US3665245A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Quadrupole ionization gauge
Assignee: Research Corp
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Filing: 1969-10-27
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Granted: 1972-05-23
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Expires: 1989-10-27
Abstract
Abstract A non-magnetic ionization gauge or ion pump comprising a tube containing spaced cathodes at the same potential, with an intermediately positioned ring anode for setting up an oscillating stream of electrons that is focused or constrained within an axial path by an electric quadrupole lens arrangement which may be excited by the RF force. The quadrupole lenses create a field which is tuned firstly to lengthen and stabilize the path of the electrons thus causing greater ionization of the gas atoms in the tube, and also to expel the ions produced thereby, which ions are then collected by a cylindrical collector screen at a slightly negative potential surrounding the whole electrode structure. The collector current produced with this arrangement has been found to be approximately inversely proportional to the pressure within the range from 10 5 to 10 10 torr, so that collector currents of the order of microamperes can be obtained at very low pressure levels.
Inventors
- 👤 Helmut J Schwarz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 01:39
CPC Classifications
H; H01; H01J; H01J41/00; H01J41/12; H01J41/14; H01J41/02; H01J41/06
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
70 words
A non-magnetic ionization device comprising: a. means for producing an oscillating stream of electrons; b. means for producing an electric field for focusing and confining said stream in continuous oscillation within a substantially restricted path and for expelling from said path ions resulting from the collision of said electrons with atoms in said path; and c. means disposed about said field-producing means for collecting the ions expelled from said path.
Claim 2
Dependent Claim
70 words
A non-magnetic ionization device comprising: a. means for producing an oscillating stream of electrons; b. means for producing an electric field for focusing and confining said stream in continuous oscillation within a substantially restricted path and for expelling from said path ions resulting from the collision of said electrons with atoms in said path; and c. means disposed about said field-producing means for collecting the ions expelled from said path.
Claim 3
Dependent Claim
17 words
A device as in claim 1 wherein said electric field-producing means comprises a set of quadrupole electrodes.
Claim 4
Dependent Claim
53 words
A device as in claim 1, wherein said stream-producing means comprises spaced cathodes, and an anode disposed between and at a positive potential relative to said cathodes and wherein said electric field-producing means comprises quadrupole electrodes arranged about an axis defined by said stream and at substantially the same potential as said anode.
Claim 5
Dependent Claim
44 words
A device as in claim 3 wherein said quadrupole electrodes are supplied with a high frequency voltage Uocos omega t for creating an electric field whose respective components along the Y and Z axes through the opposite pairs of electrodes are of the form
Claim 6
Dependent Claim
25 words
A device as in claim 3 wherein said ion collecting means comprises one of said cathodes at a negative potential relative to the other cathode.
Claim 7
Dependent Claim
27 words
A device as in claim 3 wherein said ion collecting means comprises an annular electrode disposed about said quadrupole electrodes and at a negative potential relative thereto.
Claim 8
Dependent Claim
23 words
A device as in claim 3 wherein one of said cathodes comprises a metallic electrode heated to produce a vapor for getter action.
Claim 9
Dependent Claim
125 words
An ionization gauge comprising: a. two spaced electrodes; b. a third electrode disposed between said spaced electrodes and at a positive potential relative to each and having an opening therein to permit a stream of electrons to follow an oscillating path between said spaced electrodes for ionizing atoms in said path; wherein the improvement comprises: c. quadrupole electrode means disposed about said path at approximately the sAme potential as said third electrode and having a high frequency voltage impressed thereon for confining said electron stream within said path and expelling ions resulting from the ionization of atoms in said path; and d. a cylindrical electrode surrounding said quadrupole electrode means and at a negative potential relative thereto for collecting the ions expelled from said path.
Claim 10
Dependent Claim
125 words
An ionization gauge comprising: a. two spaced electrodes; b. a third electrode disposed between said spaced electrodes and at a positive potential relative to each and having an opening therein to permit a stream of electrons to follow an oscillating path between said spaced electrodes for ionizing atoms in said path; wherein the improvement comprises: c. quadrupole electrode means disposed about said path at approximately the sAme potential as said third electrode and having a high frequency voltage impressed thereon for confining said electron stream within said path and expelling ions resulting from the ionization of atoms in said path; and d. a cylindrical electrode surrounding said quadrupole electrode means and at a negative potential relative thereto for collecting the ions expelled from said path.
Claim 11
Dependent Claim
113 words
An ion pump comprising: a. a first heated cathode for emitting a supply of electrons; b. a second heated cathode for producing a vapor for gettering action; c. an anode disposed between said first and second cathodes and at a positive potential relative to each; d. a set of quadrupole electrodes disposed about an axis defined by said cathodes and said anode and at substantially the same potential as said anode and having a high frequency voltage impressed thereon for setting up an electric field tending to focus said supply of electrons along a confined oscillating path and to expel any ions in said path; and e. means for collecting said expelled ions.
Claim 12
Dependent Claim
113 words
An ion pump comprising: a. a first heated cathode for emitting a supply of electrons; b. a second heated cathode for producing a vapor for gettering action; c. an anode disposed between said first and second cathodes and at a positive potential relative to each; d. a set of quadrupole electrodes disposed about an axis defined by said cathodes and said anode and at substantially the same potential as said anode and having a high frequency voltage impressed thereon for setting up an electric field tending to focus said supply of electrons along a confined oscillating path and to expel any ions in said path; and e. means for collecting said expelled ions.
Claim 13
Dependent Claim
38 words
An ion pump as in claim 10, wherein the high frequency voltage has a frequency of 1.08 X 105ro 1Uo1/2 Hertz ro being the internal quadrupole electrode radius in meters and Uo being the maximum voltage in volts.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-23 | 1975-11-22 | 1976-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-23 | 1979-11-22 | 1980-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-23 | 1983-11-22 | 1984-05-23 | $7700.00 | Window Closed / Lapsed |