U形冰箱门壳钣金成型自动化设备研究

针对传统钣金成型生产效率低、产品质量差的问题,在对U形冰箱门壳的产品成型工艺路线分析基础上,设计了轧辊成型工位、打Z工位和下料机械手工位的机械结构。提出了主要工位的作业动作流程,阐述了电气控制系统的工作原理;采用多组辊轮渐变成型方式,实现了复杂槽型的成型;采用吸盘式气动下料机械手方案,完成了大尺寸钣金件的平稳下料;采用Profibus-DP总线技术和西门子S7-300PLC,设计了生产流水线自动控制原理图,实现了生产设备的自动化生产。研究结果表明:设备生产节拍不大于35 s/套,废品率低于0.1%,产品外观美观,尺寸精度满足使用要求。     

国内多工位冲压生产线的主要形式

正多工位冲压生产线是压力机、多工位模具、快速换模系统、上料系统、送料系统、电气控制及网络控制系统的集成,其相对于单机生产或者多机连线生产的最大特点就是:压力机在完成一次冲压后,不需要停在上死点等待送料机械手进行工位间移送,而是压力机连续工作,同时送料机械手进行工位间移送,即以连续冲程工作,取代单机单次工作方式,提高了生产效率,降低了设备的故障率,减少了操作人员及工作场地的使用。     

基于MIDAS U型荧光灯接桥机工位机械手模态分析

接桥机工位机械手是U型灯管接桥的重要部件,为了提高荧光灯的性能和产品一致性,对接桥机工位机械手进行了优化和改进。应用SolidWorks软件对接桥机及其工位机械手进行实体建模。通过MIDAS软件对工位机械手模型进行模态分析,根据分析结果对工位机械手加以改进。与原工位机械手相比,改进后的工位机械手变形比例减小15.24%,最大变形量减小11.50%。通过生产试验数据表明,产品合格率达到了90%以上,产品的一致性也有显著提高。     

十三、油泵凸轮轴自动线机械手

上海柴油机厂广大革命职工在毛主席革命路线的指引下,随着生产率的大幅度发展,机械化及自动化程度得到很大提高,所以机械手在该厂生产中较早得到应用,在1958年该厂油泵车间工人师傅与技术人员遵照伟大领袖毛主席关于“人民群众有无限的创造力”的教导,首先设计,制造了机械手,作为喷油咀体自动上料及输送之用,效果良好。但由于修正主义企业路线的影响,自动化的发展有所停滞。文化大革命期间,广大革命职工冲垮了修正主义企业路线的束缚,自动上下料及机械手的应用又得到很大的发展,在喷油器体加工自动线、曲拐加工自动线、油泵凸轮轴加工自动线等设备上,都先后应用了机械手作为上下料及工位间之传递,在热加工方面连杆锻造生产流水线也应用机械手作为工位间输送。下面我们将介绍上海柴油机厂XSC06喷油器体上料装置,油泵凸轮轴自动线机械手及曲拐自动加工机械手。     

物料搬运机械手结构设计试验

传统的人工搬运已不能满足现有的生产规模。通过机械手实现物料搬运已成为一个重要的课题。针对3自由度物料搬运机械手,重点阐述机械手手部、手腕、手臂及立柱的设计,通过对手爪、手腕及立柱进行分析,采用单支点回转型手爪、回转气缸驱动手腕以及升降和回转气缸驱动立柱,可实现将正在加工的产品从一个工位移动到另一个工位。所涉及的机械手可代替人类进行物料搬运,提高工作效率。     

冲压上下料机械手控制系统设计

冲压上下料设备具有两个机械手,可以同步水平右转或左转、垂直上升或下降,实现冲压生产中上料、下料的自动化。文章设计了以可编程逻辑控制器（Programmable Logic Controller,PLC）为核心的机械手控制系统,它包括触摸屏、伺服驱动和气动控制等。系统设有手动和自动两种工作模式。在自动模式下,一个机械手取走加工好的工件并放置在成品区,另一个机械手同步将待加工的工件从送料台上取走并精确放置到工位。该机械手装置已投入实际应用,具有动作精度高且安全性强的优点,既提高了生产效率,又减轻了劳动强度。     

一种大缸径气缸套毛坯生产线的设计

本文设计了一种大缸径气缸套毛坯生产线,主体为八工位浇注机,其上设置有四个动力头,浇注机的周围呈正八边形设置有八个工位。工位一设置有浇火装置,工位二、三、四为激水工位,工位五、六、七分别设置有拔毛坯装置、拨飞锤装置和模具清刷装置、模具喷涂装置。毛坯拔出后经风冷装置及毛坯清刷装置再由多关节机械手放入毛坯筐。挡板由多关节机械手取出后经过挡板清刷喷涂装置处理后再装入模具。该生产线自动化程度高,占地面积小,生产效率得到大幅提高。     

汽车轴承自动搬运装置的研制及应用

为了解决汽车轴承生产线上多个工位间的自动化生产问题，研制了一种适用于多种型号汽车轴承的自动搬运机械手装置。依据设计指标与原则，对其整体结构进行了三维建模设计并对关键零部件进行了有限元分析；然后对控制系统进行了整体规划；将研制出的设备应用到了企业现场，进行了实际生产。统计结果表明，设备运行稳定，满足各项要求，成功达到了预期目标，验证了设计的合理性与可靠性。     

基于 PLC 的自动续料机械手

介绍了一种基于PLC控制的新型自动续料机械手结构。该装置应用于冲压生产过程中对各工位自动续料。对该装置的主要机械结构、动作方式、电气控制原理、控制方式做了详细的表述。     

基于PLC的气动机械手控制系统设计与研究

该文设计了一套小型的用来放置变送器的立体框架,它采用了PLC控制的气动机械手将准备进行高低温补偿的变送器,放置到框架上下两层的各工位上。在详细研究了气动机械手的结构、动作循环及工作原理之后,根据该气动机械手的工作流程,设计了气压传动系统和PLC控制系统。包括气动原理的制定、气动元件的选择以及PLC选型和顺序功能图的编写。气动机械手采用多位置气缸,以实现机械手在框架每层各工位之间的操作;并使机械手操作气缸沿立柱上下运动,以实现机械手在上下两层之间的操作。     

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...     

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.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

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...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.