The Study Of The Diagnosis Method For Aerospace Bearings' Faults And The Development Of The Software System

Aerospace bearing is one kind of the highest requirement for friction torque. Among them, the quantity and stability of startup friction torque and dynamic friction torque of gyroscope framework sensitive bearing play an important role in instructions accuracy and stability of the gyro instrument, then also play an important role in the control system performance and spacecraft security. To miniature space sensitive bearings, processing defects and surface scratches of internal and external circle roundness, roughness, grinding in gully silk flow, radial clearance and gully shape will affect the start-up and operation torque of bearings, make friction torque of bearings appear "peak points", "dead spots" and volatility, even cause the ball stopped. So by study and analysis, it is very necessary to use many kinds of effective methods to diagnose faults of aerospace bearings caused by these factors, and it is of great realistic significance for improving the quality, ensure the life and the reliability of aerospace bearings and reduce the economic loss.Since the friction torque plays an extremely important role in the working condition of the gyroscope framework sensitive bearings, in this paper dynamic friction torque waveforms of two types of these bearings were collected from LSD-I type dynamic friction torque tester. Friction torque waveforms of several single defects, such as inner and outer ring bad gully shape, inner ring bad roundness, inner ring bad roughness, inner and outer ring grinding silk flow, were analyzed and studied, by the use of mathematical tools of Fourier transform, wavelet analysis and statistics etc. to carry on time domain and frequency domain analysis, probability density function analysis, power spectrum analysis, envelope spectrum analysis and other parameters calculation, and to try to find characteristics of waves affected by various defects, then to conclude preliminary criterion of the traction torque for diagnosing process defects of aerospace bearings, and to form effective diagnosis methods. Finally the fault diagnosis software system was preliminary developed by LabVIEW, and was carried out.The research subject is a very difficult work for it is a lot of active factors, wide in relative aspects, strong on randomicity, conplex in interaction and sansitive to work conditions. This paper has made a further study and analysis on the basis of previous studies, preliminarily finding effective methods for diagnosing these sensitive bearings with single defects, and methods has been verified in software development system. It would lay the foundation of continuous study for diagnosis faults of aerospace bearings according to friction torque wavefoms.