【作者】 刘庆刚；

【导师】 刘华毅；

【作者基本信息】 大连理工大学 ， 控制理论与控制工程， 2006， 硕士

【摘要】 现代生产技术的不断进步，对检测手段提出了越来越高的要求。气密性检测作为检测方式的一种，在保证产品质量方面起着越来越重要的作用。特别是在汽车行业，能否保证汽缸的气密性，直接影响着汽车的性能。随着测漏技术的发展，气体测漏仪的研究使测漏技术得到了更广泛的应用。传统的测漏方法操作不灵活，容易产生误判，而且不利于数据的存储分析。直压式气体测漏由于具有原理简单、成本较低、方便实用、干净无污染等优点，在气密性检测领域受到广泛的青睐。 本文设计了一种基于干式测漏法(直接压力测试法)结合89C58单片机技术的气体测漏仪。利用高精度A／D对压力和温度信号进行检测，通过LCD即时显示采集的压差数据，并提供了通讯接口，便于数据储存和分析。克服了传统方法易受主观因素的影响等缺点，实现了气密性检测的自动化。 论文首先阐述了课题的背景以及研究现状，对各种气密性检测方法进行了比较。给出了系统的总体工作模型和总体框图。并按模块化的设计思想分别对系统的硬件电路和软件程序进行了分析。硬件电路主要包括：压力信号采集电路、温度信号采集电路、键盘及显示电路、电磁阀驱动电路、电源电路和控制电路的设计和原理分析；软件设计主要包括：主程序的实现、键值的输出采集、液晶标准接口的读写、虚拟IIC总线的实现、零点漂移的克服以及自定义通讯协议的实现。同时，给出了各程序模块的设计思想和流程图。最后根据实验结果，对实验数据进行分析，得出了系统的精度。总结了本文的特点及不足，为快速性测量提供了现实依据。更多还原

【Abstract】 With the development of modern manufacture technique, the higher requirement of detecting method is put forward. Leakproofness detecting, as a method of detection, play a more and more important role in quality assurance of products. Especially in automobile industry, the leakproofness of cylinder influences the performance of auto car directly. For the development of detecting techniques, the research of leakage detector makes the detecting techniques in widely application. The traditional method of leakage detecting is inflexible, tending to cause mistakes, going against data storage and analysis. Because the leakage detecting by air pressure decay has some advantages such as simple principle, cheap, convenience and involution, it becomes more and more popular in the field of leakproofness detected.An air leak detector based on the technique of dry leakage detecting (air pressure decay) and 89C58 single chip microcomputer is designed in this paper. High accurate A/D is applied to detect pressure and temperature signal, LCD is used to display the pressure data, the communication interface is also provided to store and analyze data conveniently. The disadvantage of traditional leakage detecting method is conquered and the detecting automation is realized.First of all, the background and research actuality are advanced. Several kinds of leakproofness detecting methods are compared. The entire model and framework of the leakage detector are designed. Secondly, the hardware circuit and software program are analyzed separately according to the modularized design thought. The hardware circuits include: collection circuit of pressure signal, collection circuit of temperature signal, keyboard and LCD circuit, drive circuit of electromagnetism valve, power supply circuit and control circuit; the software functions include: main function, collection function of keyboard value, read-write function of LCD standard interface, function of virtual IIC bus, function of overcoming zero-point excursion and function of customized communication protocol. Meanwhile, the flow charts and design thoughts of the function modules are presented. At last, the precision of the system is gained by analyzing the experimental results. The characteristics and disadvantages are concluded and some valuable references to the researchers are given.更多还原