节点文献
珩磨气动测量系统中磨头测量元件优化设计
Honing Pneumatic Measuring System Grinding Head Measuring Element Optimization Design
【作者】 杜敏娟;
【作者基本信息】 兰州理工大学 , 机械制造及其自动化, 2012, 硕士
【摘要】 本课题来源于“高档数控机床与基础制造装备”科技重大专项,主要研究高档数控珩磨机气动测量系统中磨头测量元件优化设计,通过对气动测量系统的静态实验研究和仿真分析,特别是通过气动测量主测喷嘴参数的优化设计,使气动测量装置具有相适应的测量范围和灵敏度,从而具有较大的实用性,并最终应用于高档数控珩磨机床的研究。传统气动量仪的参数设计主要采用经验估计,实验比对的方法。通过对空气动力学和流体力学的理论研究,和对气动测量系统的误差分析和传递函数的研究,建立气动量仪参数设计的理论模型。并通过计算机模拟仿真进一步优化气动量仪的设计参数,在理论上对气动测量系统的设计给出指导,然后通过实验验证,使气动测量能更好地应用于机械及各行业。在课题研究阶段,主要通过理论研究与仿真实验相结合的方法,通过对珩磨气动测量和气体动力学的研究,分析研究了差压式气动测量系统的特性,建立珩磨气动测量系统数学模型,研究差压式气动量仪在不同的工作状态,气体的流动状态(临界状态、亚临界状态)变化规律,及对应的压力—间隙函数关系,为研究珩磨气动测量和实验条件下的测量精度提供了有力的理论依据;分析了测量系统气阻、气容和气感与测量精度之间的关系,为旋转密封装置内腔设计,气路管道长度、内径设计提供依据;并研究了护板外圆与被加工孔壁之间的间隙以及喷嘴下沉量与护板包络圆直径对气动测量稳定性的影响,确定针对一定尺寸的孔进行磨头设计时,护板外圆直径、喷嘴下沉量等参数的设计原则。此外,利用流体仿真软件FLUENT对理论结果进行了验证,优化了差压式气动测量系统主、测量喷嘴的结构、尺寸参数并分析了气体流场形式、测量范围、测量精度之间的关系,提出测量元件设计原则;研究了测量压力与测量精度之间的关系,尝试建立不同压力下p s曲线族,并分析压力对曲线线性段位置的影响,提出根据珩磨加工余量和工件尺寸确定测量系统最佳压力的基本原则。
【Abstract】 This topic comes from “high-end CNC machine tools and basic manufacturingequipment” major projects of science and technology, mainly high-end CNC honingmachine, the wheel head component of pneumatic measuring measurement systemoptimization design, through the static experiment and simulation of pneumaticmeasurement system, through pneumatic measurement parameter optimization designof the main measuring nozzle, make pneumatic measuring device adapted to themeasurement range and sensitivity, which have greater practicality, and ultimatelyused in high-end CNC honing machine.The traditional pneumatic measuring the parameters of design, using the methodof experience in estimation and experimental comparison. Theoretical research onthe aerodynamics and hydrodynamics, and pneumatic measurement system erroranalysis and study of the transfer function, to establish a theoretical model of thedesign of pneumatic measuring parameters. And by computer simulation to furtheroptimize the design parameters of the pneumatic measuring instrument, in theory,the design of pneumatic measurement system gives guidance, and then verified byexperiment, make pneumatic measurement can be better used in machinery and otherindustries.In the research stage, mainly the method of combining theoretical studies andsimulation experiments, through research of honing pneumatic measurement and gasdynamics, analysis of the characteristics of the differential pressure pneumaticmeasurement system to establish mathematical model honing pneumatic measurementsystem, research differential pressure pneumatic measuring in the different workingconditions, the gas flow state (critical state, sub critical state) variation, and thecorresponding pressure-the gap function relationship, for study honing pneumaticmeasurement and the measurement accuracy of the experimental conditions providestrong theoretical basis; the relationship between air resistance, the gas content andgas sense and measurement accuracy of the measuring system, design for cavity ofrotary seals, pneumatic pipe length, diameter; study the clearance of between thecircle and to be machined hole wall and nozzle subsidence guard the stability ofpneumatic measurement to determine the grinding head design for a certain size hole,the outer diameter of the shield, nozzle She parameters such as design principles.In addition, use the FLUENT of flow simulation software validation theoretical results and to optimize the differential pressure pneumatic measuring system thestructure of the main measurement nozzle, the size parameters, and analysis of the gasflow field in the form of the relationship between the measurement range and themeasurement accuracy, measuring element design principles is proposed; research therelationship between the measurement of pressure and measurement accuracy, try toestablish a family of curves under different pressures, and analyze the impact ofpressure on the location of the curve was linear segment, the basic principles of thebest pressure of measurement system what honing allowance and the size of the workpiece is proposed to determine.
【Key words】 Honing pneumatic measurement; Differential pressure gas path; Analysisof the flow field; Characteristic curve; Parameter optimization;