DEVICE AND PROCESS FOR MACHINE DIAGNOSTICS BY MEANS OF VIBRATION MEASUREMENT

• US 20100042343A1
• Filed: 08/12/2009
• Published: 02/18/2010
• Est. Priority Date: 08/12/2008
• Status: Active Grant

• Current Assignee: PRÜFTECHNIK Dieter Busch AG (Fortive Corp.)
• Original Assignee: PRÜFTECHNIK Dieter Busch AG (Fortive Corp.)
• Inventors: Kuchler, Alexander
• Granted Patent: US 8,355,881 B2
• Time in Patent Office: Days
• 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 for splitting the digitized signals into split signals for at least two frequency ranges, the data processing unit being adapted for scaling the signal for each frequency range 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 for further evaluation of the split signals.

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 several 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.

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

9. 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 at least two frequency ranges by means of a data processing unit, 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 split signals to an evaluation unit for further evaluation.

10. Process according to claim 9, 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.