开关本体加工自动线的研制

文章介绍了燃气灶开关本体自动线的结构和工艺方案及自动线的结构特点,对随行夹具与机床夹具之间的四锥销定位结构及装配工艺做了详细的分析.该小型自动线的研制改变了以往由组合机床通用部件(动力部件)组成自动线的设计方法,拓宽了组合机床自动线的设计思路.     

苏修在组合机床自动线中广泛使用典型中间贮料库

苏修在组合机床自动线系统中,为了用部分补偿相邻自动线的空停时间来提高其生产率,特采用中间贮料库,以便当一条自动线停车时另一条自动线可以继续工作。贮料库的结构取决于贮料库所需容量、工件轮廓尺寸、重量、形状及自动线系统的平面布置。贮料库分为通过式和返回式两种。在通过式贮料库中,在自动线系统工作正常和其中一条自动线停车的情况下,工件通过贮料库。     

MODEL—Y后桥焊接总成加工自动线的研制

介绍了一条用于加工轿车后桥焊接总成的自动线,在深入分析工件结构的基础上,讨论了自动线的加工工艺．结构方案和主要部件结构,分析了自动线的结构特点,用户使用表明了自动线结构设计及工艺方案的合理性。     

CS—UX02转向节加工自动线制造中的工艺问题

文章从满足自动线的检验、调整要求出发,讨论了该自动线随行夹具及样件制造工艺及保证精度的措施。图4幅。馆藏号:     

配有桁架机械手、可换箱机床的缸体柔性加工自动线的开发研制

讨论了一条由加工中心、可换箱机床、斜孔钻机床组成的缸体自动线的设计方案,并对整条自动线的布局、结构、工作原理、输送形式及数控系统等做了较为详细的介绍.该自动线的成功研制和应用,结束了国内用户依赖进口该类产品的现状.     

组合机床专题讲座(九) 电气控制系统的设计(八)

五、自动线电气原理图设计 自动线电气控制的功能通过电气原理图表现出来。自动线电气控制系统的设计,主要就是设计电气原理图。电气原理图虽然是表示全部控制功能的总体,但它是可以按各个特殊控制功能分类的。前面介绍了自动线的一般控制原理及实现控制目的的不同方法,然后又介绍了各个控制环节。在这一部分中,将讨论如何应用上述知识,根据自动线的要求设计电气原理图。即使是一条比较简单的自动线,其电气原理图的篇幅也是比较大的。如果在这一部分     

国外组合机床生产技术发展现状(五)

六十年代后期,国外组合机床自动线在产量上发展得比较快。在美国,每年生产的组合机床中大约有80～90％为多工位机床及自动线,在西德有50～60％为自动线,在日本约40～50％为自动线。而西德、日本等国的厂家,在六十年代初,自动线产量不过占20％左右。随着产量的增长,在技术水平上也有了较大的发展,但主要还是六十年代初期及中期出现的一些新技术的普及和应用。这方面主要是;缩短节拍时间,扩大工艺范围,提高加工精度,提高自动化程度,简化机械系统机构以及电子技术及部分气压技术的应用。自动线的组成,实质上是机械、电气、液压、气压四种技术的结合,是一种电气和气压控制的自动化机械。从自动线的结构来看,最近几年的发展主要表现在如下几方面:     

机械加工自动线的若干问题探讨

本文从历史的观点指出,自动化技术象历史上其他技术进展一样,促进了社会生产力的发展,并提供了更多的工作机会。把丰富的廉价劳动力与采用自动化技术对立起来的观点是不可取的。对我国自动线存在的问题进行分析的基础上着重指出组织管理方面的因素对建线质量的影响。自动线设计方面也相应存在着不足。本文试图以生产纲领的确定,投资指标、回收期的确定及计算等作为建线的依据,以防止自动线建线的盲目性及经济效果评价的虚假性。文中提出自动线的回收期应按产品寿命,建线的平均周期及自动线复杂程度浮动。在年节约额的计算中,除包括建线前后的成本差额外,还应包括生产能力不平衡引起的自动线开工不足造成的附加费用及“短线零件”建线所带来的附加收益。应力求对自动线经济性的考核更加切合实际。     

神龙公司缸盖4条加工自动线简介

文章介绍了神龙公司的加工缸盖顶底面、两侧面、两端面、气门导管、阀座和火花塞孔的4条加工自动线的工艺内容、精度要求、自动线的布局及结构特点.     

提高自动线生产率指标的可能性

文章对用于计算和评价自动线及自动线系统生产率的指标进行了探讨,列出了这些指标的数值范围。根据已进行过的研究,提出了能提高自动线及其系统生产率的一系列措施。     

Morphology and electrical contact properties of electrical connection materials in corrosive atmosphere

The impact mechanism of environmental factors, such as corrosive atmosphere, on connector materials was investigated, and the porosity of gold plating was tested. Series of inspections and analytical research methods were introduced in this article. The surface morphology of specimens after corrosion was observed by stereoscopic microscope and scanning electron microscope. Chemical constitution was examined by X-ray energy spectrum. The contact resistances were measured by four-point method. The experiment results show that after exposure to certain environment, the corrosion products, such as Cu2O, Cu(NO3)2·3H2O, and NiO, are observed on the surface of the specimens without gold coatings, whereas the corrosion products appear to have circle-shaped spots on gold-plating surface after corrosion test, which indicate that the gold plating has good corrosion protection. The porosity is increased with the increase of corrosion time for every kind of specimens gold plated, and the corrosion degree of goldplating specimens is decreased with the increase of the thickness of gold coatings. The static contact resistances of circle-shaped spots appear higher contact resistance than normal value, which can reach to 2,000 mX nearly. It is found that the high and unstable contact resistance of the pore and products is more likely to cause contact failure.     

掺杂对WCu电触头材料电弧特性的影响

利用粉末冶金技术制备出分别掺杂0.3%B、2.0%Nb和1.5%Ce (质量分数)的WCu电触头材料,采用高速摄影技术和抗电弧烧蚀实验探讨不同掺杂元素对钨铜电触头材料电弧特性的影响.结果表明:真空击穿时,WCu电触头材料的电弧演化过程可以分为起弧、稳定燃烧和灭弧3个阶段;掺杂0.3%B、2.0%Nb和1.5%Ce的WCu电触头材料的电弧寿命比未掺杂的长,截流值小;等离子云体积大,颜色浅,在样品表面燃烧区域大,电弧分散,燃弧能量分散;电弧燃烧稳定,无放射状光芒.含有掺杂元素的WCu电触头材料的抗电弧烧蚀性能均得到明显改善;其中最明显的为WCu-B电触头材料,其抗烧蚀性能提高了近30%.     

CNC电动螺旋压力机

电动螺旋压力机具有能量可控,锻件精度高等优点,广泛应用于各种材料的精密锻造.本文提出了一种采用电机经齿轮传动带动螺杆直接驱动的机械结构方案,改变电机的转速和输出力矩,将电能转化为飞轮储能.这种直接驱动方法为打击能量计算机精确控制提供了可能.通过矢量控制和直接转矩控制两种电机驱动控制方式实现打击能量控制,减少启动冲击电流.给出了由PLC和变频器组成的控制系统的硬软件实现方法.配置了由单片机组成的打击力显示器.所研究的成果已用于实际生产中.     

Near dry electrical discharge machining

This study investigates the near dry electrical discharge machining (EDM) process. Near dry EDM uses liquid–gas mixture as the two phase dielectric fluid and has the benefit to tailor the concentration of liquid and properties of dielectric medium to meet desired performance targets. A dispenser for minimum quantity lubrication (MQL) is utilized to supply a minute amount of liquid droplets at a controlled rate to the gap between the workpiece and electrode. Wire EDM cutting and EDM drilling are investigated under the wet, dry, and near dry conditions. The mixture of water and air is the dielectric fluid used for near dry EDM in this study. Near dry EDM shows advantages over the dry EDM in higher material removal rate (MRR), sharper cutting edge, and less debris deposition. Compared to wet EDM, near dry EDM has higher material removal rate at low discharge energy and generates a smaller gap distance. However, near dry EDM places a higher thermal load on the electrode, which leads to wire breakage in wire EDM and increases electrode wear in EDM drilling. A mathematical model, assuming that the gap distance consists of the discharge distance and material removal depth, was developed to quantitatively correlate the water–air mixture's dielectric strength and viscosity to the gap distance.     

High-speed dry electrical discharge machining

A novel high-speed dry electrical discharge machining (EDM) method was proposed in this study. Using this method, the material can be rapidly melted by extremely high discharge energy and flushed out of the discharge gap by high-pressure and high-speed air flow. The material removal rate (MRR) of dry EDM was significantly improved by the proposed method. The MRR of dry EDM is usually in tens mm³/min, whereas the MRR of the proposed method can be as high as 5162 mm³/min, which improves the MRR by 2nd to 3rd order of magnitude. Investigation was conducted systemically. The influences of work piece polarity, discharge current, pulse duration time, gas pressure, and electrode rotation speed on machining performance were studied. The machining mechanism of this method was thoroughly analyzed. Moreover, the re-solidified layer, surface morphology, elementary composition, and phase of AISI 304 stainless steel for high-speed dry EDM were also investigated. Theoretical and technical foundations were laid for the industry application of dry EDM.     

High-voltage influence of an electrical discharge on the durability of an electrical rod conductor

Dissipation of energy regimes with the electric discharges have been considered, Dissipation of energy effect the deformed-stressed condition of the conducting road, and thus, determines its strenght and resources.     

Ferrocene-cored-conjugated dendrimer with electrical bistability

In this study, we report synthesis of a ferrocene-cored-conjugated dendrimer and its electrical property. The ferrocene-cored-conjugated dendrimer is covalently linked by a redox active ferrocene moiety and π-conjugated dendrons. Photophysical properties showed a remarkable fluorescence quenching of the dendrimers possibly due to electron transfer from the ferrocene moiety to the half-occupied HOMO level of the conjugated dendrons. The I–V–R (current–voltage–resistance) characteristics of the single layer device, ITO/dendrimer/LiF/Al, exhibited clear electrical bistability for organic memory application, i.e. the low-conductivity state (OFF state) and the high-conductivity state (ON state). The result would provide a new class of materials with further opportunities for organic electronics.     

Properties of nitrided electrical steels

Autorepair Scientific and Production Union, Saratov. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 3, pp. 15–17, March, 1989.