WATER LEVEL MEASUREMENT DEVICE AND WATER LEVEL MEASUREMENT METHOD

• Main Authors: NEMOTO KAZUMASA, MORIKAWA ROKURO
• Format: Patent
• Language: English
• Published: 16.05.2013
• Subjects: MEASURING; MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUIDLEVEL; METERING BY VOLUME; PHYSICS; TESTING

PROBLEM TO BE SOLVED: To provide a water level measurement device which achieves accurate measurement results free of influence from temperature variation and atmospheric pressure fluctuation, without addition of special hardware and software.SOLUTION: A water level measurement device includes an airtight housing having an atmospheric pressure introduction part which introduces the atmospheric pressure and a hydraulic pressure introduction part which introduces the hydraulic pressure at the water level of a sampling point. The atmospheric pressure introduction part is provided with a first pressure receiving element which expands or contracts in response to the change in the introduced atmospheric pressure. The hydraulic introduction part is provided with a second pressure receiving element which expands or contracts in response to the change in the introduced hydraulic pressure. The first pressure receiving element is provided with an FBG for atmospheric pressure which detects the expansion or contraction of the pressure receiving element, while the second pressure receiving element is provided with an FBG for hydraulic pressure which detects the expansion or contraction of the pressure receiving element. The FBG for atmospheric pressure and the FBG for hydraulic pressure are connected through an optical fiber. An optical signal is applied from one end of the optical fiber so as to obtain a reflected optical signal, in which the water level is calculated based on the change in wavelength corresponding to the FBG for atmospheric pressure and the change in wavelength of the FBG for hydraulic pressure.