Patent ID: 9441627
Filing Date: 2016-09-13
CPC Classification: F01C,F04C

Claim Text:
1. A rotor for a progressive cavity device, the rotor having a central axis and comprising: an outer tubular having a radially outer surface and a radially inner surface defining a rotor cavity, wherein the outer surface includes at least one helical rotor lobe; a filler structure disposed within the rotor cavity; a rotor head tousled to a first end of the outer tubular, wherein the rotor head includes a first port extending from an outer surface of the rotor tail to the rotor cavity; and a rotor tail coupled to a second end of the outer tubular, wherein the rotor tail includes a second port extending from an outer surface of the rotor tail to the rotor cavity; wherein the outer tubular is made of a first material having a first density and the filler structure is made of a second material having a second density that is less than the first density.