JPS5473663A - Liquid level gauge - Google Patents

Abstract

PURPOSE: To enable float positions to be accurately detected by mounting an iron core provided with a plurality of narrow grooves or collars at an arbitrary interval in the axial direction to a float, floating the same in liquid surface and detecting the positions of said groove or collars with detection coils.

CONSTITUTION: This liquid level guage excites the primary winding 13 provided around an iron core 2 with alternating current of a fixed magnitude and measures the change in liquid level as the change in the output voltage induced in a secondary winding 14, wherein one exciting winding 24 and two detection windings 15 are provided around the iron core separately, in order to detect the positions of the grooves or collars provided to the iron core. By differentially connecting these two detection coils 15 or taking the difference of the two output voltages, pulse form output voltages are produced in a zero cross point extractor 22 as the liquid level passes the grooves or collars on the iron core 2. The use of said pulse form voltages and the output voltage produced in the secondary windings 14 enables the calibration of the liquid level gauge at the liquid level corresponding to the positions of the grooves or collars on the iron core to be performed.

COPYRIGHT: (C)1979,JPO&Japio