Lighting assembly for multiple fluorescent lamps

Information

  • Patent Grant
  • 6217190
  • Patent Number
    6,217,190
  • Date Filed
    Monday, September 21, 1998
    26 years ago
  • Date Issued
    Tuesday, April 17, 2001
    23 years ago
Abstract
A fluorescent lighting assembly (2) includes a ballast lampholder subassembly (4) located at one end of a troffer (80) and at least one lampholder connector (50) located at the opposite end. The ballast lampholder subassembly (4) includes ballast circuitry connected to fluorescent lamp terminals (17) all positioned within a ballast lampholder housing (6). A molded ballast lampholder cover (8) encloses three sides of the ballast lampholder subassembly and a stamped metal plate forms the ballast lampholder base (10), with the ballast circuitry located on a circuit board (27) positioned on the interior surface of the base. Integrally molded lampholders (15) extend from channels (14) on the cover (8) and are positioned between larger enclosure sections (12) which provide space for larger ballast components. Fluorescent lamp terminals (17) are inserted from the interior of the cover into cavities (16) in lampholders (15), and lead wires connect the terminals to the printed circuit board. Lampholder connectors (50) including integrally molded lampholders (51) are located at the opposite end of the fluorescent lighting assembly (2).
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




This invention is related to lighting assemblies and is more particularly related to fluorescent lighting assemblies using electronic ballasts. More particularly, this invention is related to a fluorescent subassembly or lampholder including ballast components and integral fluorescent sockets.




2. Description of the Prior Art




Conventional ballasts used in overhead troffers or luminaires include lamps, ballasts and socket subassemblies or lampholders. The ballast or ballasts are mounted at the center of the troffer and attached to the top of the troffer. Wires extend from the ballast or ballasts to sockets located at opposite ends of the troffer. For a four lamp assembly, wires must be connected to sockets at both ends of the four lamps. When a defective ballast is replaced, often on a trial and error basis, these wires must be disconnected and reconnected. Installation and maintenance of conventional lighting assemblies is therefor time consuming and the manufacturing cost of the lighting assembly is increased.




One approach to simplifying and therefore reducing the cost of ballast installation is disclosed in U.S. Pat. No. 5,720,546 assigned to The Whitaker Corporation. This patent discloses an integral ballast that can be mounted at one end of a lighting assembly. A neutral wire is connected to the opposite end of the lighting assembly and this wiring must be completed during assembly of the lighting fixture. U.S. patent application Ser. No. 08/967,534 discloses a lighting assembly in which a ballast subassembly, including a ballast circuit similar to the MULTILITE MUL120 ballast circuit, can be mounted on a single end of a troffer with commoning contacts located at the opposite end. The ballast components are mounted on a printed circuit board positioned in a metal housing with conventional fluorescent sockets mounted on the exterior of the housing and connected to the printed circuit board.




U.S. Pat. No. 5,013,253 discloses another approach to simplifying the construction of fluorescent lighting fixtures. This patent discloses a method of wiring an otherwise conventional fluorescent lampholder in which wire leads are positioned in an insulating housing to connect terminals in integrally molded lamp sockets with an external connector block. Conventional external ballasts can then be wired to lamp sockets using this external connector block.




SUMMARY OF THE INVENTION




The principal objective of the instant invention is to simplify the assembly of fluorescent ballasts and of fluorescent lighting assemblies. By simplifying the manufacture of these assemblies they can be made more cost effective. The instant invention achieves these manufacturing improvements not only by changes to the assembly procedure, but by changes to the components themselves, which permit changes to the manufacturing procedure.




According to the invention, a fluorescent lighting assembly includes a ballast lampholder subassembly and at least one lampholder connector. The ballast lampholder and the at least one lampholder connector are located at respective opposite ends of the fluorescent lighting assembly with fluorescent lamps or tubes extending between. In a preferred embodiment, the ballast lampholder subassembly and the lampholder connector are mounted on a fluorescent lighting troffer. Each of the housings for both the ballast lampholder subassembly and the lampholder connector include a molded housing part. In a preferred embodiment, a plurality of lampholders comprise integrally molded extensions of this molded housing part, such as the cover for the ballast lampholder subassemblies. The lampholders include terminal cavities into which fluorescent lamp terminals can be inserted. Wires are crimped to these terminals before insertion into the terminal cavities, and these wires are then used either to attach the terminals to the ballast circuitry on the interior of the housing or to other terminals.











BRIEF DESCRIPTION OF THE DRAWINGS




The invention will now be described by way of example with reference to the accompanying drawings wherein:





FIG. 1

is an exploded view showing the basic components of a fluorescent lighting assembly that can be used with fluorescent lights in a fluorescent ceiling unit;





FIG. 2

is an exploded view showing the components of a ballast lampholder subassembly;





FIG. 3

is a side view of the housing of the ballast lampholder subassembly;





FIG. 4

is a section view of the housing shown in

FIG. 3

;





FIG. 5

is a bottom view showing the interior of the housing shown in

FIG. 3

;





FIG. 6

is a view showing an individual lampholder of the type which can be used on the ballast lampholder subassembly or on the lampholder connector subassembly;





FIG. 7

is a view of the components of a lampholder connector subassembly;





FIG. 8

is a bottom view of a lampholder connector subassembly;





FIG. 9

is a view of a three lamp ballast lampholder subassembly used in another embodiment of the invention;





FIG. 10

is a view of a three lamp lampholder connector used with the ballast lampholder subassembly shown in

FIG. 9

to form a three lamp fluorescent lighting assembly; and





FIG. 11

is a view showing the manner in which fluorescent lamp terminals are attached to a bus wire in the embodiment of FIGS.


9


and


10


.











DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT




The fluorescent lighting assembly


2


as shown in

FIG. 1

is intended to mount four conventional fluorescent lamps in a ceiling. This lighting assembly includes a ballast lampholder subassembly


4


located on a first end


38


of the lighting assembly, fluorescent lamps


30


extending between the first end


38


and the second end


40


of the lighting assembly


2


, lampholder connectors


50


located at the second end


40


and a troffer


80


in which the other components are mounted. The preferred embodiment of this lighting assembly is of the type that could be mounted in a suspended ceiling in an office building. The lighting assembly


2


and the troffer


80


are shown in an inverted position in

FIG. 1

so that the surface of the troffer, facing downward when installed, is visible. This lighting assembly


2


can employ conventional fluorescent lamps


30


. In the preferred embodiment the lighting assembly


2


and the ballast lampholder subassembly


4


are of the type that would be used with instant start T-8 fluorescent lamps. The ballast subassembly


4


is an electronic ballast of the type that can energize two eight foot fluorescent lamps or four lamps that are each four feet in length as in this embodiment.




The components of the ballast lampholder subassembly


4


are shown in the exploded view of FIG.


2


. Ballast lampholder subassembly


4


is an integral unit or hub comprising a ballast housing


6


(

FIG. 1

) that includes a housing cover


8


attached to a housing base


10


that encloses the electronic ballast circuitry and components on the interior of the housing


6


. The housing cover


8


is molded from a thermoplastic and the housing base


10


can be fabricated from sheet metal or plastic. In the preferred embodiment, the housing base


10


is a stamped metal plate that serves as a grounding member when connected to the metal troffer


80


(FIG.


1


).




The housing cover


8


is attached to the housing base


10


to form the housing


6


enclosing the fluorescent ballast. With reference also to

FIG. 3

, the housing cover


8


has opposite sides


8




a,




8




b


and top


8




c


which enclose three sides of the housing


6


. The cover


8


extends between ends


8




d


and


8




e


(

FIG. 2

) that would be adjacent to the opposite interior surfaces of a lighting assembly


2


. The housing base


10


encloses the fourth side of the housing


6


.




As shown in

FIGS. 2 and 3

, ballast lampholder housing cover


8


includes three protruding housing areas


12


that provide room for the larger components in the power supply circuit and the ballast circuit of the electronic ballast. Four channels


14


are located on the top of the ballast subassembly


4


and extend between and on either side of the protruding housing areas or enclosures


12


. Channels


14


provide space for mounting fluorescent lamps


30


in fluorescent lampholders


15


that have a conventional mounting configuration. A fluorescent lamp lampholder


15


is located in each channel


14


to engage pins on the first base of a fluorescent lamp


30


. These lampholders


15


are integrally molded as part of the housing cover


8


.




With reference also to

FIGS. 5 and 6

, each of the lampholders


15


has a pair of terminal cavities


16


in which fluorescent lamp terminals


17


are positioned. The lampholders


15


have a conventional lamp mounting configuration and are intended to receive one end of a bi-pin fluorescent lamp


30


. The terminal cavities


16


open onto an interior surface of the housing cover


8


so that the terminals can be inserted into the integrally molded lampholders


15


. The fluorescent lamp terminals


17


each include a terminal spring


18


and a crimp barrel


19


that attaches the terminal


17


to the stripped end of an insulated lead wire


20


. Terminal springs


18


of opposed terminals


17


face the center of the lampholder


15


and are deflected outwardly when a bi-pin lamp


30


is rolled into the lampholder


15


. In the preferred embodiment terminals


17


comprise stamped and formed terminals manufactured by AMP Incorporated as Part Number 640483.




As shown in

FIG. 5

, the housing cover


8


also includes splicing terminal mounting pockets


23


molded on the interior of the cover


8


. A conventional insulation displacing splicing terminal can be inserted into each pocket


23


to splice wires spanning the pocket


23


. External power lead wires


26


can be spliced to wires extending from a printed circuit board


27


, shown in

FIG. 2

, containing ballast circuitry and ballast components. The wires


26


are suitable for supplying external electrical power to the ballast subassembly. The splicing terminal in each pocket


23


comprises a conventional terminal manufactured by AMP Incorporated as part number 62833-1 and the pocket


23


is configured to receive this terminal. The splicing terminal includes parallel insulation displacement slots each having parallel beams which engage the wires


26


to not only establish an electrical connection, but also to establish a redundant termination to the wire to provide an effective mechanical strain relief without additional components. Other leads (not shown) can be attached to a poke-in section of each splicing terminal and these leads are attached to other components in the ballast subassembly. In addition to other components of an electronic ballast, the printed circuit board


27


includes larger components such as output inductors


28


and a choke


29


as shown in FIG.


2


. These larger components are positioned on the printed circuit board


27


so that they can be mounted in the larger enclosure sections


12


between the lampholders


15


. As shown in

FIG. 1

, the ballast lampholder subassembly


4


is mounted on only one end of the lighting assembly


2


and the troffer


80


.




Fluorescent lamps


30


are conventional tubular fluorescent lamps with a first bi-pin base


32


at one end and a second bi-pin base


34


at the opposite end. Two pins


36


at each end are conventional. Fluorescent lamps


30


are instant start lamps with a conventional instant start electrode (not shown) connected to the pins


36


at the ends of the glass envelope forming the lamp


30


. In the preferred embodiment the fluorescent lamps


30


are used with a suitable instant start electronic ballast circuit and power supply circuit such as that used in the MULTILITE MUL120 manufactured and sold by Electrofab, Ltd. The components of this ballast circuitry are included on printed circuit board


27


. The pins


36


fit within the lampholders


15


which are part of the ballast subassembly


4


. The lamps


30


can be rolled into position in the lampholders in a conventional manner. Since the preferred embodiment of this invention employs instant start fluorescent lamps, it should be understood that instant start fluorescent lamps having a single pin on each base could also be employed with suitable lampholdrs. This invention could also be employed with preheat fluorescent lamps and a suitable preheat electronic ballast.




In this invention, only the first base


32


of each fluorescent lamp


30


is connected directly to the electronic ballast in ballast lampholder subassembly


4


. The opposite second base


34


and the pins


36


therein are connected to lampholders in a lampholder connector


50


. The preferred embodiment of this invention is intended to be used with multiple fluorescent lamps


30


, and in the four lamp version of this invention, the fluorescent lamps are paired so that for each pair of fluorescent lamps, the respective first base


32


is attached to the ballast and the respective second bases


34


of the two lamps in each pair are electrically commoned in the lampholder connector


50


. In the preferred embodiment of

FIGS. 1-8

, the pins


36


in the second base


34


of one lamp in each pair of lamps are connected to the corresponding pins


36


in the other lamp of that pair of lamps. For this invention, only the first bases


32


at the first end


38


of the lighting assembly will be energized to start the lamps. No current will flow through the pins


36


in the second bases


34


of the fluorescent lamp pairs until an arc is established between the opposite ends of each lamp


30


. By using an electronic ballast, such as the MULTILITE MUL120 manufactured and sold by Electrofab, Ltd., that is capable of operating fluorescent lamps of twice the length of the lamps


30


, it then becomes possible to common the second bases


34


through one of the lampholder connectors


50


. The electronic ballast used in ballast subassembly


4


is also capable of operating two separate pairs of fluorescent lamps, so the preferred embodiment employs two pairs or four lamps


30


.




With reference to

FIGS. 9 and 10

, ballast lampholder subassembly


104


and lampholder connector


150


are three lamp versions of the lampholder subassembly


4


and lampholder connector


50


, respectively. The ballast lampholder subassemblies


4


,


104


and the lampholder connectors


50


,


150


are fabricated and assembled so that the cost of the fluorescent lighting subassembly can be significantly reduced. By molding the lampholder cover


8


and the corresponding cover for the three lamp version


104


with integrally molded lampholders


15


, the cover can be used to simplify assembly. This is best appreciated by referring to FIG.


2


. The fluorescent lamp terminals


17


can be crimped to wires


20


and inserted into the lampholders


15


with the wires extending downward from the cover


8


. Opposite ends of these wires


20


can then be attached to the printed circuit board


27


either by soldering or by inserting terminals crimped to the wire ends onto pins soldered to the printed circuit board. For example, a receptacle, such as AMP Incorporated part number 61291, can be crimped to the end of each wire


20


, and it can be mated to a pin, such as AMP Incorporated part number 61137, previously soldered to the printed circuit board


27


. This approach simplifies hand wiring of the fluorescent lamp terminals to the ballast circuitry on the printed circuit board. Next, the printed circuit board can be positioned on the interior surface of the housing base


10


. If the housing base


10


comprises a stamped metal plate, the ballast circuit can be grounded to this base, which can in turn be attached by screws or other fasteners to the metal troffer


80


(

FIG. 1

) when the ballast lampholder subassembly


4


is placed in service. Power wires


26


are attached to the ballast circuitry by using a splicing terminal in a pocket


23


in the manner which was discussed previously with reference to FIG.


5


. After the internal components have been assembled in this manner, the housing base


10


can be snapped to the housing cover


8


to complete the assembly of the ballast lampholder subassembly


4


.




The integral ballast lampholder subassembly


4


and the lampholder


50


can be mounted on troffer


80


as shown in FIG.


1


. Troffer


80


is generally conventional in construction having a top wall


82


, two end walls


84


at the first and second ends of the lighting assembly and two side walls. Since the ballast lampholder subassembly


4


is mounted at an end of the troffer


80


, the four fluorescent lamps


30


can be mounted in the troffer on substantially equally spaced centerlines without the need for additional space between the two center fluorescent lamps to accommodate a conventional ballast.




With reference to

FIGS. 1

,


7


and


8


, the lampholder connector subassemblies


50


which are located at the opposite end of the troffer


80


include a molded housing with connector lampholders


51


molded to the housing in much the same manner as for the ballast lampholder subassembly


4


. Fluorescent lamp terminals


17


as previously described are inserted into the lampholders


51


. However, the terminals in the lampholder connector subassembly need not be connected to the ballast. These fluorescent lamp terminals


17


merely connect corresponding pins of multiple fluorescent lamps


30


. Therefore these fluorescent lamp terminals


17


can be joined by wires


57


extending between two terminals in different connector lampholders


51


. Each wire


57


joins two corresponding terminals


17


in two lampholders


51


. In the embodiment shown, two connector lampholders


51


are located at opposite ends of a connector base


53


. Terminal cavities


52


in each connector lampholder


51


open onto an open lower surface or trough


54


of the connector housing. The wire leads


57


extending between two spaced-apart lampholders


51


are disposed in this trough


54


on the underside of the lampholder base


53


. The wire leads


57


are held in the trough


54


by molded-in raised nubs that keep the wire leads tucked into the troughs


54


for wire management and to prevent the wire leads


57


from dangling out of the troughs


54


. The same basic approach shown for the two-lamp lampholder connector


50


can be used for a four-lamp lampholder. For both the two-lamp and four-lamp versions the same terminal subassembly comprising two fluorescent lamp terminals


17


connected by a wire lead


57


could be used, because the length of the wire lead


57


would be the same.




Lampholder connectors


50


also include mounting tabs


58


extending from opposite sides of the lampholders


51


. These tabs


58


can be inserted into slots (not shown) on the end walls


84


of the troffer


80


to mount the lampholder connectors


50


with connector lampholders


51


in alignment with the lampholders


15


on the ballast lampholder subassembly


4


at the opposite end of the lighting fixture assembly


2


. The two dual position lampholder connectors


50


shown in

FIGS. 1 and 7

do not need to be connected to the ballast circuitry in the ballast lampholder subassembly


4


because the electronic ballast circuit used in this embodiment can be used to initiate and power two four foot lamps


30


. One of the dual lampholder connectors


50


connects the opposite ends of two side-by-side fluorescent lamps


30


.




A second embodiment of this invention is shown in

FIGS. 9 and 10

. This embodiment uses a three-lamp ballast lampholder subassembly


104


and a three-lamp lampholder connector


150


. The three-lamp ballast lampholder subassembly


104


includes a ballast circuit for use in a three-lamp lighting fixture, but in most other respects is constructed in the same manner as the four-lamp version. The principal difference is that the three-lamp ballast lampholder subassembly


104


includes a wire


105


that connects the three-lamp ballast lampholder subassembly


104


to the three-lamp lampholder connector


150


located at the opposite end of the fluorescent lamps in a three-lamp lighting fixture. This wire


105


is connected to the ballast lampholder subassembly


104


in substantially the same manner as to the lampholder connector


150


, and attachment of this wire will be discussed with reference to the lampholder connector


150


. The three-lamp lighting fixture thus can operate in much the same manner as that described in U.S. Pat. No. 5,720,546 which is incorporated herein by reference.




As shown in

FIG. 10

, lampholder connector


150


includes three lampholders


151


with two terminal cavities


152


in each lampholder


151


. The same terminals


17


are used in this three-lamp lampholder connector


150


. The lampholder connector


150


also includes two pockets


160


located adjacent to the terminal cavities


152


in each lampholder. In addition to the six pockets


160


, a seventh pocket


155


is located adjacent to the central lampholder. Each of these molded pockets is configured to receive a splicing terminal


56


, shown in

FIG. 11

, which in a preferred embodiment comprises a conventional terminal manufactured by AMP Incorporated as part number 62833-1. As shown in

FIG. 10

, a single bus wire


157


extends between opposite ends of the three-lamp lampholder


150


, and this single bus wire


157


extends through all of the pockets


155


and


160


. Each pocket includes slots on either side so that the bus wire


157


can be laced through the slots so as to span the corresponding pockets


155


and


160


. After the bus wire


157


has been inserted into each of the pockets, a splicing terminal


56


is inserted into each pocket. Each splicing terminal


56


includes two insulation displacement slots defined by opposed metal edges which engage the bus wire


157


to form a gas tight permanent electrical connection to the bus wire


157


in a conventional manner. In addition to the insulation displacement slots, each splicing terminal


56


also includes a poke-in terminal portion which can engage the stripped end of a wire when the stripped end is inserted into the poke-in terminal portion. Alternatively, a spade terminal may be attached to the stripped end of the wire and inserted into the poke-in terminal portion.




The poke-in terminal portion of each splicing terminal


56


is accessible through the open end of its corresponding pocket


160


. As shown in

FIG. 11

, fluorescent lamp terminals


17


located in the cavities


152


are each connected to the common bus wire


157


by a respective lead wire


161


. The stripped end of each lead wire


161


is inserted into the poke-in terminal portion of a corresponding splicing terminal


56


located in a pocket


160


adjacent to a corresponding lampholder cavity


152


. All of the fluorescent lamp terminals


17


in the three-lamp lampholder connector


150


are thus electrically connected to the single bus wire


157


. Therefore, all of the fluorescent lamp terminals


17


in the three-lamp lampholder connector


150


are electrically connected to each other.




The splicing terminal


56


in the seventh pocket


155


, which is also connected to the single bus wire


157


, is used to connect all of the fluorescent lamp terminals


17


in the three lampholders


151


to the ballast subassembly


104


located at the opposite end of the troffer in a three-lamp lighting assembly. A stripped end of wire


105


is inserted into the poke-in terminal portion of the splicing terminal


56


in the pocket


155


, and in this manner the wire


105


, extending the length of the lighting assembly, is connected to the bus wire


157


in the three-lamp lampholder connector


150


. The opposite end of the wire


105


can be connected to the ballast in the ballast subassembly


104


by using a similar splicing terminal


56


, not shown.




Each three-lamp lampholder connector


150


also includes slots


162


on opposite ends. These slots permit the bus wire


157


to extend beyond the ends of the lampholder connector


150


. These slots


162


are aligned with the bus wire


157


and facilitate efficient assembly of the three-lamp lampholder connector


150


. A series of three-lamp lampholder connector housings can be positioned end to end with slots


162


in alignment. A continuous wire can then be laced through troughs on the bottoms of the housings with the continuous wire extending through the slots


162


. A portion of the wire extending between each pair of adjacent housings can be cut, thereby severing the wire connection between the adjacent housings. In this way, separate lampholder connectors can be wired in an efficient manner.




The three-lamp version of this lighting assembly shown in

FIGS. 9-11

differs from the two or four-lamp version because all of the fluorescent lamp terminals


17


in the three-lamp version of the lampholder connector


150


are electrically connected. Therefore, two terminals


17


connected to two pins in the same fluorescent lamp are electrically commoned in the three lamp version. For the two-lamp lampholder connector


50


of

FIGS. 7 and 8

, the terminals


17


which are connected to the same lamp are not electrically commoned. Instead, each fluorescent lamp terminal


17


in one lampholder


51


of the lampholder connector


50


is connected to corresponding terminals


17


having the same relative position in the other lampholder


51


. In other words, terminals on the right side of each lampholder are electrically connected together and terminals on the left side of each lampholder are electrically connected together, but right-side terminals are not electrically connected to left-side terminals. It should be understood, however, that all of the terminals


17


for the two-lamp version


50


could be connected to a single bus in the same manner as for the three-lamp lampholder connector


150


because the ballast need not be connected directly to an individual pin on lamps connected to the lampholder connectors.




The use of integrally molded lampholders


51


simplifies the assembly of the lampholder connectors


50


which are assembled in much the same manner as the lampholder connectors


150


. Terminals


17


previously connected to wires can be inserted into lampholder terminal cavities on the lower surface


53


in the same manner as for the ballast lampholder cover


8


. The use of splicing terminals with the three-lamp lampholder connector


150


has been previously discussed.




Although the use of integrally molded lampholders greatly simplifies assembly of both the ballast lampholder subassemblies and the lampholder connectors, it should be understood that some, though not all, of this improvement can be achieved by attaching separately molded lampholders to a molded cover or to the lampholder connector base. Although this variation adds an assembly step, it still uses the same basic approach to achieve the other advantages of this invention. This is but one of the minor changes that can be resorted to without departing from the scope of the invention defined by the following claims.



Claims
  • 1. A lighting assembly for use in mounting a plurality of fluorescent lamps comprising:a ballast lampholder subassembly located at a first end of the lighting assembly, including a ballast lampholder housing with ballast circuitry mounted within the ballast lampholder housing connected to terminals in lampholders extending from the housing; at least one lampholder connector mounted on a second end of the lighting assembly, the lampholder connector including spaced-apart lampholders extending from a lampholder connector base with lampholder terminals in at least two of the lampholders being connected by lead wires extending through the lampholder connector base; wherein the lampholders of the ballast lampholder subassembly and the lampholder connector comprise integrally molded extensions of the ballast lampholder housing and the lampholder connector base, respectively.
  • 2. The lighting assembly of claim 1 wherein the ballast lampholder housing comprises a molded cover attached to a ballast lampholder base, and the lampholders of the ballast lampholder housing comprise molded extensions of the molded cover.
  • 3. The lighting assembly of claim 2 wherein the lampholders of the ballast lampholder housing include terminal cavities which open to an interior of the housing so that the terminals can be inserted into the lampholders through the openings.
  • 4. The lighting assembly of claim 2 wherein the ballast lampholder base comprises a metal plate attached to the ballast lampholder housing cover.
  • 5. The lighting assembly of claim 4 wherein the ballast circuitry is mounted on a circuit board positioned on the ballast lampholder base.
  • 6. The lighting assembly of claim 5 further comprising lead wires electrically connecting the terminals to the circuit board.
  • 7. The lighting assembly of claim 2 wherein the molded cover includes protruding sections separated by channels, and the lampholders are located in the channels.
  • 8. The lighting assembly of claim 1 wherein the lampholders of the lampholder connector include terminal cavities which are open to a lower surface of the lampholder connector base, the terminals are disposed in the cavities, and the terminals are connected by lead wires which extend along the lower surface of the lampholder connector base.
  • 9. The lighting assembly of claim 1 wherein the ballast lampholder subassembly and the lampholder connector are mounted at opposite ends of a fluorescent lighting troffer.
  • 10. The lighting assembly of claim 9 wherein the ballast lampholder subassembly and the lampholder connector are separate with each attached only to the fluorescent lighting troffer and to fluorescent lamps extending therebetween.
  • 11. A ballast lampholder subassembly for use in a fluorescent lighting fixture comprising:a molded ballast lampholder cover with lampholders extending from the ballast lampholder cover, each of the lampholders including a pair of terminal cavities opening to an interior surface of the ballast lampholder cover; fluorescent lamp terminals insertable into the terminal cavities after first ends of wire leads have been terminated to the fluorescent lamp terminals; a circuit board with ballast circuitry and ballast components mounted on the circuit board, second ends of the wire leads being attached to the circuit board; and a ballast lampholder base attached to the ballast lampholder cover to form a ballast lampholder housing, the circuit board and the wire leads which connect the fluorescent lamp terminals to the ballast circuitry and to the ballast components being positioned within the ballast lampholder housing.
  • 12. The ballast lampholder subassembly of claim 11 wherein the lampholders comprise molded extensions of the molded ballast lampholder cover.
  • 13. The ballast lampholder subassembly of claim 12 wherein the molded ballast lampholder cover encloses three sides of the ballast lampholder housing and the ballast lampholder base encloses a fourth side of the ballast lampholder housing.
  • 14. The ballast lampholder subassembly of claim 13 wherein the ballast lampholder base comprises a metal plate.
  • 15. The ballast lampholder subassembly of claim 14 wherein the ballast lampholder cover is snapped to the metal plate.
  • 16. The ballast lampholder subassembly of claim 14 wherein the circuit board is mounted on an interior surface of the ballast lampholder base.
  • 17. The ballast lampholder subassembly of claim 13 wherein the molded ballast lampholder cover includes multiple enclosure sections separated by channels having a smaller volume than the enclosure sections, the molded lampholders extending from the channels with the enclosure sections providing space for housing ballast components.
  • 18. The ballast lampholder subassembly of claim 17 wherein the lampholders are equally spaced-apart between opposite ends of the ballast lampholder housing.
  • 19. The ballast lampholder subassembly of claim 17 wherein the ballast lampholder cover includes a mounting pocket for supporting a splicing terminal for connecting power leads to the printed circuit board.
  • 20. A method of assembling a ballast subassembly for use in a lighting fixture comprising the steps of:terminating insulated wire leads to terminals; inserting the terminals into lampholders molded as part of a ballast lampholder housing cover with the insulated wire leads extending from the terminals; connecting opposite ends of the wire leads to a circuit board containing ballast circuitry and ballast components; positioning the circuit board between a ballast lampholder housing base and the ballast lampholder housing cover; and attaching the ballast lampholder housing base to the ballast lampholder housing cover to form a ballast lampholder housing which encloses the circuit board and the wire leads.
CROSS-REFERENCE TO RELATED APPLICATIONS

This application is being filed concurrently with U.S. patent application Ser. No. 09/158,195, now U.S. Pat. No 6,048,220, issued Apr. 11, 2000 both of which claim the benefit of U.S. Provisional Application No. 60/060,661, filed Oct. 2, 1997, and have the same assignee.

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Provisional Applications (1)
Number Date Country
60/060661 Oct 1997 US