Measuring and testing – Volume or rate of flow – By measuring vibrations or acoustic energy
Patent
1995-07-10
1997-07-29
Dombroske, George M.
Measuring and testing
Volume or rate of flow
By measuring vibrations or acoustic energy
G01F 100
Patent
active
056523963
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a fluid flowmeter particularly although not exclusively of the ultrasonic axial flow type.
2. Discussion of the Background
Fluid flowmeters of the axial ultrasonic type comprise a conduit through which, in use, a fluid flows by way of inlet means and outlet means for flow rate measurement, a first transducer for transmitting signals to and receiving signals from a second transducer by way of the conduit, the second transducer being spaced from the first transducer along the conduit for transmitting signals to and receiving signals from the first transducer and means for detecting the time of flight of the signals between the transducers in order to measure the flow rate of fluid along the conduit.
A problem with fluid flowmeters of the above type is that there is a tendency for spurious signal reflections to occur at the walls of the conduit. These interfere with the actual signal or at least provide false or inaccurate time of flight readings and therefore false or inaccurate fluid flow rate measurements.
It is therefore an object of the present invention to alleviate these effects.
SUMMARY OF THE INVENTION
According to the present invention there is provided a fluid flowmeter comprising a conduit through which in use fluid flows by way of inlet means and outlet means for flow rate measurement, a first transducer for transmitting signals to and receiving signals from a second transducer by way of the conduit, the second transducer being spaced from the first transducer along the conduit for transmitting signals to and receiving signals from the first transducer, means for detecting the time of flight of the signals between the transducers in order to measure the flow rate of the fluid along the conduit and means extending along the conduit to provide for the fluid an annular flow path along which in use the signals are transmitted.
Preferably the means extending along the conduit comprises a rod which suitably tapers outwardly from its ends to form a section of maximum external diameter within the conduit.
Conveniently the rod comprises a number of interconnected sections of differing external diameters.
In one embodiment the ends of the rod are conical but in this case the rod is otherwise of constant external diameter.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention will now be particularly described with reference to the drawings in which:
FIG. 1 is a schematic side view of a first embodiment of the invention,
FIG. 2 is a schematic side view of a second embodiment of the invention,
FIG. 3 is a schematic side view of one end of a third embodiment of the invention, and
FIG. 4 is a side view of one end of an alternative arrangement for FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1 the fluid flowmeter illustrated is of the ultrasonic axial flow type and includes a straight or linear conduit 1, having first and second ends 2 and 3 in which are respectively mounted first and second transducers 4 and 5. The transducers 4 and 5 are positioned to transmit ultrasonic signals along the conduit 1 towards the other transducer and to receive such signals after transmission. The conduit I is formed with fluid inlet means 6 which in this case takes the form of two diametrically opposed inlet tubes adjacent the first end 2 of the conduit 1. Similarly the conduit 1 is formed with fluid outlet means 7 which also take the form of two diametrically opposed outlet tubes. The transducers 4 and 5 are each connected to a detector 8 for detecting the time of flight of each signal through the fluid flowing in the conduit. The detector 8 incorporates an electronic processing apparatus whereby the time of flight of a signal in one direction can be used with the time of flight of a signal in the opposite direction to compute the flow rate of the fluid along the conduit. The detector 8 may also include an indicator (not shown) in the form of a visual display showing a volume flow rate or total volume
REFERENCES:
patent: 5093810 (1992-03-01), Gill
patent: 5163331 (1992-11-01), Gill
patent: 5168762 (1992-12-01), Gill
patent: 5178018 (1993-01-01), Gill
patent: 5243863 (1993-09-01), Gill
patent: 5375099 (1994-12-01), Gill
patent: 5383369 (1995-01-01), Khuri-Yakub et al.
patent: 5461931 (1995-10-01), Gill
International Search Report, International Application No. PCT/GB94/00526, Eurpoean Patent Office Jun. 3, 1994.
Biegel Ronald
British Gas plc
Dombroske George M.
LandOfFree
Fluid flowmeter does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Fluid flowmeter, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Fluid flowmeter will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-635065