Changeable digital display device
FIELD OF THE INVENTION 
     This invention relates to a digital display device and is particularly related to a manually changeable digital display device for displaying different numerals. 
     BACKGROUND OF THE INVENTION 
     At the present time, display devices which display numbers may require that the numbers be changed frequently or from time to time; for example, a bank window will display, in numbers, the current interest rates being paid on various types of deposits at various types of loans and mortgages. The rates may change weekly or even daily. In one type of commercially available display device, the numbers 0 through 9 are printed on a plastic roll and the roll is then rotated to expose, in a frame, the desired numbers. In another type of display a frame receives a flat card having printed thereon one of the numbers 1 through 9. 
     A similar type of flat card system is used in other locations where prices or rates change periodically; for example, the price displays used at gasoline stations, stores and by cigarette vendors. However, the cards are easily lost or damaged, and when they become damaged, they may not fit in their frames. When a gas station wishes to change its prices for &#34;regular leaded&#34;, &#34;unleaded&#34;, &#34;high-test unleaded&#34; and &#34;diesel&#34;, 12 separate numbers must be changed, which is time consuming and may be particularly difficult if the number cards are bent or misplaced. 
     It is therefore an object of this invention to provide a display device which may be readily and easily changed, by hand, in order to display the numerals 0 through 9; so that a row of such devices can show prices or rates, and may be rapidly changed to reflect the rapidly changing rates or prices. 
     It is a further object of the present invention to provide such a display device which is relatively rugged and durable, so that the numbers may be changed on the display device many times without damage to its structural integrity. 
     It is another object of the present invention to provide such a display device which may be produced, at relatively low cost, using conventional plastic molding or other suitable processes and conventional plastic resins. 
     It is still a further object of the present invention to provide such a display device which will have the appearance of a digital type electronic display and yet will be non-electronic so that it may be relatively brighter, less expensive and more durable compared to an electronic display of the same size. 
     It is a feature of the present invention to provide a display device which may be manually and easily changed to display the numerals 0 through 9. Three of the display devices may be formed, or mounted, side-by-side, to display the numbers 0 through 999. 
     SUMMARY OF THE INVENTION 
     The display device comprises a background panel; preferably having an optic or a brightly colored face. A one-piece foreground panel is attached adjacent to and parallel with the background panel. The foreground panel is provided with seven cut-out elongated portions which expose seven corresponding elongated segments of the background panel. Three of the exposed segments are parallel, horizontally aligned and evenly spaced apart and the other four exposed segments are aligned vertically in two opposite pairs to form (with the three horizontal exposed segments) the number &#34;8&#34; in block digital appearance. 
     The one-piece foreground panel is flexible and can be made of a resilient plastic resin, preferably polypropylene, and includes seven elongated flap portions. Each of the flap portions is integrally hinged to said foreground panel, preferably by a thin section of the panel, and is sized and shaped to cover a respective one of the exposed segments. 
     The display device may also include means to retain each of the flaps in a closed position (covering its respective exposed segment) and means to retain each of said flaps in an open position (exposing its respective exposed segment). 
     Preferably each of the exposed segments may be trapezoidal with inwardly directed opposite short-side ends, with the inward direction being toward the centers of the numeral &#34;8&#34;. Also, preferably, the edges of the exposed segments are parallel and closely spaced together. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other objects and features of the present invention will become more apparent from the following detailed description of the invention, taken in conjunction with the accompanying drawings, wherein: 
     FIG. 1 is a top plan view of one embodiment of the present invention; 
     FIG. 2 is a top plan view, similar to FIG. 1 but with some of the flaps in their open position to display the numeral 5; 
     FIG. 3 is an enlarged cross-sectional view taken along line A--A of FIG. 2 and looking in the direction of the arrows; 
     FIG. 4 is an enlarged cross-sectional view of an alternate flap construction; 
     FIG. 5 is a top plan view of an alternative central portion of FIG. 1 illustrating different configuration of the flaps; 
     FIG. 6 is an enlarged top plan view of a retaining means for a flap. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     With reference to FIG. 1, the digital device of this invention is shown to comprise a background panel 10 (back panel) having an optic or brightly colored face 11 adjacently attached to, and in parallel with a one-piece foreground panel 12 (front panel). The front face 11 of the back panel is of contrasting color, and may be conveniently bright or highly visible in color such as fluorescent green, optic yellow or red. 
     Panels 10 and 12 may be made of plastic resin or some other suitable material. The front panel is preferably injection molded of a plastic resin which is flexible and resilient, an example of such suitable plastic resin being polypropylene. The back panel 10 is preferably made of a commercially available sheet of a plastic resin, for example 1/16th of inch in thickness, so that it is self-supporting and relatively stiff, and may be made of polyethylene, polystyrene or some other suitable material. 
     The front panel 12 has seven elongated windows or openings 13a-13g cut-therein. The openings 13b, 13d and 13f are horizontal, spaced apart and parallel to each other. The openings 13a and 13c form one pair of vertically aligned openings and the openings 13g and 13e form a second pair of vertically aligned openings. The openings 13a-13g form the number &#34;8&#34; in block digital appearance 
     Preferably each opening 13a-13g is of generally trapezoidal configuration with the inner side, i.e., the shorter sides angled inward toward the center of the number &#34;8&#34;. 
     The front panel 12 (foreground panel) has a series of flaps integrally hinged to the panel 12. The flaps 14a-14g are preferably hinged by thin sections of panel, this type of hinge in polypropylene being generally known as the &#34;Living Hinge.&#34; It may be flexed many thousands of times without impairing its structural integrity. 
     Each of the flaps 14a-14g may cover one of the exposed openings 13a-13g. When flaps are down, the openings 13a-13g are covered and not visible. However, when the flaps are opened, the openings 13a-13g are exposed. To form the number &#34;1&#34;, the flaps 13a and 13g are opened and the remaining flaps are closed. To form the number &#34;5&#34;, as shown in FIG. 2, the flaps 14a, 14b, 14d, 14e and 14f are opened only. In a similar manner each of the numbers 0-9 may be displayed by opening the appropriate flaps in order to expose the correct segment. 
     Each of the flaps are retained in their open and closed positions by interfitting integral configurations on the flap (or the hinge) and the foreground panel. Such interfitting integral engagement may be achieved by, for example, forming, during molding, a button-shaped snap on the face of the flap and a corresponding recess or indentation in the front panel for interfitting engagement of the button-shaped snap into said recess when the flap is opened to expose a corresponding segment in the background panel. 
     In the embodiment shown in FIG. 3, the flap 15 (corresponding to one of the flaps 14a-14g) is connected to the body portion of the panel 12 by the integral hinge 16, which is a thin portion connecting flap 15 to the panel 12. 
     In the embodiment shown in FIG. 4, the flap 15a (corresponding to one of the flaps 14a-14g) fits into a cut-out segment of the front panel 11 in a cavity 19 in which the flap 15a is fitted when the segment 18 is exposed. 
     FIG. 5 shows an alternative shape of the horizontal central exposed segment 13d and its flap 14d. 
     FIG. 6 illustrates another embodiment of a means for removably holding the flap to the front panel. The front panel 12a in this embodiment has two upstanding bosses (posts) 20 and 21 in front of the flap 14h and another two bosses or posts (not shown) behind the flap 14h. A stem 22 having a knob 23 at its end is integral with the flap 14h. The bosses 20 and 21 are separated by the stem 22 and retain the knob 23 so that the flap may be lifted, by hand, when the flap position is to be changed. Other types of retaining means may alternatively be used, such as interlocking fabric with hooks (Velcro®, self-adhesive stripes (Scotch Post-It trademark of 3M company.) Each of the flaps have two retaining means, one to keep it open and one to keep it closed. The retaining means are readily released by the hand of the user to change the position of the flap. 
     The display device of this invention may be used to display from 0 to any desired number. For example, when it is desired to display numerals of 10 or higher, the foreground panel will comprise a series of cut-out portions and flaps arranged in rows to form 2 or more figure &#34;8&#34;. In this manner, the first row may be used to form one digit, say 7, and the second row may be used to form another digit, say 6, to display the numeral &#34;76&#34;. As may rows may be used as is necessary to display any desired number such as &#34;895&#34;, &#34;1101&#34; and so on. 
     While the invention has been described and illustrated with a certain degree of particularity in order to facilitate its understanding, it must be understood that numerous changes and modifications will be suggested by the present description. Such changes and modifications are obvious from the foregoing description and are therefore within the scope of this invention.