Abstract:
A lighted sign display assembly includes a housing a lens aperture formed at a base end of the housing. The lens aperture secures a lens to the housing within the lens aperture, and the lens has areas that are formed to convey visual information. A lens removal aperture is formed near the base end of the housing to receive an object that applies a force to the lens to remove the lens from the aperture. At least one mounting projection is formed near the base end of the housing, each mounting projection receiving a mounting device to secure the display assembly to a desired object. An illumination assembly is secured in an aperture formed at an end of the housing opposite the lens aperture. The housing includes a temperature aperture formed to provide ventilation to dissipate heat generated by the illumination assembly. A reflective coating covers the interior surface of the housing, with the reflective coating reflecting light generated by the illumination assembly towards the lens. The housing may be ellipsoid-shaped, and the illumination assembly may include a power adapter coupled to the running lights or cigarette lighter of a vehicle to thereby apply electrical energy to the illumination assembly.

Description:
This application claims benefit of provisional application Ser. No. 60/118,835 filed Feb. 5, 1999. 
    
    
     TECHNICAL FIELD 
     The present invention relates generally to electronic signs, and more specifically to a portable electronic sign for use in vehicles. 
     BACKGROUND OF THE INVENTION 
     Electronic signs are ubiquitous in society today and are utilized to convey countless types of visual information. For example, electronic signs are placed in store windows to indicate whether a store is open or closed or to advertise a particular product. Many such signs utilize neon bulbs formed in the shape of the desired message, such as a product name, and require AC power for illumination. The requirement for AC power makes the use of such signs difficult in situations where only DC power is available, such as in vehicles like cars and trucks. In addition, such signs may not be used in applications where the message being displayed needs to be changed. Another type of electronic sign is known as a backlit sign. In a backlit sign, a face plate or lens is formed having the desired message to be displayed, and a lens is placed in a housing having a light bulb which then illuminates the lens to thereby display the desired message. Such a backlit sign may be powered using either AC or DC power. While DC power may be utilized, in many instances the resulting illumination intensity is inadequate to display the desired message. In many situations, a backlit sign is utilized where it is desirable to be able to conveniently change the message displayed. For example, the sign may display prices that need to be periodically updated. In such applications, the lens must be capable of being easily removed from a housing so that the displayed message may be conveniently changed. 
     There is the need for a portable backlit electronic sign that provides relatively high intensity illumination and is also capable of displaying a variety of messages with relative ease. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the present invention, a lighted sign display assembly includes a housing having an interior surface and an exterior surface. The housing includes a lens aperture formed at a base end of the housing. The lens aperture is adapted to secure a lens to the housing within the lens aperture, and the lens has areas that are formed to convey visual information. A lens removal aperture is formed near the base end of the housing. The lens removal aperture is adapted to receive an object that applies a force to the lens to thereby assist in removing the lens from the aperture. At least one mounting projection is formed near the base end of the housing. The mounting projection is adapted to receive a mounting device to secure the display assembly to a desired object. An illumination aperture is formed at an end of the housing opposite the lens aperture, and is adapted to secure an illumination assembly to the housing within the illumination aperture. 
     The lighted sign display assembly further includes at least one temperature aperture, with each temperature aperture being formed to allow heat generated by the illumination assembly to be transferred from the interior surface side of the housing to the exterior surface side. A reflective coating covers at least some of the interior surface of the housing, with the reflective coating reflecting light generated by the illumination assembly towards the lens. An illumination assembly is secured in the illumination aperture, and receives electrical energy and generates optical energy from the electrical energy. 
     According to further aspects of the present invention, the housing is an ellipsoid-shaped housing and the illumination assembly includes a power adapter that is coupled to the running lights of a vehicle to thereby apply electrical energy to the illumination assembly. The power adapter may also be adapted to be plugged into a cigarette lighter of a vehicle to supply electrical power. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded isometric view of a lighted sign display assembly according to one embodiment of the present invention. 
     FIG. 2 is an isometric view of the assembled lighted sign display assembly of FIG.  1 . 
     FIG. 3 is a rear isometric view of the display housing of FIGS. 1 and 2. 
     FIG. 4 is aside view of the assembled lighted sign display assembly of FIG.  2 . 
     FIG. 5 is a top view of the assembled lighted sign display assembly of FIG.  2 . 
     FIG. 6 is an exploded isometric view of a lighted sign display having an ellipsoid-shaped housing and lens according to another embodiment of the present invention. 
     FIG. 7 is a front view of the ellipsoid-shaped housing of FIG.  6 . 
     FIG. 8 is a bottom view of the ellipsoid-shaped housing of FIG.  6 . 
     FIG. 9 is a side view of the ellipsoid-shaped housing of FIG.  6 . 
     FIG. 10 is an exploded view illustrating the lens-retaining projection of FIG.  9 . 
     FIG. 11 is an exploded side view of the pry slot  612  of FIG.  6 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 is an exploded isometric view of a lighted sign display  2  including a housing  4  and lens  6  according to one embodiment of the present invention. When the lighted sign display  2  is assembled, a desired message  8  on the lens  6  is illuminated to thereby display the message, as will be explained in more detail below. In the embodiment of FIG. 1, the housing  4  includes a rounded body  10  having a rectangular aperture  12  formed at a front end of the body and a front panel  14  integrally attached to the body  10  around the aperture  12 . The body  10  and front panel  14  are typically formed from a high-heat plastic, but may also be formed from other suitable materials. The lens  6  is also typically formed from a suitable translucent plastic with the message  8  similarly being a translucent material either attached to the lens or silk screened onto the lens. 
     A mounting hole  16  is formed at a rear end of the rounded body  10 , and a light fixture  18  is secured in the mounting hole. The light fixture  18  includes a socket in which a bulb  20  is placed, and further includes electric terminals (not shown) that supply electric power to the bulb  20 . A power cable  22  has a first end connected to the electric terminals of the light fixture  18 , and has a second end connected to a power adapter  24 . The power adapter  24  receives power from an external source (not shown), and this power is applied through the cable  22  to illuminate the bulb  20  in the light fixture  18 . A reflective coating  21  may be applied on the interior of the body  10  to reflect light generated by the bulb  20  toward the aperture  12 . The power adapter  24  may be a cigarette lighter adapter for receiving power from a cigarette lighter socket in a vehicle, or a running lights adapter having clips that may be attached to the running lights of a vehicle to receive power, and may be any type of adapter suitable for connection to other the source of power being used to illuminate the bulb  20 . 
     The body  10  further includes a plurality of ventilation holes  26  that allow circulation of air in the body  10  to remove heat generated by the bulb  20 . The illustrated ventilation holes  26  are formed on the bottom of the body  10 , but identical ventilation holes  26  (not shown) are formed on the top of the body  10 . The ventilation holes  26  may also be formed on the sides of the rounded body  10  to provide for better air circulation, may only be formed on top, or may be omitted in some applications where the body  10  and lens  6  are large enough to sufficiently dissipate the heat generated by the bulb  20 , as will be understood by those skilled in the art. 
     In the housing  4 , the front panel  14  includes a plurality of notches  28 , with each notch in the housing  4  having a corresponding notch in the lens  6 . A rubber band  30  or other suitable device fits into the notches  28  to secure a lens  6  to the front panel  14  of the housing  4 . The front panel  14  further includes two mounting holes  32  and  34 , each of these mounting holes having a corresponding mounting hole  36  and  38 , respectively, in the lens  6 . Two suction cups  40  and  42  fit into the holes  32 ,  36  and  34 ,  38 , respectively, and secure the sign display  2  to a display surface, such as a vehicle window. Other suitable components can be used in place of the suction cups  40 ,  42 , such as screws or even adhesive on the front of the front panel  14 . 
     To assemble the lighted sign display  2 , the power cable  22  is connected to the light fixture  18  and power adapter  24 , and the light fixture  18  is thereafter placed in position in the mounting hole  16 . The bulb  20  is then placed in the light fixture  18 , and the lens  6  is secured in place against the front panel  14  by placing rubber bands  30  in the notches  28  formed on the lens  6  and front panel  14 . Once the lens  6  has been secured in place against the front panel  14 , the suction cups  40  and  42  are placed in holes  32 ,  36 , and  34 ,  38 , respectively. The precise order in which the components  4 - 42  are assembled to form the display  2  may vary, as will be understood by those skilled in the art. FIG. 2 is an isometric view of the assembled lighted sign display  2 . In FIG. 2, the rubber bands  30  have been omitted merely for ease of illustration and, of course, would be secured in position in the notches  28 . Once the display  2  has been assembled, it is placed in its desired display location by securing the suction cups  40 ,  42  to a suitable smooth surface, such as a vehicle window. The power adapter  24  is then connected to the appropriate power source, such as the vehicle running lights or cigarette lighter. When power is applied to power adapter  24 , this power is applied through the cable  22  to the bulb  20  which, in turn, illuminates the lens  6  to thereby display the message  8 . 
     FIGS. 3-5 are various views of the lighted sign display  2  of FIGS. 1 and 2 that better illustrate the shape of the body  10 . FIG. 3 is a rear isometric view of the display  2  illustrating the shape of the body  10 . In the embodiment of FIG. 3, the body  10  includes first and second angled side walls  300 ,  302 . The ventilation holes  26  are shown on top of the body  10 . FIG. 4 is a side view and FIG. 5 is a top view of the display  2  further illustrating the shape of the housing  4 . 
     FIG. 6 is an exploded isometric view of a lighted sign display  600  having an ellipsoid-shaped housing  602  and elliptical lens  604  according to another embodiment of the present invention. The display  600  includes components  606 - 620 , each of which a corresponding component in the display  2  of FIG.  1  and thus, for the sake of brevity, these components will not again be described in detail. The housing  602  includes a lens aperture  622  formed at a front of the housing, and a illumination aperture  624  formed at a rear of the housing. An inner lens retaining projection  626  is formed around the perimeter of the aperture  622  at the front of the housing  600 , along with two outer lens retaining projections  628  and  630  (see FIG. 7) formed along the bottom and top, respectively, of the elliptical front-end of the housing  602 . The elliptical lens  604  is secured in place between the inner lens retaining projection  626  and outer lens retaining projections  628 ,  630 , as will be described in more detail below. The housing  602  further includes two pry slots  632 ,  634  formed in the walls of the housing  602 . The front of the pry slots  633 ,  634  are apertures in the surface of the inner lens retaining projection  626  as shown. The pry slots  632 ,  634  are formed to allow an object, such as a screwdriver, to be inserted into one or both of the slots to apply a force to the elliptical lens  604  to thereby remove the elliptical lens from between the inner retaining projection  626  and outer retaining projections  628 ,  630 . Although two slots  632 ,  634  are shown in the embodiment of FIG. 6, the number may vary with there being one slot or no slots in alternative embodiments. Two mounting projections  636 ,  638  are formed at the front of the housing  602 , each of the mounting projections  636  and  638  including a slot to receive the suction cups  618  and  616 , respectively, to secure the housing  600  in place during operation, as previously described. A reflective coating  617  is applied to the interior surface of the housing  600  to reflect optical energy generated by the bulb  612  towards the front of the housing  602 . Typically, the reflective coating  617  is applied after the aperture  624  and holes  610  have been formed, but may also alternatively applied before formation of these components, as will be appreciated by those skilled in the art. The housing  602  includes the ventilation holes  610  formed in the top of the housing, and may also include ventilation holes formed at other locations on the housing. The housing  602  may not need such ventilation holes  610  in some embodiments where the housing  602  and lens  604  can adequately dissipate the heat from the bulb  612 . 
     FIGS. 7-9 are various views that further illustrate the structure of the housing  602  of FIG.  6 . FIG. 7 is a front view of the housing  602  that better illustrates the top outer lens retaining projection  630  and formation of the apertures of the pry slots  632 ,  634  in the inner lens retaining projection  626 . In the embodiment of FIG. 7, the outer lens retaining projections  628 ,  630  extend along top and bottom portion of the aperture  622 , but the number and location of these projections may vary, as will be appreciated by those skilled in the art. The housing  602  made from a high-heat plastic or other suitable material, and may be formed through injection molding or other suitable processes. 
     FIG. 8 is a bottom view and FIG. 9 is a side view of the ellipsoid-shaped housing  600  which better illustrate the depth of the housing  600  and structure of the lens retaining projections  626  and  630 . In FIG. 8, the elliptical lens  604  (not shown) fits in the space  700  between the outer lens retaining projection  630  and the inner lens retaining projection  626 . In FIG. 9, the bottom of the elliptical lens  604  fits in the space  800  between the outer lens retaining projection  628  and the inner lens retaining projection  626 , and the top of the elliptical lens  604  fits in the space  802  between the outer lens retaining projection  630  and the inner lens retaining projection  626 . 
     FIG. 10 is an exploded view better illustrating the position of the elliptical lens  604  in place between the inner lens retaining projection  626  and the outer lens retaining projection  628 . To mount the lens  604  in position between the projections  626  and  628 , the lens is pushed inward as indicated by an arrow  902 . As the lens  604  is pushed inward, the lens makes contact with a front angled surface  904  of the outer lens retaining projection  628 . The relatively rigid lens  604  applies an outward force indicated by an arrow  906  as the lens is pushed inward along the direction  902 . The housing  602  outwardly flexes in the direction  906  in response to the outward force from the lens  604  until the lens is pushed beyond a peak  908  of the outer lens retaining projection  628 . Once the lens  604  is pushed beyond the peak  908 , the housing  602  begins to inwardly flex so that the projection  606  moves in front of the lens  604  to thereby secure the lens in position a shown in FIG.  10 . 
     FIG. 11 is an exploded side view of the pry slot  634  of FIG.  6 . The pry slot  634  extends from and outer surface  1000  of the housing  602  to the front surface  1002  of the inner lens retaining projection  626 . The elliptical lens  604  is shown secured in place against the front edge of the inner lens retaining projection  626 . To remove the lens  604 , a screwdriver or other suitable object is inserted into the pry slot  634  to apply a force F to the lens  604 . In response to the force F, the lens  604  moves outwardly towards the front of the housing  602  and once the lens  900  is beyond the peak  908  of the outer lens retaining projection  628  (see FIG. 10) the lens  604  may be removed from housing. 
     One skilled in the art will appreciate various changes may be made to the lighted sign displays  2  and  600 . For example, the reflective coatings  21  and  617  may be omitted and the respective lenses  6  and  604  may be formed of a suitable optically diffusing material such as white plastic, or the lenses may be coated on one side with optical diffusing material, such as white ink, to diffuse optical energy incident on the lenses and eliminate the need for the reflective coatings. Such optically diffusing material may be applied as a plurality of layers, and may be applied to the same side of the lens  6 ,  604  as the message  8 ,  614 , respectively, or may be applied to the opposite side of the lens. 
     It is to be understood that even though various embodiments and advantages of the present invention have been set forth in the foregoing description, the above disclosure is illustrative only, and changes may be made in detail, and yet remain within the broad principles of the invention. Therefore, the present invention is to be limited only by the appended claims.