Patent US4140728A successfully refreshed from Google Patents.
Patent US3797986A successfully refreshed from Google Patents.
US3797986A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for hot pressing of ceramic materials
Assignee: Rio Tinto Switzerland AG
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Filing: 1972-10-04
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Granted: 1974-03-19
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Expires: 1992-10-04
Abstract
Abstract A device for hot pressing of ceramic materials in powder form or fine granular form, comprising a mold defining a longitudinal cavity and built up of graphite plates arranged in succession along its length each plate lying perpendicular to the wall of the mold cavity, at least one layer between each plate and the next, these layers being resistant to high temperature, electrically ensulating, and ceasing at some distance from the wall of the mold cavity, and electrically conducting carbon material filling the slots thus resulting in the wall of the mold cavity.
Inventors
- 👤 H Onder
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 15:01
CPC Classifications
B; B30; B30B; B30B11/00; B30B11/007; B28; B28B; B28B3/00; B28B3/02; B28B3/025; B28B3/08; B28B3/086; B28B7/00; B28B7/34; B30B15/00; B30B15/02; B30B15/34
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
117 words
A device for hot pressing of ceramic materials in powder form or fine granular form, comprising a mold defining a longitudinal cavity and built up of graphite plates arranged in succession along its length, each plate lying perpendicular to the wall of said mold cavity, at least one relatively thin layer between each plate and the next, said layers being resistant to high temperature, electrically insulating, and ceasing at a distance from the wall of said mold cavity, and electrically conducting carbon material filling the slots thus resulting in the wall of said mold cavity, means for electrically heating said mold, and opposed press members adapted to enter said longitudinal cavity for hot pressing ceramic materials therein.
Claim 2
Independent Claim
117 words
A device for hot pressing of ceramic materials in powder form or fine granular form, comprising a mold defining a longitudinal cavity and built up of graphite plates arranged in succession along its length, each plate lying perpendicular to the wall of said mold cavity, at least one relatively thin layer between each plate and the next, said layers being resistant to high temperature, electrically insulating, and ceasing at a distance from the wall of said mold cavity, and electrically conducting carbon material filling the slots thus resulting in the wall of said mold cavity, means for electrically heating said mold, and opposed press members adapted to enter said longitudinal cavity for hot pressing ceramic materials therein.
Claim 3
Dependent Claim
32 words
A device according to claim 1, the electrically insulating layers ceasing at a distance not less than 1 mm and not greater than 5 mm from the wall of the mold cavity.
Claim 4
Dependent Claim
42 words
A device according to claim 1, in which the mold is divided into longitudinal segments, and surrounding these longitudinal segments there is a frame which is able to withstand the forces which emanate from the mold cavity during use of said device.
Claim 5
Dependent Claim
109 words
A device according to claim 1, in which the mold cavity has a polyhedral cross section and in which device the mold is divided into longitudinal segments having sliding surfaces which are parallel to the corresponding surfaces of said cavity and perpendicular to the axis of said mold, said segments being so movable along said sliding surfaces that the said mold cavity maintains its cross sectional shape both on pulling apart and also pushing together said longitudinal segments and in which mold, surrounding the said longitudinal segments, there is a frame which is able to withstand the forces which emanate from said mold cavity during use of the device.
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) | 1977-03-18 | 1977-09-17 | 1978-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-18 | 1981-09-17 | 1982-03-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-18 | 1985-09-17 | 1986-03-19 | $7700.00 | Window Closed / Lapsed |