机械5

重型自卸车货箱与举升装置设计 摘要 自卸汽车是利用发动机动力驱动液压举升机构，将货箱倾斜一定角度从而达到自动卸货的目的，并依靠货箱自重使其复位的。自卸机构负责货物的举升倾卸，卸货时驾驶员操纵液压阀的控制手柄，动力由发动机输出经变速器再到取力器，取力器驱动液压泵给液压缸提供动力，液压缸推动货箱实现货物的倾卸。液压举升机构是自卸汽车的重要工作系统之一，其结构形式、性能好坏直接影响自卸汽车的使用性能和安全性能。 本次设计的主要内容集中于自卸汽车液压缸及液压系统的设计，介绍了液压设计的前期准备工作：设计的依据、设计的一般原则和设计步骤。通过对自卸汽车举升机构几种方案的比较,确定该车的举升机构的方案,并对该方案进行了力学分析计算和液压系统设计。设计采用直推式举升机构,具有结构简单,行程长,兼具经济性的特点。然后对液压缸的刚度、强度、系 统压力、升降时间进行了验算和校核，最终确定了该方案的合理性和安全性。另外，本说明书对取力器和货箱也进行了设计和计算。 关键词：自卸汽车，液压系统，举升机构，取力器 HEAVY DUMP TRUCK PACKING CASE AND THE DESIGN OF LIFTING DEVICE ABSTRACT The dump truck uses the e
ngi
ne power actuatio
n hydraulic pressure lifti
ng orga
nizatio
n, packi
ng co
ntai
ner i
ncli
ne certai
n a
ngle, thus serves the purpose which u
nloads cargo automatically, a
nd depe
nds upo
n the packi
ng co
ntai
ner dead weight to cause its replaceme
nt. The auto-dumpi
ng mecha
nism is mai
nly respo
nsible for the lifti
ng a
nd dumpi
ng of the goods.Whe
n the goods are
needed to be u
nloaded, the operator will co
ntrol the ha
ndle of the hydraulic valve,a
nd the
n the goods are dumped by the series of e
ngi
nes from the e
ngi
ne to the gearbox,a
nd the
n to the power-out device drivi
ng the liquid pump to give the power to liquid ta
nk ,which pushes the compartme
nt to tilt the goods. The hydraulic pressure lifti
ng orga
nizatio
n is o
ne of dump truck's importa
nt work systems, its structural style, performa
nce quality immediate i
nflue
nce dump truck's operatio
nal performa
nce a
nd safety performa
nce. The co
nte
nt of this graduatio
n desig
n has focused o
n the desig
n of the dump truck hydraulic cyli
nder a
nd hydraulic systems,i
ntroduci
ng the desig
n of hydraulic desig
n preparatio
n work,a
nd the desig
n basis ,ge
neral pri
nciples a
nd steps. Compared with the several pla
ns of lifti
ng mecha
nism ,we have chose
n o
ne pla
n fi
nally,for we have desig
ned the calculatio
n of the mecha
nical a
nalysis a
nd the hydraulic system.The desig
n put to use to keep the push type lifti
ng mecha
nism,which has simple structure ,lo
ng route of travel,a
nd eco
nomic. What’s more,we alse have checked its stiff
ness,stre
ngth,systematic pressure,lifti
ng up a
nd dow
n time,fi
nally we decided the reaso
nable
ness a
nd security.I
n additio
n, we alse made the desig
n a
nd calculatio
n of the Power-Take-Off a
nd the goods’ compartme
nt. Keywords: dump truck,hydraulic pressure ur
n desig
n,hydraulic pressure system,Lifti
ng mecha
nism,Power-Take-Off 目录 第一章前言1 第二章总体方案分析及确定3 §2.1自卸汽车的分类3 §2.2总设计内容分析4 §2.3车厢设计5 §2.3.1车厢结构设计5 §2.3.2车厢选择材料6 §2.4举升机构分析6 §2.4.1液压系统的组成部分及作用6 §2.4.2自卸汽车举升机构现存方案及其优缺点7 第三章液压举升系统的设计10 §3.1举升机构设计中应考虑的问题10 §3.1.1爬行现象10 §3.1.2车厢在最大举升位置时，车厢后地板离地面的高度。 11 §3.1.3液压缸设计时应注意如下问题。 11 §3.2举升参数的确定12 §3.3液压缸举升参数的计算12 §3.3.1基本参数和计算方法的选择12 §3.3.2举升油缸直径的计算13 §3.3.3液压性能参数计算18 §3.3.4货箱举升时间的校核19 §3.4液压缸基本参数的校核19 第四章液压系统主要元件的设计计算和选择22 §4.1系统工作压力22 §4.2液压油缸22 §4.2.1举升油缸的技术参数22 §4.2.2满行程油缸充油量V 23 §4.2.3举升时间23 §4.3动力元件-----液压泵的选型与计算23 §4.4阀类元件的确定24 §4.4.1选择范类元件应注意的问题24 §4.4.2阀类元件的选择24 §4.5管路的选择26 第五章取力器的设计计算27 §5.1取力装置概述27 §5.2取力装置的设计计算27 §5.2.1已知条件27 §5.2.2齿轮的参数选择和强度计算28 总结31 致谢32 参考文献33