共查询到20条相似文献,搜索用时 163 毫秒
1.
快速成型台阶误差分析及其降低措施 总被引:1,自引:0,他引:1
以FDM成型工艺程序为线索,分析可能影响FDM成型精度因素.研究了FDM快速成型原理导致的原理性误差,FDM快速成型是层堆积成型,成型件是层层堆积粘接而成,这就必然会形成台阶误差而影响成型件的表面精度.在分析台阶误差产生原因的基础上,找出影响台阶误差的因素及其变化规律,在此基础上提出减小台阶误差的措施.针对快速成型时采用逐层叠加制造的基本思想,对成型时的台阶效应引起的正偏差进行了分析计算,绘出了影响该误差的因素及其误差曲线图,供有关设计和制造技术人员参考. 相似文献
2.
快速制模是快速成型的主要应用之一,但成型件的精度难以达到快速制模对原型或型芯尺寸精度和表面精度的要求.系统分析了熔融堆积成型( FDM)工艺成型精度的影响因素,分析产生误差的根源及作用机理.针对FDM产生的误差,通过定性和定量分析,提出减小误差的途径和方法,并通过实例验证了解决翘曲变形和尺寸精度问题的方法,提高了原型的精度,对熔融堆积成型工艺精度的提高具有实际的参考价值. 相似文献
3.
随着熔融沉积(FDM)的进一步应用,制品成型精度成为FDM在工业发展中的关键问题。文中介绍了FDM的工艺原理,阐述了FDM系统中的主要工艺参数,并通过成型设备及实验分析了它们对成型制品表面粗糙度的影响。 相似文献
4.
5.
以FDM成型工艺程序为线索,分析影响FDM成型件表面硬度的因素。研究了温度对熔融沉积成型件表面硬度的影响。以汽车门把手为造型基础,分析影响汽车门把手精度、强度的因素,并提出相应的措施。用标准塑料硬度计测量在不同温度下加工的模型硬度,进而获取相应的数据,并据此得出成型室平均温度与成型件硬度变化曲线图。成型件的硬度与成型室温度有密切的关系,不同温度下加工的成型件硬度是不同的。此研究供有关设计和制造技术人员参考。 相似文献
6.
介绍了快速成型技术的基本原理;对立体光固化(SLA)、熔融沉积(FDM)、选择性激光烧结(SLS)和分层实体制造(LOM)这四种成型方法的工作原理、材料选择和精度影响因素进行了分析;介绍了快速成型的应用情况;在此基础上指出了快速成型技术的发展趋势。 相似文献
7.
8.
9.
10.
11.
12.
DHILLON B S 《机械工程学报(英文版)》2011,(5):899-904
As the differences of sensor’s precision and some random factors are difficult to control,the actual measurement signals are far from the target signals that affect the reliability and precision of rotating machinery fault diagnosis.The traditional signal processing methods,such as classical inference and weighted averaging algorithm usually lack dynamic adaptability that is easy for trends to cause the faults to be misjudged or left out.To enhance the measuring veracity and precision of vibration signal in rotary machine multi-sensor vibration signal fault diagnosis,a novel data level fusion approach is presented on the basis of correlation function analysis to fast determine the weighted value of multi-sensor vibration signals.The approach doesn’t require knowing the prior information about sensors,and the weighted value of sensors can be confirmed depending on the correlation measure of real-time data tested in the data level fusion process.It gives greater weighted value to the greater correlation measure of sensor signals,and vice versa.The approach can effectively suppress large errors and even can still fuse data in the case of sensor failures because it takes full advantage of sensor’s own-information to determine the weighted value.Moreover,it has good performance of anti-jamming due to the correlation measures between noise and effective signals are usually small.Through the simulation of typical signal collected from multi-sensors,the comparative analysis of dynamic adaptability and fault tolerance between the proposed approach and traditional weighted averaging approach is taken.Finally,the rotor dynamics and integrated fault simulator is taken as an example to verify the feasibility and advantages of the proposed approach,it is shown that the multi-sensor data level fusion based on correlation function weighted approach is better than the traditional weighted average approach with respect to fusion precision and dynamic adaptability.Meantime,the approach is adaptable and easy to use,can be applied to other areas of vibration measurement. 相似文献
13.
Direct current bias applied to hot flame diamond deposition produces smooth low friction coatings 总被引:3,自引:0,他引:3
As-deposited diamond coatings generally have a high surface roughness which results in a high friction coefficient and extensive wear of the counter material in sliding contact. Therefore several methods for smoothening diamond coatings have been proposed, such as laser polishing, molten metal etching, thermochemical polishing and mechanical polishing. All these methods have some disadvantage e.g. long processing time or high processing temperature. Furthermore, they are all post-deposition treatments i.e. the manufacture of these coatings requires at least two processing steps, deposition and smoothening. With the present method which combines d.c. bias with hot flame diamond deposition, a smooth diamond surface is produced during the actual growth of the film. No post-deposition treatment is necessary. The surface roughness is not dependent on the coating thickness which means that thick coatings with smooth surface can be produced. In fact, the method has a smoothening effect, i.e. rough surfaces can be made smooth. The method is comparable to conventional hot flame deposition of diamond as to growth rate and cost of producing the coatings. The coatings have a nano-crystalline structure and a surface roughness of Ra = 25 nm, and result in a friction coefficient of 0.1 or less in dry sliding and about 0.05 in water-lubricated sliding against cemented carbide. Their wear resistance is virtually the same as that of conventional diamond films. 相似文献
14.
这里就内圆磨床加工时的磨具修整和补偿进行了探讨。通过直观的分析,发现了在内圆磨削加工时的磨具修整和补偿量的对磨削精度影响规律;并提出了磨削加工时磨具修整和补偿的注意事项和措施,对磨削操作具有实际意义。 相似文献
15.
16.
17.
熔融沉积成形(FDM)是快速成型(RP)最有发展前途的工艺之一,掌握提高成形件精度的控制方法是推广其应用的重要途径。在分析FDM成形件精度影响因素的基础上,提出应用误差反向传播(BP)神经网络建立预测精度模型的方法。将主要影响因素作为BP神经网络模型的输入参数,并根据最小预测误差选择输入层和中间层的维数,确定了BP模型结构。利用多组实验数据进行模型训练,建立了BP神经网络模型。模型预测与实验测量的对比结果表明,模型的预测误差在6%以内,具有很高的预测精度,可以指导实际应用。 相似文献
18.
马素玲 《机电产品开发与创新》2007,20(2):165-166
针对模具制造中较精密细长斜型芯加工时,容易产生变形而无法保证加工精度的实际情况,笔者通过实例从斜型芯材料的选择以及利用线切割方法加工工件时加工配置方式、具体的加工顺序等方面提出了解决上述问题的具体做法. 相似文献
19.
在简述精密、超精密加工内涵和重要性的基础上,重点分析了影响精密、超精密加工的因素及采取对策。针对世界上一些发达国家研制开发精密、超精密加工技术已达到了很高技术水平的现状,提出了我国超精密加工的主要研究方向及目标。 相似文献
20.
加工误差产生的原因及分析 总被引:4,自引:0,他引:4
在机械加工过程中,由于各种因素的影响,加工出来的零件不可能与理想的要求完全符合,总会产生一些偏差,这种偏差就是加工误差。加工精度是指零件加工后的实际几何参数与理想几何参数的符合程度。加工误差和加工精度是从不同角度来评定零件的几何参数的。在实际生产中,都是用控制加工误差来保证加工精度,加工误差越小,加工精度越高,反之亦然。通过对影响加工误差的各种因素的分析,利用单因素分析法和统计分析法探索分析加工误差,找出减小加工误差的途径。 相似文献