Global patent index - EP 0986739 A1

EP 0986739 A1 2000-03-22 - METHOD FOR MEASURING A MASS FLOW RATE AND CORRESPONDING DETECTOR

Title (en)

METHOD FOR MEASURING A MASS FLOW RATE AND CORRESPONDING DETECTOR

Title (de)

VERFAHREN ZUM MASSEDURCHFLUSS-MESSEN UND ENTSPRECHENDE AUFNEHMER

Title (fr)

PROCEDE DE MESURE DE DEBIT-MASSE ET CAPTEUR CORRESPONDANT

Publication

EP 0986739 A1 (DE)

Application

EP 99917901 A

Priority

  • EP 99917901 A
  • EP 9902134 W
  • EP 98106146 A

Abstract (en)

[origin: WO9951946A1] The invention relates to a method which applies the clamp-on construction principle to coriolis-type mass flowmeters and detectors. A first and a second decoupling body (4, 5; 4', 5') with identical masses are fixed on a pipeline or a meter tube (1', 10, 10', 10'') at a distance L away from each other in order to define the segment of tube (11; 11'; 11'') which will form the measuring section. The masses of said decoupling bodies are significantly greater than the mass of the tube segment. For two meter tubes, clamping bodies (111, 112; 111', 112') are used. An exciter arrangement (12) is mounted in the centre of the tube segment. This exciter arrangement causes the tube segment to vibrate, the vibrations being of a third vibration mode with a frequency (f) of between 500 Hz and 1000 Hz. The distance L is calculated according to the following formula: L = 5,5 . 2<1/2> . (2 pi f)<-1/2> . {E(r<4>a-r<4>i)/(dM + dF)}<-1/4>, (ra,ri = the outer or inner diameter of the tube segment, E = the elasticity modulus of the tube segment, dM = the density of the material of the tube segment multiplied by its cross-sectional area, dF = the average density of the fluid multiplied by the cross-sectional area of the clear width of the tube segment). Two sensor elements (13, 14) are fixed on the tube segment at the point where a deformation of the tube segment resulting from the interference from the pipeline during excitation in the third vibration mode has a first or a second zero point.

IPC 1-7 (main, further and additional classification)

G01F 1/84

IPC 8 full level (invention and additional information)

G01F 1/84 (2006.01)

CPC (invention and additional information)

G01F 1/8409 (2013.01); G01F 1/8413 (2013.01); G01F 1/8418 (2013.01); G01F 1/8422 (2013.01); G01F 1/849 (2013.01); G01F 1/8495 (2013.01)

Citation (search report)

See references of WO 9951946A1

Designated contracting state (EPC)

CH DE DK ES FR GB IT LI NL

EPO simple patent family

WO 9951946 A1 19991014; CN 1192214 C 20050309; CN 1263596 A 20000816; EP 0986739 A1 20000322; JP 2000513454 A 20001010; JP 3188483 B2 20010716; US 6360614 B1 20020326

INPADOC legal status

2010-03-24 [18D] DEEMED TO BE WITHDRAWN

- Ref Legal Event Code: 18D

- Effective date: 20091001

2008-02-13 [17Q] FIRST EXAMINATION REPORT

- Ref Legal Event Code: 17Q

- Effective date: 20080111

2000-08-23 [17P] REQUEST FOR EXAMINATION FILED

- Ref Legal Event Code: 17P

- Effective date: 20000624

2000-03-22 [AK] DESIGNATED CONTRACTING STATES:

- Ref Legal Event Code: AK

- Designated State(s): CH DE DK ES FR GB IT LI NL