在车床上镗削变速箱孔系的三工位夹具

介绍一种变速箱镗孔夹具的设计及使用方法。该夹具构思新颖，使箱体部件一次安装，可以在三个工位上加工三个孔系，保证了变速箱体的加工精度及孔系之间的平行度，实际使用已取得较满意的效果。     

拨叉两平面磨削夹具设计

我公司是压路机专业生产企业,变速箱是压路机上的一个关键部件,而拨叉又是变速箱里换向或变速的关键零件,设计和加工精度要求高。该拨叉两平面不仅自身有较高的平行度要求,而且相对于孔中心线还有严格的垂直度要求,加工起来难于保证。为此,我们设计了一套磨削夹具在平面磨床上进行加工。     

系列拨叉轴圆弧槽铣夹具的设计与制造

根据变速箱拨叉轴上圆弧槽相对位置准确、系列拨叉轴可以在一套夹具上装夹、多个零件同时加工的加工要求,设计了一种分体式气动铣床夹具。夹具采用定位块限位拨叉轴端面、燕尾面支承拨叉轴外圆的定位方式,工件外圆多点气动夹紧。通过两级增力机构,增大夹紧力。柔性传动力矩,消除了交变铣削力作用下产生的振动。依据切削力的计算选择了气缸规格。本设计实现了工件在夹具中成组布置,提高了生产效率,保证了加工质量。     

汽车变速箱输入轴加工夹具的缺陷分析与优化改造

加工夹具经常应用于变速器输入轴内外圆的磨削作业,针对工件磨削完成后总是出现无法正常放松的情况,分析认为是由于加工夹具存在缺陷导致。为了解决汽车变速箱输入轴加工夹具存在的缺陷,对导致夹具出现缺陷的原因进行了详细分析,并在此基础上自主开发了一种放松气缸结构对原有的夹具进行了优化改造。从现场检验结果来看,优化后的夹具可以满足生产需求,原有的缺陷得到了很好的解决。     

高精度回转式钻模

我厂生产的叉车变速箱上盖(图1),两侧6-16D9孔的尺寸精度及形位公差要求较高,采用常规夹具在钻床和镗床上加工很困难。因此,我们设计制造了一种高精度回转式钻模(图2)。夹具本身要求精度较高,例如:夹具体1上的60H7、32H7的形位及     

加工中心用夹具的改进

一、使用原有夹具存在的问题我厂在变速箱壳体生产线采用了NCV-50A立式加工中心,加工壳体轴承孔,壳体由工艺孔定位在夹具上,如图1所示。加工中心是通过程序控制工作台在X、Y方向移动和主轴在Z向的运动,实现对工件上不同位置孔的加工。因此,对某种壳体每次加工前都。必须确定壳体夹具坐标系O’X’Y’Z’相对于加工中心坐标系OXYZ的坐标位置,并把确定的数据输入加工中心程序中,才能完成精确的加工,对于用工艺孔定位的壳体夹具,即必须确定夹具上定位销与加工中心坐标原点O的坐标位置关系,才能保证壳体上工艺孔与轴承孔之间的…     

轻型变速箱箱体加工线对多种箱体实现高效生产

介绍了大同齿轮有限公司新建轻型变速箱箱体加工线,通过模块化夹具设计及高速加工,使单条生产线实现多种箱体的快速换产和高效加工.     

扩大 Y54插齿机使用范围的实践

近几年在加工瑞典与西德汽车变速箱齿轮和花键套等备件中,零件型号较多,结构特殊,为适应加工的需要,我们改革了工艺方法,取得了较好效果。加工变速箱换档套,其内花键为四或六个矩形键槽。若拉削成型, 需制造拉刀和分度夹具,而刨或插     

变速箱齿座的两面铣夹具设计

齿座为变速箱的重要零件之一，因其数量大，在实际生产中提高加工效率显得尤为重要，又因品种较多，夹具的设计须考虑通用性。根据客户要求，在此道工序我们完成工件Ф80mm圆弧面的加工。     

一种高精度新型轴类滚齿工装的设计

变速箱是汽车上的重要部件,其通过不同的齿轮组合产生变速变矩,从而改变传动比,实现档位调整。变速器中轴类产品齿部精度要求普遍都很高,因为它直接影响汽车变速箱甚至整车的性能。目前,变速器轴类产品滚齿部分的加工中,滚齿机上采用的夹具加工齿跳等齿部参数不稳定。因此,本文介绍一种变速箱的轴类件高精度新型滚齿工装的设计思路,从工装的角度出发,有效地保证滚齿序轴类零件的加工精度及质量稳定性。     

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.     

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....     

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.     

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.