Patent US4722101A successfully refreshed from Google Patents.
US4722101A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical system for protective headgear
Assignee: Individual
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Filing: 1986-08-20
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Granted: 1988-02-02
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Expires: 2006-08-20
Abstract
Abstract A helmet includes an optical system presenting a rearward view to the wearer as an image below the wearer's horizontal line of sight and including a plurality of optical components arranged such that the image is viewed through a viewing component positioned adjacent to the wearer's forward line of sight and below the horizontal line of sight. The remaining components are positioned such that the optical path from the rearward view to the viewing component is routed around one side of the helmet. The optical system is housed in a "knock-off" unit and is sealed to prevent condensation. The helmet may be used by motorcyclists or security guards and provides a compact arrangement having a wide field of view.
Inventors
- 👤 David H. Blower
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:20
CPC Classifications
A; A42; A42B; A42B3/00; A42B3/04; A42B3/0406; A42B3/042; A42B3/0426
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
98 words
A protective helmet comprising an optical system for presenting a rearward view to the wearer, said optical system comprising a plurality of optical components including a viewing component through which the image is viewed and which is positioned adjacent to the wearer's forward line of sight and below the horizontal line of sight, and remaining components of said optical system positioned such that the optical path from the rearward view to the viewing component is routed around one side of the helmet so as to present the view as an image below the wearer's horizontal line of sight.
Claim 2
Dependent Claim
98 words
A protective helmet comprising an optical system for presenting a rearward view to the wearer, said optical system comprising a plurality of optical components including a viewing component through which the image is viewed and which is positioned adjacent to the wearer's forward line of sight and below the horizontal line of sight, and remaining components of said optical system positioned such that the optical path from the rearward view to the viewing component is routed around one side of the helmet so as to present the view as an image below the wearer's horizontal line of sight.
Claim 3
Dependent Claim
48 words
A helmet as claimed in claim 1 wherein the viewing component is arranged to be viewed at more than 15 degrees below the horizontal line of sight of the wearer and with a lateral angle of deflection from the forward line of sight of less than 50 degrees.
Claim 4
Dependent Claim
54 words
A helmet as claimed in claim 2 wherein at least one of the optical components is selected to be a non-planar mirror or lens and the optical system has an overall angular magnification of less than unity so as to present a rearward view of greater field than that available using corresponding planar components.
Claim 5
Dependent Claim
39 words
A helmet as claimed in claim 3 wherein the viewing component is a concave viewing mirror and the optical path from the rearward view to the viewing mirror is routed via a convex mirror and a concave mirror respectively.
Claim 6
Dependent Claim
39 words
A helmet as claimed in claim 3 wherein the viewing component is a plane viewing mirror and the optical path from the rearward view to the viewing mirror is routed via a convex mirror and a concave mirror respectively.
Claim 7
Dependent Claim
36 words
A helmet as claimed in claim 1 which further comprises a unit in which the optical system is housed, which unit has a "knock off" facility whereby the unit is detachable from the helmet when knocked.
Claim 8
Dependent Claim
29 words
A helmet as claimed in claim 6 wherein the optical system is made suitable for the eye positions of different users by adjustment to the lining of the helmet.
Claim 9
Dependent Claim
29 words
A helmet as claimed in claim 7 wherein the optical system is sealed to prevent condensation with provision of an expansion facility to cope with changes of gas pressure.
Claim 10
Dependent Claim
26 words
A helmet as claimed in claim 8 wherein a viewing window is inclined towards the wearer by at least 20° above the horizontal line of sight.
Claim 11
Dependent Claim
94 words
An optical system for presenting a rearward view to the wearer of a helmet comprising a plurality of optical components including a viewing component through which the image is viewed and which is positioned adjacent to the wearer's forward line of sight and below the horizontal line of sight, and remaining components of said optical system positioned such that the optical path from the rearward view to the viewing component is routed around one side of the helmet so as to present the view as an image below the wearer's horizontal line of sight.
Claim 12
Dependent Claim
94 words
An optical system for presenting a rearward view to the wearer of a helmet comprising a plurality of optical components including a viewing component through which the image is viewed and which is positioned adjacent to the wearer's forward line of sight and below the horizontal line of sight, and remaining components of said optical system positioned such that the optical path from the rearward view to the viewing component is routed around one side of the helmet so as to present the view as an image below the wearer's horizontal line of sight.
Claim 13
Dependent Claim
98 words
A helmet adapted for the attachment of an optical system for presenting a rearward view to the wearer comprising a plurality of optical components including a viewing component through which the image is viewed and which is positioned adjacent to the wearer's forward line of sight and below the horizontal line of sight, and remaining components of said optical system positioned such that the optical path from the rearward view to the viewing component is routed around one side of the helmet so as to present the view as an image below the wearer's horizontal line of sight.
Claim 14
Dependent Claim
98 words
A helmet adapted for the attachment of an optical system for presenting a rearward view to the wearer comprising a plurality of optical components including a viewing component through which the image is viewed and which is positioned adjacent to the wearer's forward line of sight and below the horizontal line of sight, and remaining components of said optical system positioned such that the optical path from the rearward view to the viewing component is routed around one side of the helmet so as to present the view as an image below the wearer's horizontal line of sight.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-02-01 | 1991-08-03 | 1992-02-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-02-01 | 1995-08-03 | 1996-02-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-02-01 | 1999-08-03 | 2000-02-02 | $7700.00 | Window Closed / Lapsed |