1、 摘 要 随着现代信息技术的飞速发展和工业自动化技术的逐步实现，人们对建筑物 内的安全性和灾害预警系统更加重视，为预防楼房内的火灾，人们已采取许多方 法来防范火灾的发生。其中就包括通过信息化和自动化的方法来检测楼房内的烟 雾和温度，达到检测火灾的目的。 本论文以电阻式烟雾传感器和单片机技术为核心并与其他电子技术相结合， 设计出一种技术水平较好的火灾报警器。其中选用 MQ-2 型半导体可燃气体敏感 元件烟雾传感器实现烟雾的检测，以 AT89S52 单片机和 MQ-2 型半导体电阻式烟 雾传感器为核心设计的火灾报警器可实现报警、故障自诊断、浓度级别显示、报 警限设置、温度显示及与温度报警值设定等功
2、能。是一种结构简单、性能稳定、 使用方便、价格低廉、智能化的火灾报警器，具有一定的实用价值。 关键词：火灾报警；单片机；烟雾传感器；温度传感器； Abstract With the rapid development of modern information technology and industrial automation technology gradually realize, people on the structures within the safety and disaster warning system more attention, to prevent the
3、fire in the building, people have taken many methods to prevent fire. Including through informatization and automated method to detect the smoke in the building and temperature, achieve the purpose of fire detection. In this paper, resistance type smoke sensor and single-chip microcomputer as the co
4、re technology and electronic technology, designs a technology better fire alarm. The selection of MQ-2 type semiconductor gas sensitive element smoke sensor smoke detection. The selection of AT89S52 chip, the integration of the A/D conversion, hardware multiplier, hardware pulse width modulator and
5、other resources. With AT89S52 MCU and MQ-2 type semiconductor resistor type smoke sensor as the core design of the fire alarm can alarm, fault diagnosis, concentration level display, alarm limit settings, temperature display and temperature alarm value setting and other functions. Is a kind of simpl
6、e structure, stable performance, convenient operation, low price, intelligent fire alarm, has a certain practical value. Key words: Fire alarm; Single chip microcomputer; The smoke sensor; The temperature sensor I 目 录 第第 1 1 章章 绪论绪论 1 1 1.1 课题研究背景及意义 1 1.2 火灾报警器的发展历程和发展现状 1 1.3 论文主要内容及结构安排 3 第第 2 2 章章 总体方案论证与设计总体方案论证与设计 4 4 2.1 设计要求 4 2.2 总体设计方案 4 2.3 各功能模块方案选择 5 2.4 本章小结 6 第第 3 3 章章 系统硬件设计系统硬件设计 8 8 3.1 单片机最小系统电路设计 8 3.2 DS18B20 测温电路 10 3.3 四位数码管显示电路的结构和工作原理 12 3.4 MQ-2 烟雾传感器转换电路. 15 3.5 报警
