US3821093A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of fabrication of a probe for a hygrometer
Assignee: Commissariat à l'Énergie Atomique et Aux Énergies Alternatives
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Filing: 1972-06-16
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Granted: 1974-06-28
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Expires: 1992-06-16
Abstract
Abstract The hygrometer probe is fabricated in successive steps which consist in forming a probe body having an aluminum base, in subjecting the probe body to a surface treatment comprising at least one mechanical polishing operation and one electrochemical polishing operation, in carrying out anodic oxidation of the probe body and in subjecting the film-layer of alumina thus formed to a hygrothermal treatment, in depositing a metallic film-layer by vacuum evaporation, and in placing the necessary connections on the probe.
Inventors
- 👤 J Violet
- 👤 G Carron
- 👤 G Pleyber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:08
CPC Classifications
C; C25; C25F; C25F3/00; C25F3/16; C25F3/18; C25F3/20; G; G01; G01N; G01N27/00; G01N27/02; G01N27/04; G01N27/12; G01N27/121; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49826; Y10T29/49881; Y10T29/49885
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
18 words
A method according to claim 1, wherein the electro-chemical polishing operation is followed by a chemical polishing operation.
Claim 2
Dependent Claim
53 words
A method according to claim 1, wherein the electrochemical polishing of the probe body is carried out in a bath comprising a mixture of orthophosphoric acid, chromic anhydride and sulphuric acid, said mixture being brought to an operating temperature corresponding to a viscosity of 5 to 7 centipoises at 4 to 5 volts.
Claim 3
Dependent Claim
46 words
A method according to claim 3, wherein the mixture constituting the electrochemical polishing bath has a composition, for approximately 380 liters of said mixture, of approximately 357 liters of 85 % orthophosphoric acid, 45 kg of chromic anhydride and 21 liters of 66* Be. sulphuric acid.
Claim 4
Dependent Claim
46 words
A method according to claim 2, wherein the chemical polishing of the probe body is carried out in a bath constituted by a mixture of phosphoric acid, chromic anhydride and water for effecting the dissolution of the alumina which has formed during the electrochemical polishing operation.
Claim 5
Dependent Claim
44 words
A method according to claim 5, wherein the mixture of the chemical polishing bath has a composition, for 1000 cm3 of said mixture, of 35 cm3 of phosphoric acid, 20 grams of chromic anhydride and water in a sufficient quantity to make-up 1000 cm3.
Claim 6
Dependent Claim
42 words
A method according to claim 5, wherein the probe body is immersed in the chemical polishing bath for a period of 5 to 10 minutes, said bath being brought to and maintained at a temperature of approximately 80* C during this operation.
Claim 7
Dependent Claim
71 words
A method according to claim 1, wherein the anodic oxidation of the probe body is carried out in a bath of 30 wt % of sulphuric acid with an alternating current of 2.5 to 3.3 A/dm3 or a direct current of 1.2 to 1.6 A/dm3, the bath being at a temperature of approximately 30* C and the probe body being immersed in said bath for a period of approximately 10 minutes.
Claim 8
Dependent Claim
40 words
A method according to claim 1, wherein the metallic film-layer which is deposited by vacuum evaporation is of metal such as NiCr or Cr which has good adherence on the alumina and has a thickness of 200 to 300 A.
Claim 9
Dependent Claim
15 words
A method according to claim 1, wherein the probe body is formed of polycrystalline aluminum.
Claim 10
Dependent Claim
16 words
A method according to claim 1, wherein the probe body is formed of pure monocrystalline aluminum.
Claim 11
Dependent Claim
17 words
A method according to claim 1, wherein the probe body is formed of a monocrystalline aluminum alloy.
Claim 12
Dependent Claim
19 words
A method according to claim 12, wherein the probe body is formed of an alloy of aluminum with titanium.
Claim 13
Dependent Claim
53 words
A method according to claim 1, wherein the connection corresponding to the metallic film-layer is formed by the superposition of a metallic film having a thickness greater than 4000 A at one extremity which has previously been coated with an insulating resin, said metallic film-layer being clamped by means of a metal ring.
Claim 14
Dependent Claim
26 words
A method according to claim 1, wherein the connection corresponding to the metallic film-layer is constituted by a copper contact having a thickness of 4000 A.
Claim 15
Dependent Claim
25 words
A method according to claim 1, wHerein one of the probe connections is constituted by a metal rod which is screwed into the probe body.
Claim 16
Dependent Claim
25 words
A method according to claim 1, wherein one of the probe connections is constituted by a metal rod which is riveted to the probe body.
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) | 1977-06-27 | 1977-12-27 | 1978-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-27 | 1981-12-27 | 1982-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-27 | 1985-12-27 | 1986-06-28 | $7700.00 | Window Closed / Lapsed |