印刷机高点闭牙机构动力性能改善方法研究

针对印刷机高点闭牙机构在高速时的冲击、噪声问题,给出了高点闭牙机构动力性能分析及改善的一般方法,建立了通用的分析方程;并结合某型号印刷机高点闭牙机构进行了实例分析,揭示了机构的动力性能及存在的缺陷.在此基础上,对此机构进行了动力性能改善,改善后机构的角加速度、接触力、铰支力平稳、无突变,角加速度峰值降低了62%,明显的改善了高点闭牙机构的动力性能.     

固定凸轮的摆动从动件凸轮机构运动特性分析方法

根据固定凸轮的摆动从动件凸轮机构的运动特点,提出了该机构运动特性分析的一般方法,建立了通用的分析方程,并将该方法应用于印刷机的高点闭牙机构的设计中,揭示了该机构的运动性能及存在问题,分析结果与实际情况一致,验证了该方法的正确性及优越性.     

三次样条插值函数在凸轮机构运动分析中的应用

凸轮机构的运动分析在机械优化设计中具有重要的研究价值。本文对目前常用的几种凸轮机构运动分析方法进行了评价,指出了其不足和存在的问题,然后将三次样条函数应用于凸轮机构的运动分析中,建立了基于三次样条函数的凸轮机构运动分析方程,最后以印刷机的开闭牙凸轮机构为例,实现了其完整的运动分析,仿真结果验证了方法的正确性及优越性。     

MW1050Ⅱ自动模切机叼纸牙排定位性能优化

为进一步提高MW1050Ⅱ自动模切机的工作速度和精度,对自动模切机的重要机构后靠规定位机构和叼纸牙排的运动规律(位移、速度、加速度)进行了研究,分析了后靠规从动件对叼纸牙排产生冲击的原因,对原后靠规机构从动件运动规律进行了优化设计.优化结果表明后靠规从动件对叼纸牙排产生的冲击、噪声大大减小.     

锡膏印刷机印刷系统的误差分析与补偿

为了减小或消除全自动视觉锡膏印刷机的印刷系统误差,在介绍了锡膏印刷机系统的组成和功能的基础上,通过分析运动机构产生系统误差的原因和作用过程,针对平台运动机构误差做了定量分析,并对平台运动机构进行了误差测试,根据测试得到的结果数据,设计了一种减小印刷系统误差的补偿方案。实验结果表明,对印刷系统的误差测试与分析是合理的,所建立的印刷系统的误差模型准确可靠,对运动精度的分析和实际生产装配有一定的指导意义。     

CAXA在机械设计中的应用三例

1．CAXA在机构运动分析中的应用 用矢量方程图解法进行机构的速度及加速度分析时,如何快速准确地根据矢量方程式绘制出机构的速度多边形和加速度多边形是个待解决的问题。由于速度多边形和加速度多边形中的“边”与机构运动简图中构件的方向相垂直或平行,因此,运用CAXA的“绘制角度线、法线／切线”功能可方便地完成作图,     

UG在机构运动分析应用中关键技术的研究

对利用UG软件的运动分析模块在机构运动分析应用中的关键技术进行了研究,结果表明能够很方便地利用UG软件的运动分析模块分析机构中任意部件在任意位置时的位移、速度和加速度等运行特性,避免了传统的复杂的理论分析过程,提高了机构运动分析的效率.     

机构运动误差分析方法及其运用

建立了机构运动误差分析的一般方法,具有一定的普遍性和综合性,并据此导出了曲柄滑块机构、移动从动件盘形凸轮机构的运动误差分析公式.     

连续采煤机补偿凸轮机构的运动学分析

为了提高连续采煤机补偿凸轮机构的设计质量,对其工作机构的运动学行为进行了深入研究.根据煤矿井下实际工作条件,分析了该机构的补偿工作原理和运动特性,建立了该机构从动件的摆动理论模型和平动理论模型.并且通过计算机模拟仿真,验证了理论模型的正确性.最后根据仿真结果,分析了从动件各运动参数随时间的变化规律,确定了从动件在运动过程中对相关零部件的冲击时刻点和冲击规律.为合理选择该机构的工作参数提供了科学理论依据.     

作复杂相对摆动构件--凸轮机构优化设计

提出了具有复杂相对运动的摆动构件一平面凸轮机构中摆动轴心和运动输出点的运动规律求解方法，以及固定凸轮廓线设计原理，据此对印刷模切机后靠规定位机构中定位运动打击点和固定凸轮廓线进行了优化设计。优化结果表明后靠规定位机构的运动、动态性能得到了很大改善，定位过程产生的冲击、噪声大大减小。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

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.     

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.     

Fifth International Summer School on Screw-Theory Based Methods in Robotics

正3-11 September,2014University of Bologna,Bologna,Italy www.summerscrews.org summerscrews2014.ing.unibo.it SUMMER 20SCREWS 14In 2014,our screw-theory school comes to the world's oldest university.In early September,Summer Screws'14 will gather six experts in the application of screw theory in robotics and up to 40 participants at the University of Bologna,Bologna,Italy.The school will teach attendees how to apply existing methods and empower them to develop new ones in their own research.The basic theoretical notions will be introduced in a rigorous manner,emphasizing examples,applications,and exercises.Scholarships are available.     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

INDUSTRIAL ENGINEERING AND VISUALISATION-A PRODUCT DEVELOPMENT PERSPECTIVE

Taking the actual project of teaching and researching process for example, the relationship between the industrial engineering and product development is discussed. And use the novel visualization technology to support the industrial engineering and product development. How to use the new computer modeling and simulating technologies to support the product development and industrial engineering, is introduced especially. The support includes both domestic products and industrial systems. The visualization and computer technologies take a very important role in some system or multi-direction modeling, those technologies mentioned above can help the industrial engineers study the effect of design on the whole life circle, including the producing steps. So the engineers can avoid making the wrong decision which may cause bad effects on the whole industrial engineering.     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...