WO2023101805A1

WO2023101805A1 - Piezoelectric cooling device

Info

Publication number: WO2023101805A1
Application number: PCT/US2022/049806
Authority: WO
Inventors: Jiannan TAN; Sullivan DEE
Original assignee: Milwaukee Electric Tool Corporation
Priority date: 2021-12-01
Filing date: 2022-11-14
Publication date: 2023-06-08

Abstract

A cooling system is configured to reduce heat of functional components in a lighting apparatus that includes a housing. The cooling system includes a heatsink configured to be positioned in the housing and a piezoelectric fan configured to be positioned in the housing adjacent the heatsink. The heatsink is configured to absorb heat generated by one or more of the functional components. The piezoelectric fan includes an oscillating airfoil operable to move air across the heatsink and thereby dissipate heat absorbed by the heatsink. A temperature within the housing is decreased during oscillation of the oscillating airfoil.

Description

PIEZOELECTRIC COOLING DEVICE

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to co-pending U.S. Provisional Patent Application No. 63/284,863, filed December 1, 2021, the entire contents of which are incorporated herein by reference.

FIELD

[0002] The present disclosure relates to component cooling devices. More particularly, the present disclosure relates to piezoelectric devices for cooling electrical components (e.g., LED, PCBA, etc.) and heatsinks used therewith.

BACKGROUND

[0003] Typical component cooling devices, such as rotatable fans, often include multiple fan blades rotatable to generate a cooling airflow. These cooling devices may be positioned in electrical systems, such as lighting systems, power tools, and the like, to reduce the possibility of overheating of those system. Such fans may include a housing that conceals the fan blades and supports one or more grilles, shrouds, and the like. In these applications, such fans may be energized to push cooling air across a heatsink to dissipate heat generated by one or more electrical components within the system, such as an LED, a PCBA, a charging unit, or the like. The arrangement and number of fan blades or strips are a factor in durability, cost, cooling rate, and weight of the component cooling devices within the system.

SUMMARY

[0004] In one embodiment, the invention provides a cooling system configured to reduce heat of functional components in a lighting apparatus that includes a housing. The cooling system includes a heatsink configured to be positioned in the housing and a piezoelectric fan configured to be positioned in the housing adjacent the heatsink. The heatsink is configured to absorb heat generated by one or more of the functional components. The piezoelectric fan includes an oscillating airfoil operable to move air across the heatsink and thereby dissipate heat absorbed by the heatsink. A temperature within the housing is decreased during oscillation of the oscillating airfoil. [0005] In another embodiment, the invention provides a lighting apparatus including a housing, a heatsink positioned within the housing, a functional component mounted to the heatsink, and a piezoelectric fan positioned within the housing adjacent the heat sink. The piezoelectric fan includes an oscillating airfoil. The heatsink is configured to absorb heat generated by the functional component. The piezoelectric fan is operable to cool the heatsink.

[0006] In another embodiment, the invention provides a lighting apparatus including a body, a battery pack supported by the body, and a light head assembly supported by the body and electrically coupled to the battery pack. The light head assembly includes a heatsink, an LED mounted to the heatsink, and a piezoelectric fan positioned adjacent the heatsink. The piezoelectric fan includes an oscillating airfoil operable to cool the heatsink.

[0007] Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] FIG. 1 is a perspective view of a lighting apparatus, according to one embodiment of the disclosure.

[0009] FIG. 2 is a perspective view of a lighting apparatus, according to another embodiment of the disclosure.

[0010] FIG. 3 is a perspective view of a lighting apparatus, according to another embodiment of the disclosure.

[0011] FIG. 4A is a top view of a component cooling device useable with the lighting apparatuses of FIGS. 1-3.

[0012] FIG. 4B is a front view of the component cooling device.

[0013] FIG. 4C is a side view of the component cooling device, illustrating an airflow generated the component cooling device.

[0014] FIG. 4D is an isometric view of the component cooling device.

[0015] FIG. 5 is a perspective view of the component cooling device of FIGS. 4A-4D arranged to cool a light emitter and a light emitter housing useable with the lighting apparatuses of FIGS. 1-3, according to one example application [0016] FIG. 6 is a circuit diagram of the lighting apparatuses of FIGS. 1-3.

[0017] FIG. 7 is a partially exploded view of a light head having a light emitter and a light emitter housing useable with the lighting apparatuses of FIGS. 1-3, according to another example application, arranged with the component cooling device of FIGS. 4A-4D.

[0018] FIG. 8 is a perspective view of a light emitter and a heat sink useable with the lighting apparatuses of FIGS. 1-3, according to another example application, arranged with the component cooling device of FIGS. 4A-4D.

[0019] FIG. 9 is a perspective view of an alternative light head for use with the lighting apparatuses of FIGS. 1-3, the alternative light head including light emitter modules pivoted into an upward facing position.

[0020] FIG. 10 is a perspective view of the light head of FIG. 9, illustrating the light emitter modules pivoted into a downward facing position and an example position of the component cooling device within a housing of one of the light emitter modules.

[0021] FIG. 11 is a perspective view of a charger unit with the component cooling device of FIGS. 4A-4D, the charging unit useable with the portable lighting apparatuses of the FIGS. 1-3.

DETAILED DESCRIPTION

[0022] Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways.

[0023] It should be understood that although certain drawings illustrate hardware and software located within particular devices, these depictions are for illustrative purposes only. Functionality described herein as being performed by one component may be performed by multiple components in a distributed manner. Likewise, functionality performed by multiple components may be consolidated and performed by a single component. In some embodiments, the illustrated components may be combined or divided into separate software, firmware and/or hardware. For example, instead of being located within and performed by a single electronic processor, logic and processing may be distributed among multiple electronic processors. Regardless of how they are combined or divided, hardware and software components may be located on the same computing device or may be distributed among different computing devices connected by one or more networks or other suitable communication links. Similarly, a component described as performing particular functionality may also perform additional functionality not described herein. For example, a device or structure that is “configured” in a certain way is configured in at least that way but may also be configured in ways that are not explicitly listed.

[0024] FIGS. 1-3 illustrate embodiments of lighting apparatuses 10A, 10B, 10C for illuminating a jobsite, such as a construction site, or other large area. Each of the lighting apparatuses 10A, 10B, 10C may also be referred to as “site lights” or “stand lights.”

[0025] Each of the lighting apparatuses 10A, 10B, IOC includes a body 14, a telescopic arm assembly 18 supported by the body 14, and a light head assembly 22 coupled to the telescopic arm assembly 18 and movable relative to the body 14. The portable lighting apparatuses 10A, 10B, 10C also each include a power system 26 configured to provide electrical power to the light head assembly 22 and a cooling system 70 (FIGS. 4A-5) configured to regulate a temperature of components of the portable lighting apparatuses 10A, 10B, 10C (e.g., power system 26, light head assembly 22, etc.). The lighting apparatuses

IOA, 10B of FIGS. 1 and 2 can be like the mobile site lights discussed in U.S. Patent No. 10,851,976, the entire of contents of which are incorporated herein by reference. The lighting apparatus IOC of FIG. 3 can be like the portable stand lights discussed in U.S. Patent No. 10,378,739, the entire of contents of which are also incorporated herein by reference.

[0026] As further illustrated in FIGS. 1-3, the body 14 of each lighting apparatus 10 A,

IOB, IOC includes a base 46 having a plurality of channels 50 and a handle 54. The channels 50 and the handle 54 are both coupled to the base 46. The base 46 also includes a housing 58 that partially defines a housing volume 62 therein. As shown in FIGS. 1-3, the body 14 also includes one or more adjustable leg assemblies 64 coupled thereto and configured to provide additional stability and support for the body 14 during use. The body 14 and telescopic arm assembly 18 also define an axis 66 extending therethrough. In operation, the body 14 of the lighting apparatuses 10A, 10B, 10C is generally placed in an “upright orientation” whereby the axis 66 is maintained in a substantially vertical orientation.

[0027] The telescopic arm assembly 18 is supported by the body 14 and is moveable to an extended position, as shown in FIGS. 1-3, in which the light head assembly 22 is extended above the body 14 for an increased lighting area. Each lighting apparatus 10A, 10B, IOC is also collapsible to atransporting/storage/collapsed position in which the telescopic arm assembly 18 is retracted or shortened and the light head assembly 22 is proximate the body 14.

[0028] Referring now to FIGS. 4A-5, the light head assembly 22 of each lighting apparatus 10A, 10B, 10C includes a cooling system 70 configured to reduce heat of functional components in the lighting apparatuses 10A, 10B, IOC. The light head assembly 22 of each lighting apparatus 10A, 10B, IOC further includes a housing 74 and a light emitter 78 at least partially positioned/supported in the housing 74. In the illustrated embodiments, the light emitter 78 includes a plurality of light emitting diodes (LEDs). In other embodiments, the light emitter 78 may include a single LED or other suitable light-emitting component. The LEDs are powered by a battery pack 82 (FIG. 3) and linked by one or more printed circuit board assemblies (PCBAs). The LEDs, PCBAs, batteries, and other powered components (e.g., electrical components) may all generate heat during operation. The heat generated by such components may radiate and/or conduct into the housing(s) in which they are supported.

[0029] Referring to FIG. 3, the battery pack 82 may be a power tool battery pack 82 generally used to power a power tool, such as a lighting apparatus, an electric drill, an electric saw, and the like. For example, the battery pack 82 may be an 18-volt rechargeable battery pack, or an Ml 8 REDLITHIUM battery pack sold by Milwaukee Electric Tool Corporation. The battery pack 82 may include lithium ion (Li-ion) cells. In some embodiments, the battery packs may be of a different chemistry (e.g., nickel-cadmium (NiCa or NiCad), nickelhydride, and the like). In some embodiments, the battery pack 82 is an 18-volt battery pack. In other embodiments, the voltage of the battery pack may vary (e.g., the battery pack may be a 4-volt battery pack, a 28-volt battery pack, a 40-volt battery pack, or battery pack of any other voltage). The battery pack 82 may further include an indicator to display the current state of charge of the battery pack 82 and/or other characteristics of the battery pack 82. The illustrated lighting apparatuses 10A, 10B, 10C may be operated with one or more battery packs of different voltages up to approximately 84-volts. The illustrated lighting apparatuses 10A, 10B, 10C can also include one or more AC power outlets and an AC power inlet (e.g., power system 26) to allow the lighting apparatuses 10A, 10B, IOC to be powered by an AC power source 84. [0030] With continued reference to FIGS. 4A-5, the cooling system 70 includes a heatsink 86 positioned in the housing 74. In some embodiments, the heatsink 86 is integrally formed with the housing 74. In other embodiments, the heatsink 86 may be a separate piece from the housing 74. The heatsink 86 is generally made of metal, such as aluminum. The heatsink 86 may include features (e.g., fins) to increase a surface area of the heatsink 86. As stated above, components in the light head assembly 22, such as the LEDs, generate heat during operation. The heatsink 86 is supported by the housing 74 within a volume 90 of the housing 74 to absorb the heat generated by the LEDs, PCBAs, and the like. The volume 90 may also be considered an electrical volume 90. The generated heat may be transferred to the heatsink 86 via conduction and/or radiation.

[0031] The heat generated by the LEDs and absorbed by the heatsink 86 radiates into the volume 90 of the housing 74. In a typical light head assembly, the heat within the housing volume may be exhausted from the housing via natural convection driven by atmospheric pressure/temperature differences between the housing volume and an ambient surrounding. In the illustrated embodiment, the heat within the housing volume 90 may be exhausted from the housing 74 to the ambient surrounding via forced convection driven by the cooling system 70. A temperature within the housing 74/volume 90, relative natural convection in a typical housing, is decreased at a higher rate via the forced convection driven by the cooling system 70. In the illustrated embodiment, the heatsink 86 is positioned in the housing volume 90 between a housing inlet 94 and a housing outlet 96, with a heat generating component (e.g., LED) positioned therebetween. In other words, the cooling system 70 is positioned adjacent the heat generating components to force air through the volume 90, across the heatsink 86, from the inlet 94 to the outlet 96.

[0032] With continued reference to FIGS. 4A-5, the cooling system 70 includes a piezoelectric fan 72 that generates airflow by vibrating cantilevers instead of spinning blades. In the illustrated embodiment, the piezoelectric fan 72 includes one or more oscillating airfoils/vibrating cantilevers 100 operable to move air through the housing 74 and the electrical volume 90, which thereby dissipates heat absorbed and radiated by the heatsink 86. The airfoil 100 may be a tab, blade, fan, or the like that functions as a piezoelectric transducer. In the illustrated embodiment, the piezoelectric fan 72 includes two airfoils 100. In other embodiments, the piezoelectric fan 72 may include fewer or more airfoils 100. For example, the piezoelectric fan 72 may include a single airfoil or three or more airfoils. In a piezoelectric system, the piezoelectric transducer (e.g., the airfoil 100) is the prime mover of a piezoelectric fan.

[0033] Compared to an airflow profile of a rotary fan that may have a dead point in a central region of the rotary fan, the illustrated piezoelectric fan 72 produces a uniform airflow profile that generates less noise than that of rotary fan. When electric power, such as an AC voltage at 60 Hz is applied, the electric power causes the piezoelectric transducer to flex back and forth, also at 60 Hz. In a direct current (DC) application, such as in the battery-operated system of the illustrated embodiment, an inverter circuit is employed to produce an AC output. The inverter circuit may include an inverter 76 provided on a PCBA.

[0034] FIG. 6 illustrates a circuit diagram of the lighting apparatuses 10A, 10B, 10C. The lighting apparatuses 10A, 10B, 10C are capable of being powered by the battery pack 82 or the AC power source 84. When powered by the battery pack 82, the light emitter 78 receives the DC output from the battery pack 82, and the inverter 76 produces the AC output to power the piezoelectric fan 72. When powered by the AC power source 84, the piezoelectric fan 72 receives the AC output from the AC power source 84, and a rectifier 88 produces a DC output to power the light emitter 78. If the battery pack 82 and the AC power source 84 are connected to the lighting apparatus 10A, 10B, 10C, the battery pack 82 may be charged by the AC power source 84, as a controller 92 routes the AC output through a charging circuit 98 to the battery pack 82. The controller 92, or processor, may be implemented as a microprocessor with separate memory. In other embodiments, the controller 92 may be implemented as a microcontroller with memory on the same chip. In other embodiments, the controller 92 may be implemented partially or entirely as, for example, a field-programmable gate array (FPGA), an application specific integrated circuit (ASIC), and the like, and the memory may not be needed or may be modified accordingly. The memory may include non-transitory, computer-readable memory that stores instructions that are received and executed by the controller 92 to carry out functionality of the lighting apparatuses 10A, 10B, 10C.

[0035] During operation of the piezoelectric fan 72, the airfoils 100 may be tuned to oscillate at a resonating frequency with the electrical input frequency. Such resonance minimizes a power consumption of the piezoelectric fan 72 without sacrificing an oscillating range of the airfoils. More specifically, oscillation of the airfoils 100 may be tuned to resonate at a desired frequency by adjusting a length, thickness, and/or material of the airfoil 100. As illustrated in FIG. 4B, the airfoils 100 are moveably supported within a housing 104 of the piezoelectric fan 72 at opposing end. Each of the opposing ends of the airfoils 100 are coupled to a living hinge 108 that is flexibly attached to the housing 104. The opposing ends also include electrodes 112 connected to a surface of the airfoil 100. The electrodes 112 transmit the electrical power and desired frequency to the airfoils 100 to cause the airfoils 100 to bend/deflect/actuate at the desired resonating frequency. In some embodiments, the airfoils 100 are made of a thin, pliable sheet, such as Mylar, Melinex, Hostaphan, Skyroll, or another type of polyester film. In other embodiments, the airfoils 100 are made of a thin pliable metal. In other embodiments, the piezoelectric fan 72 may have other configurations.

[0036] In one example application of the piezoelectric fan 72, as illustrated in FIG. 5, the airfoils 100 are oriented to direct cooling airflow through the electrical volume 90, which may be defined by the housing 74 being generally U-shaped. The heatsink 86 may be positioned and/or formed in the housing 74 along an elongated direction of the housing 74 such that cooling air flows through an elongated part of the U-shaped housing 74 to contact elongated surfaces of the heatsink 86.

[0037] The housing 74 has a first temperature within the volume 90 when the LED is not being operated and the airfoils 100 are still (e.g., airfoils not oscillating). As the LED is operated, the temperature in the volume 90 will increase to a second temperature. The airfoils 100 may then be oscillated to move air across the heatsink 86 to reduce the temperature in the volume 90 below the second temperature. In a theoretical embodiment, the second temperature can be reduced when the airfoils 100 are still if an amount of material by weight of the heatsink 86 is increased. In such a theoretical embodiment, in order to generally match the cooling capability/desired temperature provided by the piezoelectric fan 72, the amount of material by weight of the heatsink 86 would be doubled. In other words, inclusion of the piezoelectric fan 72 of the illustrated embodiment allows for the amount of material by weight of the heatsink 86 to be reduced by approximately 50%. In other embodiments, inclusion of the piezoelectric fan 72 allows for greater reduction in the amount of material by weight of the heatsink 86. In some embodiments, inclusion of the piezoelectric fan 72 results in a volume temperature that is approximately 8 degrees Celsius less than the theoretical embodiments discuss herein. Thus, inclusion of the piezoelectric fan 72 allows an overall weight of the light head assembly 22, and ultimately the portable lighting apparatuses 10 A, 10B, 10C, to be reduced while maintaining a desired cooling capability. In some embodiments, inclusion of the piezoelectric fan 72 reduces the weight of the respective portable lighting apparatuses 10A, 10B, 10C by approximately one pound. Compared to one theoretical embodiment that utilizes a rotary CPU-type fan (e.g., computer fan), inclusion of the piezoelectric fan 72 results in the respective portable lighting apparatuses 10A, 10B, 10C having a weight approximately 44% lighter than if a rotary CPU- type fan was used.

[0038] FIG. 7 illustrates a light head assembly 222 that is substantially similar to the light head assembly 22 described above with reference to FIGS. 1-5. Like the light head assembly 22, the light head assembly 222 is useable with the portable lighting apparatuses 10A, 10B, IOC of FIGS. 1-3. Features of the light head assembly 222 are identified with relation to the light head assembly 22 with reference numbers plus “200.”

[0039] For instance, the light head assembly 222 of FIG. 7 includes a plurality of LEDs 278 powered by one or more batteries and linked by a PCBA. The LEDs 278 are mounted to a heatsink 286 that is supported in a light head housing 274. A piezoelectric cooling fan 272 is also supported by the housing 274 adjacent the heatsink 286 to move air across surfaces of the heatsink 286. The housing 274 further includes inlet vents 294 through which the piezoelectric fan 272 draws air into an electrical volume 290 from outside of the volume 290. The piezoelectric fan 272 forces the air across the heatsink 286 and through an outlet or exhaust vent 296. A direction the air travels could be reversed by altering the orientation and/or geometry of the piezoelectric fan 272.

[0040] A temperature of the air going into the volume 290 generally matches a temperature of the ambient surroundings, and a temperature of the air going out of the volume 290 is generally heated up beyond that of the ambient surrounding due to the heat generated by the LEDs 278 and any other electrical components (e.g., PCBA, wiring, etc.). As illustrated in FIG. 1, the portable lighting apparatuses 10A, 10B, 10C can support up to four light head assemblies 222 coupled to the telescopic arm assembly 18.

[0041] FIG. 8 illustrates a light head assembly 322 that is substantially similar to the light head assembly 22 described above with reference to FIGS. 1-5. Like the light head assembly 22, the light head assembly 322 is useable with the portable lighting apparatuses 10A, 10B, 10C of FIGS. 1-3. Features of the light head assembly 322 are identified with relation to the light head assembly 22 with reference numbers plus “300.”

[0042] For instance, the light head assembly 322 of FIG. 8 includes a cooling system 370 and a plurality of LEDs 378 powered by one or more batteries and linked by a PCBA. The LEDs 378 are mounted to a heatsink 386 that may be directly coupled to a light head housing 374. A piezoelectric cooling fan 372 is also positioned adjacent the heatsink 386 to move air across surfaces of the heatsink 386. In the illustrated light head assembly 322 of FIG. 8, the LEDs 378 may be integrally formed with the heatsink 386 or alternately coupled to the heatsink 386 via one or more fasteners. The light head assembly 322 may further include a screen or lens positioned over the LEDs 378.

[0043] FIGS. 9 and 10 illustrate a light head assembly 422 that is substantially similar to the light head assembly 22 described above with reference to FIGS. 1-5. Like the light head assembly 22, the light head assembly 422 is useable with the portable lighting apparatuses

IO A, 10B, 10C of FIGS. 1-3. Features of the light head assembly 422 are identified with relation to the light head assembly 22 with reference numbers plus “400.”

[0044] For instance, the light head assembly 422 of FIGS. 9 and 10 includes three independent light heads 424 each pivotally coupled to the telescopic arm assembly 18 relative a horizontal direction B through more than 180 degrees. Each of the independent light heads 424 is pivotable between a generally upward facing direction (FIG. 9) and a generally downward facing direction (FIG. 10) and may include a spring-loaded ratchet mechanism, or another mechanism, configured to releasably secure each of the light heads 424 independently in various, discrete positions about the horizontal direction B.

[0045] Each of the heads 424 further include a plurality of LEDs 478 powered by one or more batteries and linked by a PCBA. The LEDs 478 are mounted to a heatsink that is supported in a light head housing 474. A piezoelectric cooling fan 472 can be supported by the housing 474 adjacent the heatsink to move air across surfaces of the heatsink. The housing 474 further includes inlet vents 494 through which the piezoelectric fan 472 draws air into an electrical volume from outside of the volume. The piezoelectric fan 472 forces the air across the heatsink and through an outlet or exhaust vent 496.

[0046] A temperature of the air going into the volume generally matches a temperature of the ambient surroundings, and a temperature of the air going out of the volume is generally heated up beyond that of the ambient surrounding due to the heat generated by the LEDs 478 and any other electrical components (e.g., PCBA, wiring, etc.).

[0047] With reference to FIG. 11, one or more of the portable lighting apparatuses 10A,

IOB, 10C includes a charger unit 512 configured for recharging a battery (e.g., the battery packs 82). In some embodiments, the charger unit 512 is disposed within the base 46. The charger unit 512 includes a housing 516 defining an electrical volume 520 therein. The charger 512 also includes one or more electrical components 524 (e.g., resistors, capacitors, transistors, etc.) positioned within the electrical volume 520, and a cooling system 528 configured to cool the electrical components 524 in the electrical volume 520. In the illustrated embodiment, the electrical volume 520 of the charger 512 is fluidly isolated from the surrounding atmosphere.

[0048] The cooling system 528 of the charger 512 further includes a piezoelectric cooling fan 540, an outlet 544 adjacent the piezoelectric cooling fan 540, an inlet 548, and one or more heatsinks 552 supported partially within the electrical volume 520 and positioned between the outlet 544 and the inlet 548. The piezoelectric cooling fan 540 can be energized to pull air into the electrical volume 520 through the inlet 548, across the heatsinks 552, and out of the electrical volume 520 through the outlet 544. An area of surfaces of the heatsinks 552 provides maximum thermal communication with the air flowing though the electrical volume 520. In some embodiments, the housing 516 includes seals to isolate the airflow through the electrical volume 520 from the surround ambient air.

[0049] Although particular embodiments embodying independent aspects of the present invention have been shown and described, other alternative embodiments will become apparent to those skilled in the art and are within the intended scope of the independent aspects of the invention. For example, although the above piezoelectric fans have been described with reference to the lighting systems described herein, the applications of the disclosed piezoelectric fans are contemplated for other power tool and battery powered devices.

[0050] Various features and advantages of the invention are set forth in the following claims.

Claims

CLAIMS What is claimed is:

1. A cooling system configured to reduce heat of functional components in a lighting apparatus that includes a housing, the cooling system comprising: a heatsink configured to be positioned in the housing, the heatsink configured to absorb heat generated by one or more of the functional components; and a piezoelectric fan configured to be positioned in the housing adjacent the heatsink, the piezoelectric fan including an oscillating airfoil operable to move air across the heatsink and thereby dissipate heat absorbed by the heatsink; wherein a temperature within the housing is decreased during oscillation of the oscillating airfoil.

2. The cooling system of claim 1, further comprising: a second heatsink configured to absorb heat generated by another of the functional components; and a second piezoelectric fan positioned adjacent the second heatsink, the second piezoelectric fan including an oscillating airfoil operable to move air across the second heatsink and thereby dissipate heat absorbed by the second heatsink.

3. The cooling system of claim 2, wherein the first heatsink is positioned within a light head assembly of the lighting apparatus, and wherein the second heatsink is positioned within a body of the lighting apparatus.

4. The cooling system of claim 1, wherein the functional components include an LED, and wherein the heatsink is configured to support the LED.

5. The cooling system of claim 1, wherein the functional components include a charger unit, and wherein the heat sink is configured to be positioned adjacent the charger unit.

6. The cooling system of claim 1, wherein the piezoelectric fan is configured to direct air into the housing through an inlet vent, across the heatsink, and out of the housing through an outlet vent.

7. The cooling system of claim 1, wherein the piezoelectric fan includes two or more oscillating airfoils.

8. The cooling system of claim 1, wherein the oscillating airfoil is made of a polyester film.

9. The cooling system of claim 1, wherein the oscillating airfoil is made of a thin pliable metal.

10. The cooling system of claim 1, wherein the lighting apparatus includes a power source providing an electrical input frequency, and wherein the oscillating airfoil oscillates at a resonating frequency with the electrical input frequency.

11. A lighting apparatus comprising: a housing; a heatsink positioned within the housing; a functional component mounted to the heatsink, wherein the heatsink is configured to absorb heat generated by the functional component; and a piezoelectric fan positioned within the housing adjacent the heat sink, the piezoelectric fan including an oscillating airfoil, the piezoelectric fan operable to cool the heatsink.

12. The lighting apparatus of claim 11, wherein the heatsink is a first heatsink, the functional component is a first functional component, and the piezoelectric fan is a first piezoelectric fan, and wherein the lighting apparatus further comprises: a second heatsink, a second functional component mounted to the second heatsink, wherein the second heatsink is configured to absorb heat generated by the second functional component, and a second piezoelectric fan positioned adjacent the second heatsink, the second piezoelectric fan including an oscillating airfoil, the second piezoelectric fan operable to cool the second heatsink.

13. The lighting apparatus of claim 12, further comprising a base and a light head assembly supported by the base, wherein the housing is part of the base, and wherein the second heatsink, the second functional component, and the second piezoelectric fan are positioned within the light head assembly.

14. The lighting apparatus of claim 11, further comprising a light head assembly, wherein the housing is part of the light head assembly.

15. The lighting apparatus of claim 14, wherein the functional component is an LED of the light head assembly.

16. The lighting apparatus of claim 14, further comprising a body and a telescopic arm supported by the body, wherein the light head assembly is coupled to the telescopic arm assembly and movable relative to the body.

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17. The lighting apparatus of claim 16, further comprising one or more adjustable leg assemblies coupled to the body and operable to support the body.

18. The lighting apparatus of claim 11, wherein the functional component is a charging circuit.

19. The lighting apparatus of claim 11, further comprising a battery pack electrically coupled to the functional component and the piezoelectric fan, wherein the battery pack is operable to power the functional component and the piezoelectric fan.

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20. A lighting apparatus comprising: a body; a batery pack supported by the body; and a light head assembly supported by the body and electrically coupled to the batery pack, the light head assembly including a heatsink, an LED mounted to the heatsink, and a piezoelectric fan positioned adjacent the heatsink, the piezoelectric fan including an oscillating airfoil operable to cool the heatsink.

21. The lighting apparatus of claim 20, wherein the light head assembly is one of a plurality of light head assemblies, each of the plurality of light head assemblies including a heat sink, an LED, and a piezoelectric fan.

22. The lighting apparatus of claim 20, further comprising a telescopic arm assembly supported by the body, wherein the light assembly is coupled to an end of the telescopic arm assembly.

23. The lighting apparatus of claim 22, wherein the light head assembly is pivotably coupled to the telescopic arm assembly.

24. The lighting apparatus of claim 20, further comprising one or more adjustable leg assemblies coupled to the body and operable to support the body.

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