基于单片机的瓦斯浓度检测器的设计毕业设计论文.docx

PAGE \* MERGEFORMATII 摘要 本课题设计的是用单片机控制的瓦斯浓度报警监控仪，是采用以金属氧化物SnO2为主体材料制成的N型半导体气敏元件制成的瓦斯浓度测量仪，适用于中小型煤矿井下各作业场所中测量空气中的瓦斯浓度。仪器能够根据瓦斯浓度报警限(1.00%)进行声、光报警。 仪器由CPU、敏感元件、A/D转换电路、显示电路、报警电路等组成。其中CPU是监控仪的核心，完成数据采集、处理、输出、显示等功能；敏感元件是准确检测瓦斯气体含量的主要元件之一，其输出是与瓦斯浓度相对应的电压信号；A/D转换电路把放大了的电压信号由模拟信号变为数字信号送入CPU；显示电路则显示实时瓦斯浓度；报警电路对超限瓦斯浓度进行报警。 该仪器的特点是测量范围宽，精度高；结构简单，体积小，成本低；可靠性和稳定性好，是一种电路设计新颖、参数测量准确、操作方便的矿用瓦斯浓度监控仪。 关键词：CPU；A/D转换；气敏元件；报警 Abstract This paper designs gas alarm monitor, which is made of metal oxide SnO2 as the main material for n-type semiconductors gas sensor. It is applicable to small and medium-sized coal mine in the measurement of workplace air concentration of gas. Apparatus, which is according to gas concentration alarm limit (1%), carry out sound and light alarm. Apparatus consists of CPU, sensitive element, A/D conversion circuit, display circuit and alarm circuit. CPU, which is the core of the monitor, finishes data’s acquisition, processing, output, display and other functions; sensitive element that is used of the accurate detection of gas content is one of the main components, and its output isthe voltage signal which is corresponding to the gas-concentration; A/D conversion circuit exports the amplified voltage signal from the analog signal into digital signal to the CPU; display circuit displays the real-time gas-concentration; the alarm circuit alarms to the limited gas-concentration. The apparatus is characterized by a wide measurement range, high precision, reliability and good stability. It is that parameter measurement is accurate, the mine gas-concentration monitor. Key words: CPU; A/D converter circuit; Sensitive components; Alarm   目录  TOC \o 1-3 \h \z \u  HYPERLINK \l _Toc389480784 1.绪论  PAGEREF _Toc389480784 \h 1  HYPERLINK \l _Toc389480785 1.1 本课题的研究背景及意义  PAGEREF _Toc389480785 \h 1  HYPERLINK \l _Toc389480786 1.2国内外发展概况和研究方向  PAGEREF _Toc389480786 \h 1  HYPERLINK \l _Toc389480787 1.3课题主要研究内容与要求  PAGEREF _Toc389480787 \h 3