Patent US3672798A successfully refreshed from Google Patents.
US3672798A
Expired / Lapsed
US
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Radial sealing bar for pistons of rotary piston internal combustion engines
Assignee: Daimler Benz AG
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Filing: 1970-03-06
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Granted: 1972-06-27
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Expires: 1990-03-06
Abstract
Abstract A RADIAL SEALING BAR OF COMPOSITE CONSTRUCTION FOR PISTONS OF ROTARY PISTON INTERNAL COMBUSTION ENGINES, ESPECIALLY OF TROCHOIDAL CONSTRUCTION IN WHICH THE RADIAL SEALING BAR CONSISTS OF AT LEAST THREE THIN LAYERS WHICH EXTENT IN THE LONGITUDINAL DIRECTION; AT LEAST THE LAYER WHICH FORMS A PART OF THE BAR CREST IS MADE FROM A MATERIAL HAVING A HIGH HARDNESS, SUCH AS A CERAMIC MATERIAL, QUARTZ, A HARD METAL OR ALLOY AND OTHER SINTERED MATERIALS.
Inventors
- 👤 Hans O Scherenberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:57
CPC Classifications
F; F01; F01C; F01C19/00; F01C19/005; F01C19/10; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49229; Y10T29/49249
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) | 1975-06-27 | 1975-12-27 | 1976-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-27 | 1979-12-27 | 1980-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-27 | 1983-12-27 | 1984-06-27 | $7700.00 | Window Closed / Lapsed |