液体动压浮环式推力轴承的静特性及参数

建立了浮环式推力轴承的数学模型，分析了轴承的承载能力、摩擦功耗、温升、浮环－转子的转速比等静态特性及结构参数．实验验证了理论计算的正确性．     

向心推力轴承轴向载荷的计算

本文介绍向心椎力轴承轴向载荷的计算公式的推导原理。     

弹性金属塑料瓦推力轴承试验台的研制

以弹性金属塑料瓦推力轴承为研究对象,设计推力轴承试验台,研究弹性金属塑料瓦与普通金属轴瓦的性能区别,并为研究弹性金属塑料瓦推力轴承的起动过程作试验准备.     

弹性金属塑料瓦推力轴承试验台的研制

以弹性金属塑料瓦推力轴承为研究对象，设计推力轴承试验台，研究弹性金属塑料瓦与普通金属轴瓦的性能区别，并为研究弹性金属塑料瓦推力轴承的起动过程作试验准备．     

推力轴承外罩冲孔打字复合模的设计

文章介绍了模具结构、工作过程及其设计与加工注意事项。生产实践证明:模具结构紧凑,产品质量良好,满足生产要求。     

浅析汽车的力学特性

汽车是人们所熟悉的交通工具,也是物理学力学部份教材和练习中经常讨论到的实例。但是,有关汽车的某些力学特性,某些人们往往先入为主,建立一些模糊的、甚至是错误的概念。因此,对其作一些分析讨论,是有现实意义的。 一、车轮所受摩擦力分析 在物理学教材有关功能原理的章节中,讨论到汽车时,曾指出摩擦力是耗散力,摩擦力的方向和运动物体的运动方向相反,所以摩擦力所作的功是负的。 日常生活中,人们认为汽车之所以能前进是因为有发动机的牵引。但是,从物理学的角度看,这种解释是不够确切的。因为大家知道不论内力有多大,是不能改变物体的运动状态的。要使汽车由静止起动,必须使汽车受到外力的作用,即必须要有汽车以外物体的作用。     

径向磁轴承的力学特性

This paper is based on the example of a radial magnetic bearing possessed of eight-pole, and derives the calculation formulas of static and dynamic mechanical characteristics of the bearing, in which the shape and curvature of surface, eccentricity and tilt of the journal are taken into account. Variations of the static and dynamic characteristics of the radial magnetic bearing versus static tilt parameters of journal are discussed. The outcomes show that the static tilt of the journal has influence on the mechanical characteristics of radial magnetic bearing, and change the static load capacity between two radial magnetic bearings and exert coupling effect between them. To study the dynamics of a practical rotor-magnetic bearing system, at least six stiffness coefficients in each radial magnetic bearing must be considered in ideal case, and twelve stiffness coefficients must be considered in general case of tilting journal. Such a find can be used for the coupled electromechanical dynamics analysis of rotor system equipped with magnetic bearings.     

金属波纹管力学特性的计算

金属波纹管是端面密封装置上的一个重要元件。与密封圈相比,它的密封性绝对可靠,能耐高温,很有推广和发展的前途。为此,我们必须了解:波纹管对密封端面所产生的弹性预紧力是多少?对密封端面所产生的载荷自紧力是多少?在密封介质压力的作用下,波纹管的金属膜片将发生变形,这一变形又会对载荷自紧力产生多大的影响?下面将详细讨论这三个问题。     

气体和液体的力学特性

空气是最常见的一种气体物质，水是最常见的一种液体物质．在一个标准大气压OC的条件下，空气的密度为1．29千克／米’，水的密度为1．0X10’千克／米‘，水的密度是空气密度的775．2倍．虽然两者密度相差如此之大，但是，它们都具有流动性．正因为气体物质和液体物质都能流动，所以人们常把气体物质和液体物质统称为流体．正是这种流动性，使得一定质量的气体或液体都没有固定的外形，它们的形状随着盛装它们的容器的内空形状而定．但是，一定质量的液体具有一定的体积．比如，1干克水的体积是1升，这个体积大小几乎不随外界压强变化而改…     

双封油边斜——平面固定瓦推力轴承的最佳斜面比

对在斜—平面扇形固定瓦推力轴承瓦面的内、外径上同时设置封油边时,基本参数斜面比对轴承性能的影响进行分析和计算,提出这种结构的最佳斜面比.     

Mechanical Characteristics of Radial Magnetic Bearing

1 IntroductionThe great majority of docUments about magneticbearings dealt only with the characteristics when thejournal was concentric with the radial magnetic bearing inthe past, and few research involved the ones when thejournal was eccotic with the radial magnetic bearing.For example, the bulk of documents suPPosed thecomponents Fx and F. of magnetic force depended onlyon the cUrred in x and y direchons respeGtively, bac theair gap thickness and the curvatUre of suiface shape werenot co…     

Reaction thrust characteristics of high-pressure submerged water jet of cylinder nozzles

The shapes and geometrical parameters of nozzles are key factors for fluidics. The relationship among the reaction thrust, flow rate pressure, diameter do and length L of a cylinder nozzle is analyzed theoretically. The simulation of the flow field characteristics was conducted via the FLUENT computational fluid dynamics package. Effects of the inlet conditions and the nozzle dimensions on the reaction thrust of a water jet were addressed particularly. The reaction thrust experiments were performed on a custom-designed test apparatus. The experimental results reveal that a） the nozzle diameter and the inlet conditions exert great influence on the water jet reaction thrust; and b） for L≤4d0, where the nozzle is treated as a thin plate-orifice, the reaction thrust is independent of nozzle length; for L〉4d0, where the nozzle is treated as a long orifice, the reaction thrust can reach maximum under the condition of a certain flow rate. These findings lay a theoretical foundation for the design of nozzles and have significant value, especially for the future development of high-oressure water-let orooulsion technology.     

高速角接触陶瓷球轴承动态特性研究

根据滚动轴承的分析理论建立了轴承的动态数学模型并通过Hook-Jeeves的优化方法求解，研究了高速角接触陶瓷球轴承的动态特性，并与传统的钢轴承作了对比．结果表明：与低转速工况时相比，高转速时轴承的动态性能不仅受预加载荷的影响，而且在更大程度上与转速和滚珠材料特性有关：随转速的升高，轴承的轴向刚度与径向刚度均发生显变化，变化趋势为先下降后上升；在高速状态下，与传统钢轴承相比，陶瓷球轴承的接触应力及变形明显降低、接触角变化较小、轴向与径向刚度变化程度相对较低、动态特性相对稳定，从而具有传统钢球轴承无可比拟的优越性．     

调心球轴承动态特性参数分析

基于Jones-Harris方法建立了调心球轴承的动力学模型,应用Newton-Raphson方法对轴承动力学方程组进行了求解,开发了相应的计算程序.完成了该轴承的离心力、陀螺力矩、接触载荷、接触角、径向变形与径向刚度等动态特性参数分析.分析结果表明：转速与载荷是影响接触角大小与接触载荷分布最主要的2个因素;滚子的离心力与陀螺力矩随着转速的上升而增大,在此影响下外圈接触载荷增大而内圈接触载荷减小;受离心力的影响,外圈的接触角减小而内圈的接触角增大,且随着转速的增加,内外圈接触角的差值越来越大;轴承的径向刚度随着转速的上升而下降,而滚道沟曲率系数也对轴承径向刚度有一定程度的影响.     

Experimental study of active magnetic bearing on a 150M3 turbo oxygen gas expander

This paper is concerned with the investigation, experiment and design analyses on the application of active magnetic bearings for a 150M³ turbo oxygen gas expander having 1.16 kg weight and 30 mm diameter rotor, which was supported by two aerostatic bearings formerly. Now, the machine can work steady at a rotation speed of 92,000 r/min, and can be run up to a maximum rotation speed of 104,000 r/min. Project supported by the Science and Technology Development Foundation of Educational and Science Commission of Shanghai (59875054)     

小型推力关节轴承轴圈外球面电解测厚工装设计

针对推力关节轴承内圈外球面镀铬层厚度检测采用电解法,在检测过程中经常因为难以固定工件、电解液的渗漏等因素导致难以测量测量不准确。本文设计专用工装,快速固定工件,准确地测量了镀层厚度。     

用有限元法分析径向磁性联轴器的力矩特性

从电磁场的基本理论出发，建立了径向磁性联轴器的有限元数学模型，利用磁场的周期性条件来压缩求解区域范围，使计算大为简化。分析了环间转角、磁极数、磁环尺寸、磁环间距等因素对联轴器传动力矩的影响，并总结了径向磁性联轴器力矩特性的变化规律。     

Calculating magnetic shielding effectiveness for high-power dc comparator by magnetic circuit method

Magnetic shielding is very important in the design of a high-power dc comparator. This paper addressed the application of magnetic circuit method to calculate the magnetic shielding effectiveness of high-power dc comparators when an external radial magnetic field is added. The mathematical relationship between the magnetic shielding effectiveness and the parameters of the magnetic shielding body were obtained. To verify the validity of the calculation method, we developped a procedure to measure the magnetic shielding effectiveness of the magnetic body by measuring the induction voltage of the detection winding instead of the magnetic intensity at a point in the magnetic shielding body, making the manipulation much easier. The result calculated with the magnetic circuit method turns out to be closer to the measured one compared with that calculated with a conventional algorithm proposed by Ren, suggesting that the magnetic circuit method is an applicable tool for estimating the toroidal cavity magnetic shielding effectiveness of a heavy current comparator when a radial magnetic field is added.     

基于三维磁场的机械伤残控制系统

系统以AT89C52单片机为控制单元,介绍了一种由4个线性霍尔传感器构成三维磁场测量的机械伤残控制系统.将含有磁体的特殊物品佩戴在手腕上,利用系统测量磁体与＂0＂点的距离,间接地检测＂人手＂的位置,以达到保护人体的目的.该系统具有结构新颖、电路简单、控制准确、生产成本低廉和体积小巧等优点,特别适合应用于机械设备的安全控制.     

Reaction thrust of water jet for conical nozzles

Clear knowledge on the reaction thrust of water jet is valuable for better design of water jet propulsion system. In
this paper, theoretical, numerical and experimental studies were carried out to investigate the effects of the nozzle geometry
as well as the inlet conditions on the reaction thrust of water jet. Comparison analyses reveal that the reaction thrust has a
direct proportional relationship with the product of the inlet pressure, the square of flow rate and two-thirds power exponent
of the input power. The results also indicate that the diameter of the cylinder column for the conical nozzle has great influence
on the reaction thrust characteristics. In addition, the best values of the half cone angle and the cylinder column length exist
to make the reaction thrust reach its maximum under the same inlet conditions．