活塞环非圆轮廓数控仿形系统

介绍一种活塞环非圆轮廓曲线数控仿形技术及系统外界扰动信号的智能决策与模糊控制技术，以一个近似于二次谐波曲线的凸轮作为驱动刀具进给的正弦机构，进给行程通过调整杆杆杜来改变，可以在电机不反转的前提下，实现刀具进给运动，从而大大提高系统的频响，借助调节电机转度，使刀具进行速度与主轴速度保持某种预定关系（与活塞环型号，规格有关）便可加工出不同型号和规格的活塞环零件，采用智能决策方法和模糊控制规则，形成专家     

矩形滤片骨架的仿形加工

太原读者李力来信,希望本刊介绍有关骨架加工经验。化纤机械制造行业的矩形滤片骨架（如图１所示）端面处尖边ｒ及其尖边处倒圆和抛光,原工艺由手工完成。随着生产批量增加,生产能力已不能满足生产周期要求,产品质量也难以保证。笔者改进了原骨架加工工艺为仿形车削,成功地解决了这一难题。一、工艺技术要求与车床夹具方案的确定１．用车床夹具加工矩形滤片骨架１）改骨架手工锉修端面处ｒ为机械加工,而四角Ｒ１不加工。２）以骨架四直边端面为圆锥形母线,尖边处ｒ在曲线全长上曲率不变。３）达到较高生产率和产品质量。２．矩形滤片…     

仿形修整器仿形样板的设计计算

成形磨削中,砂轮仿形修整精度直接影响零件磨削精度。文章介绍了考虑仿形考虑仿形指尖圆弧半径和金刚笔尖圆弧半径的仿形样板设计计算方法,并用生产实例验证了设计结果。     

压制矩形壳体零件侧表面内凹筋仿形机构设计

为增强矩形壳体零件的刚性和美观度,常常需要在壁部的某些位置成形一定形状和深度的筋。介绍一种仿形机构通过仿形增量成形实现矩形件侧壁内凹筋。实践表明,该仿形机构操作方便安全,同时与之配套的模具简单,获得的矩形件壁部四周的环形压筋连续光顺,质量好。     

大直径活塞环数控立式车床的研究及应用

数字化的发展,对机械加工堪称一次革命。工业领域,对机械加工中获得零件加工精度的要求也逐渐增强。非圆零件加工精度要求越来越高,国内传统加工工艺已难满足要求,数字仿形技术孕育而生。本文将介绍一派直驱开发的一种应用直线电机仿形控制的ECK15125A大直径活塞环数控立式车床。     

瑞士dimaco CTB--170立式内外圆仿形机床改造

1引言CTB--170立式活塞环内外圆仿形车铣床,是瑞士dimaco公司于上世纪80、90年代研发的,专用于活塞环生产加工的设备,问世后经过几代改良。该设备集活塞环内外圆同时仿形加工、开口于一体化的机加工机床。克服了过去车内圆、车外圆、开口三道     

双压轮仿形旋压全自动机床的研制

针对凸台管件的特点,采用双压轮(粗、精压轮)对工件进行仿形旋压加工.开发与利用了滑阀随动装置、靠模板跟踪装置来保证其仿形精度.实践证明,该机床技术先进,质量可靠,值得推广应用.     

“穷人的劳斯莱斯”：FAGOR 8055M／B数字化仿形技术的应用

近年来 ,模具行业日益发展壮大 ,迫切需要一种简化设计和制造过程 ,提高生产效率 ,缩短生产周期 ,保证产品质量 ,价格适中的数控仿形系统 ,专业扫描和数字化测量技术。我厂经过反复调研和试验 ,选择了 FAGOR80 5 5 M/ B数控系统加仿形组件 ,及其伺服驱动和伺服电动机 ,配置雷尼绍 SP2测头组成一套完整的数字化仿形解决方案 ,并已模块化地应用于各类数控机床和加工中心 ,其中以 TH5 6 6 0 A/ F型数控仿形加工中心最为典型。该机在 CIMT’99北京国际机床博览会上首次推出之后 ,便以其优越的性能及令人心动的价格得到广大用户的青睐。这…     

椭圆齿轮的插补法加工

非圆齿轮是各种凸轮上带有轮齿的齿轮，形状各异，有椭圆形、三角形、方形等。非圆齿轮中最常用且加工难度最大的是椭圆齿轮。传统上针对椭圆齿轮加工可采用的方法为仿形法和范成法：仿形法加工时采用成形铣刀，在铣床或铣齿机上进行。但由于椭圆上不同点的曲率半径不同，采用仿形法加工将造成齿顶、齿根宽不同，即齿形不     

车削活塞环工装的改进

通过对活塞环车削工装的改进,提高了生产效率,减少了废品和生产成本。     

Scuffing failure analysis and experimental simulation of piston ring–cylinder liner

The scuffing failure phenomenon of piston ring–cylinder liner is studied theoretically and experimentally. The load and bulk temperature when scuffing failure occurs are measured under different engine speed, lubricant, and environmental temperature in a bench test. Based on the experimental results, the asperity capacity when scuffing occurs is evaluated. Surface contact temperature is determined with the measured bulk temperature and the surface flash temperature calculated by Blok theory. The scuffing failure threshold of piston ring–cylinder liner is established by using specific oil film thickness. This revised version was published online in June 2006 with corrections to the Cover Date.     

Influence of load on the tribological conditions in piston ring and cylinder liner contacts in a medium-speed diesel engine

The present work is an attempt to determine the oil film thickness in a medium-speed four-stroke diesel engine with a cylinder diameter of 200 mm. Experimental research on this topic was found necessary due to the limited amount of published information available with reference to engines of the present size. The experimental part of the study was carried out as firing engine tests, with an instrumented piston, equipped with telemetric data transmission, and an instrumented cylinder liner in a 6-in-line test engine. The study was carried out for different parts of the four-stroke working cycle and for different levels of engine power output. The results were compared with the results of computer simulations, carried out using a commercial software package. The conclusions of the study comprise aspects on the formation and development of the oil film between the rings and the liner under a set of load levels together with the periodical fluctuation during different strokes of the working cycle.     

活塞环数控车床控制系统的研究

对扬州大学机电研究所开发的活塞环数控车床进行数控系统研究。该系统是由工业PC和多轴运动控制器构成两级控制,上位机负责系统界面管理等非实时性作业,下位机负责运动控制、PLC逻辑控制等实时控制任务。通过基于时基的电子靠模实现主轴旋转和径向进给直线伺服电动机的协调控制,完成各种活塞环型线的加工,具有较好的高频响应特性,满足活塞环车削对数控系统的功能要求。     

无润滑压缩机活塞环与支承环过快磨损原因分析

针对无润滑压缩机活塞环、支承环过快磨损进行了理论分析和说明，若安装及使用中重视。可延长活塞环和支承环使用寿命，降低日常维修费用，保障压缩机长周期安稳运行。     

Analysis of the piston ring lubrication with a new boundary condition

Research on the inlet and outlet lubricational characteristics of the piston ring have been intense and ongoing. Many researchers had considered that the entire surface of the ring was enveloped in an oil film, but much experimental research has discovered that not all the entire surface was soaked. To consider a partially lubricated ring, the following conditions are presupposed; oil starvation is applied to the inlet region and the open-end assumption to the outlet region. This algorithm confirms flow continuity and permits the nadir of the pressure to go down to the saturation pressure. Using these new boundary conditions, the actual effective width participating in ring lubrication is determined and the minimum film thickness and flow rate for the ring pack can be calculated. The effective width is expected to be about 20 to 30 percent of the whole width of the ring, and the minimum film thickness is less than the result obtained by using the Reynolds cavitation boundary condition.     

压缩机的活塞制造工艺优化

针对压缩机活塞使用过程中出现的问题，从活塞制造加工方面探讨了工艺优化的措施，在实际使用中延长了活塞的使用寿命，取得良好效果。     

On the effective length of the top piston ring involved in hydrodynamic lubrication

This paper describes a simple analytical model for top piston ring lubrication. The model is constructed using the open‐end boundary condition hypothesis, with an assumption of minimum hydrodynamic pressure in the effective ring length equal to the saturation pressure. The analysis confirms that not all of the ring length is involved in the case of hydrodynamic lubrication, and the effective length is found to be less than 40–50% under some operating conditions. The results are in agreement with previous investigations.     

汽车水箱扩口机自动控制系统的实现过程

结合三菱FX2N可编程控制器（PLC）的特点和汽车水箱扩口机的工艺要求。设计了汽车扩口机自动控制系统软件。用可编程控制器的软件编程取代以前的继电器控制。提高了汽车水箱扩口机的产品质量、工作效率和安全可靠性。     

On the hydrodynamic lubrication analysis of piston rings

A theoretical hydrodynamic lubrication analysis of piston rings is presented. A numerical scheme is developed to solve the Reynolds' equation and the load equilibrium equation simultaneously. The hydrodynamic effects are examined in detail by considering solutions to the problem of lubricating the top compression ring in a two-stroke diesel engine. The minimum film thickness is computed throughout a complete cycle. The pressure profiles and film shapes at different crankshaft angles are presented. In the method proposed, the camtation boundary condition within the lubricated conjunction is included in the analysis.