Patent US3874784A successfully refreshed from Google Patents.
US3874784A
Expired / Lapsed
US
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Signal reflector with convex reflectors secured to a transparent sphere
Assignee: 3M Co
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Filing: 1973-06-15
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Granted: 1975-04-01
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Expires: 1993-06-15
Abstract
Abstract The disclosure describes a method for producing aggregates designed for the manufacture of catoptrically behaving composite reflecting systems and each having a transparent sphere provided with a transparent layer thereabout and a plurality of convex reflective surfaces closedly formed into said transparent layer. The method comprises forming said transparent layer with a composition such to provide a non-sticky and non-permanently bead receptive layer, impinging beads on said layer until closedly spaced concavities are formed in said layer, applying metered amounts of fluidized transparent material in said concavities for making shallower cavities in same locations, and providing a reflective surface on said shallower cavities. The thus formed aggregates are also described.
Inventors
- 👤 Ludwig Eigenmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:15
CPC Classifications
B; B29; B29D; B29D11/00; B29D11/00605; B29D11/00615; B44; B44F; B44F1/00; B44F1/02; B44F1/04; E; E01; E01F; E01F9/00; E01F9/50; E01F9/506; E01F9/524; G; G02; G02B; G02B5/00; G02B5/12; G02B5/126; G02B5/128
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
71 words
As a new article of manufacture, an improved catoptrically behaving retro-reflecting system, which includes a main transparent sphere designed to have an uncoated spherical portion positioned for light impingement, a transparent coating, and closely spaced shallow spherical recesses in said coating, the radii of curvature of said recesses being greater than half of the inter-axial interval between said recesses, and reflective means on the outer surface of said shallow spherical recesses.
Claim 2
Dependent Claim
71 words
As a new article of manufacture, an improved catoptrically behaving retro-reflecting system, which includes a main transparent sphere designed to have an uncoated spherical portion positioned for light impingement, a transparent coating, and closely spaced shallow spherical recesses in said coating, the radii of curvature of said recesses being greater than half of the inter-axial interval between said recesses, and reflective means on the outer surface of said shallow spherical recesses.
Claim 3
Dependent Claim
146 words
An improved reflecting system, particularly a catoptrically-behaving retroreflective system or the like, comprising a plurality of light-conductive spherical bodies, each having at least two outer surface portions, one of which is to be positioned to receive impinging light from an external light source; a light-conductive coating having at least two constituent parts, a first constituent part being deposited uniformly about both of said outer surface portions and being formed with part-spherical indentations, and a second constituent part partly filling only those of said indentations which are located on said other surface portion of the respective spherical bodies; and reflective means coating said second constituent part and being reflective inwardly of the respective spherical body so as to reflect light which impinges through said one outer surface portion, and direct it back through said one outer surface portion in a direction substantially towards said external light source.
Claim 4
Dependent Claim
146 words
An improved reflecting system, particularly a catoptrically-behaving retroreflective system or the like, comprising a plurality of light-conductive spherical bodies, each having at least two outer surface portions, one of which is to be positioned to receive impinging light from an external light source; a light-conductive coating having at least two constituent parts, a first constituent part being deposited uniformly about both of said outer surface portions and being formed with part-spherical indentations, and a second constituent part partly filling only those of said indentations which are located on said other surface portion of the respective spherical bodies; and reflective means coating said second constituent part and being reflective inwardly of the respective spherical body so as to reflect light which impinges through said one outer surface portion, and direct it back through said one outer surface portion in a direction substantially towards said external light source.
Claim 5
Dependent Claim
63 words
A reflecting system as defined in claim 2, wherein said first constituent part of said light-conductive mixture is flowable and non-adhesive at a first lower temperature and settable at a second higher temperature; and wherein said first constituent part is capable of being impinged on its outer surface area and of retaining the shape of a heated impinging article after impingement has occurred.
Claim 6
Dependent Claim
60 words
A reflecting system as defined in claim 3, wherein said second constituent of said light-conductive mixture is flowable at a first lower temperature and settable at a second higher temperature; and wherein said second constituent part forms said indentations of large radii of curvature by partially filling said indentations with said second constituent and allowing said second constituent to set.
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) | 1978-03-31 | 1978-09-30 | 1979-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-31 | 1982-09-30 | 1983-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-31 | 1986-09-30 | 1987-04-01 | $7700.00 | Window Closed / Lapsed |