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1.
刘勇 《当代地方科技》2011,(16):123-123
在选择和使用履带起重机力矩限制器的传感器时要考虑安装方式、安全系数、信号类型、接线方式和成本等几个方面,下面分力传感器和角度传感器两方面介绍。  相似文献   

2.
起重机力矩保护装置的设计在中国虽然已经有一段历史了,但传统的起重机力矩保护装置还有很多的问题与限制,本文设计的在线监控系统由数据采集模块和监控主机两个部分组成.整个系统采用中文显示,操作方便,实现了诸多工作参数的数字化集中显示与控制,提高了起重机的自动化程度和安全操作性.  相似文献   

3.
本文介绍了以STM32F103为核心芯片构成的超载限制器,用来控制起重机的安全运行。该系统具有保护、报警、实时记录并显示多个工作参数的功能,是一种可靠的起重机安全保护装置。  相似文献   

4.
单片机力矩限制器的研究   总被引:1,自引:0,他引:1  
用MCS-96系列单片机中的8098作为主控芯片,用软件对起重力矩实现控制并自动报警和制动,成功地制成了单片机力矩限制器。经在新开发的百吨液压起重机上试用,表明具有良好的技术性能和经济效益。  相似文献   

5.
张芸 《科技信息》2009,(9):82-82
载荷试验是检验起重机械产品质量及安全性能的综合性的重要指标,通过载荷试验不仅可以检测出起重机金属结构的变形情况,如桥式起重机的挠度值等,还可以检测出起重机安全装置的有效情况,如超载限制器,塔式起重机在额定载荷状态下的力矩限制器的动作保护情况等。总之,载荷试验对检查起重机及其部件的结构承载能力,起重机的焊接、裂纹情况,永久性变形,联接松动情况,安全装置有效性及起重机性能与安全有影响的损坏情况,都是极为重要的。  相似文献   

6.
内嵌扭矩传感器的紧凑型一体化关节可增加机器人的负载质量比,提高力控安全性,更适用于服务行业。通过对轻型协作机器人关节的研究,提出了机器人关节系统整体设计方案。基于关节设计参数,研究关节系统工况负载下的可靠性。对关节扭矩特性进行分析,设计了17型号关节扭矩传感器本体,并采用有限元仿真方法,验证了应变片安装位置的合理性。研制了放大与低通滤波电路系统,并对传感器进行实验分析标定,拟合扭矩电压特性曲线,得到线性度、灵敏度、迟滞和零漂参数。最后对研制的关节整机进行负载测试,并应用于五自由度碳纤维轻型机械臂系统。结果表明:紧凑型内嵌扭矩传感器机器人关节质量轻、负载能力高,扭矩传感器具有较高的精度和灵敏度。  相似文献   

7.
吊车是海上采油平台的重要设备之一,当吊机超载作业产生过大应力,可能使钢丝绳拉断、传动机构损坏、马达及液压缸憋压或者下滑,制动失效,甚至造成臂架折断、回转轴承解体,严重的可能导致整个起重机倾覆。在海上平台大多数起重机上安装力矩限制器和超载保护装置,针对平台电动吊车力矩仪因使用时间较长存在的重量数值漂移、显示背灯故障等问题进行分析,并对力矩仪进行了换型改造。  相似文献   

8.
开发了1种适用于各种型号带式输送机托辊的计算机监测系统。研究了托辊工况监测系统动态参数模型与计算方法,这种方法是基于理论力学中"转动惯量法"的原理,从力矩平衡的角度出发,建立起被测参数的数学模型。论述了监测系统的组成及工作原理,进行了系统硬件原理电路的设计和软件系统结构及数据处理应用程序的设计。分析了系统的测量精度和可靠性,由此得出该系统的设计能够满足使用要求。  相似文献   

9.
本文主要讨论了起重量限制器的原理和特点及起重量限制器在电动单梁起重机上的安装形式,结合起重机检验中发现的问题,对起重量限制器的相关问题的解决进行探讨。  相似文献   

10.
选取了QY-8型液压起重机的伸缩臂液压系统为研究对象,采用AMESim软件建立了液压回路仿真模型,通过模拟不同工况下的负载,对液压系统工作过程进行了动态仿真。分析不同的动态特性曲线发现,动态仿真结果与理论预期效果相符合,且仿真过程平稳,为更大载荷汽车起重机液压系统设计和参数优化提供了依据。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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