局部装配

A method of local matching of assembly models is proposed, which is based on subgraph isomorphism and case matching.

为此提出一种基于子图同构与事例匹配的装配体局部结构相似性分析方法。

In mathematics , a topological space with a family of local coordinate systems related to each other by certain classes of coordinate transformations.

数学中指装配了一族局部坐标系的拓扑空间，这些局部坐标系之间由特定的坐标变换相互联系。

In mathematics, a topological space with a family of local coordinate systems related to each other by certain classes of coordinate transformation s.

数学中指装配了一族局部坐标系的拓扑空间，这些局部坐标系之间由特定的坐标变换相互联系。

The constitution mode and inclusion information of assembly drawings has been analyzed according to the expression contents and demand of rolling mill assembly drawings. The dendriform assembly model has been setup to express the assembly drawings contents. Under AutoCAD graphic environment, assembly drawings are realized with parts consolidation technology. Generating of local view, dimensioning, technical requirement, expression of list and title panel has been realized too. Generating of parts has been discussed and processing strategy of parametric drawings has been pointed out.

根据轧机装配图的表达的内容和要求，分析装配图的构成方式和应包含的信息，提出了建立树状装配模型来表达装配图的内容，基于AutoCAD图形环境，采用了用零件图拼装实现装配图生成的解决方案，并实现了装配图中有关局部视图的生成、尺寸标注、技术要求、标题栏和明细表的表达，并讨论了零件图的生成问题，提出了参数化绘图数据的处理策略，即利用PDB可编程对话框工具，设计了零部件的参数化编程框架，完成了工作辊、支承辊、机架等零部件的参数化编程。

The assembly of journal and plain bearing liner space is too little, force of organic still oil pressure is small it is the crucial index that affects lubricant result, make lubricate because of lacking engine oil between crankshaft and plain bearing liner and bite dead invalidation, include to be pulled badly, lack lube, layer of alloy of dry attrition generation is fused, grind sliding surface to did not maintain the oily film of certain ply, and all sorts of local overload exhaustion are destroyed, cavitation erosion and V form are destroyed etc, through technology of him director diesel locomotive old experience reachs the analysis of pair of its breakdown reasons, put forward precautionary measures especially. As a result of,the burns caustic mechanism plain bearing liner to burn caustic mechanism of 1 plain bearing liner is the lube film burst between journal and plain bearing liner, cause plain bearing liner and crankshaft generation clash, below high temperature, high pressure and high rotate speed, the wear-resisting alloy layer of plain bearing liner wears away prematurely or fuse, cause plain bearing liner and crankshaft to stick thereby bite, can make the steel back of plain bearing liner and Kong Zhong produces whirligig, inlet port is jammed, carry on the back by steel again with the friction of aperture causes high temperature to make plain bearing liner burned-out further, can cause bolt to break off, happen swing a malign accident that pounds cylinder body of bad internal-combustion engine.

轴颈和轴瓦的装配间隙太小，还有机油压力低是影响润滑效果的关键指标，使得曲轴和轴瓦之间因缺少机油润滑而咬死失效，包括严重拉伤，缺少润滑油，干摩擦产生合金层熔化，磨滑面没有保持一定厚度的油膜，以及各种局部过载疲惫破坏，气蚀和V形破坏等，通过本人主管内燃机车技术多年经验及对其故障原因的分析，特提出预防办法。1轴瓦的烧损机理轴瓦烧损的机理是由于轴颈和轴瓦之间的润滑油膜破裂，导致轴瓦和曲轴产生摩擦，在高温、高压和高转速下，轴瓦的耐磨合金层过早地磨损或熔化，从而引起轴瓦和曲轴粘咬，会使轴瓦的钢背和座孔中产生旋转运动，进油孔被堵塞，再由钢背和座孔的磨擦进一步引起高温使轴瓦烧坏，并会造成螺栓折断，发生甩出捣坏内燃机缸体的恶性事故。

The new rT joint not only has two rotation axes that intersect at right angle,but also has another rotational degree of freedom which can be used to modify the assembly of other joints.This can change the mobility of the parallel mechanisms that assembled with the new rT joints and leads to two types of metamorphic paralllel mechanisms:In the first type,the mechanism changes its topology by turning the new rT joints in all limbs into different configurations which reconfigures the constraints within the limbs or the assembly of all the limb constraints.This change of mobility is completed by two cases.One is illustrated by a 3PS and a 3C parallel mechanism,by altering the rT joint into different configurations there will produce or reduce local degrees of freedom and thus change the constraits to the moving platform.This qualifies the 3PS and 3C to have variable mobility from 3 through to 6 and from 1 through to 6 respectively.

该铰链除了一般Hooke铰的两个轴线互相垂直相交的旋转自由度外，还增加了一个可以调节该两个轴线之一的姿态的一个旋转自由度，通过此自由度调节该rT铰到不同的装配构型，可以改变用其装配的并联机构的自由度，由此产生两类新型的并联变胞机构：一类是机构的各个支链中都有rT铰，该铰链的不同构型可以改变各支链对运动平台的约束或整个支链组的组合形式而改变机构的自由度状态，3PS和3C属于前者，通过调节rT铰到不同构型可以使其支链产生或消失局部自由度，从而减少或增加支链对运动平台的约束，使得并联变胞机构3PS和3C分别具有自由度从3变到6和从1变到6的能力；3P属于改变支链组组合形式的机构，其rT铰的不同构型将改变整个支链组的几何约束组合，使得并联变胞机构3P可以有三转动、三平动或三平移(来源：ABCded9de论文网www.abclunwen.com)一转动的自由度形式。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。