Density measuring device

US10598534B2 · kind B2 · utility

Assignee

• Endress+Hauser Flowtec AG · CH

Inventors

• Christof Huber · Bern, CH
• Vivek Kumar · Troy, US
• Philipp Montsko · Lindenberg im Allgäu, DE
• Tobias Schwer · Kirchzarten, DE

Key dates

• Filing date: Nov 3, 2014
• Grant date: Mar 24, 2020
• Expiry date: Feb 17, 2035

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N2009/006
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The density measuring device serves for measuring density, ρ, of a flowable medium and comprises a measuring device electronics (ME) as well as a measuring transducer (MT) electrically connected therewith. The measuring transducer includes a measuring tube (10), an oscillation exciter (41) for exciting and maintaining oscillations and an oscillation sensor (51) for registering oscillations of the at least one measuring tube. The measuring device electronics is adapted by means of an oscillation measurement signal (s1) as well as an exciter signal (e1) to adjust a drive force effecting wanted oscillations (namely oscillations with a predetermined wanted frequency, fN) of the measuring tube. The drive force is adjusted in such a manner that during a predetermined phase control interval a phase shift angle, φN, by which a velocity response, VN, of the measuring tube Is phase shifted relative to a wanted force component, FN, of the drive force, is less than −20° and greater than −80°, and/or the wanted frequency has a frequency value, which corresponds to greater than 1.00001 times, equally as well less than 1.001 times, a frequency value of an instantaneous resonant frequency of the m…