US3679893A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Luminaire reflector comprising elliptical and parabolic segments
Assignee: Sylvan R Schemitz and Associates Inc
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Filing: 1970-09-03
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Granted: 1972-07-25
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Expires: 1990-09-03
Abstract
Abstract Substantially uniform magnitude of illumination on a plane surface is provided by a concave reflector having a parabolic reflecting surface and an elliptical reflecting surface oriented relative to one another to satisfy the following criteria. A. THE FIRST FOCAL POINT OF THE ELLIPTICAL SURFACE IS ON THE AXIS OF THE PARABOLIC SURFACE, B. THE SECOND FOCAL POINT OF THE ELLIPTICAL SURFACE IS NOT WITHIN THE CLOSURE FORMED BY THE INNER SURFACES OF THE REFLECTING SURFACES AND A PLANE ACROSS THE OUTWARDLY EXTENDING EDGES OF THE SURFACES, C. THE AXIS OF THE PARABOLIC SURFACE IS FROM ABOUT 45* TO ABOUT 90* FROM NADIR, AND D. THE MAJOR AXIS OF THE ELLIPTICAL SURFACE IS FROM ABOUT 5* TO ABOUT 45* FROM NADIR. Preferred embodiments include the parabolic surface and elliptical surface separated by one or more general reflecting surfaces, and the same combinations of surfaces with a second parabolic reflecting surface or flat reflecting surface adjacent and below the first parabolic surface and a flat reflecting surface adjacent and outside of the elliptical surface. The additional surfaces provide further improvement in control of the reflections.
Inventors
- 👤 Sylvan R Shemitz
- 👤 Benjamin L Stahlheber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:29
CPC Classifications
F; F21; F21V; F21V7/00; F21V7/04; F21V7/09; F21W; F21W2131/00; F21W2131/10; F21W2131/107; F21Y; F21Y2103/00
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
197 words
In a concave reflector, the combination of: 1. a first reflecting surface parabolic in section, 2. a second reflecting surface elliptical in section, said surfaces being positioned relative to each other such that: a. the first focal point of said elliptical surface is on the axis of said parabolic surface, b. the second focal point of said elliptical surface is not within the closure formed by said reflecting surfaces and a plane across the outwardly extending edges of said surfaces, c. the axis of said parabolic surface is from about 45* to about 90* from nadir, and d. the major axis of said elliptical surface is from about 5* to about 45* from nadir, and 3. means adjacent the outer rim of said first reflecting surface, for reflecting first reflections from said elliptical surface, when substantially all of said first reflections are not reflected into the -10* to +65* zone from nadir, into said zone; whereby, when a light source is placed at said first focal point, light is reflected from said concave reflector in an asymmetric pattern to produce substantially constant magnitude of illumination on a plane and to reduce discomfort glare and disability veiling glare.
Claim 2
Dependent Claim
197 words
In a concave reflector, the combination of: 1. a first reflecting surface parabolic in section, 2. a second reflecting surface elliptical in section, said surfaces being positioned relative to each other such that: a. the first focal point of said elliptical surface is on the axis of said parabolic surface, b. the second focal point of said elliptical surface is not within the closure formed by said reflecting surfaces and a plane across the outwardly extending edges of said surfaces, c. the axis of said parabolic surface is from about 45* to about 90* from nadir, and d. the major axis of said elliptical surface is from about 5* to about 45* from nadir, and 3. means adjacent the outer rim of said first reflecting surface, for reflecting first reflections from said elliptical surface, when substantially all of said first reflections are not reflected into the -10* to +65* zone from nadir, into said zone; whereby, when a light source is placed at said first focal point, light is reflected from said concave reflector in an asymmetric pattern to produce substantially constant magnitude of illumination on a plane and to reduce discomfort glare and disability veiling glare.
Claim 3
Dependent Claim
99 words
a second reflecting surface elliptical in section, said surfaces being positioned relative to each other such that: a. the first focal point of said elliptical surface is on the axis of said parabolic surface, b. the second focal point of said elliptical surface is not within the closure formed by said reflecting surfaces and a plane across the outwardly extending edges of said surfaces, c. the axis of said parabolic surface is from about 45* to about 90* from nadir, and d. the major axis of said elliptical surface is from about 5* to about 45* from nadir, and
Claim 4
Dependent Claim
99 words
a second reflecting surface elliptical in section, said surfaces being positioned relative to each other such that: a. the first focal point of said elliptical surface is on the axis of said parabolic surface, b. the second focal point of said elliptical surface is not within the closure formed by said reflecting surfaces and a plane across the outwardly extending edges of said surfaces, c. the axis of said parabolic surface is from about 45* to about 90* from nadir, and d. the major axis of said elliptical surface is from about 5* to about 45* from nadir, and
Claim 5
Dependent Claim
29 words
A concave reflector as in claim 1 wherein reflecting means (3) is a parabolic surface the axis of which passes through the second focal point of said elliptical surface.
Claim 6
Dependent Claim
38 words
A concave reflector as in claim 2 including at least one flat reflecting surface adjacent the outer rim of said reflecting means (3), so disposed as to reflect into the zone encompassed by -10* to +65* from nadir.
Claim 7
Dependent Claim
81 words
means adjacent the outer rim of said first reflecting surface, for reflecting first reflections from said elliptical surface, when substantially all of said first reflections are not reflected into the -10* to +65* zone from nadir, into said zone; whereby, when a light source is placed at said first focal point, light is reflected from said concave reflector in an asymmetric pattern to produce substantially constant magnitude of illumination on a plane and to reduce discomfort glare and disability veiling glare.
Claim 8
Dependent Claim
81 words
means adjacent the outer rim of said first reflecting surface, for reflecting first reflections from said elliptical surface, when substantially all of said first reflections are not reflected into the -10* to +65* zone from nadir, into said zone; whereby, when a light source is placed at said first focal point, light is reflected from said concave reflector in an asymmetric pattern to produce substantially constant magnitude of illumination on a plane and to reduce discomfort glare and disability veiling glare.
Claim 9
Dependent Claim
63 words
A concave reflector as in claim 2 wherein, on a compass having as its origin the first focal point of said second reflecting surface, said first reflecting surface in section extends from 212* to about 288*, said second reflecting surface in section extends from about 44* to about 110*, and said reflecting means (3) in section extends from about 192* to about 212*.
Claim 10
Dependent Claim
80 words
A concave reflector as in claim 4 including three general reflecting surfaces disposed between said first and second reflecting surfaces, one of said general reflecting surfaces in section extending from about 287* to about 308*, the second of said general reflecTing surfaces in section extending from about 308* to about 338*, and the third general reflecting surface in section extending from about 2* to about 44*, the space between the second and third general reflecting surfaces being a ventilation slot.
Claim 11
Dependent Claim
23 words
A concave reflector as in claim 5 including at least one flat reflecting surface in section extending from about 187* to about 192*.
Claim 12
Dependent Claim
34 words
A concave reflector as in claim 1 including a general reflecting surface disposed between said first and second reflecting surfaces so as to reflect into the zone encompassed by -10* to +65* from nadir.
Claim 13
Dependent Claim
64 words
A concave reflector as in claim 7 wherein, on a compass having as its origin the first focal point of said second reflecting surface, said first reflecting surface in section extends from about 197* to about 238*, said second reflecting surface in section extends from about 0* to about 84*, and said general reflecting surface in section extends from about 242* to about 343*.
Claim 14
Dependent Claim
17 words
A concave reflector as in claim 1 wherein reflecting means (3) is a first flat reflecting surface.
Claim 15
Dependent Claim
36 words
A concave reflector as in claim 1 including a flat reflecting surface adjacent the outer rim of said second reflecting surface, so disposed as to reflect into the zone encompassed by -10* to +65* from nadir.
Claim 16
Dependent Claim
62 words
A concave reflector as in claim 1 wherein reflecting means (3) is a parabolic surface, the axis of which passes through the second focal point of said elliptical surface, said concave reflector further including at least one general reflecting surface disposed between said first and second reflecting surfaces so as to reflect into the zone encompassed by -10* to +65* from nadir.
Claim 17
Dependent Claim
25 words
The concave reflector of claim 11 wherein the general reflecting surface is in three portions separated by a ventilation slot between two of said portions.
Claim 18
Dependent Claim
64 words
A concave reflector as in claim 1 wherein reflecting means (3) is a first flat reflecting surface, said first flat reflecting surface in section extending from about 180* to about 198*, said concave reflector further including a second flat reflecting surface adjacent the outer rim of said second reflecting surface, said second flat reflecting surface in section extending from about 88* to about 101*.
Claim 19
Dependent Claim
40 words
In a luminaire, the combination of: a concave reflector as in claim 1, a housing for said reflector, means for supporting said reflector in said housing, and a light source placed at said first focal point of said elliptical surface.
Claim 20
Dependent Claim
76 words
A concave reflector as in claim 1 wherein said reflecting means (3) is a first flat reflecting surface; said concave reflector further including a general reflecting surface between said first and second reflecting surfaces, and a second flat reflecting surface adjacent the outer rim of said second reflecting surface, said general reflecting surface and said second flat reflecting surface each being positioned so as to reflect into the zone encompassed by -10* to +65* from nadir.
Claim 21
Dependent Claim
92 words
A concave reflector as in claim 15 wherein, on a compass having as its origin the first focal point of said second reflecting surface: said first reflecting surface in section extends from about 197* to about 238*; said second reflecting surface in section extends from about 0* to about 84*; said first flat reflecting surface in section extends from about 180* to about 198*; said second flat reflecting surface in section extends from about 88* to about 101*; and said general reflecting surface in section extends from about 242* to about 343*.
Claim 22
Dependent Claim
91 words
A concave reflector as in claim 1 wherein said reflecting means (3) is a parabolic surface the axis of which passes through the second focal point of said second reflecting surface; said concave reflector further including at least one general reflecting surface between said first and second reflecting surfaces, and at least one flat reflecting surface adjacent the outer rim of said reflecting means (3), said general reflecting surface and said flat reflecting surface each being positioned so as to reflect into the zone encompassed by -10* to +65* from nadir.
Claim 23
Dependent Claim
26 words
A concave reflector as in claim 17 wherein the general reflecting surface is in three portions separated by a ventilation slot between two of said portions.
Claim 24
Dependent Claim
142 words
A concave reflector as in claim 17 wherein, on a compass having as its origin the first focal point of said second reflecting surface: said first reflecting surface in section extends from about 212* to about 288* ; said second reflecting surface in section extends from about 44* to about 110* ; said reflecting means (3) in section extends from about 192* to about 212* ; said general reflecting surface is in three portions, one of said portions in section extending from about 287* to about 308*, the second in section extending from about 308* to about 338* and the third in section extending from about 2* to about 44*, the space between the second and third portions being a ventilation slot; and said flat reflecting surface is in two portions, together in section extending from about 185* to about 192* .
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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) | 1975-07-25 | 1976-01-24 | 1976-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-25 | 1980-01-24 | 1980-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-25 | 1984-01-24 | 1984-07-25 | $7700.00 | Window Closed / Lapsed |