WO2003081300A1

WO2003081300A1 - Led acrylic conduit

Info

Publication number: WO2003081300A1
Application number: PCT/US2002/007929
Authority: WO
Inventors: William J. Grothe; Jianli Ren; Paul E. Robbins; Peter Mcnicol
Original assignee: Lumenyte International Corporation
Priority date: 2002-03-16
Filing date: 2002-03-16
Publication date: 2003-10-02
Also published as: AU2002252362A1

Abstract

A vehicle exterior lighting assembly having an acrylic optical conduit within which light dispersing elements are arrayed which when illuminated by an LED light source produce uniform, well-defined and attractive accent lighting. The lighting assembly includes an acrylic optical conduit contained within an assembly which positions the LED for efficient illumination of the optical conduit, and provides an assembly which is resistant to entry of debris and excessive moisture.

Description

LED ACRYLIC CONDUIT

Technical Field

The present invention relates to improvements in the field of fiber optic accessory lighting in which the appearance and visibility of light emitted along a length of linear acrylic fiber optical conduit, illuminated by an LED light source, is rendered more uniform and well defined.

Background Art Lighting assemblies for vehicle exterior accent lighting typically employ standard incandescent bulbs or soft fiber optic conduits illuminated by a variety of light sources. Incandescent bulbs typically have a relatively limited service life and therefore require more frequent maintenance than longer lived light sources such as LED's. In the field of vehicle accent lighting, fiber optic conduits typically have "notches" cut into the conduit, which "notches" serve to reflect light from the light source through the side of the conduit opposite the "notch." The resulting lighting typically has a "beaded" appearance, and the intensity of the light emanating from the fiber optic conduit tends to diminish rapidly outside a relatively narrow angular field of view. The present invention is directed to solving these problems by providing a long lived relatively high intensity LED light source, together with a hard acrylic optical conduit in which is embedded light dispersing elements which provide a linear rather than "beaded" visual appearance in which the light intensity does not vary perceptibly with the angle of view.

Disclosure of Invention In its several embodiments, the present invention improves the appearance and visibility of light emitted from a linear optical conduit accessory lighting assembly illuminated by an LED used as accent lighting mounted on the exterior body panels of vehicles.

In a first preferred embodiment, a hard acrylic optical conduit containing an array of longitudinal light dispersing elements is placed within a transparent acrylic lens assembly adapted to receive and precisely position an LED light source. The lens assembly, in turn is mounted within a cover having an opening conformed to the size and shape of the lens assembly through which a portion of the lens assembly containing the optical conduit projects. A base adapted to the size and shape of the cover and upon which the LED and associated circuitry is mounted, is removably and mechanically affixed to the cover. When illuminated by the LED light source, the acrylic optical conduit emits light along its length with contrastingly bright lines of light from each internal light dispersing element. Further, when illuminated the light emitted from the optical conduit is visible over an angular range of more than 180° degrees as measured in a plane perpendicular to the longitudinal axis of the optical conduit. In a second preferred embodiment, a reflective coating or layer applied to the end of the optical conduit distal from the LED light source, or a mirror positioned proximate to said distal end, functions to reflect light back along the optical conduit to increase the intensity and uniformity of the light emitted along the length of the optical conduit.

In a third preferred embodiment, an LED light source may be used at both ends of the acrylic optical conduit to further enhance the intensity and uniformity of the light emitted.

In all preferred embodiments of the present invention, the preferred light source is a recently developed relatively powerful LED, such as those manufactured by Hewlett- Packard, Everlight or Nichia. The Nichia High Power NSPW 500 BS is the most preferred LED for use in any present invention.

Various cross-sectional shapes for the pattern of light dispersing elements within the conduit may be used. In any present invention a plurality of light dispersing elements arrayed in a circular cross-section pattern is preferred.

Brief Description Of The Drawings

Other objects and advantages of the invention will become apparent from the forgoing detailed description taken in connection with the accompanying drawings, in which:

Figure 1 is a perspective view of the LED acrylic optical conduit assembly.

Figure 2 is an exploded perspective view of the Figure 1 assembly disassembled. Figure 3 is a top, partially disassembled perspective view of a portion of the lens and LED assemblies of the present invention.

Figure 4 is a cross-sectional view through the Figure 1 assembly of the present invention.

Figure 5 is a cross-sectional view of the present invention in the plane of the LED receptacle.

Best Mode for Carrying Out the Invention To illustrate and further describe the embodiments of the present invention, reference will be made to Figures 1-5.

Figure 1 is a perspective view of the LED acrylic conduit assembly 10 fully assembled. With reference to Figure 2 the cover 20 of assembly 10 includes top end portion 28 and bottom end portion 26 having similar and generally uniform radii of curvature in planes orthogonal to the longitudinal axis of cover 20. Cover 20 has a generally crescent shaped cross section, as shown in Figure 5. Disposed in cover 20 at the apex of its crescent shaped cross section is a longitudinal cover opening 22 which extends along the longitudinal axis of cover 20. In the first preferred embodiment of the present invention, longitudinal cover opening 22 is disposed centered midway between bottom end 26 and top end 28 of cover 20. Perimeter wall 24 is formed around the perimeter of longitudinal cover opening 22. Preferably cover 20 is fabricated of moldable polymeric material, although other materials having equivalent or greater rigidity and strength may be used.

With reference to Figures 1-4, lens 32 is fabricated of transparent polymeric material. Preferably lens 32 is fabricated of Mitsubishi IR-D-70 acrylic or its equivalent.

Lens 32 is adapted to snugly friction fit within longitudinal cover opening 22. Lens 32 includes longitudinal lens cavity 64 adapted to receive optical conduit 40. Lens flange 34 and 35 extend longitudinally along lens cavity 64.

With reference to Figures 2-5, front surface 46 of base 44 includes a base cavity 66 adapted to conform with the size and shape of lens 32 including lens flanges 34 and 35.

The portion of lens 32 bounding the opening of lens cavity 64 including flanges 34 and 35 sealingly contact recessed surface 68 of base cavity 66, to resist entry of debris and moisture into lens cavity 64. Preferably base 44 is fabricated of moldable polymeric material, although other materials having equivalent or greater rigidity and strength may be used. With reference to Figures 2, 3 and 5, lens 32 includes LED positioning receptacle

36. LED 58 is positioned in LED positioning cavity 38 of positioning receptacle 36. LED 58 and LED associated circuitry 60 is positioned on front surface 46 of base 44 near the top end 62 of base 44. Base 44 includes mounting collars 50 and 54 which surround mounting holes 52 and 56, respectively. The conduit assembly 10 is mounted to a substrate surface by means of screws or other mechanical fasteners through mounting holes

52 and 56.

With respect to Figures 2-5, optical conduit 40 is adapted to snugly friction fit at the full depth of lens cavity 64. It will be understood by one skilled in the art that acrylic optical conduit 40 may also be maintained in position in lens cavity 64 by means of projections from the surface of lens cavity 64 or by means of other mechanical fasteners or heat or chemical bonding. Acrylic optical conduit 40 includes one or more light dispersing elements 42 arrayed in a predetermined pattern within the matrix of optical conduit 40. Light dispersing elements 42 extend along the length or longitudinal axis of conduit 40. In a first preferred embodiment, 15 light dispersing elements 42 are arrayed in a radially symmetric circular pattern centered upon the central longitudinal axis of conduit 40. Each light dispersing element 42 extends parallel to the longitudinal axis of conduit 40. In the first preferred embodiment of conduit 40, each light dispersing element 42 has an elliptical cross section as measured in a plane perpendicular to the longitudinal axis of conduit 40. The minor axis of the elliptical cross section of each light dispersing element 42 is aligned with a radial extending orthogonally from the central longitudinal axis of conduit 40. It will be understood by one skilled in the art that the number of light dispersing elements 42 included within optical conduit 40 may be varied, as may the patterns in which the light dispersing elements 42 are arrayed. It will similarly be understood by one skilled in the art that the size and cross-sectional shape of each light dispersing element 42 may also be varied. With reference to Figures 2, 4 and 5, base 44 is adapted to the size and shape of cover 20 such that cover 20 containing lens 32 and optical conduit 44 snugly friction fits over base 44. Cover 20, lens 32 and optical conduit 40 are removably affixed to base 44 by coupling between cover tab 82 (not shown) and base groove 84 (not shown), positioned within the top end 28 of cover 20 and top end 62 of base 44, respectively. The cover 20 containing lens 32 and acrylic optical conduit 40 is further removably affixed to base 44 by means of screw 86 (not shown) inserted through cover screw opening 30 in bottom end 26 of cover 20 to engage base assembly screw receptacle 48. Cavity 78 of cover 20 is adapted to receive LED positioning receptacle 36 of lens 32, upon assembly of lens 32 and cover 20. When assembled, LED 58 is positioned within LED positioning cavity 38 of lens 32 such that LED 58 is adjacent acrylic optical conduit 40 and emits light into conduit 40 when powered on by an external power supply. When LED acrylic conduit assembly 10 is fully assembled, lower surface 72 of perimeter wall 24 of cover opening 22 contacts and applied compression force to upper surface 70 of flanges 34 and 35 of lens 32 which serves to maintain a seal between lens 32 and base 44.

With respect to Figure 5, annular light attenuating element 80 positioned within LED positioning cavity 38 proximate to acrylic optical conduit 40 functions to collimate light emitted from LED 58 and to improve uniformity of illumination of optical conduit 40, by reducing direct emission of light from LED 58 through lens 32. With reference to Figures 4 and 5, LED acrylic conduit assembly 10 includes mounting gasket 74 adapted to the size and shape of base 44. Mounting gasket 74 is affixed to base 44 and cover 20 by conventional adhesive suitable for use in an outdoor environment. Mounting gasket 74 includes gasket mounting holes 88 and 90 (not shown) which align with mounting holes 52 and 56, respectively of base 44. The mounting gasket 74 includes gasket slot 76 which extends longitudinally a predetermined distance. Gasket slot 76 provides a channel for electrical wiring extending from the substrate surface to the LED circuitry 60 through wiring opening 92 (not shown) in base 44.

In a first preferred application the present invention is affixed in a generally vertical orientation to the exterior of a vehicle to provide pleasant and attractive accent lighting. A second preferred embodiment of the present invention is described by reference to Figures 1 and 2. In a second preferred embodiment a reflective layer 94 (not shown) is applied to the distal end 100 of optical conduit 40. Alternatively, a mirror 96 (not shown) is positioned proximate to distal end 100 of optical conduit 40. Reflective layer 94 or mirror 96 function to reflect light reaching the distal end 100 of conduit 40 from LED 58 back into conduit 40 to enhance uniformity and intensity of illumination emitting from conduit assembly 10.

A third preferred embodiment of the present invention incorporates two LED light sources positioned at opposite ends conduit 40. In the third preferred embodiment, the opposite ends of lens 32 are symmetric and each such end includes an LED positioning receptacle 36 and LED positioning cavity 38 together with light attenuating elements 80. Similarly, in a third preferred embodiment, cover 20 includes cavity 78 near each end of cover opening 22 to accept LED positioning receptacles 36. Also in a third preferred embodiment, a base 44 includes an LED 58 and LED circuitry 60 adjacent to mounting collar 50 in similar configuration, including wiring opening 92, as is shown with respect to mounting collar 54 in Figure 3. In a third preferred embodiment, gasket slot 76 extends between and joins gasket mounting holes 88 and 90 (not shown). The two LED light sources 58 of the third preferred embodiment function to provide increased intensity and uniformity of illumination emitting from LED acrylic conduit assembly 10.

With respect to each embodiment of the present invention it will be noted by one of ordinary skill in the art that lens 32 and optical conduit 40 may be formed as a single integrated structure. However, for ease and economy in manufacture, an assembly of separate components is preferred.

While the present invention has been described in connection with what are present considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but to the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit of the invention, which are set forth in the appended claims, and which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures.

Claims

What is claimed is:

1. a lighting assembly comprising: a housing including a transparent lens; a light conduit in optical communication with said lens disposed within said housing; at least one light source in optical communication with said light conduit disposed within said housing; at least one light dispersing element disposed within said light conduit.

2. The lighting assembly of claim 1 wherein: said housing is resistant to entry of debris and moisture.

3. The lighting assembly of claim 1 wherein: said light conduit contains a plurality of light dispersing elements.

4. The lighting assembly of claim 1 further including: orthogonal length, width and height dimensions; wherein said length dimension is the greatest.

5. The lighting assembly of claim 1 wherein: said light conduit has orthogonal length, width and height dimensions; wherein said length dimension is the greatest; and said light conduit contains a plurality of light dispersing elements.

6. The lighting assembly of claim 5 wherein: said plurality of light dispersing elements are arrayed in a predetermined pattern.

7. The lighting assembly of claim 5 wherein: said plurality of light dispersing elements are arrayed in a circular pattern as viewed in a plane orthogonal to said length dimension of said light conduit.

8. The lighting assembly of claim 5 wherein: said plurality of light dispersing elements are arrayed in a circular pattern as viewed in a plane orthogonal to said length dimension of said light conduit; and the number of said light dispersing elements is 15.

9. The lighting assembly of claim 5 wherein: said plurality of light dispersing elements each extend along said length dimension of said light conduit.

10. The lighting assembly of claim 1 wherein: said housing is adapted for mounting to a surface.

11. The lighting assembly of claim 1 wherein: said housing is adapted for mounting to the exterior of a vehicle.

12. The lighting assembly of claim 5 wherein: said plurality of light dispersing elements each have a cross-sectional shape; and said light dispersing elements each have substantially the same cross- sectional shape.

13. The lighting assembly of claim 5 wherein: said plurality of light dispersing elements each have a cross-sectional size; and said light dispersing elements each have substantially the same cross- sectional size.

14. The lighting assembly of claim 5 wherein: each said light dispersing element has a predetermined cross-sectional shape.

15. The lighting assembly of claim 5 wherein: each said light dispersing element has a predetermined cross-sectional size.

16. The lighting assembly of claim 5 wherein: each said light dispersing element has an elliptical cross-section in a plane orthogonal to said length dimension of said light conduit.

17. The lighting assembly of any of claims 6, 7, 8, 9, 12, 13, 14, 15 or 16 wherein: said housing is adapted for mounting to a surface.

18. The lighting assembly of any of claims 6, 7, 8, 9, 12, 13, 14, 15 or 16 wherein: said housing is adapted for mounting to the exterior of a vehicle.