重型自卸车主副一体式专用车架设计

太原理工大学硕士研究生学位论文

重型自卸车主副一体式车架的设计

摘要

目前，国内公路型重型载货自卸汽车整车的生产，主要由改装车厂在整车厂提供的基本型载货汽车平台上派生的自卸汽车底盘上，根据用户需求进行自卸作业系统的设计和改装生产，实现最终的自卸汽车整车。随着我国重型载货汽车快速发展，专业用户对自卸汽车综合性能及可靠性要求的不断提升，使得改装设计生产模式已经不能适应自卸汽车细分市场的发展需求。将重型自卸汽车以底盘与上装一体化设计是解决该问题的主要途径。取消副车架自卸车的设计不仅能实现轻量化，而且可降低整车的重心，提高行驶稳定性，因此，进行取消副车架的重型自卸车主副一体式车架的设计研究具有十分重要的实际意义。

本文从重型自卸汽车车架与上装作业部分一体化设计为主线，通过对装有副车架的TY-1型自卸车车架为分析对象，提出设计硬点参数，在此基础上，取消副车架，提出直接与上装作业部分实现对接的专用自卸车车架总成结构设计方案，并进行分析，为专用自卸汽车整车一体化设计，提供核心部件的设计参考依据。

首先以装有副车架的TY-1型自卸车车架为研究对象，运用有限元方法对其进行静载工况、卸载初工况和货箱举升至45°工况的结构强度分析，并分析其自由模态，获得该车架的应力分布情况和动态特性，并对该车架进行了模态试验，得到车架前8阶自由模态频率和振型，验证有限元模型的可信性。在此基础上，取消了副车架，并重新设计主副一体式车架。该车

I

太原理工大学硕士研究生学位论文

架纵梁的结构形式为工字型，基于等强度考虑，纵梁前部采用变截面结构，论文设计了四种纵梁截面尺寸的车架结构，且车架的静弯曲应力都能满足强度要求。

其次，对所设计的新车架进行相同工况下稳态力学分析，并比较各车架结构参数，通过综合分析对比，确定TY-G3型车架为所设计车架形式，该车架的强度优于TY-1型车架，重心降低14.35%，重量降低11.18%，满足设计要求。TY-G3型车架的有限元模态分析结果显示，车架的一阶频率有所提高，动态性能得以改善。

最后，结合尺寸优化和拓扑优化的方法对TY-G3车架结构进行优化设计，车架的重量减少了0.29t，降低幅度为19.2%，在实现车架轻量化的同时，车架的材料布置更加合理，强度也得以提高。

关键词：低重心，重型自卸车，副车架，变截面，优化设计

II

太原理工大学硕士研究生学位论文

HEA VY-DUTY DUMP TRUCK INTEGRAL FRAME DESIGN

ABSTRACT

At present, the domestic road type heavy duty truck dump truck production, the basic type of truck platform provided by the modified car factory in the vehicle on the dump truck chassis derived according to user needs to design the dump operation system and modified production, realize self unloading automobile final.With the rapid development of China's heavy truck, dump truck professional users requirements for comprehensive performance and reliability of continuous improvement, make the modification design mode of production has been unable to meet the development needs of market segments of the dump truck. Heavy dump truck chassis and is provided with integrated design is the main way to solve the problem. Cancel the auxiliary frame design of dump truck can not only realize the lightweight, but also can lower the center of gravity, improve driving stability. Therefore, has a very important significance for heavy duty dump truck integral frame design to cancel the auxiliary frame.

This paper with the frame of heavy dump truck is part of integrated design and operation as the main line, through to the TY-1 type with a subframe dump truck frame as the analysis object, puts forward the design point parameters, on

III

太原理工大学硕士研究生学位论文

the basis of this, to cancel the auxiliary frame, the direct part and is provided to the work to achieve special dump truck frame assembly structure design, and carries on the analysis, for the special dump truck vehicle integration design, provides the core components of the design reference.

Based on the TY-1 type with a sub-frame of the dump truck frame as the research object, using the finite element method, analysis its structural strength in the condition of static state, the beginning of the unloading and cargo lift to 45 ° condition, and analysis of the free modal, stress distribution and dynamic characteristics of the frame was obtained. The experimental modal analyses have been done, obtaining first 8 order free modal frequency and vibration, validating the credibility of finite element model. On this basis, cancel the auxiliary frame, and redesign the integral frame. The structure of the frame longitudinal beam is I-shaped. Based on strength considerations, the front of the longitudinal beam convert into variable cross-section structure. This paper designed four kinds of longitudinal beam cross-section size, and the frame static bending stress can meet the strength requirements.

Secondly, under the same conditions, analyzing the steady-state of the redesigned frame, and comparing the structure parameters of each frame. By comprehensive analysis and comparison, it was confirmed that its form is the TY-G3 frame. The new frame strength is better than TY-1 type, the mass is reduced by 1.6% and the centre of gravity is decreased by 11.18%. The finite element modal analysis results show that the first-order frequency of new frame

IV