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由于相移式横向剪切干涉仪相移单元的分辨率、精度等参数直接影响其测试物镜波像差的精度,本文根据相移式横向剪切干涉测试原理,设计了采用宏微复合运动模式的相移组件,该相移组件可在25 mm行程内实现纳米级的相移运动.重点分析了柔性铰链复合四杆结构微动单元初始设计参数间的数学规律,计算了铰链刚度与弱截面应力,并给出了具体的设计实例.采用有限元分析方法,对设计实例中微动单元的相移量与压电陶瓷(PZT)出力之间的作用规律进行仿真,并分析了相移精度.结果显示,PZT在促动力输出范围内可促动0.1 mm~1 nm的一维相移运动,理论精度优于3.5 nm.微动单元的开环标定测试结果表明,相移微动单元的实际精度优于5 nm. 相似文献
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分析了横向剪切式切纸的工作原理及影响手帕纸剪切的主要因素,利用Visual C 进行了剪切式切纸设计参数的优化设计,并提供有效的验算方法,为剪切式切纸提供了优化设计平台与验算依据. 相似文献
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随着建筑行业的迅速发展,钢筋混泥土结构广泛地应用于建筑中,一旦发生自然灾害,钢筋网结构将给营救带来巨大的困难。为提高钢筋网的剪切效率,提出设计了一款钢筋网挤压剪切装置。首先,在SolidWorks软件中设计了挤压剪切装置的三维结构模型,其主要包含挤压装置与剪切装置两大部分,并通过液压缸提供所需的挤压力与剪切力。然后,在simulation插件中对挤压钳和剪片进行了有限元分析,结果表明,设计的挤压钳和剪片能满足挤压和剪切作业时力学性能,能正常完成挤压和剪切任务。 相似文献
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冲床剪切是圆棒料常用的下料方法。由于其具有效率高,料耗少,成本低、操作简单等优点而被广泛应用于大批量生产中。图1为常用的圆棒料剪切装置。这种装置由一个管状切料模和一把开有与工件直径相当之圆弧刃口的切刀,再加上一个可调节的定位挡铁组成。切料模固定在工作台上,切刀安装在冲床滑块上随之往复运动完成对棒料的剪切。该装置结构简单,制造方便,易于操作,因此应用十分广泛。但这种下料装置的缺点 相似文献
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依据圆周剪切的基本原理,设计了一套圆周剪切装置,阐述了设计的基本要求和设计的基本方案.并利用ANSYS软件对装置分别进行了结构分析.分析结果表明,本装置符合强度要求. 相似文献
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“一面两销”定位是机械加工中工件与夹具、夹具与机床定位方式中最常用的一种形式,介绍了一种可调整式“一面两销”定位装置的设计特点,通过定位销基座的方式完成定位销和机床夹具本体的连接,同时具有位置可调性,从而满足定位销的位置优化。相对于固定式“一面两销”定位装置,在专用夹具设计应用中具有较大的便捷性、优越性和兼容性,能够针对夹具定位误差进行补偿校正,有效地消除各种定位误差带来误差影响,提高一面两销定位精度,大大提高工件加工的位置精度。 相似文献
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Quick stop devices (QSDs) are used for collecting samples of chip roots which are representative of the deformation in the primary shear deformation zone, taking place during dynamic cutting conditions. This paper reports on a safe, easy-to-operate and fast-retracting quick-stop device that has been designed, fabricated and tested. It uses a concept thought to be new to this field where stored strain energy is used for retracting the tool: existing QSDs operate on the principle of failure of a pin under shear stress, which is slower compared to the failure of a pin under tensile stress. The proposed device operates on the principle of failure of a tensile pin rather than a shear pin. It permits the collection of chip roots for in depth study of the mechanisms of deformation in the primary and secondary shear deformation zones. The time taken for the withdrawal of the tool from the workpiece has been estimated theoretically as well as experimentally. The chip roots were collected under different cutting conditions. 相似文献
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本文介绍了轴销剪切式称重传感器的结构与特点,受力分析与理论计算.在深入分析各种测量误差来源的基础上,提出了设计和应用中应注意的问题. 相似文献
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Guosheng Su Zhanqiang Liu 《The International Journal of Advanced Manufacturing Technology》2013,65(9-12):1735-1740
Saw tooth chip is a typical characteristic encountered in high-speed machining. It consists of nearly undeformed segments and highly sheared concentrated shear bands. However, no consensus on the formation of the concentrated shear band has been reached though several saw tooth chip formation models have been built. In this paper, the concentrated shear band formation procedure is analyzed based on a new proposed saw tooth chip formation model. Cutting experiments have been conducted to validate the proposed mode. It shows that the plastic side flow and elastic compression of the uncut chip are crucial for the concentrated shear band formation. The localized shear at the inner end (tool tip side) of the primary shear plane firstly takes place under the indentation of cutting tool. Then, the second localized shear is produced at the outer end (free surface side) of the primary shear plane due to stress concentration there, after which the whole concentrated shear band forms. The stress transition at the outer end of the primary shear plane makes the second localized shear easier evolve into cracks. Influences of material brittleness and cutting speed on initiation and propagation of the concentrated shear band are also analyzed. 相似文献
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针对某星载设备信息箱中插槽式固定电路板在力学试验中出现引脚断裂这一问题,在对电路板上的元器件简化为等质量立方体的基础上,用Solidworks软件对信息箱机械结构建立了精确的几何模型,用MSC/Nastran软件进行了模态分析.在模态分析的基础上改进了电路板的结构设计,对改进前后的模型进行了模态、随机振动响应分析和试验.分析结果和试验结果都表明改进后的结构力学特性明显增强,问题得以较好解决. 相似文献
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Binglin Li Xuelin Wang Chenggang Li Xingxing Li 《Machining Science and Technology》2013,17(4):453-484
A new analytical cutting force model is presented for oblique cutting. Orthogonal cutting theory based on unequal division shear zone is extended to oblique cutting using equivalent plane approach. The equivalent plane angle is defined to determine the orientation of the equivalent plane. The governing equations of chip flow through the primary shear zone are established by introducing a piecewise power law distribution assumption of shear strain rate. The flow stress is calculated from Johnson-cook material constitutive equation. The predictions were compared with test data from the available literature and showed good correlation. The proposed model of oblique cutting was applied to predict the cutting forces in end milling. The helical flutes are decomposed into a set of differential oblique cutting edges. To every engaged tooth element, the differential cutting forces are obtained from oblique cutting process. Experiments on machining AISI 1045 steel under different cutting conditions were conducted to validate the proposed model. It shows that the predicted cutting forces agree with the measurements both in trends and values. 相似文献
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