直线式箱体全自动无氟发泡线充注机械手的设计

介绍了直线式全自动箱体发泡线充注机械手的结构及其驱动系统,该系统可直接应用在新箱体发泡线的制造上,又可用在老箱体发泡线的改造上,因此具有极大的推广价值和显著的经济效益.     

铜线替代金线在晶体管封装中的压焊工艺研究

通过比较铜线与金线的性能,论述了铜线压焊的特点、设备的改造、铜线产品质量检验与常见不良产品等,在晶体管产量较大时,使用铜线压焊能有效地降低生产成本,因而在通用民品中有着非常广阔的应用前景.     

金亿机械有限公司:玉米收获机创造新纪录

11月18日,山东金亿机械制造有限公司在美丽的海滨城市日照举办了山东省玉米机械化发展与推广研讨会暨2008年商务年会.原计划600多人参加的会议却来了900多人,这在金亿公司是史无前例的,让公司领导及员工忙得不亦乐乎.金亿公司董事长马金英满面春风对记者说:"人气旺盛,一是得益于党的政策好,二是今年金亿公司拥有喜人的表现,小麦机产销1600台,市场占有率由去年的5%提升为15%,玉米机销售1200台,占行业内同类机型首位.同时,金亿产品也是获得政府补贴最多的产品."     

SIMATIC IT助力制造

西门子中国有限公司的业务结构涉及的行业和领域主要包括:信息通讯、自动化与控制、医疗、照明、能源、交通、金融和房地产等.西门子MES属于西门子自动化与驱动集团,这个业务集团是西门子最古老的集团之一,在中国的业务也发展非常好,产品覆盖各行业客户的自动化需求.自动化与驱动集团分为七个部门,MES隶属于其中的自动化与系统部.整个集团全球有近10万种产品,每个月约有18种新产品问世.自动化与驱动集团将其年销售额的约9%用于研发投资,尤其在工业软件方面很多人都认为自动化是一个硬件设备,但随着现在软件的发展,西门子也提供大量的软件开发.     

为推动国内实验室离心机行业升级而努力——专访上海安亭科学仪器厂董事长陆永泉先生

我国的实验室离心机产业近年来在研发生产方面取得了进步,但由于大部分企业的规模较小等原因,整体上与国外产品尚有一定差距。《中国仪器仪表》杂志记者专访了上海安亭科学仪器有限公司董事长陆永泉先生,陆先生评述了实验室离心机行业现状并提出了提高产品水平的措施,为推动国内实验室离心机行业升级提供了很好的建议。     

"数字化组织"迈出智能化敏捷制造第一步

PTC这支在船舶领域雄立多年的老牌劲旅,早在1992年就开始涉足船舶业,并取得了不错的成绩,1998年收购CV公司后更加强了其在船舶业的发展势头.目前在中国,军船市场一直占主导地位,民船虽然近几年才开始兴起,但市场表现也不俗.2007年我国的船舶业迎来了前所未有的井喷时期,也为PTC船舶业绩的提升带来了发展良机,而这一切早已洋溢在了PTC中国船舶业销售总监王慧杰的脸上.     

颅骨解剖机械设备的研制

本文针对目前法医解剖人体颅骨用设备存在的问题,探讨研究一种科学实用的颅骨解剖专用设备,用以提高解剖人员的工作效率,提高解剖质量,改善工作环境.     

防雨、防暴晒、夜晚能自动收缩的智能晾衣架设计

智能晾衣架的机械部分是在普通拉杆式晾衣架两支撑杆的端部各安装一个滑轮,再穿入钢丝绳.钢丝绳与最前外面的晾衣杆固定连接.钢丝绳的另一端连接到与直流电动机相连的转轴上,通过电动机的正反转达到晾衣架的伸缩效果.其控制部分的电路CPU采用89C2051单片机.利用温度、雨水、光敏等传感器,达到下雨时自动收回,雨后自动伸展;气温高于设定值时自动收回,低于设定值时自动伸展;夜晚自动收回,白天自动伸展的功能.     

船舶螺旋桨的偏振和抗冲击稳定性研究

船舶螺旋桨的偏振对螺旋桨叶片的寿命和船体尾部的振动情况有着重要的影响,为了减少螺旋桨偏振、提高其抗冲击稳定性,运用理论分析和实验室模拟测试手段,研究了螺旋桨偏振发生的频段,提出了防范措施,具有广阔的推广应用前景.     

基于WTK冷冻缸产品设计及加工虚拟现实软件的开发

在虚拟环境中利用数字化产品模型来代替实物模型进行仿真、分析,实现产品设计和制造过程的集成,已成为目前产品开发技术的重要发展方向.文中应用SolidWorks实现产品零配件和虚拟车床、夹具的实体造型,在VC 6.0开发平台上采用与World Tool Kit软件相结合的方法,同时利用与实体造型连接的技术实现虚拟设计和运动视景仿真并虚拟加工过程.     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

Book Reviews

Book reviewed in this article: Advanced Scanning Electron Microscopy and X-ray Microanalysis . By Dale E. Newbury , David C. Joy , Patrick Echlin , Charles E. Fiori and Joseph I. Goldstein A Scanning Electron Microscope Atlas of the Honey Bee . By E. H. Erickson , S. D. Carlson and M. B. Garment Electron Microscopy of Proteins , Volume 5. Viral Structure . Edited by James R. Harris and Robert W. Horne Filtres Optiques . by M. Françon Optique Géometrique, Matricielle et Ondulatoire . By J. Ph . Pérez     

EXPERIMENTAL RESEARCH AND DESIGN ON HEAT TRANSFER OF EVAPORATOR USED IN THE LARGE QUICK FREEZE PLANT

The evaporator is the main part of a quick-freeze equipment. There are many factors influencing the heat transfer coefficient of an evaporator. The most important factors among them are the fin shape, tube diameter, distance of fin space, frost, and velocity of air flow etc. They mainly influence the thermal efficiency of an evaporator, and therefore its thermal efficiency has direct relationship with the whole efficiency of the quick freeze plant. Evaporators with different structural types have different heat transfer efficiency. In order to obtain high efficiency structure of evaporator, 8 evaporator models with different fin shape, tube diameter and tube arrangement are analyzed and compared. The calculation results show that the integral waved fins, equilateral-triangle arranged small diameter tubes and varying fin-spacing has the highest heat transfer coefficient. The experimental result also shows that the evaporator with this type of structure has better thermal efficiency. The experimental result is in good agreement with the calculation result. It can instruct engineering design for usual designer. A real quick-freeze equipment is designed and put into production. The result shows that, compared with traditional domestic quick-freeze equipments, this equipment decreases by 40% in size and by 20% in energy consumption.     

Research on the calibration method of precipitation micro- physical characteristics sensor

In order to diminish the effect of the ambient light and CCD pixel non-uniformity to the Precipitation Micro-physical Characteristics Sensor,a modified calibration scheme was designed and calibration experiments in sunny,cloudy,night,different location of sample space were carried out. Firstly,the characteristics of particle images which affected by ambient light and different location of sample space were analyzed. Secondly,the relevance betw een particle image features and parameters of image processing were discussed. Finally,the parameter setting scheme were determined,the radium of median filtering algorithm is 3 pixels,the defocusing radius of point spread function( PSF) is 7 pixels,the radium of erosion is 3 pixels,and the binary threshold is obtained from the Area-thresh relationship. The results show that the new scheme could deal with the image calibration well,the average errors of equivolumetric diameter was 0. 041 mm with standard deviation of 0. 115 mm,and the average errors of the axis ratio was 0. 011 with standard deviation of 0. 085. The new scheme works well in the field observation too,the observed axis ratio is consistent with the empirical relationship that proposed by Beard. The relative error of accumulation precipitation is-3. 06% after calibration,w hich is improved 1. 94% low er than the initial one without calibration.     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Estimation of surface area and length with the orientator

The orientator is a new technique for the estimation of length and surface density and other stereological parameters using isotropic sections. It is an unbiased, design-based approach to the quantitative study of anisotropic structures such as muscle, myocardium, bone and cartilage. A simple method for the practical generation of such isotropic planes in biological specimens is described. No special technical equipment is necessary. Knowledge of an axis of anisotropy can be exploited to optimize the efficiency. To randomize directions in space, points are selected with uniform probability in a square using various combinations of simple random, stratified random, and systematic random sampling. The point patterns thus produced are mapped onto the surface of a hemisphere. The mapped points define directions of sectional planes in space. The mapping algorithm ensures that these planes arc isotropic, hence unbiased estimates of surface and length density can be obtained via the classical stereological formulae. Various implementations of the orientator are outlined: the prototype version, the orientator-gencrated ortrip, two systematic versions, and the smooth version. Orientator sections can be generated without difficulty in large specimens; we investigated human skeletal muscle, myocardium, placenta, and gut tissue. Slight practical modifications extend the applicability of the method to smaller organs like rat hearts. At the ultrastructural level, a correction procedure for the loss of anisotropic mitochondrial membranes due to oblique orientation relative to the electron beam is suggested. Other potential applications of the orientator in anisotropic structures include the estimation of individual particle surface area with isotropic nucleators, the determination of the connectivity of branching networks with isotropic disectors, and generation of isotropic sections for second-order stereology (three-dimensional pattern analysis).     

Research on key techniques of expendable conductivity temperature depth measuring system

This paper analysis the developing of expendable conductivity temperature depth measuring system(XCTD)and introduce its principle of measuring about temperature,salinity and depth of ocean.Some key techniques are put forward.According to the real needs of XCTD,conductivity sensor with high sensitivity is designed by principle of electromagnetic induce,the ocean conductivity from induced electromotive force has been calculated.Adding temperature correction circuit would help to reduce error of conductivity measurement because of sharply changing temperature.Advanced temperature measuring circuit of high precision and the constant current source is used to weaken effect of self-heating of resistance and fluctuation of the source.On respect of remote data transmission,LVDS is a good choice for the purpose of guarantee the quality of data transmitted and the transmission distance is reaching to thousand meters in the seawater.Modular programming method is also brought into this research aimed at improve the stability,reliability and maintainability of the whole measuring system.In February,2015,the trials in South China Sea demonstrate that the developed XCTD realize effective measurement at a speed of 6 knots and detection depth at 800 m.The consistency coefficient of the acquired data is greater than 0.99 and the success rate of probe launching is above 90%.     

Friction-induced ignition modeling of energetic materials

The heat released during the external frictional motion is a factor responsible for initiating energetic materials under all types of mechanical stimuli including impact, drop, or penetration. We model the friction-induced ignition of cyclotrimethylenetrinitramine (RDX), cyclotetramethylene-tetranitramine (HMX), and ammonium-perchlorate/ hydroxylterminated-polybutadiene (AP/HTPB) propellant using the BAM friction apparatus and one-dimensional time to explosion (ODTX) apparatus whose results are used to validate the friction ignition mechanism and the deflagration kinetics of energetic materials, respectively. A procedure to obtain the time-to-ignition for each energetic sample due to friction is outlined. This paper was presented at the 7th JSME-KSME Thermal and Fluids Engineering Conference, Sapporo, Japan, October 2008. Min-cheol Gwak received his B.S. degree in Mechanical Engineering from Korea Aerospace University, Korea, in 2007. Now he is a graduate student of Mechanical and Aerospace Engineering at Seoul National University in Seoul, Korea. His research interests are ignition of high energy material and combustion phenomena. Tae-yong Jung received his B.S. degree in Mechanical and Aerospace Engineering from Seoul National University, Korea, in 2007. Now he is a graduate student of Mechanical and Aerospace Engineering at Seoul National University in Seoul, Korea. His research interests are solid propellant combustion and phase transformation. Professor J. Yoh received his BSME from UC Berkeley in 1992 and MSME from UCLA in 1995. His doctoral degree is in Theoretical & Applied Mechanics from the University of Illinois at Urbana-Champaign, 2001. His research interest is in high energy system design using high power lasers and condensed energetic materials.     

交通荷载作用下桥梁结构参数识别方法

应用动力节点加载法,将作用在桥梁上的交通荷载转化为等效节点荷载,再用两步构造法识别结构物理参数.第1步,用Newmark-β方法变换结构运动方程,并用结构的加速度响应求得变换空间内的位移、速度和加速度响应;第2步,基于最小二乘原理,构造出变换空间内求解结构参数的递推式,进行结构物理参数识别.数值模拟结果表明,在交通荷载作用下,该方法能够快速、准确地进行桥梁结构参数识别.     

The use of chemiluminescence in determining the thermal and oxidative stability of motor oils

Chemiluminescence is reviewed as a method of characterising different behaviour of lubricating oils. This includes mineral oils containing additives such as zinc dialkyl-dithiophosphates, sulphonates, succinamides. alkylphenols and polymers. Using a chemiluminescence apparatus and manometric apparatus, various lubricant oil fractions blended with additives were examined. The basic emitters of chemiluminescence are excited carbonyl compounds, and results are presented showing the measurement of chemiluminescence at elevated temperatures.