Patent US3939897A successfully refreshed from Google Patents.
US3939897A
Expired / Lapsed
US
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Method for producing heat-insulating casting
Assignee: Toyota Motor Corp
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Filing: 1973-07-10
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Granted: 1976-02-24
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Expires: 1993-07-10
Abstract
Abstract A method for producing a heat-insulating casting characterized by placing a flexible ceramic semifinished product having a smooth surface, a modulus of elasticity of 200-5000 Kg/mm 2 , a bending strength of 8-200 Kg/cm 2 , and a wall-thickness less than 1/4 of the inside diameter, inside a casting mold, and casting molten metal so as to enclose the ceramic semifinished product.
Inventors
- 👤 Yasuhisa Kaneko
- 👤 Yasuhiko Komatsu
- 👤 Yoshihiro Hibino
- 👤 Yasuo Okada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 04:03
CPC Classifications
F; F02; F02F; F02F1/00; F02F1/24; F02F1/26; F02F1/36; F02F1/38; B; B22; B22D; B22D19/00; B22D19/0009; B22D19/0018
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
64 words
A method for manufacturing heat-insulating castings comprising the steps of: setting a flexible semifinished ceramic product, having a smooth surface, an elastic modulus of 200 to 5,000 kg/mm 2 , a bending strength of 8 to 200 kg/cm 2 , and a wall-thickness less than 1/4 of its inside diameter, inside a casting mold and casting molten metal to enclose the ceramic semifinished product.
Claim 2
Independent Claim
64 words
A method for manufacturing heat-insulating castings comprising the steps of: setting a flexible semifinished ceramic product, having a smooth surface, an elastic modulus of 200 to 5,000 kg/mm 2 , a bending strength of 8 to 200 kg/cm 2 , and a wall-thickness less than 1/4 of its inside diameter, inside a casting mold and casting molten metal to enclose the ceramic semifinished product.
Claim 3
Dependent Claim
59 words
A method for manufacturing heat-insulating castings according to claim 1, comprising the further steps of: preparing a slip-like substance of ceramic material; pouring said ceramic material into a shaping mold; curing said ceramic material in said shaping mold; removing said ceramic material from said shaping mold; and drying said material under heated conditions to produce said semi-finished ceramic product.
Claim 4
Dependent Claim
47 words
The method according to claim 2 wherein said ceramic material is cured in said shaping mold for a period of between approximately 4 and 24 hours and said drying step includes heating said material for a preset time at a temperature of between approximately 70° and 200°C.
Claim 5
Dependent Claim
52 words
The method according to claim 3, wherein said drying step includes heating said material at said temperature of between approximately 70° and 200°C for approximately 24 hours and thereafter further heating said material for a period of between approximately 24 and 48 hours at a temperature of between approximately 850° and 1,550°C.
Claim 6
Dependent Claim
36 words
The method according to claim 4, wherein in said further heating step said ceramic material is heated to at least the casting temperature of said molten metal prior to casting said metal in said casting mold.
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) | 1979-02-23 | 1979-08-25 | 1980-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-02-23 | 1983-08-25 | 1984-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-02-23 | 1987-08-25 | 1988-02-24 | $7700.00 | Window Closed / Lapsed |