Daylight collection systems and methods

• US 8,837,048 B2
• Filed: 11/28/2012
• Issued: 09/16/2014
• Est. Priority Date: 11/30/2011
• Status: Active Grant

• Current Assignee: Solatube International, Inc. (Kingspan Group PLC)
• Original Assignee: Solatube International, Inc. (Kingspan Group PLC)
• Inventors: Jaster, Paul August
• Primary Examiner(s): MAHONEY, CHRISTOPHER E
• Application Number:
  US13/687,803
• Publication Number:
  US 20130135744A1
• Time in Patent Office: 657 Days
• Field of Search: 359/591, 359/597, 359/592
• US Class Current: 359/592
• CPC Class Codes: E04D 13/0305 Supports or connecting means for sky-lights of flat or domed shape
• CPC Class Codes: E04D 13/033 provided with means for controlling the light-transmission or the heat-reflection, (e.g. shields, reflectors, cleaning devices)
• CPC Class Codes: E04D 2013/0345 with skylight shafts extending from roof to ceiling
• CPC Class Codes: F21S 11/002 characterised by the means for collecting or concentrating the sunlight, e.g. parabolic reflectors or Fresnel lenses
• CPC Class Codes: F21S 11/007 characterised by the means for transmitting light into the interior of a building
• CPC Class Codes: G02B 17/00 Systems with reflecting surfaces, with or without refracting elements
• CPC Class Codes: G02B 19/0028 refractive and reflective surfaces, e.g. non-imaging catadioptric systems
• CPC Class Codes: G02B 19/0038 for use with ambient light G02B19/009, G02B19/0095 take precedence
• CPC Class Codes: G02B 19/0042 for use with direct solar radiation

Abstract

Lighting devices and methods for illuminating the interior of a building with natural daylight are disclosed. In some embodiments, a daylighting apparatus includes a tube having a sidewall with a reflective interior surface, an at least partially transparent light collector with one or more light turning elements, and a light reflector positioned to reflect daylight into the light collector. The one or more light turning elements can turn direct and indirect daylight into the tube so that it is available to illuminate the building. In some embodiments, the tube is disposed between the light collector and a diffuser positioned inside a target area of a building. In certain embodiments, the tube is configured to direct at least a portion of the daylight transmitted through the light collector towards the diffuser.

Claims

1. A daylighting apparatus configured to direct natural daylight into an interior of a building, the apparatus comprising:

an at least partially transparent light-collecting assembly comprising a sidewall portion and a horizontal collector base aperture; and

a light turning assembly comprising a prismatic pattern positioned and configured to turn light transmitted through the at least partially transparent light-collecting assembly towards the collector base aperture, wherein the light turning assembly has a height and a circumference;

wherein the prismatic pattern comprises grooves that are defined by opposed faces, wherein the grooves comprise faces of varying angles, wherein the angles of the faces vary at different points along the circumference of the light turning assembly;

wherein the daylighting apparatus is configured to provide natural illumination to the interior of the building when the daylighting apparatus is installed on a roof of the building and when the daylighting aperture is aligned with an opening formed in a roof of the building.

2. The daylighting apparatus of claim 1, further comprising a reflector positioned and configured to reflect natural daylight towards the light turning assembly, wherein the reflector is curved in one or more dimensions.

3. The daylighting apparatus of claim 1, further comprising a reflector positioned and configured to reflect natural daylight towards the light turning assembly, wherein the reflector is planar.

4. The daylighting apparatus of claim 1, further comprising a reflector positioned and configured to reflect natural daylight towards the light turning assembly, wherein the reflector is supported by one or more support legs configured to raise a lower edge of the reflector a distance above the roof of the building when the reflector is installed on the building.

5. The daylighting apparatus of claim 1, further comprising a reflector positioned and configured to reflect natural daylight towards the light turning assembly, wherein the reflector comprises one or more optical elements configured to alter an angle of reflection of at least a portion of light that strikes the reflector.

6. The daylighting apparatus of claim 5, wherein the one or more optical elements comprises a prismatic element.

7. The daylighting apparatus of claim 6, wherein the reflector comprises a first portion having a first prismatic element, and a second portion having a second prismatic element, wherein the first prismatic element and second prismatic element have different light-turning characteristics.

8. The daylighting apparatus of claim 1, further comprising a reflector positioned and configured to reflect natural daylight towards the light turning assembly, wherein the reflector comprises a plurality of segments.

9. The daylighting apparatus of claim 1, further comprising a reflector positioned and configured to reflect natural daylight towards the light turning assembly, wherein the reflector is configured to tilt forward and/or backward.

10. The daylighting apparatus of claim 1, further comprising a reflector positioned and configured to reflect natural daylight towards the light turning assembly, wherein the reflector is substantially parabolically-shaped along at least one axis of curvature.

11. The daylighting apparatus of claim 10, wherein a cross-sectional center of the light-collecting assembly is positioned at a focus point of the parabolically-shaped reflector.

12. The daylighting apparatus of claim 1, further comprising a reflector positioned and configured to reflect natural daylight towards the light turning assembly, wherein the reflector is configured to rotate about a first axis of rotation.

13. The daylighting apparatus of claim 12, wherein the first axis of rotation is located substantially at the center of the light-collecting assembly.

14. The daylighting apparatus of claim 12, wherein the reflector is configured to rotate about at least a second axis of rotation.

15. The daylighting apparatus of claim 12, wherein the reflector is configured to automatically rotate to substantially track a solar azimuth angle.

16. The daylighting apparatus of claim 1, wherein the light turning assembly comprises a prismatic element.

17. The daylighting apparatus of claim 1, wherein the light-collecting assembly comprises a vertical portion and a top cover portion.

18. The daylighting apparatus of claim 17, wherein at least one of the vertical portion or the top cover portion comprises a prismatic element.

19. The daylighting apparatus of claim 17, further comprising a prismatic film disposed within the vertical portion of the light-collecting assembly.

20. The daylighting apparatus of claim 17, wherein the top cover portion comprises a plurality of segments, wherein each of the plurality of segments has a different outside surface angle.

21. The daylighting apparatus of claim 17, wherein the top cover portion comprises a single exterior segment having a substantially unvarying slope.

22. The daylighting apparatus of claim 17, wherein the top cover portion comprises a single exterior segment having a substantially varying slope.

23. The daylighting apparatus of claim 1, wherein the angles of the faces vary at different points along the height of the light turning assembly.

24. The daylighting apparatus of claim 1, wherein the prismatic pattern achieves a more constant light output over the course of the day.

25. The daylighting apparatus of claim 1, wherein the grooves are oriented at a nonzero angle with respect to horizontal.

26. The daylighting apparatus of claim 1, wherein the grooves have a flat or curved cross-sectional shape.

27. A method of directing natural daylight into an interior of a building, the method comprising:

transmitting natural daylight through a sidewall of a light-collecting apparatus; and

turning the natural daylight using a light turning assembly towards a horizontal daylighting aperture such that a substantial portion of the natural daylight is available for illuminating the interior of the building, the light turning assembly having a height and a circumference;

wherein the light turning assembly comprises grooves that are defined by opposed faces, wherein the grooves comprise faces of varying angles, wherein the angles of the faces vary at different points along the circumference of the light turning assembly.

28. The method of claim 27, further comprising reflecting natural daylight using a reflector towards the sidewall of the light-collecting apparatus and automatically positioning the reflector such that an apex of the reflector generally tracks a solar azimuth angle during daylight hours.

29. The method of claim 27, wherein the grooves are oriented at a nonzero angle with respect to horizontal.

30. A daylighting apparatus for providing natural light to the interior of a building, the apparatus comprising:

a transparent light-collecting assembly; and

a light turning assembly having a height and a circumference, wherein the light turning assembly comprises grooves that are defined by opposed faces, wherein the grooves comprise faces of varying angles, wherein the angles of the faces vary at different points along the circumference of the light turning assembly.

31. The daylighting apparatus of claim 30, wherein the grooves are oriented at a nonzero angle with respect to horizontal.

32. A daylighting apparatus for providing natural daylight to the interior of a building, the apparatus comprising:

a daylight collector defining a daylighting aperture configured to be positioned substantially horizontally or substantially parallel to a plane of a roof of the building surface when the daylighting apparatus is installed on the building;

and

a light turning optical element configured to turn daylight transmitted through the daylight collector towards the daylighting aperture, wherein the light turning optical element has a height and a circumference;

wherein the light turning optical element comprises grooves that are defined by opposed faces, wherein the grooves comprise faces of varying angles, wherein the angles of the faces vary at different points along the circumference of the light turning optical element.

33. The apparatus of claim 32, further comprising further comprising a reflector positioned and configured to reflect daylight towards the daylight collector and a tracking system configured to turn the reflector such that an apex of the reflector generally tracks a solar azimuth angle during daylight hours.

34. The apparatus of claim 32, further comprising a reflector positioned and configured to reflect daylight towards the daylight collector, wherein the reflector is configured to reflect daylight into the daylighting aperture such that reflected daylight is directed through a surface extending upwardly from at least half of a perimeter of the daylighting aperture.

35. The apparatus of claim 34, wherein the surface extends upwardly from at least 58% of the perimeter of the daylighting aperture.

36. The apparatus of claim 32, further comprising a reflector positioned and configured to reflect daylight towards the daylight collector, wherein the reflector has a luminous reflectance greater than or equal to about 95% when measured with respect to CIE Illuminant D₆₅.

37. The apparatus of claim 32, wherein the light turning optical element comprises a prismatic film positioned to refract light passing through the daylight collector.

38. The apparatus of claim 32, wherein the light turning optical element comprises a reflector positioned to reflect light passing through the daylight collector.

39. The apparatus of claim 32, wherein the grooves are oriented at a nonzero angle with respect to horizontal.