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一种基于PC机的轴类零件矫直机自动控制系统 总被引:2,自引:0,他引:2
前言在汽车、拖拉机、机械等行业中 ,常需要对轴类零件进行矫直。通常采用的方法是人工测量、手工矫直或人工测量、机械矫直 ,这种轴类零件的人工矫直 ,不但精度低 ,劳动强度大 ,而且不能实现在线测量 ,大大限制了我国工业技术水平的提高。针对上述情况 ,本文设计了一种由 PC机控制的矫直机自动控制系统 ,从变形量的测量到零件的矫直 ,整个过程实现了自动控制。1 轴类零件矫直机的工作原理及工作过程轴类零件矫直机主要由传动、测量、矫直和自动控制 4部分组成。传动部分主要包括顶尖和平台 ,顶尖的松开和夹紧用同步电机直接驱动的正反向… 相似文献
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轴类零件的加工是机械加工中常见的制造形式,利用数控车床进行轴类零件的批量加工能够很大程度的提高生产效率,同时提高复杂零件的加工质量。通过对轴类零件加工工艺分析过程的介绍,举例说明了指定轴类零件的工艺制定过程,并对该零件进行了数控仿真加工,以保证工艺和编程的正确性。 相似文献
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对简单几何形体——轴类切削件残余应力产生的原因进行了分析,建立了轴类零件表面残余应力经过时效处理后的尺寸变形量数学模型;并由算例计算出表面残余应力实际引起的变形量,指出该值在机器误差中的影响不容忽视。对于轴类件,由残余应力引起的变形量同残余应力的分布函数状况有关,而同零件尺寸无关。 相似文献
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《Journal of Agricultural Engineering Research》1998,69(3):249-254
A model to represent the discolouration of dried powder of carrots as a function of temperature was developed. Two types of carrots, Asian and European, containing large amount of lycopene and β-carotene, respectively, were tested. The dried powder was stored under an atmosphere with O2and at three different temperatures, 5,20 and 35°C. The surface colour of the powder was monitored during storage by a Hunter colour ratioa/b. In the proposed model, the rate of oxidation was assumed to be represented by the product of the fraction of concentration of oxidized pigment at arbitrary time and a specific rate of oxidation of pigment. The rate parameters in the proposed model were calculated by fitting the experimental data with smooth curves by trial and error at the end of the induction period but before discolouration took place. The frequency constant and activation energy, expressing the temperature dependence of the rate parameters, were expressed by the Arrhenius relation. The simulation results of a Hunter colour ratioa/bof dried powder at 25°C showed good agreement with the experimental data, suggesting that the proposed model was effective for the prediction of discolouration of dried powder of both types of carrot. The use of the induction period in the manner described may enable the shelf life of dried powder to be predicted. 相似文献
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感官检验棉花的品级,这是农村常见的一种检测手段.它的一个主要特点就是存在不确定性.这是由于检验员的品级检验水平存在一定的差异,其中有很多因素制约着检验的结果.文章对影响感官检验结果的因素进行了系统的分析. 相似文献
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The fractional outflow rate of water from the rumen, measured as the rate of disappearance of the chromium complex of ethylenediamine tetra-acetic acid, was related to a number of dietary factors. A multiple regression equation was derived which expressed fractional outflow rate as a function of the intakes of dry matter, ash, acid-detergent fibre and crude protein.The data analysed consisted of 243 observations for sheep on 59 diets, including forage, concentrate and mixed diets. The ranges covered by the data were: fractional outflow rate 0.7–3.6 day?1; dry matter intake 560–1400g/day; ash 4–30%, acid-detergent fibre 7–41%, crude protein 5–26 % of dry matter; there were no observations for sheep of less than 34 kg liveweight.The equation accounted for 56·3 % of the total variance. Between-sheep variance could not be calculated for the whole of the data but was undoubtedly substantial since, for a sixth of the data, it was known to account for 38 % of the total variance. 相似文献
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从灾害经济学的角度探讨了城镇供水优化调度的必要性和可能性,认为在缺水不可避免的情况下,对供水进行优化调度可以减小缺水带来的损失,产生较好的减灾效益,特别是可以大大减小严重干旱的灾害效应。并根据水资源的特性,提出了缺水损失的计算模式以及优化调度的原则和方法。 相似文献