关于振兴东北科学仪器基地问题"振兴东北科学仪器高层专家研讨会"上的发言

科学仪器不仅是科学研究、经济和社会发展离不开的重要的工具，它本身也是一种高技术产品。科学仪器的水平直接反映了一个国家的科学技术和经济发展的水平，因此很多国家，特别是发达国家，都将科学仪器作为一种支柱产业大力加强发展。在美国科学仪器直接影响到它的三分之二的GDP，美国商务部也真正在着力的研究，如何进一步的推动它大量的中小型科学仪器企业的发展和加强它的出口。     

山高人为峰——访“霸王”集团总裁刘令祥

对时钟行业略有知晓的人,肯定知道"霸王"的刘总,知道刘总的人想必都很想会会刘总.在时钟的圈子里,刘总是个很有意思的人,说他有意思是因为在旁人来看,他是个倔强的老头,为人低调.在国内展会上,你基本看不见"霸王"的展位,而在瑞士的巴塞尔展上你会找到;在中国的很多地方都有"霸王"的工厂;他很少参加钟表会议,而他们的产品屡屡是销量冠军;很多人在模仿"霸王"产品,而刘总说别人永远模仿不来;在竞相压价的时钟市场,"霸王"的价位总是居高不降;在其他人看来,"霸王"的时钟已经做的很大很好,刘总却说时钟只是"霸王"产业的一小部分.     

信息化的"追星族"——上药集团抗生素事业部采供中心总经理任学军

谈到信息化的实施,任学军的开场白是,信息化的推行势在必行,企业面临的已经不单单是管理方面的问题了,尤其是上规模的企业,品种种类繁多,办公地点分散,如果没有信息系统的准确和及时性作支撑,企业将无法实现管理.不像是一个车间,一个领导上下走一圈就可以管理的时代了.可见,ERP是在一片呼声中开始实施的.     

奥运来时看分秒

2008年8月8日,中国人将迎来百年期待的奥运会,届时,中国体育健儿将于各国、各地区的运动员共同见证"更高、更快、更强"的奥林匹克精神,创造更多辉煌时刻.作为"更快"表现的速度需要时间来度量,而计时器便担当起了度量的任务,比如说大家期待刘翔能在家门口打破他创下的奥运记录,但这个成绩相差就在0.01秒之间.在奥运场上,计时无处不在,争分夺秒是运动员拼搏精神的体现,时间的分秒毫厘则是钟表师的聪明智慧所在.     

液压-气压传动技术在电动车减振系统中的应用

介绍了电动车减振技术的现状以及所存在的不足.通过对电动车液.气压减振器的设计、前(后)轮的结构设计、车胎的规格选择、刹车制动方式的选择等4个方面的分析,指出了液压.气压传动技术在整车减振技术发展中的趋势.     

提高会计服务质量的关键是加强职业判断力

通过对现阶段会计职业判断力的分析,指出从事会计的工作人员必须提高对会计职业判断力的认识,并结合实际情况制定了提高会计职业判断力的具体措施,提升会计职业判断力的水平.     

谋定而后动打造"智能化"现代造船企业——访天津新港船厂总工程师梁有祥

当记者走进新港船厂大门的时候,产生了一种熟悉的感觉--典型的老国营企业的建筑、工人和厂房.尽管下着细雨,但是机器的隆隆声和形色匆匆的工人提示着这仍是上班时间.这样的老厂,2001年甚至面临破产的境地,其信息化建设会是怎样一个艰难的状况呢?操着一口浓郁的天津话的总工程师梁有祥接待了记者.     

瑞士华嘉(香港)有限公司及独家代理欧美部分分析仪器介绍

瑞士华嘉公司是一家著名的国际贸易集团，总部位于瑞士的苏黎世。华嘉公司自1900年以来便与中国进行友好贸易往来，业务范围涉及机器、仪器、消费品、食品原料、化工原料等诸多领域。“科技的市场智慧”是对华嘉公司形象的准确概括。高品质的产品，专业的应用及完善的售后服务，对各种客户文化背景的深该理解以及娴熟的市场贸易技巧使得客户获得的不仅是经济上的利益，而且是技术上的进步。     

基于PLC控制的搬运机械手的应用

论述了搬运机械手的功能、结构原理及软件设计.结合大蒜根须切除设备中大蒜的搬运,详细介绍了PLC的选择、I/O的分配、PLC与器件的逻辑电路连接及系统的气动原理.     

全自动伺服多功能芯体组装机的研制

文章从技术角度对汽车铝换热器的冷凝器、暖风、水箱的芯体组装进行了深刻的探讨,将国际领先的一机多能技术应用到汽车换热器的芯体组装上,提高了产品的适应性,增加了使用寿命,更重要的是解决了实现多品种芯体组装的难题.     

IDEF0 Model of the Measurement Planning for a Workpiece Machined by a Machining Centre

A comprehensive analysis of the entire measuring operation for a workpiece machined by a machining centre should be conducted systematically before the application of a planning technique. For this purpose, an IDEF0 model is used in this paper to plan the measuring sequence and operation of a coordinate measuring system for a workpiece machined by a machining centre. Generally speaking, a machining centre can machine workpieces having complicated shapes. Therefore, the planning of measurement procedures and operations on a workpiece machined by a machine centre requires consideration of issues such as the position and measuring sequence of the measurement points, how to avoid probe collision during measuring, which fixture elements are required for measuring fixtures, and where the support points of fixtures and position of fixture locations should be.     

高速铣削淬硬模具钢的工艺性与经济性研究

高速加工机床及其刀具技术的最新发展使得在模具和零件制造领域实现“以切代磨”成为可能 ,用超硬刀具高速切削淬硬模具钢等难加工材料已得到越来越广泛的应用。由于模具或零件的高速切削加工可免除磨削或抛光等后续工序 ,因此精加工时如何保证工件最终表面质量同时将加工成本控制在可接受范围之内是研究人员关注的重要问题。本文在调查的基础上分析了用于高速铣削淬硬模具钢的整体硬质合金涂层立铣刀的切削性能和经济性 ,并给出了部分应用实例     

An effective-wire-radius compensation scheme for enhancing the precision of wire-cut electrical discharge machines

Using a modified Denavit–Hartenberg (D–H notation), we propose with this study a methodology for generating the wire-radius-compensated NC data equations required to carry out the machining of non-column workpieces on a five-axis wire-cut electrical discharge machine (WEDM). In the proposed approach, the designed surfaces of the machined component are constructed using a 4?×?4 homogeneous transformation matrix and ruled surfaces. The modified D–H notation is then employed to derive the machine’s ability matrix and to generate the desired wire location matrices. To ensure the precision of the machining operation, the wire location matrices are modulated by a novel effective-wire-radius compensation scheme. Finally, the NC data equations required to machine the component are derived by equating the ability matrix with the modulated wire location matrix. To validate the proposed methodology, three non-column workpieces with various top and bottom basic curves are machined on a commercial WEDM. The dimensions of the machined components are then compared with those of specimens machined using the built-in WEDM compensation scheme. The results show that the components manufactured using the proposed effective-wire-radius compensation scheme are more geometrically precise than those produced using the conventional WEDM compensation method.     

Automated inspection of engineering ceramic grinding surface damage based on image recognition

As the engineering ceramic ground workpieces usually contain machining damage such as breaks and cracks, the traditional test methods cannot accurately reflect the real surface. Therefore, this paper describes an automatic damage detection system of the engineering ceramic machined surface using image processing techniques, pattern recognition, and machine vision. First, it has great influence on the exact identification of surface damage if engineering ceramic machined surfaces contain grinding texture, so Fourier transform is skillfully adopted to remove grinding texture. Second, through image noise reduction, contrast enhancement, and image segmentation, an optimal combination of image preprocessing is obtained. Then, by comprehensive extraction of surface feature parameters, decision tree classifier based on the C4.5 algorithm is built according to shape features and texture features. Finally, the paper achieves automatic extraction and classification of engineering ceramic grinding surface damage, and the recognition accuracy of breakage reaches over 93 %. Experimental results show that this method is effective in defect detection of the engineering ceramic surface, and it also can provide some analytical basis for the post-function hierarchy partition of engineering ceramic workpieces.     

PC机与数控机床CNC系统通信

介绍通用微型机（ＰＣ）与数控机床ＣＮＣ系统之间通信的具体实现方法，完成数控加工程序的直接输入／输出。实践表明该方法具有理想的应用效果。     

用于非圆表面磨削加工的高速数控磨床设计

利用PMAC（Programmable Multi-Axis Controller）-PC开放式数控系统作为核心控制器，设计集成了一台新型高速精密磨床。探讨了直线电机的伺服控制技术和电主轴单元的设计制造等问题；通过高速磨削实验研究，分析了整机的动态性能；应用PMAC时基控制法，实现了对椭圆零件的高速精密加工，为非圆截面工件的精密磨削加工提供了好的解决方案，推动了高速磨削加工新技术的发展。     

压光齿圆拉刀的设计改进

由于原压光齿圆拉刀在结构设计方面不够合理因而影响了被加工工件的尺寸精度和表面质量。通过改进压光齿圆拉刀的结构设计,从而大大地提高了被加工工件的表面质量。     

Mapping and compensation of geometric errors of a machine tool at different constant ambient temperatures

Thermo-mechanical effects due to changes in the ambient temperature on the shop floor and internal heat sources caused by the manufacturing process significantly contribute to the geometric deviations of a machine tool and therefore, the geometric deviations of the manufactured workpiece. Minimizing these thermally induced geometric deviations is worthwhile since the requested tolerances of machined workpieces become continually smaller nowadays. To investigate the overall deformations of a machine tool structure due to variations in ambient temperature the geometric errors of a five-axis machine tool at different ambient temperatures by means of a portable climate simulation chamber are systematically mapped. While positioning and squareness errors of the linear axes are significantly influenced by the ambient temperature, straightness as well as rotational errors were less sensitive to temperature effects. For the investigated machine tool errors of the two rotational axes are negligible due to an active cooling of these axes. Through numerical error compensation of the linear axes, the geometric errors of the investigated machine tool can be reduced up to 80%. Finally, an outlook how a temperature-dependent compensation could be derived from previously measured compensation fields at discrete temperatures and afterwards applied on-the-fly during manufacturing is given.     

并联机床加工性能的实验研究

研究和验证了BJ-04-2(A)型并联机床的加工精度与加工表面粗糙度。研究手段是选择国家标准样件进行加工实验,样件加工采用一次装夹,运用端面铣削、侧刃铣削、钻削和镗削的方法加工而成。实验数据结果的分析表明,BJ-04-02(A)型并联机床加工精度中,直线度基本满足国家标准的要求,其它精度指标则未达到标准的要求,加工的表面粗糙度相当令人满意。     

SUPPRESSION OF PERIOD DOUBLING CHATTER IN HIGH-SPEED MILLING BY SPINDLE SPEED VARIATION

Spindle speed variation is a well known technique to suppress regenerative machine tool vibrations, but it is usually considered to be effective only for low spindle speeds. In the current paper, spindle speed variation is applied to the high speed milling process, at the spindle speeds where the constant speed cutting results in period doubling chatter. The stability analysis of triangular and sinusoidal shape variations is made numerically with the semi-discretization method. It is shown that the milling process can be stabilized by increasing the amplitude of the spindle speed variation, while the frequency of the variation has no significant effect on the dynamic behaviour. The results are validated by experiments. Based on the analysis of the machined workpieces, it is shown that the surface roughness can also be decreased by the spindle speed variation technique.