Flowmeters

Claim 2

A flowmeter for measuring the rate of flow of a fluid comprising a housing having a substantially vertical passage formed with at least a cylindrical section and a divergent section through which said fluid may be caused to flow upwardly, and a rotor in said passage for interaction with and support by fluid flowing upwardly through said passage, which rotor comprises a conically-shaped fairing pointing axially upstream immediately upstream of, and defining with the walls of said passage a convergent passage to, an axial flow turbine part which is positioned to run at least in part within said cylindrical section of said passage, said fairing and turbine parts being integral and coaxial with a tail part which is downstream from said turbine part and rotatable within said divergent section of said passage, the maximum diameter of said tail part being greater than the diameter of said cylindrical section.

Claim 3

A flowmeter according to claim 1, wherein said tail part has a substantially frusto-conical surface against which the upwardly flowing fluid impinges.

Claim 4

A flowmeter according to claim 1, wherein said turbine part is provided with a plurality of substantially helical vanes.

Claim 5

A flowmeter according to claim 1, wherein said turbine part is provided with a plurality of axial vanes and wherein there are provided upstream of said rotor a plurality of fixed helical vanes.

Claim 6

A flowmeter for measuring the rate of flow of a fluid comprising a housing having a chamber therein of circular cross-section, the axis of which is disposed substantially vertically and through which fluid can be passed upWardly, said chamber including a substantially cylindrical lower chamber portion, an upper chamber portion whose diameter is larger than that of said lower chamber portion and a divergent portion between and linking said lower and upper chamber portions, a rotor in said chamber for interaction with and support by fluid passing upwardly through said chamber, and means for detecting the rate of rotation of said rotor, said rotor having a substantially conical downwardly pointing fairing, a plurality of vanes for interaction with said fluid and a tail part, said vanes being between said fairing and said tail part and the maximum diameter of said tail part being greater than the diameter of said lower chamber portion, whereby, when fluid is passed upwardly through said chamber, said rotor is supported by the moving fluid and is rotated by interaction of the moving fluid with said vanes at a rate in dependence on the rate of fluid flow, said vanes being arranged to run at least in part within said lower chamber portion.

Claim 7

A flowmeter for measuring the rate of flow of a fluid comprising a housing having a chamber therein of circular cross-section, the axis of which is disposed substantially vertically and through which fluid can be passed upWardly, said chamber including a substantially cylindrical lower chamber portion, an upper chamber portion whose diameter is larger than that of said lower chamber portion and a divergent portion between and linking said lower and upper chamber portions, a rotor in said chamber for interaction with and support by fluid passing upwardly through said chamber, and means for detecting the rate of rotation of said rotor, said rotor having a substantially conical downwardly pointing fairing, a plurality of vanes for interaction with said fluid and a tail part, said vanes being between said fairing and said tail part and the maximum diameter of said tail part being greater than the diameter of said lower chamber portion, whereby, when fluid is passed upwardly through said chamber, said rotor is supported by the moving fluid and is rotated by interaction of the moving fluid with said vanes at a rate in dependence on the rate of fluid flow, said vanes being arranged to run at least in part within said lower chamber portion.

Claim 8

A flowmeter according to claim 5, wherein said tail part includes a substantially frusto-conical surface against which said upwardly flowing fluid impinges.

Claim 9

A flowmeter according to claim 5, wherein said vanes are substantially helical.

Claim 10

A flowmeter according to claim 5, wherein said vanes are axial and where there are further provided a plurality of fixed substantially helical vanes in said lower chamber portion upstream of said rotor.