电动执行机构蜗杆传动支承设计及转速对强度的影响

Influence of the Rotate Speed and Fulcrum Bearing Design on the Strength of Electric Actuator Worm Transmission

对蜗轮蜗杆传动横向受力模型进行了简化。通过基本的材料力学知识,推导出了蜗轮蜗杆传动中蜗杆所受横向力的计算公式。在一定载荷下,蜗杆横向弯曲刚度、转速和支承间隙是蜗杆横向冲击弯曲应力的主要影响因素。通过对两种不同电动执行机构产品的分析,给出了电动执行机构蜗杆传动支承设计的建议。高速时,应着重考虑冲击作用对蜗杆强度的影响;低速时,应着重考虑静力对蜗杆传动强度的影响。在高低速设计时,间隙考虑也不同,高速时应当稳固,尽量避免间隙支承,低速时为了装配方便,可以采用适当的间隙配合。

The transverse force model of worm gear drive is simplified.The formula of transverse force model of worm gear drive is deduced by using material mechanics.The lateral bending rigidity of worm,rotational speed and bearing clearance are main influence factors of transverse impact bending stress of the worm gear under certain loads.The design suggestions of the electric actuator worm gear fulcrum bearing are given by analyzing two kinds of different products.The impact is considered as the key influence factor at high-speed,and so as the static force at low-speed.The fulcrum bearing gaps are designed differently when the worm gear rotates at high-speed and low-speed respectively.The fulcrum bearing should be stable and the clearance should be avoided by best efforts at high-speed,and a proper clearance is allowed for requirements of assembling at low-speed.