Device and process for machine diagnostics by means of vibration measurement

• US 8,355,881 B2
• Filed: 08/12/2009
• Issued: 01/15/2013
• Est. Priority Date: 08/12/2008
• Status: Expired due to Fees

• Current Assignee: Prueftechnik Dieter Busch Ag (Fortive Corp.)
• Original Assignee: PRÜFTECHNIK Dieter Busch AG (Fortive Corp.)
• Inventors: Kuchler, Alexander
• Primary Examiner(s): Barbee, Manuel L
• Application Number:
  US12/539,706
• Publication Number:
  US 20100042343A1
• Time in Patent Office: 1,252 Days
• Field of Search: 702/39, 702/56, 702/76, 702/77, 702/189, 702/190, 702/182, 702/183
• US Class Current: 702/56
• CPC Class Codes: G01H 1/12 of longitudinal or not specified vibrations
• 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 29/46 by spectral analysis, e.g. Fourier analysis or wavelet analysis spectral signal processing per se G06F17/14

Abstract

A device for machine diagnostics, with a vibration sensor (12) for detecting vibration signals on the machine (10), a unit (14) for conditioning the vibration signals, an A/D converter (16) for digitizing the conditioned vibration signals, a data processing unit (20) for splitting the digital signals into at least two frequency ranges, the data processing unit being made to scale the signal for each frequency range to an amplitude resolution which is less than the amplitude resolution of the A/D converter, and an evaluation unit (30) for further evaluation of the split signals.

Claims

1. Device for machine diagnostics, comprising

a vibration sensor for detecting vibration on a machine and outputting vibration signals representative of vibration detected,

a conditioning unit for conditioning the vibration signals,

an A/D converter for digitizing the conditioned vibration signals,

a data processing unit directly connected to the A/D converter for splitting the digitized signals received directly from the A/D converter into parallel split signals for at least two different frequency ranges, the data processing unit being adapted for scaling the signal for each of the different frequency ranges to an amplitude resolution which is less than the amplitude resolution of the digitized signals produced by the A/D converter, and

an evaluation unit receiving the parallel split signals for evaluation and modification.

2. Device in accordance with claim 1, wherein the A/D converter has a sampling rate of at least 100 kHz.

3. Device in accordance with claim 1, wherein the A/D converter has an amplitude resolution of at least 18 bits.

4. Device in accordance with claim 3, wherein the amplitude resolution for each of the frequency ranges is a maximum 16 bits.

5. Device in accordance with claim 1, wherein the A/D converter comprises sigma-delta technology.

6. Device in accordance with claim 1, wherein the data processing unit and the evaluation unit are separate modules, each of which is connected to a memory by direct memory access via which the signals are transferred.

7. Device in accordance with claim 1, comprising a plurality of input channels, each input channel being provided with a respective conditioning unit, A/D converter and data processing unit for frequency splitting.

8. Device in accordance with claim 1, wherein each of the frequency ranges has an amplitude resolution that is at least 2 bits less than the resolution of the digitized signals produced by the A/D converter.

9. Device in accordance with claim 1, wherein the data processing unit is adapted for splitting the signals prior to performing any data processing of the digitized signals.

10. Device in accordance with claim 1, wherein the data processing unit is adapted to at least one of further filter and otherwise modified the split digital signals.

11. Process for machine diagnostics, comprising the steps of:

detecting vibration on a machine by means of a vibration sensor which produces vibration signals representative of vibration detected,

conditioning the vibration signals,

digitizing the conditioned vibration signals by means of an A/D converter,

splitting the digitized signals into parallel split signals for at least two different frequency ranges by means of a data processing unit that is directly connected to the A/D converter, and for each frequency range, the signal being scaled to an amplitude resolution which is less than the amplitude resolution of the digitized signals produced by the A/D converter, and

transferring the parallel split signals to an evaluation unit for evaluation and modification.

12. Process according to claim 11, wherein the data processing unit and the evaluation unit are separate modules, each of which is connected to a memory, wherein signals are transferred between the memory and each of the data processing unit and the evaluation unit by direct memory access.

13. Process according to claim 11, wherein the data processing performed on the split signals comprises Fourier Transform processing.