Absolute liquid level sensor with digital refractive encoding

• Main Author: BURNS ALAN ALEXANDER
• Format: Patent
• Language: English
• Published: 28.02.2002
• Edition: 7
• Subjects: MEASURING; MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUIDLEVEL; METERING BY VOLUME; PHYSICS; TESTING

Multi-symbol refractive encoding of distance or level along a scale provides an advanced means for measuring liquid level or dissimilar-liquid interface level with a float. Distance or level information is encoded in the patterns of microfacets impressed in the scale. The microfacets divide and direct incident visible or infrared beams toward or away from detectors disposed in arrays. This approach provides significant reductions in the number of encoding tracks and of the size of the float, improved accuracy, fault detection, increased span, less friction, and easier installation. A slender rod can replace the wide encoding tape of prior designs. The rod can also be used to guide optical or acoustic signals efficiently from floats to the rod support and thus on to level indicating and recording devices. In addition, the rod support provides means for quick installation, signal coupling, and setting reference levels.