室内煤气和天然气泄漏报警器-毕业论文(设计).docVIP

PAGE PAGE 19 摘要：随着天然气和煤的大量使用，每一座居民大楼都被天然气所“笼罩”。天 然气的普及给公共生活带来了方便，减少了城市的污染，提高了生活质量和效率，但是同时天然气也是潜在的“危险品”，一旦发生大面积泄漏，处置不及时就可能引发大爆炸，给居民的生命财产安全带来巨大的威胁。面对天然气泄漏造成的种种事故威胁，我们需要一个解决办法。使用天然气报警器是对付燃气无形杀手的重要手段之一。 本文以气敏传感器和单片机技术为核心设计的气体报警器可实现声光报警功能，是一种结果简单、性能稳定、使用方便、价格低廉、智能化的气体报警器，具有一定的使用价值。 其中选用MQ-7传感器实现对气体的检测，具有灵敏度高、响应块、抗干扰能力强等优点，而且价格低廉，使用寿命长。其与LM358连接，将气体信号转换成单片机可识别的数字信号，经AT89C51单片机处理，并对处理后的数据进行分析，是否大于或等于某个预设值（也就是报警线），如果大于则会自动启动报警电路发生报警声音，反之则为正常状态。同时，该报警器还有温度检测功能。 关键词：传感器 报警器 单片机 Abstract: With the wide use of natural gas and coal, each a residential towers were gas “enveloped”. The popularity of natural gas brought convenient to public life, reduce the city’s pollution and improve the life quality and efficiency. But at the same time, natural gas is also potential “dangerous”, once produce large leak, disposal not timely could trigger, it will be a big bang to people’s life and property safety . Facing all kinds of accidents caused by the gas leak, we need a solution. Use of natural gas alarm is one of important means deal with gas invisible killer. This papers using the gas sensors and single chip microcomputer as the core design can realize the gas alarm sound-light function, It is a kind of simple structure, stable performance, easy to use, inexpensive and intelligent gas alarm and it also has certain practical value. Among them, the MQ-7 of gas detection sensor has a high sensitivity, fast response, strong anti-jamming capability etc, and the price is low, service life long. LM358 connected with the gas signal, convert the gas signal to the digital signal that microcontroller can identify and processing. Be processed and analysis by AT89C51, compare the result value whether is equal to or greater than the default value (that is ,the alarm limit), if it is greater than the default value, it will automatically start alarm circuit warning voice, conversely for normal state. At the same time ,the alarm has temperature testing function. Key