新型减速器优化设计

通过对摆线针轮行星减速器设计的过程分析 ,进行了多目标优化设计 ,建立了摆线针轮行星减速器优化设计的数学模型 ,经实例计算表明 ,该方案是可行的     

界面极化效应对AlxGa1-xN/GaN异质结pin探测器光电响应的影响

设计了正面入射的探测波长范围限制在326～365nm的AlxGa1-xN/GaN异质结pin光电探测器.利用自洽求解薛定谔-泊松方程计算了AlxGa1-xN/GaN异质结在无极化、完全极化和部分极化的能带图,结合光电响应谱的模拟,分析了界面极化效应对AlxGa1-xN/GaN异质结pin紫外光电探测器响应特性的影响并提出了改善方法.     

对3F机组调速器推拉杆压板上定位销扭断的分析——以水布垭电站为例

3F机组调速器推拉杆压板上定位销扭断分析是机组运行中的常见问题,原因比较复杂,有时可能是好几种原因综合的结果。对3F机组调速器接力器推拉杆压板上定位销扭断的原因进行了分析,提出了一系列的技术改进措施,并针对水布垭机组提出了解决方案。     

大型射电望远镜多馈源切换机构的设计

针对大型射电望远镜配备的馈源频段多、定位精度高和切换时间短的特点,结合工程实践,介绍了一种通过馈源旋转方式来实现多组馈源相互切换并用锁定销来精确定位的设计,通过该设计使每个馈源的相心均能准确到达天线的第二焦点位置并锁定。对整个机构的结构形式、功能进行了阐述,并对馈源的定位误差加以分析。同时,通过采用可倾覆使用的绕线机构,解决了天线在不同仰角条件下换馈机构旋转时带来的电缆缠绕问题。     

钢结硬质合金在电机冲片冲模中的应用

主要介绍了钢结硬质合金在冲片模具中的应用，模具加工工艺及寿命分析，说明其使用效果良好。     

桥式双斗轮双向混匀取料机的改造

济钢原料厂二次混匀料场取料机斗轮系统原采用销齿传动型式，存在系统不稳定、零部件劣化快、寿命短等缺陷。经设备技术改造由链传动替代销齿传动后，故障率下降，减轻了维修工作量，仅备件费一项每年就节约９０万元，实现了向４台地机供料的二次混匀料场出料率达１００％的目标。     

CFD analysis of natural convection heat transfer augmentation from square conductive horizontal and inclined pin fin arrays

Numerical investigations on natural convection heat transfer from a vertical isothermal plate with pin fins have been made by solving the Navier–Stokes equation along with the energy equation. Average Nusselt number for the plate with different configurations of pin fins have been obtained. It was observed that the maximum increase of the average Nusselt number occurs at S_v/L?=?0.2 for θ?=?45° with fin height of 24?mm (H/t?=?8). The average Nusselt number increases with fin aspect ratio and decreases with angle of inclination. There is not much difference between the average Nusselt number for in-line and staggered arrangement of fins for the range of parameters studied in the present work. A correlation is developed to predict the average Nusselt number of the plate as a function of fin spacing in stream- and span-wise direction, aspect ratio of fins and its angle of inclination.     

电液控制的销齿翻车机液压传动系统设计

目前销齿翻车机控制系统主要采用机械联动或者是机电结合使用,文中研究机电液一体化技术,采用集中液压站控制实现动作的无级调速,为后续的使用寿命提供理论依据。     

Friction and wear behavior of styrene butadiene rubber‐based composites reinforced with microwave‐devulcanized ground tire rubber

In this work, the tribological properties of a new material obtained by revulcanization with styrene butadiene rubber (SBR) and devulcanized ground tire rubber (GTR) were investigated. GTR was devulcanized using the microwave method at a constant power while varying the microwave exposure time. Devulcanized rubber (DV‐R) and untreated GTR were revulcanized by mixing with SBR at different rates (10, 30, 50 phr). To determine friction and wear characteristics of the samples, pin (ball) on disc and abrasion tests were conducted. Scanning electron microscopy (SEM) was employed to observe the worn surfaces of the composites to correlate the experimental test results to the wear mechanisms. All of these tests and experiments were performed on original vulcanized rubber samples for comparison. The composites exhibited different friction and wear behavior due to morphology, dispersion behavior and devulcanization functionalization of ground tire rubber. In general, DV‐R/SBR composites exhibited improvement in both mechanical and tribological properties. However, the enhanced compatibility of DV‐R resulting from the specific chemical coupling of DV‐R with SBR was crucial for the mechanical, friction and wear properties. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42419.     

一种3线制半双工SPI接口设计

SPI(serial peripheral interface)总线是由Motorola公司提出的一种4线制同步串行外设总线接口,包括时钟、使能、输入和输出4根引脚,主要用于CPU与各种外围器件以串行方式进行通信。为了进一步减少接口,介绍了在一款用于射频芯片数据/控制接口的3线制SPI接口的电路设计,通过采用半双工工作模式,接口电路在减少一个引脚的情况下实现双向通信。介绍了3线制SPI接口的电路结构及其工作原理。该SPI接口在0.18μm工艺下实现的版图总尺寸约为240μm×460μm,在10 MHz工作频率下的功耗约为2 mW,通过仿真验证,3线制SPI接口功能正确。