Patent · US Expired

Mass spectrometer

US6147346A · kind A · utility

1Cited by
2References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 17, 1998
Grant dateNov 14, 2000
Priority date
Expiry dateSep 17, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J49/10
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A mass spectrometer with an ionizing chamber in which either of an NCI ion source for producing negative ions and a PCI ion source for producing positive ions is placed. The NCI ion source has a first gas inlet and a second gas inlet, while the PCI ion source has only one gas inlet. In the wall of the ionizing chamber are provided a sample gas inlet and a reaction gas inlet. At an end of the sample gas inlet inside of the ionizing chamber is provided a splitter having a first branch and a second branch. When the NCI ion source is placed in the ionizing chamber, the first gas inlet is connected to the first branch, the second gas inlet is connected to the reaction gas inlet inside of the ionizing chamber, and the second branch is left unconnected inside of the ionizing chamber. By adequately adjusting the flow resistances of the first and second branches, a desired portion of the reference gas from the sample gas source can be supplied to the NCI ion source when a calibration is performed. After the calibration is finished, the residual gas and ions in the NCI ion source are evacuated to the ionizing chamber through the first gas inlet, first branch and second branch. When the PCI i…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.