Abstract:
A simulated stone or brick column which is fabricated by a method which involves providing a hollow closed mold which has an inner face in the form of a reverse image of the desired stone or brick surface. Two casting materials are sequentially introduced into the mold and in each case the mold is rotated about two perpendicular axes so that the casting material coats the inner face of the mold and results in the formation of a hollow column having the external appearance of the desired stone or brick surface. The two casting materials form an outer layer which has a texture and contour which simulate a stone or brick surface, and an inner layer which is adheredt to the outer layer and imparts high strength with minimal weight. A standard mailbox and newspaper tube can be integrally molded within the column.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention relates to a simulated stone or brick column which is configured to serve as a support for a plaque, light, or mailbox, or as a fence post. 
         [0002]    Columns and posts of the described type are conventionally formed of wood, stone, or brick. Wooden posts quickly deteriorate and become unsightly, while stone or brick posts are expensive to fabricate at their location of use. Also, when such columns or posts are mounted adjacent a roadway, they can cause significant damage if accidentally impacted by an automobile. 
         [0003]    It is accordingly an object of the present invention to provide a column or post of the described type, which presents an attractive appearance, which is long lasting, and which is relatively inexpensive to fabricate and maintain. 
         [0004]    It is also an object of the present invention to provide a simulated stone or brick column which can be placed adjacent a roadway to support a mailbox and/or newspaper tube, and which is of low weight, and is designed to easily break away from its mounting, to thereby minimize the risk of damage to an automobile which accidentally impacts the column. 
         [0005]    It is another object of the present invention to provide a column or post which can be mass produced at a manufacturing facility and then easily mounted as a one-piece unit at its point of use. 
         [0006]    It is still another object to provide a column or post of the described type which is highly resistant to deterioration, and yet is of low weight so as to further facilitate its mounting at the intended point of use. 
       SUMMARY OF THE INVENTION 
       [0007]    The above and other objects and advantages of the invention are achieved by the provision of a simulated stone or brick column which is fabricated by a method which involves providing a hollow closed mold which has a peripheral side wall and opposite end plates, and with at least the peripheral side wall having an inner face which comprises a reverse image of a stone or brick surface. A first liquid casting material is introduced into the mold, and the mold is rotated about two different axes so as to cause the material to coat the inner face of the side wall and the opposite end plates. The first casting material is allowed to cure and harden, and a second liquid casting material is then introduced into the mold and the rotation is repeated. After the second casting material hardens, the mold is opened to permit removal of the molded column. The peripheral side wall of the resulting molded column will thus have an exterior surface in the form of a positive image of the stone or brick surface. 
         [0008]    The first liquid casting material thus forms an outer layer of the wall of the resulting molded column, and it is formulated to provide, upon hardening, the realistic look and texture of stone or brick. The second liquid casting material is formulated to provide, upon hardening, an inner wall layer which provides significant tensile strength while adding minimal weight to the resulting column. 
         [0009]    The method of the present invention readily lends itself to an embodiment wherein a standard mailbox may be integrally mounted in the column. In such case, the hollow interior of the molded column can be partially or completely filled with an expandable foam forming material so that the resulting foam securely supports the portion of the mailbox which extends into the interior of the column. 
         [0010]    In other embodiments, the resulting molded column can be used as a fence post, with a railing mounted between adjacent posts, or the column can be used to support a plaque with a house number, a light, or the like. 
         [0011]    In all of the above embodiments, the column can be easily mounted upon a flat foundation footer at its final point of use, by utilizing an adhesive which is positioned between the bottom wall of the column and the footer. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    Some of the objects and advantages of the present invention having been stated, others will appear as the description proceeds, when considered together with the accompanying drawings, in which: 
           [0013]      FIG. 1  is a perspective view of a simulated stone mailbox supporting column which embodies the present invention; 
           [0014]      FIG. 2  is an exploded perspective view of a step in the fabrication of the mold used to practice the present invention; 
           [0015]      FIGS. 3A ,  3 B, and  3 C are fragmentary cross sectional views taken along the line  3 - 3  of  FIG. 2  and illustrating additional steps in the fabrication of the mold; 
           [0016]      FIG. 4  is a perspective view of a portion of the interior of the mold of the present invention; 
           [0017]      FIG. 5  is a fragmentary sectional view taken along the line  5 - 5  of  FIG. 4 ; 
           [0018]      FIG. 6  is an exploded perspective view of the mold in an inverted orientation; 
           [0019]      FIG. 7  is a perspective view of the mold during the step of introducing a first liquid casting material into the mold while it is inverted; 
           [0020]      FIG. 8  is a perspective view of the step of rotating the mold about two axes; 
           [0021]      FIG. 9  is a fragmentary sectional view taken along the line  9 - 9  of  FIG. 8 ; 
           [0022]      FIG. 10  is a fragmentary perspective view during the step of introducing a second liquid casting material into the mold; 
           [0023]      FIG. 11  is a view similar to  FIG. 8  and showing the second rotation step; 
           [0024]      FIG. 12  is a cross sectional view of the mold during the step of introducing a foam forming material into the mold; 
           [0025]      FIG. 13  is an exploded perspective view showing the step of disassembling the mold from the molded column; 
           [0026]      FIG. 14  is a cross sectional view of the molded column after the foam forming material has been introduced; 
           [0027]      FIG. 14A  is a fragmentary enlarged view of the wall of the resulting molded column; 
           [0028]      FIG. 15A  is a fragmentary perspective view showing the step of applying a rubber-like stencil upon the top portion of the column so as to cover the grout lines of the column; 
           [0029]      FIG. 15B  is a fragmentary perspective view showing one of the spray painting steps; 
           [0030]      FIG. 16A  is a fragmentary perspective view showing the step of applying a rubber-like stencil upon two side walls of the column; 
           [0031]      FIG. 16B  is a perspective view of the spray painting of the side walls of the column; 
           [0032]      FIG. 17  is a fragmentary perspective view showing the step of re-assembling the cover and flag of the mailbox; 
           [0033]      FIG. 18  is a perspective view illustrating the application of an adhesive to the bottom wall of the column during its mounting upon a foundation footer; 
           [0034]      FIG. 19  is a perspective view of the finished column which schematically illustrates its internal construction; 
           [0035]      FIG. 20  is a perspective of a second embodiment of the invention in which the molded column serves as a fence post; 
           [0036]      FIG. 20A  is an exploded view showing the mounting of a railing to one of the fence posts of  FIG. 20 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0037]    Referring more particularly to the drawings,  FIG. 1  illustrates a finished mailbox supporting column which embodies the present invention. The column  10  is of elongate tubular configuration composed of a peripheral side wall  11 , an upper end wall  14 , and a bottom end wall  15  which are joined together to form a hollow enclosure, note  FIG. 14 . The peripheral side wall  11  is composed of four peripheral side wall members  12  which form a square when viewed in horizontal cross section, but round or other cross sectional configurations are possible in the practice of the present invention. 
         [0038]    The four side wall members  12 , the upper end wall  14 , and the bottom end wall  15  each comprise an outer layer  16  (note  FIG. 14A ) of a material which is formulated to provide a realistic look of stone or brick and grout in the finished column. Each of these walls also comprises an inner layer  18  which comprises a mixture of a polymeric resin and fiber strands which is formulated to provide tensile strength while adding minimal weight to the resulting molded column. Also, the outer layer  16  has an outer surface which is shaped to resemble a stone or brick wall with grout between the stones or bricks. 
         [0039]    In one preferred embodiment, the column  10  mounts a standard mailbox  20  which extends through one of the side wall members  12  so that the openable end of the mailbox is accessible from the outside of the column and the rear end portion is within the hollow enclosure formed by the walls of the column. Also, as seen in  FIG. 14 , the hollow enclosure is partially filled with a foam material  21  so as to surround and support the rear end portion of the mailbox within the enclosure. 
         [0040]    The above described support column  10  is preferably fabricated by a molding process which is described in detail in the following paragraphs. 
       The Fabrication of the Mold 
       [0041]    As a first step in the production process, a mold  24  is fabricated in which the column  10  is molded. 
         [0042]    As is illustrated in FIGS.  2  and  3 A- 3 C, the fabrication of the mold  24  begins with the fabrication of a model which embodies the configuration and contoured surface of the desired column. The model may be formed by hand from stones or bricks, or by any other conventional technique. 
         [0043]    Once the model is fabricated, it is covered with a layer of clay on all four sides and the top in the illustrated embodiment. The clay has a composition and consistency similar to that of conventional modeling clay used to make pottery, and it adheres to the model. The thickness of the clay is made as uniform as possible, and is typically about ¾ inches thick. The clay does not cover the bottom of the model in the illustrated embodiment. 
         [0044]    Next, four outer panels  26  are formed, by for example spraying a coating of a fiberglass containing resin, such as polyester, onto the clay covered model. The outer panels  26  are preferably formed one at a time, and suitable forms are positioned along the edges and top and bottom to form side and end flanges on each panel. These flanges serve to interconnect the panels in a manner which will become apparent as the description proceeds. The fiberglass/resin coating is allowed to harden, resulting in the formation of a rigid outer panel  26  having a flat central portion which is surrounded by raised flanges. 
         [0045]    A top end plate  28  is fabricated by the same technique, and a previously formed bottom end plate  29  is positioned to underlie the model and be attached to the flanges of the outer panels, note  FIG. 13 . 
         [0046]    The flanges of the outer panels  26  and the top and bottom end plates  28 ,  29  are then drilled, to accommodate bolts for securing the components together, as described below. 
         [0047]    The outer panels  26  are then removed one at a time, and the underlying clay is stripped from the model. The removed outer panel is then repositioned with the other outer panels and attached thereto by the bolts which join the adjacent flanges. This forms a void in the area previously occupied by the clay beneath the outer panel which has been removed and replaced, as seen in  FIG. 3B . The void is then filled with a rubber-like liner material which is introduced through one or more holes (not shown) which are adjacent the upper flange of each panel. Also, one or more small vent holes (not shown) may be formed adjacent the bottom of each panel. During this filling operation, the assembly is preferably placed in a horizontal position, with the removed and replaced panel facing upwardly, and the liner material flows into all areas of the void between the model and the panel  26 . Note in this regard that for the first filling operation, the remaining clay forms the boundary along both sides and top of the void. 
         [0048]    Upon hardening, a liner  30  is formed and the inner surface of the liner will thereby be formed as a reverse image of the surface of the model. 
         [0049]    The second through fourth outer panels  26  are sequentially removed, with the clay under each panel being stripped, and with the resulting void being filled with the liner material in the above described manner. The top end plate  28  is then removed, and the underlying clay is stripped to form a void which is filled with the liner material, note  FIG. 3C . 
         [0050]    As seen in  FIG. 9 , a number of bolts  32  may be mounted in the outer panels  26  to secure the liner to the panels. Each outer panel  26  and its attached liner  30  is referred to herein as a side wall member  34  of the mold and the four side wall members collectively form a peripheral side wall of the mold. 
         [0051]    As final steps in fabricating the mold  24 , the side wall members  34  and top end plate  28  are separated from each other and removed from the model. Since the liner  30  is fabricated sequentially beneath each outer panel  26  and the top end plate  28 , there will be break lines formed between the several sections of the liner, and cutting of the liner is not usually required during this separation operation. The side wall members  34  and top and bottom end plates  28 ,  29  are then re-assembled by interconnecting the adjacent flanges to form a hollow closed mold, with the inner face of the side wall members  34  of the mold, and the inner face of the top end plate  28 , forming a reverse image of the model and thus the surface of the desired final column. 
       The Mounting of the Mailbox in the Mold 
       [0052]    As best seen in  FIGS. 4-6 , a standard mailbox  20  is mounted to extend into the interior of the mold  24 . To facilitate the handling of the side wall members  34 , two of the side wall members may be joined to form an L-shaped configuration as seen in  FIG. 4 . This permits the two joined side wall members to stand upright. Also, the conventional flag and hinged front door of the mailbox  20  are initially removed. 
         [0053]    Next, an aperture  36  is cut or otherwise formed which extends through the liner  30  and outer panel  26  of one of the side wall members  34 , note  FIG. 5 , with the aperture  36  having an outline which closely matches the peripheral cross-sectional outline of the mailbox  20 . A closure panel or “door”  38  is then attached to the exterior of the outer panel so as to close the aperture, and the mailbox is inserted into the aperture so that its open front end abuts the door  38 . A dowel rod  39  is joined to the rear end of the mailbox and extends through and is secured to the outside of the door so as to firmly hold the mailbox in the aperture in the position shown in  FIGS. 4 and 5 . 
         [0054]    While the present embodiment shows a mailbox joined to the interior of the mold, it will be appreciated that a newspaper tube or other similar tubular member can be joined in this fashion. 
       The Molding Process 
       [0055]    The side wall members  34  and the top and bottom end plates  28 ,  29  are joined to form a closed mold  24 , and the mold is then inverted as shown in  FIGS. 6 and 7 . A first liquid casting material  40  is then poured into the hollow mold through an aperture  41  in the bottom end plate  29  using a funnel  42 . The aperture is then closed with a urethane rubber mold plug  44 , which is fitted with a vent (not shown) that prevents the heat generated by the exothermic reaction from pressurizing the interior of the mold during curing. The mold is then mounted on a frame  45  which is configured to simultaneously rotate the mold  24  about two axes which are perpendicular to each other. The minor axis A is set to about six rotations per minute and the major axis B is set to about four rotations per minute. 
         [0056]    Such rotation causes the liquid casting material  40 , which initially forms a puddle in the bottom of the mold, to flow onto and cover all interior surfaces of the liner  30  on all four side wall members  34  as well as the liner on the top end plate  28  and the bottom plate  29 , note  FIG. 9 . Centrifugal force is not required to effect the coating operation, and thus the low rotational speeds as indicated above are sufficient. The dual rotation typically continues for about 20-22 minutes, and the casting material is then allowed to cool and harden. Upon hardening, the first liquid casting material  40  forms the outer layer  16  ( FIG. 14A ) of the side wall member  12  of the molded column  10  and as described above. The average thickness of the hardened outer layer  16  is preferably between about 3/32 to 3/16 inches. 
         [0057]    A preferred first liquid casting material  40  has the following composition, which is thoroughly mixed before use: 
         [0058]    First Liquid Coating Material Mix Composition 
         [0000]    
       
         
               
               
               
             
           
               
                   
                   
               
             
             
               
                   
                  30 lbs. 
                 Gypsum (Densite HL - GP Gypsum Corp.) 
               
               
                   
                  20 lbs. 
                 Sand 
               
               
                   
                  15 lbs. 
                 Liquid Resin (Forton VF 812 - 
               
               
                   
                   
                 EPS/CCA) 
               
               
                   
                  3 lbs. 
                 Dry Resin (Melamine Formaldehyde 
               
               
                   
                   
                 Resin Powder - BTLSR Toledo, Inc.) 
               
               
                   
                  68 grams 
                 Ammonium Chloride Hardener (The 
               
               
                   
                   
                 Dallas Group of America, Inc.) 
               
               
                   
                  4 fluid Ounces 
                 Accelerator (H 2 O + Aluminum Sulfate) 
               
               
                   
                 504 grams 
                 Pigment - Raw Umber (Kremmer 
               
               
                   
                   
                 Pigments) 
               
               
                   
                 160 grams 
                 Pigment - Black (Kremmer Pigments) 
               
               
                   
                   
               
             
          
         
       
     
         [0059]    After the first liquid casting material has set up and hardened in the mold  24 , a second liquid casting material  48  is mixed and introduced into the mold via the same aperture  41  in the bottom end plate  29 , note  FIG. 10 . The aperture is closed with the plug  44  and the mold is then rotated about the same two axes ( FIG. 11 ) so as to cause the second liquid casting material to move outwardly and coat the hardened first material, i.e. the outer layer  16 . This dual rotation typically continues for about 13 minutes, and the second material is then allowed to harden. Upon hardening, the second liquid casting material  48  forms the inner layer  18  ( FIG. 14A ) of the side wall member of the molded column  10 , which self adheres to the outer layer  16 , and which has an average thickness of between about 3/32 and 3/16 inches. 
         [0060]    A preferred second liquid casting material  48  has the following composition: 
         [0061]    Second Liquid Coating Material Mix Composition 
         [0000]    
       
         
               
               
               
             
           
               
                   
                   
               
             
             
               
                   
                  5 quarts 
                 8033 A Polyurethane (T. A. Davies Co.) 
               
               
                   
                  5 quarts 
                 8033 B Polyurethane (T. A. Davies Co.) 
               
               
                   
                 10 grams 
                 Chopped Fiberglass strands 
               
               
                   
                   
               
             
          
         
       
     
         [0062]    In a preferred embodiment, the mold  24  is next moved to an inverted position and held in this position while a foam forming composition  50  is delivered into the mold through the aperture  41  in the bottom end plate  29 . The resulting foam  21  typically surrounds and supports the mailbox  20 , and occupies about ⅔ of the height of the inverted mold as represented by the letter A in  FIG. 12 . The remaining portion of the height which is represented by the letter B, remains open. 
         [0063]    A preferred foam forming composition comprises: 
         [0000]    
       
         
               
               
             
           
               
                   
                   
               
             
             
               
                   
                 ½ gal. polymeric isocyanate - A 
               
               
                   
                 ½ gal. Polyurethane Foam Resin - B 
               
               
                   
                 (Instapak FLOWRITE - Sealed Air) 
               
               
                   
                   
               
             
          
         
       
     
         [0064]    Finally, after the foam composition  50  has cured to form the foam  21 , the mold  24  is moved to its upright orientation and the side wall members  34  and top and bottom end plates  28 ,  29  are separated, note  FIG. 13 . At this point, it should be noted that the liners  30  adhere to the rigid outer panels  26 , and the same components can be used to form additional molded columns without forming new liners. However, the liners can be stripped from the outer panels and new liners can be formed by the process described above, if the liners become damaged or otherwise need to replaced after one or more columns have been molded. 
         [0065]    The molded column  10  has the appearance as shown in  FIG. 14  at this point. The corner edges of the product may contain flashings formed by excess material where the mold panels are joined together, and if necessary such flashings can be removed by use of a hand chisel. 
       The Finishing of the Molded Product 
       [0066]    To highlight the appearance of stones in the illustrated embodiment, the top portion of the molded column  10  is spray painted with one or more colors. First, the top portion is covered with a rubber-like stencil  52  which is configured to match the outline of the grout lines between the stones, note  FIG. 15A . The remaining portion of the column is wrapped with a protective sheeting  53 , and a base coat is applied to the top portion of the column by spraying. When it has dried, one or more highlight colors may be applied by spraying. Typically, the base coat is sprayed over the entire top portion, and the next colors are sporadically applied to highlight particular “stones”. The stencil  52  and protective sheeting  53  are then removed. 
         [0067]    The molded column  10  is then laid horizontally upon a suitable dolly (not shown), and a rubber-like stencil  54  is applied to cover the grout lines on two sides of the column. The top portion of the column and mailbox opening are covered with a protective wrap  55 . These two sides are then spray painted as described above, and the product is rotated through  1800  to expose the other two sides, which are then similarly covered with a stencil  54  and spray painted, note  FIGS. 16A and 16B . 
         [0068]    The stencils  52 ,  54  for the top portion of the column and the sides of the column may be initially fabricated by extruding a line of urethane rubber composition along the grout lines using a caulking gun. Upon hardening, a rubber-like network is produced which conforms closely to the grout lines. Once formed, the stencils can be re-used with a number of molded columns which are produced in the same mold. 
         [0069]    The last step in the finishing process is to spray the entire column  10  with a sealer. This prevents moisture intrusion and lengthens the life of the paint. The protective wrap  55  is preferably retained on the mailbox during the spraying operation. 
         [0070]    As shown in  FIG. 17 , the front door and the flag of the mailbox  20  are then re-attached to the box and the column respectively. 
       Assembly at Final Location 
       [0071]    The finished column  10  and integral mailbox  20  are adapted to be easily mounted upon a cement foundation footer  56  as seen in  FIGS. 18 and 19 . The lower surface of the bottom end wall  15  of the column is preferably smooth and flat, resulting from the smooth and flat interior surface of the bottom end plate  29  of the mold, note  FIG. 13 . As a result, a suitable adhesive  58  can be applied to the bottom end surface, and/or the footer, so as to securely support the column  10  when it is mounted upon the footer and the adhesive dries. One or more upright bolts  59  can be mounted to extend upwardly through the footer and also through apertures (not shown) formed in the bottom end wall of the column, to further support the column if desired. 
         [0072]      FIG. 19  is a schematic representation which indicates that the upper ⅔ of the column  10  is filled with the foam  21  and is thus relatively solid, while the lower ⅓ is hollow. The hollow and relatively weak bottom third permits the column to easily break apart or break away from the foundation footer  56  upon accidental impact, such as by an automobile. The damage to an automobile which impacts the column would thereby be minimized. 
         [0073]    The embodiment of  FIG. 19  also includes a hollow newspaper tube  60  which can be mounted in the column as described above with respect to the mailbox. 
       The Fencepost Embodiment 
       [0074]    The features and advantages of the present invention can be achieved with a number of products in addition to a mailbox supporting column as described above. For example, and as illustrated in  FIGS. 20 and 20A , the invention can be employed to fabricate a simulated brick fencepost  62 . In this embodiment, a railing  64  can be easily joined between adjacent fenceposts, utilizing a plurality of mounting pads  65  which are shaped to match the contour of the “stones”, or in this case the “bricks”, and mounting brackets  66 . In this embodiment, the presence of interior foam is most likely unnecessary, and the entire interior of the fencepost  62  could be hollow. 
         [0075]    Many modifications and other embodiments of the invention set forth herein will come to mind to one skilled in the art to which the invention pertains having the benefit of the teachings presented in the foregoing description and the associated drawings. While the invention has been described herein as being useful as a support for a plaque, light, or mailbox, or as a fence post, other uses are possible. For example, the column could be formed to surround and thus provide an ornamental outer cover for a structural beam or piling. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.