Abstract:
An apparatus is adapted to be placed over an open flame source and employed as a grilling surface for cooking. The apparatus further has a flat grilling platform, a support frame, and a hoist assembly. The grilling platform is operatively suspended from the support frame by the hoist assembly such that the hoist assembly can raise and lower the grilling platform as desired. An embodiment of the apparatus provides for a fire box to facilitate construction and containment of a fire for use with the apparatus.

Description:
RELATED APPLICATIONS 
     The present invention was first described in and claims the benefit of U.S. Provisional Application No. 61/935,571, filed Feb. 4, 2014, the entire disclosures of which are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to an adjustable platform adapted to be placed over an open flame source and employed as a grilling surface for cooking. 
     BACKGROUND OF THE INVENTION 
     Whether cooked on a grill or over a campfire, food cooked outdoors just always seems to taste better than food cooked indoors. It could be the outdoor air, cooking procedures, or a hundred other variables, but one&#39;s taste buds just seem to explode. Many people who cook outdoors as part of a camping trip use a grill, which must be brought along for the trip including fuel, legs, cooking surfaces, and the like. Even those who cook on a campfire must bring a complicated stand with multiple legs that seem to collapse, and are never long enough to place food high above a fire. Another option is a complicated tripod arrangement which is difficult to set up, and then can only be used with a kettle. All of these solutions are either complicated, difficult to store, hard to transport, and/or require many solutions depending on the type of food being cooked. Accordingly, there exists a need for a means by which virtually any type of food can be cooked over a campfire without the disadvantages as described above. The development of the adjustable grilling platform fulfills this need. 
     The apparatus is used to assist with cooking over an open fire. There are two vertical supports facilitating slidable engagement with a grated cooking surface. The cooking surface is held in position by two (2) cables that are routed around pulleys disposed at a top of the apparatus. These cables then terminate at a hoist assembly, which enables selective hoisting and lowering of the cooking surface. The slidable engagement of the cooking surface with the vertical supports also provides for locking pins to hold the cooking surface at a desired height. An alternative embodiment provides for a fire box in which a fire may be constructed and contained. 
     Prior art in this field consists of simple posts that have cooking grates attached thereto. Some of these posts have pivoting arms connecting the cooking grate. Other prior art posts include pivoting arms with clamping apparatuses to attach pans, plates, or grates. Some prior art devices are more elaborate and consist of stands with height adjustable cooking surfaces, but these cooking surfaces are not stabilized from swinging and swaying, as is the cooking surface of the present invention. There are other prior art devices that have stabilized adjustable cooking surfaces, but these are height adjustable by telescoping support legs. With these telescoping legs, it proves difficult to adjust the cooking surface when food is placed thereupon and when there is a fire beneath the device. Furthermore, this type of adjustment means impedes the ability to perform large scale cooking because it does not lend itself to easy height adjustment with heavy items. 
     It is an objective of the present invention to provide a stable and sturdy cooking surface for cooking foods over an open fire. 
     It is a further objective of the present invention to provide a height adjustment mechanism for the cooking surface to accommodate fires of variable height and differing cooking temperatures dictated by certain cooking recipes. 
     It is a further objective of the present invention to provide a cooking surface with a stand that is modular and easily disassembled for easy transport and set up 
     It is a further objective of the present invention to provide a cooking surface that is stabilized such that it neither swings when bumped nor sways in the wind. 
     It is a further objective of the present invention to provide a cooking surface that is adjustable without disrupting the food placed thereupon, thereby evenly and smoothly hoisting and lowering the cooking surface. 
     It is a further objective of the present invention to enable hoisting and lowering the cooking surface with a fire occurring beneath the device and while the food is being cooked. 
     It is a further objective of the present invention to provide a height adjustable cooking surface that facilitates heavy duty cooking of large meals while not detracting from portability and ease of use. 
     It is a further objective of the present invention to provide a fire box as a means to construct and contain an open fire, if desired. 
     It is a further objective of the present invention to provide a plurality of skewers to enable broiling of meat impaled thereupon. 
     SUMMARY OF THE INVENTION 
     The apparatus comprises two (2) leg assemblies supporting a platform assembly. The platform assembly is configured to slidably traverse the leg assemblies to provide a height adjusting cooking surface. There is also a hoist assembly that is used to assist a user with adjusting the height of the cooking surface. The platform assembly is preferably a grated surface to facilitate broiling, heat transfer, convective flow, and drainage of cooked fluids from the meat placed upon it. A plurality of skewers extends from at least one (1) edge of the platform upon which food items may be impaled for cooking. 
     A top portion of the apparatus has an upper bar assembly that is removable. This upper bar assembly is equipped with a first, second, and third pulley. A first cable extends from the hoist assembly and is routed through the first pulley, the third pulley, and then attached to the platform. A second cable extends from the hoist assembly and is routed through the second pulley and then attached to the platform. Actuation of the hoist assembly acts upon each cable simultaneously and either hoists or lowers the platform. The platform is further provided with locking pins to enable a user to secure the platform at a desired height. 
     An alternative embodiment of the invention provides for a fire box in which a fire can be constructed and contained for use with the apparatus. 
     Furthermore, the described features and advantages of the disclosure may be combined in various manners and embodiments as one skilled in the relevant art will recognize. The disclosure can be practiced without one (1) or more of the features and advantages described in a particular embodiment. 
     Further advantages of the present disclosure will become apparent from a consideration of the drawings and ensuing description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The advantages and features of the present disclosure will become better understood with reference to the following more detailed description and claims taken in conjunction with the accompanying drawings, in which like elements are identified with like symbols, and in which: 
         FIG. 1  is a perspective view of an adjustable grilling platform  10  in accordance with the preferred embodiment of the present invention; 
         FIG. 2  is a detail view of the platform assembly  30  of the adjustable grilling platform  10  in accordance with the preferred embodiment of the present invention; 
         FIG. 3  is an exploded view of the adjustable grilling platform  10  in accordance with the preferred embodiment of the present invention; 
         FIG. 4  is a detail view of a wire rope guide  86  of the adjustable grilling platform  10  in accordance with the preferred embodiment of the present invention; and, 
         FIG. 5  is a perspective view of the adjustable grilling platform  10  illustrated with a fire box  130  in accordance with an alternate embodiment of the present invention. 
     
    
    
     DESCRIPTIVE KEY 
     
         
         
           
               10  adjustable grilling platform 
               20  leg assembly 
               22  stabilizer 
               24  upright 
               26  upper end 
               28  winch aperture 
               30  platform assembly 
               32  frame 
               34  first tube 
               36  second tube 
               38  lateral tube 
               42  grate 
               44  skewer 
               45  angle 
               46  arm 
               48  guide 
               52  lock pin 
               53  tee handle 
               54  threaded aperture 
               56  eyebolt 
               58  retainer 
               60  upper bar assembly 
               62  upper bar 
               64  insert tube 
               66  first pulley 
               67  first pulley bracket 
               68  second pulley 
               69  second pulley bracket 
               72  third pulley 
               73  third pulley bracket 
               74  mounting pin 
               76  pin retainer 
               78  bracket fastener 
               79  threaded retainer 
               80  hoist assembly 
               82  winch 
               84  drum 
               86  wire rope guide 
               88  drum latch mechanism 
               92  crank 
               94  handle 
               96  winch fastener 
               102  first cable 
               104  second cable 
               106  cable loop 
               112  snap hook 
               114  eye 
               118  hook 
               122  cable clamp 
               130  fire box 
               132  sidewall 
               134  bottom 
               138  coal bed 
               142  handle 
           
         
       
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The best mode for carrying out the invention is presented in terms of its preferred embodiment, herein depicted within  FIGS. 1 through 4 , with an alternate embodiment within  FIG. 5 . However, the invention is not limited to the described embodiment, and a person skilled in the art will appreciate that many other embodiments of the invention are possible without deviating from the basic concept of the invention and that any such work around will also fall under the scope of this invention It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and only one particular configuration shall be shown and described for purposes of clarity and disclosure and not by way of limitation of scope. 
     The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items. 
     The present invention describes an adjustable grilling platform (herein referred to as the “apparatus”)  10 , which provides an adjustable height surface for cooking foods over an open fire when the source of the heat may be at a variable height. 
     Referring now to  FIG. 1 , a perspective view, and  FIG. 3 , an exploded view, of the apparatus  10  according to the preferred embodiment of the present invention, is disclosed. The apparatus  10  includes a platform assembly  30  supported on two (2) leg assemblies  20 , a removable upper bar assembly  60 , and a hoist assembly  80 . Each leg assembly  20  is configured generally as an inverted “T” with an upright  24  attached perpendicularly to the midpoint of a horizontal stabilizer  22 . The upright  24  and the stabilizer  22  preferably compose square steel tubes which are coated, or plated, with a material to inhibit corrosion. An upper end  26  of the upright  24  is left open to accept an insert tube  64  of the upper bar assembly  60  to be slid into the upper end  26 . Disposed along an upper side of each upright is a winch aperture  28 . Only the winch aperture  28  on one (1) upright will be utilized for the attachment of a winch  82 , however, a greater uniformity is achieved when a winch aperture  28  is included in both uprights  24 . 
     The platform assembly  30 , as more clearly seen in  FIG. 2 , preferably comprises a planar, rectangular frame  32  with guides  48  attached to arms  46  on each side. The frame  32  is configured to be two (2) parallel, opposing first tubes  34  welded to two (2) perpendicular opposing second tubes  36 . The first tubes  34  and the second tubes are preferably steel tubes with a square or rectangular cross-section. Other materials, and other shapes, may be used in the fabrication of the frame  32 . The ends of all first tubes  34  and all second tubes  36  are preferably cut on a forty five degree (45°) miter and welded together such that the internal surfaces of all tubes  34  and  36  are sealed. A plurality of lateral tubes  38  are uniformly positioned between the first tubes  34  and continuously welded, with appropriate bead, around the perimeter of each end to permanently secure the lateral tubes  38 . The lateral tubes  38  span the distance between the first tubes  34 . The grate  42  is preferably a piece of expanded metal sheeting configured to be attached to the upper surface of the frame  32 . Other materials, such as a plurality of rods, may be used in the construction of the grate  42  without limiting the scope of the apparatus  10 . 
     A plurality of skewers  44  is attached to at least one (1) of the first tubes  24  at a non-zero angle  45 . The skewer  44  is a small diameter metal rod upon which an item of food may be impaled for cooking. The preferred angle  45  of orientation for the skewers  44  would be within a range from thirty degrees (30°) to forty five degrees (45°) with respect to the horizontal. The first tube  24  to which the skewers  44  are attached will be defined as the back, or rear, of the platform assembly  30 . 
     Attached to each side of the rectangular frame  32 , preferably by welding, is an arm  46 . The arms  46  are square steel tubes configured to be attached at a first end to an exterior side of each second tube  36 . Attached to a second end of each arm  46  is a guide  48 . The guide  48  is a sleeve configured to have a profile necessary to encompass a single upright  24  of the leg assembly  20 . The guides  48  restrict the lateral movement of the platform assembly  30  as the platform assembly  30  is raised or lowered above a fire. 
     Disposed in the upper and the lower faces of each arm  46  is an aperture (not shown) into which an eyebolt  56  is fastened. The eyebolt  56  is configured with a closed eye and a threaded shank. The eyebolt  56  may be provided with a shoulder between the eye and the shank; however this is not a defining point of the apparatus  10 . The eyebolts  56  are secured in each arm  46  by means of a threaded retainer  58 . 
     Disposed along a front side of at least one (1) of the guides  48  is a threaded aperture  54  into which a locking pin is inserted. The constituent material of the guide  48  may be of a sufficient thickness to permit an adequate thread depth, or alternately a threaded retainer may be attached to the guide  48  over an aperture. The locking pin  52  is configured to be a threaded rod to which a tee handle  53  is attached to increase the moment arm, thus permitting more torque to be developed on the locking pin  52 . The locking pin  52  is intended to prevent relative motion between the guide  48  and an upright  24  inserted therein. 
     The upper bar assembly  60  includes an upper tube  62  having insert tubes  64  attached perpendicularly at either end. The upper tube  62  and the insert tubes  64  preferably comprise square tubing of a size which can be inserted into the upper ends  26  of the uprights  24  of the leg assembly  20 . The ends of the upper tube  62  and the conjoined ends of the insert tubes  64  are preferably cut on a forty five degree (45°) miter and welded together. 
     Disposed along the upper bar  62  are a first pulley  66  configured to be mounted in a first pulley bracket  67 , a second pulley  68  mounted in a second pulley bracket  69 , and a third pulley  72  mounted a third pulley bracket  73 . Each of the pulleys  66 ,  68 , and  72  is retained in the respective brackets  67 ,  69 , and  73  by means of mounting pin  74  which is in each case secured with a pin retainer  76 . The mounting pins  74  also act as axles for each of the pulleys  66 ,  68 , and  72  to allow rotational motion. The first pulley bracket  67  is similar to the second pulley bracket  69 . The first pulley bracket  67  is attached to a first end of the upper bar  62  by means of at least one (1) bracket fastener  78  inserted through the first pulley bracket  67  and an aperture (not shown) in the upper bar  62  and retained with a threaded retainer  79 . The second pulley bracket  69  is attached in a generally similar manner to a second end of the upper bar  62 . The third pulley bracket  73  is attached to the upper bar  62  in proximity to, but laterally opposed to, the second pulley bracket  69 . This third pulley bracket  73  is configured to retain the third pulley  72  at a somewhat greater elevation above the upper bar  62  than either the first pulley  66  or the second pulley  68 . 
     The hoist assembly  80  includes a winch  82 , a first cable  102 , and a second cable  104 . The winch  82  is attached to an upright  24  by means of a threaded winch fastener  96  inserted through a winch aperture  28  and the winch  82 . The winch  82  can be any manually operated hoisting mechanism having a crank  92 , which can be manipulated by means of a handle  94 , to directly, or through a series of reduction gears, turn a drum  84 , or other reel mechanism, to gather the first ends of the first cable  102  and the second cable  104  simultaneously in order to shorten the operable length of those cables  102  and  104 . The winch  82  is preferably configured to have a wire rope guide  86  disposed on the drum  84  as seen in  FIG. 4 . The wire rope guide  86  is a spiral groove, or a pair of spiral grooves, formed into the material of the drum  84  which cause the cables  102  and  104  to align in sequential adjacent wraps as the winch  82  is turned. The winch  82  is also configured to have a drum latch mechanism  88  comprising a spring-biased latch engaging in a toothed wheel to retain the cables  102  and  104  in a preferred position to maintain the platform assembly  30  at a desired height. 
     The first cable  102  and the second cable  104  are each configured to have a cable loop  106  at a second end. The first cable  102  is inserted through the eye  114  of a snap hook  112  and doubled over on itself to form the cable loop  106  and secured in that position by means of at least one (1) cable clamp  122 . The second cable  104  is configured similarly with another snap hook  112  engaged in a cable loop  106 . The second end of first cable  102  is extended from the drum  84  of the winch  82  and routed over the third pulley  72  and then the first pulley  66  and then is attached to the farthest eyebolt  56  in the platform assembly  30  by means of engaging the hook  118  of the snap hook  112  into the eyebolt  56 . The second end of the second cable  104  is similarly extended from the drum  84  of the winch  82  and routed over the second pulley  68  and then is attached to the nearest eyebolt  56  in the platform assembly  30  by means of engaging the hook  118  of the snap hook  112  into the eyebolt  56 . 
     Referring now to  FIG. 5 , a perspective view of the apparatus  10 , showing a fire box  130 , according to an alternate embodiment of the present invention, is disclosed. This embodiment is envisioned to use the platform  10  as described above and illustrated in  FIGS. 1 through 4 . A fire box  130  is alternately provided for the apparatus  10  in the eventuality that a fire pit, or other such camp fire, is not conveniently available. The fire box  130  is configured to be a rectangular polyhedron having four (4) planar peripheral sidewalls  132  meeting at a bottom  134  to form an interior. The sidewalls  132  and the bottom  134  are preferably composed of steel plate continuously welded along all conjoined edges. Suspended from the interior of the sidewalls  132  is a coal bed  138  upon which a fire is built. The coal bed  138  preferably comprises expanded sheet metal. The fire box  130  is provided with at least one (1) handle  142  on an exterior of at least one (1) of the narrow sides for manipulating the fire box  130 . 
     It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and only one particular configuration shall be shown and described for purposes of clarity and disclosure and not by way of limitation of scope. 
     The preferred embodiment of the present invention can be utilized in a simple and straightforward manner with little or no training. After initial purchase or acquisition of the apparatus  10 , it would be assembled as indicated in  FIG. 1 , or alternately as shown in  FIG. 5  with a fire box  130 . 
     The method of installing and utilizing the apparatus  10  may be achieved by performing the following steps: acquiring a model of the apparatus  10 ; inserting the uprights  24  of each leg assembly  20  into the guides  48  of the platform assembly  30 ; tightening the locking pins  52 ; sliding the insert tubes  64  of the upper bar assembly  60  into the upper ends  26  of the uprights  24 ; attaching the winch  82  to the upright  24  in closest proximity to the second pulley  68  and the third pulley  72 ; threading the first cable  102  over the third pulley  72  and then over the first pulley  66 ; attaching the hook  118  of the snap hook  112  into the eyebolt  56  on the far side of the platform assembly  30 ; threading the second cable  104  over the second pulley  68 ; attaching the hook  118  of the snap hook  112  into the eyebolt  56  on the near side of the platform assembly  30 ; position the apparatus  30  over a fire pit or camp fire; and, placing food on the upper surface of the grate  42  of the platform assembly  30  or on the skewers  44  and cooking the food to the desired doneness. Alternately if a fire pit or other camp fire is not available a fire can be started in the fire box  130  by placing the desired fuel on the coal bed  138 ; igniting the fuel; and, placing the fire box  130  under the platform assembly  30  between the leg assemblies  20 . 
     The foregoing descriptions of specific embodiments have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit to the precise forms disclosed and many modifications and variations are possible in light of the above teachings. The embodiments were chosen and described in order to best explain principles and practical application to enable others skilled in the art to best utilize the various embodiments with various modifications as are suited to the particular use contemplated.