自卸车举升机构的显式统一模型研究

A General Explicit Linear Model for Lift Mechanism of Dump Trucks

举升机构的分析计算是自卸车设计的关键内容,传统的分析方法主要有以铰接点坐标为变量的二元二次方程组方法和以杆件角度为变量的三角代数方程方法,这两种方法往往存在判根取舍的麻烦,而且不同类型举升机构的方程和判根准则也存在很大差异。基于线性变换与向量代数理论,提出一种无需判根的举升机构分析新方法,用统一的显式线性模型描述四种典型举升机构,只需要进行简单的线性代数运算即可得到任意状态下各铰接点的位置,仅需要求解二阶方程组即可得到各杆件受力,特别适合于编程实现。通过不同举升机构的分析实例,验证了所提出的模型和分析方法的有效性。

Kinetic analysis of lifting mechanism is one of core tasks for dump truck design. There are two traditional kinds of model for linkage lifting mechanism： quadratic equations with joints＇ coordinates as variables and trigonometric equations with link angles as variables. It is usually troublesome to distinguish the appropriate root in the whole lifting process. And different type of linkage lifting mechanism has different kinematic equations,which need different rule to distinguish the correct root. Based on linear transformation and vector algebra theory,a new general explicit linear model is put forward for the classic four types of linkage lifting mechanism. It is convenient to program with the new analysis model because only simple explicit linear computations are needed to calculate the coordinates of each joint and only a system of linear equations is needed to solve the loads of each link component. In the end,the proposed general model is validated with numerical examples of the classic four types of linkage lifting mechanism.