机械5

目录 摘要................................................................................................................................................................1 Abstract...........................................................................................................................................................2 致谢词.............................................................................................................................................................3 绪论.................................................................................................................................................................4 第一章.常用元器件基本介绍....................................................................................................................5 1.1接触器..............................................................................................................................................5 1.1.1接触器的型号说明...................................................................................................................6 1.1.2接触器的选用...........................................................................................................................6 1.2控制继电器......................................................................................................................................8 1.2.1电磁电流继电器、电压继电器及中间继电器........................................................................8 1.2.2时间继电器...............................................................................................................................9 1.2.3热继电器.................................................................................................................................11 1.2.4速度继电器.............................................................................................................................13 1.2.5信号继电器.............................................................................................................................14 1.2.6零压继电器.............................................................................................................................15 1.3刀开关与低压断路器....................................................................................................................15 1.3.1低压刀开关.............................................................................................................................15 1.3.2低压断路器.............................................................................................................................17 1.4熔断器............................................................................................................................................19 1.4.1常用的熔断器.........................................................................................................................19 1.5半导体二极管及其基本应用........................................................................................................20 1.6三极管的分类及应用....................................................................................................................21 1.7晶闸管及其应用............................................................................................................................21 第二章.电力拖动方案的确定..................................................................................................................25 2.1电动机简介....................................................................................................................................25 2.2电力系统的确定............................................................................................................................25 2.2.1电力拖动系统的选择概述.....................................................................................................25 2.2.2电动机的比较、选择.............................................................................................................26 2.2.3电动机的结构形式.................................................................................................................28 2.3电动机工作制的分类....................................................................................................................28 2.4电动机的调速、启动、制动.........................................................................................................29 第三章.电气控制电路中的保护环节......................................................................................................31 3.1主要的保护种类和原理................................................................................................................31 3.1.1过载保护...................................................................................................................................31 3.1.2短路保护...................................................................................................................................32 3.1.3限位保护...................................................................................................................................32 3.1.4电气互锁与自锁.......................................................................................................................33 3.1.5过负荷保护...............................................................................................................................33 第四章.磨床的电气控制设计..................................................................................................................34 4.1设计概述........................................................................................................................................34 4.2控制电路的特点............................................................................................................................35 4.3交流控制电路分析........................................................................................................................35 4.4电磁吸盘励磁于退磁的控制........................................................................................................37 4.4.1电磁吸盘励磁控制...................................................................................................................39 4.4.2电磁吸盘退磁控制...................................................................................................................40 参考文献.......................................................................................................................................................41