共查询到20条相似文献,搜索用时 109 毫秒
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旋阀机构是保证中速柴油机进、排气阀正常工作的重要装置,本文介绍的改进型旋阀机构不仅保证气阀在开启过程中能不断传动,而且使气 在落座过程中亦能保持这种传动,从而进一步改善气阀的工作条件,延长气阀的使用寿命。 相似文献
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往复式压缩机排气阀阀片的改进 总被引:1,自引:0,他引:1
往复式压缩机排气阀阀片损坏频繁,尤其是一级排气阀每月平均损坏1.2次。针对气阀工作面与阀片表面有转动磨痕的现象,对阀片进行了两次技术改进,效果明显。 相似文献
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为了有效提升多功能体育训练器的全局性能,对其重要部件关节旋转器旋转角度进行合理优化是十分必要的。由此,提出一种基于动力学的关节旋转器旋转角度动态优化方法。多功能体育训练器是由关节旋转器、圆形中央框架、防护设备及电机传动设备组成的,同时探究其内在原理与训练优势。建立直角坐标系准确展现人体和关节旋转器之间的关系,获取空间某个物体方位值,完成关节旋转器运动控制。结合动力学原理,研究上肢进行运动旋转时形成的动力方程,构建关节旋转器旋转角度推导模型,明确其旋转角度最优取值范围。仿真结果证明,所提方法可以大幅减少关节旋转器摩擦系数,让关节旋转器使用状态更为灵活,达到多功能体育训练器稳定安全的使用目标。 相似文献
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Ortho-planar linear-motion springs 总被引:1,自引:0,他引:1
This paper presents an ortho-planar spring design that operates by raising or lowering its platform relative to the base with no rotation. The compact nature of the design, and its non-rotating motion, eliminates the problem of rotation against adjoining surfaces and is less sensitive to variation in assemblies than many current compact springs. Nomenclature is presented to identify different configurations, mathematical equations are provided that accurately model the force–deflection relationships, and a pneumatic valve positioner application is demonstrated. 相似文献
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利用神经网络对泵机组进行了故障诊断,探讨了故障诊断的神经网络方法和专家系统方法的联系和区别。该分析方法为转子临界速度的计算提供了比较完善的方法。 相似文献
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回转式伺服阀作为直动式电液伺服阀的一个分类,利用阀芯(或阀板)相对阀体作旋转运动来实现油路的开闭、换向和流量调节。相对于滑阀,转阀具有结构简单紧凑、流量分辨率高、无加速度零漂、抗污染能力强及维护方便的特点。回转电液伺服阀作为电液伺服控制系统的控制元件,具有其自身的特点和优势,尤其是单级、高频响、大流量阀的研究开发,已成为电液伺服阀发展的一个重要方向,前景广阔。该文对伺服转阀进行了归类并针对国内外液压伺服转阀的研发现状、结构特点、功能的具体实现及设计原则进行了详细的分析和梳理。最后,结合现有的伺服转阀探讨了一种满足更高要求的新型结构形式。该文将为回转式电液伺服阀的研发及应用工作提供参考。 相似文献
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文章从流道结构分析了伺服阀阀芯在工作时旋转的原因,并结合目前市场上主流型号的伺服阀,归纳总结了其防止阀芯转动的设计方法,为伺服阀设计提供了指导。 相似文献
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Tokarev A Aprelev A Zakharov MN Korneva G Gogotsi Y Kornev KG 《The Review of scientific instruments》2012,83(6):065110
We report on the development of a multifunctional magnetic rotator that has been built and used during the last five years by two groups from Clemson and Drexel Universities studying the rheological properties of microdroplets. This magnetic rotator allows one to generate rotating magnetic fields in a broad frequency band, from hertz to tens kilohertz. We illustrate its flexibility and robustness by conducting the rheological studies of simple and polymeric fluids at the nano and microscale. First we reproduce a temperature-dependent viscosity of a synthetic oil used as a viscosity standard. Magnetic rotational spectroscopy with suspended nickel nanorods was used in these studies. As a second example, we converted the magnetic rotator into a pump with precise controlled flow modulation. Using multiwalled carbon nanotubes, we were able to estimate the shear modulus of sickle hemoglobin polymer. We believe that this multifunctional magnetic system will be useful not only for micro and nanorheological studies, but it will find much broader applications requiring remote controlled manipulation of micro and nanoobjects. 相似文献
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A 2D high-frequency rotary directional control valve with a spool having two degrees of freedom for axial linear motion and circumferential rotation is proposed in this paper. The axial linear motion decides the maximum orifice area, and the circumferential rotation lets the orifice area change continuously. One of the known elements impacting valve function is the flow force. This paper systematically analyzes the steady and transient flow torques subjected to the valve through theoretical analysis, AMESim-Fluent joint simulation and experimental tests. The results show that: under a single variable, the flow torques of the 2D high-frequency rotary directional control valve initially increase and then decrease like the sinusoid curve with the rotation of the spool and reach the maximum when the orifice opening is 1/2, and the flow torques are always in the direction of orifice closing and want to close the orifice. When the orifice area increases, the flow torques are the resistance, preventing the spool from opening; when the orifice area decreases, the flow torques are the power, pushing the spool to close. The steady flow torques are proportional to the pressure drop. The direction of the transient flow torque is independent of the relative position of the spool groove and sleeve window, which proportional to the square root of the pressure drop, orifice area and rotational speed. The flow torques are so important in the control of valve and can not be negligible. 相似文献