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1.
A reamer equipped with diamond bars of different grain size is described. Optimization of the reamer structure and geometry and also the preliminary hole diameter is considered, when different precision is required. The operating conditions and size of the diamond grains affect the reamer performance; recommendations for their selection are offered. The use of the new tool in machining precision holes is considered for various examples.  相似文献   

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空间凸轮机构精度分析的通用公式   总被引:3,自引:0,他引:3  
应用机构精度分析的微分法及概率论的基本概念 ,建立起了凸轮机构精度分析的统一随机模型 ,导出了常用空间凸轮机构精度分析的通用计算公式 ,为空间凸轮机构的精度分析打下了理论基础。  相似文献   

4.
轻型空间相机调焦机构的优化设计与精度试验   总被引:3,自引:0,他引:3  
根据轻型空间相机光学系统的特点以及相机的焦深,优化设计了一种适用于该类相机的调焦机构.为了满足相机总体要求,综合考虑重量、外型尺寸、刚度、误差等各方面的因素,选择丝杠和连杆配合使用的双滑块机构,将丝杠的转动通过连杆机构转换成调焦镜沿光轴方向的直线运动,实现了通过调整像面移动来解决离焦的问题.对该调焦机构在调焦范围内的调...  相似文献   

5.
The design and characteristics of a three-spectrum multielement photodetector device with a sensitivity range from 0.6 to 12.0 μm, which consists of three arrays of photodetectors having sensitivity ranges 0.6–0.9, 3–5, and 8–12 μm, are described. Methods of fabrication of photodetector arrays, the photodetector device as a whole, and its photoelectric characteristics are presented.  相似文献   

6.
针对精压机的工作特点,研究了如何利用ADAMS软件对精压机工作机构进行建模和运动学仿真,并将仿真结果与理论相比较,验证了仿真的正确性,对精压机工作机构的设计提供了指导,缩短了产品开发周期,降低了开发费用.  相似文献   

7.
This paper looks at the speciality application field of precision mechanisms, the tribological regime under which they operate, and the consequent requirements for precision lubricants. These include low evaporation rate, good drop cohesion, high ageing stability, resistance against contamination, and particularly an inertness in relation to polymers and lacquers. The range of lubricants available today is reviewed in relation to these requirements and to the materials likely to be used in precision instruments and mechanisms, and it is concluded that since no one lubricant can solve all the problems encountered in specific mechanisms, the selected lubricant is a compromise.  相似文献   

8.
Possible mechanism defects and errors that may be encountered during the selective precision synthesis of planar mechanisms are discussed in detail and suitable remedial measures recommended. These defects include dyadic assembly error, locking defect, branching defect and the sequential mismatch defect. By solving these problems, the selective precision synthesis method can easily be adapted to solving numerous planar kinematic synthesis problems.  相似文献   

9.
A quasioptimal method of antenna array control in information systems is proposed based on optimizing the integral parameters of an array in controlling the complex current amplitudes in some of the array radiators. Numerical calculations were performed which confirmed the validity of the analytical estimates. An estimate was obtained for the choice of the arrangement of uncontrolled elements of an antenna array that minimizes the decrease in the energy parameters of the antenna array with the quasioptimal control.  相似文献   

10.
高速精密平面定位机构的设计与应用   总被引:1,自引:0,他引:1  
面向先进电子封装等领域对高速精密定位机构的需求,结合两种新型平面定位机构,对直接驱动并联机构的运动弹性动力学建模与仿真、基于扰动观测器的控制策略进行了研究。  相似文献   

11.
The architecture of silicon multiplexers for multielement IR photodetectors is considered. A review is given of industrially oriented developments of linear (1 × 32, 1 × 288, 1 × 576) and matrix (32 × 32, 128 × 128, 160 × 128, 320 × 256) silicon multiplexers for mid- and far-IR photodetectors based on cadmium-mercury-tellurium, lead-tin-tellurium, and multilayer structures with quantum wells. An analysis is made of the temperature resolution of matrix IR photodetectors based on multiplexers with row and frame integration of photo signals using micrometer to deep submicron CMOS technologies. Typical parameters of the multiplexer and some of the infrared photodetectors designed at the Rzhanov Institute of Semiconductor Physics, SB RAS are given.  相似文献   

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土壤全量多元素的ICP-AES分析   总被引:5,自引:0,他引:5  
本文介绍土壤中多元素的ICP-AES分析方法。文中详细叙述了操作步骤,并给出了分析的精密度、准确度、检出限的数据及与其它分析方法的比较、讨论了干扰元素的影响及其消除的措施。  相似文献   

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发夹模具是当前模具行业中竞争比较激烈的模具之一,如何提高发夹模具曲面加工精度成为我们关注的焦点。本文从发夹模具加工工艺的角度出发,寻找影响发夹模具曲面加工精度的因素,针对其影响因素提出了改进的措施,提高了发夹模具曲面加工精度。  相似文献   

15.
An automatic system for measuring the quantum efficiency of multielement photodetectors applied in atomic emission spectral analysis is created. Results of measuring the quantum efficiency of BLPP-369 photodiode lines with different dopants and coating layers, and also lines of CCDs (Sony ILX-526A) are presented. It is shown that the quantum efficiency of photodiode lines between 180 and 360 nm is 0.3–0.5, which is 2–5 times greater than for ILX-526A CCDs with phosphor. The spread of quantum efficiency values of photodiodes in one BLPP-369 line is no more than 10%, and about 30% for lines from different batches.  相似文献   

16.
The concept of localization precision, which is essential to localization microscopy, is formally extended from optical point sources to microscopic rigid bodies. Measurement functions are presented to calculate the planar pose and motion of microscopic rigid bodies from localization microscopy data. Physical lower bounds on the associated uncertainties – termed centroid precision and orientation precision – are derived analytically in terms of the characteristics of the optical measurement system and validated numerically by Monte Carlo simulations. The practical utility of these expressions is demonstrated experimentally by an analysis of the motion of a microelectromechanical goniometer indicated by a sparse constellation of fluorescent nanoparticles. Centroid precision and orientation precision, as developed here, are useful concepts due to the generality of the expressions and the widespread interest in localization microscopy for super‐resolution imaging and particle tracking.  相似文献   

17.
用最小二乘法提高CCD干涉计量的精度   总被引:11,自引:3,他引:11  
本文针对相位型光栅的面形测量,用最小二乘法做二次曲线拟合,解决了CCD光学干涉计量中像素尺寸以及图像采集卡空间量化误差对测量精度的影响,使干涉条纹定位精度提高一数量级以上。对曲线拟合误差进行了讨论,给出了实测结果。  相似文献   

18.
本文针对相位型光栅的面形测量,用最小二乘法做二次曲线拟合,解决了  相似文献   

19.
介绍了多种多元共渗处理的渗剂配方及它们在生产中的应用。  相似文献   

20.
A procedure for grey‐scale conversion of energy dispersive spectroscopy X‐ray maps has been developed, which is particularly useful for the plotting of line composition profiles across modified layered engineering surfaces. The method involves (a) the collection of grey‐scale elemental maps, (b) the calculation of mean grey‐scale levels along strips parallel to the layered microstructure and (c) the conversion of grey‐scale line profiles into composition line profiles. As an example of the grey‐scale conversion method and its advantages for multielement and multiphase layered microstructures, the procedure has been applied to a layered microstructure that results from a plasma‐sprayed metallic MCrAlY coating onto a nickel‐superalloy turbine blade. As a further demonstration of the accuracy and amount of compositional data that can be obtained with this procedure, measured compositional profiles have been obtained for several long‐term isothermal heat treatments in which significant interdiffusion has taken place. The resulting composition profiles have greatly improved counting statistics compared to traditional point‐by‐point scans for the same scanning electron microscope time and may be considered as a rapid alternative to energy dispersive spectroscopy spectrum imaging. The composition profiles obtained may be conveniently compared with results of multicomponent thermodynamic modelling of interdiffusion.  相似文献   

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