Patent US4175824A successfully refreshed from Google Patents.
US4175824A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Door viewer with barrel flange and mating lens recess
Assignee: Individual
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Filing: 1977-09-13
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Granted: 1979-11-27
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Expires: 1997-09-13
Abstract
Abstract Disclosed are alternative embodiments of a barrel type optical viewer for installation in a door or other type partition where the wide angle lens of the viewer is so connected with the forward barrel flange to avoid obstruction of the periphery of the lens. The lens is either permanently secured to the face of the flange or removably coupled therewith; and the interior bore of the barrel is lined or otherwise provided with opaque material.
Inventors
- 👤 Nicholas G. Daley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:52
CPC Classifications
G; G02; G02B; G02B25/00; G02B25/04; E; E06; E06B; E06B7/00; E06B7/28; E06B7/30
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
140 words
A door viewer, comprising: (a) a generally cylindrical shaped barrel having an interior wall defining an axially extending elongated bore, said barrel terminating at its forward end in a generally circular shaped flange, (b) first lens means retained within the forward end of said bore, and second lens means retained within said bore and axially spaced from said first lens means, (c) said flange having a substantially flat forward surface, and (d) a wide angle viewing lens secured to the flat surface of, and removably coupled with, said flange, said wide angle viewing lens having an outside diameter at least equal to the outside diameter of said flange and further having a centrally disposed recess in the base portion thereof for mateable reception of said flange, the circumferential end portion of said wide angle viewing lens resiliently engaging said flange.
Claim 2
Dependent Claim
140 words
A door viewer, comprising: (a) a generally cylindrical shaped barrel having an interior wall defining an axially extending elongated bore, said barrel terminating at its forward end in a generally circular shaped flange, (b) first lens means retained within the forward end of said bore, and second lens means retained within said bore and axially spaced from said first lens means, (c) said flange having a substantially flat forward surface, and (d) a wide angle viewing lens secured to the flat surface of, and removably coupled with, said flange, said wide angle viewing lens having an outside diameter at least equal to the outside diameter of said flange and further having a centrally disposed recess in the base portion thereof for mateable reception of said flange, the circumferential end portion of said wide angle viewing lens resiliently engaging said flange.
References Cited (Backward Citations)
US2146662A
Cited
US2229594A
Cited
US2538077A
Cited
FR1254122A
Cited
FR1378584A
Cited
FR1378602A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-11-26 | 1983-05-28 | 1983-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-11-26 | 1987-05-28 | 1987-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-11-26 | 1991-05-28 | 1991-11-27 | $7700.00 | Window Closed / Lapsed |