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关键词： 磁流变   电梯   辅助安全传动装置   离合器   制动器  

摘要： 电梯是建筑中用于垂直输送人员或货物的交通运输工具。属于特种设备,在使用过程中必须保证安全性与可靠性,同时也需要满足乘坐舒适性、能耗、噪声等多方面的要求。为实现电梯高可靠性和高安全性的启动、制停运行性能,提出了基于磁流变技术的传递力矩与产生制动力的的电梯辅助安全传动装置设计理念。内容包括:电梯磁流变离合传动装置、电梯磁流变制动装置的基本结构,分析了其工作原理;针对电梯信号特征剖析了其控制方式,为电梯传动系统的安全可靠性提供了双重功能保护。磁流变技术发展为电梯安全技术创新提供新的思路,同时也为磁流变传动机构的应用与研究提供了理论基础。

关键词： 自动变速器   技术讲座   国产轿车   维修   专用工具   离合器   输入轴   驱动轴  

摘要： 调整离合器K1的步骤： 第一步，取下外侧驱动轴（输入轴2）上的卡簧，放入调整专用工具T10374，并用手转动确保其接合牢靠。

关键词： 离合器   从动盘总成   关键零件   表面处理  

摘要： 目前,汽车离合器从动盘总成产品中的从动盘、减振盘、盘毂、压紧片和垫片等关键金属零件的表面较多采用磷化生产工艺,工艺技术落后,产品外观不好看,不同批次零件表面色差大；工件尺寸受磷化时间影响,精度难以控制,质量不稳定,且磷化工艺使用的硫酸污染程度高；部分零件采用镀锌、镀铬、镀镍等电镀工艺,其价格昂贵,对环境的污染大,已不适应企业发展的需要。

关键词： 车辆工程   离合器   热弹性不稳定性   临界速度   结构参数   有限元法  

摘要： 应用热弹性不稳定性(TEI)理论研究离合器接合过程中的局部高温区产生的原因与发展规律。通过有限元建模的方法建立了离合器接合过程三维有限元模型,并求解不同频率扰动对应的增长系数。研究发现:减小离合器半径尺寸、增大摩擦片厚度可以提高系统热弹性稳定性;离合器内外径比值小于0.6时,减小内外径比值有利于提高稳定性;离合器对偶片半厚度小于2mm时,减小对偶片厚度有利于提高稳定性。

关键词： CLUTCHES (Machinery)   HYDRAULIC control   TAPS & dies   HYDRAULIC engineering  

摘要： The article offers information on clutches that were used 25 years ago as of August 2014 that engage and disengage power transmission in hydraulic systems. Topics discussed include utility of clutches for power system loading and unloading, the views of mechanical engineer Joseph A. Montaine on the efficiency of clutches, and the role of clutches in reducing system cost by tapping into a pressurized hydraulic system.

关键词： Little Auk   Alle alle   brood enlargement   incubation   single-egg layer   INCUBATION CAPACITY   SIZE   GROWTH   DOVEKIE   SUCCESS   CHICKS   MURRES   COSTS   RATES   FIELD  

摘要： Initial reproductive investments in birds are energy-demanding. Amount of energy allocated to egg production and incubation may have an important role in determining parental fitness and evolution of clutch size. Here, we investigated whether the Little Auk (Alle alle (L., 1758)), a small alcid with one-egg clutch but two brood patches (probably remnant of the original two-egg clutch), is capable of incubating two eggs and rearing two chicks. We performed an experiment with removing the egg from 20 nests and transferring it to 20 experimental nests (EN). In 25% of EN, both eggs failed to hatch; in 75% of EN, only one egg hatched successfully. Hatching success in EN was 2.5 times lower than in control nests (CN). In EN, chicks hatched only from eggs warmed during >90% of inspections. Owing to the prolonged incubation, the chicks in EN hatched 2 days later than in CN. However, due to the shorter period spent in the nest in EN, fledging dates in both types of nests were similar. The similar body mass and survival of chicks from EN and CN suggest that these traits were influenced mainly by the rearing conditions. Our study emphasize the importance of the incubation phase as a constraint on clutch size.

关键词： Blue copper sites   Pseudoazurin   Type 1 copper   275 GHz EPR   Absorption spectrum   Plastocyanin   ELECTRON-PARAMAGNETIC-RESONANCE   ATOMIC-RESOLUTION STRUCTURES   ALCALIGENES-FAECALIS S-6   NITRITE REDUCTASE   CRYSTAL-STRUCTURE   ACHROMOBACTER-CYCLOCLASTES   SPECTROSCOPIC PROPERTIES   CONTINUOUS-WAVE   SINGLE-CRYSTAL   PI-INTERACTION  

摘要： We report on a high-frequency electron-paramagnetic-resonance study of the type 1 copper site of pseudoazurin. The spectra fully resolve the contribution of a nearly axial spectrum besides the rhombic spectrum, which unequivocally proves the existence of two conformations of the copper site. Pseudoazurins have been considered from Achromobacter cycloclastes including eight mutants and from Alcaligenes faecalis. The two conformations are virtually the same for all pseudoazurins, but the rhombic/axial population varies largely, between 91/9 and 33/67. These observations are discussed in relation to optical absorption spectra and X-ray diffraction structures. A similar observation for fern plastocyanin from Dryopteris crassirhizoma suggests that dual conformations of type 1 copper sites are more common. (C) 2014 Elsevier Inc. All rights reserved.

关键词： Dual clutch transmission   Clutch torque   Output shaft torque   Torque observer   Estimation   Adaptation   ENGAGEMENT   DESIGN  

摘要： The purpose of the proposed work centers on the unprecedented task of accurately estimating the torque transmitted through each clutch of the dual clutch transmission. This is to possibly improve the clutch control performance during vehicle launch and gearshifts and to elongate the clutch life. Such goal is attained by only using the measurements and data that are already available in current production vehicles. The suggested estimator requires the speed measurements of engine, input shafts, and wheels, and nominal engine torque information obtained as a function of driver input and engine speed. By synthesizing the estimations obtained by shaft model-based observer, unknown input observers, and adaptive output torque observer, the novel algorithm to estimate the torque of each clutch separately is developed. Stability of the entire combined observer system is analyzed as well. In the process of developing the transfer shaft model-based observer, an original approach for the driveline modeling is proposed. The driveline modeling procedures include compliance model of each transfer shafts with the convenient methods to express the clutch torque without having to use complex clutch friction models, and the developed model is compared with the actual experiment data to validate its accuracy. The effectiveness of the individual clutch torque estimator is demonstrated both through simulations using SimDriveline, and tests on an actual vehicle equipped with a dual clutch transmission. (C) 2014 Elsevier Ltd. All rights reserved.

关键词： 双离合器自动变速器   干式双离合器   执行机构   优化  

摘要： 针对干式双离合器自动变速器其离合器磨损后对压盘作用力的影响,建立DCT系统动力学模型,膜片弹簧变形模型。基于提前输出支点增加量,研究了不同比例因子下对磨损后离合器压盘压力的影响,在Matlab/Simulink平台上进行仿真优化。