# US 10,480,987 B2 · Calibrating an electromechanical fill-level measuring device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,480,987 B2 - Document ID: US10480987B2 - Status: Granted - Kind: B2 - Application number: 15/509,577 - Filed: 2015-08-19 - Published: 2017-09-07 - Granted: 2019-11-19 - Earliest claimed: 2014-09-11 - Assignees: Endress+Hauser SE+Co.KG - Applicants: Endress + Hauser GmbH + Co. KG - Inventors: Masashi Sano; Andreas Kaiser; Yoichi Kamei - Web page: https://patentgrep.com/patent/US10480987B2 ## CPC - G01F 25/20: of apparatus for measuring liquid level - G01F 23/0023: {with a probe suspended by a wire or thread (with floats G01F23/40)} - G01F: MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME ## Abstract An electromechanical fill-level measuring device comprising at least one displacement element, which is connected by means of a measurement wire windably at least with a measurement drum, at least one measuring shaft, with which the measurement drum is mechanically fixedly connected, wherein the shaft is held rotatably in at least one rotary bearing, at least one weight measuring system, which ascertains the effective weight of the displacement element and the measurement wire, and at least one servomotor, which is coupled with the measuring shaft and which rotates the measuring shaft corresponding to an ascertained weight measurement, so that an ascertaining of the relative movement of the measurement drum produced by a change of the liquid level to be measured is provided. The invention provides that a calibration mode of the weight measuring system of the electromechanical fill-level measuring device is provided, in which freely hanging displacement elements with defined mass are provided for ascertaining their weights on the measurement wire, after each change of the freely hanging displacement elements with defined mass a predefined rotational movement of the measurement drum is provided, and their ascertained weights are provided as a calibration values for the weight measuring system. ## Claims ### Claim 1 An electromechanical fill-level measuring device, comprising: at least one displacement element, which is connected by means of a measurement wire windably at least with a measurement drum; at least one measuring shaft, with which said measurement drum is mechanically fixedly connected, wherein the shaft is held rotatably in at least one rotary bearing; at least one weight measuring system, which ascertains the effective weight of said displacement element and said measurement wire; and a servomotor, which is coupled with said measuring shaft and which rotates said measuring shaft corresponding to an ascertained weight measurement, so that an ascertaining of the relative movement of said measurement drum produced by a change of the liquid level to be measured is provided, wherein: a calibration mode of said weight measuring system of the electromechanical fill-level measuring device is provided, in which a plurality of freely hanging displacement elements with defined mass, each having a different mass, are provided for ascertaining their weights on said measurement wire; and after each change of the freely hanging displacement elements with defined mass a predefined rotational movement of said measurement drum is provided, and their ascertained weights are provided as calibration values for the weight measuring system. ### Claim 2 (depends on 1) The electromechanical fill-level measuring device as claimed in claim 1, wherein: a displacement element with a defined first mass is provided on said measurement wire. ### Claim 3 (depends on 1) The electromechanical fill-level measuring device as claimed in claim 1, wherein: said freely hanging measurement wire without a displacement element hung thereon is provided as a second mass. ### Claim 4 (depends on 1) The electromechanical fill-level measuring device as claimed in claim 1, wherein: a displacement element with a defined second mass, which is different from the first mass, is provided on said measurement wire. ### Claim 5 (depends on 1) The electromechanical fill-level measuring device as claimed in claim 1, wherein: said predefined rotational movement of said measurement drum is provided in both rotational directions. ### Claim 6 (depends on 1) The electromechanical fill-level measuring device as claimed in claim 1, wherein: said predefined rotational movement of said measurement drum is provided with a defined angular velocity, a defined angular acceleration and/or a defined rotated distance. ### Claim 7 (depends on 1) The electromechanical fill-level measuring device as claimed in claim 1, wherein: an algorithm is provided at least in the calibration mode of said weight measuring system of the electromechanical fill-level measuring device for compensating and for calculating out of the current ascertaining of the weight the frictional force of the rotary bearing of said measuring shaft of said measurement drum. ### Claim 8 A method for calibrating the weight measuring system of an electromechanical fill-level measuring device, comprising: at least one displacement element, which is connected by means of a measurement wire windably at least with a measurement drum; at least one measuring shaft, with which said measurement drum is mechanically fixedly connected, wherein the shaft is held rotatably in at least one rotary bearing; at least one weight measuring system, which ascertains the effective weight of said displacement element and said measurement wire; and a servomotor, which is coupled with said measuring shaft and which rotates said measuring shaft corresponding to an ascertained weight measurement, so that an ascertaining of the relative movement of said measurement drum produced by a change of the liquid level to be measured is provided, wherein: a calibration mode of said weight measuring system of the electromechanical fill-level measuring device is provided, in which a plurality of freely hanging displacement elements with defined mass, each having a different mass, are provided for ascertaining their weights on said measurement wire; and after each change of the freely hanging displacement elements with defined mass a predefined rotational movement of said measurement drum is provided, and their ascertained weights are provided as calibration values for the weight measuring system; the method comprising the steps of: freely hanging displacement elements with defined mass for ascertaining their weight on the measurement wire; and after each change of the freely hanging displacement elements with predefined mass a predefined rotational movement of the measurement drum is performed, and the ascertained weights are used as calibration values for the weight measuring system. ### Claim 9 (depends on 8) The method for calibrating the weight measuring system of an electromechanical fill-level measuring device as claimed in claim 8, further comprising the step of: rotating the measurement drum by means of the predefined rotational movement in at least one or in both rotational directions with a defined angular velocity, a defined angular acceleration and/or a defined rotated distance. ### Claim 10 (depends on 9) The method for calibrating the weight measuring system of an electromechanical fill-level measuring device as claimed in claim 9, further comprising the steps of: using an algorithm at least in the calibration mode of the weight measuring system of the electromechanical fill-level measuring device for compensating the frictional force of the rotary bearing of the measuring shaft of the measurement drum; and calculating the frictional force out of the current ascertaining of the weight. ### Claim 11 (depends on 10) The method for calibrating the weight measuring system of an electromechanical fill-level measuring device as claimed in claim 10, wherein: the frictional force of the rotary bearing of the measuring shaft of the measurement drum is calculated out of the current ascertaining of the weight by the algorithm at least in the calibration mode of the weight measuring system of the electromechanical fill-level measuring device by ascertaining the weight difference in both rotational directions of the predefined rotational movement of the measurement drum and ascertaining the frictional force from this weight difference.