US2540932A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making oval diaphragms
Assignee: Individual
•
Filing: 1948-07-10
•
Granted: 1951-02-06
•
Expires: 1968-07-10
Abstract
No abstract record available.
Inventors
- 👤 John T Clark
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:16
CPC Classifications
B; B29; B29D; B29D99/00; B29D99/005; A; A61; A61F; A61F6/00; A61F6/06; A61F6/08; B29L; B29L2031/00; B29L2031/755; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49609
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
58 words
THE METHOD OF PRODUCING A GENERALLY ELLIPTICAL SPRING STRUCTURE AND DIAPHRAGM WHICH COMPRISES THE FOLLOWING STEPS: FORMING A PAIR OF PARTIALLY ELLIPTICAL SPRINGS, FORMING A COIL SPRING, POSITIONING SAID SPRINGS WITHIN SAID COIL SPRING,, AND SECURING THE ENDS OF SAID COIL SPRING TOGETHER TO FORM AN ENDLESS COIL SPRING, SAID PARTIALLY ELLIPTICAL SPRINGS BEING BIASED TO ASSUME AN
Claim 2
Independent Claim
58 words
THE METHOD OF PRODUCING A GENERALLY ELLIPTICAL SPRING STRUCTURE AND DIAPHRAGM WHICH COMPRISES THE FOLLOWING STEPS: FORMING A PAIR OF PARTIALLY ELLIPTICAL SPRINGS, FORMING A COIL SPRING, POSITIONING SAID SPRINGS WITHIN SAID COIL SPRING,, AND SECURING THE ENDS OF SAID COIL SPRING TOGETHER TO FORM AN ENDLESS COIL SPRING, SAID PARTIALLY ELLIPTICAL SPRINGS BEING BIASED TO ASSUME AN
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) | 1954-02-05 | 1954-08-07 | 1955-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-02-05 | 1958-08-07 | 1959-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-02-05 | 1962-08-07 | 1963-02-06 | $7700.00 | Window Closed / Lapsed |