In order to solve the problems of the traditional mine ventilation system"stop and switch"mode,such as large fan starting wind resistance,large air volume fluctuation and gas accumulation caused by the shutdown switching process,this paper proposes a control strategy of non-stop switching of mine main fan based on fuzzy PID control,and uses PLC as the control core and industrial Ethernet as the communication network to design the control system.The remote intelligent control of the opening and closing angle of the vertical and horizontal throttle keeps the air volume constant during the fan switching process and effectively improves the stability of the fan switching process.
Tool setting is a key step before CNC turning of parts.Accurate and fast tool setting is an important prerequisite for ensuring the accuracy and efficiency of CNC turning.Taking the commonly used outer and inner contour cutting tools in CNC turning as examples,virtual simulation software was applied to deeply explore the tool setting methods of various types of turning tools.These provide theoretical basis and simulation reference for tool setting for operators engaged in CNC turning machining.
碳化硅外延设备是囊括了高温、真空、运动、气体、电路、水冷等多学科、高危险的精密复杂设备.碳化硅外延生长需要在高温、低真空的环境下通入易燃易爆有毒工艺气体,因此设备的密封性尤为重要.介绍了利用控制系统对碳化硅外延设备自动检漏的方法,能够方便维护人员进行操作,大大缩短检漏时间.
双伸缩立柱是矿用液压支架的重要组成部分,详细阐述了煤矿用液压支架双伸缩立柱维修的拆装工具.在双伸缩立柱的拆解和装配作业中利用创新设计的液压固定式双伸缩立柱拆装机取代了传统的机械固定式拆装机,优化了作业工艺,减少了操作工序,降低了工人劳动强度,提升了工作效率.实际应用结果表明,液压固定式系统稳定,生产中操作流畅,创新设计的拆装机同时满足质量和安全要求.
牙弓曲线是口腔正畸矫治的基础,在临床上需要对牙弓曲线进行形状分析和测量.首先基于网格显著性初次筛选网格特征点,然后再利用网格特征点与咬合平面的夹角和距离筛选出初始参照点;接着将三维模型上选中的初始参照点投影到咬合二维平面,在二维平面上用四次多项式拟合映射点;最后快速、自动、精确地得到牙弓线.绘制出来的牙弓线可以用来辅助正畸医师判断牙齿错颌的情况,对患者进行诊断,设计并制定正畸计划.
