Patent US3307543A successfully refreshed from Google Patents.
US3307543A
Expired / Lapsed
US
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Cover for a respirator filter holder
Assignee: Welsh Manufacturing Co
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Filing: 1964-10-26
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Granted: 1967-03-07
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Expires: 1984-10-26
Abstract
No abstract record available.
Inventors
- 👤 Silverman Leslie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 12:58
CPC Classifications
A; A62; A62B; A62B18/00; A62B18/02; A62B18/025; Y; Y10; Y10S; Y10S128/00; Y10S128/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
77 words
IN A RESPIRATOR, A FILTER HOLDER COMPRISING A BODY, A FILTER WITHIN THE BODY, A WALL ATTACHED TO THE BODY, SAID WALL BEING PROVIDED WITH A PLURALITY OF LOUVERS RADIATING FROM A COMMON CENTER AND ARRANGED IN AN ECHELON RELATION CIRCULARLY ABOUT SAID CENTER AND A CIRCULAR RIB INTERMEDIATE THE ENDS OF SAID LOUVERS CARRIED BY SAID WALL AND OF A DIMENSION EXTENDING BEYOND THE INNER EDGES OF THE LOUVERS AND SPACING THE FILTER FROM SAID WALL.
Claim 2
Dependent Claim
77 words
IN A RESPIRATOR, A FILTER HOLDER COMPRISING A BODY, A FILTER WITHIN THE BODY, A WALL ATTACHED TO THE BODY, SAID WALL BEING PROVIDED WITH A PLURALITY OF LOUVERS RADIATING FROM A COMMON CENTER AND ARRANGED IN AN ECHELON RELATION CIRCULARLY ABOUT SAID CENTER AND A CIRCULAR RIB INTERMEDIATE THE ENDS OF SAID LOUVERS CARRIED BY SAID WALL AND OF A DIMENSION EXTENDING BEYOND THE INNER EDGES OF THE LOUVERS AND SPACING THE FILTER FROM SAID WALL.
References Cited (Backward Citations)
AU565527A
Cited
US3029812A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-03-06 | 1970-09-05 | 1971-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-03-06 | 1974-09-05 | 1975-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-03-06 | 1978-09-05 | 1979-03-07 | $7700.00 | Window Closed / Lapsed |