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101.
Gate location design in injection molding of an automobile junction box with integral hinges 总被引:5,自引:0,他引:5
Polymers such as polypropylene or polyethylene offer a unique feature of producing an integral or living hinge for automobiles, which can flex over a million times without causing a failure. However, due to increased fluidity resistance at hinges during molding, several defects such as short shot or premature failure can occur with the improper selection of gate locations. In this paper, a design guideline was induced by investigating resin flow patterns depending on several gate positions obtained by numerical analyses of a simple strip with a hinge. The analyses of the simple strip part showed that the resin at the hinge did not flow until the other side of the strip was filled. Once the resin at the hinge did not flow for a long time enough to be solidified, defects such as short shots or hesitation marks formed. For a practical application of the design guideline determined, four gate systems for an automobile junction box were designed. It was found that the properly determined gate location leads to better resin flow and shorter hesitation time. Finally, injection molding tryouts using a mold that was designed by one of the proposed gate systems were conducted. The experiments showed that hinges without defects could be produced by using the designed gate location to assure the induced design guideline to be reasonable. 相似文献
102.
分析了基座成型的特殊性 ,从多年的工作实践中总结了一套利用制件特征解决此类模具型芯定位的方法。所举的实例对其它类型产品的型芯以至于扩展到各种定、动模镶件的定位结构具有一定的参考意义。 相似文献
103.
全面分析介绍了武汉钢铁(集团)公司在板带材生产和工艺装备方面的发展、主要技术进步和所取得的成就,并提出武钢今后板带材生产技术研究的方向是实现高效、低耗、优质及清洁生产。 相似文献
104.
105.
A new thermomechanical model of cutting applied to turning operations. Part II. Parametric study 总被引:2,自引:0,他引:2
In Part I of this work, Molinari and Moufki [Int. J. Mach. Tools Manufact., this issue], an analytical model of three-dimensional cutting is developed for turning processes. To analyse the influences of cutting edge geometry on the chip formation process, global effects such as the chip flow direction and the cutting forces, and local effects such as the temperature distribution and the surface contact at the rake face have been investigated. In order to accede to local parameters, the engaged part in cutting of the rounded nose is decomposed into a set of cutting edge elements. Thus each elementary chip, produced by a straight cutting edge element, is obtained from an oblique cutting process defined by the corresponding undeformed chip section and the local cutting angles. The present approach takes into account the fact that for each cutting edge element the local chip flow is imposed by the global chip movement. The material characteristics such as strain rate sensitivity, strain hardening and thermal softening, the thermomechanical coupling and the inertia effects are considered in the modelling. A detailed parametric study is provided in this paper in order to analyse the effects of cutting speed, depth of cut, feed, nose radius and cutting angles on cutting forces, global chip flow direction and temperature distribution at the rake face. The influence of friction at the tool–chip interface is also discussed. 相似文献
106.
在研究MasterCAM后置处理程序格式的基础上,开发出适合SIEMENS数控系统的专用后置处理程序,解决了由MasterCAM生成的数控程序不能直接用于SIEMENS数控铣床系统加工的问题. 相似文献
107.
Naoji Shiroma Ryo Miyauchi Akira Nagafusa Youhei Haga Fumitoshi Matsuno 《Advanced Robotics》2015,29(3):149-163
In robot teleoperation, a robot works as a physical agent at a remote site for a robot operator. There are mainly two tasks in robot teleoperation using camera images: environment recognition using visual information and robot control according to the recognition. In this paper, we propose a gaze direction based vehicle teleoperation method with an omnidirectional image stabilization and an automatic body rotation control. In the proposed method, we manage above two tasks in the same manner that are usually treated separately. This method is an intuitive vehicle teleoperation method where an operator do not need to have concern about vehicle body orientations and can absorb differences of vehicle driving mechanisms. That is, this method frees an operator from being bothered from controlling a vehicle and the operator can concentrate on where he/she intends to go. This method mainly consists of two technologies: an omnidirectional image stabilization technology and automatic body rotation control. The conducted experiments show effectiveness of the proposed method. 相似文献
108.
109.
微震定位系统中拾震器布阵研究 总被引:1,自引:0,他引:1
对微震监测中拾震器阵列进行科学有效的布置是保证微震定位系统能有效运行的一个关键条件,设计了4种拾震器阵列布设方案,使煤矿中微震定位监测系统运行得更加科学有效.首先建立复杂地质模型,利用微变网格射线追踪正演模拟出微震源起震到拾震器阵列接收信号的过程,然后在施加随机扰动的情况下,利用粒子群-神经网络算法(PSO-BP)反演推算出震源位置,最后通过震源位置的误差来分析各个布阵方案的特点,同时分析了阵列中拾震器数量的合理值.研究结果表明,在微震监测系统中拾震器利用率最高的情况下,可以给出准确、合理、有效的拾震器布阵方案. 相似文献
110.
首先针对个人航位推算系统中计步算法的阈值设定问题,提出了一种基于有限状态机的阈值自学习算法.通过该算法可以在较短的时间内(10s)获得自适应阈值,提高计步算法的准确性.然后在利用该阈值进行计步的同时,对连续步态进行分割,并以分割结果作为动态窗口进行主成分分析,可以获取目标运动的方向.此外,通过利用运动步态模型中加速度变化的规律可以有效解决180°模糊问题.实验分析结果表明,相比于固定窗口的 PCA 分析方法,基于动态窗口的 PCA 在数据处理量降低61.2%的情况下,其准确度提高了11.1%. 相似文献