CONVENIENT ULTRASONIC INSPECTION DEVICE

• US 20070084290A1
• Filed: 12/07/2006
• Published: 04/19/2007
• Est. Priority Date: 06/21/2004
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Uyehara, Clyde, Kollgaard, Jeffrey, Fetzer, Barry
• Granted Patent: US 7,562,576 B2
• Time in Patent Office: Days
• US Class Current: 73/627
• CPC Class Codes: G01N 2291/0231 Composite or layered materials
• CPC Class Codes: G01N 2291/048 Transmission, i.e. analysed material between transmitter and receiver
• CPC Class Codes: G01N 29/0645 Display representation or displayed parameters, e.g. A-, B- or C-Scan
• CPC Class Codes: G01N 29/30 Arrangements for calibrating or comparing, e.g. with standard objects

Abstract

An ultrasonic transducer device is pressed against the front surface of a structure, emits an ultrasonic pulse into the structure, and detects an echo profile from the structure. An indicator is activated if the echo profile includes a return pulse that at least is received from between the front surface and the back surface of the structure. An ultrasonic transducer device includes an ultrasonic transducer and a coupling element coupled to the transducer for disposition between the transducer and a surface of a structure. The coupling element serves as a delay line that allows time for quiescence in the transducer so that return pulses from shallow depths can be detected. The ultrasonic transducer is activated when multiple switches are pressed against a surface thus assuring both firm coupling and perpendicular disposition of the acoustic axis of the transducer relative to the surface.

Claims

1. A method of testing a structure, the method comprising:

providing a structure having a front surface and a back surface;

pressing an ultrasonic transducer device against the front surface of the structure;

emitting an ultrasonic pulse into the structure;

detecting an echo profile from the structure; and

activating an indicator if the echo profile includes a return pulse that at least is received from between the front surface and the back surface.

2. A method according to claim 1, wherein pressing an ultrasonic transducer device against the front surface of the structure comprises pressing a coupling element coupled to an ultrasonic transducer into contact with the front surface.

3. A method according to claim 2, wherein the structure has a specific acoustic impedance, wherein the coupling element comprises a material having a specific acoustic impedance that approximately matches the specific acoustic impedance of the structure, and wherein pressing a coupling element coupled to an ultrasonic transducer into contact with the front surface comprises dry-coupling the ultrasonic transducer device to the front surface.

4. A method according to claim 1, wherein pressing an ultrasonic transducer device against the front surface of the structure comprises pressing a switch attached to the ultrasonic transducer device against the front surface.

5. A method according to claim 4, wherein pressing the switch against the front surface causes the ultrasonic transducer device to emit the ultrasonic pulse into the structure.

6. A method according to claim 1, wherein pressing an ultrasonic transducer device against the front surface of the structure comprises simultaneously pressing multiple switches attached to the ultrasonic transducer device against the front surface.

7. A method according to claim 6, wherein the multiple switches partially surround an axis passing through the ultrasonic transducer device.

8. A method according to claim 7, wherein the axis passing through the ultrasonic transducer device comprises an acoustic axis of the ultrasonic transducer device, and wherein simultaneously pressing multiple switches attached to the ultrasonic transducer device against the front surface comprises directing the acoustic axis of the ultrasonic transducer device to be perpendicular to the surface.

9. A method according to claim 1, wherein pressing an ultrasonic transducer device against the front surface of the structure comprises pressing the ultrasonic transducer device against a portion of the front surface, the portion being near an impact site of the front surface.

10. A method according to claim 9, further comprising pressing the ultrasonic transducer device against multiple portions of the front surface, the multiple portions partially surrounding an impact site of the front surface.

11. A method according to claim 1, wherein activating an indicator if the echo profile includes a return pulse that at least is received from between the front surface and the back surface comprises activating an indicator if the echo profile includes a return pulse that at least occurs before an expected time of a return pulse from the back surface.

12. A method according to claim 1, wherein activating an indicator if the echo profile includes a return pulse that at least is received from between the front surface and the back surface comprises automatically activating an indicator if the echo profile includes a return pulse that at least exhibits a time of flight of duration:

greater than a time of flight corresponding to the front surface; and

less than a predetermined time of flight corresponding to a predetermined depth defined between the front surface and the back surface.

13. A method according to claim 12, further comprising automatically activating an indicator that indicates no damage if the echo profile does not include a return pulse received from between the front surface and the predetermined depth.

14. A method according to claim 1, wherein activating an indicator if the echo profile includes a return pulse that at least is received from between the front surface and the back surface comprises automatically activating an indicator if the echo profile includes a return pulse that at least exhibits:

a time of flight of less duration than a predetermined time of flight corresponding to a predetermined depth defined between the front surface and the back surface; and

an amplitude exceeding a predetermined threshold.

15. A method according to claim 14, further comprising, once an indicator is activated, emitting additional ultrasonic pulses, detecting corresponding additional echo profiles, and continuously activating the indicator as long as detected echo profiles include return pulses that at least exhibit:

times of flight of less durations than the predetermined time of flight; and

amplitudes exceeding the predetermined threshold.

16. A diagnostic apparatus for detecting damages in a structure, the apparatus comprising:

an ultrasonic transducer device configured to be pressed against a structure, the structure having a front surface and a back surface, the ultrasonic transducer device being further configured to emit ultrasonic pulses into the structure through the front surface and detect echo profiles from the structure through the front surface;

an indicator; and

an electronic device configured to activate the indicator if the ultrasonic transducer device detects an echo profile that includes a return pulse received from between the front surface and the back surface.

17. A diagnostic apparatus for inspecting a structure through a surface of the structure, the apparatus comprising:

an ultrasonic transducer device configured to emit ultrasonic pulses and detect return pulses;

an indicator; and

an electronic device disposed in electronic communication with each of the ultrasonic transducer device and the indicator, the electronic device configured to automatically activate the indicator if the ultrasonic transducer device detects a return pulse that at least exhibits a time of flight of less duration than a predetermined time of flight.

18. A diagnostic apparatus according to claim 17, further comprising an activator assembly attached to the ultrasonic transducer device, the activator assembly configured to permit activation of the ultrasonic transducer device when the ultrasonic transducer device is pressed against a surface.

19. A diagnostic apparatus according to claim 18, wherein the activator assembly comprises multiple switches configured to permit activation of the ultrasonic transducer device when all of the multiple switches are actuated simultaneously, wherein the activator assembly is constructed such that all of the multiple switches are simultaneously actuated when the ultrasonic transducer device is pressed against a surface.

20. A diagnostic apparatus according to claim 19, wherein the multiple switches at least partially surround an axis passing through the ultrasonic transducer device.

21. A diagnostic apparatus according to claim 17, wherein the ultrasonic transducer device comprises an ultrasonic transducer and a coupling element coupled to the transducer for disposition between the transducer and a surface of a structure.

22. A diagnostic apparatus according to claim 21, further comprising multiple switches attached to the ultrasonic transducer device and configured to permit activation of the ultrasonic transducer when all of the multiple switches are actuated simultaneously by pressing the coupling element against a surface of a structure.

23. A diagnostic apparatus according to claim 17, wherein the electronic device is configured to automatically activate the indicator if the ultrasonic transducer device detects a return pulse that at least exhibits a time of flight of duration greater than a first predetermined time of flight and less than a second predetermined time of flight.

24. A diagnostic apparatus according to claim 23, wherein the ultrasonic transducer device comprises an ultrasonic transducer and a coupling element for disposition between the transducer and a surface of a structure, wherein the coupling element has a proximal end coupled to the transducer and a distal end for pressing against a surface, and wherein the first predetermined time of flight corresponds approximately to the distal end of the coupling element.

25. A diagnostic apparatus according to claim 17, wherein the electronic device is configured to automatically activate the indicator if the ultrasonic transducer device detects a return pulse that at least exhibits:

a time of flight of duration greater than a first predetermined time of flight and less than a second predetermined time of flight; and

an amplitude exceeding a predetermined threshold.

26. A diagnostic apparatus according to claim 25, wherein the electronic device is configured to, once the indicator is activated, continuously activate the indicator as long as the ultrasonic transducer device detects return pulses that at least exhibit:

times of flight of durations greater than the first predetermined time of flight and less than the second predetermined time of flight; and

amplitudes exceeding the predetermined threshold.