发明内容:
[0003]The Inventors, via previous innovative designs for lighting modules, have recognized and appreciated lighting modules that integrate a LED light source, a driver, and a standardized connector into a single package provide users a convenient, easy-to-handle device to facilitate installation, maintenance, and/or replacement. However, the Inventors have also recognized conventional lighting modules are often limited in terms of customizability, performance, and ease of assembly.
[0004]First, conventional lighting modules typically output light with a fixed emission profile. In other words, the spatial and/or angular distribution of light provided by the lighting module is not adjustable. If a change to the emission profile is desired, the entire lighting modules is typically replaced with another lighting module that provides the desired emission profile. For example, a conventional lighting system may include a first lighting module that provides ambient lighting (e.g., general illumination of a room). If a user wishes to reconfigure the lighting system to provide task lighting (e.g., illumination of a particular portion of the room), the user should remove the first lighting module and then install a second lighting module that provides task lighting, which is often purchased separately.
[0005]Second, it is also often desirable for a lighting system to include a dimmer to provide the user the ability to adjust the brightness of the light output. Various dimmer protocols are often deployed in lighting systems, such as phase dimming (e.g., triode for alternating current (TRIAC) dimmers) or 4-wire dimmers (i.e., 0-10V dimmers). For lighting systems that include a LED light source, the driver typically includes circuitry tailored for a particular dimmer protocol. However, conventional drivers that are compatible with dimmers are typically standalone devices that are installed separately from the lighting module. For example, in a conventional recessed lighting system, the driver is often placed in a junction box, which is inaccessible after installation of the lighting system. As a result, the lighting system may be constrained to a particular dimmer protocol. If a user wishes to change the driver to accommodate a different dimmer protocol, portions of the environment (e.g., the ceiling) may need to be removed and the lighting system may need to be uninstalled to provide the user access to the driver contained within the junction box.
[0006]Third, the light output provided by conventional lighting modules is typically limited by a combination of the heat generation from the LED light source and/or the circuitry in the driver module and inadequate cooling of the lighting module. In other words, conventional lighting modules are unable to provide higher light outputs without various components in the LED light source and/or the circuitry of the driver module overheating (e.g., an operating temperature greater than 125° C.), which reduces the operational lifetime of the lighting module or, in some instances, creates a potential fire hazard in the environment.
[0007]Fourth, conventional lighting modules also often include a ground connection to protect the electronic circuitry in the driver and/or the light source from a surge in electricity. However, the ground connection, which is typically a wire, is often attached to an exterior surface of the module housing (e.g., the heat sink). Although the housing may be electrically conductive, the driver circuitry may not have a direct electrical connection to the housing, thus the ground connection may only provide limited protection against an electrical surge.
[0008]Fifth, conventional lighting modules are also cumbersome to assemble and prone to assembly errors, which may affect the operation and/or performance of the lighting module. For example, previous lighting modules often include a chip on board (COB) light emitting diode (LED) as the light source, which is mounted manually to a flat, thermally dissipating surface of a heat sink via thermal paste. The position and alignment of the light source in the lighting module may thus vary depending on the precision in which the light source is attached to the heat sink. For lighting modules that include a collimating optic (e.g., lighting modules configured for task lighting), small variations in the position and alignment of the light source may have a substantial effect on the direction and divergence of the output light.
[0009]In another example, the light source in previous lighting modules is typically soldered by hand to electrical wiring in order to receive electrical power from a driver. The quality of the hand soldered joint depends, in part, on the skill of the assembler and, hence, may also vary between lighting modules. A low-quality solder joint may detrimentally affect the operation of the light source (e.g., higher noise, excess heating, lower electric current inputs) and lead to premature failure of the lighting module once deployed in the field.
[0010]In yet another example, the various components of previous lighting modules are often assembled using numerous fasteners. For instance, the optical components (e.g., a reflector, a lens) and the housing for the driver are often mounted to a heat sink using multiple screw fasteners. Furthermore, the size and type of fasteners (e.g., a Phillips screw, a hex screw, a flathead screw) often vary depending on the component. The inclusion of multiple, different fasteners increases the manufacturing costs of the lighting module as well as the time and difficulty for assembly due to the assembler having to fasten each screw one at a time and the different tools the assembler should use for the different fasteners.
[0011]In view of the foregoing, the present disclosure is directed to various inventive implementations of a lighting module for a lighting system (e.g., a recessed light, a cylinder light, a downlight, a landscape light, a flood light, an in-ground light) that provides field-changeable optics, an integrated driver with circuitry to accommodate one or more dimmer protocols, improved thermal dissipation enabling higher light outputs, an internal ground connection for the driver and/or the LED light source, and numerous tool-less mounting features for greater ease of assembly.
[0012]In some implementations, the lighting module includes a heat sink with a sidewall and a partition that defines two separate cavities to contain a light source and a driver module, respectively. The driver module may include a driver housing to support electronic circuitry (also referred to herein as “driver circuitry”). The driver circuitry typically receives AC power and outputs DC power to the LED light source. In some implementations, the driver circuitry may also receive a DC control signal to dim the light output provided by the LED light source. In some implementations, the driver module may also include a driver insulator, which may work in tandem with the driver housing to provide a barrier to physically separate the electronic circuitry from the heat sink. The lighting module may also include an optical assembly that includes one or more optical elements to redirect the light emitted by the light source in order to provide a desired emission profile (i.e., a desired spatial and/or angular light distribution).
[0013]In one aspect, the optical assembly may be readily field changeable. This may be accomplished, in part, by the optical assembly including optical elements (e.g., a reflector, an optical lens) that are readily removable from the lighting module, in part, by using tool-less mounting mechanisms. For example, the optical assembly may include a cover lens that is coupled to the heat sink via one or more snap-fit connections. Specifically, the cover lens may include two snap-fit connectors that are shaped such that a user may readily actuate the snap-fit connectors by hand in order to remove and replace the optical assembly. In some implementations, each snap-fit connector may be sufficiently actuated to allow removal of the cover lens from the heat sink when a force having a magnitude of about 25 pounds is applied to the snap-fit connector.
[0014]The cover lens may refract the emitted light to produce a desired spatial and/or angular light distribution. In some implementations, the cover lens may be patterned and/or textured to diffusely scatter at least a portion of the emitted light. In some implementations, the optical assembly may further include a substantially flat optical element (e.g., a diffuser, a filter) that is coupled to the cover lens via, for example, a snap-fit connection and/or held in place by another optical component. In this manner, the flat optical element and the cover lens may be installed and/or removed together from the lighting module as a single assembly.
[0015]In some implementations, the optical assembly may further include a reflector that is snap-fit connected to the cover lens such that the optical assembly is removably coupled to the heat sink as a single assembly. The reflector, which may be disposed within the same cavity as the LED light source, may redirect light emitted at larger emission angles towards the opening defined by the top end of the sidewall. It should be appreciated that, in some implementations, the optical assembly may include an optical lens coupled directly to the cover lens instead of a reflector.
[0016]In some implementations, the optical assembly may include an optical lens (e.g., a folded optical element) that is mounted to the heat sink separately from the cover lens. For example, the optical assembly may include an optic holder to support the optical lens and to provide mounting features (e.g., a twist-and-lock connection mechanism) to couple the optical lens to the heat sink. In this manner, the optical lens may be more precisely aligned and positioned to the heat sink in order to provide a desired spatial and/or angular light distribution. The optic holder may also be reflective in order to redirect and/or recycle stray light from the optical lens to maintain or increase the light coupling efficiency of the optical assembly (i.e., the ratio of the amount of light exiting the lighting module and the amount of light emitted by the LED light source). The inclusion of the optic holder to mount the optical lens to the heat sink separately from the cover lens may allow the user may replace only the cover lens and/or the flat optical element to change, for example, the clarity or haze of the output light by changing the diffuser or the color of the output light by changing the filter. It should be appreciated that, in some implementations, the optical assembly may include reflector coupled to the heat sink separately from the cover lens instead of an optical lens.
[0017]In example implementations, the driver circuitry of the lighting module (e.g., conversion of an AC voltage from a building mains electrical supply to a DC voltage suitable for providing power to an LED light source) may be implemented to facilitate appreciable dimming of light output, without perceivable flicker, via the output of a conventional TRIAC dimmer coupled to driver circuitry of the lighting module. Examples of driver circuitry configured for TRIAC-based dimming described further below include, or are derived from, various circuit architectures disclosed in U.S. application Ser. No. 16/561,898, filed Sep. 5, 2019, entitled “METHODS AND APPARATUS FOR TRIAC-BASED DIMMING OF LEDS,” now U.S. Pat. No. 10,616,968, issued Apr. 7, 2020, is incorporated by reference herein in its entirety. Pursuant to such driver circuitry, existing triac-based dimmers from a variety of manufacturers (and different models from a given manufacturer) may be used to effectively control (increase or decrease) the light output of a lighting module in a relatively smooth fashion and over an appreciable range of light output (e.g., between full power light output and relatively small percentages of full power light output, such as less than 5%, less than 2%, or less than 1%) without shimmer or flickering effects.
[0018]In some example implementations, driver circuitry of the lighting module may be implemented to facilitate dimming of light output via 0-10V dimming. As would be readily appreciated in the art, 0-10V dimming is a lighting control method that produces varying light level outputs based on a direct current (DC) control voltage between 0 and 10 volts.
[0019]In yet other examples, driver circuitry of the lighting module is configured to adjust the light output (e.g., intensity) of the lighting module as well as correlated color temperature (CCT) of the light output. For driver circuitry configured for CCT control, in inventive aspects one or both of the AC half cycles of input AC voltage are employed to enable a phase dimmer to convey desired CCT in one half cycle and desired intensity in the other half cycle. The information is conveyed by varying the time that the phase cut dimmer conducts during the positive and negative half cycles. A controller of the driver circuitry decodes the incoming AC phase-cut waveform and converts it to two distinct signals representing intensity and CCT. Detailed examples of driver circuitry for CCT control are provided in U.S. Provisional Application No. 63/224,469, filed Jul. 22, 2021, entitled “METHODS AND APPARATUS FOR ENCODING ONE OR MORE HALF-CYCLES OF AN AC WAVEFORM TO CONTROL A LIGHTING FIXTURE,” which is hereby incorporated herein by reference.
[0020]In implementations where the lighting module includes a ground connection, the lighting module may include a first ground cable that electrically couples the electronic circuitry of the driver module to the heat sink. A second ground cable may then connect the heat sink to an external ground (e.g., the housing of a lighting system). Thus, the lighting module may provide a direct ground path for the electronic circuitry to discharge in the event of an unwanted electrical surge in the lighting system. In some implementations, the first and second ground cables may be connected to the heat sink at the same location using a single screw fastener. In some implementations, potting material may also be included to electrically insulate and seal the electronic circuitry within the driver housing.
[0021]In another aspect, the lighting module may provide multiple thermal pathways to dissipate heat generated by the light source and/or electronic circuitry contained in the driver module to the surrounding environment and, in particular, the environment being illuminated (e.g., the space within which the lighting system is installed). For example, the partition of the heat sink may provide a thermal pathway to transfer heat generated by the LED light source to the sidewall and thereafter towards a top end of the sidewall defining an opening through which light from the light source exits the lighting module and into the environment being illuminated. Thus, the heat from the light source may be directed towards the portion of the lighting module proximate to the illuminated environment and subsequently dissipated into the environment via, for example, convection.
[0022]The partition may include a recessed section that surrounds and partially encloses the light source and the light source holder to position the light source at a desired distance from the various optical components of the optical assembly. In some implementations, the partition may further include a tapered section that joins the recessed section to the top end of the sidewall of the heat sink. The combination of the recessed section and the tapered section may provide a thermal pathway to transport the heat generated by the LED light source to the sidewall via heat conduction. It should be appreciated that, in some implementations, the partition may not be tapered, but instead may extend horizontally to the sidewall. Thus, the heat generated by the light source may conduct to a portion of the sidewall between the top end and a bottom end and then conduct towards the top end of the sidewall.
[0023]In some implementations, the heat sink may include a flange to provide a mechanical interface to mount the lighting module to a housing of a lighting system (e.g., a can housing, a junction box) and/or to couple a trim to the lighting module. The flange may be formed on the top end of the sidewall and may thus provide an additional surface to dissipate heat from the lighting module. For example, a trim may be coupled to the flange of the heat sink. In this manner, the heat generated by the LED light source may be transported to the top end of the heat sink via the partition and/or the sidewall and thereafter to the trim via heat conduction. The trim, in turn, may dissipate heat to the illuminated environment via, for example, convection.
[0024]The driver circuitry of the driver module may also generate heat during operation. In particular, specific circuit elements of the driver circuitry, such as a transformer, may generate more heat than other circuit elements, which may lead to hot spots in the driver circuitry (e.g., localized portions of the driver circuitry where the temperature is higher than other portions of the driver circuitry). In some implementations, the potting material disposed around the electronic circuitry in the driver housing may reduce or, in some instances, mitigate the creation of hot spots in the driver circuitry by providing a medium to locally dissipate heat from various circuit elements. Said in another way, the potting material may be sufficiently thermally conducting to maintain the temperature of the circuit elements, such as the transformer, below 125° C. during operation.
[0025]In some implementations, a portion of the heat generated by the driver circuitry may dissipate convectively to the surrounding space within the housing containing the lighting module. In some implementations, another portion of the heat generated by the driver circuitry may dissipate directly to the heat sink due to physical contact between some of the circuit elements and portions of the heat sink where the risk of short circuiting is low. For example, the transformer may directly contact the partition of the heat sink. In some implementations, yet another portion of the heat generated by the driver circuitry may be transported to the sidewall of the heat sink through a sidewall of the driver housing. In some implementations, most of the heat generated by the driver circuitry may dissipate through the sidewall of the driver housing and the sidewall of the heat sink. In other words, the thermal pathway passing through the sidewall of the driver housing and the sidewall of the heat sink may have an appreciably lower thermal resistance than other thermal pathways.
[0026]Depending on the desired output, the driver housing may be formed of a polymer or a metal. A polymeric driver housing may be used for lighting modules that provide relatively lower light outputs while a metallic driver housing may be used for lighting modules that provide relatively higher light outputs. For example, the polymeric driver housing may be used for lighting modules that provide a light output less than or equal to 1250 lumens while a metallic driver housing may be used for lighting modules that provide a light output greater than or equal to 1250 lumens. It should be appreciated the 1250 lumen threshold is exemplary and may change over time due to improvements in the efficiency of the LED light source and the driver electronics. More generally, the choice between a polymeric or a metallic driver housing may depend on which driver housing is able to maintain the driver circuitry at a desired operating temperature (e.g., less than or equal to 125° C.).
[0027]In implementations where a metallic driver housing is used, the driver module may further include a thin electrically insulating film (e.g., a mylar film) that lines the interior surfaces of the driver housing and/or the surfaces of the driver circuitry including the printed circuit board to electrically insulate the driver circuitry without appreciably increasing the thermal resistance between the driver circuitry and the sidewall of the heat sink. In some implementations, the insulating film may be perforated with openings to allow potting material to fill any gaps between the driver circuitry and the driver housing. In some implementations, the driver module may only include the potting material to electrically insulate driver circuitry from the metallic driver housing.
[0028]The lighting module may also support one or more airways for air to flow through the interior of the lighting module in order to convectively cool the various components of the lighting module. For example, the airway may provide a path for cool air to enter the lighting module where the air is then heated by the light source and/or the driver. The hot air may then exit the lighting module to dissipate the heat into the surroundings. In this manner, the lighting module may provide cooling using both internal heat conduction and convection.
[0029]In another aspect, the lighting module may include several tool-less mounting features to improve the ease of assembly by reducing the number of parts (e.g., fasteners) and the number of tools for assembly. For example, the cover lens in the optical assembly, as described above, may include snap-fit connectors that are configured to be actuated by hand. A reflector and/or an optical element may also be separately mounted to the heat sink (or a light source holder) via one or more twist and lock connectors and aligned via one or more registration features. In another example, the driver housing may be coupled to the heat sink via one or more snap-fit connectors. In some implementations, the driver insulator may not be held in place, but instead may float within the driver module. In some implementations, the driver module may also be readily replaced in the lighting module without changing the optical assembly.
[0030]In another example, the lighting module may include a light source holder to align and position the light source in the heat sink. The light source holder may include poke-in connectors to electrically couple the respective contacts of the light source to corresponding wires (e.g., positive and negative leads) from the driver module. The poke-in connector may include an integrated wire restraint that prevents the removal of a wire after the wire is inserted into the poke-in connector. In this manner, the wires may be connected to the light source without soldering. It should be appreciated that, in some implementations, the light source holder may be tailored to provide terminal pads to solder wires directly to the terminals of the LED light source. In some implementations, the light source holder may also be field-changeable in order to support the installation of different light sources (e.g., different LED COB chips) in the lighting module.
[0031]Based on the above mounting features, the various components of the lighting module may be assembled using few, if any, fasteners. For example, the lighting module may include a fastener to electrically and physically couple the electrical ground wires in the lighting module to the heat sink. One or more fasteners may couple the light source holder to the heat sink instead of the snap-fit connectors. In some applications, such as retrofit lighting systems, lighting fixtures with remote-mounted power supplies, or lighting fixtures with low voltage inputs such as through a power over Ethernet (PoE) connection, a ground connection to the lighting module may not be included. Furthermore, the light source holder may be coupled to the heat sink via another mechanism, such as one or more snap-fit connections. Therefore, in some implementations, the light module may be assembled without the use of any fasteners and/or tools, thus greatly simplifying assembly.
[0032]It should be appreciated that all combinations of the foregoing concepts and additional concepts discussed in greater detail below (provided such concepts are not mutually inconsistent) are contemplated as being part of the inventive subject matter disclosed herein. In particular, all combinations of claimed subject matter appearing at the end of this disclosure are contemplated as being part of the inventive subject matter disclosed herein. It should also be appreciated that terminology explicitly employed herein that also may appear in any disclosure incorporated by reference should be accorded a meaning most consistent with the particular concepts disclosed herein.
具体实施方式:
[0131]Following below are more detailed descriptions of various concepts related to, and implementations of, lighting modules with field-changeable optical assemblies, integrated drivers supporting different dimmer protocols, improved heat dissipation, tool-less mounting features, and structural features/components for alignment and assembly of the various components therein. It should be appreciated that various concepts introduced above and discussed in greater detail below may be implemented in multiple ways. Examples of specific implementations and applications are provided primarily for illustrative purposes so as to enable those skilled in the art to practice the implementations and alternatives apparent to those skilled in the art.
[0132]The figures and example implementations described below are not meant to limit the scope of the present implementations to a single embodiment. Other implementations are possible by way of interchange of some or all of the described or illustrated elements. Moreover, where certain elements of the disclosed example implementations may be partially or fully implemented using known components, in some instances only those portions of such known components that are necessary for an understanding of the present implementations are described, and detailed descriptions of other portions of such known components are omitted so as not to obscure the present implementations.
[0133]In the discussion below, various examples of inventive lighting modules are provided, wherein a given example or set of examples showcases one or more particular features of a heat sink, a driver module, driver circuitry, a light source, a light source holder, and an optical assembly. It should be appreciated that one or more features discussed in connection with a given example of a lighting module may be employed in other examples of lighting modules according to the present disclosure, such that the various features disclosed herein may be readily combined in a given lighting module according to the present disclosure (provided that respective features are not mutually inconsistent).
[0134]Certain dimensions and features of the lighting module are described herein using the terms “approximately,”“about,”“substantially,” and/or “similar.” As used herein, the terms “approximately,”“about,”“substantially,” and/or “similar” indicates that each of the described dimensions or features is not a strict boundary or parameter and does not exclude functionally similar variations therefrom. Unless context or the description indicates otherwise, the use of the terms “approximately,”“about,”“substantially,” and/or “similar” in connection with a numerical parameter indicates that the numerical parameter includes variations that, using mathematical and industrial principles accepted in the art (e.g., rounding, measurement or other systematic errors, manufacturing tolerances, etc.), would not vary the least significant digit.
[0135]The lighting modules described herein may generally be used in a variety of lighting systems installed into a ceiling, wall, or floor space of an environment or installed onto a surface of a drywall panel, a wood panel, and/or flooring forming the ceiling, wall, and floor, respectively. Although the lighting modules may be described herein in the context of a particular lighting system installation, it should be appreciated the lighting module may be used in a different lighting system installation in the same or similar manner. For example, the lighting module may be installed into a housing or an enclosure of different lighting systems using the same mechanisms disclosed herein.
A Lighting Module with a Reflector
[0136]FIGS. 1A-1M show an exemplary lighting module 1000a for a lighting system with an optical assembly 1500a that includes a reflector 1540. As shown, the lighting module 1000a may include a heat sink 1100 with a sidewall 1110 and a partition 1120 that together define cavities 1102 and 1104.
[0137]The cavity 1102 may contain an LED light source 1300 to emit light, a light source holder 1400a to align and couple the light source 1300 to the heat sink 1100, and the optical assembly 1500a to redirect the light emitted by the light source 1300 to produce a desired emission profile. For example, the reflector 1540 may be used, in part, to redirect the light emitted by the light source 1300 to provide general ambient lighting of an environment where the output light has a beam angle greater than or equal to about 90 degrees. The optical assembly 1500a may also be field-changeable as will be discussed in more detail below.
[0138]The cavity 1104 may contain a driver module 1200 with driver circuitry 1210 (also referred to herein as “circuitry 1210”) to receive electrical power from an external power source (e.g., a building electrical supply system, another lighting system in a daisy-chain configuration) and to supply electrical power to the light source 1300. The driver module 1200 may include various electrical wires to supply and/or transfer electrical power (e.g., an electrical cable 1020, electrical cables 1030a and 1030b) and to provide a ground connection (e.g., ground cables 1010 and 1014). The electrical cables 1020, 1030a, and 1030b are also referred to herein as power cables 1020, 1030a, and 1030b.
[0139]The lighting module 1000a may generally be shaped and/or dimensioned to facilitate installation into a variety of different lighting systems with different-sized housings (also referred to herein as “enclosures”). For example, the lighting module 1000a may be installed into various standard-sized housings including, but not limited to, a 3″ junction box, a 4″ junction box, a 3″/4″ combo junction box, a 3/0 junction box, a 4/0 junction box, and a can housing for a 4-10 inch recessed lighting fixture. The lighting module 1000a may also be installed into housings for a surface mounted lighting fixture or a lighting fixture that includes a housing that extends from a wall (e.g., a wall sconce).
[0140]In some implementations, the lighting module 1000a may be directly mounted to the housing of a lighting system. For example, standard housings typically include one or more tabs and/or posts disposed within a cavity of the housing or at an open end of the housing with fastener openings. The lighting module 1000a and, in particular, the heat sink 1100 may include corresponding opening(s) (e.g., holes 1144 on a flange 1140 of the heat sink 1100a) that align with the opening(s) of the housing. Corresponding fasteners may thus be inserted through the respective openings of the lighting module 1000a and the housing to securely couple the lighting module 1000a to the housing.
[0141]In some implementations, the lighting module 1000a may be indirectly mounted to the housing of a lighting system. For example, the lighting module 1000a may include mounting features to support a trim (e.g., a twist-and-lock connector 1142 on the flange 1140 of the heat sink 1100). During installation, the lighting module 1000a may be first coupled to a trim. The lighting module 1000a and the trim may then be inserted into the housing together. The trim may include a separate coupling mechanism, such as one or more friction clips or spring clips, to securely couple the trim and, by extension, the lighting module 1000a to the housing.
[0142]The lighting module 1000a may be dimensioned to be sufficiently compact to accommodate smaller-sized housings while providing a mounting interface that conforms with standard mounting features for the housing (e.g., the tabs of a junction box). For example, the lighting module 1000a may have a characteristic width, defined as the largest lateral extent of the lighting module 1000a (e.g., the exterior width (wext,2) of the flange 1140 as shown in FIG. 1F), of about 3⅞ inches. The exterior width of the sidewall 1110 (wext,1) may be about 3 inches. Thus, the exterior width of the lighting module 1000a may range between about 3 inches and about 3⅞ inches. More generally, the exterior width of the lighting modules described herein may range between about 3 inches and about 4 inches. The lighting module 1000a may also have an exterior height (hext), corresponding to the largest distance between the top and bottom sides of the lighting module 1000a (e.g., the distance between a base 1234 of the driver housing 1230 and the top-most portion of the cover lens 1510 in the optical assembly 1500a) of about 1 7/16 inches. More generally, the exterior height hext of the lighting module 1000a may range between about 1 inch and about 2½ inches.
[0143]The term “about,” when used to describe the various dimensions of the lighting module 1000a, is intended to cover manufacturing tolerances. For example, “about 3 inches” may correspond to the following dimensional ranges: 2.97 to 3.03 inches (+/−1% tolerance), 2.976 to 3.024 inches (+/−0.8% tolerance), 2.982 to 3.018 inches (+/−0.6% tolerance), 2.988 to 3.012 inches (+/−0.4% tolerance), 2.994 to 3.006 inches (+/−0.2% tolerance).
[0144]FIGS. 2A and 2B show additional views of the driver module 1200 and, in particular, the circuitry 1210. As noted above, the circuitry 1210 receives electrical power from an external power source (e.g., the power supply system of a building, another lighting system) via the electrical cable 1020 and supplies electrical power to the light source 1300 via electrical cables 1030a and 1030b. The circuitry 1210 may generally receive alternating current (AC) and/or direct current (DC) at various operating voltages and/or currents.
[0145]For example, the lighting module 1000a may be installed in an indoor lighting system (e.g., a recessed light, a cylinder light, a downlight), which typically receives AC current as the input (e.g., a “mains” voltage from the electrical system of a building). In another example, the lighting module 1000a may also be installed in an outdoor lighting system (e.g., a landscape light, a flood light, an in-ground light), which typically receives DC current as the input. Furthermore, the circuitry 1210 may be compatible with a range of operating voltages including, but not limited to, low operating voltages (e.g., voltages less than 50V) and high operating voltages (e.g., voltages greater than 50V). In some implementations, the voltage input may also vary based on the application and the type of lighting system. For example, the lighting module 1000a may be deployed in a low voltage lighting system (e.g., household lighting, landscape lighting, office lighting, and/or hospitality lighting using a 12V input) or a high voltage lighting system (e.g., security lighting, public lighting using a 120V line voltage input or a 277V line voltage input).
[0146]The driver circuitry 1210 may then convert and/or process the electrical input into a form suitable to power the LED light source 1300. For example, the circuitry 1210 may supply DC current to the light source 1300 at a voltage corresponding to the operating voltage of the light source 1300. In some implementations, the circuitry 1210 may output DC current at voltages ranging between about 0 V and about 10 V. More generally, the circuitry 1210 may output DC current at voltages ranging between about 0 V and about 60 V.
[0147]In some implementations, the circuitry 1210 may also facilitate dimming of the LED light source 1300. The driver circuitry 1210 may provide support for various dimming protocols including, but not limited to, phase dimming (e.g., triode for alternating current (TRIAC) dimming, electronic low voltage (ELV) dimming), 4-wire dimming (e.g., 0-10V dimming), and pulse width modulated (PWM) dimming. In some examples, both the light output (e.g., intensity of light) as well as the correlated color temperature (CCT) of the light output may be controlled via the circuitry 1210.
[0148]For example, in one implementation the circuitry 1210 converts an AC voltage (e.g., from a building mains electrical supply) to a DC voltage suitable for providing power to an LED light source) and facilitates appreciable dimming of light output, without perceivable flicker, based on the output of a conventional TRIAC dimmer coupled to the circuitry 1210. Examples of circuitry 1210 configured for TRIAC-based dimming include, or are derived from, various circuit architectures disclosed in U.S. application Ser. No. 16/561,898, filed Sep. 5, 2019, entitled “METHODS AND APPARATUS FOR TRIAC-BASED DIMMING OF LEDS,” now U.S. Pat. No. 10,616,968, issued Apr. 7, 2020 (incorporated by reference herein in its entirety). Pursuant to such driver circuitry, existing triac-based dimmers from a variety of manufacturers (and different models from a given manufacturer) may be used to effectively control (increase or decrease) the light output of a lighting module in a relatively smooth fashion and over an appreciable range of light output (e.g., between full power light output and relatively small percentages of full power light output, such as less than 5%, less than 2%, or less than 1%) without shimmer or flickering effects.
[0149]FIGS. 17A and 17B show respective portions of example circuitry 1210A derived in part from the circuit architectures disclosed in U.S. Pat. No. 10,616,968 referenced immediately above. In particular, FIG. 17A illustrates a primary side 1210A-1 of the circuitry 1210A and FIG. 17B illustrates a secondary side 1210A-2 of the circuitry. The overall functionality and circuit topology of the primary side 1210A-1 shown in FIG. 17A is described in detail in U.S. Pat. No. 10,616,968. Regarding the secondary side 1210A-2 of the circuitry shown in FIG. 17B, perceivable flicker is substantially mitigated in the light output via a timed addition of capacitance across the DC voltage that provides power to the LED light source. In particular, when a DC voltage is present between the terminals +LED and −LED to provide power to the LED light source, the capacitor C20 is connected between these terminals and charges relatively quickly to provide moderate flicker suppression. After approximately 60 seconds, capacitors C30 and C9 charge up through resistor R40 (with a relatively large RC time constant). Transistor Q7 is a voltage buffer generating a voltage 0.6V less than that across capacitors C30 and C9. Resistors R41 and R42 divide the voltage generated by transistor Q7 and apply the divided voltage to a MOSFET Q9. When the divided voltage reaches the turn-on threshold voltage of Q9 (e.g., approximately 3V) then Q9 turns on and connects additional capacitor C10 to further aid with flicker suppression. To prevent a premature switching-in of capacitor C10 (which may create a dip in the output voltage between the terminals +LED and −LED), resistor R43 provides a relatively slow pre-charging path for capacitor C10 to ensure that it is already fully charged before MOSFET Q9 turns on.
[0150]Another example implementation of the circuitry 1210 converts an AC voltage (e.g., from a building mains electrical supply) to a DC voltage suitable for providing power to an LED light source) and facilitates appreciable dimming of light output via 0-10V dimming. As would be readily appreciated in the art, 0-10V dimming is a lighting control method that produces varying light level outputs based on a direct current (DC) control voltage between 0 and 10 Volts. Accordingly, in these example implementations, both an AC voltage (to provide power to an LED light source) and a DC voltage (to provide dimming control of the LED light source) are provided as inputs to the circuitry 1210.
[0151]FIGS. 18A and 18B show respective portions of example circuitry 1210B that provides dimming. In particular, FIG. 18A illustrates a power portion 1210B-1 of the circuitry 1210B and FIG. 18B illustrates a control portion 1210B-2 of the circuitry. As shown in FIG. 18A, the power portion 1210B-1 receives an AC voltage input 1211 and employs a constant voltage flyback converter 1213 on a primary side and a constant current buck converter 1215 on the secondary side to convert the AC voltage to a DC voltage and provide a constant current LED output 1217. An integrated circuit in the constant current buck converter in the secondary side receives a control signal VT 1212 (also referred to herein as the “DC control signal 1212”) to controllably vary a value of the constant current LED output 1217, thereby varying the light output of the LED light source. As shown in FIG. 18B, the control portion 1210B-2 of the circuitry 1210B receives a 0-10V DC control input 1219 and employs a microcontroller 1221 to provide the control signal VT 1212 (which is in turn applied to the integrated circuit in the constant current buck converter of FIG. 18A) based on the 0-10V DC control input 1219. Thus, the circuitry 1210B according to this example is coupled to four input wires, e.g., two wires to provide the AC voltage input 1211 and two wires to provide the 0-10V DC control input 1219.
[0152]In yet other examples, the circuitry 1210 may be configured to adjust the light output (e.g., intensity) as well as correlated color temperature (CCT) of the light output. For circuitry configured for CCT control, in inventive aspects one or both of the AC half cycles of input AC voltage are employed to enable a phase dimmer to convey desired CCT in one half cycle and desired intensity in the other half cycle. In one example, the information is conveyed by varying the time that the phase cut dimmer conducts during the positive and negative half cycles. A controller of the driver circuitry decodes the incoming AC phase-cut waveform and converts it to two distinct signals representing intensity and CCT. Detailed examples of circuitry 1210 for CCT control are provided in U.S. Provisional Application No. 63/224,469, filed Jul. 22, 2021, entitled “METHODS AND APPARATUS FOR ENCODING ONE OR MORE HALF-CYCLES OF AN AC WAVEFORM TO CONTROL A LIGHTING FIXTURE,” which is hereby incorporated herein by reference.
[0153]The circuitry 1210 may generally include a printed circuit board (PCB) supporting the various circuit elements described above. As shown in FIGS. 2A and 2B, the PCB may be shaped as a donut (i.e., a circular PCB with an opening 1214 at its center). The opening 1214 may be shaped and/or dimensioned to receive an island section 1240 of the driver housing 1230 as will be discussed in more detail below. The opening 1214 may also allow passage of other components, such as an integrated power connector for the driver circuitry 1210, the electrical cables 1020, 1030a, 1030b, and/or the ground cables 1010 and 1014. It should be appreciated, however, the PCB of the circuitry 1210 is not limited to a donut-shape, but may have other shapes including, but not limited to, a solid circle (e.g., a circular shape with no center opening) and a semi-circle (e.g., a crescent).
[0154]The circuitry 1210 may be disposed within a cavity 1231 defined by the driver housing 1230 such that a sidewall 1232 and a base 1234 of the driver housing 1230 at least partially surrounds and encloses the circuitry 1210. When the driver module 1200 is mounted to the heat sink 1100, the driver circuitry 1210 may also be disposed entirely within the cavity 1104. In some implementations, the PCB may further include a keyed feature 1216 to align the circuitry 1210 to a corresponding keyed feature 1248 of the driver housing 1230 for assembly. The keyed features 1216 and 1248 may also constrain the movement of the circuitry 1210 within the driver housing 1230 to reduce or, in some instances, prevent unwanted physical contact between the electrical components of the circuitry 1210 and/or portions of the lighting module 1000a where the risk of short circuiting may be high, such as portions of the heat sink 1100 where bare metal may be exposed or portions of the circuit elements in the circuitry 1210 where the metal leads are exposed.
[0155]In some implementations, the taller circuit elements of the circuitry 1210 may also be disposed near the outer edge of the PCB where the cavity 1104 of the heat sink 1100 is larger. In this manner, the driver circuitry 1210 may be positioned closer to the partition 1120 of the heat sink 1100, thus reducing the exterior height hext of the lighting module 1000a. It should appreciated that, in some implementations, the various circuit elements of the circuitry 1210 may be placed at any location on the PCB, particularly if the exterior height hext of the lighting module 1000a is larger such that the taller circuit elements do not contact or interfere with the partition 1120. The light module 1000a may also generally support different driver circuitry so long as the circuitry fits within the size constraints (e.g., the diameter, the height) imposed by the driver housing 1230 and/or the heat sink 1100. For example, the lighting module 1000a may include a driver module 1200 with circuitry based on the TRIAC dimmer of FIGS. 17A and 17B or the 0-10V dimmer of FIGS. 18A and 18B.
[0156]In some implementations, a potting material 1202 may be added into the driver housing 1230 to encapsulate and/or seal at least a portion of the circuitry 1210. The potting material 1202 may also seal portions of the electrical wires coupled to the circuitry (e.g., the electrical cables 1020, 1030a, 1030, the ground cable 1014). The potting material 1202 may provide an electrically insulating medium to electrically insulate the circuitry 1210 from other components in the lighting module 1000a, such as the driver housing 1230 and the heat sink 1100. The potting material 1202 may conformally coat the circuitry 1210. For example, the potting material 1202 may be applied as a liquid, which forms a solid when cured. The potting material 1202 may be formed from various materials including, but not limited to a thermosetting polymer, a silicone rubber, and epoxy resins.
[0157]In some implementations, the driver module 1200 may further include a driver insulator 1250 disposed on the surface of the partition 1120 adjoining the cavity 1104 to provide an electrically insulating barrier between the exposed portions of the circuitry 1210 and the partition 1120 of the heat sink 1100. Said in another way, the driver insulator 1250 may cover the opening into the driver cavity 1231 so that the driver housing 1230 and the driver insulator 1250 together encapsulate the circuitry 1210 within the cavity 1104 of the heat sink 1100. It should be appreciated, however, that in implementations where the gap between the circuitry 1210 and the partition 1120 is sufficiently large such that the risk of electrical contact between the circuitry 1210 and the heat sink 1100 is low, the lighting module 1000a may not include the driver insulator 1250.
[0158]In some implementations, the driver housing 1230 and the driver insulator 1250 may not be directly coupled together. For example, FIGS. 1H, 1K, and 1L show the driver insulator 1250 may be inserted into the cavity 1104 of the heat sink 1100 first followed by the driver housing 1230 with the circuitry 1210 disposed within the cavity 1231. As shown, the driver housing 1230 may include snap-fit connectors 1236 that couple to the snap-fit receivers 1126 of the heat sink 1100. In some implementations, the driver insulator 1250 may not be held in place, but instead may float within the driver module 1200 so long as the driver insulator 1250 provides an insulating barrier between the circuitry 1210 and the heat sink 1100. In some implementations, the driver circuitry 1210 may not physically contact the driver insulator 1250. It should be appreciated, however, that in other implementations, the driver housing 1230 and the driver insulator 1250 may be coupled via various connecting mechanisms including, but not limited to, snap-fit connectors, a fastener, and an adhesive.
[0159]In some implementations, the lighting module 1000a may also include a ground connection. Unlike previous lighting modules, a ground connection may be provided directly between the circuitry 1210 and an external ground (e.g., the housing of a lighting system). This may be accomplished, for example, by utilizing a ground cable 1014 to electrically couple the circuitry 1210 to the heat sink 1100 and a ground cable 1010 to electrically couple the heat sink 1100 to the external ground.
[0160]As shown in FIGS. 1K, 1L, 2A, and 2B, one end of the ground cable 1014 may be electrically coupled to the PCB of the circuitry 1210. The ground cable 1014 may include a connector 1016 (e.g., a ring connector) at the other end to receive a fastener 1204 that couples the ground cable 1014 to the partition 1120 of the heat sink 1100 via an opening 1122. The ground cable 1010 may also include a connector 1012 (e.g., a ring connector) that overlaps the connector 1016 so that the fastener 1204 may also couple the ground cable 1010 to the heat sink 1100. It should be appreciated, however, that in other implementations, the ground cable 1010 and the connector 1012 may be coupled to another portion of the heat sink 1100 separate from the ground cable 1014. Once connected, the ground cable 1010 may then be routed through an opening 1246 on the driver housing 1230, together with the electrical cable 1020, for connection to the external ground. It should be appreciated, however, that in other implementations, the ground cable 1010 may be routed through a separate opening on the driver housing 1230.
[0161]The lighting module 1000a may also provide electrical cables 1020 to supply electrical power and/or a control signal to the driver module 1200 from an external power source and/or dimmer and the electrical cables 1030a and 1030b to supply electrical power to the light source 1300 from the driver module 1200. During assembly, the electrical cables 1030a and 1030b, which are connected directly to the circuitry 1210, may be routed through respective openings 1134 in the partition 1120 of the heat sink 1100 for connection to the light source holder 1400a. In some implementations, the light source holder 1400a may include poke-in connectors (not shown), which are configured to electrically contact the respective terminals of the light source 1300 when the light source 1300 is coupled to the light source holder 1400a. The electrical cables 1030a and 1030b may each be inserted into a respective poke-in connector and subsequently restrained. In other words, the electrical cables 1030a and 1030b may be electrically coupled to the light source 1300 via the light source holder 1400a without any soldering.
[0162]FIGS. 1H, 1L, and 2A show the electrical cable 1020 may be electrically coupled to the circuitry 1210 at one end and routed through the opening 1246 together with the ground cable 1010. At the other end, the electrical cable 1020 may include an electrical connector 1022 as shown in FIG. 1A. The electrical connector 1022 may be coupled to an electrical cable 1024 supplying the electrical power via a corresponding connector 1026 as shown in FIGS. 2C and 2D. In some implementations, the electrical connectors 1022 and 1026 may be interlocking and/or keyed connectors. In some implementations, the electrical connector 1022 may be integrated into the driver housing 1230 such that the electrical cable 1024 is coupled directly to the driver module 1200.
[0163]FIGS. 3A-3F show several additional views of the driver housing 1230. As shown, the driver housing 1230 may include the sidewall 1232 and the base 1234 (also referred to herein as the “driver base 1234”) that together define the cavity 1231 to contain the circuitry 1210 and, optionally, the potting material 1202. In some implementations, the sidewall 1232 and/or the base 1234 may have various cross-sectional shapes including, but not limited to a circle, an ellipse, a polygon, and any combinations of the foregoing.
[0164]In some implementations, the shape and/or dimensions of the base 1234 may be tailored to substantially enclose the cavity 1104 as shown in FIGS. 1A, 1B, 1H, and 1I. The sidewall 1232 may be shaped to conform with the sidewall 1110 of the heat sink 1100. For example, FIGS. 1H and 1I show the sidewall 1110 of the heat sink 1100 and the sidewall 1232 of the driver housing 1230 may be tapered. The draft angle of the sidewalls 1110 and 1232 may be tailored such that the driver housing 1230 is positioned in close contact with the heat sink 1100 to increase thermal dissipation from the circuitry 1210 and/or to secure/position the driver housing 1230 inside the cavity 1104. In some implementations, the sidewall 1232 may contact a ledge 1118, which functions as a mechanical stop limiting the extent the driver housing 1230 is inserted into the cavity 1104. In some implementations, the base 1234 may be substantially flush or flush with the opening of the cavity 1104 (i.e., the exterior surface of the base 1234 and the bottom end of the sidewall 1110 of the heat sink 1100 defining the opening into the cavity 1104 may lie on the same horizontal plane).
[0165]As shown in FIG. 3A, the driver housing 1230 may include one or more snap-fit connectors 1236 disposed along the exterior surface of the sidewall 1232 to engage the snap-fit receivers 1126 of the heat sink 1100, thus coupling the driver housing 1230 to the heat sink 1100. The snap-fit connectors 1236 may be disposed proximate to an opening defined by the sidewall 1232. In some implementations, the driver housing 1230 may include one or more pairs of snap-fit connectors 1236 disposed diametrically opposite to one another along the sidewall 1232. The driver housing 1230 may also include a keyed feature 1238 spanning the height of the sidewall 1232 that aligns with the keyed feature 1116 of the heat sink 1100. The keyed features 1238 and 1118 ensure the driver housing 1230 and, in particular, the circuitry 1210 are properly aligned to the heat sink 1100.
[0166]FIG. 3A further shows the base 1234 may include an island section 1240 disposed within the cavity 1231. As shown, the island section 1240 may include a sidewall 1242 that extends from the base 1234 towards the opening of the driver housing 1230. Thus, the sidewall 1242 may form a structure that is inserted through the opening 1214 of the circuitry 1210. In some implementations, the sidewall 1242 may mechanically constrain the lateral movement of the circuitry 1210 once inserted into the cavity 1231. In some implementations, the sidewall 1242 may be concentrically aligned with the sidewall 1232. The sidewall 1242 may also have various cross-sectional shapes including, but not limited to, a circle, an ellipse, a polygon, and any combinations of the foregoing.
[0167]The island section 1240 may also include a keyed feature 1248 extending from the sidewall 1242 along the base 1234, which aligns with the keyed feature 1216 of the circuitry 1210. The sidewall 1242 may further include one or more posts 1244 that extend from the exposed end of the sidewall 1242. The posts 1244 may abut the recessed section 1130 of the partition 1120, as shown in FIGS. 1H and 1I, to mechanically support the center portion of the driver module 1200. In other words, the posts 1244 may reduce or, in some instances, prevent the center portion of the module 1200 from being pushed into the cavity 1104 due to compliance in the driver housing 1230.
[0168]The posts 1244 may also provide openings to route the electrical wires (e.g., the electrical cable 1020, the ground cable 1010) from the circuitry 1210 and/or the heat sink 1100 into the island section 1240. The island section 1240, in turn, may include an opening 1246 disposed within the sidewall 1242 to provide a feedthrough for the electrical cable 1020 and/or the ground cable 1010 to be routed into/out of the driver housing 1230. The posts 1244 may additionally be shaped and/or dimensioned to have a contact area with the partition 1120 that is smaller than the sidewall 1242 in order to reduce unwanted heat conduction from the recessed section 1130 to the driver housing 1230. For example, the portion of the posts 1244 that contact the partition 1120 may be rounded and/or chamfered. The base 1234 may further include a label recess 1235 to receive label for the lighting module 1000a (e.g., a label identifying the various electrical and lighting specifications of the lighting module 1000a).
[0169]In some implementations, the driver housing 1230 may be formed from various electrically insulating materials including, but not limited to, polyvinyl chloride (PVC), acrylonitrile butadiene styrene (ABS), polycarbonate (PC), polyurethane (PU), polyethylene, polyethylene terephthalate, polypropylen