一种新型粘度在线检测传感器的设计

介绍了一种基于增量式旋转编码器和悬臂梁式弹性元件的新型旋转式粘度在线检测传感器的设计。该传感器的测量范围为糖膏粘度的范围,它同样适合测量其它大粘度的流体,且检测精度高。本文重点介绍该传感器的结构、测量原理和核心弹性元件的设计,并分析了传感器的误差。用ANSYS有限元分析弹性元件最大挠度和应力,证明设计是合理的。     

FBG式隔水管应变传感器的力学响应特性分析

针对深海隔水管应力监测所设计的光纤布拉格光栅(FBG)应变传感器系统,采用基于有限元方法的软件对传感器在不同载荷模式下的力学响应特性进行了分析,得到了该传感器的应变传递系数。并以仿真结果为依据,对隔水管所受最大应力和弯矩的公式进行了修正。为了获得合适的传感器应变传递系数,通过改变相应参数建立计算了不同的仿真模型,由此分析了弹性元件和固定钢管的弹性模量、长度和外径对它的影响。结果表明:弹性元件长度为调节传感器应变传递系数的最佳参数。     

传感器弹性元件的结构优化设计

给出了以力学分析和机电耦合系统建模理论为基础，以有限元结构分析和优化算法相结合为手段的结构型传感器的计算机辅助优化设计的有效方法。以应变计式引伸计弹性元件的结构优化为例，建立了引伸计弹性元件的力学模型、优化参数模型、优化数学模型，用ANSYS的参数化设计语言编制了分析文件和优化控制文件，经计算获得最优结果。优化结果表明：该方法对传感器的弹性元件结构起到很好的优化作用．可广泛应用于传感器弹性元件的优化设计工程。     

称重传感器弹性元件的结构设计与加工

本文主要阐述了称重传感器技术的发展和现状以及称重传感器弹性元件在设计时应注意的问题。根据应力集中的原则,指出了弹性元件上电阻应变计粘贴的合理位置。分析了弹性元件的制造过程中各个环节对称重传感器性能的影响。对合理设计弹性元件的结构,提高称重传感器整体性能指标和产品质量有充分的参考依据。     

线阵传感器在弹性元件冲击位移测量中的应用

讨论了线阵传感器在舰船动力装置弹性元件冲击位移测量中的应用情况.首先阐述了应用线振传感器进行弹性元件冲击位移测量的原理及测量方法的技术特点.并结合某型舰用弹性联轴器冲击位移测量的实例,验证了该测量方法的可行性,指出了测量方法工程应用前景.研究成果可应用于橡胶隔振器、弹性联轴器、挠性接管等舰用弹性元件冲击位移测量.     

静力触探探头传感器线性度的有限元分析

采用有限元法对静力触探探头传感器的弹性元件进行分析。用此法不仅可以得到弹性元件的应变分布特性,确定应变片的最佳贴片位置,而且可以得到不同载荷下相应节点的应变值。由电压与应变之间的关系式最终可以得到输入载荷与输出电压之间的关系,从而分析出传感器的线性性能。分析结果表明．此传感器的线性度很好,能满足使用要求。     

离心式旋转机械轴向力在线监控装置测力弹性元件的优化设计

文中对离心式旋转机械轴向力在线监控装置作了简单介绍,然后详细介绍了一种离心泵轴向力在线监控装置测力弹性元件的优化设计,为了保证测力传感器的性能,采用有限元法计算了不同结构及尺寸的弹性元件在轴向力F＝39．2kN时的应力、应变及垂直位移的分布,在此基础上优选了最佳的弹性元件结构及最佳的电阻就片贴片位置,显著地提高了测力传感器的灵敏度,并通过实验得到了验证。     

腰形管应变式微压强传感器及其应用

本文介绍应变式微压强传感器的一种新型的弹性元件——腰形管弹性元件。文中论述了腰形管在内压作用下的应变分布规律,并从实验和理论两个方面分析了弹性元件尺寸对传感器灵敏度的影响。当前微压强的测量主要采用水柱压力计和水银柱压力计,由于它们不是电信号输出,因此使用不方便,更不能作为自动控制元件。本文所介绍的采用腰形管作为弹性元件制成的应变式微坛强传感器,它是电信号输出,并且性能稳定,精度高,尺寸小。为了确定弹性元件的形状和尺寸,我们采用有限条元法求解腰形管的应力和应变分布规律,并进行了试验研究,找出了腰形管尺寸对灵敏度影响的规律,从而确定出不同量程下选用的最佳尺寸参数。本文最后介绍了利用该传感器制成的高灵敏度液位传感器和比重计的构造及性能。     

小量程平柝式称重传感器

为使小量程称重传感器具有较高的灵敏度和刚度,其弹性元件多为各种平行梁结构,采用低弹性模量的硬铝合金制造,但外形尺寸较高。本文介绍一种以合金钢为弹性元件材料的新型小量程平板式称重传感器,既具有很低的外形又可以得到较高的灵敏度和刚度。文中重点介绍了平板式称重传感器的结构与特点,受力分析与理论计算,并给出了结构设计与计算实例。     

称重传感器弹性元件的结构设计和材料选择

本文介绍了称重传感器弹性元件的相关知识。简要介绍了弹性元件的设计要求。     

橡胶支承转子不平衡响应试验研究

通过数值计算和实验研究橡胶支承柔性转子系统的不平衡响应。采用基于Timoshenko连续梁理论的有限单元法分析实验转子的临界转速、模态振型和不平衡响应。用Kelvin-Voigt线性粘弹性模型表示橡胶的动态特性。结果表明,使用损耗因子为0.1~0.4的常用橡胶材料可极大地降低转子系统的临界振动响应。3种不平衡量值时,转子一阶临界转速和振幅的试验和数值计算结果吻合较好。受橡胶材料非线性特性的影响,实验和数值计算结果间的偏差随不平衡量的增加而增大。     

基于谐波原理的液体润滑供油方式设计与实现

设计了基于谐波原理的液体润滑供油系统,分析了其基本结构和供油机理。建立了弹性体的变形曲线理论模型和弹性体质点的振动模型;利用有限元软件对弹性体变形进行了计算和分析,对储油腔内润滑油向摩擦表面的供应进行了仿真计算。计算结果表明：工作载荷作用下,弹性体沿径向发生变形,弹性体质点产生振动,质点的振动使储油腔内的润滑油经连通油孔流向摩擦表面,实现了基于谐波原理的润滑油供应,验证了所设计的供油方式的有效性。     

Gas Emission by Permeation Through Elastomeric Seals

Permeation of gas through an elastomeric seal, such as an O-ring or a sheet gasket, depends upon, solubility of the gas in the elastomer and on the diffusion coefficient of the gas in the elastomer. Using values of these parameters measured, on simple test, specimens, emission of gases by permeation through the body of the seal can be predicted by a finite element solution of the axisymmetric Fickian diffusion equation. A computer model has been developed on this basis. Using this, results are presented, to illustrate the effects of the type of gas, type of elastomer, pressure, temperature, and seal installation.     

Tribological behaviour of an elastomer aged in different oils

This paper presents the influence of aging the nitrile rubber, the most popular seal material, in various base fluids on sliding friction and abrasive wear. The lubricants used are synthetic esters, natural esters, different types of mineral base oils, poly-α-olefins and very high viscosity index oils. Friction has been studied for two directions of motion with respect to lay on the elastomer sample by using the SRV Optimol test machine. These findings show that as compared to all other lubricant formulations, ageing the elastomer in polyol ester leads to the maximum reduction of friction coefficient especially in perpendicular sliding to the initial lay on the surface. The abrasive wear studies were carried out by using a two-body abrasive wear tester against dry and lubricated elastomer. It was interesting to note that two-body abrasive wear of elastomeric material was higher during rubbing in presence of the fluids as compared to that in dry condition. Further, aging the elastomer in these base fluids especially in ester base fluids, results in more abrasive wear.     

Testing the elastomer compatibility of aviation turbine oils

This paper covers different parameters influencing the elastomer compatibility of aviation turbine oils. It looks first at the chemistry of rubbers and oils, and then at the chemistry and physics of the interactions of elastomer thermodynamics and oils. The applicability of theory is then demonstrated and judged by means of a practical example.     

The Effect of Elastomer Surface Texturing in Soft Elasto-Hydrodynamic Lubrication

The present study focuses on modeling the effect of elastomer surface texturing in soft elasto-hydrodynamic lubrication. The model consists of an elastomer with spherical microdimples sliding at a constant velocity relative to a rigid and smooth counterpart in the presence of viscous lubricant. The hydrodynamic lubrication and the elasticity problems are solved simultaneously for the cases of full and partial texturing of the elastomer surface. Load carrying capacity and friction force are evaluated by integration of the pressure and shear stress fields in the viscous lubricant, respectively. A parametric analysis is performed to obtain the optimum surface texturing parameters for maximum load and minimum friction.     

INDUCTION-HEATED TOOL MACHINING OF ELASTOMERS—PART 2: CHIP MORPHOLOGY, CUTTING FORCES, AND MACHINED SURFACES

The induction-heated tool and cryogenically cooled workpiece are investigated for end milling of elastomers to generate desirable shape and surface roughness. Elastomer end milling experiments are conducted to study effects of the cutting speed, tool heating, and workpiece cooling on the chip formation, cutting forces, groove width, and surface roughness. At high cutting speed, smoke is generated and becomes an environmental hazard. At low cutting speeds, induction heated tool, if properly utilized, has demonstrated to be beneficial for the precision machining of elastomer with better surface roughness and dimensional control. Frequency analysis of cutting forces shows that the soft elastomer workpiece has low frequency vibration, which can be correlated to the surface machining marks. The width of end-milled grooves is only 68 to 78% of the tool diameter. The correlation between the machined groove width and cutting force reveals the importance of the workpiece compliance to precision machining of elastomer. This study also explores the use of both contact profilometer and non-contact confocal microscope to measure the roughness of machined elastomer surfaces. The comparison of measurement results shows the advantages and limitations of both measurement methods.     

大型空间机械臂关节力矩传感器的设计

设计了大型空间机械臂关节力矩传感器,采用Pro/E建立了弹性体的模型,使用ANSYS Workbench对弹性体进行了有限元分析,对比2种弹性体模型的灵敏度和线性度,最终选择剪切轮辐式弹性体;对设计的传感器进行标定,计算其静态特性指标,满足设计要求。     

MEMS magnetometer based on magnetorheological elastomer

To develop a simple and low-cost MEMS magnetometer, a novel sensor based on the magnetostrictive effect of magnetorheological elastomer is proposed. The micromechanical sensor consists of a silicon sensitivity diaphragm embedded with a piezoresistive Wheatstone bridge, and a magnetorheological elastomer layer attached on the sensitivity diaphragm. The interaction between the magnetic field and the elastomer generates a deflection of the sensitivity diaphragm, which changes the piezoresistance and unbalances a Wheatstone bridge. The experimental results show that the sensor has good linearity in the magnetic field range of 0-120 kA/m and the saturation magnetic field is ∼150 kA/m. This simple, low-cost, low-power sensor is easily integrated with electronic circuits using the MEMS processes.     

平行梁式称重传感器的有限元分析

称重传感器弹性元件的结构直接影响传感器的测量精度,根据平行梁式称重传感器的结构和特点建立了力学模型,用AutoCAD二次开发自动生成有限元网格,针对线段相交三种情况处理,使得被打破的"网格"成为结构离散图,由此生成有限元模型,通过在其它尺寸不变的情况下分别改变各个结构尺寸,从而找出弹性元件各结构尺寸对输出应变的影响规律,最后利用ViziCAD对模型进行了有限元应力应变分析并将样品输出灵敏度的计算值与实测值进行比较,二者结果较为吻合,利用有限元辅助分析设计,可以提高生产精度及效率.