十字滑块联轴器的运动及动力特性分析

用解析的方法对“十字滑块联轴器”中的构件“十字滑块”的运动规律、速度、加速度进行了分析,得出了其运动规律及描述公式,清楚地描述和分析了其运动特性;在上述运动分析的基础上,进而分析了“十字滑块”的惯性力、摩擦力的分布及变化规律和机械效率的影响因素及变化规律,以期对“十字滑块联轴器”的运动及动力特性有深入的理解,并对大功率“十字滑块联轴器”的设计和选型提供更精确的理论支持。     

弧面十字滑块联轴器的设计与研究

十字滑块联轴器可补偿安装及运转时两轴间的相对位移,但是要求主动轴与从动轴之间不能存在夹角,且在工作时,如果两轴间发生相对位移,中间盘就会产生很大的离心力,从而增大动载荷及磨损,降低联轴器的使用寿命。针对这个问题,利用TRIZ理论对其分析,设计出一种弧面十字滑块联轴器。参考SL70型十字滑块联轴器的技术参数,运用Pro/E和ANSYS Workbench软件,对新型联轴器进行三维建模和装配并进行了静力学分析。研究表明,在传递相同的公称转矩下,弧面十字滑块联轴器满足强刚度要求。     

十字滑块联轴器的改进

用于传动机构中的十字滑块联轴器,在更换易损的十字滑块、轴承等零件时,因没有轴向移动空间,必须将主、被动件分离.有的主、被动件较重,需吊装工具拆装.为了克服此缺点,我们改进了十字滑块.将原先的一块十字滑块改为两片(块),放入联轴器中用螺栓连接紧固(见图1).要根据负载大小来确定两片十字滑块的厚度和连接螺栓的大小及个数.为了提高联轴器刚度,联轴器用45~#钢,十字滑块用Q235A普通碳素钢.     

安全型十字滑块联轴器

我厂有台六轴立式镗床,采用弹性圆柱销联轴器(图1)传动。使用时,由于切削余量大,发现联轴器的弹性销容易剪切损坏,约两月就需更换。若改用普通型十字滑块联轴器,增加了强度和刚性,但传动箱齿轮容易打牙,主轴上平键被剪切。为此,我设计了一种安全型十字滑块联轴器(见图2),装上后使用效果良好。下面介绍联轴器特点。     

联轴器的特征造型及基于装配关系的相关设计

运用inventor 10软件对十字滑块联轴器进行了特征造型和基于装配关系的零件的相关设计，分析了三维模型建立的过程和基于装配关系的事件相关设计的技术要点，生成了联轴器的工程图，这样就大大提高了产品标准化和系列化设计的效率。同时也对inventor 10软件在其他产品设计中的应用有很重要的指导意义。     

自润滑十字滑块联轴器

十字滑块联轴器是两轴联接一同回转以传递运动和动力,并兼有补偿两轴的径向位移、轴向位移、角位移与改善传动系统特性等作用,它是依靠十字滑块在半联轴器凹槽中的滑动来补偿被联接两轴安装时的对中误差和工作时的相对位移,避免或减轻附加载荷。当两轴轴线位移过大时,附加载荷会显著增大,摩擦力也随之增大,十字滑块联轴器摩擦磨损加剧。为减轻摩擦磨损,十字滑块上常装有压注油杯,以保证其很好的润滑。 然而十字滑块上装压注油杯,不仅会使其结构复杂,另外需人工经常向压注油杯加注润滑油,有时会因结构关系而润滑不良,影响联轴器的使用性能和寿命,某些精密机械传动甚至不能满足精度要求。自润滑十字滑块联轴器,则无需压注油杯,也无需加润滑油,完全靠材料的自润滑性能减少摩擦磨损,并能满足精密传动使用要求。现介绍如下。     

一种十字滑块联轴器的设计改进

十字滑块联轴器是一种可移式的刚性联轴器,所需安装空间小,可补偿两轴间的径向偏移,适用于雷达数据传动链中同步轮系轴微电动机轴的联接。但在实际使用过程中,由于受材料、公差、半联轴器与轴的夹紧方式等因素的影响,会出现联轴器无法正常工作,甚至损坏微电动机的现象。通过进行一种同步轮系用十字滑块联轴器的运动过程仿真和受力分析计算,得出了满足疲劳强度所允许的两轴间的径向偏移,反映出滑动灵活对保证联轴器正常工作的重要性。在初始设计的基础上,分析了所用十字滑块联轴器使用过程中存在的问题,从零件的形状、选择的材料和螺钉的品种等3个方面分别采取措施进行了设计改进,改进后的联轴器滑动灵活性得到了有效提高,取得了良好的实际使用效果。     

十字滑块的数控加工工艺装备设计

分析了十字滑块的加工精度要求,制定了合理的工艺路线,详细说明了胎模的设计、加工、检测及使用方法,保证了十字滑块凸榫和联轴器凹槽之间的配合精度,解决了加工难题,提高了机械加工工艺水平,为今后加工该类产品提供了借鉴经验。     

15 t门座起重机倾翻事故分析

在对15t门座起重机倾翻事故进行深入分析中，指出起重机设计和使用中应注意的事项。并通过对浮动联轴器十字滑块有限元分析计算，找出其薄弱环节，为以后的设计提供了科学依据。     

十字滑块联轴器的改进设备

十字滑块联轴器的失效形式主要为挤压变形,传力的接触面变形后需要整体更换,一是材料利用不充分,二是工作量大.本文提出了双槽半联轴器的设计方案,不仅使其寿命延长近一倍,而且大大减少了维修工作量.     

Process Quality Analysis of Products

Process capability indices are widely regarded as a flexible means of evaluating the quality and performance of a process. Accreditation by the Quality System Requirement QS9000 requires an agent to conduct a global evaluation on the process capability over the entire product family from a plant. Generally, the process capability of the whole product family is an important reference for evaluation when producing a new product or designing a new process. Therefore developing a scheme to evaluate the process capability of the whole product family or series is crucial for industry. This paper takes the production of capacitors as an example of a new method for evaluating the process capability of a whole product family. As the quality characteristic for producing capacitors is "the smaller the better", the upper specification limits of the capacitors of various specifications should first be established. The process capability index Cpu for products for which "smaller is better" is then used as an evaluation tool to calculate the process capability indices for individual specified products. The relationship between the process capability indices and the yield will be studied. A process capability index is proposed to reflect the global yield of the whole product family and to serve as a reference for evaluating process capability for designing new processes or developing new products. The process capabilities for all products can thus be evaluated and the performance of each process can be evaluated according to the colour management method. Managers can determine easily whether products meet their specifications and take action to improve them if necessary, according to the colour management method.     

用于磨削面齿轮的蜗杆砂轮修整方法研究

为了实现面齿轮磨齿加工,采用包络原理对面齿轮磨削蜗杆砂轮齿形进行设计,并对蜗杆砂轮的修整方法进行研究.建立了蜗杆砂轮齿面的包络坐标系;给出了蜗杆砂轮产形面方程;推导了蜗杆砂轮齿廓的曲面方程,利用Matlab软件对蜗杆砂轮齿廓进行了仿真,根据面齿轮磨削蜗杆砂轮的齿面生成原理,给出了修整工具的齿廓形状、齿宽限制以及修整工具...     

Automated inspection of PCB components using a genetic algorithm template-matching approach

Automated inspection of surface mount PCB boards is a requirement to assure quality and to reduce manufacturing scrap costs and rework. This paper investigates methodologies for locating and identifying multiple objects in images used for surface mount device inspection. One of the main challenges for surface mount device inspection is component placement inspection. Component placement errors such as missing, misaligned or incorrectly rotated components are a major cause of defects and need to be detected before and after the solder reflow process. This paper focuses on automated object-recognition techniques for locating multiple objects using grey-model fitting for producing a generalised template for a set of components. The work uses the normalised cross correlation (NCC) template-matching approach and examines a method for constraining the search space to reduce computational calculations. The search for template positions has been performed exhaustively and by using a genetic algorithm. Experimental results using a typical PCB image are reported.     

虚拟企业环境下制造合作伙伴选择决策方法研究

在虚拟企业环境下，为了实现敏捷制造低成本、高效率的运作，企业应该将产品进行适当分类，并以此作为选取制造合作伙伴的基本条件。从制造成本的经济性考虑，借助于映射集方法，依照特定的条件和规则，将种类繁多的待生产零件进行映射分类，建立了相应的模型。为解决供应链合作伙伴的选择问题，运用理想解类似度偏好顺序评估法建立了多目标决策的算法模型，并结合产品研发过程进行了实例分析计算，取得了理想合作伙伴的选择结果。该结果能客观反映实际情况，对企业进行敏捷制造实现优化的生产组织具有指导意义。     

Infrared image system for fire location

This paper describes a new sensor and interpolation technique for localizing a fire in a closed environment or in a highway tunnel. When a smoke detecting device warns for a presence of a fire, two thermopile arrays images are elaborated, to localize the, eventual, fire and to control fire extinguisher jet. This system is a very promising for highway tunnel and also as substitute for common fire sprinkler systems in closed rooms, due to its cost and relatively simplicity of installation.     

Generalized solution for predicting relaxation from creep in soft tissue: Application to ligament

Creep and relaxation are two viscoelastic phenomena that are easily interrelated for a linearly viscoelastic material, but interrelationships are complex for nonlinearly viscoelastic materials. We use a single-integral nonlinear superposition principle to relate creep and relaxation, where the kernel is assumed to be a nonseparable product of strain and time. Herein, we develop time dependence as general power laws with up to four terms for creep compliance and relaxation modulus. Higher-order formulations give better results for ligament in terms of curve fitting and prediction of relaxation from creep. This is illustrated by a comparison between a two- and a three-term formulation on the experimental data of rabbit medial collateral ligaments. Also, an interrelation between several aspects of creep and relaxation is presented for arbitrarily high order, and the nature of high-order interrelation is discussed. The generality of the method makes it suitable to phenomenologically model many complex materials, to predict complex behaviors and to therefore reduce the amount of testing for robust material characterization.     

Capsule-supporting ring: a new device for resin embedding of glass-mounted specimens

The goal of specimen preparation for transmission electron microscopy is to obtain high-quality ultra-thin sections with which we can correlate cellular structure to physiological function. In this study, we newly developed a capsule-supporting ring that can be useful for resin embedding of glass-mounted specimens. The present device allowed us to re-embed a semi-thin section on a microscope slide into a resin block not only for efficient ultra-thin sectioning but also for a correlative light and electron microscopy. Similar to epoxy resins for morphological observations, semi-thin sections of low-viscosity hydrophilic resins, such as Lowicryl series, can be re-embedded into the resin, which can be useful for cytochemical gold labelling. A further application of the present device improved flat embedding of cultured cells on glass cover slips for electron microscopy, preserving in situ sub-cellular structures close to their native state. We practically describe the use of capsule-supporting ring and demonstrate representative micrographs as results.     

Registration and Data Merging for Multiple Sets of Scan Data

It is generally necessary in 3D scanning to divide a wrap-around object into several regions, each of which is measured individually. A series of pre-processing procedures must be implemented to prepare the data for use for surface reconstruction. Registration is a procedure for unifying the coordinate systems for multiple sets of scan data. Three registration algorithms, 3 points to 3 points, 3 spheres to 3 spheres and 3 planes to 3 planes, are proposed to suit different applications. Data merging is a procedure for removing overlapping data for multiple sets of scan data and for merging them into one set. A data search algorithm, based on triangulation, is com-bined with a few merging rules to merge the data in terms of different needs. Several experimental results are presented to demonstrate the feasibility of the proposed algorithm.     

An Assessment Framework for Optimal FMS Effectiveness

Equipment failures in an FMS are significant to performance and can lead to costly, incorrect decisions. Fortunately, effectiveness measurement techniques can be mapped to clever modeling frameworks to help predict, track, and then improve upon the FMS performability or mission effectiveness, and improve maintenance. This article provides sources and guidelines for efficient and effective FMS modeling, a framework for applying the modeling to predict the impact on customers from their point of view, and a method for tying it all together for improving the FMS effectiveness. It is not enough to simply examine the working and failed states of an FMS or even to calculate common reliability metrics. It is necessary to consider the FMS as a whole, and that system includes the needs of the customer and the business. It is also necessary to be purposeful about the measures of performance selected and to support the measures of effectiveness.In this article, we present: a framework for considering customer needs in the measures of effectiveness for FMS; modeling approaches for solving for effectiveness measures; and an example to show how to apply it to an FMS, to improve it or plan for meeting specific customer needs.     

Hybrid controller with observer for the estimation and rejection of disturbances

In this paper, a hybrid controller with observer is introduced for the estimation and rejection of a disturbance. It is based on the combination of the sliding mode technique and the output feedback strategy. It is divided into two designs: (1) the observer and (2) the controller with observer. The observer is selected to reach two objectives: (a) to assure its stability and (b) for the estimation of a disturbance. The controller with observer is selected to reach three objectives: (a) to assure its stability, (b) for the rejection of a disturbance, and (c) for the decreasing of chattering in the sliding mode behavior. The proposed method is applied for the estimation and rejection of the disturbance in a plotter and a suspension system.