Coriolis effect mass flowmeter using concentric rotors

A Coriolis flowmeter comprising:

• a fluid containment housing;
• an outer rotor positioned within said housing and having a center axis of rotation,
• a recess in said outer rotor coaxial with said center axis of rotation;
• a Coriolis rotor at least a part of which is positioned in said recess and having a center of rotation coaxial with said center axis of rotation;
• a plurality of openings in said Coriolis rotor with each of said openings extending from an outer periphery of said Coriolis rotor to a center recess of said Coriolis rotor;
• a plurality of openings in said outer rotor with each of said openings extending from the outer periphery of said outer rotor to said recess of said outer rotor with at least some of said openings in said outer rotor being substantially aligned with corresponding ones of said plurality of said openings in said Coriolis rotor;
• a fluid inlet for applying received fluid to an inner chamber of said housing;
• a fluid outlet for discharging said fluid from said housing;
• means including said housing and said outer rotor and Coriolis rotor responsive to a receipt of said fluid by said fluid inlet for extending said fluid through said openings of both said outer rotor and said Coriolis rotor to said fluid outlet;
• means including said means for extending for rotating both said outer rotor and said Coriolis rotor about said center axis of rotation using energy derived from said fluid while said fluid is extended through said openings in said Coriolis rotor and in said outer rotor;
• said means for rotating comprising means for causing said outer rotor and said Coriolis rotor to rotate in response to said extension of said fluid;
• means responsive to Coriolis forces generated by said fluid extension and to a concurrent rotation of said outer rotor and said Coriolis rotor for causing said Coriolis rotor to assume an angular offset from said outer rotor about said center axis of rotation;
• means for generating output signals indicative of the magnitude of said angular offset;
• and
• means for receiving said output signals to derive the mass flow rate of said fluid.

A method of operating a Coriolis flowmeter comprising the steps of:

• extending a received fluid flow through fluid paths of a rotor positioned within a housing and having a center axis of rotation, as well as through fluid paths of a Coriolis detection means having a center of rotation coaxial with said center axis of rotation of said rotor;
• rotating both said rotor and said Coriolis detection means about said center axis of rotation using energy derived from said extension of said fluid while said fluid is extended through paths of said rotor and said Coriolis detection means;
• said Coriolis detection means assuming an angular offset from said rotor about said center axis of rotation in response to Coriolis forces generated by said fluid extension and the concurrent rotation of said rotor and said Coriolis detection means;
• generating output signals indicative of the magnitude of said angular offset;
• and
• deriving the mass flow rate of said flowing fluid in response to the generation of said signals.

A method of operating Coriolis flowmeter comprising the steps of:

• extending a received fluid flow from a fluid inlet of said Coriolis flowmeter through a plurality of openings in an outer rotor positioned within a housing of said Coriolis flowmeter as well as through a plurality of openings in a Coriolis rotor at least a part of which is positioned in a recess in said outer rotor;
• said outer rotor and said Coriolis rotor having a common coaxial center axis of rotation;
• each of said openings in said Coriolis rotor extending from the outer periphery of said Coriolis rotor to a center recess of said Coriolis rotor;
• each of said openings in said outer rotor extending from an outer periphery of said outer rotor to said recess of said outer rotor with at least some of said openings in said outer rotor being substantially aligned with corresponding ones of said openings in said Coriolis rotor;
• rotating both said outer rotor and said Coriolis rotor about said center axis of rotation using energy derived from said fluid while said fluid is extended through said openings of said Coriolis rotor and said outer rotor;
• wherein said fluid is extended by said rotors to a fluid outlet from which said fluid is discharged from said Coriolis flowmeter;
• said Coriolis rotor assuming an angular offset from said outer rotor about said center axis of rotation in response to Coriolis forces generated by said fluid extension and to the concurrent rotation of said outer rotor and said Coriolis rotor;
• generating output signals indicative of the magnitude of said angular offset;
• and
• deriving the mass flow rate of said flowing fluid in response to said generation of output signals.