US4144451A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mass spectrometer
Assignee: Hitachi Ltd
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Filing: 1977-01-26
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Granted: 1979-03-13
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Expires: 1997-01-26
Abstract
Abstract Herein disclosed is an atmospheric pressure ionization mass spectrometer having a mediate pressure region, wherein a jet separator is incorporated for playing a double role of differential pumping and concentration of the electric field, and wherein a gas jetting aperture of the jet separator and another aperture for introducing a gas to an analyzing region of the spectrometer are made of a conductive body and are adapted to be kept at different electric potentials.
Inventors
- 👤 Hideki Kambara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:45
CPC Classifications
H; H01; H01J; H01J49/00; H01J49/02; H01J49/06; H01J49/067; B; B01; B01D; B01D59/00; B01D59/44; G; G01; G01N; G01N27/00; G01N27/62; G01N27/622; G01N27/623; H01J49/10; H01J49/14; H01J49/147; H01J49/16; H01J49/168
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
189 words
An atmospheric pressure ionization mass spectrometer comprising an ionization region maintained at about atmospheric pressure for ionizing a sample, a mediate pressure region maintained at about 0.1 to 10 Torr and a highly evacuated mass spectral region provided at its upstream side with auxiliary ionization means, a first partition wall separating said ionization region and said mediate pressure region for each other, at least a part of said partition wall being made of a conductive material to form a first electrode, a first fine aperture formed in said first electrode for effecting communication of said ionization region and said mediate pressure region with each other, a second partition wall separating said mediate pressure region and said mass spectral region from each other, at least a part of said second partition wall being formed of a conductive material to form a second electrode, a second fine aperture formed in said second electrode for effecting communication of said mediate pressure region and said mass spectral region with each other, said fine apertures in combination forming a jet separator, and means for applying an electric potential between said first and second electrodes.
Claim 2
Dependent Claim
189 words
An atmospheric pressure ionization mass spectrometer comprising an ionization region maintained at about atmospheric pressure for ionizing a sample, a mediate pressure region maintained at about 0.1 to 10 Torr and a highly evacuated mass spectral region provided at its upstream side with auxiliary ionization means, a first partition wall separating said ionization region and said mediate pressure region for each other, at least a part of said partition wall being made of a conductive material to form a first electrode, a first fine aperture formed in said first electrode for effecting communication of said ionization region and said mediate pressure region with each other, a second partition wall separating said mediate pressure region and said mass spectral region from each other, at least a part of said second partition wall being formed of a conductive material to form a second electrode, a second fine aperture formed in said second electrode for effecting communication of said mediate pressure region and said mass spectral region with each other, said fine apertures in combination forming a jet separator, and means for applying an electric potential between said first and second electrodes.
Claim 3
Dependent Claim
24 words
A mass spectrometer as claimed in claim 1, wherein the distance between said first and second fine apertures is about 0.5 to 20 mm.
Claim 4
Dependent Claim
17 words
A mass spectrometer as claimed in claim 2, wherein said distance is about 0.5 to 2 mm.
Claim 5
Dependent Claim
17 words
A mass spectrometer as claimed in claim 2, wherein said distance is about 2 to 20 mm.
Claim 6
Dependent Claim
17 words
A mass spectrometer as claimed in claim 4, wherein said distance is about 4 to 10 mm.
Claim 7
Dependent Claim
19 words
A mass spectrometer as claimed in claim 1, wherein said auxiliary ionization means is of the electron impact type.
Claim 8
Dependent Claim
18 words
A mass spectrometer as claimed in claim 1, wherein said ionization region is kept almost at atmospheric pressure.
Claim 9
Dependent Claim
21 words
A mass spectrometer as claimed in claim 1, wherein said mediate pressure region is kept at about 0.1 to 10 Torr.
Claim 10
Dependent Claim
22 words
A mass spectrometer as claimed in claim 1, wherein said ionization means in said ionization region is of the corona discharge type.
Claim 11
Dependent Claim
21 words
A mass spectrometer as claimed in claim 1, wherein said ionization means in said ionization region is of the radioisotope type.
Claim 12
Dependent Claim
22 words
A mass spectrometer as defined in claim 1, wherein said first and second fine apertures are 60 micrometers and 200 micrometers, respectively.
References Cited (Backward Citations)
US3920987A
Cited
US4023398A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-03-12 | 1982-09-11 | 1983-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-03-12 | 1986-09-11 | 1987-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-03-12 | 1990-09-11 | 1991-03-13 | $7700.00 | Window Closed / Lapsed |