Patent ID: 7081620

Claim:
An atmospheric pressure ionization mass spectrometer system comprising: an atmospheric pressure ion source having a spray probe for generating ions of a sample solution by spraying said sample solution from said spray probe into a space under the atmospheric pressure so as to ionize said sample solution sprayed in said space under said atmospheric pressure; a mass spectrometer for mass analyzing the ions in an evacuated space; a fine hollow tube provided through a partition wall between said atmospheric pressure ion source and said mass spectrometer and gaseous ions generated in said atmospheric pressure ion source being introduced through said fine tube into said mass spectrometer to be mass analyzed, wherein said fine tube comprises a first fine tube and a second fine tube which are different in diameter, said second fine tube being inserted in said first fine tube, a first space formed between said first fine tube and said second fine tube and a second space formed in said second fine tube respectively have respective inlet ends and respective outlet ends, and said respective inlet ends are arranged in said space under the atmospheric pressure of said atmospheric pressure ion source and said respective outlet ends are arranged in evacuated space of said mass spectrometer, said gaseous ions generated in said atmospheric pressure ion source and gas are fed into said inlet end of said second space, and sheath gas is fed into said inlet end of said first space, and said gaseous ions and said gas guided into said second space are coaxially emitted from said outlet end of said first space into a flow of said sheath gas flown with a sound velocity formed in a vacuum chamber evacuated.