【作者】 任小中；

【导师】 邓效忠；

【作者基本信息】 江苏大学 ， 机械制造及其自动化， 2011， 博士

【摘要】 由太阳轮、行星轮和内齿轮组成的行星轮系被广泛应用于起重、建筑、矿山、汽车、能源等行业的机械传动中。硬齿面齿轮可以成倍提高传动装置承载能力和使用寿命,大大减小传动装置的尺寸和重量。在我国,要提高行星轮系的制造精度,增加它的承载能力,关键要解决硬齿面内齿轮的高效率磨削问题。由于传统的范成法很难解决硬齿面内齿轮的磨削问题,而国外制造的数控成形磨齿机价格昂贵,致使国内内齿轮加工厂家普遍采用插(拉)齿后氮化处理的齿面强化工艺。这种工艺不仅对齿轮材料有特殊要求,而且加工效率和精度均不高。尽管国外已有商品化的数控成形磨齿机,国内也有个别厂家开始研制,但对内齿轮成形磨削工艺及装备技术的研究报道却很少。为了改变我国成形磨齿机依靠进口的局面,促进我国齿轮制造业的发展,研究并开发出具有我国自主知识产权的成形磨齿机和成形磨削技术已经迫在眉睫。鉴于此,本文对内齿轮成形磨削工艺及装备技术进行了系统地研究。论文的主要研究内容如下：(1)基于模块化设计原理,进行了内齿轮成形磨齿机模块化设计。在分析内齿轮成形磨齿机功能的基础上,设计了机床的总体布局,划分了机床的各级模块。以Pro/E为开发平台,以Pro/Toolkit为二次开发工具,建立了成形磨齿机各级模块的全参数化三维模型库,开发了支持模块化设计的磨齿机CAD系统。在此基础上对机床的零部件进行了详细设计和合理选择。(2)对成形磨齿机关键零部件的结构进行了分析与研究。利用Pro/E三维建模功能对内齿轮磨齿机立柱进行参数化建模,利用ANSYS分析软件对其进行了静力和动态分析,探讨了不同筋板布局形式对立柱动态特性的影响,通过灵敏度分析找到影响立柱性能的主要参数,提出了新立柱的结构设计方案。对砂轮架的结构进行了有限元分析和改进,建立了砂轮主轴的有限元模型,并对该主轴进行了模态分析,计算出了砂轮主轴的临界转速。(3)研究了渐开线廓形砂轮的修整方法,研制了成形砂轮修整装置。基于渐开线形成原理,分别用“范成法”和“插补法”研究了渐开线廓形砂轮的修整运动,建立了各自的数学模型,并对两种方法的砂轮修整装置进行了概念设计。通过比较分析这两种方法的可行性和经济性,设计并制造出了基于“插补法”的砂轮数控修整装置。(4)开发了渐开线廓形砂轮数控修整插补软件。内齿轮成形磨削的齿形精度主要取决于成形砂轮的形状精度,如何利用数控技术来实现渐开线廓形砂轮的修整是内齿轮数控成形磨削的关键。研究了可适用于任意齿数、模数的渐开线轮廓的砂轮修整技术,对渐开线插补作了较为深入的理论分析,提出了以法向允差δ为插补精度指标,通过改变展开角增量值△θ的大小不断改变插补点的密集程度,使插补点个数既能满足所需的修整精度,又能保证较高的砂轮修整效率。以VC++为平台开发出了可用于磨削任意参数和精度齿轮的砂轮数控修整软件。该软件主要分为四个模块：齿轮参数输入和计算对话框模块、渐开线插补计算模块、渐开线修整路径动态模拟模块、数控代码输出模块。该软件还能根据待加工齿轮参数自动生成加工代码,由RS232接口传入数控机床并保存在程序存储器中。(5)分析研究了内齿轮成形磨削工艺。成形磨削是硬齿面齿轮精加工的一种方法。它借助成形砂轮的切削作用去除轮齿表面的多余金属,可全面纠正齿轮磨前的各项误差,使整个齿轮达到较高的加工精度和表面质量。磨齿工艺的选择及制定不仅影响磨齿效率,而且影响齿面的轮廓精度和表面粗糙度。本文基于所开发的成形磨齿机床,主要研究成形磨削中所涉及的砂轮选择与修整、磨削液的选择与浇注方法、磨齿余量、磨削用量的选择等工艺性问题。(6)分析研究了影响成形磨齿质量的因素,提出了提高磨齿质量的措施。磨齿质量涉及内容广泛,这里主要指的是齿形精度、齿距精度、齿面粗糙度、齿面磨削烧伤等。在分析磨前插齿精度的基础上,根据成形磨齿原理,着重分析了影响内齿轮成形磨齿齿形精度和齿距精度的主要因素,并提出了提高齿形精度和齿距精度的措施。从磨齿工艺参数、砂轮修整等方面分析了影响齿廓表面粗糙度、齿面烧伤的因素,并提出了解决问题的对策。(7)完成了数控成形磨齿机安装调试。机床的安装精度对机床的加工精度将产生直接影响。对于所研制的数控成形磨齿机来讲,由于采用了模块化设计,给整机装配带来了极大方便。重点要做好数控滑台以及数控回转台的安装与调整。数控滑台的安装精度直接影响到工作台的直线运动精度,对加工齿轮的齿向精度、周节累积误差都有较大的影响。滚珠丝杠副与导轨的平行度、丝杠螺母座与滑台的高度要求都很严,仅靠加工无法保证,必须选择合适的装配方法。数控回转台用来对齿轮进行分度,其分度精度直接影响齿轮的周节累积误差。在实际安装时,既要考虑消除传动误差,又要考虑减小运动阻力。(8)完成了渐开线廓形砂轮的修整试验和内齿轮成形磨齿试验。砂轮修整试验包括生成砂轮修整程序和砂轮修整。首先向砂轮修整软件系统输入被加工齿轮的基本参数,利用渐开线修整路径动态模拟模块对渐开线形成过程进行仿真,再利用生成的砂轮修整程序,选择合适的砂轮修整余量对砂轮分别进行粗修和精修。磨齿前要检查工件安装位置、回转台中心位置、砂轮架竖直方向的位置是否正确,然后手工输入加工程序,进行空试车运行,确保加工轨迹正确无误。最后进行磨齿加工。检测发现,磨削齿轮的齿形误差、齿向误差、周节累积误差均可达到6级精度要求。综上所述,本文较详细地研究了内齿轮成形磨削工艺与装备技术。创新性地研制出了一种内齿轮数控成形磨齿机和成形砂轮数控修整装置,提出了内齿轮成形磨削的数学模型和加工方案,开发了内齿轮数控成形磨削软件系统。磨齿试验结果表明,所研制的数控成形磨齿机结构简单,经济实用,加工精度、加工效率以及柔性均较高,不仅可以加工内齿轮,也可以加工外齿轮；不仅可以加工直齿轮,也可以加工斜齿轮。本课题的完成有助于改变我国成形磨齿机床依赖进口的局面,带动国内齿轮加工机床制造业的发展。更多还原

【Abstract】 The planetary gearing composed of sun gear, planet gear and internal gear is widely used in mechanical transmissions of crane industry, construction industry, mineral industry, automobile industry, energy industry and other industries. Equipped with hardened gears, the loading capacity and service life of transmission devices can be increased exponentially, and their size and weight can be decreased largely. At present in our country, in order to enhance manufacturing precision and loading capacity of planetary trains, the key is to realize the grinding of internal gears with hardened flanks. As it is difficult for generating method to machine the internal gears, and the CNC gear form grinding machines made in developed countries are very expensive, these make the domestic gear manufacturing factories find other ways to treat the internal gear with hard flanks. For example, after gear shaping or broaching, the internal gear is hardened by nitriding. Nitriding has the special requirements for the gear material and low processing efficiency. Because there is no any further finish machining after nitriding, it is impossible for the gears to have higher profile accuracy and loading capacity. Although there have been the commercial CNC gear form grinding machines in some developed countries, and a few of domestic companies have started to develop this kind of grinding machines, there is still very few report on the research of internal gear form grinding process and equipment technology.In order to change the situation that the gear form grinding machines rely on import from abroad, and promote the development of domestic gear manufacturing industry, it is urgent task to research and develop gear form grinding machine and technology owned the Autonomous Intellectual Property of P.R. China. For this reason, internal gear form grinding process and equipment technology are studied systematically in this dissertation. The primary research contents and accomplishments of this dissertation are as follows:(1) Based on modularization design principle, modular design of internal gear form grinding machine is completed. On the basis of function analysis, the layout of the internal gear form grinding machine is designed, and different modules of the machine are divided. Taking Pro/E software as developing platform and Pro/Toolkit as secondary development tool, a total parametric 3D modeling bank for each module of gear form grinding machine is established. A CAD system to support modular design of gear form grinding machine is developed. And then, the components and subassemblies of gear form grinding machine are designed in detail and selected rationally.(2) Analysis and research on the key components and subassemblies of gear form grinding machine are carried out.3D parametric model of the column of gear grinding machine is established by means of Pro/E. Both static analysis and dynamic analysis are performed by means of ANSYS software. The influences of different rib structures on the dynamic characteristic of column are investigated. The major parameters influencing on column’s performance are found by analyzing the sensitivity of structure parameters, and a new design plan for column is proposed. With the aid in finite element analysis (FEA), the original structure of grinding wheel frame is improved. The finite element model of wheel spindle is set up, and modal analysis on the spindle is done. The critical revolution of the spindle is also calculated.(3) Dressing of involute grinding wheel is investigated and wheel dressing device is developed. According to involute generating principle, the motions required in dressing involute wheel are studied based on "generation method" and "interpolation method" respectively. Mathematical models of two wheel dressing methods are established, and two wheel dressing devices are drawn correspondingly. By comparing the feasibility and economics of the two methods, NC wheel dressing device based on "interpolation method" is finally designed and manufactured.(4) The interpolation software for dressing involute grinding wheel is developed. The tooth profile accuracy of gear form grinding depends mainly on the profile accuracy of form wheel to be dressed. How to dress involute grinding wheel by means of NC technology is the key to the internal gear grinding. The wheel dressing technology suitable for involute profile with arbitrary tooth, module and base circle radius is studied. On the basis of analyzing involute interpolation, taking the normal tolerance 8 as the interpolation accuracy index, the density of interpolation points can be changed constantly with the change of developable angle incrementΔθso that the numbers of interpolation points can meet the requirements not only for interpolation accuracy, but for interpolation efficiency. Taking VC++as developing platform, the wheel dressing software system is developed, which can be applied for dressing involute grinding wheel used for grinding the gears with any parameter and accuracy. The software system consists of four modules:gear parameters input and calculation dialog block, interpolation accuracy calculation and control, dressing route simulation, NC machining code output. By means of this software system, NC machining code can be generated automatically according to the parameters of gear to be machined, and input into the CNC unit through RS232 interface.(5) Internal gear form grinding process is analyzed and researched. Gear form grinding is one of the finishing processes of gears with hard flank. It can remove the excess metals from tooth flank by means of form grinding wheel, and correct completely various errors existed in pre-grinding gear so as to have gear acquire higher machining accuracy and surface quality. The selection and formulation of gear form grinding process have an influence not only on the grinding efficiency, but on the tooth profile accuracy and surface roughness. Based on the autonomous developed CNC internal gear grinding machine, the issues on the selection and dressing of grinding wheel, the selection of grinding fluids, grinding allowance, and grinding variables involved in gear form grinding process are mainly discussed.(6) The factors influencing on gear grinding quality are analyzed, and the measures to improve gear grinding quality are put forward. Gear grinding quality includes many contents. Here means primarily profile accuracy, tooth spacing accuracy, tooth flank roughness, flank grinding burn, and so on. On the basis of analyzing gear shaping accuracy, some major factors influencing on profile accuracy and tooth spacing accuracy in internal gear form grinding are analyzed emphatically in light of gear form grinding principle, and the corresponding measures are proposed. The factors influencing on tooth flank roughness, flank burn are also discussed from gear grinding process, wheel dressing and gear material, the countermeasures to solve these problems are pointed out.(7) Installation and adjustment of CNC gear form grinding machine are completed. Installation accuracy of machine tool has direct influence on the machining accuracy. As to the CNC gear form grinding machine mentioned above, modular design makes the assembly of total machine very convenient. The emphasis is to install and set the NC slide and NC rotary table well. The installation accuracy of NC slide has direct influence on the linear motion accuracy. Therefore, it would have larger influence on the tooth alignment accuracy and accumulative pitch error. As the requirements for the parallelism of ball screw and nut to guide-way, and the distance from the centerline of nut seat to the slide bottom are very strict, it is difficult to ensure these requirements only relying on machining, proper assembly methods must be selected. NC rotary table is used for the indexing of gear. Its indexing accuracy has direct influence on the accumulative pitch error. In practical installation, both eliminating transmission error and reducing moving resistance are considered at the same time.(8) Involute wheel dressing test and internal gear form grinding test are completed. The wheel dressing test includes the generating wheel dressing program and wheel dressing. Firstly, basic parameters of gear to be machined are input into wheel dressing software system. Then, the involute forming process is simulated by means of involute dressing route simulation module. Lastly, the rough and finish dressing of grinding wheel are carried out by means of wheel dressing program generated in the software system. Before grinding the gear, the wheel dressing device, workpiece, center of rotary table, and grinding wheel frame etc. should be set to proper position. Then by inputting machining program manually through the operation panel, the unloading trial run must be done in order to ensure the grinding track correct. Lastly, gear grinding can be carried out. It is found by inspecting the ground gear that the precision with grade 6 can be met whether in tooth error, or tooth alignment error and pitch error.To sum up, internal gear form grinding process and equipment technology are researched in detail in this dissertation. Not only a kind of CNC internal gear form grinding machine and a wheel dressing device are researched and developed creatively, but the mathematical model for internal gear form grinding and machining plan are put forward creatively. A software system for internal gear form grinding is developed. Gear grinding tests show that the gear form grinding machine is simple in design, economical and practical, and has higher machining accuracy and flexibility. In reality, the grinding machine can be used to grind cylindrical spur and helical gears whether they are external or internal gears. The completion of this project would be helpful for changing the situation that gear form grinding machines rely on importation, thus promoting the development of domestic gear machine manufacturing industry.更多还原