起重机的控制.docx

江西理工大学江铜函授站毕业设计（论文）说明书设计（论文）课题：起重机的控制年级：07届专业：机电一体化设计者：黄萍指导教师：教师职称：实习单位：江铜集团年月日江西理工大学继续教育学院毕业设计（论文）任务书论文题目起重机的控制专业班级07届姓名黄萍指导教师毕业设计（论文）的内容毕业设计（论文）要求毕业设计（论文）的主要阶段计划（分前期、中期、后期）任务下发日期完成日期教研室主任： 主管教学院长：学院（盖章）IntroductionA significant word for the decade as far as the crane industry was concerned, was railways, as cranes for this industry were still very important. On 7 September 1949, for example, the Deutsche Bundesbahn (Federal German Railway) was founded. It needed high-capacity liftingdevices that could be taken to the job site as part of a train. Four steam-driven cranes, each of which could lift 57 tonnes, were ordered from Ardelt. In 1950 followed a special type of crane with a boom designed for working below overhead wires. The cranes featured a counterweight attachment system which was connected to the lifting gean This innovative design did not prove successful, but was replaced in 1955/56 by a similar hydraulic mechanism. Also in Germany, MAN had been actively building not just harbour, dockyard and travelling cranes, but also diesel-powered slewing cranes with pneumatic steering. These had been built since 1946 , were driven by a 70 kilowatt six cylindertruck engine and could lift 6 tonnes at 7 metres radius and weighed 48 tonnes. A small concession to safety was also introduced as the company brochure tells us: A load moment safety device, built in to the boom mechanism and thus linked to the lifting mechanism, cuts in if the permitted load moment is exceeded. The brochure writer realised the significance of the fact that the device acted when the load was exceeded and not ... as was the case ten years ago, at the point when the superstructurehas already tipped over! These load moment safety devices, although a small part of the overall crane, were very important in the development of cranes .目录起重机的雏形前言起重机械是被广泛地应用于各种物料的起重、运输、装卸、安装和人员输送等作业中现代工业生产不可缺少的设备。起重机是以间歇、重复的工作方式 , 通过起重吊钩或其它吊具起升、下降 , 或升降与运移物料的机械设备。起重机的雏形　　中国古代灌溉农田用的桔是臂架型起重机的雏形。14世纪，西欧出现