US3394877A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rotary piston engine
Assignee: SACHWENRING AUTOMOBILWERKE ZWI
•
Filing: 1966-12-15
•
Granted: 1968-07-30
•
Expires: 1986-12-15
Abstract
No abstract record available.
Inventors
- 👤 Hantzsche Helmut
- 👤 Uhlig Hellmut
- 👤 Muller Walter
- 👤 Lang Werner
- 👤 Bruckner Karl Heinz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 07:35
CPC Classifications
F; F02; F02B; F02B53/00; F02B2053/005; F02B2730/00; F02B2730/01; F02B2730/018; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12; Y10; Y10S; Y10S417/00; Y10S417/01
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
156 words
IN A ROTARY PISTON ENGINE, AN OUTER HOUSING HAVING AN INNER SURFACE AND A ROTARY PISTON SITUATED IN SAID OUTER HOUSING AND CARRYING SEALING ELEMENTS WHICH SLIDABLY ENGAGE SAID INNER SURFACE OF SAID OUTER HOUSING, SAID HOUSING HAVING IN THE REGION OF ITS INNER SURFACE AN INNER LAYER, WHICH IS SLIDABLY ENGAGED BY SAID SEALING ELEMENTS, AN INTERMEDIATE LAYER JOINED TO SAID INNER LAYER, AND A WALL STRUCTURE JOINED TO SAID INTERMEDIATE LAYER, SAID INTERMEDIATE LAYER BEING SITUATED BETWEEN SAID WALL STRUCTURE AND INNER LAYER AND BEING MADE OF GAS-CARBURIZED TUNGSTEN CARBIDE HAVING A GRANULAR SIZE WHICH IS SMALLER THAN 40 UM., HAVING A CARBON CONTENT OF 2-2.7%, AND SAID INNER LAYER BEING TUNGSTEN CABIDE HAVING A COBALT ADDITIVE CONTENT OF 10-20% AND MADE UP OF GRAINS 60% OF WHICH HAVE A MICROHARDNESS OF APPROXIMATELY 640-783 TONS/SQ. IN. WITH A FRACTION OF HARDER LAYER MATERIAL, OF 1,423 TONS/SQ. IN. AND MORE. CONSTITUTING A MAXIMUM OF 4%.
Claim 2
Dependent Claim
156 words
IN A ROTARY PISTON ENGINE, AN OUTER HOUSING HAVING AN INNER SURFACE AND A ROTARY PISTON SITUATED IN SAID OUTER HOUSING AND CARRYING SEALING ELEMENTS WHICH SLIDABLY ENGAGE SAID INNER SURFACE OF SAID OUTER HOUSING, SAID HOUSING HAVING IN THE REGION OF ITS INNER SURFACE AN INNER LAYER, WHICH IS SLIDABLY ENGAGED BY SAID SEALING ELEMENTS, AN INTERMEDIATE LAYER JOINED TO SAID INNER LAYER, AND A WALL STRUCTURE JOINED TO SAID INTERMEDIATE LAYER, SAID INTERMEDIATE LAYER BEING SITUATED BETWEEN SAID WALL STRUCTURE AND INNER LAYER AND BEING MADE OF GAS-CARBURIZED TUNGSTEN CARBIDE HAVING A GRANULAR SIZE WHICH IS SMALLER THAN 40 UM., HAVING A CARBON CONTENT OF 2-2.7%, AND SAID INNER LAYER BEING TUNGSTEN CABIDE HAVING A COBALT ADDITIVE CONTENT OF 10-20% AND MADE UP OF GRAINS 60% OF WHICH HAVE A MICROHARDNESS OF APPROXIMATELY 640-783 TONS/SQ. IN. WITH A FRACTION OF HARDER LAYER MATERIAL, OF 1,423 TONS/SQ. IN. AND MORE. CONSTITUTING A MAXIMUM OF 4%.
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) | 1971-07-30 | 1972-01-29 | 1972-07-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-07-30 | 1976-01-29 | 1976-07-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-07-30 | 1980-01-29 | 1980-07-30 | $7700.00 | Window Closed / Lapsed |