Abstract:
A multi-voltage compatible track system which has a single adapter for both 120 Volts and 277 Volts track systems. The systems further comprise a variable input voltage ballast capable of operating with both 120V and 277V input while operating properly.

Description:
CROSS-REFERENCE TO RELATED DOCUMENTS 
     None 
     TECHNICAL FIELD 
     This present invention is related to track lighting. More specifically, the present invention is related to a track lighting system utilizing an adapter which is operable with both 120 Volts and 277 Volts track assemblies. 
     BACKGROUND 
     227 Volts adapters for track lighting systems are typically designed specifically for 277 Volts tracks. Similarly, 120 Volts adapters are typically designed for 120 Volts tracks. The 120 Volts adapters are designed with features, called rejection tabs, which prevent the 120 Volts luminaire from being energized on a 277 Volts track system. 
     This safety feature requires, however, that a track adapter be designed for each of 120 Volts and 277 Volts track lighting systems. In addition to the track adapter, the luminaire fixtures must also be designed for each of the 120 Volts and 277 Volts track assemblies. These factors both complicate product lines, manufacturing and increase costs. 
     It would be desirable to overcome these and other deficiencies and utilize a single track head adapter which may be utilized with luminaires with both 120 Volts and 277 Volts track assemblies. It would also be desirable to provide a track head adapter to utilize with prior art 120 Volts track assemblies but wherein the track system does not allow a prior art 120 Volts track head adapter to be energized on a 277 Volts track system. 
     SUMMARY 
     A downward voltage compatible track lighting system comprises a variable input voltage ballast in electrical communication with a track head adapter, the track head adapter having a contact holder, a first electrical contact extending from the contact holder and a second electrical contact extending from the contact holder, at least one of the first and second electrical contacts extending from the contact holder a first distance R 1 , a track having an opening for receiving a track liner, the track liner disposed within the opening of the track, the track liner having at least a first upper cavity and at least a second lower cavity corresponding to the first electrical contact and the second electrical contact respectively, a sidewall extending between the first upper cavity and the second upper cavity, the sidewall disposed at a second distance R 2  from the contact holder, wherein the second distance R 2  is less than the first distance R 1 . The downward voltage compatible track lighting system wherein the track head adapter is usable with both 120 Volts and 277 Volts track liners. The downward voltage compatible track lighting system further comprising a housing for storage of the ballast. The downward voltage compatible track lighting system further comprising a spacer disposed on the ballast. The downward voltage compatible track lighting system wherein the spacer positions the ballast against a surface of the housing wherein the housing functions as a heat sink for the ballast. The downward voltage compatible track lighting system further comprising a spacer on a ballast, the spacer positioning the ballast away from a light fixture connected to a ballast housing. The downward voltage compatible track lighting system further comprising a pin connected to the track head adapter, the contact holder being pivotable from a first position to a second position to one of engage or disengage the track liner. 
     A downward voltage compatible track lighting system comprises a track head adapter providing electrical communication between a track light fixture to an electrified track assembly, a variable voltage ballast in electrical communication with the track head adapter and the track light fixture, the track head adapter having a contact holder, a first electrical contact extending from the contact holder and a second electrical contact extending from the contact holder, a length defined between the first electrical contact and the second electrical contact, a track having an opening for receiving a track liner, the track liner receiving the track head adapter, the track liner having a first cavity corresponding to the first electrical contact and a second cavity corresponding to the second electrical contact, a sidewall extending between the first cavity and the second cavity, the sidewall being inset from ends of the first cavity and the second cavity toward the contact holder and inhibiting positioning of tabs on the contact holder between the electrical contacts due to interference with the sidewall. The downward voltage compatible track lighting system wherein the track head adapter is usable with track voltages of 120 Volts and 277 Volts. The downward voltage compatible track lighting system wherein the track head adapter being usable with a luminaire housing assembly. The downward voltage compatible track lighting system wherein the track head adapter is usable with a pendant light fixture. The downward voltage compatible track lighting system wherein the track head adapter has a loading bar. The downward voltage compatible track lighting system wherein the electrical contacts extending upwardly above the loading bar. The downward voltage compatible track lighting system further comprising a locking plate disposed above the loading bar, the locking plate engaging the track. The downward voltage compatible track lighting system further comprising an insulator post extending between the first electrical contact and said second electrical contact. 
     A downward voltage compatible track lighting system, comprises a track head adapter in electrical communication with an energized track assembly, a variable voltage ballast and a track lighting fixture, the track head adapter having an upper electrical contact and a lower electrical contact, the upper electrical contact spaced apart a distance from the lower electrical contact and defining a gap, the track assembly having a track and a track liner extending through an opening in the track, the track liner receiving the track head adapter, the track liner having a first cavity and a second cavity for receiving the first and second contacts, respectively, the first and second cavities defining a gap therebetween, an inner surface of a track liner sidewall disposed inwardly of an outermost point of at least one of the electrical contacts, the sidewall having a position which inhibits use of tabs on the contact holder disposed between the first cavity and the second cavity. The downward voltage compatible track lighting system wherein the track head adapter is compatible with either of 120 Volts and 277 Volts electrical sources. The downward voltage compatible track lighting system further comprising a pendant light fixture. The downward voltage compatible track lighting system further comprising a downlight fixture. The downward voltage compatible track lighting system further comprising a grounding clip which engages the track. 
    
    
     
       BRIEF DESCRIPTION OF THE ILLUSTRATIONS 
       Embodiments of the invention are illustrated in the following illustrations. 
         FIG. 1  is a perspective view of a track lighting system; 
         FIG. 2  is an exploded perspective view of the track lighting system of  FIG. 1 ; 
         FIG. 3  is an exploded perspective view of the track head adapter of the track lighting system of  FIG. 1 ; 
         FIG. 4  is an end view of a track assembly having a track liner utilized with 120 Volts power source; 
         FIG. 5  is an end view of a track assembly having a track liner utilized with 277 Volts powers source; 
         FIG. 6  is an end view of a track lighting system having the track assembly of  FIG. 4  and a track head adapter for use with 120 Volts or 277 Volts track assemblies; 
         FIG. 7  is an end view of the track lighting system having the track assembly of  FIG. 5  and a track head adapter for use with 120 Volts or 277 Volts track assemblies; 
         FIG. 8  is a perspective view of a troffer fixture which may be used; 
         FIG. 9  is a section view of the troffer of  FIG. 8 ; 
         FIG. 10  is a bottom view of the troffer fixture of  FIG. 8 ; and, 
         FIG. 11  is a side-section view of a pendant light track head adapter. 
     
    
    
     DETAILED DESCRIPTION 
     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 drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless limited otherwise, the terms “connected,” “coupled,” and “mounted,” and variations thereof herein are used broadly and encompass direct and indirect connections, couplings, and mountings. In addition, the terms “connected” and “coupled” and variations thereof are not restricted to physical or mechanical connections or couplings. 
     A downward compatible voltage track lighting system is shown in the various  FIGS. 1-11 . The system utilizes a track head adapter which is usable with both 120 Volts and 277 Volts track assemblies in order to provide functionality between track assemblies and fixtures of either voltage. The track lighting system functions to allow use of a single track head adapter and a track assembly with either 120 Volts power source or 277 Volts power source. Accordingly, with such system, separate track head adapters are not needed for each of the different voltages which are commonly utilized in track lighting systems. However, the track head adapter allows backward compatibility with 120 Volts track assemblies while also inhibiting use of prior art 120 Volts track head adapters with 277 Volts track assemblies. 
     Referring initially to  FIG. 1 , a track lighting system  10  is depicting having a track assembly  12 , a track head adapter  14  and at least one light fixture  16 . The track lighting system  10  includes an upper track assembly  12  which is connected to a ceiling. A track head adapter  14  slides within the track assembly  12  and connects a ballast  60  ( FIG. 2 ) and light fixture  16  to the electrified track assembly  12 . Beneath the track head adapter  14  is a ballast housing  18  wherein the variable voltage ballast  60  ( FIG. 2 ) is positioned and is in electrical communication with the track head adapter  14  and the track head assembly  12 . A variable voltage ballast  60  ( FIG. 2 ) receives input voltage of 120 Volts or 277 Volts from the track assembly and provides a suitable power a lamp within the light fixture  16 . Various lamp types may be used based on lighting needs, fixture type, desired voltage and other factors as will be understood my one skilled in the art. 
     Referring now to  FIG. 2 , an exploded perspective view of the track lighting system  10  is depicted. The track assembly  12  includes a track or track portion  20  which is defined by first and second sidewalls  22 ,  24  and a cross-brace  26 . The track  20  may be linear or curvilinear. The area above the cross-brace  26  receives a hanger assembly (not shown) for connection of the track assembly  12  to the ceiling. The lower area beneath the cross-brace  26  receives a liner  30 ,  130  ( FIG. 5 ) which provides an electrical connection to the track head adapter  14 . In turn, this provides the electrical communication between the ballast  60 , and the power source which is electrically connected to the track assembly  12 . 
     Adjacent the track assembly  12  is the track head adapter  14  comprising a housing adapter  40 , a housing disc  42  and a contact holder  44 . The housing adapter  40  is fastened to the housing disc  42  and connected to a ballast housing upper plate  56 . The housing adapter  40  and housing disc  42  are generally circular in shape although not limited to such shape. Each have coaxial central apertures  41 ,  45  through which the contact holder  44  passes downwardly there through. The housing adapter  40  and the housing disc  42  are fixed relative to the housing upper plate  56  and a pin  43  is connected to the contact holder  44  allowing rotation of the contact holder  44  about a vertical axis relative to the housing adapter and housing disc  40 ,  42 . 
     Beneath the track head adapter  14  are first and second contacts  50 ,  52 . Disposed between the contacts  50 ,  52  is an insulator post  54  which inhibits touching of the contact  50  and the contact  52 . According to the instant embodiment, one of the contacts  50 ,  52  may be a hot conductor and the other of the contacts  50 ,  52  may be a neutral conductor. The contacts  50 ,  52  are connected to wires which extend to and are in electrical communication with a ballast  60 . A ground clip  48  ( FIG. 3 ) is positioned on the track head adapter  14 . The first and second contacts  50 ,  52  and the insulator post  54  extend upwardly through the housing plate  56 , and more specifically through the central aperture  59  in the housing upper plate  56 . The pin  43  is connected to the contact holder  44  wherein the first and second contacts  50 ,  52  are positioned. Pivoting of the pin  43  about a vertical axis therefore causes rotation of the contact holder  44  and the contacts  50 ,  52  to either engage or disengage a bus bar in the track liner  30 . 
     Still referring to  FIG. 2 , beneath the upper plate  56  and electrically connected to the first and second contacts  50 ,  52  by a plurality of wires is the ballast  60 . More specifically, the ballast  60  is a variable input voltage ballast which allows input power of 120 Volts as well as 277 Volts from the track assembly. Additional voltages may be utilized based on the type of ballast used with the embodiment. The ballast  60  includes a spacer  62  located on one surface of the outer structure. The spacer  62  is, according to the exemplary embodiment, a spring which forces or positions the ballast  60  away from the fixture  16  when the ballast  60  is positioned in the housing  18 . This causes the ballast  60  to contact the housing  18  on a surface opposite the fixture  16 , allowing the housing  18  to act as a heat sink for the ballast  60  and also spacing the ballast  60  away from the high temperature fixture  16 . At the bottom portion of the housing  18  is a lower plate  57 . Connected to the lower plate by fastener is the fixture  16 . The downlight fixture  16  of the exemplary embodiment is pivotable about a horizontal axis defined by the fastener so that the light output from the fixture  16  may be aimed to a desirable location within the room for illumination. However, as will be understood further, the track lighting assembly  10  may comprise multiple luminaire types. 
     Referring now to  FIG. 3 , an exploded perspective view of the track head adapter  14  is shown more closely. The housing adapter  40  is positioned above the housing disc  42 . The housing disc  42  has a sidewall with a gap  42   a  through which the rotation pin  43  extends. Adjacent the housing adapter  40  is a ground clip  48  which provides a grounding conductor for the track head adapter  14  to the track assembly  12 . The clip  48  has first and second ends which engage shoulders  28 ,  128  (FIGS.  4 , 5 ) on the track assembly  12 . The housing adapter  40  is connected by three fasteners to the housing disc  42  so that the two structures are rigidly connected. The gap  42   a  and the housing disc therefore allows the pin  43  to pass between the housing disc  42  and housing adapter  40  as the pin  43  and contact holder  44  are rotated. 
     The contact holder  44  is shown disposed above the adapter  40 . During installation, the contact holder  44  is positioned downwardly through the central opening  41 ,  45  in the housing adapter  40  and the housing disc  42  in order to place the lower portion  49  of the cylindrical contact holder  44  over the contacts  50 ,  52 . More specifically, the upper portion of the contact holder  44  is opened so that end tab  51  of contact  50  extends through this upper aperture and outwardly there from. Contact holder  44  also includes an aperture  45  through which the tab  53  of contact  52  extends. The contact older  44  also includes arms  46  extending from the generally cylindrical contact body  49 . The arms  46  are seated on shoulders within the track  20 , as described further herein. 
     Referring now to  FIG. 4 , an end view of the track assembly  12  is depicted. As previously described, the track  20  includes a first wall  22  and a second wall  24  which are spaced apart by a cross-brace  26 . Above the cross-brace  26  are upper shoulders extending inwardly from the sidewalls  22 ,  24 . Beneath the cross-brace  26  are the lower shoulders  28  which also extend inwardly from the walls  22 ,  24 . Disposed within the track  20 , beneath the cross-brace  26  is a liner  30 . The track liner  30  of  FIG. 4  is designed for use with 120 Volts power source. The liner  30  includes first and second sidewalls  32 ,  34  as well as a top wall  36 . The liner  30  also includes upper cavities  33  and lower cavities  35  wherein bus bars  38  are positioned. The bus bars  38  are electrically conductive and are in electrical communication with a power supply (not shown) which electrifies the track assembly  12 . As a result, when the contacts  50 ,  52 , and more specifically the contact tabs  51 ,  53 , are positioned within the bus bars  38  of the upper and lower cavities  33 ,  35 , the power source of the track assembly  12  is then in electrical communication with the track head adapter  14  and ballast  60  and light fixture  16 . Alternatively, when the pin  43  is rotated to disengage the tabs  51 ,  53  from the bus bars  38 , the power supply is no longer in electrical communication with the ballast  60  and fixture  16 . 
     Referring now to  FIG. 5 , an end view of an alternate track assembly  112  is depicted. The track assembly  112  is a 277 Volts track assembly. The track structure  112  is the same as that of track  12  and will not be described again. However, the liner  130  differs in that the sidewalls  132 ,  134  are spaced inwardly from the positions shown and discussed with the 120 Volts liner  30 . Prior art 120 Volts adapters include rejection tabs extending radially outward from the track head adapters. The closely spaced nature of walls  132 ,  134  as opposed to walls  32 ,  34  inhibit use of those adapters with the closely spaced sidewalls  132 ,  134 . However, the closely spaced sidewalls  132 ,  134  inhibit positioning of these track heads with rejection tabs therein inhibiting rotation of the contacts into the bus bars of upper and lower cavities. In short, this inhibits use of an older-type 120 Volts adapter with 277 Volts track assembly. 
     Referring now to  FIG. 6 , an end view of the track head adapter  14  and track assembly  12  is shown with the adapter  14  disposed therein. The embodiment depicts a track liner which is for use with 120 Volts tracks. The track head adapter  14  is usable with these older 120 Volts track assemblies as well as 277 Volts. However, prior art 120 Volts adapters having rejection tabs are not usable with the track liner  130 . The electrical contacts  50 ,  52  are positioned within the bus bars  38  of the upper and lower cavities  33 ,  35 . In this position, the electrified track assembly  12  is in electrical communication with the ballast  60  and the connected light fixture  16 . Extending from the contact holder  44 , the arms  46  are shown seated on the lower shoulders  28  of the track  20 . 
     Referring now to  FIG. 7 , the track head  14  is depicted as positioned within the track assembly  112  and engaging the bus bars  138  in the upper and lower cavities  133 ,  135  of the track liner  130 . The track liner  130  is usable with the track head adapter  14  but inhibits use with prior art 120 Volts adapters. However, the adapter  14  of the system may be utilized with prior art 120 Volts track liner, rendering the system backward compatible while inhibiting use of prior art 120 Volts luminaire in a 277 Volts track. 
     In comparing  FIG. 6  and  FIG. 7 , the track liner of  FIG. 7  has a distance R 2  indicated from a centerline of the track head. The distance R 2  is less than the distance R 1 , which measures the tip of the electrical contact  50  to a centerline of the track head adapter  14 . Alternatively stated, the liner sidewall  132 ,  134  of the 277 Volts track assembly  112  are inset from the outer edges of the track liner which are defined by the cavities  133 ,  135 . Since the sidewalls  132 ,  134  are inset and closely spaced to the upper portion of the contact holder  44 , a track head adapter having rejection tabs, such as those known in prior art, for use in 120 Volts systems may not be utilized with the track liner  130 . However, the track head adapter  14  may be used with 120 Volts track assembly  12  as shown in  FIG. 6  with the use of universal or variable input voltage ballast  60 . In short, the track head adapter  14  may be used with prior art track liners, however, prior art 120 Volts track head adapter cannot necessarily be used with the track liner  130 . 
     Referring now to  FIGS. 8-10 , an alternative embodiment of a light fixture is shown being utilized with the track head adapter form  114 . The fixture  116  is a troffer fixture, rather than the downlight type fixture previously shown. The troffer fixture  116  includes an upper housing  162  extending between and pivotally connected to first and second arms  164 ,  166 . The upper portion of one of the arms  164 ,  166  includes the upper track head adapter  114  which engages the track  12 ,  112 . As previously described, the instant track head adapter  114  may be utilized with either track assembly  12 ,  112  as previously described. This allows the troffer fixture  116  to be utilized on 120 Volts track assemblies or 277 Volts track assemblies. Disposed within the housing  162  is a variable input voltage ballast  160  ( FIG. 9 ). The ballast regulates the voltage from the track assembly  12 ,  112  also allowing use of the track fixture  116  with different voltages. 
     Depending from the housing  162  is a reflector  168 . The reflector  168  is generally parabolic in shape and may be directionally adjusted by utilizing the pivotal connection between the arms  164 ,  166  and the housing  162 . The troffer fixture  116  therefore may be positioned in a track assembly  12 ,  112  and moved along the track assembly to a desirable position. 
     Referring now to  FIG. 11 , a cross-section view of an alternate track head adapter  214  is depicted for use with a pendant light fixture. The track head adapter  214  includes first and second contacts  250 ,  252  as well as an insulator post  254 . Wiring connections pass downwardly through a cap structure  218  and extend downwardly to a ballast (not shown) and a fixture (not shown). The track head adapter  214  in combination with the variable input voltage ballast allows use of the fixture of this embodiment with track assemblies having differing voltages. 
     The foregoing description of several embodiments of the invention has been presented for purposes of illustration. It is not intended to be exhaustive or to limit the invention to the precise steps and/or forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. It is intended that the scope of the invention and all equivalents be defined by the claims appended hereto.