EP 0985139 A1 20000315 - DIFFERENTIAL PRESSURE TRANSDUCER
Title (en)
DIFFERENTIAL PRESSURE TRANSDUCER
Title (de)
DIFFERENTIELLER DRUCKMESSUMFORMER
Title (fr)
TRANSDUCTEUR DE PRESSION DIFFERENTIELLE
Publication
Application
Priority
- EP 99910072 A 19990331
- CH 9900136 W 19990331
- EP 98810282 A 19980401
Abstract (en)
[origin: EP0947815A1] A micro-engineered differential pressure transducer (100) with a housing enclosing a measurement chamber having a membrane (150) which includes a magnetic layer and divides the chamber into a first pressure sensing cavity (111) and a second pressure sensing cavity (112). On either side of , and spaced apart from, the membrane assembly are positioned flat coils (121;122), each connected into an external electrical measurement circuit. A relative change in pressure between the two sensing cavities effects deflection of the membrane assembly from its rest position causing electrical currents, of proportional magnitudes to the deflection and the pressure difference, to flow in the coils. The external circuit may contain a differential oscillator. Corrosion resistant membrane materials include: polytetrafluorethylene, ethylenetetrafluorethylene, polyethylenecotrifluorethylene, perfluoralkoxypolymers, polyvinylidene fluoride, and copolymers of tetrafluoromethylene / hexa fluoropropylene and polyethylene, various polyesters, and stainless steel. The magnetic elements may be soft ferromagnetic type e.g. amorphous metal, nickel-iron alloys, silicon iron, iron, ferrite, and silicon-iron-aluminium; or, hard material e.g. aluminium-nickel, aluminium-nickel-cobalt, rare earth, neodymium-iron-boron, neodymium-iron-cobalt, or hard ferrite, etc. A typical flat coil has a diameter of approx. 11 mm, and is wound from 50 microns diameter, gold plated wire.
IPC 1-7
IPC 8 full level
G01L 9/00 (2006.01); G01L 13/06 (2006.01)
CPC (source: EP US)
G01L 9/007 (2013.01 - EP US)
Citation (search report)
See references of WO 9950633A1
Designated contracting state (EPC)
AT BE CH DE DK FR GB IE IT LI
DOCDB simple family (publication)
EP 0947815 A1 19991006; CA 2291103 A1 19991007; EP 0985139 A1 20000315; JP 2002501621 A 20020115; US 6484586 B1 20021126; WO 9950633 A1 19991007
DOCDB simple family (application)
EP 98810282 A 19980401; CA 2291103 A 19990331; CH 9900136 W 19990331; EP 99910072 A 19990331; JP 54868099 A 19990331; US 42492400 A 20000214