Abstract:
The interior of a mailbox is illuminated with a highly efficient LED lamp powered by a rechargeable battery. The LED lamp is turned on when the mailbox door is opened. A solar panel is mounted under a light-transmitting cover located on the roof of the mailbox for recharging the battery. The illumination system is for the most part composed of a pair of compact modular assemblies which are carried by the mailbox.

Description:
CROSS REFERENCE TO RELATED APPLICATION  
       [0001]     This application claims priority benefits from U.S. Provisional Application No. 60/686,566 filed Jun. 2, 2005, “INTERNALLY LIGHTED MAILBOX”. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates in general to internally illuminated mailboxes and in particular to solar-powered switch-operated light-emitting-diode (LED) illuminated mailboxes.  
         [0004]     2. Description of Prior Developments  
         [0005]     Mailboxes have been provided with both internal and external lighting, typically using conventional light bulbs. However, when batteries are used as a power source, conventional incandescent lighting quickly draws down the battery charge. This can cause a problem if the battery is charged by solar cells which require prolonged periods of sunlight to provide an adequate charge to the battery.  
         [0006]     Accordingly, a need exist for a mailbox illuminated with the convenience of solar power, yet which can provide continuous illumination for up to 24 hours with a single charging, even in areas where sunlight is intermittent.  
       SUMMARY OF THE INVENTION  
       [0007]     The present invention has been developed to meet the needs noted above by providing a mailbox with a solar powered LED light source which can illuminate the interior of a mailbox for periods up to 24 hours with a single charge from a conventional solar cell panel. By using one or more LED&#39;s as a light source, the draw on an electric storage battery can be minimized, and the period of illumination can be maximized.  
         [0008]     In one embodiment, a solar panel, electronic circuitry, rechargeable battery and LED lighting are arranged in a compact assembly to minimize the space required within the interior of a mailbox so as to maximize the room available for mail. The illumination provided by the LED is controlled by a microswitch which coacts with the mailbox door so as to provide illumination only when the door is opened. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]     In the drawings:  
         [0010]      FIG. 1  is a top right perspective view of a mailbox constructed in accordance with the present invention;  
         [0011]      FIG. 2  is a partial front perspective view of the mailbox of  FIG. 1 , with the door open and showing the interior of the mailbox;  
         [0012]      FIG. 3  is a partial top view of an aperture or mounting hole formed in the roof of the mailbox and showing the formation of mounting tabs under the aperture;  
         [0013]      FIG. 4  is a partial exploded view of the modular subassemblies of the lighting system positioned for mounting in the roof of the mailbox;  
         [0014]      FIG. 5  is an enlarged view in section taken along section line  5 - 5  of  FIG. 1 ;  
         [0015]      FIG. 6  is a side view of the modular battery assembly;  
         [0016]      FIG. 7  is a top view of  FIG. 6 ;  
         [0017]      FIG. 8  is a partial view of a door-actuated switch for controlling the illumination within the mailbox;  
         [0018]      FIG. 9  is a schematic circuit of the lighting system used to illuminate the interior of the mailbox;  
         [0019]      FIG. 10  is a detailed circuit diagram adapted for use with the lighting system of the present invention;  
         [0020]      FIG. 11  is a schematic circuit similar to that of  FIG. 9 , showing the use of a lighting strip of surface mounted LED&#39;s.  
         [0021]      FIG. 12  is a partial view in longitudinal section taken through the central portion of the roof of the mailbox in accordance with another embodiment of the invention;  
         [0022]      FIG. 13  is a partial perspective view of another embodiment of the invention showing a modular, unitary, self-contained lighting assembly; and  
         [0023]      FIG. 14  is a view in section of the modular lighting assembly of  FIG. 13 .  
     
    
       [0024]     In the various views of the drawings, like reference numbers designate like or similar parts.  
       DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0025]     The present invention will now be described in conjunction with the drawings, beginning with  FIGS. 1 and 2  which show a mailbox  10  constructed in accordance with the present invention. Mailbox  10  has a body  12  which includes a pair of sidewalls  14  ( FIG. 2 ), a floor  16 , an arched roof  18 , a front door  20 , and a rear wall  22 .  
         [0026]     The sidewalls  14  and roof  18  may be formed of a single sheet of metal or plastic or other suitable material. In one embodiment, the roof  18  and sidewalls  14  are formed of a single thin sheet of aluminum. The floor  16 , also advantageously formed of an aluminum sheet, is staked, crimped or otherwise attached to the bottom perimeter of the sidewalls  14 . The front door  20 , likewise formed of an aluminum sheet, is pivotally attached to the bottom front portion of sidewalls  14  by a pair of rivets or pins  24 .  
         [0027]     The rear wall  22 , also formed of an aluminum sheet, is crimped around its perimeter to the rear edge of the roof  18  and sidewalls  14  along a crimped or rolled over joint  25 . A flag  26  is pivotally connected to the sidewall  14  by a crimped pin, blind rivet, nut and bolt or other shaft-like connector  28 . The entire body  12  is mounted on a mast or post  30  in a known fashion, such as by nails or screws  31  ( FIG. 2 ).  
         [0028]     A resilient over-center snap-fit retainer  32  is pinned or otherwise fixed to the top front of the roof  18  and door  20 . A looped plastic handle  34  is fixed to the top center of the door  20  to provide both a finger grip and retainer for opening and retaining the door in the respective positions shown in  FIGS. 2 and 1 . A cantilevered plastic leaf spring retainer  36  is fixed to the top front center of roof  18  to resiliently hold and release the top arched portion of the handle  34 .  
         [0029]     Up to this point, the construction of mailbox  10  is generally of a conventional design. The invention is primarily directed to a lighting and control system for illuminating the interior of the mailbox body  12  with a highly efficient, compact and unobtrusive solar-powered battery-operated light emitting diode (LED).  
         [0030]     A particular advantage of the subject lighting system is the use of inexpensive, commercially available “off-the-shelf” components which results in a simple and economical construction. Moreover, because of the use of rechargeable batteries in combination with a solar cell battery recharger and LED illumination, the lighting system can operate without maintenance for months or years at a time. Virtually no set-up is required.  
         [0031]     As further seen in  FIGS. 1 and 2 , a modular lighting system  40 , which includes a solar panel assembly and a battery assembly, is mounted on the top central rear portion of roof  18 . As best seen in  FIGS. 3 and 4 , an aperture or cut out portion  42  is formed in roof  18  to receive the lighting system  40 . Aperture  42  is shown as a rectangular or square opening, but any suitably shaped opening may be used. A rubber gasket  44  is adhesively bonded or otherwise positioned around the aperture  42 .  
         [0032]     As further shown in  FIGS. 3 and 4 , two sets of four stepped mounting tabs  46 ,  48  are formed, such as by a punching operation, from the sheet material of roof  18 . The first or inner set of four tabs  46  is located between the second or outer set of mounting tabs  48  and, as seen in  FIG. 4 , extend further downwardly into the interior  50  of body  12  than the outer set of mounting tabs  48 .  
         [0033]     A solar cell or solar panel assembly  52  is mounted within the aperture  42  as shown in  FIGS. 1 and 5 . Threaded fasteners such as screws  54  engage bores  56  ( FIG. 3 ) in the outer set of mounting tabs  48  and clamp the solar panel assembly  52  to the roof  18  of mailbox  10 . A perimeter flange  57  on solar panel assembly  52  engages and tightly compresses the perimeter gasket  44  against roof  18  to form a water-tight seal.  
         [0034]     Prior to mounting the solar panel assembly  52  to the mailbox  10 , a battery assembly or module  60  ( FIGS. 6 and 7 ) is mounted to the inner set of mounting tabs  46 . As seen in  FIG. 7 , battery assembly  60  includes a plastic casing or housing  62 , having a rectangular sidewall  64  extending upwardly from a planar plastic base  66 .  
         [0035]     Four mounting tabs  68  extend outwardly, one from each corner of the battery assembly  60 . Each mounting tab  68  is formed with a mounting hole  72  and dimensioned to concentrically register with each respective mounting hole in each inner mounting tab  46  on roof  18 . As seen in  FIG. 5 , threaded fasteners  74  fix the battery assembly  60  to the mounting tabs  46 , and symmetrically position the battery assembly  60  directly beneath the solar panel assembly  52 .  
         [0036]     As further seen in  FIGS. 5, 6  and  7 , a hole or passage  78  is formed through the base  66  of housing  62  to allow for the passage of a pair of electrical power leads from a rechargeable battery  80  to one or more light sources  82 , such as a small incandescent bulb, or preferably one or more LED&#39;s. LED&#39;s are preferred because of their relatively low power demand and relatively high visible light output. The LED  82  can be adhesively bonded to the base  66 .  
         [0037]     Battery  80  can be any type of rechargeable battery, such as nickel-cadmium or lithium ion battery. In the cases of a nickel-cadmium battery powering a conventional LED light source, a single day&#39;s solar charging of the battery will provide up to 24 continuous hours of illumination from the LED. This is obviously advantageous in those areas where sunlight is infrequent or intermittent, as a few hours of stored battery charge can provide weeks or months of intermittent LED illumination, depending on how often the mailbox  10  is opened, as discussed below.  
         [0038]     Returning to  FIG. 5 , it is seen that the solar panel assembly  52  includes an arched or domed cover  84 , formed of a light transmitting material such as clear plastic or clear glass. As shown in the embodiment of  FIG. 5 , cover  84  is molded from clear plastic with an arched contour substantially matching the arched contour of roof  18  and includes a downwardly depending rectangular side wall  86 . A rectangular ledge  88  extends horizontally inwardly from side wall  86  to serve as a mounting platform for a solar cell panel  90 . Panel  90  may be held in position on ledge  88  with an adhesive bond or with conventional clips or fasteners.  
         [0039]     Solar cell panel  90  is of known construction and can be commonly found in such devices as solar powered outdoor landscape lighting. Panel  90  is electrically connected to a battery charging circuit board  92  ( FIG. 7 ) mounted in housing  62  of the battery assembly or module  60 . The charging circuit  91  on circuit board  92  is also of known design, and can be substantially the same as that found on outdoor solar-powered landscape lights.  
         [0040]     Charging power from the charging circuit board  92  is transmitted to one or more rechargeable batteries  80  mounted in the housing  62  between a pair of contacts  96  ( FIG. 5 ) and biased by a spring  92 . Battery  80  ( FIG. 5 ) is electrically connected via contacts  96  to the light source or LED  82 . A switch, such as a microswitch  100  ( FIGS. 1, 2  and  8 ), is located in the circuit&#39;s electrical leads between the battery  80  and LED  82  as discussed below.  
         [0041]     Switch  100  is mounted on the front interior portion of one side wall  14  with a bracket  104  using a fastener such as a screw  106  ( FIG. 8 ). Bracket  104  may be riveted to side wall  14 . Switch  100  includes a conventional cantilevered spring arm or spring plunger  108  which is aligned with a switch actuator  110  fixed to the inner wall of the door  20 . Actuator  110  can be any type of projection or abutment, such as a formed metal strip fixed to door  20  by rivets.  
         [0042]     When door  20  is closed, actuator  110  engages and depresses arm  108  and opens the circuit between battery  80  and LED  82 . This prevents battery  80  from powering LED  82  and thus turns off LED  82 . When door  20  is opened, arm  108  is released. This closes the contacts and completes the circuit in microswitch  100  and causes power to flow from battery  80  to LED  82  via wires  112  ( FIG. 8 ) and thereby illuminate the interior  50  of mailbox  10  only when door  20  is opened.  
         [0043]     This switching arrangement conserves the charge in battery  80  and ensures reliable illumination of the interior  50  of mailbox  10  over extended periods of time. A schematic circuit of the lighting system  40  is shown in  FIG. 9 . Solar panel  90  receives ambient light, converts it to electricity and transmits electric power to the charging circuit board  92  via electrical leads  114  ( FIG. 2 ). The charging circuit on circuit board  92  transmits charging voltage to battery  80  via electrical leads  116 . As indicated above, battery  80  selectively powers and illuminates LED lamp  82  via switched electrical leads  112 . A more detailed circuit diagram of a charging circuit  91  adapted for use with the present invention is shown in  FIG. 10 .  
         [0044]     As best seen in  FIGS. 1 and 5 , an advantage of the present invention is the extremely compact arrangement of lighting system  40 . By forming the cover  84  of solar panel  90  as an extension of and virtually flush with roof  18 , the general appearance of mailbox  10  resembles that of conventional non-illuminated mailboxes.  
         [0045]     Moreover, by vertically nesting the battery assembly  60  within the lower portion of the solar panel assembly  52 , very little space is taken up within the interior  50  of mailbox  10 , so as to minimize any interference or contact with mail. This also protects the lighting system  40  from damage and maximizes the room for mail. As seen in  FIG. 5 , a cover plate  120  is fitted on top of the battery assembly  60  to cover the circuit board  92  and battery  80 . The battery assembly  60  is positioned directly against the underside of the solar panel assembly  52  and positioned and snugged against it via the positioning of the mounting tabs  46 ,  48 . This provides an extremely compact lighting system.  
         [0046]     Another highly compact and space-saving embodiment of the invention is shown in  FIGS. 11 and 12  wherein the light sources  82  are in the form of a series of evenly spaced apart LEDs  82  mounted longitudinally along an elongated mounting strip or circuit board  124 . The LEDs  82  can be mounted to circuit board  124  using conventional “though-hole” mounting techniques. In this case, electrical leads from each LED are inserted into holes formed through the circuit board  124  and soldered to a circuit including leads  112  provided on board  124 .  
         [0047]     An even more compact and space-saving arrangement can be achieved by using surface mounted technology (SMT) to mount the LEDs  82  to the surface of board  124  without the need for any through-holes formed in circuit board  124 . The electrical components of the charging circuit  91  can also be mounted to circuit board  124  using surface mount technology and surface mounted components.  
         [0048]     While only one LED  82  need be used, by using a series of spaced-apart LED&#39;s extending from front-to rear along the roof  18  of mailbox  10 , superior illumination is provided to every area within the interior  50  of the mailbox body  12 . As seen in  FIG. 12 , circuit board  124  can be mounted to body  12  by bonding, such as by adhesive beads  125 . Double sided adhesive tape, threaded fasteners or even releasable hook and loop fabric connector strips can also be used for this mounting purpose.  
         [0049]     As further shown in  FIGS. 11 and 12 , rechargeable battery  80  can take the form of one or more small disk-shaped batteries of the type used in wrist watches and other small electrical appliances. These small batteries further reduce the space taken up inside the mailbox interior  50  so as to avoid contact with envelopes and other mail placed in mailbox  10 .  
         [0050]     Another embodiment of the invention is shown in  FIGS. 13 and 14  wherein a modular self-contained lighting assembly  126  is shown disposed over the roof  18  of mailbox  10 . An opening, cut out or aperture receives the module  126 .  
         [0051]     As seen in  FIG. 14 , module  126  can be formed as a hollow, watertight plastic compartment having a thin, low unobtrusive profile. A roof or upper shell  130  can be adhesively bonded to a floor or lower shell  132  to form module  126 . Each shell  130 ,  132  can be formed at least in part of a clear light-transmitting plastic material to allow solar cell panel  90  to receive sunlight and to allow light sources  82  to transmit light into the interior  50  of mailbox  10 .  
         [0052]     Module  126  can be mounted to virtually any apertured portion of mailbox  10 , except perhaps the bottom or floor  16 , which would not likely receive sufficient sunlight to charge the solar cell panel  90 . Virtually any type of mounting may be used to mount module  126  to mailbox  10 , including adhesives, threaded fasteners, brackets, and press fits. In the example shown in  FIGS. 13 and 14 , integral snap-fit spring hooks  134  are molded homogeneously with the lower shell  132  to allow for a simple snap-fit mounting of module  126  to mailbox  10 .  
         [0053]     Module  126  houses and encloses the solar panel  90 , charging circuit  91 , battery  80  and light source(s)  82 . The thin flat circuit board  126  of  FIG. 11  is well suited for use with module  126 , as it can be produced with a very low profile.  
         [0054]     Module  126 , as shown in  FIG. 13 , can be mounted during initial manufacture of mailbox  10 , or can be supplied as a stand-along retrofit unit. In this case, all that is required is the cutting of an aperture  128  in mailbox body  12  of an appropriate predetermined size that may be formed with a stencil provided with an after market module  126 . All that is required than is a simple snap-fit of module  126  into aperture  128 . A gasket  44  may be provided around the bottom periphery of bottom shell  132  to provide a watertight seal against the mailbox.  
         [0055]     A plunger rod  138  is connected to a microswitch  110  mounted inside module  126 . Plunger rod  138  can be cut to length to normally engage the rear face of handle  34  ( FIG. 1 ) and actuate microswitch  110 . When the mailbox door  20  is opened, plunger rod  138  moves forwardly to close microswitch  110  and illuminate the LED&#39;s  82 . When the door  20  is closed, microswitch  110  is opened.  
         [0056]     Of course, any other suitable switching arrangement can be used to actuate microswitch  110 , such as a proximity senor switch which can sense a user opening the mailbox. Plunger rod  138  can be eliminated in this case and, the proximity switch can be mounted in module  126  so that module  126  can be completely sealed and self-contained. Capacitance type proximity switches are commercial available for this application.  
         [0057]     There has been disclosed heretofore the best embodiment of the invention presently contemplated. However, it is to be understood that various changes and modifications may be made thereto without departing from the spirit of the invention.