US3218683A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fabrication of exothermic, self-hardening mold
Assignee: Hitachi Ltd
•
Filing: 1962-08-24
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Granted: 1965-11-23
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Expires: 1982-08-24
Abstract
No abstract record available.
Inventors
- 👤 Nishiyama Takio
- 👤 Nangoh Tadao
- 👤 Sono Kiyomi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 04:21
CPC Classifications
B; B22; B22C; B22C1/00; B22C1/16; B22C1/18
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
77 words
A PROCESS FOR MANUFACTURING A SELF-HARDENING MOLD EXOTHERMICALLY, WHICH COMPRISES MIXING 4 TO 14 PARTS BY WEIGHT OF WATERGLASS AND 2 TO 4 PARTS OF A FINELY POWDERED SUBSTANCE, SELECTED FROM THE GROUP CONSISTING OF SILICON, CALCIUM SILICIDE, FERROSILICON, AND MIXTURES THEREOF, INTO 100 PARTS SILICA SAND, FORMING THE MIXTURE INTO A MOLD, PERMITTING THE MOLD TO HARDEN SOLELY BY REACTION OF THE SODIUM SILICATE WITH THE POWDERED SUBSTANCE AND IN THE ABSENCE OF EXTERNALLY APPLIED HEAT.
Claim 2
Dependent Claim
77 words
A PROCESS FOR MANUFACTURING A SELF-HARDENING MOLD EXOTHERMICALLY, WHICH COMPRISES MIXING 4 TO 14 PARTS BY WEIGHT OF WATERGLASS AND 2 TO 4 PARTS OF A FINELY POWDERED SUBSTANCE, SELECTED FROM THE GROUP CONSISTING OF SILICON, CALCIUM SILICIDE, FERROSILICON, AND MIXTURES THEREOF, INTO 100 PARTS SILICA SAND, FORMING THE MIXTURE INTO A MOLD, PERMITTING THE MOLD TO HARDEN SOLELY BY REACTION OF THE SODIUM SILICATE WITH THE POWDERED SUBSTANCE AND IN THE ABSENCE OF EXTERNALLY APPLIED HEAT.
References Cited (Backward Citations)
CH125482A
Cited
CH138776A
Cited
CH140720A
Cited
US1959179A
Cited
GB653587A
Cited
DE974520C
Cited
US2883723A
Cited
US3050796A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-11-22 | 1969-05-24 | 1969-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-11-22 | 1973-05-24 | 1973-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-11-22 | 1977-05-24 | 1977-11-23 | $7700.00 | Window Closed / Lapsed |