BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    This invention relates in general to outdoor cooking devices and more particularly relates to an apparatus for producing flavored smoke on an outdoor grill. 
         [0003]    2. Description of the Related Art 
         [0004]    People have long enjoyed the advantages of cooking their meats and vegetables outside over an open heat source. Searing heat traps succulent moisture into meat, slow heat enhances tenderness of meat, smoke of desirable wood varieties enhances the flavor of food, and the combination of heating and smoking can assist in the preservation of food. Furthermore, residual heat and smoke emanating from outside cooking devices are conveniently vented preventing hazard, grease, and soot from afflicting the home. Only a small number of people bear the expense and burden of using authentic open-pit barbecues, traditional brick-pit barbecues, or complex meat-smoking devices. The vast majority of people use a relatively affordable and convenient alternative such as a kettle-type charcoal grill, electric grill, or gas grill. 
         [0005]    While gas grills in particular enjoy an enormous and growing popularity, of themselves they lack the ability to infuse the wood-smoke flavoring to foods they cook. Many gas grill users desire both the convenience and affordability of the gas grill, and the enhancement of food flavor by smoking. Producers of food products have attempted to answer the demand with chemically enhanced ‘smoke-flavored’ products. For most outdoor cooking aficionados these products have not been well-received. More promisingly, producers of outdoor grill products have answered the demand with a variety of ‘smoker boxes’ capable of being implemented in conjunction with the gas grill. 
         [0006]    One useful type of smoker box is placed within the grill, using the heat from the grill to ignite a solid fuel contained in the smoker box such as a desirable variety of wood chip. However, these presently available smoker boxes suffer from several undesirable attributes. For example, presently available smoker boxes are formed from only two pieces: a container with a flat bottom and a lid. The simple flat bottom is ill-fitted to newer models of gas grills using ‘heat bars’ or ‘flavor bars’ and be a cooking hazard if used. 
         [0007]    A further disadvantage of presently available smoker boxes is the inefficient and rapid consumption of fuel. Some smoker boxes are made with non-robust, thermally unsuitable material that may cause them to degrade quickly and combust their solid fuel at a high rate. Also, presently available smoker boxes with only ‘lid’ and ‘container’ can attain only relatively simple ventilation schemes causing too much air to be circulated within the smoker box, often unevenly, leading to rapid consumption of solid fuel and an added undesirable effect of producing more flame and less smoke. During the cooking process, where temperatures vary and oils may drip, the production of flame caused by more direct ventilation designs can result in flare-ups, which diminish the quality of food being cooked and are hazardous. 
         [0008]    Additionally, the attainable ventilation schemes of available smoker boxes poorly address the presence of wood tars in the smoke. Wood tars vaporize during smoking and impart a bitter flavor to the food. 
       SUMMARY OF THE INVENTION 
       [0009]    From the foregoing discussion, it should be apparent that a need exists for an apparatus, system, and method for producing flavored smoke on an outdoor grill. Beneficially, such an apparatus, system, and method would be economical, convenient, allow a low rate of fuel consumption, produce large volumes and high densities of smoke, resist flare-ups, fit securely into a variety of outdoor grills, and reduce the presence of wood tars in the flavored smoke. 
         [0010]    The present invention has been developed in response to the present state of the art, and in particular, in response to the problems and needs in the art that have not yet been fully solved by currently available outdoor grill accessories. Accordingly, the present invention has been developed to provide an apparatus, system, and method for producing flavored smoke on an outdoor grill that overcome many or all of the above-discussed shortcomings in the art. 
         [0011]    An outdoor grill smoker is disclosed for producing flavored smoke on an outdoor grill. The smoker includes a container holding an airborne effluent source and a tortuous path enclosing the container that allows the airborne effluent to vent from the container through the tortuous path. The tortuous path may be formed through layers of non-aligned holes. The holes may be formed in smoker components such as a baffle and a raised lid cover. The tortuous path is devised such that certain ratios between different flow areas and volumes fall within specified ranges as described hereinafter. Container characteristics include angled outer walls to improve circulation of air, heat, and airborne effluent, a reinforcing brace, and a notched bottom designed to allow the smoker to fit into a wide range of outdoor grills. 
         [0012]    A system is disclosed for producing flavored smoke on an outdoor grill. The system includes the outdoor grill, the smoker, and the airborne effluent source. Outdoor grills benefited from the present invention include gas grills, electric grills, and charcoal grills. The smoker may include components such as the container, the baffle, and the raised lid cover. The baffle assists in the suppression of flare-ups and the raised lid cover provides a reservoir for unwanted wood tars to condense out of the airborne effluent. Furthermore, different smoking configurations are achieved by implementing different combinations of components such as using only the raised lid cover and container together, or using only the baffle and container together. The container is designed to hold a variety of airborne effluents such as wood chips and flavored liquids. 
         [0013]    A method is disclosed for producing flavored smoke on an outdoor grill. The method includes providing the outdoor gas grill, providing an item to be smoked, providing the smoker, and providing the airborne effluent source. The method continues by distributing the airborne effluent source into the container, enclosing the container with the baffle, covering the baffle with the raised cover, seating the smoker on a heat bar of the outdoor gas grill, igniting a burner of the gas grill, placing the item to be smoked on a rack of the gas grill, and closing a lid of the gas grill. 
         [0014]    In one example the method continues by checking whether the item to be smoked is done and refreshing the airborne effluent as required. The method concludes by removing the smoked item when done, disengaging the burner, removing the smoker box from the gas grill, and dousing the components of the smoker in water to cool and clean. Smoker components may be equipped with grips, latches, loops, and the like to facilitate the safe removal of the smoker and the convenient disassembly of smoker components. 
         [0015]    Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present invention should be or are in any single embodiment of the invention. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, discussion of the features and advantages, and similar language, throughout this specification may, but do not necessarily, refer to the same embodiment. 
         [0016]    Furthermore, the described features, advantages, and characteristics of the invention may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize that the invention may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the invention. 
         [0017]    These features and advantages of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]    In order that the advantages of the invention will be readily understood, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments that are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings, in which: 
           [0019]      FIG. 1  is a perspective drawing illustrating one embodiment of a system to produce flavored smoke on an outdoor grill in accordance with the present invention; 
           [0020]      FIG. 2  is an illustration depicting one embodiment of a smoker to produce flavored smoke on an outdoor grill in accordance with the present invention; 
           [0021]      FIG. 3  is an illustration depicting one embodiment of smoker flow areas and volume dimensions in accordance with the present invention; and 
           [0022]      FIG. 4  is a schematic flow diagram depicting one embodiment of a method for smoking food on an outdoor gas grill in accordance with the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0023]    It will be readily understood that the components of the present invention, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of the embodiments of the apparatus, system, and method of the present invention, as presented in  FIGS. 1 through 4 , is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. 
         [0024]    Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. 
         [0025]    Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided, such as examples of materials, fasteners, sizes, lengths, widths, shapes, etc., to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention can be practiced without one or more of the specific details, or with other methods, components, materials, etc. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention. 
         [0026]    The schematic flow chart diagrams included herein are generally set forth as logical flow chart diagrams. As such, the depicted order and labeled steps are indicative of one embodiment of the presented method. Other steps and methods may be conceived that are equivalent in function, logic, or effect to one or more steps, or portions thereof, of the illustrated method. Additionally, the format and symbols employed are provided to explain the logical steps of the method and are understood not to limit the scope of the method. Although various arrow types and line types may be employed in the flow chart diagrams, they are understood not to limit the scope of the corresponding method. Indeed, some arrows or other connectors may be used to indicate only the logical flow of the method. For instance, an arrow may indicate a waiting or monitoring period of unspecified duration between enumerated steps of the depicted method. Additionally, the order in which a particular method occurs may or may not strictly adhere to the order of the corresponding steps shown. 
         [0027]      FIG. 1  is a perspective drawing illustrating one embodiment of a system  100  to produce flavored smoke on an outdoor grill  102  in accordance with the present invention. The system  100  may comprise an outdoor gas grill  102  comprising at least one heat bar  104 . In further contemplated embodiments the outdoor grill  102  may comprise one of an electric grill  102  comprising at least one heating element  104  and a charcoal grill  102 . The system  100  further comprises a smoker  106  seated on the at least one heat bar  104 . In one embodiment, the smoker  106  may be manufactured from stainless steel variety  304 H. In other embodiments, the smoker  106  comprises at least one of the group consisting of alternate varieties and grades of stainless steel, metals, metal alloys, ceramics, and/or other materials as determined by one of skill in the art. The desirable characteristics of any material used for manufacture of the smoker  106  are heat conductivity, corrosion resistance, physical durability, and thermal durability. The smoker  106  may be molded, formed, and/or assembled with welds. Furthermore, the smoker  106  may be capable of retaining liquids during use. 
         [0028]    The system  100  further comprises an airborne effluent source  108  disposed within the smoker  106 . For example, the airborne effluent source  108  may be hickory wood chips  108  for smoking a rack of ribs. In another example desirably flavored wood chips may be soaked in water prior to use. In other embodiments considered within the scope of this invention, the airborne effluent source  108  may be a flavored liquid such as beer and the like. For example, one half of the smoker  106  may contain hickory wood chips  108 , while the other half contains beer  108 . The outdoor grill  102  may further comprise a lid  110  capable of trapping heat and smoke within the grill  102 , a rack  112  to suspend items over the heat source  104  and smoker  106 . In some embodiments the grill  102  may be equipped with an igniter  114  and a control knob  116  that may be used to control and/or extinguish heat emanating from the heat bar  104 . 
         [0029]      FIG. 2  is an illustration depicting one embodiment of a smoker to produce flavored smoke on an outdoor grill in accordance with the present invention. The smoker  106  comprises a container  202  holding the effluent source  108 . The container  202  comprises angled outer walls  204 . In one embodiment, the angled outer walls  204  may be about 10 degrees from the vertical. In alternate embodiments, the angled outer walls  204  comprise an angle between about 5 degrees and 45 degrees from the vertical. The outer walls  204  are angled for a given embodiment to improve the flow of heat and air through the container  108 . The container  202  further comprises a notched bottom  206  comprising a squared angle of about 45 degrees. The notched bottom  206  is configured to straddle a heat bar  104  in the outdoor grill  102 . The notched bottom  206  forms a pinnacled surface inside the container  202  running down the length of the container  202  that acts to direct the airborne effluent and heat up through the center of the smoker  106 . The container  202  further comprises a reinforcing brace  208  to increase the structural rigidity and thermal durability of the container  202 . 
         [0030]    The smoker  106  may further comprise a baffle  210 . The baffle  210  comprises U a baffle lid  212  that rests over the edges of the container  202  forming a partial seal. The baffle  210  further comprises a baffle plate  214  comprising a plurality of baffle holes  216  and a baffle volume  218  configured between the baffle plate  214  and the baffle lid  212 . The term “holes” is used for convenience throughout the description. In alternate embodiments, the holes may be slits, screens, hatches, or other devices known in the art to provide a flow area. The lid  212  further comprises lid holes  220  (not visible) forming the bottom of and venting into the baffle volume  218 . The lid holes  220  are non-aligned with the baffle holes  216  comprising a tortuous path for heat and the airborne effluent  108  flowing up through the smoker  106 . The baffle plate  214  may comprise an extractor device  222  facilitating the removal of the baffle  210  from the container  202 . In one embodiment, the extractor device  222  is a handle  222 . In alternate embodiments, the extractor device  222  may be at least one slit, hole, loop or other device facilitating the disassembly of the smoker  106  components and usefully interface with at least one of a grill mitt, channel locks, BBQ fork, tongs, and the like. 
         [0031]    The smoker  106  may further comprise a raised cover  224 . The raised cover  224  comprises a holding volume  226  collecting the airborne effluent emanating from the baffle  210  before allowing the airborne effluent to cascade down the sloped sides of the holding volume  226  to dispersing holes  216 . For example, when the airborne effluent is wood smoke the steps of collecting the smoke in the holding volume  226 , allowing the smoke to cascade down the sides of the raised cover  224 , and finally dispersing the smoke through the dispersing holes  216  results in a smoother, cleaner, and better tasting smoke flavor as the heavier wood tar particulates condense out of the smoke and are deposited onto the sides of the raised cover  224 . The raised cover  224  may further comprise at least one extractor device  222 . 
         [0032]      FIG. 3  is an illustration depicting one embodiment of smoker  106  flow areas  302  and volume dimensions  304  in accordance with the present invention. The smoker  106  comprises a first flow area (F 1 )  302 A, and a second flow area (F 2 )  302 B. The first flow area  302 A comprises the sum of the area of the holes at the bottom of the baffle volume  304 A and the second flow area  302 B comprises the sum of the area of the holes at the top of the baffle volume  304 A. The ratio F 1 /F 2  affects the smoke quality. For example, the ratio F 1 /F 2  controls the flow velocity through the various flow areas  302 , affects the airborne effluent residence time in the baffle volume  304 A, and interacts with the flame in the container  202 . In one embodiment, the ratio of F 1 /F 2  may be a value of about 1.75. In alternate embodiments, the ratio of F 1 /F 2  may be a value between about 1.2 and 2.5. A value of F 1 /F 2  greater than 1 indicates that the flow velocity through the flow area F 2    302 B is higher than the flow velocity through the flow area F 1    302 A. 
         [0033]    The smoker  106  may further comprise a third flow area (F 3 )  302 C. The third flow area F 3    302 C comprises the sum of the flow areas at the top of the raised cover  224 . The ratio F 2 /F 3  affects the smoke quality. For example, the ratio F 2 /F 3  controls the flow velocity through the various flow areas  302  and affects the airborne effluent residence time in the raised cover  224 . The ratio F 2 /F 3  may be a value of about 0.58. In other embodiments, the ratio of F 2 /F 3  may be a value between about 0.2 and 0.8. A value of F 2 /F 3  less than 1 indicates that the flow velocity through the flow area F 3    302 C is less than the flow velocity through the flow area F 2    302 B. 
         [0034]    The smoker  106  further comprises a first volume (V 1 )  304 A. The first volume  304 A comprises a volume disposed between the flow areas  302 A and  302 B. The ratio V 1 /F 2  affects the smoke quality. For example, the ratio V 1 /F 2  may determine residence times for airborne effluents and smoke densities. In one embodiment of the current invention, the ratio V 1 /F 2  may be a value of about 360 mm. In alternate embodiments of the current invention, the ratio V 1 /F 2  may be a value between about 90 mm and 700 mm. The larger the volume is compared to the flow area translates into a longer residence time for an airborne effluent and a higher smoke density. 
         [0035]    The smoker  106  may further comprise a second volume (V 2 )  304 B. The second volume  304 B comprises the volume  304 B above the dispersing holes  216 . The volume  304 B acts as a holding volume for smoke allowing the smoke time to contact the raised cover  224  walls and leaving the heavier wood tar deposits on the wall surface. In one embodiment, the ratio of V 2 /F 3  may be about 370 mm. In other embodiments, the ratio of V 2 /F 3  may be between about 90 mm and 750 mm. The larger the volume is compared to the flow area translates into a longer residence time for an airborne effluent and a higher smoke density. 
         [0036]    The smoker  106  may comprise a third volume (V 3 ) corresponding to volumes  304 B and  304 C. The third volume comprises the entire volume under the raised cover  224 . In one embodiment, the ratio V 3 /F 3  may be about 500 mm. In other embodiments, the ratio V 3 /F 3  may be between about 125 mm and 1000 mm. The larger the volume is compared to the flow area translates into a longer residence time for an airborne effluent and a higher smoke density. Ratios of flow areas  302  and volumes  304  are meant to be illustrative of the process by which an airborne effluent flows through a tortuous path within the smoker  106 . One of skill in the art may manufacture a variety of smoker  106  configurations using these values and mathematical ratios as guidelines. 
         [0037]      FIG. 4  is a schematic flow diagram depicting one embodiment of a method  400  for smoking food on an outdoor gas grill in accordance with the present invention. The method  400  comprises providing  402  an outdoor gas grill and providing  404  an item to be smoked. In one embodiment the method  400  includes providing  406  a smoker comprising a container, a baffle, and a raised cover. The method  400  further comprises providing  408  an airborne effluent source. In one example, providing  408  the airborne effluent comprises soaking wood chips for a time in water prior to distributing  410  the airborne effluent source into the container. Saturating wood chips with moisture causes the wood chips to smolder more slowly and facilitates a more consistent source of smoke. In one embodiment of the present invention the method  400  continues by enclosing  412  the container with the baffle, covering  414  the baffle with the raised cover, and seating  416  the smoker on a heat bar of the gas grill. In further embodiments of the present invention, alternate cooking configurations may be achieved using only the container and baffle, or only the container and raised cover. 
         [0038]    The method  400  may further include igniting  418  at least one burner of the gas grill, placing  420  the item to be smoke on a rack of the gas grill, and closing  422  a lid of the gas grill to substantially trap the airborne effluent therein. In one example the method  400  may include checking  424  to discover if the item to be smoked is done, and checking  426  to discover if more airborne effluent is required. Should more airborne effluent be required the method  400  may include refreshing  428  the airborne effluent until the item to be smoke is done. The method  400  may conclude by removing  430  the item to be smoked, disengaging  432  the burner, removing  434  the smoker from the gas grill, and dousing  436  the raised cover, baffle, and container in water. 
         [0039]    The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
An apparatus is disclosed for producing flavored smoke on an outdoor grill. The apparatus comprises a smoker that includes a container and a tortuous path. The tortuous path is devised such that certain ratios between different flow areas and volumes fall within specified ranges. Container characteristics include angled outer walls, reinforcing brace, and notched bottom. The container holds an airborne effluent source with the tortuous path enclosing the container. The tortuous path is formed through layers of non-aligned openings that allow the airborne effluent to vent from the container. The smoker may include a baffle and a raised lid cover. The raised lid cover is formed to collect undesirable wood tars.