Design And Analysis Of Composite Motion Curve-face Gears

Curve-face gear is a new type of orthogonal variable transmission ratio gear pair based on non-circular bevel gear. It combines the transmission characteristics of non-circular gear, on-circular bevel gear and face gear, and can be used to transmit motion and power. It has great potential applications in the fields of engineering machinery, agricultural machinery, textile machinery, automobile and others. Composite curve-face gear pair is a new type of rotation/translation motion gear pair base on the curve-face gear. It has the characteristics of simple structure, small volume and weight; it can replace some traditional composite motion mechanism. Therefore, the research on the composite motion curve-face gear has great significance.This issue derives from Natural Science Foundation of China(Design theory and manufacturing technology research on the variable transmission ratio face gear engagement transmission: 51275537), and the main purpose is to analysis the basic movement principles, composite motion law, force condition, dynamics characteristics and experiment methods of composite motion curve-face gear. In the thesis, the research work has been organized aiming at composite motion curve-face gear drive as following:According to the basic principles of mechanism theory, the basic movement law of the composite motion curve-face gear was analyzed. The scope of the teeth number of the spur gear was discussed. And the proper meshing conditions of the gears and the prevent floating condition were also discussed.Using the theory of differential geometry and higher mechanism theory, the kinematic analysis method of composite motion curve-face gear was built. The transmission ratio and the axial movement law of the composite motion curve-face gear were obtained. The variation law of axial movement of the gear pair with gear eccentricity, modulus, number of teeth and the order of the curve-face gear was revealed.Based on MATLAB and VB, the calculation software of the composite motion curve-face gear was developed. Based on the theory of the mechanical design basis, the force condition of the composite motion curve-face gear was analyzed. The variation law of pressure angle and meshing force with rotation speed and teeth number of the gear pair were obtained. The transmit characteristics of the composite motion curve-face gear was revealed.Using the theory of gears system dynamics, for curve-face gear, using the method of lumped parameters, in consideration of the gear backlash, time-varying mesh stiffness and external torque changes, the establishment of dynamics model of curve-face gear pair was established. The dynamic response of the gears meshing at different meshing frequencies were obtained.Using the Modern design and test methods, the simulation model, the variation test platform and the transmission test platform of composite motion curve-face gear were designed and built. Through the laser displacement sensor and the torque sensors, the rotation speed, torque of the input and output shaft and the displacement of the output shaft were measured. By comparison with theoretical values, the theoretical calculation method was verified to be reasonable and correct. The vibration characteristics and transmission efficiency of the gear pair were tested. The engineering practice of the gear pair was discussed in this paper and its application characteristics was analyzed. It laid the theoretical foundation for the practical application of the composite motion curve-face gear.