Turbine-type volumetric flowmeters

Claim 2

A volumetric fluid flowmeter comprising a body through which flows the fluid, the flow rate of which is to be measured, a measuring turbine mounted in the body so as to be rotated by the flowing fluid about an axis parallel to the direction of fluid flow; means for detecting the speed of rotation of the measuring turbine; means for annulling any non-axial component of the absolute velocity of the fluid present at the measuring turbine, said means comprising a detector element for detecting any said non-axial component of the absolute velocity of the fluid at its exit from the measuring turbine; a corrector element acting on the speed of rotation of the turbine; a servo-control device cOnnecting said detector element to said corrector element, said detector element comprising a plane blade radially mounted in the body parallel to the axial flow of the fluid so as to be free to bend; and strain gauge means for sensing said bending and for delivering an error signal to the servo-control device whereby such bending gives a measure of the non-axial component of the absolute exit velocity of the fluid.

Claim 3

A flowmeter according to claim 1, wherein the said corrector element comprises A flap pivotally mounted upstream of the measuring turbine; And a motor/reducing-gear group acting on the position of said flap.

Claim 4

A volumetric fluid flow meter comprising a body through which flows the fluid the flow rate of which is to be measured; a measuring turbine mounted in the body so as to be rotated by the flowing fluid about an axis parallel to the direction of fluid flow; means for detecting the speed of rotation of the measuring turbine; and means for annulling any non-axial component of the absolute velocity of the fluid present at the measuring turbine, said means comprising a detector element for detecting any said non-axial component of the absolute velocity of the fluid at its exit form the measuring turbine; a corrector element acting on the speed of rotation of the turbine; and a servo-control device connecting the detector element to the corrector element and wherein said detector element comprising a second turbine mounted in the body coaxially with, and downstream of, the measuring turbine, the second turbine being provided with blades of axial direction whereby its rotation is a measure of the non-axial component of the said absolute exit velocity of the fluid, and a transducer member for translating the rotation of said second turbine into an error signal for the servo-control device wherein the transducer member is a photo-electric detector of rotation.

Claim 5

A volumetric fluid flow meter comprising a body through which flows the fluid the flow rate of which is to be measured; a measuring turbine mounted in the body so as to be rotated by the flowing fluid about an axis parallel to the direction of fluid flow; means for detecting the speed of rotation of the measuring turbine; and means for annulling any non-axial component of the absolute velocity of the fluid present at the measuring turbine, said means comprising a detector element for detecting any said non-axial component of the absolute velocity of the fluid at its exit form the measuring turbine; a corrector element acting on the speed of rotation of the turbine; and a servo-control device connecting the detector element to the corrector element and wherein said detector element comprising a second turbine mounted in the body coaxially with, and downstream of, the measuring turbine, the second turbine being provided with blades of axial direction whereby its rotation is a measure of the non-axial component of the said absolute exit velocity of the fluid, and a transducer member for translating the rotation of said second turbine into an error signal for the servo-control device wherein the transducer member is a photo-electric detector of rotation.

Claim 6

Flowmeter according to claim 3, wherein said corrector element comprises a motor/reducing-gear group driving the measuring turbine in rotation.

Claim 7

Flowmeter according to claim 3, wherein said servo-control device comprises a frequency-to-voltage converter and an amplifier.

Claim 8

Flowmeter according to claim 5, wherein said corrector element comprises a motor/reducing-gear group driving the measuring turbine in rotation.