초록 ▼

A method and apparatus for accurately measuring the level of liquid in a storage tank and graphically displaying that measurement. The system is particularly useful in vehicular fuel level measuring applications, since the system provides for sampling the level of the liquid over designated time per

A method and apparatus for accurately measuring the level of liquid in a storage tank and graphically displaying that measurement. The system is particularly useful in vehicular fuel level measuring applications, since the system provides for sampling the level of the liquid over designated time periods and comparing each sample reading with a previous sampling that is stored and presently controls the display. The graphical display is a unique bar graph comprised of groups of bar-like elements driven to provide a relative indication of the sensed and measured liquid level in contrast with the maximum level that may be sensed.

대표청구항 ▼

A liquid level measuring system comprising: means for containing said liquid within a predetermined volume; means within said containing means for sensing the level of said liquid therein and producing an analog signal indicative of said sensed level; said level sensing means contains an electrical

A liquid level measuring system comprising: means for containing said liquid within a predetermined volume; means within said containing means for sensing the level of said liquid therein and producing an analog signal indicative of said sensed level; said level sensing means contains an electrical means having electrical characteristics which vary over a predetermined range in correspondence with a volume range as determined by the maximum and minimum levels that may be sensed within said containing means; said electrical means is connected to receive a relatively stable electrical signal from a regulated power supply and to produce said analog signal having a value which varies over a predetermined range as a function of said sensed level, said electrical characteristic and said stable electrical signal; means connected to receive said analog signal and to convert said analog signal to a digital signal; means responsive to said digital signal for graphically displaying the sensed level of said liquid; and wherein said converting means contains means responsive to said analog signal for producing a cyclically varying signal having a frequency within a predetermined range of frequencies corresponding to said range of analog signal values; means for sequentially sampling and scaling said cyclically varying signal over sample periods of time that are each long enough to sample several cycles of said cyclically varying signal to produce digital values corresponding to said scaled sample signals; means for comparing the most recently produced digital value with the present digital value controlling said display means to verify the accuracy of said most recent digital value; means for adjusting said present digital value controlling said display when a predetermined number of respective most recently compared digital values are consistently different in value from said present digital value; and means for storing said present digital value for control of said display; and further wherein said display means depicts a bar graph comprised of a predetermined number of controlled display elements which when all are activated correspond to said maximum sensed level and whereby other levels are indicated by activating selected number of said display elements corresponding to controlling digital values from said scaling means.