Patent US3729097A successfully refreshed from Google Patents.
US3729097A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filtration of molten metal
Assignee: Alcan Research and Development Ltd
•
Filing: 1971-03-29
•
Granted: 1973-04-24
•
Expires: 1991-03-29
Abstract
Abstract In the production of light metal castings by manual methods molten metal is drawn in a ladle from a pool of metal within a filter floating freely in a body of molten metal in a holding furnace. The filter comprises a body made of a material which is not attacked by the molten metal and is provided with one or more apertures at or near the bottom end, these apertures being covered with filter material so that solid inclusions are removed from molten metal entering the filter body.
Inventors
- 👤 D Collins
- 👤 B Gillett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 19:53
CPC Classifications
C; C22; C22B; C22B9/00; C22B9/02; C22B9/023; B; B01; B01D; B01D29/00; B01D29/01; B22; B22D; B22D39/00; B22D39/02; B22D39/026; B22D43/00; B22D43/001; B22D43/004; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
21 words
A method according to claim 1 in which molten aluminum is filtered by means of a filter member formed of graphite.
Claim 2
Dependent Claim
51 words
A method according to claim 2 in which the pool of molten metal is formed in essentially cylindrical shape by containment in said side wall of essentially cylindrical form, said molten metal being filtered by rising through glass cloth constituting said filter medium closing said bottom end of the filter member.
Claim 3
Dependent Claim
32 words
A method according to claim 3 which includes stabilizing the floating of said member by providing outward support in the molten metal, around the mouth of the member, with a peripheral flange.
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) | 1976-04-23 | 1976-10-23 | 1977-04-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-23 | 1980-10-23 | 1981-04-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-23 | 1984-10-23 | 1985-04-24 | $7700.00 | Window Closed / Lapsed |