This application claims priority on Provisional U.S. Patent Application Ser. No. 61/128,531, filed May 22, 2008, the disclosures of which are incorporated by reference.
The present invention relates to products made from artificial stone, and particularly to a modular firepit and outdoor grill constructed of artificial stone slab members, and more particularly, one which has a uniform construction method utilizing a single block to be easily assembled, disassembled, re-assembled, and inexpensively manufactured.
Stone firepits and barbeque grills are frequently found in outdoor locations where their durability and aesthetics permit containment of a fire for recreational purposes, such as for campers at campsites and parks, as well as public and private outdoor entertainment areas. Most of such firepits or grills are made from real stone and many are consolidated into a structural object by adhering the stone elements with the use of cement or concrete binder. Both the weight of such assembled firepits and grills and the complexity of the necessary assembly process do not lend them to be relocated either through disassembly or by transporting while fully assembled.
The ability to have a product which appears to be made of stone and has a configuration visually similar to a real stone fire/barbeque pit, but which can be easily assembled and disassembled has value for end users wishing the benefits of a stone fire/barbeque pit without having the limitations of non transportability.
Such an advantageous product has thus far been unavailable. One invention attempting to fulfill those needs is shown by U.S. Pat. No. 5,186,161 to Shumock. The Shumock invention is for a modular fireplace, and as described, it utilizes fire blocks with interlocking joints. While the modular nature of the Shumock invention permits transportability, the ease of relocation is severely hampered by the complexity of the various different joints utilized for the blocks, and by the multitude of various shaped and sized blocks required to construct the Shumock fireplace. In addition, there is no versatility in the end-product, in that only one unique fireplace configuration is attainable, and furthermore, it has limited adaptability to alternatively serve as an outdoor grill.
In order for such a modular fireplace to realistically be transportable, a simpler means of assembly needed to be created. The problems of the prior art are solved herein with novel design which permits assembly of a firepit or grill with only a single configuration of block.
A fire barbeque pit is assembled from a series of artificial stone slabs formed from concrete which has been surface pigmented with particles of a metal oxide to mimic the appearance of stone. The slabs have interlocking male and female grooves which allow for perpendicular inter-locking placement of the slabs. The indentations allow for the slabs to overlap at their extremities creating a stable structure which can be assembled and disassembled without the use of cement or binding concrete to consolidate the structure. This allows for easy on-site assembly, subsequent disassembly and transportation from the site after use.
In one preferred embodiment of the invention the slabs of the present invention have a body portion with top surface, bottom surface and a pair of side surfaces that extend from the top surface to the bottom surface. The slab formed by these surfaces has a generally rectangular or square cross section. The slab also has a first end portion and a second end opposite the first end. Each of the end portions is separated from the body portion by at least one recessed portion. The recessed portion is designed to mate with a recessed portion of a second slab that is positioned transverse to the first slab thereby to removably interlock to the slabs. In forming the barbecue of the present invention, there is a base slab where there are recesses on the top surface and there is a bottom surface that preferably extends from said first end to said second end without a recess portion. This will provide a flat surface for the barbecue to rest. Similarly, the top slab has a recess on the bottom surface with the top surface relatively flat or finished. The lengths of the slabs can vary depending on how large a barbecue grill is desired.
It is an object of this invention to provide a modular fire pit which may be assembled and disassembled for relocation.
It is a further object of this invention to provide a modular barbeque grill which may be assembled and disassembled for relocation.
It is another object of this invention to provide an interlocking block design which permits construction utilizing a minimum number of different shaped and sized blocks to reduce complexity of the assembly process, disassembly, and re-assembly.
It is another object of this invention to provide a block which is constructed of a lightweight material.
It is another object of this invention to provide an aesthetically appealing block which may be adapted to resemble stone, brick, or decorative mosaic tile.
It is another object of this invention to provide a block construction from lightweight concrete.
It is another object of this invention to provide a block with a joint design that may be utilized on every block of the assembly.
It is another object of this invention to provide a design which permits easy adjustment of the height of the fire area.
It is another object of this invention to provide a design which permits easy adjustment of the height of the grilling area.
It is another object of this invention to provide a design which permits easy adjustment of the height of a block fume hood.
FIG. 1 is a perspective view of a barbecue grill with a telescoping block fume hood, identifying the various blocks required for its construction.
FIG. 2 is a perspective view of a barbecue grill with a back splash block, identifying the various blocks required for its construction.
FIG. 2A is a cutaway view of one wall of an embodiment of the current invention, displaying grill support dowel pins.
FIG. 3 is a perspective view of a fire pit of the current invention, identifying the various blocks required for its construction.
FIG. 4 is a perspective view of a fire pit according to the current invention, which has an alternative top course of upper blocks without exposed top notches.
FIG. 5 is a top view of a top grill grate of the current invention.
FIG. 6 is a top view of a bottom grill grate of the current invention.
FIG. 7 is a perspective view of the second embodiment of the current invention where it is fitted with a removable unitary fume hood.
FIG. 7A is a front view of the removable unitary fume hood.
FIG. 7B is a side view of the removable unitary fume hood.
FIG. 7C is a top view of the removable unitary fume hood.
FIG. 8A is a series of three views describing a plain slab member (block A) of the current invention.
FIG. 8B is a series of three views describing a slab member (block B) of the current invention.
FIG. 8C is a series of three views describing a spacer slab (block C) of the current invention.
FIG. 8D is a series of three views describing a transition slab member (block D) of the current invention.
FIG. 8E is a series of three views describing a splash slab member (block E) of the current invention.
FIG. 8F is a series of three views describing block F of the current invention.
FIG. 8G is a series of three views describing a short slab member (block G) of the current invention.
FIG. 8H is a series of three views describing a variable length slab member (block H) of the current invention.
FIG. 8I is a series of three views describing a shorter variable length slab member (block I) of the current invention.
FIG. 8J is a series of three views describing a shortest variable length slab member (block J) of the current invention.
FIG. 8K is a series of three views describing short plain slab member (block K) of the current invention.
FIG. 9A is a perspective view representing an alternative notch configuration of the current invention, which uses a cylindrical protrusion and indentation.
FIG. 9B is a perspective view representing an alternative notch configuration of the current invention, which uses a V-shaped protrusion and indentation.
FIG. 9C is a perspective view representing a third alternative notch configuration of the current invention.
FIG. 9D is a perspective view representing a fourth alternative notch configuration of the current invention.
The design of the basic member of this invention provides for an easily assembled and disassembled fire pit or barbeque grill. The design also readily lends itself to adding additional features which may be marketed separately or as a more complete package.
A fully featured barbeque grill 10 is shown in the photograph of FIG. 1, and a basic fire pit 13 is shown in FIG. 3. Construction of the fully featured barbeque grill 10 shown in FIG. 1 can be achieved by adding blocks to the fire pit of FIG. 3, which dictates that an initial discussion of one possible embodiment of this invention should be the fire pit 13.
There are many possible fire pit shapes that can be formed from the blocks of the current invention, such as, but not limited to, a fire pit whose footprint forms a V-shape, a C-shape, a U-shape, a rectangle, or other polygon shape, or even a curved shape. To be illustrative of such possibilities, a rectangular fire pit 13 is described.
The fire pit 13 shown in FIG. 3 may be constructed using multiple copies of the same formed block shape. The fire pit 13 is created by assembling the blocks to create a series of tiers, or using brick laying terminology, a series of courses. The number of course utilized may be determined according to the needs of the user. To have a shallow height fire pit 13 which may be more easily enjoyed or viewed while sitting on the ground or sitting in a chair, fewer courses may be utilized. To accommodate a larger fire created through use of greater amounts of fuel, the height of the fire pit 13 may be increased by using one or more additional courses. Also, to comfortably accommodate a deeper fire which may be desired for users who may intend to be standing around the fire pit 13, additional courses may be addded to produce a fire pit 13 of suitable height. The length of the slabs can also vary depending on how large of a fire pit a user desires. For large gatherings of family or friends, a fire pit with a greater permimeter may be desired, or perhaps even a fire pit perimeter formed to have a rectangular footprint, rather than a square footprint, might be more desirable.
A block may be formed, in a preferred embodiment, with concrete poured into elastomeric molds. The concrete generally will be allowed to set for 10-28 days and then be removed from the mold. The molds may be covered with one or more pigments to produce blocks, and ultimately a fire pit or grill, of a desired color or shade. The surface pigment may include, but is not limited to: particles of metal oxide; inorganic pigments; organic pigments; and organic dyes. The molds may also be constructed to achieve a finish on the concrete that mimics the appearance of stone, brick, or decorative mosaic tile. Different coatings are also available for concrete, for example, see U.S. Patent Ser. No. 12/069,734, filed on Feb. 12, 2008, the disclosures of which are herein incorporated by reference.
The blocks may also be formed using air entrained concrete. Air entrained concrete is advantageous for a number of reasons. It results in concrete products having a reduced density. The resulting products also have improved thermal properties. The resulting air entrained blocks provide greater insulation so that the block may be easily handled even when one side had been recently exposed to high heat. The air entrained concrete blocks also have greater resistance to degradation from freezing and thawing of trapped moisture which typically causes expansion and cracking of concrete.
The courses may be assembled to create a stable structure without the use of either mortar, or pins or fasteners of any kind, and unlike prior inventions, they are assembled by using only one joint configuration, which can be incorporated into the elastomeric mold. All of the blocks types, shown in FIGS. 8A through 8K, including a block referred to herein as slab member 30, may be formed with a plurality of notches 15 (FIG. 2A), which are utilized to interlock the blocks, and allow them to dovetail with adjacent blocks. The slab member 30 may generally have a flat upper surface 31 and a flat lower surface 32 which is parallel to upper surface 31. The slab, other than flat upper surface 31 and flat lower surface 32, may take any shape, including, but not limited to an oval, a polygon, or a complex curved surface. One form which slab member 30 may take is that of a rectangular block, whereby the slab member 30, in addition to the upper surface 31 and lower surface 32, may have an inside surface 33 and an outside surface 34, which are generally parallel to each other and are each orthogonal to the upper and lower surfaces, and front end surface 35 and rear end surface 36, which are generally parallel to each other and each of which is orthogonal to the inside and outside surfaces, 33 and 34. Although this illustration will proceed with the rectangular block slab now described, it can also now be clearly seen that the inside surface 33, outside surface 34, front end surface 35, and rear end surface 36 could alternatively be curved, and also could smoothly transition into each other and thus create one continuous surface which could, for example, form an elongated race track shape.
As previously stated, slab member 30 may incorporate a plurality of notches. The notches may comprise many different arrangments, including, but not limited to: a rectangular shaped notch 15; a V-shaped notch with matching V-shaped protrusion and indentation (see FIG. 9B); a cylindrically-shaped notch with a cylindrically-shaped male protrusion and a matching cylindrically-shaped indentation; a hemispherical shaped notch with a protruding male hemisphere and and indented female hemisphere; a conically shaped notch with protruding male conical shape and a female conical indentation; and a complex curve-shaped notch. In a preferred embodiment, notch 15 (see FIG. 2A), may have a first notch side wall 16, a second notch side wall 17, and a notch bearing face 18, where the first notch side wall 16 and the second notch side wall 17 are generally parallel to each other, and orthogonal to the notch bearing face 18.
A preferred embodiment of rectangular slab member 30 may are four notches 15: a first top notch 37 and a second top notch 38, both formed on upper surface 31; and a first bottom notch 39 and a second bottom notch 40, both formed on lower surface 32. The first top notch 37 on the upper surface 31 is located directly opposite the first bottom notch 39 on the lower surface 32, and the second top notch 38 on the upper surface 31 is located directly opposite the second bottom notch 40 on the lower surface 32, so as to form corresponding pairs of notches with one pair on each end of the slab member 30. One pair of notches 15 may be located near the front end surface 35, and the other corresponding pair of notches 15 may be located near the rear end surface 36. In the preferred embodiment, the corresponding pairs of notches are each located roughly the same distance away from end surfaces 35 and 36.
To construct a first course—the bottom course 20 for fire pit 13, a first pair of slab members 30 are positioned parallel to each other with the lower surface 32 of each pair flush with the ground, and spaced apart such that the distance between respective inside surfaces 33 or respective outside surfaces 34 is equal to the distance between first top notch 37 and second top notch 38. The reference to ground herein includes, but is not limited to, an assembly surface comprising soild, grass, a concrete slab, a brick or stone pedestal, etc. A second pair of slab members 30 are positioned parallel to each other and spaced apart so as to allow each of the first and second bottom notches 39 and 40 to dovetail with the first and second top notches 37 and 38 of the first pair of slab members. Successive courses 21 may then be added, with each such course having a primary pair of of slab members 30, and a secondary pair of slab members 30, which are assembled in like fashion to the first and second pairs of slab members 30, by dovetailing to the course immediately below, which may at first be the bottom course 20, and thereafter may be one of the successive courses 21.
Although a successive course 21 of slab members for fire pit 13, as with bottom course 41, will consist of four slab members 30, the fire pit height can also be adjusted by utilizing only one-half of a course, which may be accomplished through the addition of only two additional slab members 30. As illustrated in FIG. 3, the fire pit 13 was assembled using ten slab members, and has two full courses and one half of a course.
The manufacturer will have the option of producing, and the user the option of purchasing, one additional block to tailor the fire pit 13, whereby that block—a plain slab member 80, does not have first and second top notches 37 and 38, but is otherwise formed exactly like slab member 30 having first bottom notch 39 and second bottom notch 40. Use of a pair of plain slab members 80 to add a half of a course permits the fire pit to have a smooth top edge as shown by fire pit 12 in figure 4. Although the dovetail interlocking of the first pair of slab members 30 of the bottom course 20 with the second pair of slab members will result in the second pair of slab members being raised slightly off of the ground, for a fire pit, this would be advantageous in permitting a flow of air to maintain a robust fire, while still serving to contain the fire. The first and second bottom notches, 39 and 40, comprising the first pair of slab members of bottom course 20 (see FIG. 3) could similarly serve to permit air flow. Alternatively, instead of using two of slab members 30 for the first pair of members of the bottom course 20, two plain slab members 80 could be used instead to provide a straight finish as shown in FIG. 4. However, it is worthy of emphasis that a fire pit may be built, and quite easily and without reference to a set of instructions, utilizing multiple copies of slab member 30, and it furthermore could be easily and quickly modified for an increase or reduction in height by adding or removing slab members 30.
The fire pit 13 may also be converted for use as a barbeque grill by adding top grill 5 (FIG. 5), which may, in a preferred embodiment be constructed of angle iron 6 and a grilling surface 7. The grill surface may simply be a traditional metal grate, and be formed of copper; carbon steel; cast iron; stainless steel; bronze; brass; aluminum; high temperature glass; or opaque glazed high impact ceramic. The top grill 5 could be placed directly upon opposite slab members, or alternatively, the slab members could incorporate a plurality of orifices, into which may be inserted dowel pins 9 or a rod, which may protrude into the interior of the fire pit or grill (FIG. 2A), and upon which the top grill 5 may rest.
Additional dowel pins 9 could be inserted into another course so as to support a bottom grill 8. The bottom grill 8 could be formed similar to top grill 5, and also could alternatively incorporate a gas burner to supply heat for cooking, instead of using a fire.
To achieve a barbeque grill which is better adapted for cooking more comfortably and for servicing, a configuration may be easily created whereby the lower front portion of the grill may have a front opening 19 as seen in FIG. 2. The front opening 19 may be created by adding one or more additional courses 22 below the bottom course 20, which in practical terms would dictate that the additional courses 22 were actually the first courses to be assembled with initial placement on the ground. The additional courses 22 may be formed by utilizing a first pair of slab members 30 (or pair of plain slab members 20) and then a different second pair being a set of lateral slab members, which may be comprised of one slab member 30 and two spacer slab members 50. The spacer slab member 50 shown in FIG. 8C may be constructed the same as slab member 30, except that it is significantly shorter and does not have the second top notch 38 and the second bottom notch 40. Assembly of the additional courses may be achieved in similar fashion to the bottom course 20 and successive courses 21, but where the the two spacer slabs 50 replace one of the the two slab members 30 of the second or secondary pairs in a course.
Another feature which may be incorporated into an embodiment of the present invention is a backsplash as shown for barbeque grill 11, in FIG. 2. A plain slab member 80 may be utilized on the top course 23, where the top course is the last of the successive courses 21 added, and where the plain slab member 80 is located opposite to the front opening 19.
A further embodiment of the present invention may include a fume hood 3, one possible embodiment having a fume hood 3 is shown in FIG. 7. The fume hood 3 may rest directly on top of the top grill grate 5, or could be formed to rest on the top course 23. The fume hood 3 may also be mechanically attached to slab members using, though not limited to, dowel pins, masonry screws, or anchors. The fume hood 3 may be constructed of copper, brass, ferrous alloy, bronze, aluminum, or of flame proof composite materials, including, but not limited to, phenolic resin, fiberglass, or carbon fiber reinforced epoxy. The fume hood 3 may also have insulated side handles 4 which are integrally formed or mechanically attached to the fume hood 3.
Another embodiment that incorporates a fume hood is shown in FIG. 1, and may comprise a hood constructed of blocks. In a preferred embodiment, the barbeque grill 10 could be completed through additional assembly of slabs onto the barbeque grill 11 in FIG. 2, by initially removing the back splash that was created through use of plain slab member 20. The top one-half course of the barbeque grill of FIG. 2 was shown, merely to be illustrative of the versatility of the invention, by having one splash slab member 70 and one slab member 30. The most economical and simplest approach would be to use two slab members 30, and disregard the unused second top notch 38, however, a splash slab member 70 could be formed the same as a slab member 30, but without a second top notch 38.
The barbeque grill 10 would require two transition slab members 60, which are shown in FIG. 2A. With the plain slab member 80 back splash having been removed, assembly of the block fume hood may proceed. The assembly process is comparable to that of the additional courses 22 for the grill with the front opening. One or more open hood courses 25 are first added. These open hood courses 25 are comprised of a pair of short slab members 90 (FIG. 8G) and a set of the lateral slab members, which, as for the additional courses 22, are comprised of one slab member 30 and two spacer slab members 50. One or more closed hood courses 26 may be used to create a more vertical fume hood, where the closed hood courses 26 are comprised of a pair of short slab members 90 and a pair of slab members 30. A tapered look to the fume hood may be achieved by using telescoping hood courses 27, which are comprised of a pair of short slab members 90 and a pair of variable length slab members. The variable length slab members are formed the same as the slab member 30, except that the length is shorter, and the first and second top notches, 37 and 38, are positioned father away from the front end surface 35 and rear end surface 36, than the first and second bottom notches, 39 and 40. In a preferred embodiment, three different variable length slab members were utilized, a standard variable length slab member 100, a shorter variable length slab member 110, and a shortest variable length slab member 120. For an aesthetically appealing finish, a pair of short plain slab members 130 may be added to the last telescoping hood courses 27.
The versatility of the block members of the present invention additionally lend the user to custom creating fire pit or barbeque grill accessories, trays or tables, or even integral seats. For example, a table may be formed by utilizing the barbeque grill 11 of FIG. 2 by constructing, adjacent to the grill, a column of blocks 30, as seen in FIG. 2A, but also having spacer slabs 50 for a stable structure. The top course may have a table slab 150 similar to transition slab 60, but with a series of regularly spaced notches that may support a series of plain slab members 80 that create a surface comparable to a redwood picknick table. The grill 22 may have mechanical supports for the series of plain slab members 80, but in a preferred embodiment, one of the slab members 30 of the top course 23 would have be replaced with a table slab member 150.