http://rdf.ncbi.nlm.nih.gov/pubchem/patent/EP-0922963-A3
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_a2bcaf91101a370a3d64e3190366357f |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/G01N27-028 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/G01R27-2623 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/G01N27-02 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/G01R27-26 |
| filingDate | 1998-10-16-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| inventor | http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_cbbe2059eaadb98e4ec85f46e85d1e9a http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_433978d16e8fd293fc06c6fbdefdf642 http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_e2c40ee4677df0932a6477d9f35bac23 |
| publicationDate | 2001-04-25-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | EP-0922963-A3 |
| titleOfInvention | Evaluation circuit for determining complex impedances, apparatus for measuring complex impedance and use of the apparatus |
| abstract | The present invention relates to an evaluation circuit for determinationncomplex impedances and on a device for measuring complexnImpedances with this evaluation circuit. The inventive device fornMeasurement of complex impedances can advantageously be used to analyze thenProperties of liquids, for the determination of the aging condition ofnLubricating oils, for moisture measurement in soil, for measuringnIon concentrations, for determining the water content in liquids withnlow dielectric constant, but especially for determining thenWater concentration in alcohols and vice versa, to determine thenWater content in oils and vice versa, for determining the water content innBrake fluid, for determining the composition of milk, especially fornDetermination of their fat content, to determine the time of hardening ofnConcrete and to investigate the contamination of the ground with oil or acidsnbe used. Especially if the device is a sensornSurface wave sensor contains can with the device according to the inventionnAcids and alkalis identified in water and their concentration determinationnbe made.n n n The evaluation circuit according to the invention for determining complex impedancesnincludes a voltage source for generating two AC signalsna first frequency, a current source from the first of the twonAC signals is driven and is suitablenGenerate alternating current signal, an amplification device, which over thenmeasuring impedance falling signal is supplied and which is suitablengenerate appropriate AC voltage signal, a device that is suitablenis the AC voltage signal output by the amplifying devicenthe second of the two AC signals from the voltage source,nwhich is phase-shifted by 0 ° or 90 °, to combinenthat from the respectively resulting first and second output signalsnReal part and the imaginary part of the impedance can be determined, a device fornProcessing the first and second output signals, the real part and thenImaginary part of the complex impedance is determined using the voltage sourcena frequency generator for generating digital signals, a 1: 2 frequency dividernand a device for generating two 90 ° phase-shiftednIncludes AC signals at the first frequency.n n n The evaluation circuit according to the invention enables a precise determination of the complex impedances even in the case of temperature fluctuations or different measuring frequencies without the need for complex devices for phase adjustment. |
| priorityDate | 1997-12-12-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 18.