Edge-lit luminaire with capability for secondary services - Patent Application 20070122967

Abstract

To provide an edge lighting-type lighting apparatus having a capability for secondary service.SOLUTION: A lighting apparatus is disclosed in the present invention. The lighting apparatus includes a light emitting diode (LED) engine including a plurality of LEDs for emitting visible light, and a waveguide pipe. The plurality of LEDs surround the waveguide pipe and emit the visible light in the direction of the waveguide pipe. The lighting apparatus also includes a secondary element for providing secondary service. The lighting apparatus includes a housing which constitutes a cavity, the LED engine and the waveguide pipe are positioned in the cavity in the vicinity of the front part of the lighting apparatus, and the secondary element is positioned in the cavity toward the rear part of the lighting apparatus.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates generally to lighting fixtures, and more particularly to lighting fixtures that include a light-emitting element and at least one other element that provides a secondary service, both of which are contained within a housing of the lighting fixture. [Background technology]

[0002] Light emitting diode (LED) based lighting systems can offer several energy and reliability advantages over other types of lighting systems, such as incandescent or fluorescent lighting. Thus, LED based lighting systems are increasingly being used to replace other existing lighting technologies. Furthermore, it should be appreciated that LED based lighting systems are also being used as other components, such as in home automation systems.

[0003] Automation systems are used to control various systems typically found in homes and office buildings, such as lights, heating, safety systems, and household appliances. Some examples of appliances that can be controlled by automation systems include washers, dryers, ovens, and refrigerators. Indeed, lighting fixtures often include light-emitting elements, such as LED light engines, and other elements that provide other functions. For example, lighting fixtures may include speakers that generate sound or microphones that detect a user's voice or other sounds.

[0004] Difficulties are often encountered when attempting to provide different functions within a single lighting fixture. This is because lighting fixtures typically have standard dimensions, thus limiting the amount of space available to accommodate various components. Furthermore, the additional components can often interfere with the ability to emit light in a manner that is not only effective but also aesthetically appealing. Providing other functions within a lighting fixture also presents challenges. For example, the sound quality or level of a speaker may be compromised in order to meet the lumen requirements of the lighting fixture. [Brief explanation of the drawings]

[0005] [Figure 1] FIG. 1 is a cross-sectional perspective view of the disclosed lighting fixture. [Figure 2] FIG. 2 is an exploded view of the lighting fixture shown in FIG. 1. [Figure 3] FIG. 2 is an enlarged view of a portion of the lighting fixture shown in FIG. 1. [Figure 4] FIG. 2 is another perspective view of the disclosed lighting fixture. DETAILED DESCRIPTION OF THE INVENTION

[0006] The following detailed description illustrates the general principles of the invention, examples of which are additionally illustrated in the accompanying drawings, where like reference numbers indicate identical or functionally similar elements.

[0007] FIG. 1 is a cross-sectional perspective view of an exemplary lighting fixture 10. Lighting fixture 10 includes a bezel 20, a waveguide 22, a secondary element 26, a secondary element holder 28, a light-emitting diode (LED) engine 30, a first driver board 32, a driver board holder 34, a second driver board 36, a housing 40, an end cap or cover 42, and one or more mounting features, such as a mounting spring. Although lighting fixture 10 shown in FIG. 1 represents a downlight, the embodiment of FIG. 1 is merely exemplary in nature. For example, in other embodiments, lighting fixture 10 may be a parabolic aluminum reflector (PAR) type lighting fixture or a bulge reflector (BR) type lighting fixture.

[0008] In addition to producing light, lighting fixture 10 also includes a secondary element 26, which is used to provide another, secondary service in addition to producing light. In the non-limiting embodiment as described, secondary element 26 is a speaker for producing sound. For example, in other embodiments, secondary element 26 may be a microphone or a motion detector.

[0009] The housing 40 defines a cavity 50 shaped to accommodate the secondary element 26, secondary element holder 28, LED engine 30, first driver board 32, driver board holder 34, and second driver board 36. In a non-limiting embodiment as shown in FIG. 1 , the housing 40 includes a heat sink 46 made of a thermally conductive metal. The heat sink 46 is flush with the interior surface of the housing 40. In another embodiment, the housing 40 is made of a material that is an electrical conductor, allowing radio frequency (RF) signals to pass through it, such as a thermally conductive plastic. The housing 40 defines a first end portion 52 and a second end portion 54. The first end portion 52 of the housing 40 defines a first opening 56 of the housing 40, and the second end portion 54 of the housing 40 defines a second opening 58 of the housing 40. As can be seen in FIG. 1, a portion 41 of the housing 40 may have a generally frusto-conical profile, with a first opening 56 of the housing 40 being larger in size than a second opening 58 .

[0010] In the non-limiting embodiment as shown, a first end portion 52 of the housing 40 is attached to the bezel 20, and a second end portion 54 of the housing 40 is attached to the cover 42. The bezel 20 may be attached to the first end portion 52 of the housing 40 by a snap-fit ​​engagement. However, it should be understood that the bezel 20 and the housing 40 are not limited to a snap-fit ​​engagement, and that other fastening techniques may be used to attach the bezel 20 to the housing 40. Furthermore, in alternative embodiments, the bezel 20 and the housing 40 may be integrated into one piece. The cover 42 may be used to close and seal the second opening 58 in the housing 40.

[0011] FIG. 2 is an exploded view of the lighting fixture 10 shown in FIG. 1. Referring now to both FIGS. 1 and 2, the cover 42 may include one or more positioning features 60 for engaging and positioning the second driver board 36. The second driver board 36 may include the LED engine 30 and various power electronics 62 required for electrical operation of the lighting fixture 10. The driver board holder 34 may include one or more legs 70 that, when assembled, protrude in a direction toward the second end portion 54 of the lighting fixture 10 and the cover 42. The legs 70 of the driver board holder 34 may Engage the driver board 36 It can act as a locating pin or feature used to mount it in place within cavity 50 of housing 40 .

[0012] The driver board holder 34 may also define a ledge 72, which defines a recessed surface 74 (corresponding to the exterior of the holder 34 shown in FIG. 2 ) upon which the first driver board 32 may be seated. The first driver board 32 may be a printed circuit board (PCB) and may include an antenna (not shown), such as a trace antenna. However, those skilled in the art will understand that the present disclosure should not be limited to trace antennas and PCBs. In one embodiment, the first driver board 32 may be configured to receive short-range RF signals, such as Bluetooth® signals conforming to the Institute of Electrical and Electronics Engineers (IEEE) Standard 802.1.5.

[0013] Referring to FIG. 1 , secondary element 26 includes a first end portion 76 and a second end portion 78. First end portion 76 of secondary element 26, shown as a speaker, is seated on a front surface 80 of driver board holder 34. Now referring to both FIG. 1 and FIG. 2 , secondary element holder 28 defines a first end portion 82, a second end portion 84, and an axially extending cavity 86 along central axis AA of lighting fixture 10. First end portion 82 of secondary element holder 28 includes one or more retention flanges 90. As can be seen in FIG. 1 , flanges 90 of secondary element holder 28 can engage holder 28 with retention features 92 located along interior surface 48 of housing 40.

[0014] Second end portion 84 of holder 28 defines a flange 96 that extends inwardly relative to axis AA of lighting fixture 10. As seen in FIG. 1 , flange 96 defines an opening 100 that is smaller in size than second end portion 78 of secondary element 26. Thus, a rear surface 98 of flange 96 of secondary element holder 28 holds secondary element 26 in place within housing 40 of lighting fixture 10. For example, in the embodiment shown, lighting fixture 10 is a downlight. Thus, when the downlight is installed in a building, end cap 42 is positioned on top or at the upper end of lighting fixture 10. When the downlight is installed, flange 96 of secondary element holder 28 prevents secondary element 26 from moving downward and contacting waveguide 22.

[0015] The lighting fixture 10 is an edge-lit lighting fixture. That is, the LED engine 30 surrounds the waveguide 22 in the plane of the waveguide, i.e., surrounding the side edges of the waveguide 22 relative to the central axis AA of the lighting fixture. The waveguide 22 is made of a material that has properties that allow the light generated by the LED engine 30 to be used to illuminate an entire surface 102 (FIGS. 1 and 4). An advantage of using an edge-lit device is reduced cost, since fewer LEDs are typically required to produce the same lumen output. Referring to FIGS. 1 and 3, the LED engine 30 includes a backing material 104 and a plurality of LEDs 106 mounted on the backing material 104. The backing material 104 may optionally be a flexible material. In particular, the backing material 104 may be formed as a strip, which may be bent into an annular or ring-like shape, as seen in FIG. 3. Thus, the LED light engine 30 may extend completely around the perimeter 100 of the waveguide 22. In other words, the plurality of LEDs 106 surrounds the waveguide 22 and transmits visible light in a direction toward the waveguide 22.

[0016] Referring now to FIG. 4 , the waveguide 22 may also be referred to as a light guide. The waveguide 22 is used to collect light generated by multiple LEDs 106 and direct the light to a front surface 102 of the waveguide 22 to provide illumination. The waveguide 22 may include multiple polarizing elements (not shown), which are also referred to as microstructures or three-dimensional elements. In one embodiment, the polarizing elements are prismatic cavities formed along the length of the waveguide 22 and are used to illuminate the entire surface 102 of the waveguide 22. The polarizing elements are distributed along the front surface 102 of the waveguide 22.

[0017] The waveguide 22 may define a plurality of holes 112 distributed in a predetermined pattern along the front surface 102 of the waveguide 22. In the embodiment as shown, the holes 102 allow sound generated by the secondary element 26, shown as a speaker (FIGS. 1 and 2), to be transmitted to the environment. The holes 112 may be arranged in a star-shaped pattern, in which the holes 102 are arranged to radiate outward from a central point along the front surface 102 of the waveguide 22. However, it should be understood that the embodiment of FIG. 4 is merely exemplary in nature, and the holes 112 may be arranged in a variety of patterns and shapes.

[0018] It should be appreciated that the holes 112 are positioned to provide acceptable sound quality and meet any light output or lumen requirements, as well as be aesthetically appealing. In other words, the holes 112 are positioned to create a light pattern that is deemed visually appealing to a consumer.

[0019] Referring generally to the drawings, the disclosed lighting assembly provides at least one other, or secondary, service to the consumer. For example, in the embodiment shown, the secondary service is a speaker for emitting sound. An LED light engine is positioned around the waveguide and directs light toward the waveguide. Edge-lit lighting fixtures require less packaging space than traditional board-type LED light engines, which are typically mounted around the center of the fixture. Thus, edge-lit LEDs allow for sufficient packaging space for components associated with the secondary service. In other words, the edge-lit LED shape increases the packaging space available to accommodate the speaker. Furthermore, the sound quality and level of the speaker are not compromised to meet the lumen requirements of the lighting fixture.

[0020] Although the forms of the apparatus and method described herein constitute preferred embodiments of the invention, it should be understood that the invention is not limited to these forms of the apparatus and method and that modifications can be made without departing from the scope of the invention. [Explanation of symbols]

[0021] 10 Lighting fixtures 20 bezel 22 Waveguide 26 Secondary Elements 28 Secondary element holder 30 LED Engine 32 First Driver Board 34 Driver board holder 36 Second Driver Board 40 Housing 42 End cap or cover 46 Heatsink 50 cavities 104 Backing material 106 LED

Claims

1. 1. A lighting fixture, comprising: a light emitting diode (LED) engine including a plurality of LEDs configured to emit visible light; a housing defining a cavity, the LED engine and waveguide being positioned within a first end portion of the housing comprising a front portion of the lighting fixture; the plurality of LEDs of the light emitting diode (LED) engine are configured to circumferentially surround a side edge of the waveguide relative to a central axis of the lighting fixture and to emit visible light in a direction toward the waveguide; a secondary element configured to provide secondary services, the secondary element being disposed aft of the waveguide and positioned within the cavity between the first end portion of the housing and a second end portion of the housing that includes a rear of the lighting fixture; the waveguide includes a plurality of holes through a front surface thereof, the plurality of holes allowing sound to be transmitted from the secondary element to an environment of the lighting fixture or to be received by the secondary element from the environment of the lighting fixture; the driver board holder includes a ledge defining a recessed surface on which the first driver board rests, the driver board holder including one or more legs projecting in a direction toward the second end portion of the housing, the one or more legs engaging with the second driver board to mount the second driver board within the cavity.

2. 10. The lighting fixture of claim 1, wherein the waveguide includes a plurality of polarizing elements including prismatic cavities formed along the length of the waveguide, the polarizing elements configured to illuminate the entire front surface of the waveguide in response to receiving visible light from the plurality of LEDs.

3. 10. The lighting fixture of claim 1, wherein the secondary element comprises a microphone or a speaker.

4. The lighting fixture according to claim 1 , wherein the lighting fixture is a downlight.

5. 10. The lighting fixture of claim 1, wherein the LEDs of the LED engine are mounted on a backing material, the backing material being shaped as an annular ring extending around a circumference of the waveguide.

6. 10. The lighting fixture of claim 1, wherein the first end portion of the housing includes a heat sink made of a thermally conductive metal conforming to an interior surface of the housing.

7. the lighting fixture includes first and second driver boards positioned with the cavity between the second end portion and the secondary element; a driver board holder interposed between the first and second driver boards and the secondary element, the secondary element resting against a front surface of the driver board holder; The lighting fixture of claim 1 further comprising a secondary element holder interposed between the secondary element and the waveguide.

8. 8. The lighting fixture of claim 7, wherein the front surface of the driver board holder defines a ledge, the ledge defining a recessed surface upon which the first driver board rests.

9. 8. The lighting fixture of claim 7, wherein the first driver board includes an antenna configured to receive short-range radio frequency (RF) signals.

10. 8. The lighting fixture of claim 7, further comprising an end cap attached to the second end portion of the housing, the end cap including a locating feature that engages the second driver board.

11. 8. The lighting fixture of claim 7, wherein the secondary element holder includes a first end portion including one or more retention flanges that engage retention features located along an interior surface of the housing.

12. 12. The lighting fixture of claim 11, wherein the secondary element holder includes a second end portion positioned forward of the first end portion, the second end portion including an inwardly extending flange defining a smaller opening than the second end portion.

13. 13. The lighting fixture of claim 12, wherein the secondary element holder is seated between a front surface of the driver board holder and a rear surface of the inwardly extending flange.

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