Measuring and testing – Liquid level or depth gauge
Patent
1996-01-16
1999-04-20
Dombroske, George M.
Measuring and testing
Liquid level or depth gauge
73290R, G01F 100
Patent
active
058958487
ABSTRACT:
A liquid level sensing apparatus, and related method, that utilizes a tuning fork assembly to detect the presence of not only a liquid or air at a particular location within a container, but also a solid material at that location. The tuning fork assembly includes an excitation transducer and a receiving transducer mechanically coupled to a pair of paddles that are exposed within the container, and a phase-locked loop control system applies an excitation signal to the excitation transducer having a frequency that is regulated to track the tuning fork's resonant frequency. A comparator compares that resonant frequency with a prescribed threshold, to determine whether the tuning fork assembly is disposed in air or a liquid. A failure of the phase-locked loop control system to lock the frequency of the excitation signal at any particular frequency indicates that the tuning fork assembly is over-damped and likely contacted by a solid material. Since the apparatus normally excites the tuning fork assembly at its resonant frequency, this allows the apparatus to be operated at reduced power levels, leading to improved efficiency.
REFERENCES:
patent: 3213438 (1965-10-01), Felice et al.
patent: 3625058 (1971-12-01), Endress et al.
patent: 3944994 (1976-03-01), Fanshawe
patent: 4213337 (1980-07-01), Langdon
patent: 4349881 (1982-09-01), November et al.
patent: 4383443 (1983-05-01), Langdon
patent: 4540981 (1985-09-01), Lapetina et al.
patent: 4594584 (1986-06-01), Pfeiffer et al.
patent: 5099454 (1992-03-01), Dieulesaint et al.
patent: 5191316 (1993-03-01), Dreyer
patent: 5223819 (1993-06-01), Marsh et al.
patent: 5247832 (1993-09-01), Umezawa et al.
patent: 5264831 (1993-11-01), Pfeiffer
patent: 5408168 (1995-04-01), Pfandler
Haynie Carl R.
McGeary William L.
Wilson Jeffrey D.
Biegel Ronald L.
Brueggemann James R.
Dombroske George M.
Flowline Inc.
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