The Study About Feasibily Forecasting Of The Automobile Gear's Failure

When the mechanical device is running, motion and force are ransmittedthrough engagement between the driving gear and driven gear in geared system,and the mechanical vibration must be generated. The state of mechanical vibration can be changed by wear, pit, the error of manufacture and installationas well as various defaults of gear. Therefore, vibration signal of geartransmission is information carrier that displays the condition of gear. It contains ample information on normal and abnormal of gear transmission. Various faults of gear and geared system can be diagnosed naturally bymonitoring and analyzing vibrational signal.This article, first, mathematical models of one kind of gear fault in one— stage gearbox (the fatigue crack on root of tooth) are established on the basis of gear dynamics. Then, the boundary value problems of ordinary differential equations that are governed by the mathematical models are solved by the numerical method. Last, one kind of gear fault is numerically simulated so that influence of gear fault tochange of vibrational state is studied in theory, and the symptom generated by faults is found.The path of vibration spread is from gear to shaft, then to bearing and finally to the surface of box. Therefore, vibration signal of gear transmission is information carrier that displays the condition of gear. It has a function of magnifying or attenuating the frequency content of signal. The influence of path of vibration spread on vibrational signal measured is studied by theory analysis and measuring transfer function in chapter three. The vibration signalon the measured point of gearbox surface is formulated with impulse responsible function, which establishes theoretical basis of independent component decompose being applied to gear fault diagnosis.Because of the nonlinearity of contact distortion between teeth, mesh...