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通过对小型多回转阀门电动装置结构的分析,提出了一种新的传动结构,减小了阀门电动装置的体积和重量,并通过实例验证阀门电动装置采用谐波齿轮传动的可行性,为谐波齿轮传动在阀门电动装置中的应用研究提供了参考。 相似文献
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汪克成 《世界仪表与自动化》2008,12(1):34-36
近年来.随着微电子和控制技术的发展.执行器产品的数字化、智能化、通信化技术也得到了快速发展。执行器产品中气动和电动控制阀是过程控制系统最为广泛使用的现场仪表之一,智能阀门定位器和智能电动执行机构是控制阀智能化和通信化得到实现的关键. 相似文献
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针对传统阀门电动执行器存在控制精度低、稳定性差现象,设计了一种智能阀门电动执行器。其中硬件设计以SAF-XE167FM-72F80L为核心CPU,包含扩展电源供电电路、A/D采样电路、驱动电机电路、看门狗电路、LCD液晶显示电路等。软件设计以滑模控制算法为基础,设计位置环、速度环、电流环三环控制方案,克服阀门控制过程存在的非线性、时变特性。通过改进阀门电动执行器硬件、软件系统,有效避免阀门控制的不稳定因数并完成实验室测试。测试结果表明,该阀门电动执行器可实现对阀门的稳定、快速、精确控制,阀门位置误差率小于2.5%,满足阀门控制要求。 相似文献
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阀门电动装置主传动结构分析天津市阀门公司成套处王桂红,闫仲鸣一、Rotork阀门电动装置1.结构通常多回转阀门电动装置的输出转矩达到300N·m,并且在低速轴(空心轴)上进行手电动切换〔其手电动切换力和手轮力均很大。为此间门电动装置生产厂家都采取了一... 相似文献
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In a recent paper, the Ritz method with simple algebraic polynomials as trial functions was used to obtain an eigenvalue equation for the free vibration of a class of homogeneous solids with cavities. The method presented is here extended to the study of a class of non-homogeneous solids, in which each solid is composed of a number of isotropic layers with different material properties. The Cartesian coordinate system is used to describe the geometry of the solid which is modelled by means of a segment bounded by the yz, zx and xy orthogonal coordinate planes and by two curved surfaces which are defined by fairly general polynomial expressions in the coordinates x, y and z. The surface representing the interface between two material layers in the solid is also described by a polynomial expression in the coordinates x, y and z. In order to demonstrate the accuracy of the approach, natural frequencies are given for both a two- and three-layered spherical shell and for a homogeneous hollow cylinder, as computed using the present approach, and are compared with those obtained using an exact solution. Results are then given for a number of two- and three-layered cylinders and, to demonstrate the versatility of the approach, natural frequencies are given for a five-layered cantilevered beam with a central circular hole as well as for a number of composite solids of more general shape. 相似文献
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通过分析膨胀套在实际使用产生滑移受阻现象、卡死现象原因的实质,并在分析产生问题原因的基础上提出了改进措施即:增加导向机构。 相似文献
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设计了磨粉机快辊轴承座的加工工艺和具体的工装夹具.利用卧式加工中心加工磨粉机快辊轴承座,辅以能够高效快速夹紧的夹具,既可以保证加工精度,又能够提高加工效率. 相似文献
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一种涡旋压缩机径向随变机构的设计 总被引:1,自引:0,他引:1
详细介绍了运用随变原理设计的一种新型径向密封机构的结构特点,工作原理及主要参数的确定方法,该机构可补偿由于涡旋体加工精度不高而造成的功率损失,适用于涡旋压缩机的批量生产。 相似文献
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V. P. Dragunov E. G. Kostsov 《Optoelectronics, Instrumentation and Data Processing》2009,45(3):234-242
Specific features of operation of one- and two-capacitor microelectromechanical converters (MEMC) of energy of mechanical microscopic vibrations into electric energy with a modulated electrode-gap magnitude and with allowance for the mutual influence of electrical and elastic forces are analyzed, and the characteristics of these two devices are compared. The main factors restricting the increase in MEMC power are demonstrated to be the effects of “collapsing” and the condition of conservation of positive rigidity of the system. Expressions for estimating the limiting MEMC parameters are derived. The possibility of electrical energy generation in the presence of “real“ sources of wide-spectrum microscopic vibrations is considered. 相似文献
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针对目前市场对工业设计人才的需求,本文论述了我校在工业设计教育方面的改革措施,着重介绍了我校工业设计教育在软件和硬件方面所进行的一系列的改革。 相似文献
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本文以某些积算和双笔记录仪产品为例说明由于仪表功能设计的不合理或选型不当,影响了仪表的正常使用,制造厂和用户应关注这类问题。 相似文献