Abstract:
Novel arrangements are disclosed that provide for replacement of printed circuit boards useful in regulating current for LEDs. In one embodiment, a conductive track is disclosed that forms a pattern for placement of electrical components. The track can be made out of any suitably conductive material and may be stamped, cut, or formed depending on the material type. The conductive track can conduct both electricity and heat. Portions of the conductive track can be removed creating a gap. Electrical components can be placed along the conductive track spanning the gap to create a circuit path. Other embodiments include wiring harnesses that contain embedded electrical components. The harnesses may occupy less space than some embodiments of the conductive track. An electrical connector may be provided to allow easy replacement of the LED.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention resides generally in the field of illumination, and in a particular aspect relates to systems useful in LED illumination.  
       BACKGROUND  
       [0002]     Light emitting diodes (LEDs) are becoming lighting devices of choice, useful in a range of applications, some of which include replacements for incandescent lamps. The popularity of LEDs in some fields is driven in part by the relatively long life of LEDs and the reduction in power required to produce light comparable to incandescent lighting systems. This reduction in power is particularly attractive in a number of different technological fields that look to reduce power consumption of larger electrical systems or alternatively utilize the excess for other electrical devices. As an example of one field that is increasingly turning to LED lighting systems, the automotive industry has begun exploring, and in some cases actually using LEDs as replacements for incandescent lamps.  
         [0003]     LEDs are made from semiconductor materials and have the property of producing light upon excitation by an electric current. In addition to producing light, LEDs also produce heat that if not properly dissipated may subject the LED to high operating temperatures. High operating temperatures reduce the efficiency of the LED to produce light and may also reduce the effective life of the LED. Generally speaking, higher current generates more light output and higher heat. At a point, the higher current levels will reduce the efficiency of the LED thus producing more heat and less light. Heat sinks can be used in some devices to extract heat from the LED thus lowering the operating temperature. The lower operating temperature, in turn, encourages a higher level of efficiency of the LED to produce light and possibly also preserves the effective life of the LED.  
         [0004]     Because LEDs may generate more heat as more light is driven at high current levels, LEDs are sometimes coupled to driving circuits to regulate the current to a desired level. The driving circuitry can be composed of many different types of electrical components and are often mounted on printed circuit boards (PCB).  
         [0005]     Printed circuit boards, unfortunately, can be the highest cost component in LED lamp assemblies. Furthermore, PCBs can occupy valuable space that could otherwise be used for other desirable purposes.  
         [0006]     Because of this, it can sometimes be difficult to lower the cost of an LED lamp to a point where it can be a viable replacement for incandescent lamps.  
         [0007]     In view of this background, the need remains for improved systems for LED lighting devices. The present invention is addressed to these needs.  
       SUMMARY  
       [0008]     Accordingly, in certain aspects, disclosed embodiments provide novel arrangements for illuminating mobile vehicles. The novel arrangements involve the use of light emitting diodes that rely on drive components that need not be mounted to a printed circuit board.  
         [0009]     Accordingly, in one aspect, certain embodiments provide an electrical circuit comprising a unsupported conductor having at least one gap formed therein and an electrical component having a first lead and a second lead, the first and second leads being conductively coupled to the unsupported conductor such that the electrical component bridges the gap.  
         [0010]     In another aspect, certain embodiments provide an electrical circuit comprising an unsupported conductor having a first portion and a second portion and at least one electrical component. Each of said at least one electrical components have a first lead and a second lead, the first lead being conductively coupled to the first portion and the second lead being conductively coupled to the second portion wherein the first portion and the second portion are coupled only by said at least one electrical component and wherein at least one electrical component forms a structural member of said unsupported conductor.  
         [0011]     In another aspect, certain embodiments provide a conductive device kit comprising at least one electrical component and an unsupported conductor, the unsupported conductor having at least a portion adapted to be removed thereby forming a gap. The unsupported conductor is configured to receive at least one electrical component across the gap thereby forming a circuit path.  
         [0012]     In a further aspect, certain embodiments provide a method of making a conductive device, the method comprising providing an operative piece, shaping the operative piece into an unsupported conductor, forming a gap in the unsupported conductor and placing an electrical component across the gap thereby forming a circuit path.  
         [0013]     In still another aspect, certain embodiments provide a method of making a conductive device, the method comprising providing an unsupported conductor, forming a gap, and placing an electrical component across the gap thereby forming a circuit path.  
         [0014]     In still another aspect, certain embodiments provide a method of retrofitting a lighting device, the method comprising providing a lamp assembly, removing an existing lighting source from the lamp assembly, providing an unsupported conductor having electrical components forming a circuit, and placing the unsupported conductor into the cradle.  
         [0015]     In still another aspect, certain embodiments provide a wiring assembly embedded with a circuit, the assembly comprising an unsupported conductor having a first wire section and a second wire section with a gap therebetween, an electrical component having a first component end and a second component end, the electrical component coupling the first and second wire sections across the gap, and a light emitting diode operatively coupled to the unsupported conductor.  
         [0016]     In another aspect, certain embodiments provide a wiring assembly embedded with a circuit, the assembly comprising an unsupported conductor having a first wire section and a second wire section with a gap therebetween, an electrical component having a first component end and a second component end, the electrical component coupling the first and second wire sections across the gap, a connector operatively coupled to the first end; and a light emitting diode selectively operatively coupled to the connector.  
         [0017]     The disclosed embodiments provide LED lighting systems that need not rely on printed circuit boards for useful placement of electrical drive components. Additional embodiments as well as features and advantages of the invention will be apparent from the further descriptions herein.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0018]     Although the characteristic features of this invention will be particularly pointed out in the claims, the invention itself, and the manner in which it may be made and used, may be better understood by referring to the following description taken in connection with the accompanying figures forming a part thereof.  
         [0019]      FIG. 1  is a perspective view of one embodiment of a carrier.  
         [0020]      FIG. 2  is a perspective view of one embodiment of a carrier with electronic components.  
         [0021]      FIG. 3  is a perspective view of the carrier with electronic components of  FIG. 2  after further processing.  
         [0022]      FIG. 4  is a perspective view of another embodiment of a carrier with electronic components.  
         [0023]      FIG. 5  is a perspective view of one embodiment of a lamp.  
         [0024]      FIG. 6  is a perspective view of another embodiment of a lamp.  
         [0025]      FIG. 7  is a perspective view of one embodiment of a lamp assembly.  
         [0026]      FIG. 8  is a perspective view of one embodiment of a lamp assembly.  
     
    
     DETAILED DESCRIPTION  
       [0027]     For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, and alterations and modifications in the illustrated devices, and further applications of the principles of the invention as illustrated therein are herein contemplated as would normally occur to one skilled in the art to which the invention relates.  
         [0028]     As described above, certain embodiments of the present invention provide novel arrangements for illuminating mobile vehicles. As used herein, the term “mobile vehicles” includes, but is not limited to, passenger cars, trucks, buses, tractors, trailers, heavy equipment, marine craft, aircraft, etc. Also as used herein, the term “light emitting diode,” or “LED,” refers to diodes that can be made of materials such as, but not limited to, GaAs, GaAlAs, GaAsP on a GaAs substrate, GaP, GaAlAsP, GaAsP on GaP substrate, InGaAlP, 2-chip yellow GaP, GaAlP, GaP, and InGaN. Also as used herein, the term “light” refers to electromagnetic radiation in general whether or not the radiation is at a wavelength visible to the human eye.  
         [0029]     By way of explanation only, a printed circuit board (PCB) can sometimes be thought of as composed of conductive tracks supported by a non-conductive board. The board provides, among other things, a platform for support of the conductive tracks. Some materials useful for the board are FR4 and CEM1. The conductive tracks found on PCBs can be superimposed on the board through a combination of lamination, etching, and/or electroplating processes, among others. The conductive tracks form the electrical connections required to communicate current between components. The embodiments of the present invention, however, eliminate the non-conductive board and instead rely solely on the conductive tracks for both electrical connectivity and structural support. In the embodiments of the present invention the above described tracks can be referred to as unsupported conductors. In some embodiments the unsupported conductors disclosed herein can be formed using methods other than lamination, etching and/or electroplating. For example, the unsupported conductors can be stamped, formed or cut. In other embodiments the unsupported conductors can be composed of wire leads between electrical components. Still other types of unsupported conductors are contemplated. The unsupported conductors can be made from any electrically conductive metal or alloy, where copper is but one example.  
         [0030]     It will be appreciated that many electrically conductive materials are also useful in conducting heat. It would be beneficial in some applications, therefore, to use unsupported conductors having larger dimensions than those typically found on PCBs such that the tracks consist of more material useful in conducting heat away from certain electrical components. By way of example only, in some embodiments the unsupported conductor could be made of copper for conducting electric current and also for conducting heat away from heat generating electrical components such as LEDs.  
         [0031]     Turning now to  FIG. 1 , unsupported conductor  10  is shown prior to installation of an LED and associated electrical components. Unsupported conductor  10  can be shaped, for example, by stamping, cutting, or forming conductive material. Unsupported conductor  10  can be formed in a general shape required for installation interior to a lighting system. In one embodiment, the outer dimensions, thickness, and elevation changes of unsupported conductor  10  can be formed to accommodate installation in a headlamp assembly for a mobile vehicle.  
         [0032]     Unsupported conductor  10  can have connectors  20  formed by snipping the metal frame and bending tabs  30  out of the plane of unsupported conductor  10 . Connectors  20  are formed to receive electrical components associated with the LED and in that regard can take on a variety of forms not shown in the embodiment of  FIG. 1 . For example, connectors  20  can be raised or bent in the direction shown in  FIG. 1  by crimping the edge of unsupported conductor  10  rather than snipping, or can be dimpled into unsupported conductor  10  thereby forming a mounded surface. It is also possible to form connectors  20  by depressing the metal of unsupported conductor  10  into shallows or dimples away from the direction shown in  FIG. 1 . Connectors  20  can also be configured to allow the electrical component to be snap fit to unsupported conductor  10  such as through a crimp tab. Unsupported conductor  10  can also be formed to contain holes through which the lead of an electrical component may pass. Alternatively, connectors  20  need not be present on some embodiments so long as sufficient space exists on unsupported conductor  10  to accommodate the electrical component sought to be mounted.  
         [0033]     Fences  40  can be formed in unsupported conductor  10  to constrain the movement of some electrical components such as an LED. In the pre-installed configuration shown in  FIG. 1 , tabs  50  can provide structural support to unsupported conductor  10 .  
         [0034]      FIG. 2  shows unsupported conductor  10  after installation of LED  60  and associated electrical components  70  and  80 . Though electrical components  70  and  80  are shown attached to connectors  20  that have been formed using the arrangement described previously, it will be understood that other connection methods can also be used as described above. Any leaded electronic components (resistors, diodes, etc.) can be secured to unsupported conductor  10  by, for example, resistance welding. Surface mount components such as LEDs, resistors, diodes, etc., can be secured using non-contact soldering techniques such as reflow, laser, or hot air. In the composition of unsupported conductor  10  and its configuration shown in  FIG. 2  it will be understood that the unsupported conductor should be further processed to remove or otherwise sever tabs  50  prior to use of the electrical device.  
         [0035]      FIG. 3  shows the configuration of unsupported conductor  10  populated with electrical devices and further processed from the embodiment disclosed in  FIG. 2 . Tabs  50  previously shown in  FIGS. 1 and 2  are shown in  FIG. 3  as severed and bent forming gaps  90  and bent pieces  100  and  110 . Tabs  50  have been severed in a manner described above so as to eliminate the conductive path through tabs  50  and instead provide a conductive path through electrical components  70  and  80 . Other techniques can be used to sever and bend tab  50 , such as a single stamping motion like crimping. The particular technique chosen for any individual application may depend on the tooling available. Gap  90  can be formed to prevent arcing between bent pieces  100  and  110  depending on operating conditions such as voltage levels and atmospheric conditions. The configuration shown in  FIG. 3  can be referred to as unsupported conductor  120 . Unsupported conductor  120  can conduct electricity through electrical components  70  and  80  thereby forming an electric circuit, and can also conduct heat away from LED  60  as described above. Other manufacturing techniques can be used to sever tabs  50  such as, but not limited to, cutting tabs  50  completely from carrier  10 .  
         [0036]      FIG. 4  shows another embodiment of an unsupported conductor populated with electrical components. Components  70  and  80  along with LED  60  are shown mounted to unsupported conductor  125 . Unsupported conductor  125  is similar in many respects to unsupported conductor  120  in  FIG. 3 , with the exception that the tabs have been removed completely as can be seen by gap  127 . Gap  127  can be created by snipping both ends of the tab, or alternatively can be created with a single stamping motion. Other methods can also be used to remove the tab.  
         [0037]     After tabs  50  have been removed from the unsupported conductor, circuit paths are formed between electrical components through segments  128   a ,  128   b ,  128   c ,  128   d ,  128   e  and  128   f  of the unsupported conductor. The segments serve as conduits for electrical communication between and among the electrical components and the power supply.  
         [0038]     An unsupported conductor as described above may be useful in many applications and can offer cost savings compared to printed circuit boards. The unsupported conductor can be manufactured cheaply by simply stamping a shape into stock metal sheet as compared to the relatively complex procedure of laminating, etching and/or electroplating required for some PCBs. The relative expense of producing the unsupported conductor may also lead to cost savings if replacement of the unsupported conductor becomes necessary.  
         [0039]     Because some applications contemplate using the unsupported conductor as described above as replacements for incandescent lamp bulbs, the unsupported conductor can be used as retrofit kits useful for manufacturers, retailers, mechanics, and consumers. Many other uses are contemplated for the unsupported conductor.  
         [0040]     Turning now to  FIG. 5 , lamp assembly  130  is depicted as composed of lens  140 , unsupported conductor  120 , cradle  150  and socket base  165 . In the illustrated embodiment, unsupported conductor  120  is configured to be received by cradle  150  in a manner reminiscent of U.S. patent application Ser. No. 10/920,796 to William Dominic Grote III titled “Conversion Cradle Incandescent Lamp to LED Lamp.” Cradle  150  can be configured to contain electrical components, circuit boards, or other accessories apart from unsupported conductor  120 . Cradle  150  is adapted to be received by socket base  165  such that it provides a platform to mount unsupported conductor  120  within the socket base. The design of the cradle shown in the embodiment of  FIG. 5  provides a mechanism through which an LED assembly can be used in an existing incandescent bulb lamp assembly. Sockets  165  are adapted to receive terminals formed in unsupported conductor  120 , thus providing power to light the LED. It will be understood, however, that lamp assembly  130  may not only be useful as a retrofit kit, but may also be originally designed for use with LED lighting systems.  
         [0041]      FIG. 6  depicts a housing  170  tooled to accommodate unsupported conductor  120  without the need for the cradle as depicted in  FIG. 5 . Dispensing with the need for a cradle may reduce the cost of manufacture which may be attractive to some businesses. The lamp system shown in  FIG. 6  can also be used as a retrofit to existing lamp systems whereby the entire lamp system is replaced as opposed to just the bulb as depicted in  FIG. 5 . Similar to the embodiment shown in  FIG. 5 , unsupported conductor  120  contains terminals that can be received by sockets  175  contained in socket base  170 . After unsupported conductor  120  is mated to sockets  175  in socket base  170 , lens  140  can be fitted to socket base  170  to complete the lamp assembly.  
         [0042]     Other cost and space savings can be realized in some applications by replacing the segments of the processed unsupported conductor as described above with lead wires. In some embodiments, electrical components can be connected to lead wires creating wiring harnesses that contain circuits useful in driving LEDs. A circuit configured in this way may occupy a smaller area than the processed unsupported conductor described above and therefore may be used in some applications requiring tight fits. As mentioned above, in some embodiments of the present invention the lead wires can be referred to as unsupported conductors.  
         [0043]     Turning now to  FIG. 7 , a wiring harness is shown generally at  200 . Harness  200  has incorporated a number of electrical components  210  which are attached to unsupported conductors  220  through crimps  230 . Crimps  230  can be used to eliminate the need to solder the components  210  to unsupported conductors  220  thus protecting harness  200  and components  210  from exposure to high levels of heat which may damage or degrade the performance of some types of components. Components  210  may include resistors, capacitors, and diodes, among others. In some applications, however, it may be appropriate to solder the electrical components to the unsupported conductors. Other methods of attachment are also contemplated such as, but not limited to, ultrasonic welding.  
         [0044]     Electrical components  210  can be protected from the environment, moisture and corrosion using protector  215 . Protector  215  includes, but is not limited to, heat shrink tubing, over-molded protective members, and cable seals.  
         [0045]     Unsupported conductors  220  can serve as a heat sink to reduce the operating temperature of the LED. Unsupported conductors  220  can furthermore be protected by insulation  240 . In some applications, insulation  240  can be appropriately selected and/or designed to accept heat generated by LED  250  and dissipate heat down the length of unsupported conductors  220 .  
         [0046]     LED  250  is attached to the harness  200  through LED crimps  260 . Other attachment methods are also contemplated, such as, but not limited to, electrical connectors, soldering, ultrasonic welding, etc.  
         [0047]     Grommet  270  is shown prior to receiving housing  280 . Housing  280  is adapted to receive LED  250  and wiring harness  200 . Lens  290  covers housing  280  and is furthermore adapted to be received within grommet  270  to form a lamp assembly. The shape of the lamp is depicted as circular in  FIG. 7 , but may also be oval, rectangular or other types as may be desirable depending on the application.  
         [0048]      FIG. 8  depicts a wiring harness  300  having an electrical connector  310 . Electrical connector  310  is capable of receiving LED  250  such that LED  250  can be easily replaced should the need arise. An electrical connector provided as described in this embodiment may permit replacement of LED  250  without the need to replace wiring harness  200 . Similar to the embodiment shown in  FIG. 7 , harness  300  has incorporated a number of electrical components  210  which are attached to unsupported conductors  220  through crimps  230 .  
         [0049]     In some applications, electrical circuits contained in wiring harnesses as described above can be contained in smaller spaces than circuits created from conductive tracks as described above. Wiring harnesses described herein permit mounting in relatively small spaces such as, but not limited to, the rear upper header rail of trailers. Trailer manufacturers may sometimes decrease the space available in the rear upper header rail in an effort to gain more interior storage space. Such space can sometimes be small enough that some lighting devices and their methods of attachment may not be suitable. For example, small spaces may sometimes prohibit the use of rubber grommets as mounting devices depending on the type of lighting device used. Some embodiments of the invention described above may be well suited for the reduced spaces available in the rear upper header rail. The size of the wiring harness in some embodiments may be small enough to fit in the reduced space available in the rear upper header rail. In other embodiments, the relatively small size of the wiring harness and LED combination may allow the use of rubber grommets as mounting devices.  
         [0050]     In another embodiment, a surface mounted version of the wiring harness and LED can be used wherein the wiring harness described above runs in the upper header rail from lamp to lamp creating a driving circuit useful in powering multiple LEDs.  
         [0051]     Many embodiments of the present invention are contemplated and are not limited to a single lamp or function or shape of the lamp. Certain embodiments can be used in many types of lamps including, but not limited to, automotive lamps such as stop lamps, turn signal lamps, tail lamps, license lamps, identification lamps, clearance lamps, dome lamps, side marker lamps, headlamps, parking lamps, and cornering lamps, just to name a few.  
         [0052]     It will be understood by those skilled in the art that the unsupported conductors can be packaged as part of kits sold and/or marketed in retail outlets, wholesale outlets, as well as sold and/or marketed over the phone, television, internet, or any other remote types of marketing and sales. It will also be understood that the unsupported conductors can be used to retrofit existing vehicles, or can be installed as kits onto newly manufactured vehicles.  
         [0053]     While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character. Only certain embodiments have been shown and described, and all changes, equivalents, and modifications that come within the spirit of the invention described herein are desired to be protected. Any experiments, experimental examples, or experimental results provided herein are intended to be illustrative of the present invention and should not be considered limiting or restrictive with regard to the invention scope. Further, any theory, mechanism of operation, proof, or finding stated herein is meant to further enhance understanding of the present invention and is not intended to limit the present invention in any way to such theory, mechanism of operation, proof, or finding. Thus, the specifics of this description and the attached drawings should not be interpreted to limit the scope of this invention to the specifics thereof. Rather, the scope of this invention should be evaluated with reference to the claims appended hereto. In reading the claims it is intended that when words such as “a”, “an”, “at least one”, and “at least a portion” are used there is no intention to limit the claims to only one item unless specifically stated to the contrary in the claims. Further, when the language “at least a portion” and/or “a portion” is used, the claims may include a portion and/or the entire items unless specifically stated to the contrary. Finally, all publications, patents, and patent applications cited in this specification are herein incorporated by reference to the extent not inconsistent with the present disclosure as if each were specifically and individually indicated to be incorporated by reference and set forth in its entirety herein.