浅谈盘式制动器的工作原理及在重型载货汽车上的应用

制动器是汽车制动系统的主要组成部分，是汽车行驶安全性的重要部件之一。作为一种新型的制动部件，盘式制动器与传统的鼓式制动器比较，具有散热快、重量轻、构造简单、调整方便、制动效果稳定、热稳定性好、高负载时耐高温性能好等优势。随着我国汽车货运、物流的迅速崛起和壮大，重型载货汽车对刺动系统的性能要求越来越高，盘式制动器正越来越广泛地应用于重型载货汽车上。     

汽车制动钳密封性能检测的研究

汽车已成为人们日常生活及工作不可或缺的交通工具之一,在这样一个大环境下,保障汽车的行车安全,就显得尤为必要了。在汽车各部件中,其制动器是其中最为核心的一个工件之一,汽车制动器性能的优劣,对于保障汽车的稳定、安全及延长汽车使用寿命等,起着决定性作用,而在汽车制动器中,其制动钳又是其中最为关键的部件,关于制动钳,其性能通常以其密封性的高低来衡量,若汽车制动钳密封性能不佳,其将导致制动器发生渗漏情况,引发汽车制动效果下降,甚至引发交通事故,因此加大对汽车制动钳密封性能检测的相关研究,有着积极意义。该文将就盘式制动器的工作原理进行分析,在此基础上,对汽车制动钳密封性能检测系统的原理进行详细地探讨。     

制动器实验台的控制方法分析

制动系统是汽车的重要系统,为了检测制动器的综合性能,需要进行大量路试,但是在设计阶段无法路试。而传统的汽车电惯量是制动试验系统采用机械惯量盘模拟汽车运动惯量,这种系统体积大、惯量调整困难、制动化程度不高。针对这些问题,本文采用制动器试验台的控制方法分析并检测制动器的综合性能。首先,本文建立基本的常微分模型来解决电动机驱动电流的问题,其次,是根据已知附表的数据,分别对转速和扭矩与对应的时间应用MATLAB软件拟合出两个函数进而建立了能量差微分模型。     

推广之窗

机械类WTY储能弹簧制动技术及装置编号：T２０１０６７该装置是汽车气压应急制动装置，具有行车制动、驻车制动和应急制动三种功能，适用于各类气压制动的车辆。该装置集三种制动功能于一体，将原来汽车行车制动、驻车制动、应急制动和防抱死的几套装置，变为一个系统－WTY储能弹簧制动装置（停易制动器）。该技术的主要创新在于变制动系统的常开状态为常闭状态，变静态应急制动为兼有静态和动态应急制动，创造了柔性制动理论，防止制动时出现车轮抱死、侧滑、甩尾现象，使行车更加安全，制动更加可靠、稳定。该装置变制动器的常开状态为…     

基于磁流变效应的汽车ABS制动器性能研究

为了解决汽车传统摩擦式制动器存在的缺陷,并为汽车自动驾驶等主动控制提供更多参考,利用磁流变液体在施加磁场时会发生磁流变效应的特性,设计一款前轮磁流变制动器,推导出制动力矩公式,并将模糊控制和滑模变结构控制有效结合,设计汽车ABS模糊滑模变结构控制器。利用Simulink软件对基于磁流变效应的汽车ABS制动器进行建模仿真,得出滑移率、车速-轮速、制动力矩和制动距离仿真曲线。结果表明,通过合理控制施加在制动器磁流变液体上的磁场强度,可较好实现汽车ABS制动要求。     

汽车轮毂智能冷却系统设计

正汽车制动性能事关人身安全,车辆制动系统在车辆的安全方面至关重要,如何提升汽车制动性能一直都是汽车行业的重要研究课题。目前公路客车多数采用前盘后鼓式制动,制动时通过制动鼓和摩擦片相互摩擦产生阻力来制动,在此过程机械能转化成热能。当汽车在山路下山行驶时,常处于连续长时间制动状态,受鼓式制动器结构影响,散热能力差,制动过程中会聚集大量热量,摩擦片和轮毂在高温影响下发生极为复杂的变形,     

汽车电子机械制动器的效能分析

为了分析电子机械制动器（electmmechanical bloking，简称EMB）的制动效能，建立了电子机械制动器的数学模型和在水平路面上汽车制动时整车动力学模型，运用MATLAB／SIMULINK仿真软件对电子机械制动器和液压制动器（hydmulic braking简称HB）的制动性能进行了比较．结果表明：电子机械制动器的制动效能明显优于传统的液压制动器，为电子机械制动器工程开发提供了理论依据.     

浅析汽车制动系统故障诊断及维修

在分析了汽车制动故障诊断及维修对确保汽车行车安全的重要性和必要性后，结合自我多年工作经验，对引起汽车制动故障的主要原因进行了归纳总结。最后详细介绍了制动失效或不灵、制动跑偏与制动侧滑、驻车制动器失灵等常见的汽车制动系统故障的故障现象、故障原因、以及故障诊断与排除方法。     

基于复模态灵敏度分析的制动尖叫控制研究

制动器摩擦导致的制动尖叫对汽车的乘坐舒适性有着重要影响,是工业界和学术界面临的重点和难点问题。建立制动器复模态分析模型进行制动器不稳定模态特征分析,并进行系统模态的灵敏度分析,确定子结构模态参数对系统不稳定模态实部和虚部的影响,明确了制动器系统不稳定模态及尖叫发生的关键部件几何参数,为面向制动尖叫抑制的制动器子结构优化设计提供依据。优化方案的复模态仿真及系统尖叫特性试验结果分析表明,基于模态灵敏度分析得到的制动盘V槽深度优化设计方案能有效抑制盘式制动器尖叫问题。     

动漫创造首次列入合肥科研课题

6月9日，安徽神剑科技股份有限公司与合肥工业大学科教开发部签署协议，联合成立“合肥工业大学——安徽神剑科技股份有限公司汽车制动系统研发中心”，合作开发具有自主知识产权的汽车制动器产品。该“研发中心”的成立，将填补华东地区专业研发、生产汽车盘式制动器的空白。     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

An Index mechanism for multi-scale view in spatial databases

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.     

A computer generator for randomly layered structures

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

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

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。     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

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     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.