Patent US2575427A successfully refreshed from Google Patents.
US2575427A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Treatment of metalworking tools
Assignee: Individual
•
Filing: 1946-07-09
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Granted: 1951-11-20
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Expires: 1966-07-09
Abstract
No abstract record available.
Inventors
- 👤 Edward T Pavlock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 15:51
CPC Classifications
C; C23; C23C; C23C8/00; C23C8/06; C23C8/28; C23C8/30; C23C8/32; C23C8/40; C23C8/42; C23C8/48; C23C8/50
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
93 words
THE METHOF OF CASE HARDENING A STEEL TOOL WHICH COMPRISES PREHEATING THE TOOL TO A TEMPERTURE OF 800* F., HOLDING THE HEATED TOOL IMMERSED FOR A PERIOD OF ABOUT 50 MINUTES IN A NITRIDING BATH MAINTAINED AT A TEMPERATURE OF FROM 1025* TO 1050* F., CLEANING THE TOOL, PACKING THE TOOL IN GRANULATED CARBON, MAINTAINING THE PACKED TOOL FOR AT LEAST THREE HOURS IN AN ENCLOSED SPACE AT A TEMPERATURE NEAR TO, BUT BELOW, THE HARDNESS-DRAWING TEMPERATURE OF THE STEEL, AND ADMITTING WATER CONTINUOUSLY AT A REGULATED SLOW RATE TO SUCH ENCLOSED SPACE.
Claim 2
Dependent Claim
93 words
THE METHOF OF CASE HARDENING A STEEL TOOL WHICH COMPRISES PREHEATING THE TOOL TO A TEMPERTURE OF 800* F., HOLDING THE HEATED TOOL IMMERSED FOR A PERIOD OF ABOUT 50 MINUTES IN A NITRIDING BATH MAINTAINED AT A TEMPERATURE OF FROM 1025* TO 1050* F., CLEANING THE TOOL, PACKING THE TOOL IN GRANULATED CARBON, MAINTAINING THE PACKED TOOL FOR AT LEAST THREE HOURS IN AN ENCLOSED SPACE AT A TEMPERATURE NEAR TO, BUT BELOW, THE HARDNESS-DRAWING TEMPERATURE OF THE STEEL, AND ADMITTING WATER CONTINUOUSLY AT A REGULATED SLOW RATE TO SUCH ENCLOSED SPACE.
References Cited (Backward Citations)
US1774999A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-11-19 | 1955-05-21 | 1955-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-11-19 | 1959-05-21 | 1959-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-11-19 | 1963-05-21 | 1963-11-20 | $7700.00 | Window Closed / Lapsed |