Flow meter

• US 4,249,164 A
• Filed: 05/14/1979
• Issued: 02/03/1981
• Est. Priority Date: 05/14/1979
• Status: Expired due to Term

• Current Assignee: Vincent V. Tivy
• Original Assignee: Vincent V. Tivy
• Inventors: Tivy, Vincent V.
• Primary Examiner(s): Robinson, Thomas A.
• Application Number:
  US06/038,926
• Time in Patent Office: 631 Days
• Field of Search: 340/611, 340/191, 73/3, 73/211, 73/194 R, 73/194 E, 73/194 M, 73/205 R, 73/205 D
• US Class Current: 340/870.3
• CPC Class Codes: G01F 1/363 with electrical or electro-mechanical indication G01F1/37 and G01F1/38 take precedence
• CPC Class Codes: G01F 1/42 Orifices or nozzles

Abstract

A delta-P transmitter generating a signal corresponding to the differential pressure produced by a primary element installed in a conduit through which a fluid flows, comprising the primary element and a transducer implanted in the primary element to generate a signal corresponding to the differential pressure with which may be combined the signals generated by a temperature transducer and/or an absolute pressure transducer to generate an output signal corresponding to the weight or mass rate of fluid flow.

Claims

1. A delta-P transmitter for producing an output signal varying in functional relationship with the rate of fluid flow through a conduit, comprising, a primary element consisting of a rigid disk for installation in the conduit and provided with an orifice for the flow of fluid therethrough producing a differential pressure between the inlet and outlet sides of said disk varying in functional relation to the rate of fluid flow, a first aperture between the inlet and outlet sides of said disk, a first flexure diaphragm sealing said aperture flexing in proportion to said differential pressure and a transducer operatively connected to said diaphragm generating an output signal proportional to the flexing of said diaphragm.

2. A delta-P transmitter as set forth in claim 1 further including a hermetically sealed liquid filler chamber comprising said first and a second flexure diaphragm secured to and separated by a supporting rim implanted in said first aperture and said transducer being mounted within said chamber responsive to the flexing of said diaphragms in accordance with changes in said differential pressure.

3. A delta-P transmitter as set forth in claim 1 wherein said transducer is a strain gauge.

4. A delta-P transmitter as set forth in claim 1 further including a temperature transducer implanted in said primary element for producing an output signal proportional to the temperature of the fluid.

5. A delta-P transmitter as set forth in claim 1 further including an absolute pressure transducer implanted in said primary element producing an output signal proportional to the absolute pressure of the fluid.

6. A delta-P transmitter as set forth in claim 1 wherein said primary element is provided with a second aperture further including a duplex absolute pressure transducer comprising an evacuated chamber implanted in said second aperture having a first transducer responsive to the pressure on the inlet side of said primary element for producing an output signal proportional to the absolute pressure on the inlet side of said primary element and a second transducer responsive to the pressure on the outlet side of said primary element for producing an output signal proportional to the absolute pressure on the outlet side of said primary element.

7. In combination with a delta-P transmitter as set forth in claim 6 further including means responsive to the output signals of said duplex absolute pressure transducer generating an output signal proportional to the difference between said signals and means generating an alarm signal when said output signal exceeds a predetermined value.

8. A delta-P transmitter as set forth in claim 1 wherein said transducer comprises a variable capacitor having a stationary plate and a cooperating flexure diaphragm movable toward and away from said stationary plate in accordance with changes in said differential pressure.

9. A delta-P transmitter as set forth in claim 1 further including a wireway for transmitting said signal to a receiving device comprising a plurality of conductors packed in an insulating material hermetically sealed in a metal sheath implanted in said primary element.

10. In combination with a delta-P transmitter as set forth in claim 1 wherein said output signal varies in non-linear relationship to the weight rate of fluid flow at a predetermined density of the fluid, further including means generating a second signal corresponding to changes in the density of the fluid and computer means responsive to said signals generating a second output signal linearly proportional to the weight rate of fluid flow through said conduit.