Acoustic sensing device, system and method for monitoring emissions from machinery

• US 20040050163A1
• Filed: 09/16/2002
• Published: 03/18/2004
• Est. Priority Date: 09/16/2002
• Status: Active Grant

• Current Assignee: Radialics, Inc.
• Original Assignee: Radialics, Inc.
• Inventors: Komninos, Nikolaos I.
• Granted Patent: US 6,923,063 B2
• Time in Patent Office: Days
• US Class Current: 73/587
• CPC Class Codes: G01H 1/00 Measuring characteristics of vibrations in solids by using direct conduction to the detector G01H9/00, G01H11/00 take precedence
• CPC Class Codes: G01N 2291/101 one transducer
• CPC Class Codes: G01N 29/14 using acoustic emission techniques echo of particles G01N29/046; measuring mechanical vibrations or acoustic waves in solids in general G01H1/00
• CPC Class Codes: G01N 29/4427 with stored values, e.g. threshold values
• CPC Class Codes: G01N 29/46 by spectral analysis, e.g. Fourier analysis or wavelet analysis spectral signal processing per se G06F17/14

Abstract

A device and system are provided for monitoring acoustic emissions from machinery to indicate levels of detected sound waves. Each incorporates an acoustic sensing device which broadly comprises a housing assembly constructed for removable attachment between a surface mounting region of the machinery and a measuring instrument to define a coupled state. An acoustic emissions sensor is disposed in the housing assembly'"'"'s interior to detect sound waves propagating through the surface mounting region and to produce detection signals for processing by the measuring instrument. A methodology for monitoring acoustic emissions is also provided.

Claims

1. An acoustic sensing device for use in transmitting to a measuring instrument detection signals indicative of sound wave levels detected from machinery, said acoustic sensing device comprising:

(a) a housing assembly constructed for removable attachment between a surface mounting region of the machinery and the measuring instrument to define a coupled state; and

(b) an acoustic emissions sensor disposed in an interior of said housing assembly and operative when said housing assembly is in the coupled state to detect sound waves propagating through the surface mounting region of the machinery and produce said detection signals for processing by said measuring instrument.

2. An acoustic sensing device according to claim 1 wherein said housing assembly includes a housing body constructed to directly couple to the surface mounting region of the machinery.

3. An acoustic sensing device according to claim 2 wherein said housing assembly includes a coupler for interfacing said housing assembly with the measuring instrument via an appropriate communications interface.

4. An acoustic sensing device according to claim 2 wherein acoustic emissions sensor is disposed within said an interior of said housing body, and wherein said housing assembly includes a mounting adapter for releasable attachment between the surface mounting region of the machinery and said housing body.

5. An acoustic sensing device according to claim 1 including a coupler for interfacing said housing assembly with the measuring instrument.

6. An acoustic sensing device according to claim 5 wherein said coupler is selected from a group consisting of a coaxial connector, a multi-pin connector and an MIL Type connector.

7. An acoustic sensing device according to claim 1 including a mounting adapter for indirectly coupling said housing assembly to the surface mounting region of the machinery.

8. An acoustic sensing device according to claim 7 wherein said housing assembly is adapted to threadedly engage said mounting adapter.

9. An acoustic sensing device according to claim 8 wherein said mounting adapter is adapted to threadedly engage the surface mounting region of said machinery.

10. An acoustic sensing device according to claim 8 wherein said mounting adapter is adapted to magnetically couple to the surface mounting region of the machinery.

11. An acoustic sensing device according to claim 8 wherein said mounting adapter is adapted to adhere to the surface mounting region of the machinery.

12. An acoustic sensing device according to claim 1 wherein said acoustic emissions sensor includes a piezoelectric transducer adapted upon exposure to the sound waves propagating through the surface mounting region of the machinery to mechanically stress and produce corresponding transducer signals, and conditioning circuitry for receiving said transducer signals and for producing said detection signals for processing by the measuring instrument.

13. An acoustic sensing device according to claim 10 wherein said housing assembly is electrically conductive and said conditioning circuitry is grounded to said housing assembly.

14. An acoustic sensing device according to claim 13 wherein said housing assembly is acoustically conductive.

15. An acoustic sensing device, comprising:

(a) a housing assembly including;

i. a housing body having first and second end portions;

ii. a mount disposed on said first end portion for permitting removable attachment of said housing body relative to a surface mounting region of the machinery; and

iii. a coupler disposed on said second end portion for permitting said housing body to be selectively coupled to measuring instrumentation via a communications interface; and

(b) an acoustic emissions sensor supported within said housing interior in electrical communication with said coupler, said acoustic emissions sensor operative, when the housing body is attached relative the surface mounting region and the measuring instrumentation is coupled to said housing body, to detect sound waves propagating through the surface mounting region of the machinery and produce said detection signals along said communications interface.

16. An acoustic sensing device according to claim 15 wherein said coupler is selected from a group consisting of a coaxial connector, a multi-pin connector and an MIL Type connector.

17. An acoustic sensing device according to claim 15 wherein the first end portion of said housing body is formed as a substantially planar wall having a substantially planar outer contact surface oriented in a facing relationship to the surface mounting region of the machinery when the housing body is removably attached relative thereto.

18. An acoustic sensing device according to claim 17 wherein said wall has a substantially planar inner contact surface, said acoustic emissions sensor including a piezoelectric transducer having a mounting face immovably secured to said inner contact surface and extending longitudinally within the housing interior from said mounting face to terminate in an unrestrained free end portion, said piezoelectric transducer operative upon exposure to the sound waves to stress longitudinally within the housing interior and produce corresponding transducer signals.

19. An acoustic sensing device according to claim 18 wherein said acoustic emissions sensor includes conditioning circuitry in electrical communication with said piezoelectric transducer for receiving said transducer signals and producing said detection signals.

20. An acoustic sensing device according to claim 19 wherein said conditioning circuitry is contained on a common circuit board disposed with said housing interior.

21. An acoustic sensing device according to claim 20 including a retainer which immovably supports said circuit board within the housing interior.

22. An acoustic sensing device according to claim 15 wherein said acoustic emissions sensor includes a piezoelectric transducer adapted upon exposure to the sound waves propagating through the surface mounting region of the machinery to mechanically stress and produce corresponding transducer signals, and conditioning circuitry for receiving said transducer signals and for producing said detection signals.

23. An acoustic sensing device according to claim 15 wherein said mount is formed integrally with said housing body and projects from the first end portion thereof.

24. An acoustic sensing device according to claim 23 wherein said housing body includes a main body section that includes said mount and an end cap secured to said main body section.

25. An acoustic sensing device according to claim 24 including a plurality of fastening elements for securing said end cap to said main body section.

26. An acoustic sensing device according to claim 24 wherein each of said main body section and said end cap is formed from an electrically conductive material.

27. An acoustic sensing device according to claim 24 wherein said main body section is formed from an electrically conductive material and said end cap is formed from an electrically conductive material having an insulative coating, and including an electrically conductive compression spring interposed between facing portions of said main body section and said end cap.

28. An acoustic sensing device according to claim 15 including a mounting adapter for removably attaching said housing body relative to the surface mounting region of the machinery.

29. An acoustic sensing device according to claim 28 wherein said mount includes a threaded projection of a selected thread size which extends from the first end portion of said housing body, and wherein said mounting adapter has a correspondingly sized first threaded bore formed therein for matably receiving said threaded projection.

30. An acoustic sensing device according to claim 29 wherein said mounting adapter has a second threaded bore for threadedly engaging a correspondingly sized threaded tapping screw projecting from the surface mounting region of the machinery.

31. An acoustic sensing device according to claim 29 wherein said mounting adapter includes an associated threaded projection of a selected thread size which is adapted to threadedly engage a correspondingly sized threaded bore formed in the surface mounting region of the machinery.

32. An acoustic sensing device according to any of claims 28 and 29 wherein said mounting adapter includes a set of magnetic elements for magnetically coupling said mounting adapter to the surface mounting region of the machinery.

33. An acoustic sensing device for use in transmitting to a measuring instrument detection signals indicative of sound wave levels detected from machinery, said acoustic sensing device comprising:

(a) a housing body including;

i. mounting means for removably attaching said housing body relative to a surface of the machinery; and

ii. coupling means for removably attaching said housing body to the measuring instrument along an appropriate communications interface, thereby to define a coupled state for said housing body; and

(b) an acoustic emissions sensor supported within said housing body proximate to said mounting means and in electrical communication with said coupling means, said acoustic emissions sensor operative when the measuring instrument is coupled to the housing body to detect sound waves propagating through the surface of the machinery and produce said detection signals along said communications interface.

34. A system for monitoring acoustic emissions from machinery, comprising:

(a) at least a first acoustic sensing device for detecting sound wave levels emanating from the machinery, said acoustic sensing device comprising;

i. a housing assembly removably attached relative to a first surface mounting region of the machinery; and

ii. an acoustic emissions sensor disposed within said housing assembly and operative upon activation to detect a presence of sound waves propagating through the first surface mounting region of the machinery and to produce corresponding detection signals;

(b) measuring instrumentation coupled to said acoustic emissions sensor via a first communications interface, said measuring instrumentation operative upon receipt of said detection signals from the acoustic emissions sensor to display perceptible output indicative of the detected sound wave levels.

35. A system according to claim 34 wherein said housing assembly is removably attached to the surface of the machinery.

36. A system according to claim 34 wherein said housing assembly includes a housing body and a coupler which interconnects said housing body to the measuring instrumentation, said acoustic emissions sensor contained within said housing body.

37. A system according to claim 36 wherein said housing assembly includes a mount removably interposed between said housing body and the surface of the machinery.

38. A system according to claim 34 wherein said measuring instrumentation is a vibration analyzer having an internal power supply for activating said acoustic emissions sensor.

39. A system according to claim 34 wherein said measuring instrumentation includes a spectrum analyzer and an auxiliary handheld unit which supports an auxiliary power supply, said acoustic sensing device being coupled to said spectrum analyzer through said auxiliary handheld unit.

40. A system according to claim 34 including a second said acoustic sensing device removably attached relative to an associated second surface mounting region of the machinery, said second acoustic sensing device having an associated second acoustic emissions sensor coupled to said measuring instrumentation via a second communications interface, and including a switch operative in a first switch condition to interconnect an input of said measuring instrumentation to an output of said first acoustic sensing device and operative in a second switch condition to interconnect the input of said measuring instrumentation to an output of said second acoustic sensing device.

41. A system according to claim 40 wherein said measuring instrumentation includes a spectrum analyzer and an auxiliary handheld unit containing an auxiliary power supply and said switch, each of said acoustic sensing devices being coupled to said spectrum analyzer through said auxiliary handheld unit.

42. A method for monitoring acoustic emissions from machinery, comprising:

(a) mounting an acoustic sensing device relative to a surface of the machinery thereby to expose said acoustic sensing device for a selected exposure period to sound waves propagating through said surface;

(b) coupling said acoustic sensing device with a measuring instrument along a communications interface;

(c) transmitting an initial set of detection signals from said acoustic sensing device to the measuring instrument along said communications interface, said initial set of detection signals corresponding to sound wave levels propagating through said surface which are detected by said acoustic sensing device during an initial reading interval; and

(d) displaying on said measuring instrument perceptible output correlated to the initial set of detection signals received from the acoustic sensing device during the initial reading interval.

43. A method according to claim 42 including decoupling said acoustic sensing device from the measuring instrument for a selected time interval and thereafter re-coupling said acoustic sensing device to the measuring instrument and transmitting a subsequent set of detection signals from the acoustic sensing device to the measuring instrument corresponding to sound wave levels propagating through said surface during a subsequent reading interval.

44. A method according to claim 43 including displaying on said measuring instrument perceptible output correlated to the subsequent set of detection signals received from the acoustic sensing device during the subsequent reading interval.

45. A method according to claim 43 including comparing the subsequent set of detection signals to the initial set of detection signals.

46. A method for monitoring emissions from machinery, comprising:

(a) mounting a plurality of sensing devices each to a respective surface mounting region of the machinery, wherein at least one of said sensing devices is an acoustic sensing device operative in response to sound waves propagating through its respective surface mounting region to produce corresponding acoustic detection signals;

(b) selectively interfacing each of said sensing devices with measuring instrumentation;

(c) selectively receiving from each of said sensing devices, during a plurality of associated reading intervals, corresponding sets of readings, whereby the sets of readings from said acoustic sensing device corresponds to sound wave levels propagating through its respective surface mounting region during its associated reading intervals; and

(d) displaying perceptible output on said measuring instrumentation corresponding to the associated sets of readings received by the measuring instrumentation from each of said sensing devices.