US4087894A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacture of watch case
Assignee: SSIH Management Services SA
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Filing: 1976-11-29
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Granted: 1978-05-09
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Expires: 1996-11-29
Abstract
Abstract A watch case is made from an electrically conductive hard material compoud from aluminum oxide and titanium carbide by forming a blank by sintering the material, subjecting the blank to a heat treatment, spark machining the blank to its final form, and fine grinding and polishing the blank to a desired finish.
Inventors
- 👤 Gottfried Kuechli
- 👤 Paul Volgyi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 05:24
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/56; C04B35/5607; C04B35/5611; G; G04; G04B; G04B37/00; G04B37/22; Y; Y10; Y10S; Y10S29/00; Y10S29/025; Y10S29/026; Y10S29/031; Y10T; Y10T29/00; Y10T29/49; Y10T29/49579; Y10T29/49584
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
150 words
A process for the manufacture of a watch case from an electrically conductive hard material compounded from aluminum oxide and titanium carbide comprising the steps of: initially forming a blank by sintering the material under pressure and isostatic compacting at high temperature and gas pressure; subjecting the blank to a heat treatment including the steps of heating the blank under a vacuum ranging from 5 × 10 -4 to 5 × 10 -5 Torr during a period of 2 to 5 hours to a temperature ranging between 1100° C and 1400° C, maintaining the maximum temperature for a period of 2 to 6 hours, cooling under vacuum to a temperature of about 300° C, restoring ambient pressure and cooling at a rate of about 140° C/hour until ambient temperature is reached; spark machining the blank to its final form; and, fine grinding and polishing the blank to a desired finish.
Claim 2
Dependent Claim
150 words
A process for the manufacture of a watch case from an electrically conductive hard material compounded from aluminum oxide and titanium carbide comprising the steps of: initially forming a blank by sintering the material under pressure and isostatic compacting at high temperature and gas pressure; subjecting the blank to a heat treatment including the steps of heating the blank under a vacuum ranging from 5 × 10 -4 to 5 × 10 -5 Torr during a period of 2 to 5 hours to a temperature ranging between 1100° C and 1400° C, maintaining the maximum temperature for a period of 2 to 6 hours, cooling under vacuum to a temperature of about 300° C, restoring ambient pressure and cooling at a rate of about 140° C/hour until ambient temperature is reached; spark machining the blank to its final form; and, fine grinding and polishing the blank to a desired finish.
Claim 3
Dependent Claim
29 words
Process as set forth in claim 1 wherein the blank is initially formed to dimensions approximately equal to but somewhat greater than the overall dimensions of the finished product.
Claim 4
Dependent Claim
48 words
Process as set forth in claim 1 wherein the spark machining procedure includes a double time base composed of a first time base during which a current pulse of constant energy is applied to a machining electrode and a second time base comprising the interval between current pulses.
Claim 5
Dependent Claim
29 words
Process as set forth in claim 3 wherein the time bases are determined by the form of the machining electrode and the depth of the cut to be made.
References Cited (Backward Citations)
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US3679442A
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US3719479A
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US3998671A
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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) | 1981-05-08 | 1981-11-07 | 1982-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-08 | 1985-11-07 | 1986-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-08 | 1989-11-07 | 1990-05-09 | $7700.00 | Window Closed / Lapsed |