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关键词： 混动专用变速箱   DHT   离合器   故障处理  

摘要： 作为一种全新设计的变速箱,混动专用变速箱DHT(Dedicated Hybrid Transmission)具有结构紧凑、模式多样、综合性能优异等优点。基于典型的串并混联单档DHT,结合其动力耦合装置离合器功能,设计了一种离合器故障处理策略并进行了实车验证。测试结果表明,所设计的故障处理策略能保证车辆在不停车条件下仍然安全跛行回家。

关键词： 离合器   传动系统   扭转特性   冲击问题  

摘要： 某12 m大型客车3挡加油门和收油门工况存在明显的冲击问题,考虑离合器从动盘扭转特性、齿轮时变刚度、齿轮侧隙和主要部分花键侧隙,建立AMESim的传动系统仿真模型,发动机和变速器一轴转动波动仿真结果与试验测试结果表现一致,验证了仿真模型的有效性。进而分析了离合器扭转特性对传动系冲击问题的影响,并进行了试验验证。结果表明:预减振弹簧部分工作角度对冲击问题存在一定程度的影响,为传动系统匹配及冲击问题提供了参考。

关键词： 减定径机组   离合器   西门子S7-400 PLC   S120变频器   故障处理  

摘要： 介绍了高线厂减定径机组主齿轮箱离合器控制系统的组成及工作原理,阐述其基本控制流程,对生产过程中出现的典型故障进行分析和处理。通过对离合器运行状态增加实时监控及相关连锁条件等优化措施,把故障从事后抢修向预测维修转变,确保减定径机组安全稳定运行。

关键词： 软盒包装机   转向机构   行星轮系   离合器  

摘要： 目的:解决YB25型软盒包装机烟包转向机构故障率高、易造成烟包损伤等问题。方法:通过对烟包转向机构各零部件磨损情况分析,找出机构设计缺陷,设计了性能更稳定的三点式对称偏心结构行星轮系,并配合改进了专用离合器以保证其过载保护。结果:改进后转向机构故障率降低,单次维修时间减少54 min,设备噪音减小46 dB,半年内相关质量缺陷烟包减少275包,质量隐患降低。结论:改进后烟包转向机构实现了高效率运转,有效地解决了YB25型软盒烟包转向机构的高故障率问题。

关键词： vibrations   flexible torsion clutch   STFT   order analysis   Campbell diagram  

摘要： The paper presents how an important aspect of introducing new machines, especially in the mining industry, is testing a prototype under laboratory conditions. For this purpose, advanced methods of analyzing the vibrations of a drive system equipped with an innovative prototype of a flexible torsion clutch are presented. The main goal is to present a comprehensive method for analyzing vibration signals in various dimensions of the signal analysis. As a result of this approach, it can be seen how much important information about the tested clutch can be obtained by using various analysis methods in terms of time-frequency distributions or order analysis. To emphasize the differences in the functioning of the tested clutch and the possibility of monitoring these differences on the basis of the observation of residual processes, such as vibrations, the results for the flexible and locked clutch are compared.

关键词： circRNA_0001971   FNDC3B   miR-186-5p   oral squamous cell carcinoma  

摘要： Background Circular RNAs (circRNAs) are closely associated with the progression of oral squamous cell carcinoma (OSCC). circRNA_0001971 has been proved to accelerate the OSCC development. Here, we aim to identify the new molecular mechanism of hsa_circRNA_0001971 (circRNA_0001971) in OSCC. Methods The levels of circRNA_0001971, miR-186-5p, and fibronectin type III domain containing 3B (FNDC3B) in tissues and cells were verified by qRT-PCR or Western blotting. The interaction between circRNA_0001971, miR-186-5p, and FNDC3B was identified by bioinformatics analysis, luciferase assay, and RIP assay. The effect of circRNA_0001971/miR-186-5p/FNDC3B axis on OSCC cell proliferation, migration, and invasion by cell functional experiments including CCK8, wound healing, and transwell assays. Results Our study displayed that circRNA_0001971 and FNDC3B were elevated in OSCC, whereas miR-186-5p was declined in OSCC. Silencing circRNA_0001971 attenuated the malignancy of OSCC cells by suppressing proliferation, migration, and invasion. In OSCC cells, circRNA_0001971 sponged miR-186-5p to enhance FNDC3B. Due to the interaction between circRNA_0001971, miR-186-5p, and FNDC3B, FNDC3B overexpression relieved the negative function of silencing circRNA_0001971 in OSCC cells. Conclusion Overall, our study discovered that circRNA_0001971 was a tumor promoter in OSCC progression by targeting miR-186-5p/FNDC3B axis.

关键词： 齿轮传动   风扇发动机   可拆卸转子   总体结构设计   高涵道比  

摘要： 本文简要介绍了齿轮传动风扇发动机(GTF)的总体结构设计要求、发展历程,重点分析了两型现代先进GTF发动机(PW8000和PW1000G)的总体结构设计特点,对其在支承方案、支承结构和转子结构方面的设计思路进行了深入剖析和评估,提出了对于GTF涡扇发动机结构设计中的关键技术及其解决途径.

关键词： 离合器KP   测试方案  

摘要： 在变速箱中,离合器需要进行动力的传递和断开,根据离合器结合过程的特征,使得动力从不传递到开始传递的离合器压力点为离合器KissPoint(KP)点。文章主要对离合器KP参数测试方案进行研究,提出了几种可行的测试方法,对实际测试过程具有指导意义,可以帮助测试人员以及标定开发人员获得较为准确的KP点数据,使得后续离合器控制更加精确高效。

关键词： 自调式膜片弹簧离合器   优化分析   寿命评估   磨损使用寿命里程  

摘要： 分别对自调式膜片弹簧离合器的基本参数、膜片弹簧和力感应弹簧进行优化分析,在此基础上对其寿命进行评估。优化结果表明:基本参数设计比原始结构尺寸设计更紧凑;膜片弹簧的尺寸参数更加合理,压紧力和踏板力大幅度减少;力感应弹簧零刚度载荷值明显的减少。寿命评估结果表明:汽车在城市或近郊路面行驶时,离合器磨损使用寿命里程约为32000 km,在道路坡度较大及干砂里面行驶,其磨损使用寿命里程约为13010 km。极限路况下,在滚动阻力系数较小的路面行驶,离合器的磨损使用寿命里程较长,反则磨损寿命里程较短。本文研究结果可为自调式膜片弹簧离合器的结构优化和寿命评估的分析提供理论依据。

关键词： Torque   Optimization   Dynamics (Mechanics)   Torque converters   Inertia (Mechanics)   Engines  

摘要： The paper presents a detailed numerical and algebraic analysis of potential for improving the step ratio automatic transmission (AT) upshift performance by means of modulating the off-going clutch during the inertia phase. The numerical analysis is based on Pareto optimal frontiers obtained by using the previously developed methods for AT shift control trajectory optimization and piecewise-linear control profile parameter optimization, where the control objectives include minimization of shift time, vehicle root mean square jerk, and dissipated clutch energy. The analysis concerns the following control scenarios related to inertia phase: (1) oncoming clutch control only, (2) combined action of oncoming and off-going clutch, (3) oncoming clutch control extended with engine torque reduction control, and (4) combining all three control actions. The numerical results relate to an advanced 10-speed AT and various single-step and double-step upshifts, with emphasis on 1-3 shift. The numerical analysis results are proven algebraically based on a simplified AT model represented in bond graph form. The presented analysis shows that the off-going clutch can reduce either shift time or root mean square jerk index by introducing power recirculation via the two clutches, which is in turn paid for by certain increase of AT energy loss.