Patent Application
20140177219
Existing ingress protected lighting systems (e.g., outdoor light fixtures) may have large profiles. For example, vapor tight light fixtures may employ bulky housings and/or lenses which may be susceptible to becoming accidentally or intentionally damaged. The outdoor light fixtures may employ large light generating sources (e.g., fluorescent lights) to provide a proper amount of light. As such, the outdoor light fixtures employ bulky housings and lenses that house the large light sources to meet ingress protection requirements. For example, the outdoor vapor tight light fixtures employ housings and lenses capable of providing protection against the intrusion of solid objects, such as, hands (e.g., vandal-protected), accidental contact, dust, water, ice, etc.
Further, existing ceiling mounted ingress protected lighting systems typically employ straight down optical packages. For example, existing ingress protected lighting systems have light generating sources fixed in housings that shine substantially straight out (i.e., perpendicular to) the ceiling mounted housing. The straight down optical packages typically employ heatsinks, separate from the housing and mounted inside the housing to dissipate heat from the light generating sources fixed in the housing.
One challenge in using existing ingress protected lighting systems is that they do not provide for controlling the distribution of the light to target locations. For instance, existing ingress protected lighting systems installed on a parking garage ceiling generally direct light in a single direction.
Accordingly, there remains a need for improved ingress protected lighting systems.
The detailed description is set forth with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The use of the same reference numbers in different figures indicates similar or identical items.
Low profile light-emitting diode (LED) fixtures for outdoor and/or indoor use are described. A low profile LED fixture is configured to providing a degree of ingress protection. For example, the low profile LED fixture may be configured to provide a degree of ingress protection defined by a standards organization (e.g., International Electrotechnical Commission (IEC), National Electrical Manufactures Association (NEMA), Underwriters Laboratories (UL), Canadian Standards Association (CSA), United States Military Standard, etc.). A degree of ingress protection defines a degree of protection provided against the intrusion of objects in enclosures.
The low profile LED fixture employs a plurality of LEDs, enabling a thin profile in comparison to existing ingress protected lighting fixtures. The low profile LED fixture includes a housing arranged to dissipate heat from the plurality of LEDs fixed to the housing. The low profile LED fixture further employs customizable reflectors, enabling a controlled distribution of light. As a result, low profile LED fixtures according to this disclosure are ingress protected, provide thermal management for the plurality of LEDs, and provide customizable light control.
Because the low profile LED fixture has a compact profile, the low profile LED fixture may be installed on low ceilings (e.g., parking garage ceilings). The low profile LED fixture installed on a low ceiling provides improved vandal resistance, clean aesthetics, and little to no interruption of heating, ventilation, and air conditioning, (HVAC) systems. Further, because the low profile LED fixture utilizes LEDs, the low profile LED fixture may have a high luminous efficacy and/or efficiency compared to existing ingress protected light fixtures using fluorescent lights. In addition to providing light with less energy the LEDs have a much longer life than existing fluorescent lights. For example, the retrofit LED system may provide light for at least about 50,000 hours, 70,000 hours, 100,000 hours, or longer. In this manner, installed low profile LED fixtures are less obtrusive, and less vulnerable to impacts, while providing light with less energy (i.e., a higher luminous efficacy and/or efficiency).
Generally, a low profile LED fixture according to this disclosure has a housing that dissipates heat from a plurality of LEDs fixed to the housing via a thermal interface. The housing includes an acutely angled flange arranged around a perimeter of a base of the housing for fixing the plurality of LEDs thereto. The plurality of LEDs have a size that provides for fixing the plurality of LEDs inside the acutely angled flange. The low profile LED fixture further includes an optical reflector arranged in the housing to reflect light emitted by the LEDs fixed to the inside of the acutely angled flange.
For discussion purposes, the low profile LED fixture is described in various embodiments herein as including a plurality of LEDs fixed to a flange of a housing that dissipates heat from the plurality of LEDs. However, the plurality of LEDs may be fixed to any portion of the housing that dissipates heat from the plurality of LEDs. Further, while the low profile LED fixture is described in various embodiments herein as including LEDs, other light generating sources may be used. For example, the low profile LED fixture may include organic light-emitting diodes (OLEDs), polymer light-emitting diodes (PLEDs), phosphorescent organic light-emitting diodes (PHOLEDs) or any other suitable light source. The low profile LED fixture may use any low profile light technology suitable for providing a compact or thin profile. Further, the low profile LED fixture may be installed in any location, such as, for example, on a wall of a parking garage, a wall of a stairwell, a ceiling of a stairwell, a ceiling of a free-standing structure (e.g., a ceiling of a pavilion). Further, while the low profile LED fixture is described in various embodiments herein as having a substantially rectangular shape, other shapes are contemplated. For example, the housing may comprise a substantially curvilinear shape (e.g., round shape, half round shape, crescent shape, oval shape, etc.), triangular shape, octagonal shape, etc. For example, the housing may be substantially round and equipped with a single flange having an acute angel. The single flange may be arranged around a substantially round perimeter of a round base of the round housing, and the plurality of LEDs may be fixed to an inside of the acutely angled flange.
In some embodiments, the low profile LED fixture includes a housing having a flange arranged around a perimeter of the housing. The flange may extend in towards a middle of the perimeter of the housing and may have an acute angle. A plurality of LEDs may be fixed to an inside of the flange.
In some embodiments, the low profile LED fixture includes a base and opposing first and second flanges arranged along opposite edges of the base. The opposing first and second flanges may extend in towards a middle of the base at an acute angle. A plurality of LEDs may be fixed to an inside of the opposing first and second flanges.
In some embodiments, the low profile LED fixture includes an optical reflector arranged inside the housing. The optical reflector may be arranged to reflect light emitted by the plurality of LEDs. Alternatively, the LEDs may be fixed to a base of the housing to emit light directly out of the housing without the use of an optical reflector.
In any of the embodiments described above, the housing may be configured to dissipate heat from the plurality of LEDs fixed to the heat dissipating housing. For example, the plurality of LEDs may be fixed to the housing via a thermal interface.
Flange(s) 110(A) and 110(B) may be arranged along the perimeter 106 of the housing 104. The flange(s) 110(A) and 110(B) may extend in towards a middle 112 of the perimeter 106 of the housing 104, and have an acute angle 114 relative to a base 116 of the housing 104. The base 116 may be arranged within the perimeter 106 of the housing 104. The flange(s) 110(A) and 110(B) may oppose one another, and may be arranged along opposite edges 118(A) and 118(B) of the base 116. The opposing flange(s) 110(A) and 110(B) extending in towards a middle of the base 116 at the acute angle 114 may defining a cavity 120 of the housing 104.
The flange(s) 110(A) and 110(B) may include edge(s) 122(A) and 122(B) arranged around an inside of the flange(s) 110(A) and 110(B). The edge(s) 122(A) and 122(B) arranged around the inside of the flange(s) 110(A) and 110(B) defining an aperture 124 of the housing 104.
The LED fixture 102 may include a plurality of LEDs 126(A) and 126(B) fixed to an inside wall of the flange(s) 110(A) and 110(B). For example, the plurality of LEDs 126(A) and 126(B) may be LED strips fixed to an inside wall of the flange(s) 110(A) and 110(B) via a thermal interface. The thermal interface may be a thermal adhesive, a thermal tape, thermal grease, a thermal gel, or any other thermal interface suitable to provide for or having the effect of, dissipating heat from the plurality of LEDs 126(A) and 126(B) to the housing 104. The plurality of LEDs 126(A) and 126(B) may have a length 128 that is approximately equal to a length 130 of the flange(s) 110(A) and 110(B). Further, the plurality of LEDs 126(A) and 126(B) may have a width 132 that is approximately equal to a width 134 of the flange(s) 110(A) and 110(B). In one specific example, the width 134 of the flange(s) 110(A) and 110(B) may be about 2 inches (50 millimeters). The LEDs arranged along the strips may be spaced about 2 inches (50 millimeters) apart along the length 128 of the strips of LEDs 126(A) and 126(B). In other examples the width 134 and/or the length 128 may have dimensions larger or smaller than those described.
The LED fixture 102 may include optical reflector(s) 136(A) and 136(B). The optical reflector(s) 136(A) and 136(B) may be arranged to be fixed inside the perimeter 106 of the housing 104 opposite to the plurality of LEDs 126(A) and 126(B) fixed to an inside wall of the flange(s) 110(A) and 110(B). The optical reflector(s) 136(A) and 136(B) may have a reflective surface 138 arranged to reflect light emitted by the plurality of LEDs 126(A) and 126(B) out of the aperture 124 of the housing 104. For example, the optical reflector(s) 136(A) and 136(B) may have a substantially curvilinear cross-sectional area to control the light emitted by the plurality of LEDs 126(A) and 126(B) (discussed in detail below with regard to
The LED fixture 102 may include a lens 140. The lens 140 may be arranged to be fixed to the edge(s) 122(A) and 122(B) of the flange(s) 110(A) and 110(B). For example, the lens 140 may include edge(s) 142(A) and 142(B) configured to cooperate with the edge(s) 122(A) and 122(B) to fix the lens 140 to the housing 104. The edge(s) 142(A) and 142(B) may snap-in place with the cooperating edge(s) 122(A) and 122(B) to fix the lens 140 to the housing 104. While
The edge(s) 142(A) and 142(B) may include an 0-ring groove configured to retain O-ring(s) 144(A) and 144(B). The O-ring(s) 144(A) and 144(B) may provide a degree of ingress protection. For example, when the lens 140 is fixed (e.g., snapped-in) to the housing 104, the O-ring(s) 144(A) and 144(B) may be deformed or squished between the cooperating edge(s) 122(A), 122(B), 142(A), and 142(B), to seal the cavity 120 against foreign objects.
The housing 104 may be formed of metal, plastic, wood, and/or any other suitable material, to be installed outside and/or inside. For example, the housing 104 may be formed of sheet metal (e.g., aluminum sheet metal, or cold rolled steel (CRS), stainless steel, copper, brass, tin, nickel, titanium, etc.) having a thickness of about 0.04 inches (1 millimeter). Further, the flange(s) 110(A) and 110(B) may have a material thickness of about the same as the sheet metal thickness of the housing 104. For example, the housing 104 may be formed of 0.036 inch thick aluminum, and the flange(s) 110(A) and 110(B) may have a thickness of about 0.04 inches (1 millimeter). In the illustrated embodiment, the flange(s) 110(A) and 110(B) are shown as having the same sheet metal thickness as the housing 104 (e.g., 0.04 inches (1 millimeter)). However, the flange(s) 110(A) and 110(B) may be formed of any suitable thickness and/or shape effective to fix the lens 140 to the housing 104 and provide a degree of ingress protection. The housing 104, including the base 116 and the opposing first and second flange(s) 110(A) and 110(B) may be formed of a single unit of material. For example, the housing 104 may be formed of a single unit of sheet metal (e.g., aluminum sheet metal, or cold rolled steel (CRS), stainless steel, copper, brass, tin, nickel, titanium, etc.) having a thickness of about 0.04 inches (1 millimeter).
While
As illustrated in
End bracket(s) 156 and/or end reflector(s) 158 may cooperatively fix the junction box end cap(s) 150 to the driver bracket 148. The end reflector(s) may have a reflective surface arranged to reflect the light emitted by the plurality of LEDs 126(A) and 126(B).
In addition to the thin height 204 of the low profile LED fixture 102, because the flange(s) 110(A) and 110(B) may extend in towards the middle 112 of the housing 104 at the acute angle 114, the flange(s) 110(A) and 110(B) may prevent foreign objects from grabbing, hooking, gripping, etc., the flange(s) 110(A) and 110(B). For example, the acute angle 114 may keep a hand from making static friction between the hand and the flange(s) 110(A) and 110(B). Thus, the hand slips or displaces along the flange(s) 110(A) and 110(B) with a kinetic friction, preventing the hand from gripping the flange(s) 110(A) and 110(B) or causing damage to the LED fixture 102. Similarly, the acute angle 114 may reduce a force applied from an impact of an object (e.g., an antenna of a vehicle). For example, the acute angle 114 may deflect a blunt or direct impact against the flange(s) 110(A) and 110(B), reducing the force applied from the impact of the object on the flange(s) 110(A) and 110(B).
In one example, detail view 208 depicts that the lens 140 may include ribs 210. The ribs 210 may be arranged substantially perpendicular to the opposing first and second flange(s) 110(A) and 110(B). The ribs 210 may provide for spreading or diffusing the light emitted from the plurality of LEDs 126(A) and 126(B). For example, the ribs 210 may spread or diffuse LED bright spots.
The flange(s) 110(A) and 110(B) may dissipate the heat to the base 116. Because the plurality of LEDs 126(A) and 126(B) are thermally fixed to the opposing flange(s) 110(A) and 110(B), the heat transfer performance of the housing is significantly increased. For example, the flange(s) 110(A) and 110(B) provide two distinct heatsinks that allow for air flow across each of the flange(s) 110(A) and 110(B), as well as natural convection and conduction up towards the base 116.
This is compared to thermally fixing the plurality of LEDs 126(A) and 126(B) in a single row down the middle 112 of the housing 104. In this example, the plurality of LEDs 126(A) and 126(B) may be densely populated along the middle 112 of the base 116. Because the plurality of LEDs 126(A) and 126(B) may be densely populated along the middle 112 of the base 116, the plurality of LEDs 126(A) and 126(B) are only able to dissipate heat to a smaller thermal interface area, as compared to the example embodiment where the plurality of LEDs 126(A) and 126(B) are thermally fixed to the opposing flange(s) 110(A) and 110(B). Further, because the base 116 may be mounted adjacent to the ceiling 202, the base 116 may provide a heatsink with little to no airflow, and poor natural convection. This is because the interface between the base 116 and the ceiling 202 may provide little to no airflow, and the base 116 may be arranged horizontal to ceiling 202. However, in some embodiments, at least some of the LEDs may be disposed on or around the base 116 (e.g., to achieve a greater spacing between the LEDs in the housing 104).
The plurality of LEDs 126(A) and 126(B) may be arranged to emit light 306 towards the middle 112 of the housing 104 opposite the aperture 124 of the housing 104. For example, the plurality of LEDs 126(A) and 126(B) may emit light 306 substantially perpendicular to the flange(s) 110(A) and 110(B), and at an acute angle to the base 116 of the housing 104. In one embodiment, the acute angle 114 may be about 45 degrees, and the plurality of LEDs 126(A) and 126(B) emit light 306 substantially perpendicular to the flange(s) 110(A) and 110(B), and at an acute angle of about 45 degrees to the base 116 of the housing 104. In another example, the acute angle 114 may be about 35 degrees, and the plurality of LEDs 126(A) and 126(B) emit light 306 substantially perpendicular to the flange(s) 110(A) and 110(B), and at an acute angle of about 55 degrees to the base 116 of the housing 104. The acute angle 114 may be any acute angle suitable to aim the plurality of LEDs 126(A) and 126(B) generally towards the middle 112 of the housing 104.
The reflector(s) 136(A) and 136(B) may reflect the light 306 emitted by the plurality of LEDs 126(A) and 126(B). The reflector(s) 136(A) and 136(B) may have a reflective surface 138 to reflect the light 306 emitted by the plurality of LEDs 126(A) and 126(B) out of the aperture 124, and through the lens 140. The reflector(s) 136(A) and 136(B) may be fixed to the cable management bracket 148 at an end 310(A) of the reflector(s) 136(A) and 136(B), and interfere with a portion of the plurality of LEDs 126(A) and 126(B) at another end 310(B) opposite the end 310(A). The reflector(s) 136(A) and 136(B) may have a substantially curvilinear cross-sectional area 308 arranged between the ends 310(A) and 310(B). The substantially curvilinear cross-sectional area 308 may be substantially concave shaped, ear-shaped, crescent shaped, half-circle shaped, or the like. Further, the reflector(s) 136(A) and 136(B) may have a substantially rectilinear cross-sectional area arranged between the ends 310(A) and 310(B). Further, the reflector(s) 136(A) and 136(B) may be include a cross-sectional area having a shape that is specific to a particular application the LED fixture 102 may be used for. For example, the shape of the reflector(s) 136(A) and 136(B) may be customized based on a desired light pattern.
Detail view 314 illustrates that the plurality of LEDs 126(A) and 126(B) may have a thickness 316 ranging from about 0.2 inches (5 millimeters) to about 0.6 inches (15 millimeters). The thin thickness 316 of the plurality of LEDs 126(A) and 126(B) provides for the plurality of LEDs 126(A) and 126(B) to be comfortably fixed on the inside wall 302 of the acutely angled flange(s) 110(A) and 110(B) and maintain the thin profile of the LED fixture 102. For example, because the plurality of LEDs 126(A) and 126(B) may be comfortably fixed on the inside wall 302 of the acutely angled flange(s) 110(A) and 110(B), the LED fixture 102 maintains the overall thin height 204.
Similar to the lens 140 discussed above, the rectilinear lens 404 may be arranged to be fixed to edge(s) 406(A) and 406(B) of the flange(s) 110(A) and 110(B). For example, the rectilinear lens 404 may include edge(s) 408(A) and 408(B) configured to cooperate with the edge(s) 406(A) and 406(B) to fix the rectilinear lens 404 to the housing 104. The rectilinear lens 404 may include the ribs 210 arranged substantially perpendicular to the opposing first and second flange(s) 110(A) and 110(B).
Although embodiments have been described in language specific to structural features and/or methodological acts, it is to be understood that the disclosure is not necessarily limited to the specific features or acts described. Rather, the specific features and acts are disclosed as illustrative forms of implementing the embodiments. For example, in various embodiments, any of the structural features and/or methodological acts described herein may be rearranged, modified, or omitted entirely. For example, the shape, size, and configuration of the LED fixtures may be varied.
