US3756682A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for outgassing permanent magnets
Assignee: Schlumberger Technology Corp
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Filing: 1970-08-03
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Granted: 1973-09-04
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Expires: 1990-08-03
Abstract
Abstract A permanent magnet is outgassed for use in a controlled atmosphere by heating a ferromagnetic material to a temperature at which an irreversible loss of remanence takes place, but below the temperature at which material effects substantially reduce or remove all remanence without further special heat treatment. Gases emitted from the heated surfaces of the magnet then are evacuated. Permanent magnetic properties are not destroyed by this heat treatment, and a magnetic field of substantial strength subsequently is produced by magnetizing the outgassed material. A specific embodiment of the invention enables a hollow cylindrical ion source magnet to be placed within the envelope of a small neutron generator to provide both a magnetic field and an ion source electrode. The assembled generator then is outgassed and sealed. Subsequent magnetization enables the electrode to produce the high intensity magnetic field needed for ion generation.
Inventors
- 👤 A Frentrop
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:59
CPC Classifications
H; H05; H05H; H05H3/00; H05H3/06; H01; H01J; H01J27/00; H01J27/02
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
73 words
A method for outgassing an ion source comprising the steps of assembling the ion source electrodes in the correct positions relative to each other, heating said ion source electrodes to approximately 600*C, evacuating gas emanating from said electrodes, cooling said ion source electrodes to substantially less than 600*C, and inducing a permanent magnetic field in at least one of said electrodes to produce a magnetic flux density of about 400 Gauss or more.
Claim 2
Independent Claim
73 words
A method for outgassing an ion source comprising the steps of assembling the ion source electrodes in the correct positions relative to each other, heating said ion source electrodes to approximately 600*C, evacuating gas emanating from said electrodes, cooling said ion source electrodes to substantially less than 600*C, and inducing a permanent magnetic field in at least one of said electrodes to produce a magnetic flux density of about 400 Gauss or more.
Claim 3
Dependent Claim
58 words
A method of assembling an ion source according to claim 1 wherein prior to the step of inducing a permanent field, said outgassed ion source is placed within a gas-tight enclosure, and the following steps are performed, heating said enclosure and said ion source to about 400*C, and evacuating gas released from said ion source and said enclosure.
Claim 4
Dependent Claim
27 words
A method of assembling an ion source according to claim 1 wherein said gas evacuating step comprises establishing a gas pressure of about 105 mm of hg.
Claim 5
Independent Claim
108 words
A method for outgassing an ion source comprising the steps of assembling the ion source electrodes in predetermined positions relative to each other, heating said ion source electrodes to a temperature which is sufficiently high to outgas said electrodes but which, at the same time, is less than the temperature at which the electrodes will undergo a change adversely affecting the magnetic properties of said electrodes, evacuating gas emanating from said electrodes, cooling said ion source electrodes to a substantially lower temperature, and inducing a permanent magnetic field in at least one of said electrodes to produce an average magnetic flux density of about 400 Gauss or More.
Claim 6
Independent Claim
108 words
A method for outgassing an ion source comprising the steps of assembling the ion source electrodes in predetermined positions relative to each other, heating said ion source electrodes to a temperature which is sufficiently high to outgas said electrodes but which, at the same time, is less than the temperature at which the electrodes will undergo a change adversely affecting the magnetic properties of said electrodes, evacuating gas emanating from said electrodes, cooling said ion source electrodes to a substantially lower temperature, and inducing a permanent magnetic field in at least one of said electrodes to produce an average magnetic flux density of about 400 Gauss or More.
Claim 7
Dependent Claim
23 words
The method of claim 4 wherein said gas evacuating step comprises establishing a gas pressure of about 105 mm of hg or less.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-03 | 1977-03-05 | 1977-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-03 | 1981-03-05 | 1981-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-03 | 1985-03-05 | 1985-09-04 | $7700.00 | Window Closed / Lapsed |