Wavelet Transformation's Application In Gear Box Fault Diagnosis

As a result of enlargement,automation,complication and succession of mechanical equipment and the keen market competition in recent years,people raise a higher claim for accuracy and speediness of mechanical failure diagnosis.The gear drive is one of the most general modes in mechanical equipment,the importance of the condition testing and fault diagnosis of its transmission system consists not only in cutting time and cost of repairing,but also in raising diagnosing accurate,which improves repairing speed.In this thesis,some research and application work with wavelet and in the field of fault diagnosis of gearbox has been conducted.And wavelet analysis,a new time and frequency analysis method,is used in the field of mechanical fault diagnosis.The type of the gearbox is JZQ250 and made as test object.Firstly,based on the fault mechanism and vibration trait of the gearbox in the practical state of work,the experiment project on condition testing and fault diagnosis of the gearbox is designed,the vibration signals of the gearbox are tested and denoised by applying the wavelet packet analysis.Secondly,The vibration trait information of the gear's wearing is identified on the basis of wavelet coefficient.While this text diagnoses bearing's failure such as spot with power spectrum.Finally,it is an effective and reliable method to analyze signals and diagnose gearbox on the basis of wavelet alternation.The analysis result indicates that the wavelet transform simultaneously has the good attribute signal partial characteristic and feature extraction ability in the time domain and the frequency range.The use of wavelet transform method can diagnose on the gearbox running status effectively and be used the diagnosis of machinery and equipment.