CVT锥轮推力平衡模型及影响因素研究

为提高无级变速器速比控制的精度与稳定性，研究了主从锥轮推力的关系及其影响因素.采用理论分析与试验验证相结合的方法，建立了主从锥轮推力比的数学模型，通过台架试验验证了模型的正确性，并且，通过台架试验研究了速比、转矩比、输入转矩与主动轮转速平衡推力比的影响.结果表明，平衡推力比与主从锥轮工作包角的比值成比例关系；推力比与速比呈单调递减的关系；同一速比下，输入转矩越大，推力比越大；推力比随转矩比的增大而线性增大，针对同一转矩比，最大转矩值越大，推力比就越小；主动轮转速对推力比的影响可以忽略.本文研究了推力比的平衡机理，为速比的精确控制提供了理论与试验依据.
In order to improve the speed ratio control accuracy and stability of Continuously Variable Transmissions (CVTs), the thrust balance impact factors were studied and the relationship between the primary pulley thrust and the secondary pulley thrust was analyzed. Theoretical analysis and experiment verification methods were utilized. A math model for thrust ratio was developed. The impact on balance thrust ratio from speed ratio, torque ratio, input torque and primary speed was investigated in test bench experiment. The results are as follows: 1) the balance thrust is proportional to the ratio between the primary and secondary working wrap angles; 2) The thrust ratio becomes smaller when the input torque is larger under the same speed ratio condition; 3) The thrust ratio increases when the input torque ratio becomes larger; 4) The thrust becomes smaller when the maximum input torque becomes larger under the same torque ratio condition; 5) The impact from primary speed can be ignored. This paper explains the balance mechanism of thrust ratio and provides a theoretical and experimental basis for controlling speed ratio accurately.