全文总字数：11754字
1. 研究目的与意义（文献综述）
dumptruck is a special vehicle that uses the engine power to drive the hydrauliclifting mechanism, tilts the car at a certain angle to unload the cargo, andrelies on the self-weight to resetit
with the development of dump truck product technology, thelifting mechanism structure is also increasing. as one of the important workingsystems of dumper, its design quality directly affects the performance of dumper.the inclinedmechanism should have good dynamic performance, balance and coordination ofunloading process, and meet the requirements of compact structure, safety and reliability.on dump trucks,hydraulic lifting mechanism is widely used now. commonly used lifting mechanismcan be divided into two categories: direct push type and connecting rodcombination type. according to the different position of the oil cylinder, itcan be divided into two types: the oil cylinder center type and the oilcylinder front type. according to the installation characteristics of oil cylinder,the combined lifting mechanism of connecting rod is divided into severalstructural types, such as the amplifying type of connecting rod pushingforward, the balancing type of lever pushing forward and the floating type ofoil cylinder. in the oil cylinder mid-mounted lifting mechanism, the oilcylinder is supported in the middle of the carriage. in the oil cylinderfront-mounted lifting mechanism, the oil cylinder is supported in the front ofthe car, the lifting force of the oil cylinder is small, the oil cylindertravel is large, often used in heavy dump trucks. the oil cylinder forward pushconnecting rod amplifying lifting mechanism is connected with the bottom plateof the car through the triangle plate. the lifting fulcrum of the car is closerto the front of the car. the car is in a good condition of stress andstability. push lever balanced before oil cylinder lifting mechanism, throughthe pull rod connected to the platform floor, car lifting protection is closeto the front of the car, the stress of the carriage is good, good start, butinstitutions triangle connecting rod geometry size is larger, structure iscompact, swinging angle of cylinder is larger, working stroke is bigger,hydraulic piping layout. the oil cylinder floating lifting mechanism, one endof the oil cylinder is directly connected to the floor of the car, the otherend is not fixed on the frame, but can move with the car flipped. the pull rodof this structure is directly connected with the floor of the car, and thelifting fulcrum is closer to the front of the car. however, the structure islarge in geometry size, not compact in structure, and the cylinder swing angleis large in lifting process, which makes it difficult to arrange the hydraulicpipeline. if different types of lifting mechanism can be equipped to thecorresponding dump truck according to their respective characteristics, boththe working performance of the dump truck and the use efficiency of the liftingmechanism will be greatly improved. therefore, how to choose the right liftingmechanism has become an important problem in dumper design. direct push liftingmechanism is widely used in mining automobiles in china.
according to thedifferent uses of the dumper bodies can be roughly divided into: ordinaryrectangular bodies and bucket bodies. the ordinary rectangular dumper bodies isused for bulk cargo transportation, and the rear plate is equipped withautomatic opening and closing mechanism to ensure the smooth unloading ofgoods. bucket cars are suitable for the transport of goods with large particlesize such as large stones. considering the impact of goods, the design shape ofthe cars is more complex and the materials are thicker. some models weld anglesteel to the bottom plate to increase stiffness and shock resistance. due tothe heavy weight of the carriage, it is necessary to carry out effectiveoptimization design to reduce its weight.by reducing the deadweight of the carriage, the power, economy and safety can be improved to acertain extent. we can reduce the weight from the use of lightweight materialsand computer simulation optimization. in europe, dumpers are mostly designedwith lightweight materials such as aluminum alloy, high-strength steel, plasticand conforming materials. at present, various automobile enterprises have takenthe application of the above-mentioned lightweight materials as an importantindicator to measure the level of automobile manufacturing technology and newmaterials development.
2. 研究的基本内容与方案
1、the basic content of the design;
（1）determinationof main size and mass parameters;
1）selection of chassis: according to the ratedloading mass of the design, the performance of the truck chassis of themanufacturers is compared, the truck chassis model of the second class isselected, and the parameters such as wheel base, wheelbase, approach angle anddeparture angle are determined.
3. 研究计划与安排
（1）the first week of the 8th semester: project design, literatureretrieval, and completion of the proposal report;
（2） week 2-3 of semester 8: foreign language translation and datacollection;
（3） week 4-6 of semester 8: design calculation and sketch drawing;
4. 参考文献（12篇以上）
1.乔维高. 专用汽车结构与设计[m]. 北京大学出版社, 2010.
2.史建军, 赵海艳. 我国自卸车市场结构分析及发展趋势展望[j]. 重型汽车, 2016, 000(003):35-36.
3.尹雄武. 轻型自卸车举升机构的优化设计[j]. 专用汽车, 2003(05):16-17.
