基于LM567的实用型液位计的设计

为研制低成本、便携式的实用型液位计,采用了超声波检测技术,以超声波换能器作为传感器件,以廉价的集成锁相环音频解码器LM567作为回波的捕获器件,以单片机作为主控器。给出了硬件设计电路及单片机软件程序流程图,对液位计出现的测量误差也进行了详细的分析并提出了解决的方法。实验结果表明,设计可靠性高、使用方便并且采用干电池供电,可广泛应用于小型油库油箱的油位测量及锅炉水位检测等对液位计价格敏感的场合。

Design of a Practical Liquid-level Meter Based on LM567

For designing and developing a low cost and portable practical liquid-level meter, the ultrasonic technology is applied. The ultrasonic transducer is used as the sensing element, and the low-cost integrated DLL decoder LM567 functions as the device to capture the echo. The single chip computer is the main controller of the instrument. The hardware circuits and software flowchart in single chip computer are given. The measurement error of the level meter is analyzed in detail and related solution is proposed. The result of experiments indicates that the design is highly reliable and the instrument is easy to use. Because of the batteries powered the meter, it is suitable for level measurement for oil tank in small oil inventory or water level of boiler where the cost of instruments is sensitive factor.