Patent US2668131A successfully refreshed from Google Patents.
US2668131A
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Method of making piston rings
Assignee: Muskegon Piston Ring Co
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Filing: 1952-03-08
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Granted: 1954-02-02
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Expires: 1972-03-08
Abstract
No abstract record available.
Inventors
- 👤 Douglas W Hamm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:05
CPC Classifications
F; F16; F16J; F16J9/00; F16J9/12; F16J9/20; F16J9/206; F16J9/203; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49229; Y10T29/49274; Y10T29/49284; Y10T29/49789; Y10T29/4979; Y10T29/49794; Y10T428/00; Y10T428/12; Y10T428/12188; Y10T428/12229; Y10T428/12264; Y10T428/12354; Y10T428/12361
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
96 words
THE METHOD OF MAKING A CIRCUMFERENTIALLY COMPRESSIBLE PISTON RING CONSISTING IN, PROVIDING A CIRCULAR RING MEMBER OF THIN STEEL MATERIAL OF CHANNEL CROSS SECTION, HAVING UPPER AND LOWER SPACED PARALLEL CONTINUOUS HORIZONTAL FLANGES AND A VERTICAL CONNECTING WEB, SAID WEB HAVING A SUCCESSIVE SERIES OF CLOSELY SPACED GENERALLY VERTICAL SLOTS, WITH GENERALLY VERTICAL WEB PORTIONS BETWEEN SAID SLOTS, HEAT TREATING AND HARDENING SAID MEMBER TO A BRITTLE, EASILY FRACTURED CONDITION, FRACTURING EACH FLANGE FROM ITS FREE EDGE TO THE ADJACENT ENDS OF ALTERNATE SLOTS, AND THEREAFTER AGAIN HEAT TREATING THE RING MEMBER TO REDUCE HARDNESS THEREOF.
Claim 2
Independent Claim
96 words
THE METHOD OF MAKING A CIRCUMFERENTIALLY COMPRESSIBLE PISTON RING CONSISTING IN, PROVIDING A CIRCULAR RING MEMBER OF THIN STEEL MATERIAL OF CHANNEL CROSS SECTION, HAVING UPPER AND LOWER SPACED PARALLEL CONTINUOUS HORIZONTAL FLANGES AND A VERTICAL CONNECTING WEB, SAID WEB HAVING A SUCCESSIVE SERIES OF CLOSELY SPACED GENERALLY VERTICAL SLOTS, WITH GENERALLY VERTICAL WEB PORTIONS BETWEEN SAID SLOTS, HEAT TREATING AND HARDENING SAID MEMBER TO A BRITTLE, EASILY FRACTURED CONDITION, FRACTURING EACH FLANGE FROM ITS FREE EDGE TO THE ADJACENT ENDS OF ALTERNATE SLOTS, AND THEREAFTER AGAIN HEAT TREATING THE RING MEMBER TO REDUCE HARDNESS THEREOF.
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) | 1957-02-01 | 1957-08-03 | 1958-02-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-02-01 | 1961-08-03 | 1962-02-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-02-01 | 1965-08-03 | 1966-02-02 | $7700.00 | Window Closed / Lapsed |