门座起重机变幅机构两级制动的设计计算

Design and Calculation of Two staged Braking for the Luffing Mechanism of a Portal Crane

分析了变幅机构动能在变幅制动过程中的变化规律，导出机构运动速度随制动时间变化的关系，以及两级制动总制动时间与各级制动力矩的关系式，进而确定变幅机构两级制动的设计计算准则．

In this paper,the regulation that the luffing mechanism′s kinetic energy varies in the process of luffing braking has been analyzed.The relationship that the speed of the mechanism varies with braking time has been inferred.It also deduces a equation about the total braking time and the moments,and determines the design criterion for two staged braking of luffing mechanism.