【作者】 谭越；

【导师】 马文星；

【作者基本信息】 吉林大学 ， 机械设计及理论， 2014， 博士

【摘要】 冲焊型液力变矩器是液力自动变速器（AT）的核心部件，AT作为目前车辆自动变速器市场占有率最高的产品，使得汽车行业成为液力变矩器最大的用户。近年来，国内各大汽车厂商先后推出了装备有AT的新型车，但其中的AT及其核心部件大多是依靠国外进口或者引进国外技术以后在国内组装生产。由于液力变矩器的结构形式和性能优劣对整车的动力性和经济性具有很大影响，因此，开发出具有我国自主知识产权的液力变矩器产品具有极好地应用前景。模具制造是冲焊型液力变矩器设计研发过程中的重要环节之一，其制造工艺和制造精度对液力变矩器工作性能有直接影响。在进行模具制造过程中，需要有效的控制板料冲压成形时的回弹。回弹是冲压成形过程中不可避免的现象。在板料的成形领域，它的存在造成零件的形状及尺寸与设计的要求不符，直接影响了冲压件的品质，如外观质量、装配性能和使用的可靠性等。液力变矩器零部件回弹的控制也成为其设计研发主要面临的问题。传统上普遍采用基于经验的现场“试错法”进行成形工艺参数的调整和模具型面的修正，这种方法通常需要花费大量的人力物力，并且生产周期长。因此，如何准确的预测液力变矩器零部件冲压回弹后的形状、设计出准确的型面用以补偿回弹，是实际生产中需要解决的难题。在冲焊型液力变矩器的设计过程中，结构的可靠性是保证其安全运行的关键。因此，在现有的材料、结构以及工艺条件下，液力变矩器叶片与内外环的焊接强度能否满足使用要求，需要进行校核。针对以上问题，本文以浙江省科技厅重大科技专项“轿车扁平化液力变矩器研制（2008C01036-4）”项目为依托，针对我国冲焊型液力变矩器在结构设计、模具制造方面所面临的关键技术性问题，对冲焊型液力变矩器冲压成形做了较为系统深入的研究。主要研究内容如下：1.变矩器冲压成形理论及基本参数测试以弹塑性变形理论为基础，对液力变矩器冲压成形有限元理论进行研究，并分析影响板料弯曲回弹的主要因素，为液力变矩器冲压成形的数值模拟研究提供理论依据；对液力变矩器叶片所用材料进行单向拉伸试验，得到材料的基本力学性能参数，为数值模拟中材料参数的选取提供依据；对叶片材料进行简单V型件的冲压成形数值模拟，并通过试验验证数值模拟方法的正确性，为后续对液力变矩器冲压成形的数值模拟奠定基础。2.冲焊型液力变矩器冲压成形数值模拟基于经验公式法和环量分配法，设计了YJH255型液力变矩器简化模型；为了提高材料的利用率，将有限元逆算法应用到液力变矩器的坯料展开计算中，得到冲压件展开料的形状和尺寸大小；针对液力变矩器冲压件的展开料进行冲压成形数值模拟，分析冲压件的成形结果，并对零件实际生产过程中可能出现的回弹量进行预测，为利用回弹规律进行模具补偿提供依据。3.叶片回弹补偿与模具设计冲焊型液力变矩器的叶片形状复杂，制造精度要求高。叶片的形状决定变矩器的性能，应保证实物模型与设计模型一致，因此需要对液力变矩器叶片的回弹量进行补偿。基于正交试验方法，对型面复杂的三维空间扭曲叶片进行冲压回弹试验，得到最优的成形工艺参数；利用模具型面补偿法对液力变矩器叶片进行回弹修正；最后对满足设计要求的液力变矩器叶片及内外环模具型面，使用三维造型软件UG对其进行参数化设计，并对模具进行快速三维造型，最后制造出液力变矩器实物。4.液力变矩器成形的检测与对比分析由于液力变矩器的叶片为空间扭曲曲面，为验证其回弹补偿方法的有效性，利用ATOS非接触式光学扫描仪对本文设计并制造出的液力变矩器样机进行扫描测试，检测成形精度；同时对液力变矩器进行外特性试验，检测该液力变矩器的性能。5.冲焊型液力变矩器叶片与内外环焊接强度分析基于单向流固耦合（FSI）分析技术，对本文设计的液力变矩器叶片与内外环进行焊接强度分析。利用流体分析软件FLUENT对变矩器工作腔内的流场进行CFD数值计算；然后将流场计算得到的作用在耦合面上的流体压力载荷，通过网格插值映射的方法映射到叶轮结构的表面；最后利用结构有限元分析软件ANSYS对液力变矩器叶轮结构进行FSI焊接强度计算。本文针对冲焊型液力变矩器冲压成形理论和数值模拟方法的研究，能够有效的解决实际生产中的技术难题，促进液力变矩器模具技术的进步，降低生产成本和缩短生产周期；为液力变矩器的制造提供理论指导意义与实用价值，为其新产品的开发提供借鉴，同时为我国汽车行业的自主研发奠定良好的基础。更多还原

【Abstract】 Stamping welded hydrodynamic torque converter is the core component ofhydrodynamic automatic transmission (AT), which is mostly applied in the market ofvehicles with automatic transmission. Therefore, in automobile industry, hydrodynamictorque converter becomes the largest user. In recent years, although domestic automobilemanufacturer has launched new cars that are equipped with AT, the AT and its corecomponents mainly rely on the imported product, and mostly apply foreign technologies toassemble before producing in China. Since the performance and structure of hydrodynamictorque converter have a great influence on the power performance and fuel economy ofvehicle, so developing a hydrodynamic torque converter with our own intellectual propertyrights has excellent application prospect.Die manufacture is a key step in the process of designing and developing stampingwelded hydrodynamic torque converter, and the process and accuracy of manufacturedirectly impact the working performance of hydrodynamic torque converter. During theprocess of manufacturing die, it is necessary for the developers to efficiently control thespringback, which is generated by sheet forming and is also an inevitable phenomenon. Inthe area of sheet forming, springback may cause difficulties of matching the size and shapeof parts under the designing requirement, this matter will also directly affect the quality ofstamping parts, such as the appearance quality, assembled performance, and reliability, etc.Therefore, the control of springback parts in hydrodynamic torque converter is the maindesign problem. Traditionally, researchers use the method called the scene of “trial anderror”-based on experiences to adjust the forming process parameters and amend the die-face, however, this method wastes lots of resources, and the production period is also toolong. Therefore, we mainly have two difficulties in the practical industry, one is how topredict the shape of hydrodynamic torque converter after springback, and the other is how todesign the die-face for compensating springback accurately.In the process of designing stamping welded hydrodynamic torque converter, thereliability of the whole structure is the key to ensure the secure operation. Therefore, in orderto test whether it reaches the requirements of hydrodynamic torque converter, we shouldcheck the welding strength of blade with core and shell based on the existing material,structure and designing condition.According to the above questions, this paper, relied on the projects “Development onflat hydrodynamic torque converter of car (2008C01036-4)” of Science and TechnologyAgency of Zhejiang Province, mainly focuses on the technical problem of designing andmanufacturing of stamping welded hydrodynamic torque converter, and will discuss deeplyabout the stamping forming of stamping welded hydrodynamic torque converter. The mainresearch contents contain:1. The stamping forming theory of torque converter and basic parameters testBased on elastic-plastic deformation theory, investigate the finite element theory ofstamping forming for hydrodynamic torque converter, analyze the main factors influencingthe bending springback of sheet metal, and also provide theoretical basis for the subsequentforming simulation of hydrodynamic torque converter; use the sheet tensile test on materialof making torque converter blade to get the basic parameters of mechanical properties ofmaterials, and then provide the evidence of the selection of material parameters in numericalsimulation; apply the torque converter blade material in the stamping forming numericalsimulation for the simple V type parts, and then test the certification of numerical simulationin order to lay a foundation for the following numerical simulation of stamping forming onstamping welded hydrodynamic torque converter.2. The forming simulation of stamping welded hydrodynamic torque converterBased on the empirical formula and the circulation distribution method, design a simplemodel of YJH255stamping welded hydrodynamic torque converter. In order to improve the utilization rate of materials, apply the finite element inverse algorithm to the blank unfoldingcalculation of hydrodynamic torque converter, and then get the shape and size of blankmaterial; numerically simulate the stamping forming of torque converter blank unfolded, andanalyze the forming results, and finally predict the springback that may appears in the actualproducing process, this would provide the evidence of using springback rules in die-facecompensation.3. The blade springback compensation and die designThe shape of stamping welded hydrodynamic torque converter blade is complicated, soit needs a high precision of manufacturing. The shape of the blade determines theperformance of torque converter and needs to be the same as the real product, so we need tocompensate the springback value of torque converter blade. To get the best forming processparameters, we test the springback value on three-dimensional space twisted blade byorthogonal test method; Use die-face compensation method on hydrodynamic torqueconverter blade to correct springback; Considering to meet the design requirements of thedie-face of blade, core and shell in a hydrodynamic torque converter, we use3D modelingsoftware UG to parametric design, and then fast generates3D models for the dies, finally, getthe real product of hydrodynamic torque converter.4. Test and comparative analysis the forming of hydrodynamic torque converterBecause the blade of torque converter is spatial distortion surface, so in order to verifythe effectiveness of the springback compensation method, we choose to scan and test thedesigned stamping welded hydrodynamic torque converter prototype by ATOS non-contactoptical scanner, and then test the forming precision. Meanwhile, we will also test the externalcharacteristics of the hydrodynamic torque converter, and then examine the performance ofthe hydrodynamic torque converter.5. The welding strength analysis of blade with core and shell on stamping weldedhydrodynamic torque converterBased on the fluid-solid interaction (FSI) analysis technology, we analyze the weldingstrength on the designed blade with core and shell of hydrodynamic torque converter. Firstly,numerical calculate CFD on flow field of torque converter working chamber by the fluid analysis software FLUENT; Secondly, apply the results about the fluid pressure load in thecoupling surface mapping onto the impeller structure surface by the method of gridinterpolation mapping; Finally, use finite element analysis software ANSYS to calculate theFSI welding strength of impeller structure of hydrodynamic torque converter.This paper discusses the stamping forming theory and numerical simulation methods ofstamping welded hydrodynamic torque converter. These theories and methods effectivelysolve the technical problems in production, promote the die technology of hydrodynamictorque converter, and also reduce production cost and cycle. Moreover, this paper hasimportant theory guiding significance and practical value to manufacture of stamping weldedhydrodynamic torque converter, and provides references for the development of newproducts of hydrodynamic torque converter, and also provides a better foundation for theindependent research in Chinese automobile industry.更多还原