System of analysis by visual display of the vibratory movements of a rotary machine

• US 4,423,635 A
• Filed: 05/19/1982
• Issued: 01/03/1984
• Est. Priority Date: 05/21/1981
• Status: Expired due to Fees

• Current Assignee: Societe Nationale ELF Aquitaine Tour Aquitane
• Original Assignee: Societe Nationale Elf Aquitaine (Cook Composites and Polymers)
• Inventors: Tebec, Jean-Louis, Senicourt, Jacques-Marie
• Primary Examiner(s): Birmiel, Howard A.
• Application Number:
  US06/379,984
• Time in Patent Office: 594 Days
• Field of Search: 73/660, 73/593, 340/682, 340/683
• US Class Current: 73/593
• CPC Class Codes: G01H 1/003 of rotating machines G01H1/10 takes precedence
• CPC Class Codes: G01M 1/22 and converting vibrations due to imbalance into electric variables

Abstract

The invention relates to a system of analysis by visual display of the vibratory movements of a rotary machine having at least one shaft supported by at least one bearing.

This system comprises two first transducers transmitting electrical signals as a function of the relative displacements of the shaft with respect to the bearing, positioned in the bearing and forming between the two transducers an angle of 90°, two second transducers transmitting electrical signals as a function of the absolute displacements of the bearing and positioned level with the bearing forming between the two transducers an angle of 90°, control and detection means connected to the first and second transducers, means for combining the electrical signals from the detection means making it possible to determine the absolute movement of the shaft, display means for producing and positioning two groups of animated or moving circles so as to display the real image of the machine.

Claims

1. A system of analysis by visual display of the vibratory movements of a rotary machine comprising at least one shaft supported by at least one bearing, wherein said system comprises for each bearing and that part of the shaft supported by the bearing, two first transducers able in each case to transmit electrical signals as a function of the relative displacements of the shaft relative to the bearing, said two first transducers being located in the bearing facing the shaft in such a way that they form a given angle between the transducers;

two second transducers each able to transmit electrical signals which are a function of the absolute displacements of the bearing, said two second transducers being positioned level with the bearing so that they form a given angle between the transducers;

control means for controlling the first and second transducers;

detection means for detecting electrical signals from the two first and two second transducers;

means for combining the electrical signals from the detection means for determining the absolute movements of the shaft; and

wherein said system comprises display means;

means for simultaneously producing on the said display means two groups of animated or moving circles, the movements of the circles of the first group representing the displacements of the shafts in the bearings and the movements of the circles of the second group representing the displacements of the bearings; and

means for positioning the two groups of moving circles on the display means so as to represent the image of the machine.

2. An analysis system according to claim 1, wherein one of the first transducers is aligned with one of the second transducers and the other first transducer is aligned with the other second transducer.

3. An analysis system according to claim 1, wherein the two first transducers are displacement transducers.

4. An analysis system according to claim 3, wherein the displacement transducers are eddy current transducers.

5. An analysis system according to claim 1, wherein the two second transducers are accelerometers and it also comprises means for the double integration of the electrical signals from said second transducers, said integration means then being placed in front of the combination means for the signals.

6. An analysis system according to claim 1, wherein the two second transducers are velocity microphones and it also comprises means for the single integration of the electrical signals from said second transducers, these integration means then being placed in front of the signal combination means.

7. An analysis system according to claims 5 or 6, wherein it also comprises means for amplifying the electrical signals from the single integration means or double integration means.

8. An analysis system according to claim 1, wherein the two second transducers are displacement transducers.

9. An analysis system according to claim 8, wherein the two second displacement transducers are eddy current transducers.

10. An analysis system according to claim 1, wherein the system also comprises means for eliminating the polarization of the electrical signals from the first and/or second transducers.

11. An analysis system according to claim 1, wherein the system also comprises means for the amplification of the electrical signals from the first and second transducers.

12. An analysis system according to claim 1, wherein the system also comprises means for eliminating the unwanted electrical signals or run-out from the first transducers and which are not a function of the displacements of the shaft.

13. An analysis system according to claim 1, wherein the system also comprises means for calibrating the amplitude of the electrical signals from the two first and two second transducers.

14. An analysis system according to claim 1, wherein the angle formed between the two first transducers and between the two second transducers is 90°

.

15. An analysis system according to claim 1, wherein the display means comprise a display unit with two units X and Y, provided with a screen and a Wehnelt control, as well as a multiplexing system with four inputs per bearing and two outputs corresponding to inputs X and Y of the display unit.

16. An analysis system according to claim 14, wherein the means for slowing down the animation of the circles are constituted by a regulatable frequency stroboscope connected to the Wehnelt control of the display unit.

17. An analysis system according to claim 16, wherein it also comprises means for displaying the circle animation frequency connected to the stroboscope.

18. An analysis system according to claim 1, wherein the display means also comprise means for slowing down the animation of the circles.

19. An analysis system according to claim 1, wherein the means for producing the animated circles are constituted by a generator generating two groups of sinusoidal electrical signals phase-displaced by an angle of π

/2 and means for synthesizing the electrical signals as a function of the displacements of the shafts and the bearings and the sinusoidal electrical signals.

20. An analysis system according to claim 1, wherein the system also comprises means for selecting either absolute movements of the shafts and bearings, or relative movements of the shafts with respect to the bearings.

21. An analysis system according to claim 1, wherein the system also comprises means for measuring the displacement values of the shaft and bearings and the phase displacements of the different movements observed.

22. An analysis system according to claim 1, including means for analyzing the vibratory movements of several rotary machines each having at least one shaft supported by at least one bearing, wherein the system comprises means permitting the storage of the respective positions of the animated circles corresponding to each of the said machines.