Patent US3138391A successfully refreshed from Google Patents.
US3138391A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Piston ring assembly
Assignee: Perfect Circle Corp
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Filing: 1962-01-29
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Granted: 1964-06-23
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Expires: 1982-01-29
Abstract
No abstract record available.
Inventors
- 👤 William H Charlesworth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:22
CPC Classifications
F; F16; F16J; F16J9/00; F16J9/06; F16J9/064; F16J9/066
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
82 words
A SPACER-EXPANDER FOR A PISTON RING ASSEMBLY INCLUDING A PAIR OF RAILS, COMPRISING A PAIR OF AXIALLY SPACED CIRCUMFERENTIALLY EXPANSIBLE SPRING STRUCTURES, AXIALLY EXTENDING STRUTS CONNECTING SAID SPRING STRUCTURES AT THEIR OUTER EDGES, SAID SPRING STRUCTURES HAVING INNER PORTIONS BENT AXIALLY TOWARD EACH OTHER AND FORMING A BOX-LIKE STRUCTURE WITH SAID STRUTS, SAID SPRING STRUCTURES INCLUDING RAIL SUPPORTING PORTIONS CONNECTED BY SPRING ELEMENTS, AND THE INNER PORTIONS OF SAID SPRING ELEMENTS BEING BENT AXIALLY TOWARD EACH OTHER TO FORM SAID BOX-LIKE STRUCTURE.
Claim 2
Dependent Claim
82 words
A SPACER-EXPANDER FOR A PISTON RING ASSEMBLY INCLUDING A PAIR OF RAILS, COMPRISING A PAIR OF AXIALLY SPACED CIRCUMFERENTIALLY EXPANSIBLE SPRING STRUCTURES, AXIALLY EXTENDING STRUTS CONNECTING SAID SPRING STRUCTURES AT THEIR OUTER EDGES, SAID SPRING STRUCTURES HAVING INNER PORTIONS BENT AXIALLY TOWARD EACH OTHER AND FORMING A BOX-LIKE STRUCTURE WITH SAID STRUTS, SAID SPRING STRUCTURES INCLUDING RAIL SUPPORTING PORTIONS CONNECTED BY SPRING ELEMENTS, AND THE INNER PORTIONS OF SAID SPRING ELEMENTS BEING BENT AXIALLY TOWARD EACH OTHER TO FORM SAID BOX-LIKE STRUCTURE.
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) | 1967-06-23 | 1967-12-23 | 1968-06-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-06-23 | 1971-12-23 | 1972-06-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-06-23 | 1975-12-23 | 1976-06-23 | $7700.00 | Window Closed / Lapsed |