【正文】 H type support leg can realize the larger span, the stability has obvious superiority, so China39。 the 6product of the performance indicators reached50 tons TADANO product performance indicators principleIn the lifting arm inside the following a rotation of the drum, it around the steel wire rope, wire rope through in the next section on top of the arm on the pulley, the upper section jib pull away, and so on. When retracted, the reel reverse recovery of wire rope, lifting arm by gravity back shrinkage. The rotation of the drum is driven by a hydraulic motor, so they can see the two tubing, but never as cylinder. In addition there are a number of truck crane telescopic boom is installed inside the plunger type oil cylinder is set, but the application of rare. Because the multistage plunger type oil cylinder is expensive, and the lifting arm loading will happen when the elastic bending, to adversely affect the service life of cylinder type of truck craneAutomobile crane of many kinds, its classification method also each are not identical, are: according to the weight classification: light truck crane ( from the weight of 5 tons ), automobile crane ( from the weight of515 tons), heavy duty truck crane ( from the weight of550 tons), super heavyduty truck crane (starting weight in more than 50 tons ). In recent years, due to the use of requirements, of which the weight tends to be improved, as has been to produce50100tons large truck crane. According to leg type: the breaststroke leg, X type, H type support leg leg. The breaststroke leg span is0? Only apply to small tonnage crane。3walking platform for all covered, the job on the car and maintenance。s professional quality is higher, the quality of export products feedback than in the past was reduced significantly, reflecting good product. This is Chinese automobile crane industry development has laid a good foundation crane product characteristics1luxury full cab and the control room with modern streamlined style。s new generation of automobile crane, lifting operation mode of operation, large area application pilot proportional control, has good adjustment performance and fine control performance, small operation force, is not easy to fatigue. Through the pilot scale handle to realize the proportion of conveying a variety of load of the stepless speed regulation, effectively prevent the hoisting operation of the two sliding phenomenon, greatly improve the lifting of the job security, the reliability and working efficiency. Part of the large car type crane 39。s automobile crane industry will bee a steady development, mercialize degree tall mature industry. Many experts think, the rapid development of the market, is China39。s automobile crane industry always walk the road of independent innovation, has its own clear sequence of development, especially in recent years, China 39。．起重運輸機(jī)金屬結(jié)構(gòu)設(shè)計[M]．北京：機(jī)械工業(yè)出版社，1997[5] 章宏甲，黃宜，[M].[6] 蔡福海. 全地面起重機(jī)發(fā)展現(xiàn)狀及其關(guān)鍵技術(shù)探討[R]. 工程機(jī)械與維修. [7] 周衛(wèi). 液壓汽車起重機(jī)吊臂同步伸縮機(jī)構(gòu)設(shè)計[M]. 工程機(jī)械. [8] [R]. 工程機(jī)械. [9] 楊又林. 起重臂用撓性伸縮機(jī)構(gòu)[M]. 起重運輸機(jī)械. [10] 郝振鐸. 大型伸縮臂式汽車起重機(jī)變幅鉸點的選取[M]. 工程機(jī)械. [11] 郭耀松. 起重機(jī)吊臂結(jié)構(gòu)的有限元分析[M]. 農(nóng)業(yè)裝備與車輛工程. [12] TANG Xiujun ,BU Xiaoping,ZHOU Bin, et al Research of moment limiter based on special controller for track crane[A]. Construction [13] Ministry of Machine Building .JB87161998 Safety regulations of tine mounted crane and track crane[S]. Institute of Mechanical standardization of Machinery Equipment of Ministry of Machine Building of China 199840青島理工大學(xué)畢業(yè)設(shè)計附錄1 Automobile crane is mounted on a mon automobile chassis or special automobile chassis on a crane, the driving cab and a lifting control room separated set. The crane has the advantages of good mobility, transfer quickly. Drawback is that work must support legs, cannot load driving, also do not fit in the soft or muddy ground work. Truck crane chassis performance equivalent to the same vehicle gross weight of truck, meet the technical requirements of road vehicles, and thus can be in various kinds of highway pass unimpeded. This kind of crane general with on off, two control room, operation must lend a supporting leg stability. Lifting weight range greatly, from 8tons to 1000 tons, chassis number of axles, from 2to 10. Is the largest, the most widely used crane type processChinese automobile crane was born in the 1039。此次畢業(yè)設(shè)計才會順利完成。除了敬佩武老師的專業(yè)水平外，他的治學(xué)嚴(yán)謹(jǐn)和科學(xué)研究的精神也是我永遠(yuǎn)學(xué)習(xí)的榜樣，并將積極影響我今后的學(xué)習(xí)和工作。武老師平日里工作繁多，但在我做畢業(yè)設(shè)計的每個階段，從查閱資料到設(shè)計草案的確定和修改，中期檢查，后期詳細(xì)設(shè)計，裝配草圖等整個過程中都給予了我悉心的指導(dǎo)。作為一個?？粕漠厴I(yè)設(shè)計，由于經(jīng)驗的匱乏，難免有許多考慮不周全的地方，如果沒有導(dǎo)師的督促指導(dǎo)，以及同學(xué)們的支持，想要完成這個設(shè)計是難以想象的。39致 謝大學(xué)生活一晃而過，回首走過的歲月，心中倍感充實，當(dāng)我寫完這篇畢業(yè)論文的時候，有一種如釋重負(fù)的感覺，感慨良多。在本次畢業(yè)設(shè)計中，在查閱資料之后，首先確定起重機(jī)伸縮臂的傳動方案和臂架的截面，然后對起重機(jī)主臂所需要設(shè)計的部分進(jìn)行計算，計算得出了三鉸點的位置數(shù)值，各節(jié)臂的長度值，液壓缸的主要尺寸；并參照QAY50汽車起重機(jī)的資料，選取截面形狀及尺寸。[ f ] ——變幅平面內(nèi)允許最大位移。[] ——材料許用應(yīng)力。設(shè)計中, 為保證臂的強(qiáng)度和剛度, 設(shè)定應(yīng)力STRESSM 和位移DEFLM 為狀態(tài)變量,控制應(yīng)力和位移的大小,即使臂滿足強(qiáng)度和剛度要求。狀態(tài)變量通常是控制設(shè)計的因變量數(shù)值,是設(shè)計變量的函數(shù),在ANSYS 中,這種函數(shù)關(guān)系不是顯式的,對狀態(tài)變量的約束構(gòu)成了約束方程。釋放繞銷軸中心回轉(zhuǎn)的轉(zhuǎn)動自由度（ROTX）。風(fēng)載荷加到吊臂側(cè)面上，而其它力則須加到相應(yīng)位置的節(jié)點上（或關(guān)鍵點上），為了使得這些加載點能成為節(jié)點，首先需要在此位置處創(chuàng)建硬點（Hard points），此外，由于鋼絲繩在臂頭的拉力及伸縮機(jī)構(gòu)鋼絲繩拉力等方向與整體坐標(biāo)系方向不一致，故還須旋轉(zhuǎn)這些節(jié)點坐標(biāo)系，以便于加載。為了達(dá)到此目的，首先要旋轉(zhuǎn)節(jié)點坐標(biāo)系，旋轉(zhuǎn)角度即為仰角θ，利用各節(jié)臂與滑塊在同一位置節(jié)點（Coincident Node）間的耦合，可方便地實現(xiàn)12個滑塊與吊臂對應(yīng)節(jié)點的耦合。首先考慮用ANSYS中的接觸單元來分析，但由于該算例中，單元數(shù)頗多，模型規(guī)模大，且有12處接觸（四節(jié)臂上下有12個滑塊），而接觸問題屬于非線性，求解過程必須反復(fù)迭代計算，因而計算量實在太大，另外，其準(zhǔn)確性也較差（實際結(jié)構(gòu)中的接觸特性尚不清楚），基于此，我們運用另外一種方法——節(jié)點自由度耦合技術(shù)來模擬滑塊與各節(jié)臂的接觸。整個網(wǎng)格劃分，控制單元形狀盡可能規(guī)則，避免形狀畸形。 各節(jié)臂筒體采用自由（free）及映射（mapped）方式劃分。若是對某些網(wǎng)格形狀不滿意，則可對這部分重新進(jìn)行劃分，因為重新劃分時，可刪除已有的網(wǎng)格，但不會刪除所指定的屬性。實體單元選用8節(jié)點的6面體單元Solid45。 (二) 單元選取及網(wǎng)格劃分 網(wǎng)格板采用板殼元Shell63來離散。各節(jié)臂的筒體由薄板構(gòu)成，取中面尺寸造型。 伸縮吊臂有限元模型建立 (一) 實體建模 考慮到吊臂的重量，在解算時由ANSYS自動計算。故我們應(yīng)用此法，并采用功能強(qiáng)大、技術(shù)上非常成熟的商用有限元軟件ANSYS為工具來進(jìn)行分析。吊臂伸縮采用一級伸縮液壓缸、雙繩排滑輪機(jī)構(gòu)（兩伸、兩縮）以實現(xiàn)二、三、四節(jié)吊臂同步伸縮。QAY50起重機(jī)采用四節(jié)伸縮式U形吊臂，各節(jié)臂之間可以相對滑動，靠它們搭接的上下滑塊來傳遞作用力。而對于吊臂而言，計算應(yīng)力、變形的精確模型應(yīng)為有限元模型D，即需要建立參數(shù)化有限元分析模型。吊臂設(shè)計中，為保證強(qiáng)度、剛度，可設(shè)定應(yīng)力和位移為狀態(tài)變量，控制應(yīng)力和位移的大小以達(dá)到吊臂的強(qiáng)度和剛度要求。因而吊臂的優(yōu)化設(shè)計歸結(jié)為其截面的參數(shù)優(yōu)化設(shè)計問題。 第5章 伸縮臂有限元分析在 ANSYS環(huán)境下進(jìn)行優(yōu)化設(shè)計，存在設(shè)計變量、狀態(tài)變量及目標(biāo)函數(shù)三類變量。便可得到旋轉(zhuǎn)平面中吊臂撓度相應(yīng)計算式。1