Phase controlled variable angle ultrasonic flow meter

• US 9,494,454 B2
• Filed: 04/17/2014
• Issued: 11/15/2016
• Est. Priority Date: 12/06/2013
• Status: Expired due to Fees

• Current Assignee: Joseph Baumoel
• Original Assignee: Joseph Baumoel
• Inventors: Baumoel, Joseph
• Primary Examiner(s): Martin, Laura
• Assistant Examiner(s): MILLER, ROSE MARY
• Application Number:
  US14/255,408
• Publication Number:
  US 20150160053A1
• Time in Patent Office: 943 Days
• Field of Search: 736/41, 736/28, 310/354, 310/355, 310/340, 310/348, 310/334, 310/336, 310/337
• US Class Current: 1/1
• CPC Class Codes: B06B 1/0215 for generating pulses, e.g. bursts of oscillations, envelopes
• CPC Class Codes: B06B 1/0607 using multiple elements B06B1/064 and B06B1/0688 take precedence
• CPC Class Codes: G01F 1/662 Constructional details
• CPC Class Codes: G01F 1/667 Arrangements of transducers for ultrasonic flowmeters; Circuits for operating ultrasonic flowmeters
• CPC Class Codes: G01F 1/668 Compensating or correcting for variations in velocity of sound
• CPC Class Codes: G10K 11/346 using phase variation

Abstract

An ultrasonic transducer includes: a plurality of segment electrodes located on a surface of a single piezoelectric element; a pulse generator configured to generate a pulse signal having pulses of a certain frequency; and a control circuit that sequentially activates the segment electrodes using the pulse signal to cause the element to emit a sonic signal, where a controlled delay time between activation of each segment electrode varies the emission angle of the sonic signal so as to compensate for angle changes caused by either changes in Beam refraction or due to Beam Blowing caused by high flow velocity.

Claims

1. An ultrasonic transducer system comprising:

a first ultrasonic transducer comprising a plurality of first segment electrodes located on a surface of a single first piezoelectric element;

a second ultrasonic transducer comprising a plurality of second segment electrodes located on a surface of a single second piezoelectric element;

a pulse generator configured to generate a pulse signal that comprises pulses of a transmit frequency; and

a control circuit that sequentially activates the first segment electrodes using the pulse signal to cause the first piezoelectric element to emit a first sonic signal, where a delay time of a first value between activation of each successive first segment electrode controls a phase velocity of the first sonic signal, and the angle of emission of the first sonic signal,

wherein the control circuit is configured to change a value of the delay time to a second value different from the first value when the angle of emission is determined to be out of alignment with a reference angle,

wherein the angle of emission is determined to be out of alignment with the reference angle, when a characteristic of a second sonic signal transmitted by the second ultrasonic transducer in response to the emitted first sonic signal deviates from a reference characteristic.

2. The ultrasonic transducer system of claim 1, wherein the first segment electrodes are bonded to the surface of the single first piezoelectric element and the second segment electrodes are bonded to the surface of the single second piezoelectric element.

3. The ultrasonic transducer system of claim 1, further comprising a clamp that enables the ultrasonic transducer system to be clamped around a spool of pipe.

4. The ultrasonic transducer system of claim 3, wherein the clamp comprises a sonically absorptive plastic.

5. The ultrasonic transducer system of claim 1, further comprising a sonically conductive and dissipative plastic surrounding the piezoelectric element.

6. The ultrasonic transducer system of claim 1, wherein the control circuit further comprises a transceiver configured to wirelessly transmit data based on the second sonic signal sensed by the first transducer.

7. The ultrasonic transducer of claim 1, wherein one of the piezoelectric elements is sealed within a metal tube.

8. The ultrasonic transducer system of claim 7, wherein the tube includes a hollow wiring cavity that enables wires to be connected to the segment electrodes of the one piezoelectric element.

9. The ultrasonic transducer system of claim 7, wherein a front face of the metal tube has a ¼

wavelength plastic coating.

10. The ultrasonic transducer system of claim 1, where the first segment electrodes are each spaced apart from one another a same distance and the second segment electrodes are spaced apart from one another a same distance.

11. The ultrasonic transducer system of claim 10, wherein the phase velocity is the delay time divided by the distance.

12. The ultrasonic transducer system of claim 1, wherein the control circuit is configured to continually adjust the delay time when it determines the angle of emission is out of alignment with the reference angle until the adjustments result in the angle of emission being in alignment with the reference angle.

13. The ultrasonic transducer system of claim 1, wherein the reference characteristic is based on a third sonic signal received by the first ultrasonic transducer from the second ultrasonic transducer prior to emission of the first sonic signal.

14. The ultrasonic transducer system of claim 13, wherein the reference characteristic is an amplitude, a phase, or an energy signature of the third signal relative to a fixed reference.

15. An ultrasonic transducer system comprising:

a first ultrasonic transducer comprising a plurality of first segment electrodes located on a surface of a single first piezoelectric element;

a second ultrasonic transducer comprising a plurality of second segment electrodes located on a surface of a single second piezoelectric element;

a pulse generator configured to generate a pulse signal that comprises pulses of a transmit frequency; and

a control circuit that sequentially activates the first segment electrodes using the pulse signal to cause the piezoelectric element to emit a first sonic signal, where a delay time of a first value between activation of each successive first segment electrode controls phase velocity of the sonic signal, and the angle of emission of the first sonic signal,

wherein the control circuit changes the transmit frequency of the pulse generator to a different frequency when it determines that the angle of emission is out of alignment with a reference angle,

wherein the angle of emission is determined to be out of alignment with the reference angle, when a characteristic of a second sonic signal transmitted by the second ultrasonic transducer in response to the emitted first sonic signal deviates from a reference characteristic.

16. The ultrasonic transducer system of claim 15, wherein the first segment electrodes are bonded to the surface of the single first piezoelectric element and the second segment electrodes are bonded to the surface of the single second piezoelectric element.

17. The ultrasonic transducer system of claim 15, wherein the reference characteristic is based on a third sonic signal received by the first ultrasonic transducer from the second ultrasonic transducer prior to emission of the first sonic signal.

18. The ultrasonic transducer system of claim 17, wherein the reference characteristic is an amplitude, a phase, or an energy signature of the third signal relative to a fixed reference.

19. An ultrasonic transducer comprising:

a plurality of segment electrodes located on a surface of a single piezoelectric element;

a pulse generator configured to generate a pulse signal that comprises pulses of a transmit frequency; and

a control circuit that sequentially activates the segment electrodes using the pulse signal to cause the piezoelectric element to emit a sonic signal, where a delay time between activation of each successive segment electrode controls phase velocity of the sonic signal, and the angle of emission of the sonic signal,

wherein after the control circuit sequentially activates the segment electrodes using the pulse signal, the control circuit applies a dampening pulse signal to the segment electrodes to dampen the emitted sonic signal.

20. The ultrasonic transducer of claim 19, wherein the segment electrodes are bonded to the surface of the single piezoelectric element.