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.
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.
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.
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.
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.
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.
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.
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.
In another embodiment, a single liquid casting material is used to rotary-cast the column as a single layer. The casting material can comprise a blend of a polymer resin component, a catalyst component that, when blended with the polymer resin component, initiates an exothermic chemical reaction that ultimately results in the casting material curing and hardening, and a filler component distributed throughout the casting material. The polymer resin component can be one or more of polyester resin or vinyl ester resin, and can include one or more other additives. The catalyst component can comprise methyl ethyl ketone peroxide (MEKP) or the like. The filler component can comprise one or more of inorganic particulate fillers (e.g., calcium carbonate, aluminum trihydrate, or the like), organic particulate fillers (e.g., pulverized pecan shells, wood flour, or the like), or lightweight microballoons or microspheres (e.g., glass microballoons, phenolic resin microballoons, or the like).
The method of the present invention readily lends itself to an embodiment wherein a mailbox may be integrally mounted in the column.
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.
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 between the bottom wall of the column and the footer.
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:
Referring more particularly to the drawings,
The four side wall members 12, the upper end wall 14, and the bottom end wall 15 each comprise an outer layer 16 (note
In one preferred embodiment, the column 10 mounts a 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
The above described support column 10 is preferably fabricated by a molding process which is described in detail in the following paragraphs.
As a first step in the production process, a mold 24 is fabricated in which the column 10 is molded.
As is illustrated in FIGS. 2 and 3A-3C, 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.
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.
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.
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
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.
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
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.
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
As seen in
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.
As best seen in
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
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 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
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
A preferred first liquid casting material 40 has the following composition, which is thoroughly mixed before use:
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
A preferred second liquid casting material 48 has the following composition:
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
A preferred foam forming composition comprises:
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
The molded column 10 has the appearance as shown in
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
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 180° to expose the other two sides, which are then similarly covered with a stencil 54 and spray painted, note
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.
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.
As shown in
The finished column 10 and integral mailbox 20 are adapted to be easily mounted upon a cement foundation footer 56 as seen in
The embodiment of
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
The above-described embodiments of a simulated stone or brick column or fencepost have a two-layer structure in which a first layer is rotationally cast in the mold using a first liquid casting composition, after which a second layer is rotationally cast using a second liquid casting composition that is different from the first liquid casting composition. In particular, in order to achieve adequate strength properties of the column while also achieving the realistic appearance of a stone or brick column (including all of the very fine detail that a real stone or brick column would have, as reflected in the mold made from a real stone/brick column), it was necessary to employ one type of casting composition suitable for achieving the desired fine detail, which formed the first or outer layer of the column, and then to employ another different type of casting composition having substantial strength properties, which formed the second or inner layer of the column. Specifically, as described in a preferred embodiment above, the second casting composition found to be particularly suitable comprised a polyurethane composition containing chopped fiberglass strands.
The alternative embodiment described now differs from the previous embodiment in that the column is made as a single layer of a single type of liquid casting material. The casting material employed in this embodiment is able simultaneously to achieve the desired fine detail in the outer surface of the column and to provide the requisite strength properties, which previously had been thought to be achievable only by including the fiber-reinforced polyurethane layer.
The liquid casting material in accordance with this embodiment is composed of a blend of a polymer resin component, a catalyst component that, when blended with the polymer resin component, initiates an exothermic chemical reaction that ultimately results in the casting material curing and hardening, and a filler component distributed throughout the casting material. The polymer resin component can be one or more ester resins such as polyester resin or vinyl ester resin or the like. To achieve the desired degree of rigidity of the column without excessive brittleness, the resin component can be a blend of a rigid ester resin and a flexible ester resin. The catalyst component can comprise methyl ethyl ketone peroxide (MEKP) or the like.
The filler component can comprise one or more of inorganic particulate fillers (e.g., calcium carbonate, aluminum trihydrate, or the like), organic particulate fillers (e.g., pulverized pecan shells, wood flour, or the like), or lightweight microballoons or microspheres (e.g., glass microballoons, phenolic resin microballoons, or the like). The inclusion of microballoons largely contributes to the surprisingly lightweight nature of the finished column, while still achieving the needed strength.
The casting material can also include additives such as a defoaming or air-releasing agent to substantially prevent the formation of air bubbles in the exterior surface of the casting, a thinning agent or solvent to achieve the desired degree of fluidity of the material, a pigment (e.g., titanium dioxide or the like), etc.
In one embodiment, the casting material comprises, by weight, approximately 60-65% polyester resin, approximately 30-35% filler, and approximately 1% MEKP catalyst, with the balance being made up of additives as noted above. Notably, the casting material is free of any fibrous reinforcing material such as fiberglass or the like.
The alternative embodiment also differs from the previous embodiment in the way in which a mailbox-accommodating receptacle and a newspaper tube-accommodating receptacle are formed in the column. In particular, a mailbox mold plug 100 (
The first step in fabricating the mailbox mold plug 100 is to build a rigid core that closely resembles the overall size and shape of the desired finished plug while allowing for an approximately ½ inch-thick outer coating to be applied later in the process. The rigid core is then equipped with two heavy-duty threaded inserts that are positioned in the mating face of the plug (
It should be understood that the mailbox mold plug 100 need not have a length equal to the length of the mailbox, and in fact it is preferred for the mailbox mold plug to have a substantially shorter length as shown in the drawings.
It is also to be understood that a newspaper tube mold plug 110 (
With reference to
Next, the mailbox mold plug 100 is attached to the appropriate side wall 126 via two hex head bolts threaded into the threaded inserts in the plug. When a newspaper tube is also to be included, a newspaper tube mold plug 110 is attached to the side wall in the same manner.
The remaining side wall members 126 are joined (
Such rotation causes the liquid casting material, which initially forms a puddle in the lowest points of the mold, to flow onto and cover all interior surfaces of the liner on all four side wall members 126 as well as the liner on the top and bottom wall members. The liquid casting material also coats the exterior surfaces of the mailbox mold plug 100 and newspaper tube mold plug 110 and forms respective openings and sleeves in the molded column having perimeters corresponding to the exterior shapes of the mailbox and newspaper tube, respectively. 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 20-25 minutes, allowing the casting material to harden. The average thickness of the hardened layer is ⅜ inches.
The mold is then removed from the rotational frame and disassembled, revealing the completed casting (
The coating of the mailbox mold plug 100 by the casting material results in the molded column having a mailbox-shaped opening 102 and sleeve 104 extending through the peripheral side wall into the hollow interior of the molded column. Since the mailbox mold plug has a length substantially shorter than the mailbox, the sleeve 104 likewise has a length substantially shorter than the mailbox length. Once the bottom wall 106 of this sleeve is removed by a suitable cutting tool, the result is an opening 102 and sleeve 104 extending through the peripheral side wall of the column for receiving a mailbox.
Similarly, the coating of the newspaper tube mold 110 plug by the casting material results in the molded column having a newspaper tube-shaped opening 112 and sleeve 114 extending through the peripheral side wall into the hollow interior of the molded column.
Along the corner edges of the column where the mold panels are joined together, flashings may be formed by excess material and therefore must be removed by use of a hand chisel or suitable rotary tool prior to finishing.
Finally, a residual film that forms on the casting as a result of the exothermic chemical reaction must be removed by use of a hot water pressure-washing system or other suitable means prior to finishing.
Prior to finishing, a suitable mailbox container must be mounted in the mailbox-shaped opening that was cast into the column earlier in the fabrication process. The mailbox container 80 is slid into the opening 102 (
Once the mailbox container 80 is secured to the column, a clearance gap between the mailbox container and the opening 102 in the side of the column must be filled by way of a conventional grouting technique, which involves squeezing a cement-based material through a cone-shaped bag, filling the void between the molded column and the mailbox (
A standard newspaper tube (not shown) is installed in the opening 112 and sleeve 114 formed by the newspaper tube mold plug 110, in the same general manner as described above with respect to the mailbox container, so that an open end of the newspaper tube is accessible through the opening 112 in the peripheral side wall.
To create the authentic appearance of stone or brick, the column is spray painted with one or more colors.
Throughout the entire finishing process, the column can be stood in the natural upright position and placed on a hydraulic scissor lift table equipped with a 360 degree rotating platen, allowing for the column to be oriented and manipulated with minimal physical effort.
First, a tinted primer/bonding coat is applied over the entire column, which sets the general undertone of the finish. Once the primer coat has dried, in order to establish a firm base, a second coat of conventional paint tinted the same color as the primer coat is applied over the entire column. When the second coat has dried, the entire column is systematically sprayed with a contrasting color of conventional paint and then quickly rubbed with a damp cloth before the paint is allowed to dry, allowing the underlying contrasting color to bleed through, which creates authentic-looking veining and simulates weather-imposed details. After drying, one or more highlight colors of conventional paint are applied sporadically around the entire column to highlight particular “stones”.
The last step in the finishing process is to spray the entire column with a sealer preventing both moisture intrusion and weather-related damage as well as UV degradation.
The simulated stone column is installed at a field site in substantially the same manner as described above in connection with the first embodiment.
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.
The present application is a continuation-in-part of U.S. patent application Ser. No. 11/435,119 filed on May 16, 2006, currently pending, the entire disclosure of which is hereby incorporated herein by reference.
Number | Date | Country | |
---|---|---|---|
Parent | 11435119 | May 2006 | US |
Child | 12858188 | US |