Patent US3825641A successfully refreshed from Google Patents.
US3825641A
Expired / Lapsed
US
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Method of forming multiple passageway plastic conduit
Assignee: Individual
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Filing: 1972-07-20
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Granted: 1974-07-23
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Expires: 1992-07-20
Abstract
Abstract Method for forming conduit having a plurality of longitudinally extending passageways disposed adjacent each other within an exterior wall, the passageways having at least a portion of their interior walls in common with adjacent passageways. The conduit is continuously extruded and sized in a vacuum chamber. Cooling stinger means extending from the die and used to support the conduit until cooled to a non-pliable state. Cooling fluid may be applied interiorly along the passageways so as to effect vertically decreasing pressures within the passageways for further supporting the interior walls thereabout.
Inventors
- 👤 L Barnett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:22
CPC Classifications
B; B29; B29C; B29C53/00; B29C53/02; B29C53/08; B29C53/083; B29C48/00; B29C48/03; B29C48/09; B29C48/11; B29C48/12; B29C48/25; B29C48/88; B29C48/911; B29C48/9115; B29C48/919; B29C48/90; B29C48/905; B29L; B29L2023/00; B29L2023/22; B29L2024/00; B29L2024/006; B29L2031/00; B29L2031/60; B29L2031/601; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24149
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-07-22 | 1978-01-21 | 1978-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-22 | 1982-01-21 | 1982-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-22 | 1986-01-21 | 1986-07-23 | $7700.00 | Window Closed / Lapsed |