【作者】 张海霞；

【导师】 滕召胜；

【作者基本信息】 湖南大学 ， 测试计量技术及仪器， 2005， 硕士

【摘要】 现代社会的发展,对称重技术提出了更高的要求。目前,台式电子秤在商业贸易中的使用已相当普遍,但存在较大的局限性:体积大、成本高、需要工频交流电源供应、携带不便、应用场所受到制约。现有的便携秤为杆秤或以弹簧压缩、拉伸变形来实现计量的弹簧秤,居民用户使用的是国家已经明令淘汰的杆秤。多年来,人们一直期待测量准确、携带方便、价格低廉的便携式电子秤投放市场。 本文设计了一种便携式电子秤,论述了仪器的工作原理,介绍了仪器的误差来源与误差分配,给出了仪器电路设计与软件流程,探讨了仪器的工程设计技术。针对电容式称重传感器非线性影响大的问题,提出并建立了电容式称重传感器的非线性影响模型与校正模型,为便携式电子秤的低成本准确称量奠定了理论基础。 便携式电子秤主要由电源、称重传感器、单片机、键盘/开关、LCD显示器等部分构成。主要技术指标为:称量范围0～10kg;分度值0.01kg;精度等级Ⅲ级;电源DC 1.5V。仪器的技术指标参考了目前国内市场上使用最多、国内外产量最大的电子衡器的技术指标,其合理性无疑加大了产品投放市场后的竞争能力。仪器主要功能有自检、去皮、计价、累计、单价设定、过载报警和欠压提示等。仪器若不进行称量操作,5分钟后自动进入休眠模式,降低电源消耗。 新型便携式电子秤体积小、计量准确、携带方便、操作简单、称量速度快,并集质量称量功能与价格计算功能于一体,能够满足商业贸易和居民家庭的使用需求,具有广阔的应用前景。更多还原

【Abstract】 The development of the modern society has put forward higher request on weighing technology. The desk-top electronic scales have been great application in commercial trade, but they have many shortcomings such as large volume, high cost, AC supply power and not covenience to carry, so they are restricted to use. The usual portable scales are lever scales which are mostly used by residents, and spring balance which measure through compression or drawing of spring. They are being rejected for their big measuring errors. People have been expecting cheap portable electronic scales which can measure accurately and be carried conveniently for many years.This thesis designs new-type portable electronic scales. It discusses the instrumental working principle, and introduces its error sources and how to distribute the error. And, the instrumental circuit, software-flow-chart and engineering designing technology are presented. Because capacitance weighing sensor is of bad non-linearity, the author put forward and set up a maths model to revise non-linearity, which establishes the theory basis for the instrument to measure accurately and be low-cost.The portable electronic scales consist of power, weighing sensor, microchip, keyboard/switch, LCD and etc. Its technical indictors include 10kg maximal measuring range, 10g division value, III precision, 1.5V work voltage. Its technical indictors refer to the indictors of the electriconic measuring tools of most popularity in the markets and of large output at home and board, so the instrument is strengthened the competitive power after putting on markets. It possesses many intelligent functions, such as shelling, lack-of-power display, overload alarm, unit price enactement, accumulation computation, self-calibrating and etc. It can "sleep" automatically in five minutes if it is not measuring.New-type portable electronic scales can measure mass rapidly and accurately and communicate value. Furthermore, it is small, simply structured, easy to operate and convenient to carry. The instrument is able to meet the needs of commercial trade and residents, so its application has a bright future.更多还原