基于计算机视觉的齿条测量方法研究

提出一种基于计算机视觉的齿条测量方法。建立一套计算机视觉的测量系统,系统把CCD摄像机安装于光栅反馈式精密导轨上,精密导轨带动CCD摄像头移动对齿条各处进行图像采集,通过对采集图像的处理,实现全齿的测量,获得齿条的基本参数如齿距p、齿厚s等数据。实验对指示表卡尺齿条进行测量,并与东京精密S1910DX3轮廓度仪的测量结果对比,结果表明,此方法的测量精度能满足该类齿条测量的要求。该测量方法简单实用,有效提高了卡尺齿条的测量效率,为卡尺齿条的在线检测提供技术保障。     

核电站拦污网主绳拉力监测与分析

为避免核电取水系统堵塞导致停堆或降低发电功率,需在取水口前布置拦污网。对拦污网主绳的拉力进行实时、连续、精确监测预警分析,可识别拦污网的工作状态,对核电站安全运行具有重要的意义。本文通过对拦污网主绳拉力进行连续监测,采用无线传输技术采集传输拉力信号,获得了主绳拉力的变化规律。在此基础上进一步分析了潮汐、海浪等因素对主绳拉力的影响,确定了对拉网造成较大影响的不利条件。监测结果表明海浪对拦污网拉力影响显著,拉力随潮汐呈周期性变化。     

走钢机行走小车的故障分析与改进设计

针对走钢机行走小车经常出现的减速机输出轴易弯曲、齿轮齿条易磨损等故障现象,从齿轮、齿条受力原理和行走小车的结构角度,提出了改进设计的方案。     

Optimal storage rack design for a 3-dimensional compact AS/RS

In this paper, we consider a newly designed compact three-dimensional automated storage and retrieval system (AS/RS). The system consists of an automated crane taking care of the pallets' movements in the horizontal and vertical direction. A gravity or powered conveying mechanism takes care of the pallets’ depth movement in the rack. Our research objective is to analyze the system performance and optimally dimension the system. For single-command cycles, the crane's expected retrieval travel time is the same for gravity and powered conveyors; we give a closed-form expression. From the expected travel time, we calculate the optimal ratio between three dimensions that minimizes the travel time for a random storage strategy. In addition, we derive an approximate travel time expression for dual command cycles for the system with powered and gravity conveyors, respectively, and use it to optimize the system dimensions. Finally, we illustrate the findings of the study by a practical example.     

整体式货架三维有限元分析

根据整体式货架的结构和承载特点,利用有限元分析软件ANSYS建立了其三维实体模型,在考虑了各种载荷的基础上,对其在各种载荷工况下的应力和位移进行了计算,为类似货架的设计计算提供了参考。     

Instrumental Design and Verification of a Nondestructive Testing with Neutron Backscattering for Boron-based Material Characteristics

The in-situ nondestructive testing (NDT) instrument using neutron backscattering for boron-based materials was developed successfully in this work. The capability verification of confirming qualitatively the integrity of the boron-based material as neutron absorber and characterizing quantitatively the gap defect size was demonstrated herein. For extending the technique at the fast traverse mode, a derived relationship between the defect size and output signal considering the effects of scanning speed and time constant was presented in this work for data interpretation. We also performed an experimental sensitivity analysis as a function of operation parameters. Through a comparison of the increase in output counting rate current between calculation and measurement, the deviation of the theoretical prediction at the fast traverse mode was within ±30%.     

三峡升船机齿条及螺母柱间隙灌浆工艺试验

为了选择出合适的灌浆材料和灌浆工艺并模拟升船机齿条、螺母柱间隙灌浆的实际情况,分别进行了灌浆工艺试验与原型灌浆试验。灌浆工艺试验对比了3种国产灌浆材料和德国PAGEL灌浆材料,试验结果表明德国PAGEL灌浆材料物理性能指标和力学性能指标优于国产灌浆材料。在原型灌浆试验中,对灌浆设备选型、搅拌时间、模板密封、灌浆方式、灌浆流速参数控制等方面进行了试验研究,优选出适用于三峡升船机齿条、螺母柱接缝灌浆的材料和合适的灌浆工艺。以上试验效果明显,解决了灌浆密封难度大、易堵管等施工难题。     

三峡升船机齿条和螺母柱一期埋件PVC 套管安装测量方法

介绍了三峡升船机齿条、螺母柱一期埋件PVC套管安装测量方法,并对安装测量精度进行估算。一期埋件PVC套管混凝土浇筑后的测量成果,二期埋件和设备安装的实际效果验证了PVC套管安装测量方法的可行。     

Optimization of asymmetric spur gear drives to improve the bending load capacity

In a given size of symmetric involute gear designed through conventional approach, as the load carrying capacity is restricted at the higher pressure angle due to tipping formation, the use of the asymmetric toothed gear to improve the fillet capacity in bending is examined in this study. Non-standard asymmetric rack cutters with required pressure angles and module are developed to generate the required pinion and gear of a drive with asymmetric involute surfaces and trochoidal fillet profiles. The respective profiles thus generated are optimized for balanced fillet stresses that are equal and possibly the lowest also. For this study of optimization, several non-standard asymmetric rack cutters are designed to accommodate different combinations in the values of pressure angle, top land thickness ratio, profile shift, speed ratio and the asymmetric factors. However for any drive with a given center distance and a speed ratio, only two non-standard asymmetric rack cutters, one for the pinion and other for the gear are used to generate a required numbers of pinion and gear with different cutter shift values for the purpose of optimization. The influence of these parameters on the maximum fillet stress has been analyzed to suggest the optimum values of these parameters that improve the fillet capacity in bending. The optimization of the asymmetric spur gear drive is carried out using an iterative procedure on the calculated maximum fillet stresses through FEM for different rack cutter shifts and finally the optimum values of rack cutter shifts are suggested for the given center distance and the speed ratio of an asymmetric gear drive. Comparisons have also been made successfully with the results of the AGMA and the ISO codes for symmetric gears to justify the results of the finite element method pertaining to this study.     

刀具预调仪概述

针对机光电一体化产品刀具预调测量仪,介绍了该仪器的作用、结构、工作原理,并根据目前国内外刀具预调仪的使用情况,总结了其外形、结构、软件、控制系统上存在的问题,为刀具预调仪的研发方向提供了参考。