Paramagnetic gas analyzer using DC and AC magnetic fields
US4808921A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 20, 1987 |
| Grant date | Feb 28, 1989 |
| Priority date | — |
| Expiry date | May 20, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/74
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Paramagnetic gas analyzer comprising an electromagnet with an almost closed ferromagnetic circuit and a gap, including a measuring chamber with inlet and outlet lines for the gas to be analyzed as well as a gas of known magnetic susceptibility where devices are provided which measure the differential gas pressures in the respective lines by supplying an AC current to the electromagnetic. According to the present invention it is shown, how the power consumption can be considerably reduced. This object is achieved by superimposing a DC magnetic field generated by means of a permanent magnet onto the AC magnetic field. The amplitude of the measuring result depends on the product of the AC field and the DC field. If the DC field is strong enough, the AC field and thus the supplied power can be reduced accordingly. The latter also facilitates the filtering off of predetermined, undesirable signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.