Patent Abstract:
An illumination device comprising, in combination an elongated housing, at least two elongated lamps extending in the housing, one or two magnetic ballasts carried in the housing to selectively energize the lamp or lamps, and switch means carried by the housing to control energization of said one or two ballasts.

Full Description:
BACKGROUND OF THE INVENTION 
   This invention relates generally to portable illumination devices and more particularly to an improved device wherein a bulb or lamp, or lamps, are energized by magnetic ballast or ballasts. 
   There is need for improvements in portable illumination devices wherein complexity of electrical circuitry required for power supply to lamps is reduced, and wherein unreliability of such power supply is also reduced. There is also need for an improved device employing magnetic ballast or ballasts, as well as a device having improvements in structure and functions as will be seen. 
   SUMMARY OF THE INVENTION 
   It is a major object of the invention to provide for improvements in portable illumination devices as referred to. Basically, the device comprises: 
   a) an elongated housing, 
   b) at least two elongated lamps extending in the housing, 
   c) one or preferably two magnetic ballasts carried in the housing to selectively energize the lamps, 
   d) and switch means carried by the housing to control energization of said one or two ballasts. 
   As will be seen, the housing typically has a forward illumination portion, a rearward grip portion and an intermediate portion, and wherein the lamp or lamps are carried at said forward portion, one of said two magnetic ballasts is carried at said intermediate portion, and the other of said two ballasts is carried at said rearward portion, enhancing weight distribution and ease of handling. Magnetic ballasts are significant weight adding devices, and their separation adds to manual control. One ballast may control one lamp, and the other ballast may control a second lamp, whereby at least one lamp will remain energized by a ballast if the other ballast fails. The lamps are typically fluorescent. 
   Another object is to provide improved cushioning supports for the multiple, elongated, parallel lamps. 
   Yet another object comprises optimum positioning of two ballasts in separate housing sections for weight distribution, and for hand gripping close to the magnetic ballasts. In this regard, ballast edge locating elements are provided in the housing sections, and may be molded into plastic housing shell sections. 
   An added object is to locate the ballasts out of the reflected light transmission path or paths from the lamps, as will be seen. 
   These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following specification and drawings, in which: 

   
     DRAWING DESCRIPTION 
       FIG. 1  is an elevation view, in perspective, showing the front side of the illumination device; 
       FIG. 2  is a view like  FIG. 1 , but showing the rear side of the device; 
       FIG. 3  is an enlarged section taken on lines  3 — 3  of  FIG. 1 ; 
       FIG. 4  is a bottom plan view taken on lines  4 — 4  of  FIG. 2 ; 
       FIG. 5  is a frontal view, taken on line  5 — 5  of  FIG. 3 , and partly broken away to show interior construction; 
       FIG. 6  is a section taken on lines  6 — 6  of  FIG. 3 ; 
       FIG. 7  is a section taken on lines  7 — 7  of  FIG. 3 ; 
       FIG. 8  is an enlarged plan view showing the lamps terminal and socket assembly; 
       FIG. 9  is a view taken on lines  9 — 9  of FIG.  8 . 
   

   DETAILED DESCRIPTION 
   The preferred illumination device  10  includes an elongated housing  11  which may consist of two complementary molded plastic shell sections  11   a  and  11   b , each extending throughout the length of the housing. Screw fasteners  12  hold the sections together, as for example is indicated in  FIG. 7. A  screw  12  interconnects two posts  13  and  14  respectively molded in and to sections  11   a  and  11   b . The screw head is typically protectively received in a recess  13   a  of post  13 . Section edges  11   a ′ and  11   b ′ are held together as shown. Other means to interconnect the sections may be provided. 
   The two sections of the housing together define a housing forward illumination portion  11   c , a rearward grip portion  11   d , and an intermediate portion  11   e . At least two elongated lamps  15  are carried to extend endwise in the hollow interior  16  of the housing forward portion  11   c , and so as to face a window or lens  17  peripherally carried by the housing sections  11   a  and  11   b , as is also clear form FIG.  1  . Two such lamps  15  are shown in  FIG. 6 , each having two adjacent sections. For example, each lamp may be H-shaped or U-shaped, extending in parallel relation in a common plane, and substantially filling, widthwise, the interiors defined by the two housing sections, for maximum light transmission in the sideward direction indicated by arrow  18  in  FIG. 3 , and through lens  17 . A reflector  19  is provided at the sides of the lamps opposite the lens, and may consist of a reflecting paper or other material. 
   The lamps  15  have distal end portions  15   a  received in openings  20   a  in cushioning holder or holders  20  that endwise seat the lamps. Such holder or holders may consist of elastomeric material, such as rubber or molded plastic, carried by the housing forward portion as seen in FIG.  3 . Spikes  90  carried by holder  20  project toward end walls  91  of the housing, to position the holder and lamp ends, endwise. The opposite end portions  15   b  of the lamps are carried by a plug or plugs  21  as seen in  FIG. 8 , and have electrical terminal pins  15   c  projecting into electrical sockets  15   d  carried within elastomeric holder or holders  22 . Mounting holders or clips are shown at  23  in  FIG. 6 , there being two U-shaped holders or clips  23 , each carrying two of the lamp end portions, or their holders. Note in  FIG. 6  the web structure  24  formed in the housing interior and positioning the two holders or clips  23 , within  22 . Spikes  94  on  22  project toward housing wall  95  to position holder  22 . 
   Also provided are at least one, and preferably two magnetic ballasts carried in the housing to energize the lamp or lamps, which are typically fluorescent. Two such ballasts are shown, one indicated at  26  within the hollow interiors  27  of the housing sections at the intermediate portion  11   e  of the housing, and the other indicated at  28  within the hollow interiors  29  of the housing sections and inwardly of the rearward grip portion  11   d  of the housing for ease of handling. One ballast is shown as electrically connected to one lamp associated with one holder or clip  23 ; and the other ballast is shown as electrically connected to the other lamp associated with the other holder or clip  23 . See wiring at  26   a  and at  27   a . Each lamp is typically U-shaped, or H-shaped to assemble to holder or holders  20  and  22 . This enables power supply to both lamps, and if one ballast fails to operate for any reason, the other ballast remains operative to supply power to its associated lamp. 
   An ON-OFF switch  30  in series with an AC power supply line  31  controls ON-OFF power supply to the two ballasts. The cable or cord for line  31  is shown as connecting at  34  to the end  35  of the grip portion  1   d  of the housing. An auxiliary power receptacle  36  is also provided at the housing end  35  to supply power from line  31  to a plug that may be inserted into receptacle  36 , as for power supply to another similar illumination device, if desired, or to other equipment. A hook  40  is carried at the forward end of the device to hang or support the device, from other structure, as at a work place. 
   It will be noted that the two ballasts are separated, for weight distribution along the length of the device  10 , and for weight concentration toward the manual grip end of the device, facilitating case of transport and maneuver of the device. Ballast  26  is located within a domed interior  60  of the housing, covered by housing device  62 , vented at  63 . 
   Ballasts of the type shown are known, one example being Models 013 and 015, produced by Robertson Ballast Company, of Chicago, Ill. 
   In a typical example, the device incorporates two 13-watt lamps, which withstand heavy usage and frequent device drops. The lamps may provide 26 watts of light energy, which is equivalent to 120+ watts of incandescence, so that an entire large work area can be illuminated. The body or housing is made of the durable plastic material. The ratcheting or detent hanging hook directs light to where needed, and the heavy duty (for example 3 conductor) cord withstands all normal shop usage. The unique push button switch prevents accidental on/off operation when working, as it is located in a shallow V-shaped recess  68  defined by the housing. Housing portion  11   d  is angled at between about 5° and 15° relative to housing portion  11   c , thereby creating recess  68 . 
   One example of the above lamp or lamps is known as PL-13 size lamp.

Technology Classification (CPC): 5