磨削方式对单晶硅表面磨削温度的影响

研究金刚石砂轮磨削单晶硅片时的表面磨削温度 .针对平形砂轮和杯形砂轮两种不同平面磨削方式所产生的表面磨削温度特点进行了比较分析 .对砂轮粒度和磨削深度对这两种平面磨削方式的表面磨削温度的影响进行了试验研究 ,得到了一些有意义的试验结果和结论     

钎焊金刚石砂轮磨削大理石的力的变化特征

通过测量和分析高频感应钎焊金刚石砂轮磨削大理石过程中的磨削力，对砂轮所受的法向力和切向力进行了研究。从单颗金刚石最大切削厚度的角度。分析了磨削深度、进给速度和砂轮线速度时磨削力的影响。     

砂轮金刚石混合体制备的工艺分析

针对目前砂轮金刚石混合体中存在的问题，本提出了金刚石混合体制备的方法。本方法制备的金刚石混合体砂轮具有耗量小、性能稳定的特点。     

基于绿色制造的雾中放电修整金刚石砂轮实验研究

在电火花成形机床上进行了雾状去离子水放电修锐青铜结合剂金刚石砂轮实验,研究了放电工艺参数对砂轮微观形貌、修整效率和容屑空间的影响。结果表明：峰值电流和脉冲宽度是影响金刚石砂轮修整表面形貌和修整效率的主要因素;调整放电峰值电流和脉冲宽度可以获得较好的修锐效果,并能有效提高砂轮的磨削能力。     

金刚石磨具表面磨粒的三维分布模拟

研究了粒径为125~150μm的金刚石磨粒在砂轮表面的分布情况,并对金刚石磨具表面磨粒的三维分布进行仿真分析,仿真结果表明脱落是固结金刚石磨具磨粒失效的重要形式;金刚石分布具有一定的聚集性;仿真分布具有一定的干涉。     

特殊工件磨削加工的数学建模

特殊工件精密磨削是一个复杂的多变量影响过程,本文开展了精密磨削加工技术的优化研究。在利用已知加工外表面母线方程的基础上,采用了精密数控曲线磨削砂轮法向跟踪的方法,通过保证曲线轮廓上磨削点处的法线经过砂轮的回转平面,实现了砂轮与工件之间的恒定点接触,在分析砂轮与工件运动几何关系的基础上,建立了砂轮法向跟踪的数学模型,从而提高了加工精度,实现了对任意复杂曲线轮廓的磨削加工。     

磨削加工工程陶瓷磨削用量的可视化研究

在陶瓷材料的磨削加工过程中 ,金刚石砂轮特性和磨削用量直接影响磨削表现质量。文章把明确表征金刚石砂轮特性的主要指标参数进行综合 ,在一定假设条件下建立了砂轮特性参数和磨削用量间的函数关系 ,进一步利用MAT LAB分析软件 ,对这些参数和磨削用量之间的相互关系和相互影响进行了可视化研究 ,从某些方面解决了磨削加工过程中砂轮特性参数和磨削用量的选择问题。特别是在选定某一磨削用量数值后 ,如何确定其余磨削用量的选择范围问题。     

树脂结合剂金刚石砂轮磨削火成岩质水晶的磨削力研究

采用270目树脂结合剂金刚石砂轮以顺磨磨削方式对火成岩质水晶进行平面磨削实验。通过测量磨削过程中的磨削垂直力和水平力,得出砂轮线速度、进给速度、磨削深度对磨削力的影响特征。实验结果表明,当提高砂轮线速度时磨削力减小,增大进给速度时磨削力增大,增大磨削深度时磨削力增大。最后对火成岩质水晶磨削力比进行讨论和分析,拟合出磨削力比Ft/Fn为0.085。     

叶轮增压式内喷润滑砂轮基体结构设计

提出了一种冷却介质通过内部进入磨削弧区的叶轮结构内喷润滑砂轮;分析了叶轮增压式内喷润滑结构及润滑原理;设计了叶轮式增压内啧润滑砂轮基体结构,对叶轮叶片出口角、出入口直径、叶片数和叶片形状等参数进行了计算,得到了优化的叶轮式砂轮基体结构设计参数.     

磨削加工中砂轮堵塞影响因素的试验分析

砂轮堵塞是影响砂轮耐用度的主要原因，本文通过正交设计试验方法，研究了在纵向磨削时，工件转速、修整速度、冷却方式、磨削厚度等因素对砂轮堵塞的影响。     

Electro-Discharge Fine Truing of Metal-Bonded Fine-Grain Diamond Wheel Based on Real-Time Monitoring

A data acquisition system based on LabVlEW is designed and implemented, and electrodischarge(ED) fine truing of metal-bonded fine-grain diamond wheel based on real-time monitoring is researched. Real-time monitoring not only makes efficient impulse specification of ED truing easily obtained, but also is good for timely identifying no-load, avoiding short circuit and arc discharge phenomena and then for obtaining normal machining state. ED fine truing of the fine-grain wheel includes two steps: rough truing for high efficiency and fine truing for high precision. Final ED truing precision and efficiency not only depend on electric process specification, but also is concerned with electrode shape, insulated performance of operating fluid and vertical feed quantity value and frequency. Experiments indicate that ED fine truing based on real-time monitoring can improve the truing precision and efficiency. Average machining efficiency of W10 wheel is about 0.95μm/min； the final run-out by ED truing is less than 2μm.     

Anode Simulation and Cathode Design for Electrolytic Dressing of Diamond Profile Wheel

The design methods of anode and cathode are proposed for precision profile grinding.Based on the electrolytic machining theory, electrolytic equilibrium condition and Faraday‘s law of electrolysis are applied to establishing the mathematical model of profile diamond dressing processes. A finite element method (FEM) program is developed to solve the inverse boundary problem of Laplace‘s equation. Desired anode contour or cathode shape is determined by computing the distribution of electric potential layer by layer. Electrolytic machining experiment is carried out to verify the simulated anode shape. The research result shows that shape deviation between designed cathode and profile wheel increases with the value of angle between feed rate and the normal to anode surface. The shape of simulated anode is consistent with the contour of metal-bonded diamond profile wheel for a given cathode. Based on the anode contour, cathode shape can also be designed accurately.     

A Web-based on-machine mould matching and measurement system based on CAD/CAM/CAI integration

INTRODUCTION Today, the manufacturing industry makes con- stant effort in order to construct an E-manufacturing system using information technology for effective production control, and then, it offers the integrated production control to the workers, the production managers, and the consumers, etc. (Lee, 2003; Choi, 2004). In the mould manufacturing industry, the process managers often request paperwork to know the information of the processes on CNC machine tools or they visit the shop…     

电动自行车后轮碟刹安装设计

随着电动自行车设计的最高车速的提高,对刹车系统提出更高的要求,为此提出电动车实现后轮碟刹的设想。经对后轮碟刹实现的可能性及后轮碟刹装置安装方法的分析,结果：后轮具有安装碟刹装置的空间。并可以通过改造链条齿轮或电机壳的方法来实现后轮碟刹装置的安装。     

Attitude stabilization of a pico-satellite by momentum wheel and magnetic coils

The three-axis active attitude control method with a momentum wheel and magnetic coils for a pico-satellite is considered. The designed satellite is a 2.5 kg class satellite stabilized to nadir pointing. The momentum wheel performs a pitch-axis momentum bias, nominally spinning at a particular rate. Three magnetic coils are mounted perpendicularly along the body axis for precise attitude control through the switch control mechanism. Momentum wheel start up control, damping control and attitude acquisition control are considered. Simulation results show that the proposed combined control laws for the pico-satellite is reliable and has an appropriate accuracy under different separation conditions. The proposed strategy to start up the wheel after separation from the launch vehicle shows that its pitch momentum wheel can start up successfully to its nominal speed from rest, and the attitude convergence can be completed within several orbits, depending on separation conditions.     

铁路钳夹式车辆止轮器的开发与应用

传统的止轮铁鞋或者是木楔式止轮器都是自然放在钢轨上与车轮贴合,靠车辆重力压紧来实现止轮,这两种止轮工具与钢轨之间不固定,在使用过程中可能会因为外力原因产生滑动,导致止轮工具与车轮踏面之间出现不密贴的现象,这种情况下止轮是失效的,而钳夹式止轮器是固定在钢轨之上,一般的外力作用不会使止轮器产生滑动,所以避免传统的止轮铁鞋或木楔式止轮器与车轮踏面之间出现不密贴的现象,实现安全止轮。     

Design optimization on the front wheel orientation parameters of a vehicle

1. Introduction In order to improve the driving operation performance, the front suspension of a vehicle is generally of McPherson independent style, which can simplify the structure, lighten the unsprung mass, and conveniently arrange the engine and steering system. Moreover, it can adapt to many types of springs and is of advantage to adjust the height of the vehicle. In such a system, the axis of the kingpin is the line between the upper damper end and the intersection of the transverse ar…