Dynamic analysis method of rotating shaft with magnetic pattern

Heng-Sheng Hsiao,Jen-Yuan (James) Chang,Shuo-Wu Shih

doi:10.1063/1.4973844

Abstract

Vibration issue in rotating system has existed mostly due to imbalance response of a rotating shaft. In general, accelerometers or eddy current probes are commonly used to measure the shaft’s dynamic changes in form of acceleration and displacement. Originated from coding and operating algorithm of hard disk drive, a method to detect the position error of read head is applied on measuring and analyzing dynamic response of rotating shaft system. By magnetizing the pattern on magnetic medium surrounded on the rotating shaft, analog signal can be acquired to determine the shaft’s axial and radial displacement. In this paper, a method of dynamic measuring on rotating shaft is proposed by using magnetic pattern and validated through calibrated experiments.

Highlights

Rotating shaft is a commonly used mechanism in industrial applications, and its vibration problem has always been an issue during operation
Vibration monitoring is useful for the analysis of tool life, tool integrity, part quality, and prevention of unexpected tool failure that can result in unscheduled downtime
When the shaft is rotating in a conical trajectory, the output signal from sensor would be processed by high speed processor for comparing with data in look-up table to calculate the corresponding dynamic response in each sector

Summary

INTRODUCTION

Rotating shaft is a commonly used mechanism in industrial applications, and its vibration problem has always been an issue during operation. Vibration in rotating shaft has various causes including critical speed, imbalance response, and flow-induced vibrations.[1] Imbalance faults are common issues in mechanical assembly, of which faults occur when the mass of mechanical components is not evenly distributed with respect to rotating center or coupling misalignments. These imbalances would cause unwanted dynamic loads and vibrations of the rotor during machine operation. To overcome such constraints a method is proposed to measure the dynamics of a rotating shaft using specific magnetic pattern on magnetic medium and a signal processor to process signals from analog Hall-effect sensor

OPERATING PRINCIPLE

ALGORITHM FOR ROTATING DYNAMICS AND SPEED

EXPERIMENTAL RESULTS

CONCLUSION