FLUID SENSOR WITH MECHANICAL POSITIONAL FEEDBACK

• US 20070295104A1
• Filed: 06/07/2007
• Published: 12/27/2007
• Est. Priority Date: 06/12/2006
• Status: Active Grant

• Current Assignee: Precision Pumping Systems Incorporated
• Original Assignee: Precision Pumping Systems Incorporated
• Inventors: ELLEGOOD, PAUL L.
• Granted Patent: US 7,921,726 B2
• Time in Patent Office: Days
• US Class Current: 73/861.79
• CPC Class Codes: G01F 1/28 by drag-force, e.g. vane type or impact flowmeter
• CPC Class Codes: G01F 1/38 the pressure or differential pressure being measured by means of a movable element, e.g. diaphragm, piston, Bourdon tube or flexible capsule
• CPC Class Codes: G01F 1/383 with electrical or electro-mechanical indication
• CPC Class Codes: G01F 23/68 using electrically actuated indicating means
• CPC Class Codes: G01P 5/04 using deflection of baffle-plates

Abstract

A fluid detection device is herein disclosed as including a sensor mount, a flexible deflection sensor rigidly connected to the sensor mount and a stiffener. The stiffener is arranged together with the flexible deflection sensor such that the flexible deflection sensor is preconfigured to deform in a predetermined manner when the fluid detection device is exposed to a fluid. An amount of the deformation of the flexible deflection sensor determines a property of the fluid.

A pressure sensing apparatus is herein disclosed as including a rigid perimeter, a flexible membrane forming a surface area bounded by the perimeter, and a sensing means in communication with the flexible membrane. The flexible membrane is configured to elastically deform when a pressure force is exerted on the surface area, and the sensing means is configured to measure an amount of deformation of the flexible membrane.

Claims

1. A fluid detection device comprising a flexible deflection sensor configured to deform in a predetermined manner when the fluid detection device is exposed to a fluid, where an amount of the deformation of the flexible deflection sensor determines a property of the fluid.

2. The fluid detection device according to claim 1 where the amount deformation results in an electrical signal that can be correlated with a magnitude of the fluid property.

3. The fluid detection device according to claim 2 including a first end of the flexible deflection sensor connected to the sensor mount and a second end of the flexible deflection sensor configured to move in a predetermined arc, where the fluid property is a flow rate.

4. The fluid detection device according to claim 2 including a sensor membrane configured to deform under pressure, where the fluid property is a pressure of the fluid.

5. The fluid detection device according to claim 2 where the flexible deflection sensor is configured to result in a larger electric signal when the deformation occurs at one end of the flexible deflection sensor as compared with an electrical signal resulting from a deformation at a second end, and where the fluid property is a fluid level.

6. A fluid sensing system comprising:

a sensor port;

a sensor including a first end mounted to the sensor port and a second end configured to deflect in a predetermined arc when exposed to a fluid force, where an electric signal is propagated through the sensor during operation of the fluid sensing system; and

a stiffening agent located adjacent the sensor which provides a preconfigured resistance to a deflection of the second end of the sensor, where a characteristic of the electrical signal that varies with an amount of deflection of the sensor is measured to infer a property of the fluid force.

7. The fluid sensing system according to claim 6 where the stiffening agent may be configured to provide a different amount of resistance to the deflection of the sensor for a given fluid force to compensate for different fluid conditions.

8. The fluid sensing system according to claim 7 where the sensor deflects if a fluid level is above a threshold level, and does not deflect if the fluid level is below the threshold level.

9. The fluid sensing system according to claim 7 where the sensor deflects from the fluid force resulting from a fluid flowing through a pipe.

10. The fluid sensing system according to claim 6 including a sail pivotably connected to the sensor port, where the sensor deflects as a result of the fluid force acting on the sail and causing it to pivot in a direction of a fluid flow.

11. The fluid sensing system according to claim 6 where the stiffening agent is located adjacent the second end of the sensor and includes a counterweight.

12. The fluid sensing system according to claim 11 where the counterweight includes a flow-through hole to reduce an amount of fluid turbulence.

13. The fluid sensing system according to claim 11 where the counterweight urges the sensor to a vertical orientation in reduced fluid force conditions.

14. The fluid sensing system according to claim 6 where the sensor is configured to distinguish a fluid flow in a first direction from a fluid flow in a second direction opposite the first direction.

15. The fluid sensing system according to claim 15 where the sensor is configured to measure a flow rate in both the first and second directions.

16. A pressure sensing apparatus comprising:

a rigid perimeter;

a flexible membrane forming a surface area bounded by the perimeter; and

a sensing means in communication with the flexible membrane, where the flexible membrane is configured to elastically deform when a pressure force is exerted on the surface area and the sensing means is configured to measure an amount of deformation of the flexible membrane.

17. The pressure sensing apparatus according to claim 16 where the sensing means includes a flexible sensor that is configured to deform in unison with the flexible membrane.

18. The pressure sensing apparatus according to claim 17 where the flexible sensor overlays on the flexible membrane to form a circuit for carrying an electrical signal.

19. The pressure sensing apparatus according to claim 18 where the deformation of the flexible membrane causes a characteristic of the electrical signal to vary according to the amount of deformation, and where the characteristic of the electric signal correlates to a magnitude of the pressure force.

20. The pressure sensing apparatus according to claim 17 where the flexible sensor includes a first end connected to an approximate center of the flexible membrane, and where the deformation of the flexible membrane causes the first end to move towards a second end of the flexible sensor to vary a characteristic of an electrical signal that is being transmitted through the flexible sensor in order to determine a magnitude of the pressure force.