Luminaire with long chains of lower power LEDs and multiple on-board LED drivers

A luminaire may include an input connection that receives AC line voltage, one or more chains of LEDs, and one or more drivers for driving each chain of LEDs, all within a housing, which may be in the form of a canopy. Each chain of LEDs may contain at least 36 LEDs connected in series. Each LED may have a power rating of no more than 1 watt and may be oriented to direct light outside of the housing when illuminated. Each driver may receive power that is extracted from AC line voltage connected to the input connection and provide one or more outputs that drive at least one of the chains of LEDs.

BACKGROUND

1. Technical Field

This disclosure relates to luminaires, including outdoor lighting canopies that are driven by AC line voltage and include multiple LEDs.

2. Description of Related Art

Outdoor canopy lighting may utilize multiple LEDs mounted within a housing to provide needed lighting. These LEDs may need a driver to generate the regulated current that is needed to drive the LEDs.

A single large driver is usually mounted outside of the luminaire housing to drive the LEDs. This has been done because of concern over the effect of noise generated by the LEDs within the housing on the operation of the driver, because of the absence of strong surge protection inside of the luminaire housing to protect the driver from surges in line voltage, and to make it easy to replace components in the driver that sometimes fail, such as electrolytic capacitors. However, positioning the driver outside of the canopy housing may require a separate housing to house the driver. This may add to costs and require added space for the separate housing

Drivers have also been designed to drive a chain of series-connected LEDs in sub-chain steps that correspond to the amplitude of the line voltage. Typically, the chain and each of its sub-steps consist of a small number of high power LEDs to minimize costs and maximize durability. However, high power LEDs can be less efficient and using a small number can result in spotted lighting patterns.

SUMMARY

A luminaire may include an input connection that receives AC line voltage, one or more chains of LEDs, and one or more drivers for driving each chain of LEDs, all within a housing. Each chain of LEDs may contain at least 36 LEDs connected in series. Each LED may have a power rating of no more than 1 watt and may be oriented to direct light outside of the housing when illuminated. Each driver may receive power that is extracted from AC line voltage connected to the input connection and provide one or more outputs that drive at least one of the chains of LEDs.

Each chain of LEDs may include multiple sub-chains of LEDs connected in series, each sub-chain containing multiple LEDs in series. Each of the LED drivers may provide a separate output that drives at least one of the chains of LEDs at each of the junctions between each of its sub-chains in a stepped sequence that is a function of the level of voltage of the power that is received by LED driver.

At least one sub-chain within each chain may include at least 12 LEDs.

No sub-chain within each chain may include less than 6 LEDs.

The outputs of at least two of the LED drivers may be connected in parallel.

The outputs of at least one of the LED drivers may be connected to one of the chains of LEDs and the outputs of at least one other of the LED drivers may be connected to another of the chains of LEDs.

The input connection, the chains of LEDs, and the LED drivers may all be on a single printed circuit board.

Each chain of LEDs may have at least 48 LEDs.

The power rating of each LED may be no more than 0.6 watts.

The housing may form a canopy light.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Illustrative embodiments are now described. Other embodiments may be used in addition or instead. Details that may be apparent or unnecessary may be omitted to save space or for a more effective presentation. Some embodiments may be practiced with additional components or steps and/or without all of the components or steps that are described.

While the preferred embodiment uses light emitting diodes (“LEDs”) as light sources, other light sources may be used in addition to LEDs or instead of LEDs within the scope of the present disclosure. By way of example only, other light sources such as plasma light sources may be used. Further, the term “LEDs” is intended to refer to all types of light emitting diodes including organic light emitting diodes or “OLEDs”.

While the luminaire depicted in the Figs. is generally applicable to any application that would benefit from indoor or outdoor area lighting, it is well-suited, in one example, for application to canopies and the like such as those used at petroleum refill stations. In other applications, luminaires and mounting structures disclosed herein are applicable to soffits or ceilings.

FIGS. 1A and 1Bdepict bottom-side and top-side perspective views of a luminaire100, in accordance with the present disclosure, which is a low-profile luminaire capable of providing proper light distribution and having a minimum number of parts. The luminaire100comprises a housing102, a circuit board104populated with light sources106such as LEDs, a plurality of screws108, a lens110, a gasket112and a lens frame114. The circuit board104can be any known circuit board for properly arranging the light sources106and, in one embodiment, can be a printed circuit board (“PCB”). For the sake of simplicity, circuit board104will be referred to herein as a PCB, but it will be understood that any type of circuit board is suffice.

The overall shape of the luminaire100is depicted as substantially square with rounded corners, but other shapes are contemplated as operating within the scope of this disclosure. By way of example only, rectangular, circular and triangular are all contemplated. Because the overall shape of the luminaire100is dictated in the depicted embodiment by the shape of the housing102and the lens frame114, the shape of the housing102and lens frame114are likewise contemplated as have these exemplary shapes or others.

The housing102comprises a plate116, a perimeter118and a wall120between the face116and the perimeter118. The perimeter118extends about the perimeter of the housing and thus takes the shape of the housing, which in the depicted embodiment, is square with rounded corners, as discussed above. The perimeter118defines a front face118aand a rear face118b. The front face118aof the perimeter118extends from an inner edge118cto an outer edge118dwhich defines the outermost perimeter of the housing102. The perimeter inner edge118cdefines the downward most facing portion of the housing102. The front face118aof the perimeter118extends from the perimeter inner edge118cto the perimeter outer edge118dforming a curvilinear front face118a. In the depicted embodiment, the curvilinear front face118ainitially extends outward form the inner edge118cin straight horizontal manner, and then curves upward with an ever-increasing radius of curvature to the perimeter outer edge118d. Other curvilinear shapes are contemplated as falling within this disclosure. By way of example only, the front face could extend horizontally to a 90° edge, which then extends upward to the outer edge.

References herein to upward and downward orientation are with reference to the depicted embodiments in which the luminaire100is mounted to the underside of a flat structure (such as a ceiling or a canopy) and are for purposes of conveying a description of the elements of the disclosure, but are in no way intended to be limiting. In application, upward can be reoriented downward and downward can be reoriented upward.

The housing perimeter118preferably defines one or more locator grooves122extending from the perimeter front face upward into the perimeter with a locator groove wall122ato a locator groove base122bthat is flat in the depicted embodiments, but can vary, extending horizontally. The locators grooves122receive locator bosses140on the lens frame114to assist in properly locating the lens frame114on the housing102and, separately, to accommodate a boss from the lens frame114which can receive a mounting screw134from the groove base122b, which will remain hidden from sight to persons viewing the bottom of the luminaire100, in the depicted embodiment.FIG. 4Bdepicts a cross-section of a portion of the luminaire100through a locator groove122, a corresponding locator boss140and mounting screw134.

In the depicted embodiment, the luminaire100defines two locator grooves122on each of the four sides defining the square shape of the luminaire100. Greater or fewer locator grooves122are contemplated. For example, if the locator grooves122are used purely for locating the lens frame114on the housing102, then one, or two would suffice. Alternatively, an embodiment of the luminaire100is contemplated with no locator grooves122. If, however, the locator grooves122are used to accommodate a boss to facilitate mounting the housing102to the lens frame114by screw, or the like, then the number and location of the locator grooves112will be dictated by the size and weight of the lens frame114in order to properly secure the lens frame114to the housing102with sufficient sealing there between, if desired, as discussed below.

The housing plate116extends across the housing to fill in the area surrounded by the housing perimeter118. The housing wall120extends downward from the housing plate116just inward of the housing perimeter118to a distal end120aand about the entire housing plate116as depicted inFIG. 2A. The housing wall120does not extend as far down as the inner edge of the perimeter118. Rather, the housing wall120extends downward far enough to engage the gasket112located in the lens frame114as shown inFIGS. 4A-4Dand discussed below. In this manner, the wall120deforms the gasket112forming a vapor and moisture barrier there between. Because the wall120and gasket112extend about the entire luminaire100just inward of the perimeter118, a vapor and moisture barrier is formed between areas inward of the wall120(e.g. the PCB) and areas outward of the wall120. This construction forms a barrier against vapor and moisture that might otherwise ingress between the housing102and lens frame114. The housing wall120can take different forms as seen inFIGS. 4A-4Din order to minimize weight and material while still creating sufficient deformation of the gasket112to create desired vapor and moisture barrier.

The housing plate116has a front face116aand a rear face116b. The housing plate front face116ais substantially flat, extending across and filling in the perimeter118, with the exception of a plurality of mounting holes124defined therein and a spacer boss126surrounding and extending each mounting hole124out beyond the housing plate front face116a. Each spacer boss126comprises a cylindrical wall extending downward from the housing plate front face116ato a distal end126aand configured so that an inner wall of the spacer boss126continues the inner wall of the corresponding mounting hole124so that the spacer boss126effectively extends the depth of the mounting hole124to a depth B. In the depicted embodiment, the spacer boss distal end126asits approximately even with a front face104aof the PCB (as depicted inFIGS. 4A and 4D), thus acting to space the head of the screws108a distance approximately equal to the thickness of the PCB, shown as distance C inFIG. 4D, to the PCB front face104a. In one exemplary embodiment, distance B can be 0.125 inches, where the distance C can be 0.047 inches. In another exemplary embodiment, height of the spacer bosses126is just short of the thickness of the PCB104so that the screws108not only hold the PCB104from falling off the housing102, but also hold it steady, preventing rattle of the PCB104and creating a heat transfer connection between the PCB104and the housing102causing the housing102to act as a heat sink for the PCB104and the LEDs106mounted thereon. These objectives are enhanced when the screws108are constructed of a pliable material, as discussed below. The height of the spacer bosses126could be 0.002 inches shorter than the thickness of the PCB104in one embodiment. Other dimensions are contemplated to meet these objectives.

In an alternative embodiment, no spacer bosses126are employed. However, the spacer bosses126provide two advantages. First, the spacer bosses126reduce assembly time by allowing screws108to be driven into the mounting holes124without regard for when they reach the PCB104. Without the spacer bosses126, advancing the screws108would be conducted with concern about advancing them too far or with too much power, either of which might damage the PCB104. The spacer bosses126obviate that concern by allowing the screws108to be advanced to the spacer boss distal end126aas quickly and efficiently as possible. This ease of securing the screws108to the housing102without damaging the PCB108is further advanced by using screws108of a pliable material such as, by way of example only, nylon. Use of such pliable screws108will allow the screws108to be advanced without regard for exactly when advancement need stop. That is, over advancing the screws108will not “strip” the mounting holes124or damage the screws108to an extent such to prevent them from holding the PCB104to the housing102. Instead, by using screws108of a pliable material, over advancing the screws will slightly deform the threads of the screws108, but not so much as to prevent the pliable threads of the screws108from grasping the inside of the mounting holes124.

Moreover, in the depicted embodiment, the inner wall of the mounting holes124is straight (i.e. is not threaded). This further limits production costs by removing the need to tap the mounting holes124or create a complicated mold having reliable threads in the mounting hole124. Additionally, using straight mounting holes124actually allows shallower mounting holes124because the use of a typically tap to create the threads in a mounting hole requires a certain depth in order to facilitate the tapping. Using straight holes eliminates the need to be able to tap the mounting holes124, thus allowing shorter mounting holes124than could otherwise be used. In one exemplary embodiment, the depth B of the mounting holes124is 0.125 inches. Furthermore, by using the spacer bosses126to extend the wall of the mounting hole124out to the face of the PCB104, the depth of the mounting hole124is moved into the luminaire100, reducing the distance that the mounting hole124need extend toward the housing plate rear face116b, thus allowing a thinner overall luminaire100. Moreover, using pliable screws108in straight mounting holes124further reduces, or eliminates, the likelihood of damaging the screws108by over advancement.

The second advantage provided by the spacer bosses126is their inherent ability to reduce tolerances in the stack of elements (housing102, PCB104, screws108, lens110and lens frame114) contributing to the over all height of the luminaire100, and thus its low-profile. As discussed in greater detail below, tight stack of these element contributes to the low-profile. The ability to advance the screws108against the spacer bosses126without exception so as to limit the tolerances necessary and contribute to an overall low profile. The additional cost of these spacer bosses is negligible in an embodiment where the housing is cast from a material (e.g. aluminum).

The housing plate rear face116bis also substantially flat, with the exception of a matrix of interconnecting walls128extending from the rear face116ba short distance off that face. This matrix128increases the overall rigidity of the plate116and thus the housing102. The matrix128also provides additional surface area on the rear of the housing102to increase the ability of the housing to dissipate heat when any of the matrix128is exposed to ambient air. The matrix128also assists in providing surface contact with structure to which the housing is mounted when that structure has surface irregularities (i.e. is not flat). This surface contact can also be helpful in directing heat away from the luminaire100in installations such as a petroleum refill station canopy which is constructed of sheet metal and much of the sheet metal, except where contacted by the housing, is exposed to ambient air to facilitate transferring to the surrounding air, some of the heat generated by the light sources or utilities for powering the light sources.

The matrix128may optionally include bosses130at the bottom of the mounting holes124. These bosses130provide additional thickness to account for molding irregularities.

In the depicted embodiment, the housing perimeter rear face118bfollows the curvature of the housing perimeter front face118afor the most part. A cross-section of one embodiment is depicted inFIG. 4C. This embodiment keeps the perimeter thin and reduces material usage while the curvature provides structural rigidity. Other shapes and thicknesses are contemplated. The housing perimeter rear face118balso includes the backside of the locator groove wall122aand locator groove base122bprotruding therefrom.

As discussed above, one or more of the locator groove bases122bdefine a screw aperture132to accommodate a screw134to extend through the housing102and into the lens frame114to secure the lens frame114to the housing102. In the depicted embodiment, the screw134enters from the housing and extends into the lens frame114so as to not be visible from the front side of the luminaire100. A cross-section of this embodiment is depicted inFIG. 4B. Other embodiments are contemplated.

In order to minimize the number of screws134necessary for assembly and minimize the corresponding assembly steps, one or more fins136may extend across the housing perimeter rear face118bto fill in the back side of the housing perimeter118curvature and provide the housing perimeter188with added structural rigidity. In the depicted embodiment, each side of the square housing comprises a single such fin136between the two screws134and one such fin136at each rounded corner of the housing perimeter118. A cross-section of this embodiment is depicted inFIG. 4A. Other embodiments are contemplated.

The lens frame114defines a front face114aand a rear face114band comprises a lens frame perimeter136at the outermost perimeter of the lens frame136and a trough138defined by an inner trough wall138aand outer trough wall138b. The contour of rear face114bof the lens frame perimeter136follows the contour of the housing perimeter front face118a, extending to a distal end136athat lies in approximately the same horizontal plane as the housing perimeter outer edge118d. References herein to a “horizontal” plane are by way of describing relationships between elements and portions of elements in the disclosed luminaire100and the term “horizontal” is used because the luminaire100is described as being mounted to a ceiling or the like. Use of the term “horizontal” is not limiting on the luminaire100as it could be rotated to be mounted in any orientation. By extending the lens frame perimeter distal edge136ato the housing perimeter outer edge118d, the lens frame can cover the housing perimeter118from view to provide the luminaire100a simple and elegant aesthetic look as seen inFIG. 1A. One of more locator boss140extends rearward from the lens frame rear face114binto the curvature defined by the lens frame perimeter136. As described above, the locators grooves122of the housing102receive the locator bosses140to assist in properly locating the lens frame114on the housing102and, separately, to receive the mounting screw134, which will remain hidden from sight to persons viewing the bottom of the luminaire100, in the depicted embodiment.FIG. 4Bdepicts a cross-section of a portion of the luminaire100through a locator groove122, a corresponding locator boss140and mounting screw134. The lens frame114is oriented vertically at the distal edge136and then curves downward and inward with an ever increasing radius of curvature the farther it is from the distal edge136until it is oriented approximately horizontal where it is adjacent to the housing perimeter inner edge118c.

A base138cof the lens frame trough138continues to extend inward from the lens frame perimeter136horizontally and seamlessly from the lens frame perimeter136. Other embodiments are contemplated. The lens frame trough inner trough wall138athen extends vertically to define the lens frame innermost perimeter which defines a lens frame aperture142through which light emitted by the light sources106passes to leave the luminaire100.

Gasket112is located about the perimeter of the trough outer wall138b(depicted inFIG. 3BandFIGS. 4A-4D, but notFIG. 3A), which holds the gasket112in place during assembly. When the housing102and lens frame114are brought into alignment with, and secured one to the other, the housing wall120contacts and deforms the gasket112. In the deformed state, the gasket112forms a seal against ingress of vapor, moisture, water or dirt between the housing102and the lens frame114. The gasket112extends around the entire perimeter of the outer trough wall138band the housing wall120extends around the entire housing102such that the seal formed between the housing wall120and the gasket112extends about the entire perimeter of the PCB104preventing ingress of vapor, moisture, water or dirt between the housing102and the lens frame114that could reach the PCB104or other portions of the luminaire100within that perimeter seal. In an alternative embodiment, a urethane sealant could be substituted for the gasket112. For the sake of efficiency, this urethane adhesive could be the same urethane adhesive as used in the trough138, as discussed below.

The trough inner wall138aextends upward a distance A (FIG. 4D) from the trough base138cto a distal end on which the lens110rests. The lens110is sized so as to rest on the trough inner wall138adistal end and extend almost all of the way to the trough outer wall138b, leaving at least sufficient space there between to ease assembly. The trough outer wall138bextends upward from adjacent the lens frame perimeter136and upward beyond the lens110. The trough inner wall138ais therefore shorter than the trough outer wall138b. An adhesive sealant144is deposited into the trough138during assembly in a bead having a height sufficient so that when the lens110is placed on top of the bead, the lens110will deform the bead of adhesive sealant144until the lens110contacts and rests on the tough inner wall138adistal end. The height of the trough inner wall138ais a height A, and is designed to prevent the lens110from squeezing all of the adhesive sealant144out from between the lens frame114and lens110by limiting the distance between the lens110and the trough base138cto height A. In this manner, the deformed bead of adhesive sealant144will have sufficient height to provide adhesion between the lens110to the lens frame114. In one exemplary embodiment, the height A is 0.094 inches when using a 0.225 inch diameter bead of a urethane adhesive (SikaTack®-Ultrafast, sold by Sika Corporation, in one embodiment). In this embodiment, it has been found that the bead compresses to approximately the height A and approximately 0.425 inches, providing sufficient surface area to adhere to the lens110. Other heights A, bead diameters and adhesive sealants are contemplated.

As depicted inFIGS. 4A-4D, the lens110in the assembled luminaire100, is held by inner trough wall138aand forced into contact with the head of the screws108. In this depicted embodiment of the luminaire100, the head of one or more of the screws108is sized (height of D) to facilitate this contact between the heads of the screws108and the lens110. This contact holds the screws108in the mounting holes124and eliminates the need for any holding force between the screws108and the mounting holes124once the luminaire100is assembled. The need for only short term holding force between the screws108and mounting holes124can further reduce the requirements of the mounting hole124and the screws108allowing them to be even shorter and allowing an even thinner overall luminaire. The short term requirement for this holding force can also reduce the requirements of screws108, reducing the overall cost of the luminaire100. In one exemplary embodiment, the height of the screws is just sufficient to prevent the screws108from backing off the force with which they press on the PCB104. In an alternative exemplary embodiment, the lens110increases the force with which the screws108press on the PCB104. In one exemplary embodiment, the height D of the head of such screws108is 0.190 inches. Alternative embodiments are also contemplated in which the screw108is not held by the lens110or are rivets through the PCB104and through a hole (not depicted) in the housing102. Other attachment hardware is also contemplated.

The PCB104comprises a PCB front face104apopulated with LEDs106and a PCB rear face104b. The PCB rear face104bis pressed into contact with the housing102by the screw108to create sufficient contact between the PCB104and the housing102to allow the housing102to act as a heat sink, taking away heat generated by the LEDs106and associated circuitry.

With the exception of the LEDs106, the PCB front face104ais covered with a reflective coating or covering. In one exemplary embodiment, the PCB front face104ais covered with a white adhesive paper adhered to the PCB front face104a. In another embodiment, the PCB front face104ais covered with a sheet of reflective aluminum (not depicted). The reflective coating or covering covers the PCB from view while, at the same time, redirecting light off of the PCB front face104arather than absorbing it. Many luminaires, especially those using LEDs, place reflectors or optics near the light sources to redirect light emitted from the light sources to travel out of the luminaire. When using this reflective coating or covering discussed above, the luminaire of the present disclosure does not use any such reflectors or optics. The absence of reflectors and optics allows the distance between the PCB104and the lens110to be set as low as desired, bounded only by the need to secure the PCB104to the housing102. In this manner, the absence of any reflectors or optics further contributes to a thin (i.e. low-profile) luminaire100.

In order to further reduce the overall height of the luminaire100, the light sources are LEDs106comprised of 0.25 Watt LEDs rather than larger, more powerful LEDs. Historically, one challenge of using LEDs for area lighting has been that LEDs have traditionally emitted insufficient light to replace more conventional light sources such as incandescent or fluorescent. This deficiency has traditionally been overcome by the use of a matrix of LEDs. However, as the acceptance of LEDs for area lighting has become more accepted, technologies have been driven to increase the lumen output LEDs. As the technologies have advanced in this manner, conventional thinking in the LED lighting industry has been to use the biggest and brightest LEDs available for area lighting. The luminaire100of the present disclosure takes advantage of the advances in technology, but bucks traditional thinking by using a larger number of smaller, low output LEDs106as opposed to a larger number of larger, higher lumen output LEDs. The use of these smaller, low-output LEDs106provides the luminaire100two advantages.

First, many manufacturers currently manufacture and sell 1 Watt LEDs. For example, Nichia sells the NS9W383 1 Watt LED. This 1 Watt LED has a height of approximately 0.108 inches. Instead of using these, or other, 1 Watt LEDs, the LEDs106used by the luminaire100are 0.25 Watt LEDs. In one exemplary embodiment the LEDs106are Nichia NS2W757A LEDs. More LEDs106are required to provide the luminaire100the same lumen output than would be necessary if the 1 Watt LEDs were used. However, the 0.25 Watt LEDs106reduce the height of the LEDs by 0.086 inches, allowing further reduction in the overall height of the luminaire100.

In one embodiment of the disclosed luminaire depicted inFIG. 6, the PCB104is populated with 460 Nichia 0.25 Watt NS2W757A LEDs arranged in a matrix spacing them at a pitch of 0.625 inches. When driven at 530 mA, these 460 LEDs emit approximately 37 lumens each for a total of approximately 17,000 lumens. When driven at 650 mA, these 460 LEDs emit approximately 44 lumens each for a total of approximately 20,240 lumens.

Second, it has been found that the larger number of lower Watt and lumen LEDs106provide a more even light distribution that is more pleasant to the eye. This more even glow can be expressed as a ratio of the lumens (L) per LED106to the pitch (P) of the LEDs106. In the embodiments disclosed in the preceding paragraph, each of the 460 LEDs are spaced at a pitch P of 0.625 inches. When these LEDs are driven at 530 mA they produce approximately 37 lumens each for a ratio of 59.2 lumens/inch. When these same LEDs are driven at 650 mA they produce approximately 44 lumens each for a ratio of 70.4 lumens/inch. Other lumen outputs per chip and pitches are acceptable. It has been found that a P/L ratio of between approximately 59.2 lumens/inch and approximately 70.4 lumens/inch provide a combined even glow when the 0.25 Watt LEDs are illuminated. This ratio is contemplated as applicable to LEDs of other small wattage.

The accumulation of the above discussed advantages of the disclosed luminaire100result in an overall thin (i.e. low profile) luminaire100. With the height E between the rear of the housing102and the housing plate front face116a(0.193 inches in one exemplary embodiment) minimized to the thickness of a plate necessary for molding the mounting holes124in the housing plate front face116aand the matrix128on the housing place rear face116b, the height E can be less than 0.2 inches and it has been found that a height of 0.193 inches is optimal. Furthermore, use of pliable screws108, with straight mounting holes124, spacer bosses126, thin LEDs106and a lens frame trough138having an inner trough wall138aworking in conjunction with the screws108to precisely control the height of the lens110with respect to the PCB104and the lowermost extremity of the lens frame aperture142creates a high precision, low tolerance stack of parts that facilitate a precisely thin luminaire100that eliminates the need for reflectors or optics thus further reducing the thickness of the luminaire100. The height F between the housing plate front face116aand the lowermost extremity of the lens frame aperture142(0.510 inches in one embodiment) is thus minimized and in conjunction with the minimized height E, provides an overall low profile, highly efficient luminaire100. In the exemplary embodiment of height E being 0.193 inches and height F being 0.510 inches, the total height of the luminaire is only approximately 0.703 inches and is facilitated by one or more of the above discussed features.

The low height F, minus the low height C of the PCB104provides a very low height between the base of the LEDs106and the lowermost extremity of the lens frame aperture142through which light rays emitted from the LEDs106escape the luminaire100. This resulting low height allows most of the lumens emitted from the LEDs106to escape the luminaire100without need for reflectors or optics. In the example identified above using 460 Nichia 0.25 Watt NS2W757A LEDs driven at 650 mA to emit a total of 20,240 lumens, it has been found that of the 20,240 emitted lumens, 20,195 escaped the luminaire100in this configuration.

In one embodiment of the disclosed luminaire, a driver column146extends upward from the rear of the housing plate116. The driver column146may be integral with the housing plate146or not integral. In the depicted embodiment, the driver column146is integrally cast as part of housing102. The driver column146comprises four wings148extending radially from a central axis of the driver column146. The driver column148could comprise greater or fewer wings148; three in one exemplary embodiment. Each wing148extends upward from the housing plate116, having opposing lateral walls148aand a circumferential wall148bat the circumferential perimeter of the driver column146. In the exemplary depicted embodiment, the circumferential wall148bextends approximately tangential to the circumference of the driver column146and the opposing lateral walls148aextend approximately perpendicular to the circumferential wall148binward generally toward the central axis of the driver column146. The entire driver column146, including the wings148, are depicted as hollow, which is a result of the cost savings available by producing the housing102, including the driver column146as an integral, unitary casting. Other embodiments are contemplated, however. For example, the wings could be solid and/or secured to the housing in an alternative embodiment.

Each wing148defines a mounting boss150at its top152for receiving fixing hardware for mounting a driver box200to be associated with the luminaire100during installation. In the depicted embodiment, the mounting boss defines a screw hole154for receiving a screw, but other fixing hardware is contemplated in the alternative. The mounting boss152is limited to the outer portion of each wing148, leaving a recessed land156defined by the four mounting bosses152.

An aperture158is defined at the center of the driver column146through the land156to allow utilities to pass from the luminaire100to the driver box200. For example, wiring160to provide power to the light sources passes through the aperture158to deliver power from a driver located in the driver box200to the light sources.

In an exemplary embodiment, the aperture158is designed to allow air to pass therethrough, even when the wires160are present. Air expands and contracts as it is heated and cooled, respectively. As discussed above, the seal created by gasket112seals the air in the portions of the luminaire100inward of the gasket from the ambient environment. Thus sealed, the expansion and contraction of this sealed air would create air pressure above or below the ambient air pressure unless that sealed air was somehow vented. If the air pressure of this sealed air were to fall below the ambient air pressure, then the luminaire100would tend to try to draw air outside the luminaire, along with any dirt, moisture, etc. into the luminaire. Over time, this could tend to break down the seal created by the gasket112. Allowing air to pass through the driver column aperture158allows the luminaire100to breath and prevents the luminaire100from trying to draw moisture across the seal created by the gasket112.

In one particular exemplary embodiment of the luminaire100, a breathing tube162is run through the aperture158along with the wiring160and a sealant164fills the remainder of the aperture158so that no moisture, air, dirt, etc. can pass through the aperture unless through the breathing tube162. In one embodiment, the sealant164is the same urethane adhesive discussed above. In another embodiment, the sealant164is an elastomer. Other sealants164are contemplated. In yet another exemplary embodiment, a cylindrical gland166having a sealant164therein is screwed into threads formed in the aperture158and the breathing tube162and wiring160are run through the sealant164, which forms a tight seal around the breathing tube162and wiring160to prevent ingress of any dirt, moisture, air, etc. into the luminaire100. The gland166could be a commercially available liquid tight fitting for individual conductors such as a Conta-Clip brand model PG9, in one example. Other embodiments are contemplated. Regardless of how the sealant164is provided, the breathing tube162is run into the driver box200to prevent rain water, dirt, etc. from entering the breathing tube162and running down into the luminaire100.

The driver box200comprises a box having a bottom wall200aand perimeter walls200bcreating an upwardly open box. The driver box200is closed by a cover plate202having a central plate202aand downwardly depending edges202balong each side of the central plate202ato direct water, snow, etc. downward past the opening to the driver box200. In one exemplary embodiment, the central plate202aextends outward beyond each wall200bof the driver box to further prevent water, snow, etc. from entering the driver box. The driver box comprises mounting hardware to facilitate securing the cover plate202to the driver box200. In one embodiment, the driver box200comprises driver box ears200cextending from one or more driver box walls200aand defining a hole therein to receive a screw for securing the cover plate202to the driver box200. In the depicted embodiment, driver box ears200cextend from two opposing ones of the driver box walls200a. By extending the driver box ears200c, and thus the hole in the cover plate202to accommodate the screws, outward beyond the driver box walls200a, any rain, snow, etc. falling through the hole in the driver box cover plate202will fall outside of the driver box200rather than into the driver box200. In one possible embodiment, the driver box ears200cdo not extend as high as the driver box walls200a, but fall just short thereof. This prevents any water that may fall through the screw holes in cover plate202from traveling across the driver box ears200cand into the driver box. Alternatively, the driver box ears200cmay extend as high as the driver box walls200a, but have a groove extending across the driver box ears200cbetween the screw holes and the driver box wall200a.

A stem204extends downward from the driver box bottom wall202a. In the exemplary depicted embodiment, the stem204is integrally cast with the driver box200, but other options are contemplated. The stem204is configured to slide over the driver column146of the luminaire and accommodate the driver column146within the stem204. In one embodiment, the stem comprises a wall204ahaving an inner surface defining an opening204bto receive the driver column146. A top204cof the opening204bmay be defined by the driver box bottom wall202a(as in the depicted embodiment) or by a separate top204c. The opening top204ccan be shaped to complement all or portions of the top of the driver column146so that the driver box200will sit securely on the driver column146. The stem opening top204cdefines a utilities aperture204dto accommodate the wiring160and the breathing tube162and gland166, where present, allowing them to enter the driver box200. The breathing tube162need only enter the driver box200and be protected from the elements by the driver box200and cover plate202. The wiring160enters the driver box200through the utilities aperture204dand is connected to a driver (not depicted) for providing power to the light sources. One or more hardware apertures204eare defined in the top204cand configured to allow screws or the like to pass through and secure into a corresponding one of the screw holes154on the driver column146to secure the driver box200to the driver column146and, thus, the luminaire100.

In one embodiment, the stem wall204adefines a lower edge204fand a groove206about the entirety of the lower edge204f. The groove206accommodates a gasket208. In the depicted embodiment, the stem wall204ais cylindrical and the groove208and corresponding gasket208are circular. Other embodiments are contemplated.

During installation to a structure210, the housing102is elevated to the structure and the driver column146passed through an aperture210ain the structure. The structure210could be, by way of example only, a ceiling or a canopy for a petroleum refill station. The structure aperture210acould be a pre-existing aperture left over from a previously installed luminaire or it could be a newly constructed aperture. The gasket208rests in the groove206defined by the stem wall lower edge204fand becomes compressed when brought into contact with the structure and the stem204tightly secured to the driver column146. When in this compressed state, the gasket208forms a seal around the structure aperture210ato prevent material above the structure (e.g. dirt, water, etc.) from getting to the structure aperture210a. The ability of the gasket208to prevent material from getting to the structure aperture210ain this manner is predicated on the gasket208and the groove206, in which is resides, being larger than the structure aperture210a. In one exemplary embodiment, the stem wall204ais sized to allow the gasket208to circumscribe at least a 4 inch diameter structure aperture210a, which is commonly left behind by pre-existing luminaires. Other dimensions are also contemplated. While this size stem is larger than necessary for some applications, it has also been found that the large size of the stem also assists in providing stability of the structure210when the structure is somewhat flexible, such as in a sheet metal canopy as is often found at a petroleum refill station.

The stem204is preferably of a height to elevate the driver box200, or portions thereof, above the height where water, snow, etc. may be allowed to accumulate. For example, a sheet metal canopy a petroleum refill station will often accumulate some water and/or snow during precipitation before that water is directed off the canopy. The height of the stem is preferably designed so that the driver box200is above the height to which water and/or snow are likely to accumulate. In this embodiment, the driver within the driver box200is more likely to be kept dry than if the stem places the driver box200below that height.

A mounting apparatus300is depicted inFIGS. 7A-7Gwhich can be used with the luminaire100described above, or with a different luminaire. For continuity, the mounting apparatus300of the present disclosure will be described in conjunction with the luminaire100previously described herein. The mounting apparatus300is beneficial in mounting a luminaire, such as luminaire100, to a mounting structure302, which may depend from another structure such as a ceiling or the canopy of a petroleum refill station.

The mounting structure302comprises four walls302aforming a rectangular box, square in the depicted embodiment. The mounting structure302further comprises a face plate304extending between the four walls302aslightly above their lower distal ends302b. The face plate304lies generally horizontal and defines a face plate aperture306. The face plate304can be separate from the walls302aor extend integrally from the walls302as depicted inFIG. 7B. The mounting structure302can be a pre-existing mounting structure in which a different luminaire had been installed or can be newly constructed for installation of a luminaire such as the luminaire100. However, the mounting assembly300finds particular use for installing modern LED-based luminaires (such as luminaire100) in mounting structures such as mounting structure302which is typical for housing older model luminaires such as HID or incandescent luminaires.

The mounting apparatus300comprises a mounting plate308mounted to the back of a luminaire, such as luminaire100. The mounting plate308optionally defines a mounting plate aperture308ato allow portions of the luminaire to project through. In the depicted example, the driver column146of the previously described luminaire100is allowed to project through the mounting plate308due to the aperture308a. Flanges308bextend upward from each edge of the mounting plate308a short distance to contact, or come close to contacting, the mounting structure302when installed. A hinge flange308cextends from a first of the flanges308band comprises an extending portion308c′ and wings308c″ extending from opposing sides of the extending portion308″. The extending portion308c′ does not extend to the ends of the first of the flanges308b, but instead leaves clearance on both ends. The wings308c″ extend beyond the ends of the first of the flanges308band beyond the edges of the corresponding aperture306of the mounting structure face plate304. In this configuration, the luminaire (such as luminaire100) may hang from the mounting structure302by the wings308c″ and may rotate about those wings308c″. The clearance left on both ends of the extending portion308c′ provides clearance between the extending portion and the edges of the corresponding aperture306during rotation. During installation, this structure allows an installer to connect the wiring of the luminaire to the power source in the mounting structure302. The mounting plate308can be mounted to the luminaire by screws or other hardware.

A catch310optionally extends from the mounting plate308adjacent to a second of the flanges308bextending from the mounting plate308on a side opposite to the first of the flanges308bfrom which the hinge flange308cextends. The catch310comprises a stem310aand a hook310bextending from the flange. In the depicted embodiment, stem310ais mounted to the mounting plate308and extend upward to a stem distal end310c, while the hook310bextends downward from the stem distal end310cangled toward the face plate302and extending to a hook distal end310dthat lies outside of the face plate aperture306such that when the luminaire100is rotated downward from the mounting structure302, the hook catches the face plate304and prevents the luminaire100from rotating further. A person seeking to rotate the luminaire100further may bend the stem310ainward a distance sufficient to allow the hook distal end301dto pass the face plate304. When rotating the luminaire100into the mounting structure, the angle of the hook310bcauses the stem310ato deflect inward as the hook310bslides past the face plate304, allowing the hook310bto pass the face plate304and spring back to an unbiased position after passing the face plate304. While the mounting apparatus300is beneficial without the optional catch310, the catch310is preferable for the above discussed benefits. Other embodiments of a catch are also contemplated.

One or more lock wings312are optionally mounted to one lock screw314each, which extends vertically through the luminaire100and the mounting plate308at a location adjacent to the second of the flanges308bextending from the mounting plate308on a side opposite to the first of the flanges308bfrom which the hinge flange308cextends. In the depicted embodiment, the mounting apparatus300comprises two lock wings312, each mounted to one lock screw314. Each lock screw314comprises a head314alocated at the face of the luminaire100, making the head314aaccessible when the mounting apparatus300is in the closed position depicted inFIGS. 7A, 7B and 7D(i.e. fully mounted to the mounting structure302). The lock screw314also comprises a threaded shaft314bextending through the luminaire100, through the mounting plate308and far enough above the mounting plate308such that it extends above the mounting structure face plate304when the mounting apparatus300is in the closed position.

Each lock wing312comprises a lock arm312aand a stop arm312bconnected by a bridge member312c. In the depicted embodiment, the lock wing312is constructed of sheet metal bent into a U-shaped configuration in which the lock arm312aconstitutes one leg of the U, the stop arm312bconstitutes the other leg of the U and the bridge member312cconstitutes the base of the U. In the depicted embodiment, an optional strengthening flange312dextends along and perpendicular to the lock arm312ato provide structural rigidity to the lock arm312. Each of the lock arm312aand the stop arm312bdefine a screw aperture312efor allowing the screw shaft314bto pass through. Optionally, one or both of the screw apertures312eis threaded so that the lock wing312can be threaded onto the screw shaft314b. Alternatively, or in addition, the lock wing312can be mounted to the screw shaft314bby other means, such as, by way of example only, adhesive.

Each lock wing312is mounted on the screw shaft314bat a distance from the screw head314athat will locate the lock arm312aslightly above the mounting structure face plate304. In this configuration, each lock wing312can be rotated about the central axis of its corresponding screw314by rotating the screw head314aof the corresponding screw314. Rotating the lock wing312can bring the lock arm312aover the mounting structure face plate304or over the aperture306defined in the mounting structure face plate304. When the lock arm312ais over the mounting structure face plate304, the lock arm312aprevents the luminaire100from rotating about the wings308c″ of the hinge flange308c, thus keeping the luminaire100secure to the mounting structure302. However, when the lock arm312ais over the aperture306defined in the mounting structure face plate304, the luminaire100may freely rotate about the wings308c″ of the hinge flange308c, thus allowing access to the luminaire100or removal of the luminaire100from the mounting structure100(with the above described manipulation of the optional catch310, if present). In this configuration, locking and unlocking the luminaire100to the mounting structure302requires only a ninety degree (90°) rotation of the screw head314a. The stop arm312bassists a person seeking to lock the luminaire100to the mounting structure302by contacting the adjacent mounting plate flange308bbefore the lock arm312ahas rotated too far. In this manner, the stop arm312bstops rotation of the lock wing312at the appropriate location so that it does not continue rotation and end up over the face plate aperture306. In the embodiment in which one or more of the screw apertures312eof the lock wing312are threaded to the screw shaft314b, the stop arm312bprevents rotation of the lock wing312and continued advancement of the screw314would draw the lock wing312closer to the screw head314adrawing the luminaire100closer to the mounting structure face plate304, allowing a person to tighten the luminaire100up against the mounting structure face plate304, or leave an gap there between at the option of the person.FIG. 7Bdepicts one lock wing312in the locked position and one lock wing312in the unlocked position. Other configurations and operations of the lock wings312are contemplated.

Optionally, the driver and/or other utilities can be mounted to the mounting plate308. In the depicted exemplary embodiment, the mounting plate308comprises a driver flange308dextending upward from the mounting plate and the utilities are attached thereto. By extending the driver flange308dupward of the mounting plate, the driver is separated from the luminaire housing to remove the heat of the utilities from the housing. The driver flange308dmay also act as a heat dissipation fin to dispel heat from the luminaire housing into the mounting apparatus300.

FIGS. 7F and 7Gdepict optional mounting structure extensions316a,316bthat may be mounted to the inner edge of the mounting structure face plate aperture306to extend the edges of that aperture306inward if slightly larger than desired for an appropriate fit with the mounting apparatus300. In operation, the mounting structure extensions316a,316bare slide over the inner edge of the aperture360onto the face plate to provide a new aperture appropriately sized.

The LEDs of this exemplary embodiment can be of any kind, color (e.g., emitting any color or white light or mixture of colors and white light as the intended lighting arrangement requires) and luminance capacity or intensity, preferably in the visible spectrum. Color selection can be made as the intended lighting arrangement requires. In accordance with the present disclosure, LEDs can comprise any semiconductor configuration and material or combination (alloy) that produce the intended array of color or colors. The LEDs can have a refractive optic built-in with the LED or placed over the LED, or no refractive optic; and can alternatively, or also, have a surrounding reflector, e.g., that re-directs low-angle and mid-angle LED light outwardly. In one suitable embodiment, the LEDs are white LEDs each comprising a gallium nitride (GaN)-based light emitting semiconductor device coupled to a coating containing one or more phosphors. The GaN-based semiconductor device can emit light in the blue and/or ultraviolet range, and excites the phosphor coating to produce longer wavelength light. The combined light output can approximate a white light output. For example, a GaN-based semiconductor device generating blue light can be combined with a yellow phosphor to produce white light. Alternatively, a GaN-based semiconductor device generating ultraviolet light can be combined with red, green, and blue phosphors in a ratio and arrangement that produces white light (or another desired color). In yet another suitable embodiment, colored LEDs are used, such are phosphide-based semiconductor devices emitting red or green light, in which case the LED assembly produces light of the corresponding color. In still yet another suitable embodiment, the LED light board may include red, green, and blue LEDs distributed on the printed circuit board in a selected pattern to produce light of a selected color using a red-green-blue (RGB) color composition arrangement. In this latter exemplary embodiment, the LED light board can be configured to emit a selectable color by selective operation of the red, green, and blue LEDs at selected optical intensities. Clusters of different kinds and colors of LED is also contemplated to obtain the benefits of blending their output.

The various luminaires that have been discussed may be used as outdoor lighting canopies. Each may have within it a single circuit board that contains one or more power supplies, drivers, and long chains of low power LEDs. Examples of these are described in the following figures and text that describes them.

FIG. 8illustrates an example of a circuit that includes a driver801and a long chain of low power LEDs803that may be driven by the driver801, all of which may be on a single circuit board within an outdoor canopy light.

The driver801may be an integrated circuit, such as a DT3001 TB (made by Seoul Semiconductor). The driver801may receive a full wave rectified sign wave as input power by connecting the positive side of this to input pin4and the ground side to input pin2. This may be supplied, for example, by an AC line voltage that is delivered to an input connection804. A fuse805may protect the circuit from an overload. A full wave bridge rectifier807may rectify the AC line voltage. The current that is delivered by the full wave bridge rectifier807may be limited, such as by resistor pairs809and resistor pairs811in each leg of the rectified voltage which may have a low resistance, such as about 20 ohms each. The rectified and current-limited output from the full wave bridge rectifier807may be protected against surges in the AC line voltage by a transient voltage suppression diode (TVS)813and/or a metal oxide varistor (MOV)815. Operating points of the driver801may be set by various components, such as by a R_set resistor815and a R_bld resistor817.

The driver801may deliver a voltage-stepped, current-regulated output at its output, such as at its output pins11,10,9, and8, with an output pin2serving as a ground reference. The driver801may deliver current in a voltage-stepped sequence. The first step may provide a ground connection at pin11, the next step at pin10, the next step at pin9, and then the final step at pin8. The voltage may increase at each step in synchronism with increases in the full wave bridge rectified voltage input on pin4. The voltage may then step back down, first back to pin9, then back to pin10, and then finally back to pin11, again in synchronism with decreases in the full wave bridge rectified input voltage on pin4. The driver801may repeat this stepped up and then stepped down cycle during each rising and falling portion of each 180 degree segment of the full wave bridge rectified AC line input voltage.

The long chain of low power LEDs803may consist of a minimum of 36 or a minimum of 48 low power LEDs connected in series. Each LED may have a power rating that is no more than 1 watt or 0.6 watts. The LEDs may be of any type, such as a Nichia NFSW757D-v1 or NFSL757D-v1. They may emit white light or light of any desired color or color combination.

As can be seen inFIG. 8, the long chain of low powered LEDs803may be divided into sub-chains, with each sub chain being driven by one of the stepped outputs from the driver801. At least one sub-chain may have a minimum of 12 or 16 LEDs connected in series. No sub-chain may have less than 6 or 8 LEDs connected in series. Although only one chain of LEDs is shown inFIG. 8, multiple chains of LEDs may instead be connected in parallel to the various outputs of the driver801, or each additional chain of LEDs may be connected to a separate driver with separate or (partially or fully) shared support circuitry.

The design illustrated inFIG. 8and discussed above may not require any electrolytic capacitors and thus may not be susceptible to failures caused by defective electrolytic capacitors when they age.

FIG. 9illustrates an example of a circuit that includes multiple drivers801and901and a long chain of low power LEDs803that may be driven by multiple drivers801and901with their outputs connected in parallel, all of which may be on a single circuit board, all within an outdoor canopy light. The circuit inFIG. 9may be identical to the one shown inFIG. 8, except that the multiple drivers801and901are being used to drive the same chain of LEDs (or chains of LEDs if more than one chain of LEDs is connected in parallel). The driver901may be the same type as the driver801or different.

As also shown inFIG. 9, the additional driver901may have its own operating point setting resistors915and917, but otherwise may share the power supply and surge suppression components that are also used with the driver801and described above. Additional drivers and their associated operating point setting resistors may be added in parallel in the same way to provide added current-driving capability, which may be useful when multiple chains of LEDs are connected in parallel or to match the current needs of a single chain of LEDs.

FIG. 10illustrates an example of a block diagram of an outdoor canopy light1001that may use a single full wave bridge rectifier circuitry1013to supply power to multiple sets of driver circuitry/LED chain(s)1015,1017,1019,1021. The full wave bridge rectifier circuitry1013may generate a full wave bridge rectified AC signal, such as the one generated by the power supply illustrated inFIGS. 8 and 9. The full wave bridge rectifier circuitry1013may include the line voltage inputs804, the fuse805, and the full wave rectifier bridge rectifier807). Each of the driver circuitry/LED chain(s)1015,1017,1019,1021may include one or more drivers, such as the drivers801and/or901, the current limiting resistor pairs809and811, the voltage suppression diode (TVS)813, the metal oxide varistor (MOV)815, associated operating set point circuitry, such as the R_sets815and915, the R_blds817and917, and one or more long chains of low power LEDs, such as the long chain of low power LEDs803. All of the components may again be on a single circuit board, with the full wave bridge rectifier circuitry1013being in a central areas and each of the multiple sets of driver circuitry/LED chain(s)1015,1017,1019,1021being in one of the four quadrants One or more of these components may instead be placed in other locations. Separate full wave bridge rectifier circuitry may also instead be provided for each of the driver circuitry/LED chain(s) or for sub-groups of them. Similarly, a common set of the current limiting resistor pairs809and811, the voltage suppression diode (TVS)813, and the metal oxide varistor (MOV)815may also instead be used.

FIG. 11illustrates an example of one quadrant of a long chain of low power LEDs on a single circuit board1101. An example of one of these LEDs is LED1103. The light grey area on the circuit board is a foil pattern that may advantageously be used to connect the LEDs in series and that provides electrical connections1105,1107,1109, and1113to sub-chains within the chain.

FIG. 12illustrates an example of a single circuit board1201that may be placed within an outdoor canopy light that includes a centralized area1203which may contain an input connection for the AC line voltage and four quadrants. Each quadrant may include a long chain of low power LEDs, such as the long chain of low power LEDs1205,1207,1209, or1211. Each quadrant may also include its own power supply, driver(s) and operational set point components, such as in the areas1213,1215,1217, and1219of each quadrant.

Optics may be used to direct the light generated by the LEDs. Separate optics may be used for each LED or section of LEDs. Or all of the LEDs may share the same optics. The canopy lights that have been described may be used for any purpose, such as for outdoor lighting, such as in parking lots and gas stations.

For example, the component values that have been described may be ideal when the input line voltage is 120 VAC. However, other input line voltages may be used instead, such as 240 VAC. In this situation, the typical number of components and/or their values may be adjusted to compensate for this voltage change, as should readily be apparent to those skilled in the art. For example, the number or wattage of the LEDs per chain and sub-chain may be doubled.

All articles, patents, patent applications, and other publications that have been cited in this disclosure are incorporated herein by reference.

The phrase “means for” when used in a claim is intended to and should be interpreted to embrace the corresponding structures and materials that have been described and their equivalents. Similarly, the phrase “step for” when used in a claim is intended to and should be interpreted to embrace the corresponding acts that have been described and their equivalents. The absence of these phrases from a claim means that the claim is not intended to and should not be interpreted to be limited to these corresponding structures, materials, or acts, or to their equivalents.

The scope of protection is limited solely by the claims that now follow. That scope is intended and should be interpreted to be as broad as is consistent with the ordinary meaning of the language that is used in the claims when interpreted in light of this specification and the prosecution history that follows, except where specific meanings have been set forth, and to encompass all structural and functional equivalents.

Relational terms such as “first” and “second” and the like may be used solely to distinguish one entity or action from another, without necessarily requiring or implying any actual relationship or order between them. The terms “comprises,” “comprising,” and any other variation thereof when used in connection with a list of elements in the specification or claims are intended to indicate that the list is not exclusive and that other elements may be included. Similarly, an element preceded by an “a” or an “an” does not, without further constraints, preclude the existence of additional elements of the identical type.

None of the claims are intended to embrace subject matter that fails to satisfy the requirement of Sections 101, 102, or 103 of the Patent Act, nor should they be interpreted in such a way. Any unintended coverage of such subject matter is hereby disclaimed. Except as just stated in this paragraph, nothing that has been stated or illustrated is intended or should be interpreted to cause a dedication of any component, step, feature, object, benefit, advantage, or equivalent to the public, regardless of whether it is or is not recited in the claims.

The abstract is provided to help the reader quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, various features in the foregoing detailed description are grouped together in various embodiments to streamline the disclosure. This method of disclosure should not be interpreted as requiring claimed embodiments to require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus, the following claims are hereby incorporated into the detailed description, with each claim standing on its own as separately claimed subject matter.