【作者】 朱学明；

【导师】 林彬；

【作者基本信息】 天津大学 ， 机械制造及其自动化， 2010， 硕士

【摘要】 随着科学技术的发展,人们对机械设备的使用性能提出了越来越高的要求。传动机构作为机械系统的重要组成之一,其性能直接影响着整个机械系统的性能。齿轮传动是应用最广泛的机械传动形式之一,因此提高齿轮的传动精度、传动效率和传动平稳性,减小甚至消除传动噪声和振动,实现传动的平稳可控极其重要。本课题以一对承受双向载荷的精密齿轮副为例,研究通过消除齿轮副侧隙来实现传动的平稳可控。首先根据齿轮副的工况、性能和尺寸要求,确定了齿轮副消隙结构及其尺寸参数,进而应用有限元软件ANSYS的APDL语言编写程序建立精确的齿轮副参数化模型。调用ANSYS接触分析模块对不同预紧力下的齿侧间隙和齿面接触应力进行分析,得到参数随预紧力的变化规律,初步确定恒转矩下消除间隙所需的预紧力;分析了中心距偏差fa、轴线平面内平行度偏差fΣδ和垂直平面内平行度偏差fΣβ这三种装配误差对接触应力的影响,得到应力的分布和极值;调用ANSYS模态分析模块对齿轮副进行了模态仿真,得到前10阶固有频率和振型,分析了预紧力对模态的影响。从分析结果中发现,齿轮副正转时滑销自锁,很小的预紧力即可消除侧隙,反转时滑销未完全自锁,需要较大的预紧力才能消除侧隙。中心距偏差会改变齿轮副的重合度,正偏差对接触应力几乎没有影响,适量的负偏差可以改善齿间载荷分配。平行度偏差使齿轮偏载,导致齿向载荷分配不均,齿轮传动不平稳。齿轮副接触分析为装配公差的确定提供了依据;模态分析所提供的固有频率和振型,为齿轮副工作频率的选择提供了依据。总之,本文的研究成果为实现齿轮副传动的平稳可控具有重要的指导意义。更多还原

【Abstract】 With the development of science and technology, the performance of mechanical equipment is increasingly needed to be high. The transmission mechanism as an important component of the mechanical system, its performance directly affects the performance of the entire mechanical system. Gear transmission is the most widely used in mechanical transmission, thereby increasing the transmission precision, transmission efficiency and transmission smoothness of the gears, reducing or even eliminating transmission noise and vibration, achieving a smooth transmission control, is extremely important.In order to improve transmission performance of the precision gear pair under biaxial loading, backlash of the gear pair is eliminated in this paper. According to the condition, performance and size requirements of the gear pair, the structure to coordinate gap and size parameters are determined. APDL program of finite element software ANSYS is used to establish accurate parametric gear model. Tooth backlash clearance and tooth surface contact stress under different preload are analyzed by contact analysis module of ANSYS. The result with the change of preload is plotted. The preload under constant torque is determined. Influences of central distance deviation, parallelism of the axis plane and vertical plane on contact stress are also analyzed. Modal analysis of the gear pair is carried out by ANSYS modal analysis module. Former ten natural frequencies and modal shapes are obtained. Impact of preload on mode is also analyzed.It is can be founded from the analyzed results that when the gear pair clockwise rotates, a small preload can eliminate the backlash; when the gear pair anticlockwise rotates, a larger preload is needed to eliminate the backlash. Center distance deviation will change the coincidence degree of the gear pair. Positive deviation hardly affects the contact stress, and negative deviation can improve the load distribution between teeth. Parallelism deviation induce bias load between the gear pair, which result in uneven distribution of the contact stress and unstable gear transmission.The contact analysis results can be used to determine the assembly tolerance. Natural frequencies and mode shapes acquired by modal analysis are useful for determining the operating frequency of the gears. All the research results have an important guidance for smooth and controllable gear transmission.更多还原