Thermal flowmeter
AssigneeCDI Meters, Inc.
InventorRoger Dennison
Life of this patent
Estimating the term…
Abstract
A flowmeter of the thermal type, having a heated flow-sensing probe and a temperature-sensing reference probe, in which the flow is passed through nozzles to form two jets and those jets are directed at the heated portion of the heated probe and the temperature-sensing portion of the reference probe, while flow around the supporting portion of the heated probe is minimized. Such a flowmeter allows low gas flows to be measured without the use of capillary elements that are subject to plugging and can create unwanted pressure drops.
Claims7
A flowmeter of the thermal type, where the flowmeter is adapted to have fluid passed through it along a fluid flow path, the flowmeter comprising:
- a body that defines the entire fluid flow path through the flowmeter;
- a baffle in the body and arranged such that it entirely blocks the fluid flow path, the baffle defining first and second chambers in the body arranged serially relative to the fluid flow, the baffle having only first and second openings, the first and second openings arranged to pass the entire fluid flow from the first chamber into the second chamber;
- wherein the first opening defines an inlet open to the first chamber and an outlet open to the second chamber to create a first fluid jet in the second chamber;
- wherein the second opening defines an inlet open to the first chamber and an outlet open to the second chamber, to create a second fluid jet in the second chamber;
- a heated probe in the second chamber, with a heated portion immediately downstream of the first opening and arranged such that the heated portion is in the first jet;
- and
- a reference probe in the second chamber, with a temperature-sensing portion immediately downstream of the second opening and arranged such that the temperature-sensing portion is in the second jet.
Dependencies are inferred from the claim text.