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1、机械原理课程设计说明书自卸车倾卸机构创新设计学院：机械工程学院班级：组员：指导教师：二一三年一月四日摘摘要要我们组选择自卸车倾卸机构的创新设计作为课程设计的题目.为了完成课程设计,我们首先查找了关于自卸车倾卸机构的发展史,了解了自卸车的发展历程与现状.然后我们查找了关于自卸的国内外专利,并分析其机构,画出机构简图.知道了自卸车有各种不同的机构,并了解了现在常用的自卸机构以及自卸机构未来的发展趋势.为了创新设计,我们现场对常见自卸车的自卸机构拍照.分析机构,并进行了运动链的一般化,数综合,特定化和具体化等一系列过程.最后得出 27 个可能的机构简图.在进行比较时,我们选择了一个不是当前流行类型的

2、机构简图作为自己的创新设计.按对自卸车较为常见的要求:车斗最大倾角,机构纵深,液压缸伸缩距离,结构合理等,我们设计了创新机构的尺寸.在用inventor对其进行运动仿真后,发现结构运动平稳.然后我们又用matlab对机构进行建模,仿真.得出机构的角速度,角加速度等图形.发现机构角速度变化幅度不大,符合仿真动画,满足实际要求,因此,我们确定了我们的创新设计符合要求并将其作为最终的课程设计的方案.AbstractAbstractOur group chooses dump truck dumping mechanism innovation design as curriculumdesign q

3、uestions.In order to complete the course design,we first look for the dumptruck dumping mechanism about the history of the dump truck,understand thedevelopment course and present situation.Then we find about dumping domestic andforeign patents,and analyzes the mechanism,draw the mechanism diagram.Kn

4、ow thedump truck,there are all kinds of different organizations,and to understand thepresent commonly used self-discharginginstitutions and self-discharging mechanismthe future trend of development.In order to creative design,our site to the common dumpers self-dischargingmechanism photos.Body analy

5、sis and the kinematic chain of generalization,severalcomprehensive,specialization and shape and a series of process that.At last,wegive 27 possible mechanism diagrams.In comparison,we chose a not current populartype of mechanism diagram as their innovative design.According to the requirementsof the

6、more common to dump truck,car bucket maximum Angle of inclination,the agencydepth,hydraulic cylinder expansion distance,reasonable structure and so on,wedesign the innovation organization in the size of the inventor.The motion simulation,found that the smooth movement structure.Then weuse MATLABto m

7、echanism modeling,simulation.Draw mechanism of angular velocity,angular acceleration and angularvelocity change graphics.Find institutions range is not too much,in line with thesimulation animation,meet the practical requirements,therefore,we determine ourinnovative design meet the requirements as t

8、heir final course design scheme.目目录录一、题目简介.11.题目描述.12.原始数据和设计规格.2二、现有机构分析.21.文献综述.22.Literature Review.43.现有机构分析.6三、机构创新（Creative Mechanism Design Methodology）.171.Brief Diagram of the Prototype:.172.Generalization:.173.Number synthesis.174.Specialization.175.Particularization:.24四、尺寸设计.261.尺寸设计.262

9、.设计图.27五、机构分析与仿真.281.Inventor 仿真图像.282.Matlab 仿真过程.28六、总结.33七、Reference.34八、附录.351.MATLAB 程序代码：.35一、一、题目简介题目简介1.1.题目描述题目描述自卸车是一种通过车自身的倾卸机构，能够将车斗中货物倾卸出去的一种车。自卸车倾卸机构的创新设计就是对现有的自卸机构进行创新再设计，使其满足自卸的使用要求。平稳倾卸货物。如下图中，液压缸作为动力原件，液压缸的伸缩，通过六杆机构的转换，使车斗倾斜，达到倾卸货物的目的。自卸车图片自卸车图片 Pictures of a Dump TruckPictures of

10、a Dump Truck图图 1 1自卸车机构简图自卸车机构简图 Brief Diagram of the Dump TruckBrief Diagram of the Dump Truck图图 2 2DOF=3n-2Pl-Ph=3x5-2x7=12.2.原始数据和设计规格原始数据和设计规格（1）（2）（3）（4）选小车型设计，车斗长 5 米左右.为使货物倾卸完全，车斗最大倾角应在 4570 度，可以选择 60 度.单级液压缸，最大伸缩长度在 0.50.8m.机构纵深约为 0.5m.二、二、现有机构分析现有机构分析1.1.文献综述文献综述最早的自卸车是以马拉的形式的二轮装卸车，货物重心在二轮车

11、的轮轴上，当装载货物时，只需要放到轴上就可以了，货物前方用绳子勾住固定；卸载时倾卸车即可。这种二轮车曾用在开放矿场，用马匹拉着在铁轨上行走。1900 之后，一种四轮的马拉式平板自卸车诞生，它带有一个矩形货物箱，通过车前的绳子来实现倾卸。早期的马拉式自卸车早期的马拉式自卸车最早出现的自卸车车身是根据装卸重心位置的原则设计的，这种车最早出现在 1904 年，那时曼式重力倾卸机构在英国出现。液压倾斜机构自卸车液压倾斜机构自卸车液压力学运用在较早的马拉式自卸车上，根据记载表明，一种最早的液压倾斜机构运用在罗伯逊汽车上，它带有一个液压起重机，可以从汽车的发动机或者一个独立的蒸汽机里获得动力。Alley&

12、McLellan of Glasgow在 1907 年发明了早期的依靠蒸汽驱动的液压倾斜机构。履带式拖车履带式拖车在 19 世纪 20 年代中期，履带式拖车牵引轮式自卸车迅速流行。有时拖车可以拉两到五个附加拖车，很多公司开始发展可附加式拖车。最早的拖车是运行在轨道上的，但是当速度越来越受到限制时，开始使用轮胎来提高速度。这种轨道式拖车的发明者有 Euclid,JamesHagy,LaPlant-Choate,Rex-Watson,and Streich 和 Western。EuclidEuclid 自卸车自卸车Euclid 是自卸车发展的先驱者。George Armington 的儿子 Geo

13、rge Armington Jr.设计和制作了两种对世界自卸车有重大意义的发明，包括现代重型越野卡车和轮式拖车置底倾斜车。1934 年，这个公司发明了 10/11 吨级自卸车，名为Trak Truk.。它是第一个用来重型越野服务的后卸式自卸车，后来又发明了 15 吨级的自卸车，得到很大的改进。1919 世纪世纪 5050 年代的自卸车年代的自卸车到了 19 世纪 40 年代，自卸车的科技发展达到了一个新的高度，截至 19 世纪 50 年代，美国已经发明了置底式自卸车，1951 年，Euclid 公司制作出世界上最大的自卸车 1LLD。1954年 Komatsu 公司制作出时速为 42 千米净载

14、重为 13.60 吨的轮式自卸车。1958 年，自卸车市场上最大马力的单独发动机为 AP40，可达 600 马力。Ralph H.KressRalph H.Kress 和和 HaulpakHaulpakRalph H.Kress以他发明的前置式自卸车，重型越野自卸车在矿场的运用而闻名于整个自卸车的世界。1955 年，作为 WABCO(现在是 Komatsu)的创始者，他致力于可缩短轴距拥有深、斜、平特点的车身的设计，它就是 Haulpak，被视为量子发展设计。最早的 Haulpak 于 1957 年在市场上出现，它可以有 32 吨级的净载量，后来发展为 75 吨级。这些最早的自卸车吨级范围为

15、25 到 32 吨级，由于太小而广泛应用于矿场。Haulpak 最终由于在尺寸上的发展，成为表面矿场工业的选择。专利综述专利综述目前，自卸车从单纯的 5 吨自卸车逐渐向更高吨位的方向发展，举升机构也从简单的单级缸中置直顶式、多级缸中置直顶式向单级缸连杆组合式、多级缸前置直顶式的方向发展。液压倾斜机构是自卸车的核心，是判别自卸车优劣的首要指标。不同的举升机构，有不同的车型定位和市场定位。从美国专利局所查找的专利中我们可以看到大部分自卸车为单杠连杆组合式，例如US2849255,US3172703,US3620458 orso.US4036528。US6382731 运用多级缸中置直顶式。下面是各

16、个形式举升机构的优缺点。下面是各个形式举升机构的优缺点。单级缸中置直顶式举升机构是最早出现的举升机构，机构简单，紧凑，受力直观，而且成本低廉，在载重量为 5 吨或者 5 吨以下的自卸车中普遍采用。US4036528 运用此机构。多级缸中置直顶式举升机构为了改善单级缸直顶式举升机构的弱点，多级缸中置直顶式举升机构应运而生。它极大改善了油缸和副车架的使用环境，使油缸和副车架的手里很小，使整个液压系统的使用寿命大大延长。并且，由于多级缸是套筒式的结构，内泻量小。缺点是在布置上比较困难，液压系统过于复杂。在国内一般不被使用。专利 US4056283。单级缸连杆组合式举升机构有升平稳，超载能力强，系统液

17、压性能好等特点，因而被各大汽车改装厂采用，通过对四杆机构的优化设计，可以设计出多种连杆组合式机构。马进里式和油缸浮动式采用较多，其他由于具有缸径大，油缸行程短等因素采用过的较少。专利 US4168861。多级缸前置直顶式举升机构主要由一支多节缸组成，行程大 56 米，可以把重心将到最低，极大的改善了车辆的稳定性。由于该机构受力最简单，最省力，因此，采用多级缸前置直顶式举升机构的自卸车是今后重型自卸车的发展方向。但是有两点缺点，一是成本最昂贵，二是它的油缸行程过，三是控制系统过于灵敏。目前国内生产这种机构的不多。专利US5033794,US6382731。国内自卸车发展前景国内自卸车发展前景目前

18、国内自卸车发展主要受到两个问题的影响：大重力重心和重型载重。国内大部分自卸车运用了单级缸连杆组合式举升机构，在发展趋势为多级缸前置直顶式举升机构的前提下，尽管国内运用很少，但是我们相信，在不久的将来，它一定会迅速发展起来。2.2.Literature ReviewLiterature ReviewThe very first version of a dump truck used to haul and dump material was nothingmore than a simple dump body style cart drawn by horses.It would have

19、consisted ofa two-wheeled cart hinged图图 3 3to the axle with the center of gravity,when loaded,just behind the axle.The loadedfront body was hooked,and when unlatched,would dump.These carts were used in openmines and pulled by horses along a railway track.After 1900,a four-wheeled horse-drawn flatbed

20、 wagon with a rectangular bodylifted with a hand hoist in the front was employed.Early Truck Mounted Dump BodiesEarly Truck Mounted Dump BodiesThe earliest versions of truck mounted dump bodies relied on the principle ofgravity for dumping.Some of the first trucks with dump bodies designed on thispr

21、inciple appeared as early as 1904 when the Mann gravity dump was built in England.Hydraulic Dump BodiesHydraulic Dump BodiesHydraulics was being incorporated into truck mounted dump bodies relatively earlyon.Records show that one of the first hydraulic dump bodies was the Robertson SteamWagon with a

22、 hydraulic hoist that received power from the trucks engine or anindependent steam engine.Alley&McLellan of Glasgow developed another earlyhydraulic dump body in 1907 that was power-driven by steam.Crawler Tractor-trailersCrawler Tractor-trailersIn the middle of the 1920s,crawler tractors pulling he

23、avy dump trailers mountedon wheels or tracks were becoming increasingly popular.Sometimes crawlers would pulltwo to five attached trailers.Companies began developing wagons specificallydesigned for attachment to crawler tractors.The first versions were mounted on tracks;however,when speed restrictio

24、ns posed a problem,the wagons were mounted on wheelsto improve speed.Manufacturers of such trailers and haulers included Euclid,JamesHagy,LaPlant-Choate,Rex-Watson,and Streich and Western.Euclid Dump TrucksEuclid Dump TrucksEuclid was a pioneer in the development of dump trucks.George Armington Jr.,

25、son of founder George Armington,was a hydraulics designer and made two significantcontributions to the world of dump trucks.These included the modern heavy dutyoff-highway truck and the wheel tractor bottom dump wagon.In 1934 the company introduced its 10/11-ton dump truck called the Trak Truk.It wa

26、s the first rear-dump truck that was designed for heavy-duty off road service.This was followed up in 1936 with the companys 15-ton Model IFD truck that featureda diesel engine,modern drive line,planetary final drives,leaf-spring suspension,and pneumatic tires.The truck replaced heavy,gasoline power

27、ed chain drive Macktrucks that had previously been used for standard work in construction and miningoperations.Dump Trucks in the 1950sDump Trucks in the 1950sBy the 1940s the technological development of dump trucks had reached its peak.In the U.S.,bottom dump trucks were already dominating earthmo

28、ving sites by the 1950s.The decade continued to mark a proliferation in the manufacturing of dump trucks.In 1951,for example,Euclid produced the worlds largest dump truck when itmanufactured the 1LLD.In 1954 Komatsu built the first dump truck on wheels thattraveled at 26 miles(42 km)per hour and had

29、 a 13.60-ton payload.In 1958,the 600horsepower AP40 Auto car was the largest single engine dump truck on the market.Ralph H.Kress and the HaulpakRalph H.Kress and the HaulpakRalph Kress is perhaps best known in the dump truck world for pioneering andbringing dump truck technology to the forefront,in

30、 particular,heavy-duty,off-roaddump trucks used in mining.In 1955,as a consultant for WABCO(now Komatsu),he was instrumental inconfiguring a dump truck that incorporated a short wheelbase and had a high angleof turn with a deep,sloped,flat body known as a Haulpak and was viewed as the“quantum advanc

31、e in design”with its hydro-pneumatic“Hydrair”struts.The first versions of the Haulpak were made available to the market in 1957featuring 25-to 32-ton payload capacities and were eventually marketed and used astractors to pull supplementary 75-ton trailers.These earlier versions,ranging from25-to 32-

32、ton range capacity,were too small initially to be used in open pit minesbut gained acceptance from contractors.Eventually Haulpak grew in size and becamethe dump truck of choice in the surface mining industry.The Haulpak would exist asthe standard to which other off-highway dump trucks would come to

33、 be designed.3.3.现有机构分析现有机构分析（1 1）专利综述）专利综述 Patent ReviewPatent ReviewThe dump truck,as one the largest special vehicles,is developing from the 5tdump truck to more tons.The core of a dump truck is the lifting mechanism,whichdevelops from the single cylinder centrally-mounted straight top type and t

34、hemultistage cylinder centrally-mounted straight top type to the single cylinderconnecting rod combined type and the multistage cylinder lead straight top type.From the patents among the searching results from the US patent and trade markoffice,we can see that most of the trucks are designed with th

35、e single cylinderconnecting rod combined type such as US2849255,US2849255,US3172703,US3172703,US3620458US3620458 or so.US4036528US4036528uses the single cylinder centrally-mounted straight top type.US6382731US6382731 uses themultistage cylinder lead straight top type.Here are some advantages and dis

36、advantages of the four type of the dumpingmechanism:The single cylinder centrally-mounted straight top typeThe single cylinder centrally-mounted straight top type it is the pioneerof the lifting mechanism of the dump truck.Its structure is very simple and tightand its cost is low,but its load is ver

37、y small so that it is used as the trucks below5t.It is widely used as light-weight trucks,for example Dongfeng 3092F uses thislifting mechanism.See Patent:US4036528US4036528.图图 4 4The multistage cylinder centrally-mounted straight top type it improves thedisadvantages of the single cylinder centrall

38、y-mounted straight top type.It improvesthe condition of the cylinder and the frame to extend their lifetime and reduces theinside discharge of the cylinder.But the framework design is difficult.It makesthe hydraulic system complex and costs a lot,so it is not commonly used.See Patent:Patent:US405628

39、3US4056283.图图 5 5The single cylinder connecting rod combined typeThe single cylinder connecting rod combined type it has the stable liftingability,strong overloading ability and good hydraulic characteristics.It can bechanged into different style through changing the four-bar linkage.Mallory typeiso

40、ne of the types and widely used in China because of the characteristics of smallcylinder diameters and long cylinder routes.But some types is not widely used becauseof big cylinder diameters and short cylinder routes.See Patent:US4168861 Patent:US4168861.图图 6 6TheThe multistagemultistage cylindercyl

41、inder leadlead straightstraight toptop typetype is made up of one multistagecylinder whose route can be 5 to 6 meters.It is the simplest lifting mechanism andlargely improves the stability of the truck.It is the development direction of thedump truck.But its cost is the most expensive,which restrict

42、s its development inChina.See Patent:US5033794,US6382731.Patent:US5033794,US6382731.图图 7 7The future of Dump Trucks in ChinaThe future of Dump Trucks in ChinaMost of the dump trucks in China use the single cylinder connecting rod combinedtype,from the single cylinder centrally-mounted straight top t

43、ype and the multistagecylinder centrally-mounted straight top type.The trend of development is themultistage cylinder lead straight top type and the type will be developed,but wecant see a lot in China.We believe in the distant future it can quickly be developedand used in our country.The front mult

44、i-level cylinder lifting mechanism is the leading direction ofdump truck manufacturing.For now,the dump trucks in our country are bothered bytwo main problems:high gravity center and heavy dead weight.To overcome these twoobstacles,the younger generation and the technical engineers need to work hard

45、 toimprove the competing ability of our production.All in all,the key point is to improve the quality of our products.（2 2）专利列表）专利列表 Patent ListPatent ListPatent No.App TimePatent NameInventorDrawing FiguresBrief DiagramThe TypesLIFTINGMECHANISMUS20945211935.10.11FOR DUMPBODIESF.BISZANTZ etalInventi

46、onPatent;Eight-barLinkageHYDRAULICACTUATINGUS24492021946.11.8MECHANISMFOR DUMPTRUCKSClaims.(Cl et alInventionPatent;Four-barLinkageDUMP BODYUS25937761950.3.21TILTINGMECHANISMCharles E.Margala et alInventionPatent;Six-barLinkageHOISTMECHANISMUS28492551955.8.16FOR DUMPTRUCKSGerald J.Paskeret alInventi

47、onPatent;Six-barLinkageDUMPUS31727031963.6.14MECHANISMFOR TRUCKSJoan A.ByerInventionPatent;Six-barLinkageLATERALSTABILIZINGUS35128361968.10.9MEANS FOR ASEMI-TRAILERDUMP BODYAnthony Policfaet alInventionPatent;Eight-barLinkageALBERT RATHUS36204581970.4.21XYSteel ProductsLtd.Preston et alUtilityModelP

48、atent;Six-barLinkageTruck withUS40365281975.10.14tiltable bodyHeinrichLangendorfInventionPatent;Four-barLinkageLiftingUS40493161976.1.29mechanisms fortruck bodiesMarino PanedaOrdonezInventionPatent;Six-barLinkageInventionUS40521051976.4.9Truck hoistWalter MoePatent;Six-barLinkageTruck bed tiltingUS4

49、0662961976.12.28mechanismLouis M.Ray,Jr.et alInventionPatent;Six-barLinkageTruckUS40562831977.1.25constructionRobert MarvinPowUtilityModelPatent;Six-barLinkageDump-hoistUS41688611978.2.6conversionsystemOllie J.CarrollUtilityModelPatent;Six-barLinkageUtilityUS43020501979.10.17Truck hoistEldon D.Jones

50、ModelPatent;Six-barLinkageUtilityUS43826321982.6.10Dumping vehiclestabilizer systemCharlie C.PittsModelPatent;Six-barLinkageLift mechanismUS45317801982.9.3for a dump truckBruce M.BoczkiewiczUtilityModelPatent;Six-barLinkageScissor frame liftUS45925931984.5.4apparatus fordump trucksGlenn L.ChannellIn

51、ventionPatent;Six-barLinkageMinimum profileUS50488961988.4.20hoistGlenn L.ChannellUtilityModelPatent;Six-barLinkageUtilityUS50337941990.10.18Securing devicefor dump truckHenry L.VickModelPatent;Four-barLinkageApparatus forloading andUS52036681991.6.6unloading of acontainerstructure or otherloads.Laz

52、ar MarmurFree rangingbi-directionalUS51953851991.10.28hydraulicdumpingmechanismJerome A.JohnsonUtilityModelPatent;Six-barLinkageUtilityModelPatent;Six-barLinkageScissor frame liftUSRE347331992.8.5apparatus fordump trucksGlenn L.ChannellUtilityModelPatent;Six-barLinkageHoistUS55139011994.3.14mechanis

53、mFred P.Smith etaInventionPatent;Eight-barLinkageUtilityUS59677331997.12.12Hydraulic tilttrailerRussell CashModelPatent;Six-barLinkageUtilityUS61565961999.3.11Truck hoistEldon D.JonesModelPatent;Six-barLinkageLoad haulingvehicle withUS63827312000.6.26sidewall raisingand loweringmechanismMichael Slut

54、z etalUtilityModelPatent;Six-barLinkageUtilityUS66631852001.11.13Tipping trailersRhys WilliamRichardsModelPatent;Six-barLinkageUtilityUS77709802007.5.1Dump vehicleJames P.Godwin,Sr.et alModelPatent;Four-barLinkageUtilityUS75239942007.6.20HoistEldon D.JonesModelPatent;Six-barLinkageRefusecollectionUS

55、76952372008.8.8vehicle andlifting apparatusthereforKosti ShirvanianUtilityModelPatent;Six-barLinkageUS81573162010.1.29Translatingcargo bedHarlan J.BartelInventionPatent;Fourteen-barLinkage三、三、机构创新（机构创新（Creative Mechanism Design MethodologyCreative Mechanism Design Methodology）1.1.Brief Diagram of th

56、e Prototype:Brief Diagram of the Prototype:2.2.Generalization:Generalization:The prototype is a six-bar linkage,the kinematic chain can be regeneratedinto”Stephensons linkage”:3.3.Number synthesisNumber synthesisThere are only two effective ones called Watts linkage and Stephenson slinkage Stephenso

57、n Stephensons linkage Watts linkage Watts linkages linkage4.4.SpecializationSpecializationRequirements and constrains:Requirements and constrains:（1）One link has to be the body(ground link).（2）The box has to be a side link and the linkage has to be a Revolute Joint.（3）One link has to be the driving

58、link;considering the demand of huge power,the driving link must be hydraulic.（4）All linkages have to be Revolute Joints except the driving link(the hydrauliccylinder).（4）Box,driving link and the ground could not be in the same kinematic chaincircuit to avoid four-bar linkage which may affect lifting

59、 quality and stability.A A：Following are the 9 possible solutions according to 1 and 2Following are the 9 possible solutions according to 1 and 2：车斗车斗车身车身a)b)a)b)车身车身车斗车斗c)d)c)d)车身车身车斗车斗e)f)e)f)车斗车斗车身车身车斗车斗车身车身车斗车斗车身车身车斗车斗车斗车斗B B车身车身车身车身 g)h)g)h)车身车身车斗车斗i)i)B B：Driving link(Prismatic pair)Driving li

60、nk(Prismatic pair)Following are the 9 possible solutions according to 3,4 and 5:Following are the 9 possible solutions according to 3,4 and 5:车斗车斗车斗车斗底盘底盘底盘底盘A1 A2A1 A2车斗车斗底盘底盘A3 B1A3 B1车斗车斗底盘底盘B2 B3B2 B3车斗车斗底盘底盘B4 C1B4 C1车斗车斗底盘底盘车斗车斗底盘底盘底盘底盘车斗车斗底盘底盘底盘底盘车斗车斗车斗车斗C2 C3C2 C3车斗车斗底盘底盘D1 D2D1 D2车斗车斗底盘底盘D3

61、 D4D3 D4车斗车斗底盘底盘车斗车斗底盘底盘底盘底盘车斗车斗底盘底盘车斗车斗E3 E4E3 E4车车斗车斗底盘底盘底盘底盘车斗车斗底盘底盘车斗车斗底盘底盘 E1 E2 E1 E2 F1 F2 F1 F2车斗车斗车斗车斗底盘底盘底盘底盘 F3 H1 F3 H1车斗车斗车斗车斗底盘底盘底盘底盘H2 H3H2 H3底盘底盘车斗车斗底盘底盘 I1 I2 I1 I2车斗车斗底盘底盘车斗车斗 I3 I35.5.Particularization:Particularization:Following are the particularization of A1,D1 and F2Following

62、are the particularization of A1,D1 and F2图图 8 A18 A1图图 9 D19 D1图图 10 F210 F2四、四、尺寸设计尺寸设计1.1.尺寸设计尺寸设计以机构简图以机构简图 F2F2 作为创新设计的机构。作为创新设计的机构。D2 2C CE E1 14 43 3B B图图 1111选取选取 F2F2 作为创新设计的机构的优势：作为创新设计的机构的优势：（1）可以通过较小的液压缸行程获得较大的车斗角度变化（2）机构纵深较小，便于整车重心下降，提高产品竞争力（3）主动件等效力臂较长，在相同液压缸驱动力下力矩较大，机构负载能力强（4）经过估算发现，车斗

63、举升角速度平稳，卸货稳定A AF F2.2.设计图设计图D DL2L2最终位置最终位置C CL1L1L4L4E EA(A)A(A)L3L3B(B)B(B)液压杆液压杆DDEE初始位置初始位置H H图图 1212F(F)F(F)CC参数选择：参数选择：（1）车斗初始位置水平,为了使重物倾斜完，倾角需要 45至 70,在创新机构中选择最大倾角为（2）根据实际车的尺寸大小,按车斗长 4.8m,选择中间作为机构力的作用点,因此选取车斗的一半 L1=2.4mL1=2.4m（3）自卸车要求建造纵深尽可能小，所以使 B 点与 A 点在同一水平位置，F 点与 AB 所在水平位置高度差，即 BH 尽可能小。按一

64、般自卸车常见尺寸选择建造纵深为 0.4m。由图可知连杆 L2 大致为 0.5m,在没有精确要求的情况下，可选择 L2=0.5mL2=0.5m（4）由 L4L1sin60-L2=1.578m.为了使车斗在提升过程中受力较大，需要连杆 L2 与车斗形成较大的锐角。所以选择连架杆 L4=1.8m。此时可取 BE=0.8mBE=0.8m，L3=0.8mL3=0.8m（4）采取一级液压伸缩机构，所以有 EF=2EF，由 EE=1.06m,取 EE 垂直于 EF，则计算得 E EE=0.61mE=0.61m，EF=1.22mEF=1.22m。同时可以计算得到 BH=0.48mBH=0.48m，FH=0.2

65、2mFH=0.22m（5）由公式：L1cos60+L2cos2=L4+L3cos3L1=L2sin2+L3sin3（6）解得：2=56.41，3=67.92。此时液压缸行程等于液压缸初始长度 0.61m五、五、机构分析与仿真机构分析与仿真1.1.InventorInventor 仿真图像仿真图像图图 1313液压杆速度为 3cm/s，图示为车斗前端一点的位置，速度及加速度图像。图中显示速度和加速度基本不变，所以可以看出车斗运行平稳，故该创新机构符合实际要求。2.2.MatlabMatlab 仿真过程仿真过程由液压杆和 L4 杆所在四杆机构四杆机构分析出 L4 水平角（逆时针旋转）与液压杆长 g

66、anlength关系 F1：F1F1（液压杆长（液压杆长 ganlengthganlength）=L4=L4 水平角度水平角度再由 L4 杆和车斗 L1 杆所在四杆机构四杆机构分析出两者水平角关系 F2：F2F2（L4L4 水平角）水平角）=L1=L1 水平角水平角F1 和 F2 关联得到液压杆长 ganlength 和 L1 水平角的关系 F3：F3F3（液压杆长（液压杆长 ganlengthganlength）=L1=L1 水平角水平角根据 F3F3，以及压杆长压杆长 ganlength=ganlength=液压杆伸缩速度液压杆伸缩速度 v*v*时间时间 t t，得到 L1 水平角-时间 t 关系F4，并做出拟合曲线（单次升程使用 plotfit 函数线性拟合线性拟合，全程使用cftool 拟合工具中的8 级傅立叶拟合傅立叶拟合）：F4F4（时间（时间 t t）=L1=L1 水平角水平角即即角度角度-时间函数，作图时间函数，作图一次求导（diff 函数）即可得到角速度角速度-时间函数时间函数，作图，由速度=角速度*臂长可得车车斗中心铰接处线速度斗中心铰接处线速度-时间图时间图二次求