摘要近年来中国对于铁矿粉的进口需求日益增大，加上国外进口铁矿粉品种、质量参差不齐，不同地区进口铁矿粉含铁量差异很大，这对铁矿粉的取样检测装置提出了更高的要求。

本设计针对铁矿粉的自动取样和检测，通过可编程逻辑控制器（PLC）编辑内部程序控制外部的电机实现正反转、中断延时、停止等功能，从而实现取样铲的定时旋转取样、放样、检测的目的。同时，本设计中还运用到压电片传感器以触发装置的取样放样运动。60945

PLC简单易学,可靠性高。三相异步电机是一种常用的机电执行元件,它可方便实现正反转的控制，并且其结构简单，制造方便，运行性能好，价格便宜。因此在众多领域有着极其广泛的应用。

毕业论文关键词  控制系统  PLC逻辑控制  传感器  三相电机

毕业设计说明书（论文）外文摘要

Title   Iron Ore Fines Automatic Sampling Device Designing                     

Abstract

In recent years, China's import demand for iron ore is increasing, in addition, imported iron ore are of varying qualities, imported iron ore in different regions varies greatly in iron content, which puts forward higher requirements to iron ore sampling detection device.

This device is designed for the iron ore automatic sampling and testing, using the programmable logic controller (PLC) to edit the internal procedures to control external motors rotating forward and backward, interrupt latency, stop and other functions, in order to achieve the purpose of rotating sampling ,lofting and detecting of the samples. Meanwhile, the design also applied to the piezoelectric sensor to trigger the movement of the sampling device.

PLC is easy to learn, and of high reliability. Three-phase asynchronous motor is a common electromechanical actuator, which can easily achieve the control of rotating forward and backward, and it is a simple structure which is easy to operate, well performed, and low in price. Therefore, it has an extremely wide range of applications in many areas.

Keywords  Control system  PLC logic control  sensor  phase motor

1  绪论 1

1．1  设计背景及意义 1

1．2  系统设计的任务 1

1．3  设计方案概述 1

1.3.1  总体分析 2

1.3.2  方案框图 2

2  机械结构设计 3

2．1  机构设计概述 3

2．2  机构运动和三维结构简图 3

2.2.1  机构运动简图及说明 3

2.2.2  机构三维简图及说明 4

3  PLC和电机控制介绍 8

3．1  PLC概述 8

3.1.1  PLC的定义 8

3.1.2  PLC的特点 8

3.1.3  PLC的基本结构及其应用 8

3．2  三相电机正反转控制 10

4  总体方案设计 12

4．1  机构和电机运动设计介绍 12

4．2  电机运动的控制设计 12

4.2.1  S7-300介绍