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US4409712A
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Method for making a stylus having a graphite electrode
Assignee: Victor Company of Japan Ltd
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Filing: 1981-06-01
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Granted: 1983-10-18
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Expires: 2001-06-01
Abstract
Abstract A diamond body is heated in an environment of vacuum of inert gas containing a small amount of oxygen at a predetermined elevated temperature to allow the carbon atoms of the surface areas to form a layer of graphite on the diamond body. The diamond body is then lapped so that the graphite layer is shaped into the form of a stylus electrode.
Inventors
- 👤 Hideaki Takehara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:07
CPC Classifications
G; G11; G11B; G11B9/00; G11B9/06; G11B9/07; G11B9/075; G11B3/00; G11B3/44; G11B3/46; G11B3/48; Y; Y10; Y10T; Y10T29/00; Y10T29/43; Y10T29/435; Y10T29/49; Y10T29/49002; Y10T29/49117
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
70 words
A method for making a stylus having a graphite electrode comprising the steps of heating a body of diamond in a vacuum or inert gas environment containing a small amount of oxygen at a predetermined elevated temperature to cause carbon atoms of the diamond body to form a layer of graphite on the surface of said diamond body and shaping the graphite layer into an electrode of a desired width.
Claim 2
Independent Claim
70 words
A method for making a stylus having a graphite electrode comprising the steps of heating a body of diamond in a vacuum or inert gas environment containing a small amount of oxygen at a predetermined elevated temperature to cause carbon atoms of the diamond body to form a layer of graphite on the surface of said diamond body and shaping the graphite layer into an electrode of a desired width.
Claim 3
Dependent Claim
20 words
A method as claimed in claim 1, wherein said temperature is within a range from 1100° C. to 1500° C.
Claim 4
Dependent Claim
26 words
A method as claimed in claim 2, wherein said diamond body is heated at a pressure in a range from 3×10-2 Torr. to 200×10 -2 Torr.
Claim 5
Dependent Claim
21 words
A method as claimed in claim 3, wherein said diamond body is heated for a period up to approximately 9 hours.
Claim 6
Independent Claim
26 words
A method as claimed in any one of the preceding claims, wherein said oxygen has a partial pressure of (0.6)×10 -2 Torr. to 40×10 -2 Torr.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-10-17 | 1987-04-18 | 1987-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-17 | 1991-04-18 | 1991-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-17 | 1995-04-18 | 1995-10-18 | $7700.00 | Window Closed / Lapsed |