# US 5,343,764 A · Coriolis-type mass flowmeter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,343,764 A - Document ID: US5343764A - Status: Granted - Kind: A - Application number: 07/879,156 - Filed: 1992-04-30 - Granted: 1994-09-06 - Earliest claimed: 1986-10-28 - Assignees: The Foxboro Company - Inventors: Wade M. Mattar; Duane T. Thompson; Joseph P. DeCarlo; Yousif Hussain; Gordon W. Chitty - Web page: https://patentgrep.com/patent/US5343764A ## CPC - G01F 1/8413: {means for influencing the flowmeter's motional or vibrational behaviour, e.g., conduit support or fixing means, or conduit attachments} - G01F 1/8431: {electronic circuits} - G01F 1/8436: {signal processing} - G01F 1/8486: {with multiple measuring conduits} - G01F: MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME ## Abstract A rigid central manifold block defines a coaxial inlet and outlet of the flowmeter and supports at least one continuous conduit loop substantially encircling the block and having its inlet and outlet ends closely spaced and rigidly connected to the block. Preferably, the loop includes a straight section perpendicular to the inlet and outlet ends. Dual drive means are preferably provided for oscillating the straight section back and forth about its perpendicular bisector and complementary position detectors employed at or near the opposite ends of the straight section, preferably at the same location as the drive units, provide readouts which are combined algebraically and synchronously demodulated to yield a Coriolis-related output indicative of mass flow. Preferably, a second loop, identical and parallel to the first, is supported by the same block. The block is channeled to serve as a manifold and interchangeable manifolds are disclosed for series and parallel flow through the two loops, respectively. The plane of the loop or loops can be oriented perpendicular or parallel (in line) to the process line. ## Claims ### Claim 1 A dual drive Coriolis-type mass flowmeter, comprising a support, a continuous loop of conduit solidly mounted at its inlet and outlet ends to the support, a pair of drivers acting on said loop at different respective points along the loop for oscillating said loop about an oscillation axis between said points, and a pair of sensors for measuring the magnitude of Coriolis forces arising as a result of mass flow in the portion of said conduit undergoing oscillatory motion, said sensors being juxtaposed respectively with said drivers. ### Claim 2 (depends on 1) The flowmeter of claim 1, wherein said respective points are equidistant from an axis of symmetry of said loop. ### Claim 3 (depends on 1) The flowmeter of claim 1, wherein the portion of said loop between said pair of drivers is a substantially straight section. ### Claim 4 (depends on 3) The flowmeter of claim 3, wherein said drivers are at opposite ends of said straight section of said conduit. ### Claim 5 (depends on 3) The flowmeter of claim 3, further comprising means for controlling said drivers so that said straight section therebetween is oscillated about its perpendicular bisector. ### Claim 6 (depends on 3) The flowmeter of claim 3, further comprising a coaxial inlet and outlet of the flowmeter, said straight section being nonparallel to the inlet/outlet axis. ### Claim 7 (depends on 3) The flowmeter of claim 3, further comprising a coaxial inlet and outlet of the flowmeter, said straight section being parallel to the inlet/outlet axis. ### Claim 8 (depends on 3) The flowmeter of claim 3, wherein the ends of said loop connected to said support are parallel and perpendicular to said straight section, whereby oscillation of said straight section is accommodated by torsional vibration of said parallel sections. ### Claim 9 (depends on 1) The flowmeter of claim 1, further comprising another support and another continuous conduit loop solidly mounted at its inlet and outlet ends to said other support and other drivers for oscillating said other loop about an oscillation axis, and means corresponding to said second loop for measuring the magnitude of coriolis forces therein, arising as a result of mass flow in said second conduit while undergoing oscillatory motion. ### Claim 10 (depends on 9) The flowmeter of claim 9, wherein said conduit loops are parallel. ### Claim 11 (depends on 10) The flowmeter of claim 10, wherein said conduit loops are planar, parallel and substantially identical in configuration. ### Claim 12 (depends on 11) The flowmeter of claim 11, wherein the portions of said loops between said drivers are straight sections. ### Claim 13 (depends on 12) The flowmeter of claim 12, further comprising means for controlling both of said drivers so as to induce oscillatory motion of said straight sections about respective parallel perpendicular bisectors. ### Claim 14 (depends on 13) The flowmeter of claim 13, wherein the ends of each loop attached to the respective support are all parallel and perpendicular to the straight sections. ### Claim 15 (depends on 9) The flowmeter of claim 9, wherein said other drivers includes a second pair of drivers acting on different respective points along the other loop. ### Claim 16 (depends on 15) The flowmeter of claim 15, wherein said respective points on the other loop are equidistant from an axis of symmetry of the other loop. ### Claim 17 (depends on 15) The flowmeter of claim 15, wherein said loops are parallel and substantially identical in configuration and said respective points along each loop are at the same corresponding positions on each loop. ### Claim 18 (depends on 17) The flowmeter of claim 17, wherein corresponding ones of said respective points for both loops are equidistant from a plane of symmetry for both loops. ### Claim 19 A coriolis-type mass flowmeter comprising a section of conduit, a pair of drivers arranged near opposite ends of said section for oscillating said section about an axis between said drivers, and a pair of sensors arranged near opposite ends of said section for sensing the magnitude of Coriolis forces arising as result of mass flow in said section of conduit undergoing oscillatory motion. ### Claim 20 (depends on 19) The flowmeter of claim 19, wherein said sensors and drivers are juxtaposed respectively. ### Claim 21 (depends on 20) The flowmeter of claim 20, wherein said sensors are respective to a function of the displacement of the respective ends of said section. ### Claim 22 (depends on 19) The flowmeter of claim 19, further comprising a support, a substantially continuous length of conduit having inlet and outlet ends forming a continuous flow tube, an intermediate portion of said continuous conduit including said section of conduit undergoing oscillatory motion, the inlet and outlet ends of said conduit being rigidly connected to said support such that oscillation of said section of conduit about said axis by said drivers is absorbed as torsional deflection of said conduit. ### Claim 23 (depends on 22) The flowmeter of claim 22, wherein said section of conduit is a substantially straight section, and the inlet and outlet ends of said continuous conduit include a pair of legs, respectively, each rigidly connected at one end to said support, the orientation of the legs being substantially perpendicular to the straight section, said legs being parallel and proximate to said axis of oscillation of the straight section by said drivers, the oscillation of said straight section of conduit about said axis being absorbed as torsional deflection of the parallel legs. ### Claim 24 (depends on 23) The flowmeter of claim 23, wherein said legs are shorter than said straight section. ### Claim 25 (depends on 23) The flowmeter of claim 23, wherein said legs of each loop are mounted close together. ### Claim 26 A coriolis-type mass flowmeter comprising two parallel sections of conduit juxtaposed with each other in spaced relationship, a pair of driver assemblies arranged near opposite ends of said sections for oscillating both sections simultaneously in opposite directions about axes between said drivers, and a pair of sensor assemblies arranged near opposite ends of said sections for sensing the magnitude of Coriolis forces arising as result of mass flow in said sections of conduit undergoing oscillatory motion. ### Claim 27 (depends on 26) The flowmeter of claim 26, wherein said sensor assemblies are juxtaposed respectively with said driver assemblies. ### Claim 28 (depends on 27) The flowmeter of claim 27, wherein said sensor assemblies are responsive to a function of the relative displacement of the respective ends of said sections. ### Claim 29 (depends on 26) The flowmeter of claim 26, further comprising a support, two substantially continuous lengths of conduit each having inlet and outlet ends forming two substantially identical flow tubes, an intermediate portion of each of said continuous conduits including a corresponding one of said parallel sections of conduit undergoing oscillatory motion, the inlet and outlet ends of each said conduit being rigidly connected to said support such that oscillation of said sections of conduit about said axes by said drivers is absorbed as torsional deflection of the conduits. ### Claim 30 (depends on 68) The flowmeter of claim 68, wherein said sections of conduit are both substantially straight sections, and the inlet and outlet ends of each said continuous conduit include a pair of legs, respectively, each rigidly connected at one end to said support, the orientation of the legs of each conduit being substantially perpendicular to the straight section of the same conduit, said legs of each pair being parallel and proximate to said axis of oscillation of the respective straight section by said drivers, the oscillation of said straight section of each conduit about the respective one of said axes being absorbed as torsional deflection of the respective parallel legs. ### Claim 31 (depends on 30) The flowmeter of claim 30, wherein said legs are shorter than said straight section. ### Claim 32 (depends on 30) The flowmeter of claim 30, wherein said legs of each loop are mounted close together. ### Claim 33 (depends on 30) The flowmeter of claim 30, wherein said conduits exhibit matching inherent vibrational resonances like a tuning fork. ### Claim 34 A Coriolis-type mass flowmeter for measuring mass flow in a pipeline, comprising a rigid support with an inlet and an outlet adapted to be connected to the pipeline, a dual tube loop assembly including two substantially identical, parallel, closely spaced, continuous, nominally planar conduit loops connected to said support, each said loop having an intermediate elongated straight section, a pair of drivers for oscillating said loops 180.degree. out of phase with each other, said drivers arranged to act on said loops at opposite ends of each said straight section about a drive oscillation axis coinciding approximately with the perpendicular bisector of the respective straight section, the inlet and outlet ends of each loop including a pair of legs, respectively, each rigidly connected at one end to said support, the orientation of the legs of each loop being substantially perpendicular to the straight section of the same loop, said legs of each pair being parallel and proximate to the drive oscillation axis of the respective straight section, the oscillation of said straight section of each loop about its drive oscillation axis being absorbed as torsional deflection of the respective parallel legs, a pair of sensor juxtaposed respectively with said drivers at the ends of said straight sections for sensing the motion of the straight sections, and circuitry responsive to said sensors for deriving the magnitude of Coriolis forces arising as a result of mass flow in said respective loops. ### Claim 35 (depends on 34) The flowmeter of claim 34, wherein said loops exhibit matching inherent vibrational resonances like a tuning fork. ### Claim 36 (depends on 34) The flowmeter of claim 34, wherein said legs are substantially straight. ### Claim 37 (depends on 36) The flowmeter of claim 36, wherein said inlet and outlet of said support are coaxial and said straight sections are approximately perpendicular to the inlet and outlet axis. ### Claim 38 (depends on 37) The flowmeter of claim 37, wherein said loops exhibit matching inherent vibrational resonances like a tuning fork. ### Claim 39 (depends on 34) The flowmeter of claim 34, further comprising circuitry responsive to said sensors for generating complementary drive signals for said drivers. ### Claim 40 (depends on 34) The flowmeter of claim 34, wherein said legs are perpendicular to said inlet and outlet of said support. ### Claim 41 (depends on 34) The flowmeter of claim 34, wherein said legs are shorter than said straight section. ### Claim 42 (depends on 34) The flowmeter of claim 34, wherein said legs of each loop are mounted close together.