Analysis Of Transmission Error And Vibration With Modified Spiral Bevel Gear

With the advantages of steady transmission, low noise and high carrying capacity, spiral bevel gear now has been widely used in the field of aviation, navigation, automobile, and all kinds of precision machine tools. The precision, strength and noise of spiral bevel gear are always the biggest problems which trouble the gear industry. Nowadays, domestic researches are focused on changing the shape of tooth surface, increasing contact ratio to improve the dynamics mesh performance of spiral bevel gear. Though much work has been done by experts and scholars, has made great progress, the problem remains. Based on the non-zero modification theory, a pair of spiral bevel gears with high load capacity is designed in this thesis, then modification of tool is designed and processed, and tooth face can be modified with the new tool. The goal to improve strength and reduce noise is reached finally. For convenience, the spiral bevel which cutted by the method befor-mentioned,will be called"modified spiral bevel gear",and the spiral gear which cutted by the common cutter will be called"ordinary spiral gear".Based on differential geometry and the meshing theory of gears, the tooth surface equation is established. Through the TCA analysis, two kinds of spiral bevel gears of the transmission error curves are respectively simulated, and the results are compared and analyzed.According to the characteristics of transmission error,experimental apparatuses are reasonably selected, spiral bevel gear transmission error measurement system is designed. Then we tested two pairs of spiral bevel gears respectively with different load and recorded the experimental data.The collected data are studied with time-domain analysis and frequency domain analysis, and the results are compared. The corresponding low-pass and band-pass digital filter are designed based on the frequency domain analysis results. The experimental signals are filtered and the filtered signals are compared and analyzed.According to vibration testing theory, the appropriate experimental apparatuses are chosen, vibration test system is designed. Two pairs of spiral bevel gears are respectively tested under different rpm and loads and the experimental results were compared and analyzed.The results showed: Modified spiral bevel gear is better than ordinary spiral bevel gear in the dynamic behavior. It can be proved that tooth face can be modified with the new tool; this new method is useful and effective to improve the strength of spiral bevel gear, reduce its noise and improve the performance of the dynamic mesh.