with the plurality of concentric rows of rotor blades to form a multi-stage turbine; a pump for pumping a working fluid through the engine, wherein the pump is integrated into the disk-shaped rotor and wherein the pump is driven by the turbine; a generator system driven by the turbine to convert mechanical energy into electrical energy; an evaporator system for heating the working fluid; a condenser system for cooling the working fluid; an axial bearing for maintaining an axial position of the disk-shaped rotor, the axial bearing comprising at least one flow restriction that is located near a portion of the disk-shaped rotor and wherein a portion of the working fluid in a high-pressure steam state is directed between the at least one flow restriction and the disk-shaped rotor; and a journal bearing for maintaining a lateral position of the disk-shaped rotor, the journal bearing comprising a second at least one flow restriction that is located near another portion of the disk-shaped rotor and wherein a portion of the working fluid is directed between the second at least one flow restriction and the disk-shaped rotor.