Liquid surface level detector

Abstract

Abstract PURPOSE:To secure stabilization against changes in the voltag and temperature by detecting a liquid level from a relative value of the output of a plurality of photo detectors with a light reflectd from a float after the detectors different in the directivity are provided at one end of a long cylinder with a light emitting element. CONSTITUTION:A light emitting diode 4 and two photo transistors 6 and 7 different in the directivity are arranged at the upper end of a long cylinder 1 in which a float 3 is placed free corresponding to the top of a regular triangle. A light from the light emitting diode 4 is reflected on the top surface of the float 3 and detected with the photo transistors 6 and 7 to detect the level of a liquid surface A. Therefore, the distance to the float 3 can be determined accurately by taking a relative value between the variation factor of the output of a photo detector narrow in the directivity and that of the output of a photo detector broad in the directivity and hence, a detector can be obtained hardly affected by changes in the intensity of light from any light emitting element.

Inventors

• 👤 Yasukuni Yamane
• 👤 Nobutoshi Gako
• 👤 Hidetaka Shintaku
• 👤 Kazutada Azuma
• 👤 Chuji Suzuki

Bibliographic Details