CN110353520B

CN110353520B - Oven with cold smoke baking mode

Info

Publication number: CN110353520B
Application number: CN201910235096.2A
Authority: CN
Inventors: M·V·科尔斯顿; D·A·C·阿尔滕里特; D·W·斯拉德
Original assignee: Traeger Pellet Grills Inc
Current assignee: Traeger Pellet Grills Inc
Priority date: 2018-03-26
Filing date: 2019-03-26
Publication date: 2025-01-28
Anticipated expiration: 2039-03-26
Also published as: CN110353520A; AU2019202074A1; CA3037934A1

Abstract

A grilling device includes: an auger system, a heating element, a blower, and a temperature control system. The temperature control system includes at least a first temperature sensor in a fire cup and a second temperature sensor in a cooking chamber above the fire cup. The heating element can also serve as the first temperature sensor. A method of controlling the temperature of an oven may include receiving temperature feedback information from one or more temperature sensors and adjusting the power provided to the auger system, the heating element, and the blower. The temperature control system produces cool smoke caused by the combustion of lignin in a solid wood fuel while minimizing the temperature in the cooking chamber.

Description

Oven adopting cold smoke baking mode

Cross Reference to Related Applications

The present application claims priority from U.S. provisional patent application Ser. No.62/648,213 filed on day 3 and 26 of 2018. This application also claims priority from U.S. provisional patent application Ser. No.62/819,430, filed on 3 months 15 of 2019. Each of the above applications is incorporated by reference into the present application.

Technical Field

The present invention relates generally to systems, methods, and devices for grilling and heating food items.

Background

Many people prepare food on grilling devices such as solid fuel ovens, smoke racks, gas ovens, and the like. The taste, moisture, texture and other qualities of the food prepared by the user in such a device depend on a number of factors. Of course, one of the most important factors is the temperature at which the user cooks the food. In the case of solid fuel barbecue apparatus such as a hob, it is important for the user to quickly and accurately control the temperature of the smoke generated by the ignition of the solid fuel inside the hob. That is, exposing the food to overheated or overcooled smoke may result in the food having an undesirable taste, moisture, tenderness, or other undesirable quality.

In addition, the ideal smoke temperature for a user to cook food in the smoke cage varies depending on the type of solid fuel the user uses and the type of food the user is preparing. For example, a smoke produced by igniting solid fuel in a smoke cage has a unique taste, depending on the type of solid fuel that produces the smoke. One type of solid fuel may produce smoke having one taste, while another type of solid fuel may produce smoke having a different taste. The user may need to maintain each type of taste at a unique temperature to most effectively transfer that taste into the food. In many cases, a user may want a low temperature smoke (or "cold smoke") to produce an optimal taste. In some cases, the user may want high temperature smoke to cook food most efficiently.

Furthermore, the various foods cooked by the user may each require a unique temperature or combination of temperatures. For example, a user may need to expose steak to different smoke temperatures than certain vegetables even if the user uses the same type of solid fuel in both cases. Furthermore, the user may need to change the temperature of the smoke over time. For example, a user may want to smoke a certain type of meat at a high temperature to burn the outside of the meat, and then gradually decrease the temperature. Also, for example, a user may want to smoke certain types of vegetables starting at a low temperature and then increasing the temperature at the end to embrittle the outer layers of the vegetables. These different temperatures and temperature combinations are referred to as "barbecue modes".

One disadvantage of the smoke rack is the increased warm-up time required for the smoke rack as compared to other barbecue apparatus using gas or electric burners. Often, current smoke racks lack the functionality and control systems necessary to quickly and accurately obtain various temperatures and barbecue modes to pick and select the barbecue mode based on the type of solid fuel being used by the user and the type of food being prepared by the user. In addition, while current smoke racks often provide basic temperature control capability, they often require long warm-up and temperature transition times.

Interestingly, the generation of cold smoke often increases the required warm-up time compared to the time required to generate hotter smoke. This is because typical temperature control systems in smoke racks have a lag time built into the feedback loop of the control system. For example, in a typical temperature control system feedback loop, a temperature sensor that measures the temperature of the smoke in the cooking chamber of the smoke holder communicates temperature feedback information to the processor. Thus, the processor increases or decreases the rate at which the feeder introduces fuel into the combustion chamber (or "firebox") of the barbecue device to increase or decrease the temperature accordingly.

However, when a user desires a low smoke temperature, the runaway flame (generated by self-sustaining combustion of the solid fuel fed into the fire pot during warm-up) may become too hot before the temperature sensor relays temperature feedback information back to the processor to correct the temperature overshoot. When this occurs, even if the fuel feeder completely stops supplying fuel into the fire pot, the user must wait for the existing fuel to decrease and reduce the temperature, which takes time. In many cases, cold smoke is generated from uncontrolled combustion of smoldering fuel rather than fuel that generates a hot flame. Often, waiting for the fuel to decrease to smoldering after the flame is generated in order to correct the temperature control system overshoot and generate the required cold smoke takes a longer time than the temperature in the fire pot to obtain a hotter smoke.

Accordingly, there are many challenges and problems in the field of smoke racks and barbecue equipment that need to be addressed.

Disclosure of Invention

Various embodiments of the present application include systems, methods, and apparatus for generating cold smoke in an oven, such as a barbecue smoke generator, as well as components and/or sub-components thereof. These components and/or sub-components enable a user to generate smoke at low temperatures for extended periods of time within the main oven or "cooking chamber" of the barbecue apparatus. For example, a user can generate smoke and various air temperatures in the cooking chamber of an oven in a "closed loop" environment at or below 150F for several hours at a time. Additionally or alternatively, the user can generate smoke and various air temperatures in the cooking chamber of the barbecue apparatus at or below 120°f, at or below 100°f, at or below 90°f, and/or at or below 80°f, as described in more detail herein.

In accordance with these and other aspects, a grilling device in accordance with one embodiment includes a main oven having a cooking chamber for cooking food, and a screw feeder system integrated with the main oven for delivering wood fuel. The barbecue apparatus also includes a fire pot connected to the screw feeder system, the fire pot having an interior space for receiving wood fuel dispensed by the screw feeder system, and a heating element powered by a power source, the heating element providing heat to the interior space of the fire pot.

In addition, certain embodiments of the grilling device include a blower powered by a power source, the blower providing oxygen to an interior space of the firebox, and a first temperature sensor disposed proximate the firebox, a second temperature sensor disposed proximate the cooking chamber, and a digital controller. Such an embodiment of the barbecue apparatus is configured in association with the digital controller, the first and second temperature sensors, the heating element, and the blower to burn fuel in the firebox.

In one or more embodiments, a method for generating cold smoke in a grilling device for cooking food includes providing a grilling device as previously described including a firebox, a heating element, a blower, a first temperature sensor, a power source, and a processor. The method further includes igniting the solid fuel within the interior space of the cupping jar by activating the heating element and sensing a temperature within the cupping jar with the first temperature sensor and communicating cupping jar temperature information to the processor. In addition, the method includes adjusting the electrical energy supplied to the heating element and the blower based on the fire pot temperature information to cause the temperature generated within the fire pot to exceed 500°f. This is accomplished while maintaining a second temperature in a cooking chamber of a barbecue apparatus disposed above the firebox below about 150°f for a period of at least 5 minutes.

In at least one embodiment of the present application, a barbecue apparatus for producing cold smoke for cooking or heating food includes a cooking chamber, a firebox having an interior space, a heating element configured to ignite fuel residing within the interior space of the firebox, a blower configured to circulate oxygen into the interior space of the firebox, and a power source configured to provide electrical energy in the barbecue apparatus. The grilling device further includes a processor and a memory containing computer executable instructions.

In such embodiments, the computer executable instructions, when executed, ignite the fuel within the interior space of the firepot by providing a first amount of electrical energy from the power source to the heating element. The instructions then provide a second amount of electrical energy to the heating element, the second amount of electrical energy being less than the first amount of electrical energy. The instructions then provide a second amount of electrical energy to the heating element, the second amount of electrical energy being less than the first amount of electrical energy.

In this embodiment, the instructions then convert the resistance measurements to fire pot temperature information at the processor and adjust the power supplied to the heating element and blower based on the fire pot temperature information. This adjustment prevents the fuel from entering a continuous combustion state and maintains the temperature within the cooking chamber at about 150°f or less for at least five minutes.

Additional features and advantages of exemplary implementations of the application will be set forth in the detailed description which follows, and in part will be apparent from the description or may be learned by practice of the exemplary implementations. The features and advantages of the applications may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims. These and other features will become more fully apparent from the following detailed description and appended claims, or may be learned by the practice of these exemplary applications as set forth hereinafter.

Drawings

In order to describe the manner in which the above-recited and other advantages and features of the invention can be obtained, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. It is appreciated that the drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The present invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

FIG. 1 is a diagram of an embodiment of a barbecue apparatus according to the present application;

FIG. 2 depicts an embodiment of the screw feeder system shown in the oven of FIG. 1, including a screw feeder, a firebox, a blower, and a heating element according to the present application;

FIG. 3 depicts a cross-sectional view of an embodiment of a screw feeder system according to the present application feeding fuel into a fire pot for combustion;

FIG. 4 depicts a cross-sectional view of an embodiment of a fire pot according to the present application with a heating element extending therein;

FIG. 5 depicts a cross-sectional view of an embodiment of a fire pot with a non-contact heating element according to the present application;

FIG. 6 shows a schematic diagram of an embodiment of a temperature control system of a barbecue apparatus according to the present application;

FIG. 7A illustrates a flowchart outlining one embodiment of a method for rapidly implementing a cold smoke barbecue mode for cooking food in a barbecue apparatus in accordance with the present application;

FIG. 7B illustrates a flowchart outlining one embodiment of a method for rapidly implementing a cold smoke barbecue mode for cooking food in a barbecue apparatus in accordance with the present application;

FIG. 8 illustrates a schematic diagram of an embodiment of a temperature control system of a barbecue apparatus according to the present application;

FIG. 9 illustrates a flow chart summarizing one embodiment of a method for quickly implementing a cold smoke barbecue mode for cooking food in a barbecue apparatus according to the present application;

FIG. 10 depicts a perspective view of an embodiment of a fire pot having a perforated floor and a landing zone according to the present application;

fig. 11 shows a top view of the fire pot shown in fig. 10 according to the present application.

Detailed Description

The present application relates generally to systems, methods, and apparatus for generating cold smoke in an oven, such as a barbecue smoke generator, and components and/or sub-components thereof. These components and/or sub-components enable a user to produce smoke at low temperatures for extended periods of time in a main oven or "cooking chamber" of the barbecue apparatus. For example, a user can generate smoke and various air temperatures in the cooking chamber of an oven in a closed loop environment at or below 150F for several hours at a time. Additionally or alternatively, the user can generate smoke and various air temperatures within the cooking chamber of the barbecue apparatus at or below 120°f, at or below 100°f, at or below 90°f, and/or at or below 80°f, as described in more detail herein.

In addition, the present invention may be employed to provide a device that allows a user to adjust or set various cooking modes, including changing temperatures over time, customizing the cooking modes and smoke temperatures in the barbecue apparatus described herein. The user can apply a motorized robot to achieve various initial smoke/cooking temperatures with a short warm-up time and also can change the smoke/cooking temperature quickly and accurately. Such extended periods of time, low temperature smoke processes (i.e., the "cold smoke barbecue mode") can provide ideal conditions for cooking and heating foods that can only be prepared with heavy smoke but require temperatures near ambient temperatures (e.g., smoked salmon, smoked cheese, etc.).

In general, wood combustion can be understood to be carried out in approximately several different stages, typically three to four different stages. For example, the united states fire protection association (NFPA) divides four phases of a fire into "ignition", "development", "full development" and "debulking". Meanwhile, the E3A organization (Exploring ENERGY EFFICIENCY AND ALTERNATIVES) describes the combustion of wood in three steps, namely, "moisture evaporation", "smoke formation" and "charcoal". Similar terms are used by others in the industry to describe these stages, such as "initial stage", "wood moisture stage", "creosote stage" and "heat stage". Still others categorize these stages into smaller subclasses, in part, as to how or when certain volatile components are released or burned.

Stages of wood combustion

For the purposes of the specification and claims, the wood combustion stage will be understood to fall into one of the following four categories, "moisture evaporation", "hydrocarbon evaporation", "gas vapor ignition/combustion" and "char combustion".

Stage 1-evaporation of water. In stage 1, as the temperature obtained by the wood increases, various volatile components in the wood begin to evaporate from the wood, including some water. After reaching the water boiling point, i.e., 212°f, most or all of the water in the wood evaporates, allowing the wood to dry sufficiently to fit for initial combustion. The moisture evaporation stage absorbs rather than generates heat. As the surface temperature of the wood increases beyond about 212°f to about 450°f and higher, the wood splits to release the main gases rich in the creosote, namely carbon dioxide, carbon monoxide, and acetic and formic acids. However, these gases do not ignite before the moisture evaporates and the temperature is not as high as the ignition temperature.

Stage 2-hydrocarbon vaporization. As the temperature increases, the chemical structure of the wood molecules begins to break apart by pyrolysis to produce components such as tar droplets and other combustible gases. In stage 2, heat is still predominantly absorbed rather than generated. However, the temperature of the combustible gas is not so high at this stage that it is capable of spontaneous combustion. A process in this range burns producing visible smoke.

Stage 3-gas vapor ignition and combustion. As wood fires at higher temperatures, typically at or above about 540°f, carbon reacts with oxygen to produce a combustible gas, such as carbon monoxide. If sufficient oxygen and heat are present, the carbon monoxide will react with the oxygen to form carbon dioxide. Complete combustion of wood produces almost exclusively 1) steam, 2) carbon dioxide, 3) heat, and 4) non-combustible ash. The less fully combusted, the more carbon monoxide, the combustible hydrocarbons and other gases will be left unburned. Thus, the complete combustion is generally 1100°f to 1225°f, even up to 2000°f, depending on the combustible gas being exposed to a sufficiently high temperature. Smoke generated in these temperature ranges tends to be less visible (invisible or "blue" smoke), and all or nearly all of the combustible material is now burned.

It will be appreciated that the combustion temperature required to achieve efficient combustion may vary based on the amount of oxygen present. For example, a smaller amount of oxygen requires a higher temperature to ignite the material, while a higher amount of oxygen enables combustion at a lower temperature.

Stage 4-coke combustion. From the 2019 american fire protection association (NFPA) nomenclature assembly, the term "coke" refers to the formation of brittle residues when a material is exposed to thermal energy. In this regard, coked wood includes brittle residue wood. Coked wood can burn further, but is typically required to be in direct contact with oxygen for combustion and occurs only after the initial stage is completed. Specifically, after the first three phases, the only remaining combustible material is char in the charcoal, which burns with little or no flame.

Continuous combustion versus smoldering

It is understood from NFPA, and as used herein, the term "combustion" refers to a chemical oxidation process that occurs at a rate fast enough to generate heat.

It is understood from NFPA, and as used herein, the term "ignition" or "pilot" refers to a condition in which sufficient heat is provided to trigger the first stage of combustion. Similarly, NFPA defines the term "self-ignition" as triggering combustion with heat, but without sparks or flames. For example, at a certain temperature (as compared to a certain level of oxygen), wood pellets no longer need to be ignited with an external heat source to burn, and simply self-burn in response to given environmental conditions.

In this regard, "combustion" may be understood and/or referred to in various ways, including an initial stage 1 or 2, in which sufficient heat causes decomposition of the fuel source (e.g., used interchangeably with "ignition"), up to stages 3 and 4, in which sufficient heat is present such that other chemical decomposition processes occur, such as concomitant oxidation, without further stimulation (e.g., "self-ignition"). This is also referred to herein as "continuous combustion" or "fire" (see NFPA2019 assembly).

The term "smoldering" as used herein is not self-sustaining or continuous without the need for an external heat source, as opposed to continuous combustion. Referring to the four stages listed above, smoldering typically occurs after stage 1 and at a point between stages 2 and 3. Charcoal cannot generate enough ambient heat to cause a durable ignition (or self-ignition) of surrounding wood particles that are not in direct contact with a heat source, and thus cannot be maintained to a point where the surrounding wood particles are consumed by continuous combustion or self-ignition.

Smoke by-product

As previously described, smoke contains various byproducts, such as soot, ash, and creosote. The definition provided in the 2019NFPA nomenclature compilation is that the term "ash" as used herein refers to solid residues that remain intact after combustion, and carbon particles generated in the term "soot" flame as used herein. Soot is a byproduct of incomplete combustion.

Creosotes (i.e., wood creosotes) are oily components produced from the combustion of wood, including a variety of phenol derivatives, including decomposed/pyrolyzed lignin, in the form of orthomethoxyphenol (C ₆H₄(OH)(OCH₃), and dimethoxyphenol (1, 3-Dimethoxy-2-hydroxybenzene). Among these components, dimethoxyphenol is understood to be a chemical that mainly produces the smoke aroma in barbecue, whereas orthomethoxyphenol is used to produce taste sensation. Lignin derivatives are the largest contributor to the desirable smoke taste and typically decompose during stage 3, i.e., at temperatures from about 540°f to about 1000°f, preferably from about 752°f to about 923°f.

In this regard, creosotes, particularly lignin derivatives, can positively enhance taste and color of smoked foods and can be used as preservatives. However, if the balance of chemicals in creosotes shifts towards an undesirable direction, the food taste may be bitter. For example, visible smoke produced at lower temperatures in efficient combustion contains a higher proportion of soot and ash and produces a more bitter taste in foods. The visible smoke produced at higher temperatures in stage 3 contains a lower proportion of ash and lignin decomposition products, and produces a more desirable taste and appearance in the food.

Cold cigarette

In view of the foregoing, the "cold smoke" applied in accordance with the present invention is smoldering fuel and simultaneously limits smoke generated when the fuel is continuously combusted. In particular, the cold smoke according to the present invention is created by intermittently applying specific environmental conditions to localized groups of wood particles in a cupping jar such that these specific wood particles achieve a suitable level of smoke by-product (i.e., early stage 3 level combustion) while effectively maintaining the remaining wood particles under stage 1 and stage 2 conditions. In this regard, the cold smoke requires repeated ignition of the fuel to maintain smoldering over a period of time, such as from about 5 minutes to about 1 hour, about 2 hours, about 3 hours, about 4 hours, or about 5 hours or more.

At least one reason for this is that the heat applied by the external heat source is low enough, or discontinuous or intermittent enough, that the ambient heat is too low to cause sustained self-ignition or combustion. In addition, as previously described, sufficient oxygen is provided to the wood pellets at the correct time, in combination with a low temperature intermittent heat source, so that smoke byproducts formed in stage 3 of combustion can be produced in the fire pot while still maintaining the low temperature in the main oven. Thus, the various embodiments of the oven described herein create desirable environmental conditions for intermittently igniting localized subsets of wood pellets, at least through control of the heat source and blower (oxygen source), while still maintaining a relatively low primary oven temperature level. In particular, various embodiments of the present invention optimize the production of lignin byproducts in the firebox while maintaining the relatively low temperatures of smoke and air in the cooking chamber.

For example, immediately prior to stage 3 or in an early stage of stage 3, or during the passage from stage 2 to stage 3, cold smoke resulting from smoldering fuel is achieved in such a way that lignin in the firebox is maintained at a temperature of less than or equal to about 150°f, preferably from about 120°f to about 150°f, less than or equal to about 120°f, preferably from about 100°f to about 120°f, less than about 100°f, preferably from about 90°f to about 100°f, less than about 90°f, preferably from about 80°f to about 90°f, less than about 80°f, preferably from about 70°f to about 80°f, and/or at a temperature up to about 70°f, respectively, in the main oven.

Thus, the term "cold smoke barbecue mode" as used herein typically refers to the features and settings of the main oven and the firebox of the barbecue apparatus being manipulated to produce the desired composition of smoke in the firebox while maintaining a low main oven temperature.

Cold smoke barbecue device and method

The various embodiments of the barbecue apparatus described herein can provide desirable smoke at a lower temperature (i.e., cold smoke), which can impart a pleasing taste and smell to food.

Turning now to the drawings, FIG. 1 shows a barbecue apparatus 100 including an upper food warming/cooking chamber 105 in which a user can prepare food. The barbecue apparatus 100 of fig. 1 also includes a lower portion disposed below the cooking chamber 105, which houses the screw feeder system and the firebox. The lower portion below the cooking chamber 105 may also include various other components, such as a blower and a heating element. These systems and other components housed in the lower portion below the cooking chamber 105 will be presented and described in more detail below with reference to fig. 2-5.

Still referring to fig. 1, the illustrated embodiment of the barbecue apparatus 100 further includes a hopper 115 and a user control interface 120. The user can open the top of the hopper 115 and introduce fuel, such as wood pellets, through the hopper 115 into the feeder system of the lower portion of the oven 100. The user can adjust the control knob, or various other control interface buttons, to adjust the temperature of the food warming/cooking chamber 105 of the grilling device 100. Again, FIGS. 6-8 and the following description focus more on the user control interface and temperature control features of the grilling device 100, particularly with respect to cold smoke and related methods.

It will be appreciated that the embodiment of the barbecue apparatus 100 shown in fig. 1 is an example of a barbecue apparatus according to the present application. One or more embodiments of the grilling device 100 can include other components. For example, in one or more embodiments, the user control interface 120 may include a display screen, multiple other buttons or knobs, and/or touch screen technology.

Furthermore, one or more embodiments of the barbecue apparatus 100 may include similar components that are disposed in different positions relative to one another without affecting the basic functionality of the barbecue apparatus 100. For example, one or more embodiments of the barbecue apparatus 100 can include a hopper 115 located on the right side of the barbecue apparatus 100 or a user control interface 120 located anywhere else on the barbecue apparatus 100.

In addition, for example, one or more embodiments of the grilling device 100 can include a DC power source, not shown in FIG. 1. In one or more embodiments of the barbecue apparatus 100, the direct current power source can include a lithium ion battery. One or more embodiments may include other dc power sources. For example, in one or more embodiments, the barbecue device 100 can include one or more alkaline batteries. The barbecue apparatus 100 may also include other dc power sources. Additionally or alternatively, the grilling device 100 can include one or more ac power sources and one or more rectifiers.

It is understood that the manufacturer may place the dc power source in various locations on the inside or outside of the barbecue device 100. The DC power source may power the various components of the grilling device 100, including, but not limited to, the screw feeder 205, the blower, the heating element, and the electronic display of the user control interface 120.

In this regard, FIG. 2 illustrates an embodiment of the screw feeder system 200 in the barbecue apparatus 100 of FIG. 1, which is powered by a power source, such as the DC power source described herein. The embodiment shown in FIG. 2 includes a screw feeder 205, a fire pot 210, a blower 215, a heating element 220, and one or more temperature sensors 240a-b. As shown, the motor 225 can engage the screw feeder 205 at one end to rotate the screw feeder 205. A fire pot 210 is positioned at the other end of the screw feeder 205 for receiving fuel pellets into the interior space 230 of the fire pot 210 through an opening 235 in the side of the fire pot 210.

In addition, fig. 2 shows that the heating element 220 is positioned at or near the interior space 230 of the fire pot 210. In addition, the manufacturer may place the blower 215 in or communicate with a lower portion of the barbecue apparatus 100 below the cooking chamber 105. In this manner, blower 215 is able to circulate air (specifically, oxygen) through the lower portion and over and/or around heating element 220. Air flowing over the heating element 220 can enter the interior space 230 of the fire pot 210 after flowing over the heating element 220 from above. In this manner, blower 215 can increase or decrease the combustion of fuel within fire pot 210 by providing or decreasing the available oxygen provided to fire pot 210. Blower 215 also drives convective heating as it blows oxygen past heating element 220 within interior space 230 of fire pot 210.

Additionally, as previously described, in addition to one or more temperature sensors in the main oven, the screw feeder system 200 may include one or more temperature sensors 240a-b disposed within or near the interior space 230 of the firebox 210, as discussed in more detail herein. One or more temperature sensors 240a-b shown in fig. 2 are configured to detect the temperature within the fire pot 210 as the fuel burns. It is to be appreciated that one or more embodiments may include more or fewer temperature sensors than the number of temperature sensors 240a-b shown in fig. 2. For example, in one or more embodiments, the screw feeder system 200 may include one temperature sensor, three temperature sensors, four temperature sensors, five temperature sensors, or more than five temperature sensors.

In addition, one or more embodiments of the screw feeder system 200 may include one or more temperature sensors 240a-b positioned at locations other than those illustrated, within the interior space 230 of the firebox 210 or proximate to the interior space 230. For example, in one or more embodiments, the fire pot 210 may include one or more temperature sensors 240 disposed on a sidewall of the interior space 230 of the fire pot 210, on a floor of the fire pot 210, or on both. In one or more embodiments, the manufacturer may position one or more sensors 240 directly above, directly below, or directly outside the interior space 230 of the fire pot 210.

It is to be appreciated that the manufacturer can place one or more temperature sensors 240 at any number of locations within the interior space 230 of the firebox 210 or proximate to the interior space 230 such that the temperature sensors 240 can detect the temperature within the interior space 230 of the firebox 210.

Fig. 3 illustrates an embodiment of a screw feeder system 300 in use. The embodiment of the screw feeder system 300 shown in fig. 3 is similar to the embodiment shown in fig. 2. In addition, fig. 3 shows a grilling surface 305 inside the cooking chamber 105, fuel 310 such as wood pellets, and a dc power supply 325. It is understood that various types of fuels 310 other than fuel pellets may be used.

Fig. 3 also shows two temperature sensors 242, which are disposed inside the cooking chamber 105. In at least one embodiment, the two temperature sensors 242 are configured to sense the temperature of smoke within the cooking chamber 105. The position of the temperature sensor 242 within the cooking chamber 105 may vary. For example, in at least one embodiment, the temperature sensor 242 is disposed at the side and middle of the cooking chamber 105.

Also, in at least one embodiment, the cooking chamber 105 includes more or fewer sensors than the two sensors 242 shown in fig. 3. For example, in at least one embodiment, the cooking chamber 105 includes only one sensor 242. In at least one embodiment, the cooking chamber 105 includes three or more sensors 242 disposed therein.

Furthermore, in at least one embodiment, the grilling device 100 includes only one temperature sensor 242 disposed in the cooking chamber 105, and no other temperature sensor (outside of the heat bar heating element 220). Additionally or alternatively, any of the temperature sensors 242, 240a, 240b described herein may be used alone in the barbecue apparatus 100, or in combination with one or more other temperature sensors 242, 240a, 240b located only in the cooking chamber 105, or located within or proximate to the firebox 210, or disposed in association with both the cooking chamber 105 and the firebox 210.

In the embodiment shown in fig. 3, a user can feed fuel 310 through hopper 115 into screw feeder 205. The motor 225 engages the screw feeder 205 and rotates the screw feeder 205. Rotating the screw feeder 205 causes a defined amount of fuel 310 to be fed into the interior space 230 of the firebox 210 for ignition. Ignition of the fuel 310 generates heat and smoke 315 that rises to heat and/or expose the grilling surface 305 to the smoke 315. Notably, to maintain cold smoke, pellet oven 100 directs the screw feeder to dispense only a small amount of pellets at a time so that the pellets can be at least partially combusted without generating sufficient heat within the main oven to exceed the cold smoke temperature, e.g., from about 70°f to about 150°f.

As shown, the blower 215 blows air 330 through the heating element 220, through an opening 335 in the fire can 210, and into the interior space 230 of the fire can 210 where the fuel 310 resides. In such embodiments, the dc power supply 325 provides electrical power to the heating element 220, thus heating the heating element 220 via resistive heating. The air 330 blown past the heating element 220 is then transferred to the fuel (pellets) 310 within the fire pot 210, causing convective heat transfer to the fire for ignition. Alternatively, heating element 220 is positioned in direct contact with the pellets to provide more direct heat. Once ignited, the fuel 310 smolders to generate heat and smoke 315, the smoke rises to warm/heat and expose the grilling surface 305 of the pellet oven 100 to the smoke 315.

Furthermore, in at least one embodiment, the firebox 210 includes perforations in the floor and/or side walls thereof. In such embodiments, air 330 circulated by blower 215 enters fire pot 210 through perforations to provide oxygen for combustion of fuel 310.

Additionally or alternatively, in one or more embodiments, the heating element 220 may extend into the interior space 230 of the firebox 210. In this manner, the heating element 220 is also capable of transferring heat to the fuel 310 by conduction heat transfer to the fuel 310 due to the direct contact between the heating element 220 and the fuel 310.

In this regard, fig. 4 and 5 depict various embodiments of heating elements disposed at, within, or near the interior space 230 of the fire pot 210. For example, fig. 4 depicts a cross-sectional view of an embodiment of a fire pot 210 with a heating element 220 extending therein. In one or more embodiments, the heating element 220 extends into the fire pot 210 to achieve direct contact with the fuel 310 residing in the interior space 230 of the fire pot 210, as shown in fig. 3 and as previously noted. In this embodiment, the heating element 220 is capable of igniting the fuel 310 in the interior space 230 of the cupping jar 210 by conduction of heat transfer fuel 310 and between the heating element 220.

Additionally or alternatively, the blower 215 can blow air 330 through the heating element 220 and into the interior space 230 of the fire can 210 through the opening 235 to ignite the fuel 310 by convective heat transfer. For example, fig. 5 illustrates an alternative embodiment of the heating element 220 and the fire pot 210 configured such that the heating element 220 is not in contact with the fuel 310.

In such embodiments, the heating element 220 does not extend into the interior space 230 of the fire pot 210. Thus, the heating element 220 does not ignite the fuel 310 in the fire pot 210 by direct contact. Instead, in this non-contact configuration, the blower 215 blows air 330 through the heating element 220 and into the interior space 230 of the fire pot 210 through the opening 235 so as to transfer the pilot fuel 310 by convection only.

In one or more embodiments, the heating element 220 may include a ceramic material and two or more electrical leads 505. In particular, the manufacturer can connect the DC power source 325 to the leads 505 of the heating element 220 and provide electrical power to the heating element 220. The power supply 325 delivers current through the heating element 220 and the resistance of the heating element 220 causes the ceramic material to raise temperature.

One advantage of ceramic materials is that the ceramic can change temperature at a faster rate than some other materials used in prior art heating elements. In addition, ceramic materials are durable and more resistant to corrosion than heating elements of other materials employed in the prior art, such as metals.

However, it is understood that in one or more embodiments of the application, the heating element 220 may comprise materials other than ceramic materials. For example, the heating element 220 may include a stainless steel heating element or a heating element constructed of other thermally conductive material. The heating element 220 may comprise a stainless steel heating element for igniting the fuel 310 in the fire pot 210 by conduction heat transfer as previously described. Further, the heating element may comprise a ceramic heating element for igniting the fuel 310 in the cupping jar 210 by conduction heat transfer, convection heat transfer, or both, as previously described.

With the components of the screw feeder system 200, the fire pot 210, and the heating element 220 described herein, a user can adjust the temperature of the smoke 315, which heats and/or surrounds the grilling surface 305 in at least three ways. First, a user can adjust the power supplied to the heating element 220 to raise or lower the temperature of the heating element 220. Second, the user can adjust the flow rate of the air flow provided by the blower 215, which flows through the heating element 220 and into the interior space 230 of the fire can 210. Third, the user can adjust the rate at which the screw feeder 205 feeds fuel 310 into the interior space 230 of the firebox 210.

Any of the three previous adjustment methods result in adjusting the speed and/or amount of fuel 310 ignited in the fire pot 210. The amount and rate at which fuel 310 is ignited and oxygen is provided results in the adjustment of the smoke temperature by controlling which combustion phase occurs. Too much or too hot pilot fuel 310, or too much oxygen to fuel 310, may result in the fuel 310 burning continuously in stage 3. Instead, intermittently igniting the fuel 310 within the fire tank 210, in combination with intermittently increasing and decreasing the amount of oxygen circulated by the blower 215 into the fire tank 210, may maintain smoldering of the fuel 310 in combustion stage 2. The three adjustment methods described above also affect the efficiency of smoke generation and the amount of smoke generated by burning fuel 310.

For example, a high temperature flame produced by continuous combustion of fuel 310 includes self-ignition in combustion stage 3 such that less smoke 315 is produced per dose of fuel 310. The smoke generated by such a high temperature flame will also have an elevated smoke temperature. Such high temperature smoke may often be undesirable in order to smoke food within the illustrated barbecue apparatus 100. However, a user may wish to use a high temperature smoke for popping certain foods.

Instead, the cold smoke produced by smoldering the fuel 310 prior to combustion stage 3 results in very efficient smoke production and preferred smoke taste delivery to the food. For example, cold smoke may be generated by smoldering based on intermittent pilot fuel sources and intermittent increases and decreases in oxygen supplied by blower 215 to subgroup fuel 310 within fire pot 210. This is to be distinguished from self-ignition, which may result in continuous combustion of a fuel source, such as a large high temperature flame. The cold smoke generated by the application according to the present invention can be generated in a larger volume than the fuel 310 per dose consumed by conventional high temperature smoke.

In at least one embodiment, the cold smoke generated by smoldering of the fuel prior to combustion stage 3 is less than 150°f. For example, in one or more embodiments, the cold smoke may be less than 120°f,100°f,90°f,80°f, or preferably less than 70°f.

It is therefore important for the screw feeder system 200, heating element 220, blower 215, and associated conditioning system, including the temperature control system described herein, to enable a user to quickly, accurately, and reliably produce a desired amount of smoke at a desired temperature over a predetermined period of time. For example, in one or more embodiments, the control system of the barbecue apparatus described herein can maintain smoldering of the fuel 310 within the firebox 210 for at least five minutes. In one or more other embodiments, smoldering combustion can be maintained for at least ten minutes, fifteen minutes, or twenty minutes. Furthermore, in some cases, the user may wish to change the temperature and amount of smoke produced over time.

For example, when cooking one type of food, the user may wish to first avoid producing a high temperature flame and a high temperature smoke, but then increase the temperature of the grilling surface 305 toward the end of the cooking time to pop the food. Alternatively, in preparing another type of food, the user may wish to first high temperature to pop the food, and then reduce the temperature of the smoke produced over time. These smoke temperature settings and adjustments over time are referred to herein as "barbecue modes". The various barbecue modes described herein may include constant smoke temperature, high or low temperature, and/or temperature that varies over time.

Fig. 6-9 illustrate various embodiments of temperature control systems and methods in which various grilling modes are quickly and accurately implemented using the components of the grilling device 100 described herein. The user can select or adjust the grilling mode of the grilling device 100 by entering instructions into the user control interface 120. In this regard, FIG. 6 depicts an embodiment of the user control interface 120 that includes a temperature adjustment knob 605 and a display 607. The display 607 may present information to the user such as, but not limited to, the set temperature of the oven, the actual temperature of the oven, the elapsed time, or any other information that aids the user in cooking food in the oven 100.

It will be appreciated that other applications of the user control interface 120 may include more than one display 607 or no display 607, as well as any number of buttons, knobs, switches, and the like, and combinations thereof, with which a user can adjust the temperature of the barbecue apparatus 100. The user interface 120 shown in fig. 6 is vegetation displayed as a presentation control system interface. One or more embodiments may include other configurations of the user interface 120. For example, one or more embodiments of the user control interface 120 may include a digital temperature indicator, touch screen buttons, and customer customizable, preset, and/or programmable grilling mode options.

According to the embodiment of the temperature control system 600 shown in fig. 6, once the user selects or sets the grilling mode using the control interface 120, the processor 610 directs the power source to supply power to the various components of the grilling device 100. For example, the processor 610 may increase the current supplied to the screw feeder 205, causing the screw feeder 205 to rotate faster and increasing the amount of fuel fed into the fire pot 210. Additionally or alternatively, the processor 610 may increase the power supplied to the blower 215 to increase the oxygen within the fire pot and thus increase the combustion rate of the fuel 310. In addition, the processor 610 can regulate the power supplied to the heating elements 220, either alone or in combination with the regulation of the supply to the screw feeder 205 and blower 215.

The processor receives the feedback information and adjusts the power output to the screw feeder 205, the heating element 220, and the blower 215 to maintain or adjust the smoke temperature specified by the selected grilling mode. In one or more embodiments, the temperature sensor 240 provides this feedback information to the processor 610. For example, as the fuel 310 burns in the interior space 230 of the fire pot 210, the temperature sensor 240 sends temperature information back to the processor 610.

For example, if the temperature is too high, the processor can reduce the power output to the heating element 220 to slow down the ignition, reduce the power output to the blower 215 to attenuate combustion, and/or reduce the power output to the screw feeder 205 to slow down the rate of fuel 310 feed into the fire pot 210.

Additionally or alternatively, in at least one embodiment, the processor can increase the power output to the screw feeder 205 to increase the rate at which fuel 310 is fed into the fire pot 210. In such an embodiment, adding enough additional fuel 310, such as wood pellets, to other wood pellets that have been burned in the cupping jar 210 will choke the combustion of the fuel 310. This choking will reduce the amount of oxygen supplied to the combustion fuel 310 so that the fuel 310 does not enter combustion stage 3.

Conversely, if the temperature is too low, the processor can increase the power output to the heating element 220 to accelerate ignition, increase the power output to the blower 215 to increase combustion, and/or increase the power output to the screw feeder 205 to increase the rate at which fuel 310 is fed into the fire pot 210. Increasing the rate at which fuel 310 is fed into the fire pot 210 can increase combustion and temperature by providing more fuel 310, so long as the choking previously described is not caused by adding too much fuel 310.

In this manner, based on feedback information provided by the sensor 40, the temperature control system 600 maintains the desired environmental conditions within the firebox 210 to achieve the cold smoke generated between the combustion stages 2 and 3, as previously described. That is, controlling the heating element 220, blower 215, and screw feeder 205 in combination, based on information fed back from sensor 240, causes a sub-set of fuel 310, such as wood pellets, within the fire pot 210 to smolder while avoiding self-ignition of the sub-set of fuel 310.

In this way, the processor and feedback information from the one or more temperature sensors 240 can cooperate to form part of a control system feedback loop based on basic proportional, integral, and derivative control system principles. Thus, the embodiment of the temperature control system 600 shown in fig. 6 enables a user to quickly and accurately achieve, maintain, and adjust the temperature of the smoke within the barbecue apparatus 100.

In this regard, as previously described, one or more temperature sensors 240 as described herein are disposed within or near the interior space 230 of the fire pot 210. With the temperature sensor 240 so positioned, the feedback temperature provided to the processor 610 includes the fire pot temperature information detected within the interior space 230 of the fire pot 210. It will be appreciated that the type of feedback information provided by the one or more temperature sensors 240 to the processor 610 depends on the location of the one or more temperature sensors 240.

For example, in one or more embodiments, the barbecue apparatus 100 can include one or more temperature sensors 240 disposed outside of the interior space 230 of the firebox 210. For example, in one or more embodiments, the grilling device 100 can include one or more temperature sensors 240 positioned above the fire pot 210, above the grilling surface 305, and/or above food prepared on the grilling surface 305 within the warming/cooking chamber 105. For example, in embodiments in which one or more temperature sensors 240 are disposed within the warming/cooking chamber 105, the feedback information sent back to the processor 610 will include smoke temperature information from smoke within the warming/cooking chamber 105 of the barbecue device 100.

In general, a temperature control system based only on feedback information from the temperature sensor 240 disposed in the heating/cooking chamber 105 has a long warm-up time. This is because at the time the warming/cooking chamber 105 smoke reaches the desired temperature and this information is sent back to the processor 610, the fuel 310 burned within the firebox 210 may be self-sustaining and may have risen to an undesirable flame before the processor 610 can reduce the power supplied to the heating element 220 or various other components. As a result, the high temperature flame will continue to raise the temperature of the warming/cooking chamber 105 until the fuel 310 is further consumed due to the continuous combustion in combustion stage 3, even though the heating element 220, blower 215, and spiral feeder 205 have been suspended or slowed.

The lag time between the combustion of the fuel 310 and the temperature of the smoke in the warming/cooking chamber 105 results in increased warm-up time. For example, even if the processor 610 completely stops the screw feeder 205 from feeding fuel 310 into the fire pot 210, the existing fuel may require time to burn off to achieve smoldering and the desired amount of smoke and lower temperature level is achieved by the control system 600.

To reduce the preheating time as described above, one or more temperature sensors 240 are positioned at or near the interior space 230 of the firebox 210. In this way, the temperature sensor 240 provides feedback information to the processor regarding the temperature within the cupping jar 210, rather than just the temperature of the smoke within the warming/cooking chamber 105. In this regard, if the flame is created by a self-sustaining uncontrolled combustion of the fuel 310 within the interior space 230 of the fire pot 210, the temperature sensor 240 therein can send this information back to the processor 610 before the combustion becomes continuous.

Thus, in at least one embodiment having one or more temperature sensors 240 located within, at, or near the interior space 230 of the firebox 210, the processor 610 does not need to wait until the smoke within the warming/cooking chamber 105 reaches the desired temperature to regulate the power output to the screw feeder 205 and other components of the barbecue apparatus 100. Instead, the flame can be detected as it forms in the fire pot 210, and the processor can prevent uncontrolled combustion by reducing the electrical power output to the heating element 220, blower 215, augers 205, or other components.

The increased reaction time of the temperature control system 600 due to the placement of one or more temperature sensors 240 within or near the interior space 230 of the firebox 210 reduces overshoot of the desired smoke temperature specified by the barbecue mode. Reducing or even avoiding overshoot of the smoke temperature within the barbecue apparatus 100 eliminates the need to wait for the fuel to burn out in order to readjust to the desired smoke temperature. Thus, by one or more temperature sensors 240 disposed at, near, or within the interior space 230 of the firebox 210, the warm-up time may be reduced.

This reduced warm-up time is particularly advantageous when the user-selected grilling mode includes a cold smoke grilling mode. As previously mentioned, the term "cold smoke" as used herein refers to smoke produced by smoldering of fuel 310, such as by intermittently igniting a fuel source in order to avoid self-sustaining combustion. In particular, the term "smoldering" as used herein refers to burning fuel 310 without producing a flame. Charcoal can be considered to burn inefficiently, producing large amounts of smoke, or more efficiently. The smoke generated by smoldering the fuel 310 is substantially lower in temperature than the smoke generated from the high temperature flame. The cooler smoke generally provides a preferred mouthfeel and delivers a more pleasing taste to the food being prepared in the warming/cooking chamber 105.

For example, in one or more embodiments, the cold smoke generated by smoldering the fuel prior to combustion stage 3 is less than 150°f. In one or more other embodiments, the cold smoke may be below 120°f,100°f,90°f,80°f, or preferably below 70°f.

In order to quickly generate cold smoke due to smoldering, it is necessary to avoid/eliminate flames formed by continuous combustion and self-ignition of the fuel 310. As previously described, the various embodiments of the control system 600 and temperature sensor 240 configurations described herein can reduce the preheating time required to generate smoldering combustion and avoid high temperature flames within the interior space 230 of the firebox 210.

Accordingly, various embodiments of the temperature control system 600, in combination with various components of the barbecue apparatus 100, including one or more temperature sensors 240 disposed within, at, or near the interior space 230 of the firebox 210, can achieve cold smoke generated by smoldering fuel in less than 10 minutes. In one or more embodiments, the preheat time for the cold smoke barbecue mode may be less than 9 minutes, less than 8 minutes, or less than 7 minutes. In one or more embodiments, the preheat time for the cold smoke barbecue mode may be less than 6 minutes, less than 5 minutes, and preferably less than 4 minutes.

To further clarify the temperature control system 600 shown in fig. 6, fig. 7A shows a flowchart of a method 700a of controlling the smoke temperature of the grilling device 100 using the temperature control system 600 according to fig. 6. A first step 705a may include activating a heating element. For example, the heating element 220 is illustrated in fig. 2-5.

A second step 710a of method 700a may include feeding fuel into the fire pot and providing oxygen to the fuel to ignite the fuel with the heating element activated. For example, this step is depicted in FIG. 3 and described above.

A third step 715a may include activating a blower to supply oxygen to the fuel within the fire canister and continuously supplying fuel to the fire canister at a first rate. A fourth step 720a may include measuring temperatures within the firebox and within the cooking chamber. This fourth step is illustrated by the sensors 240, 242 shown in fig. 3.

A fifth step 725a may include communicating the measured temperature to a processor. A sixth step 730a may include feeding fuel into the fire pot at a second rate based on the measured temperature. Additionally or alternatively, at least one embodiment of method 700a includes adjusting the power supplied to the heating element and/or blower to control the speed of ignition and combustion based on the measured temperature within the firebox and cooking chamber.

For example, to ignite the fuel 310 within the fire pot 210, as shown in fig. 3, the heating element 220 may be heated to 700 degrees or higher. At such temperatures, the fuel 310 contacting the heating element 220 is ignited and burned, and may even become coke in combustion stage 3 as previously described. However, by reducing the rate at which fuel 310 is fed into the fire pot 210, as previously described, the amount of individual fuel pellets per combustion may be limited.

For example, in at least one embodiment, once the heating element 220 is activated, the rotation of the screw feeder 205 may be slowed to provide only one, two, or three pellets at a time within the fire pot 210. In at least one embodiment, more than three pellets, including four pellets, or between five and ten pellets, are provided for combustion within the firebox 210 at any single time. A small amount of fuel 310 within the firebox burns to generate smoke, as described herein, but is insufficient to cause the temperature in the cooking chamber 105 to rise above the cold smoke temperature described herein.

Conversely, as previously described, the rotation of the screw feeder 205 may also be enhanced to supply sufficient fuel 310 into the fire pot 210 to choke the fuel 310 that has burned therein.

In one or more embodiments of the method 700a shown in fig. 7A, the temperature information obtained from the heating element includes the temperature within the interior space 230 of the firebox 210. Additionally, as previously described, one or more embodiments of the method 700a further include measuring temperature information, such as smoke temperature information obtained from the cooking/warming chamber 105. Accordingly, in such an embodiment, the adjustment of the power output to the heating element and blower, or the adjustment of the second speed at which fuel is supplied into the cupping jar in the sixth step 730a, may also be based on the smoke temperature within the cooking chamber 105.

For example, as discussed previously, temperature feedback information obtained from within the interior space of the firebox 210 may minimize control system overshoot and reduce warm-up time. However, any control system is prone to some degree of overshoot, even in small amounts. Additional data may be provided to the control system by obtaining feedback information from various additional sources, such as from within the cooking/warming chamber 105. Such additional information can improve the reaction time of the control system, which can result in a faster adjustment of the second rate at which power or fuel is supplied to the heating element 220, blower 215, or into the fire pot 210.

For example, if the temperature information obtained from within the fire pot 210 indicates that the flame is too hot, the control system will cease the power to the heating element 220, the blower 215, and/or reduce the second rate at which fuel is supplied into the fire pot 210. However, based on such a single information source reducing flame, the smoke temperature in the cooking/warming chamber 105 may be caused to drop below a desired level before the blower 215 increases the air circulation or the fuel second speed is again adjusted to raise the temperature in the firebox back to the desired level.

However, if the temperature of smoke from within the cooking/warming chamber reaches a desired temperature before the temperature of the heating element 220, the amount of air circulated by the blower 215, or the second speed at which fuel is supplied into the cupping jar 210 drops too low, these amounts may be raised based on the smoke temperature information within the cooking/warming chamber 105. In this way, the control system can react to both the smoke temperature and the cupping jar temperature and mitigate overshoot, thereby reducing the warm-up time. This also enables the system to maintain smoldering of the fuel 310 within the fire pot 210 by eliminating overshoot into the third combustion stage, thus avoiding combustion.

Additionally or alternatively, the smoke temperature obtained from within the cooking/warming chamber 105 may be revealed to the user. Thus, this information can also be used to inform the user of the actual temperature within the cooking/warming chamber 105 of the barbecue apparatus 100.

Further, in one or more embodiments, the method 700 may include, after the temperature information is sent to the processor, regulating the electrical energy input to the blower and/or heating element as previously described. In such embodiments, the processor can adjust the electrical energy input to the blower and/or heating element to adjust the smoke temperature and reduce flame from burning, as previously described. Furthermore, in such embodiments, the electrical power provided to the blower and/or heating element may be performed independently or in combination with each other. Further, such adjustment of the power supplied to the blower and/or heating element may be performed along with, or separately from, step 730a of supplying fuel into the fire pot at the second speed.

In this regard, fig. 7B shows a flowchart of a method 700B of controlling the smoke temperature of the grilling device 100 using the temperature control system 600 according to fig. 6. In at least one embodiment, the first step 705b of method 700b includes activating a heating element. The heating element 220 is depicted, for example, in fig. 2-5.

In at least one embodiment, the method 700b includes a second step 710b of feeding fuel into the fire pot for ignition. This step is illustrated, for example, in fig. 3.

In at least one embodiment of method 700b, a third step 715b includes activating the heating element and blower to ignite and burn the fuel within the firebox. The blower and heating element activated in this step 715b is depicted in fig. 2-5.

In at least one embodiment of method 700b, a fourth step 720b includes measuring the temperature within the firebox and cooking chamber. The temperature inside the fire pot may be measured by sensors 240, 240a, 240b disposed inside the fire pot, as shown in fig. 2 and 3. The smoke temperature in the cooking chamber 105 may be measured by a temperature sensor 242 in the cooking chamber 105, as shown in fig. 3.

In at least one embodiment, a fifth step 725b of the method 700b includes communicating the measured temperature to a processor. Such a processor is depicted in fig. 6 and described above.

In at least one embodiment of method 700b, a sixth step 730b includes adjusting the amount of electrical energy provided to the heating element and blower based on the measured temperature within the firebox and cooking chamber. The power supply 325 shown in fig. 3 is wired to the blower 215 and the heating element 220. In at least one embodiment, the processor depicted in FIG. 6 regulates the power output of the power supply 325 to the various components.

As indicated by step 730B in fig. 7B, cold smoke is maximized by adjusting the power supplied to blower 215 and heating element 220 while minimizing the temperature in cooking chamber 105, as described herein. For example, blower 215 and heating element 220 are adjusted to increase the temperature at which lignin is broken down into fuel pellets 310 while avoiding continuous combustion due to the self-ignition of surrounding fuel pellets 310.

In addition, in at least one embodiment of the methods 700a, 700B described herein, cold smoke is maximized while the temperature in the cooking chamber 105 is minimized by the adjustment of the rate at which fuel 310 is delivered into the firebox 210, as depicted in method 700a of FIG. 7A, in combination with the adjustment of the energy provided to the heating element 220 and blower 215, as depicted in method 700B of FIG. 7B.

Fig. 8 also illustrates an embodiment of a temperature control system 800. In the embodiment shown in fig. 8, temperature control system 800 includes user control interface 120, processor 610, power supply 325, heating element 220, auger 205, and blower 215. It is noted that the temperature control system 800 shown in fig. 8 does not include the sensors provided in the temperature control system 600 shown in fig. 6.

In contrast, in one or more embodiments, such as shown in fig. 8, the heating element 220 of the temperature control system 800 can function as a temperature sensor. For example, in one or more embodiments, the processor 610 can reduce the current provided from the power supply 325 to the heating element 220. Such a reduction in the current supplied to the heating element 220 may turn the heating element off so that it no longer ignites the fuel 310 combusted within the interior space 230 of the cupping jar 210.

Conversely, when the processor 610 reduces the power supplied to the heating element 220, the heat generated by the combustion of the fuel within the interior space 230 of the fire pot 210 affects the resistance of the heating element 220. The resistance of the heating element 220 is a function of the temperature of the heating element 220 itself.

Thus, a change in temperature within the interior space 230 of the firebox 210 will thus change the resistance of the heating element 220. These principles are the same as those of a resistance temperature detector called "RTD" when it operates. The resistance of the heating element 220 may be measured and sent back to the processor 610. In one or more embodiments, for example, an ohmmeter may be used to measure the resistance of the heating element 220.

Next, the processor 610 can convert/calculate the temperature within the cupping jar 210 based on the measured resistance between the current supplied to the heating element 220 and the electrical leads of the heating element 220.

Depending on the configuration of the heating element 220, various configurations may be used to use the heating element 220 as a heat sensor. For example, in one or more embodiments, as the temperature of the heating element 220 increases, the resistance of the heating devices in the heating element 220 also increases. In these embodiments, a resistive sensor, such as an ohmmeter (not shown), may be used to measure the resistance of the heating element 220. Such resistance measurements may be directly converted to temperature by the processor 610.

In general, the temperature of the heating element 220 typically corresponds to the resistance of the heating element 220. By calculating using the resistance as a factor, the temperature can be determined. Alternatively or additionally, one or more embodiments may include a look-up table provided in the processor 610 that correlates the resistance of the heating element 220 to temperature.

Further, in one or more embodiments, the heating element 220 may include a thermocouple. The thermocouple can generate a small voltage that can be sent back to the processor 610. The voltage may be used to determine the temperature of the heating element 220. It should be noted that in such an embodiment, an electrical current may be applied to the heating element 220 to heat the heating element 220 while the temperature is measured by the thermocouple.

In one or more embodiments, the current flowing through the heating element 220 and the voltage across the electrical leads of the heating element 220 may be measured while the heating element 220 is being activated to ignite the fuel 310 within the fire pot 210. Knowing the voltage and current supplied by the power supply 325 to the heating element 220 enables the processor 610 to determine the resistance of the heating element 220. As previously described, the resistance of the heating element 220 may be related to the temperature of the heating element, which may be related to the temperature of the fire pot 210.

Thus, as shown in fig. 8, one or more embodiments of the temperature control system 800 can use the heating element 220 itself as a temperature sensor to reduce the warm-up time of the barbecue apparatus 100 and precisely maintain smoldering of the fuel 310 to produce cold smoke for an extended period of time, as previously described. In such embodiments, other separate temperature sensors 240 may not be included. However, in one or more embodiments where the heating element 220 is also used as a temperature sensor, one or more other temperature sensors 240 positioned inside and/or outside the interior space 230 of the firebox 210 may also be included. For example, one or more other temperature sensors 240 may be disposed above the grilling surface 305 and/or within the warming/cooking chamber 105 of the grilling device 100.

In such embodiments, the processor 610 can adjust the power input to the various components of the barbecue apparatus 100 based at least in part on temperature information from both the heating element 220 and the one or more other temperature sensors 240.

To further clarify the temperature control system 800 shown in fig. 8, fig. 9 shows a flow chart of a method 900 of controlling the smoke temperature of the grilling device 100 using the temperature control system 800 according to fig. 8. A first step 905 of method 900 may include activating the heating element by providing a first amount of electrical energy to the heating element. A second step 910 may include feeding fuel into the fire pot to ignite the fuel with the heating element activated.

Next, a third step 915 may include continuously supplying fuel to the fire pot at a first rate. A fourth step 920 may include turning off the heating element by providing a second amount of electrical energy to the heating element. In one or more embodiments, the second amount of electrical energy is less than the first amount of electrical energy supplied in the first step 905. A fifth step 925 may include measuring the resistance of the heating element. A sixth step 930 may include converting the resistance measurement into temperature information.

Finally, a seventh step 935 may include supplying fuel to the firebox at a second speed, adjusting the electrical power output to the heating element 220, and/or adjusting the electrical power output to the blower 215 based on the temperature information to maintain the generation of cold smoke for an extended period of time. The extended period of time may be greater than 5 minutes, 10 minutes, 15 minutes, or preferably greater than 20 minutes.

In one or more embodiments of the method 900 shown in fig. 9, the temperature information obtained from the heating element includes the temperature within the interior space 230 of the firepot 210. Additionally, one or more embodiments of the method 900 may further include measuring temperature information, such as smoke temperature information from the cooking/warming chamber 105. Thus, in such an embodiment, in an eighth step 935, the second speed at which fuel is supplied to the fire canister or the electrical energy control of the heating element can also be based on the smoke temperature information.

Further, in one or more embodiments, the method 900 can include, after the temperature information is measured, adjusting the electrical energy input to the blower and/or the heating element, as previously described. In such embodiments, the processor can adjust the electrical energy input to the blower and/or heating element to adjust the smoke temperature and avoid burning of the fuel in the third combustion stage, as previously described. Furthermore, in such embodiments, the electrical power provided to the blower and/or heating element may be performed independently or in combination with one another. Further, such adjustment of the power supplied to the blower and/or heating element may be performed in conjunction with step 935 of supplying fuel to the firebox at a second rate, or independently.

Accordingly, the various embodiments of the temperature control system 800 and method 900, and the various components of the barbecue apparatus 100, including the heating element 220 used as a temperature sensor, described in fig. 8 and 9, respectively, enable cold smoke to be generated by smoldering of fuel in less than 10 minutes. In one or more embodiments, the preheat time for such a cold smoke barbecue mode may be less than 9 minutes, less than 8 minutes, or less than 7 minutes. In one or more embodiments, the preheat time for such a cold smoke barbecue mode may be less than 6 minutes, less than 5 minutes, and preferably less than 4 minutes.

Further, any of the temperature control system and component embodiments described herein can accurately achieve any number of grilling modes selected by a user. Such a barbecue mode may include a cold smoke barbecue mode, as previously described. Other barbecue modes may include a high temperature smoke barbecue mode, which is produced from a flame produced from the combustion of fuel in the third combustion stage. Still other barbecue modes may include a variety of different smoke temperatures and transitions between smoke temperatures over time.

For example, in one or more embodiments, the barbecue mode may include an initial cold smoke temperature that transitions over time to a high smoke temperature and vice versa. The temperature control systems and components described herein enable rapid and accurate implementation and maintenance of various smoke temperatures selected by a user. In addition, the temperature control systems and components described herein may enable transitions between multiple temperatures in a certain grilling mode at a set rate and for a set period of time, as specified by the user-selected grilling mode.

In addition to the foregoing, one or more applications of the barbecue apparatus 100 described herein can include additional features to improve ignition efficiency and/or reduce warm-up time in the firebox. For example, one or more embodiments of the barbecue apparatus described herein can include a firebox having perforations and/or a landing zone. For purposes of example, fig. 10 shows a perspective view of an embodiment of a fire pot 1000.

In the embodiment shown in fig. 10, the fire pot 1000 includes a plurality of holes 1005 in a base plate 1010. In this regard, fig. 11 depicts a top view of the fire pot 1000 shown in fig. 10, and more clearly shows the holes 1005 in the floor 1010 of the fire pot 1000. The plurality of holes 1005 in the base plate 1010 form a perforated base plate 1015.

Regarding the perforated floor 1015, the number, size, and distribution pattern of the holes 1005 in the perforated floor 1015 may vary. For example, in one or more embodiments, the perforated floor 1015 may include holes 1005 having a diameter of 1/32 inch or 1/16 inch. In one or more embodiments, the aperture 1005 may be 1/8 inch. In yet another embodiment, the manufacturer may provide a 1/4 inch diameter hole 1005. In yet another embodiment, the diameter of the holes may be greater than or equal to 1/3 or 1/2 inch. One or more embodiments may include a wide variety of different size and shape holes 1005 throughout the perforated base plate 1015.

Furthermore, the manufacturer may not randomly distribute the holes in a particular order, or schedule a small number or number of holes into a particular distribution pattern designed to optimize the ventilation of the fire pot 1000. In various embodiments of the fire pot 1000 having perforated floor 1015, holes 1005 allow air to enter the fire pot 1000 to facilitate fuel ignition and combustion. The holes 1005 also allow ash to fall through the perforated floor 1015 of the cupping jar 1000, resulting in a clean cupping jar 1000 that is substantially free of ash, soot, and creosote.

While the bottom vents 1005 can facilitate venting and reduce ash, soot, and creosote, they can also result in a reduced structural rigidity of the perforated floor 1015 if too much material is removed. Thus, the number and size of the holes 1005 may vary between embodiments, so long as the holes 1005 provide adequate venting capability to the fire pot 1000 without detrimentally reducing the structural rigidity of the perforated floor 1015. Additionally or alternatively, the manufacturer may include a vent 1005 located in a side wall 1020 of the fire pot 1000.

The embodiment of the fire pot 1000 shown in fig. 10 and 11 also includes a parking zone 1025. The parking zone 1025 includes a portion of the perforated floor 1015 closest to the heating element opening 335 that is devoid of apertures 1005. Because the apertures 1005 of the perforated floor 1015 allow air to pass through the floor 1010 of the fire pot 1000, the fuel 310 within the fire pot 1000 may move around, circulate, or otherwise be dispersed within the fire pot 1000.

In this regard, the parking zone 1025 provides an area on the perforated floor 1015 where fuel 310 can collect near the heating element 220 without being dispersed from the circulating air. In this manner, the parking zone 1025 may facilitate rapid and efficient ignition of the fuel 310 within the cupping jar 210.

Additionally or alternatively, the parking zone 1025 described above may also include a raised perimeter 1030 that at least partially surrounds the parking zone 1025. In one or more embodiments, the raised perimeter 1030 can include one or more walls of material that rise from the floor 1010 of the fire pot 1000. In one or more embodiments, raised perimeter 1030 at least partially surrounds parking area 1025 between parking area 1025 and aperture 1005 in the remainder of base plate 1010.

Thus, the raised perimeter 1030 surrounding the parking zone 1025 can provide a barrier to cause the fuel 310 to bunch (or "cluster") together on the parking zone 1025. The raised perimeter 1030 thus ensures that proper ignition of the fuel 310 occurs before air circulated from the blower 215 causes the fuel 310 to blow off of the landing zone 1025.

In one or more embodiments, raised perimeter 1030 of parking zone 1025 may include a single wall that extends completely around parking zone 1025 between parking zone 1025 and aperture 1005. In one or more embodiments, the raised perimeter 1030 may include two or more separate raised wall segments. The manufacturer may place the segments around the perimeter of the parking zone 1025 in a position that most effectively prevents the fuel 310 from being blown off of the parking zone 1025.

In such embodiments, the individual raised wall segments may have the same height or various heights. Furthermore, in various embodiments described herein, the height of the raised perimeter 1030 may vary. For example, in one embodiment, the height of the raised perimeter 1030 may be about 0.5 inches. In one embodiment, the height of the raised perimeter 1030 may be about 0.25 to 0.75 inches. In another embodiment, the height may be about 1 inch or 2 inches. In still other embodiments, the height of the raised perimeter 1030 may be less than about 0.25 inches or greater than about 2 inches.

In one or more embodiments, the manufacturer may use a mesh material to form at least the floor 1010 and/or the side walls 1020 of the fire pot 1000, rather than a solid material in which the vent holes are formed. The mesh material may be configured to allow the blower 215 to circulate air within the cupping jar 1000 and to allow ash, soot, and creosote to fall through the floor 1010 of the cupping jar 1000.

Test results, example 1

TABLE 1

As shown in table 1 above, 12 steps are performed in sequence, each step having specific conditions including screw feeder speed, power supplied to the heating element, and blower settings. The conditions of each step create different conditions in the barbecue apparatus, the temperature within the firebox, the specific combustion stage, and the cooking chamber temperature. As can be seen from the data of table 1, the fuel pellets can be intermittently added to produce smoke without raising the temperature of the cooking chamber.

Throughout the test, as pellets are added to increase burning or choking the existing fuel, the temperature of the firebox rises and falls, but the temperature in the cooking chamber remains constantly low until event 12, where self-ignition of the pellets creates a flame that increases the temperature of the cooking chamber. In this way, the cold smoke described herein is generated at a low temperature in the cooking chamber. Once the pellets ignite to produce a flame, the fuel may be choked, or other means of electrical power reduction, such as a blower, screw feeder, or heating element, to reduce the temperature and begin the entire cycle from event 1 to continue to produce cold smoke at low cooking chamber temperatures.

The foregoing test results shown in table 1 demonstrate one possible procedure for smoke formation and the corresponding smoke conditions. It may be noted that the stages (i.e., stages 1-4 described herein) may alternate as fuel pellets fall from the screw feeder 205 into the fire pot 210. It will be appreciated that various settings of the previous test results (e.g., blower speed, screw feeder speed) may be adjusted to extinguish the fire pot 210, or to increase the combustion efficiency of the fuel 310 in order to maximize lignin decomposition (e.g., events 9-10) while maintaining relatively low air and smoke temperatures within the cooking chamber 105.

Furthermore, the method may be practiced by a computer system comprising one or more processors and a computer readable medium such as a computer memory. In particular, the computer memory may store computer-executable instructions that, when executed by one or more processors, cause performance of various functions, such as the acts recited in the embodiments.

Computing system functionality may be enhanced by the ability of the computing system to interconnect to other computing systems via network connections. The network connection may include, but is not limited to, a connection via wired or wireless ethernet, a cellular connection, or even a computer-to-computer connection through serial, parallel, USB, or other connection. These connections allow the computing system to access services at other computing systems and receive application data from other computing systems quickly and efficiently.

Many computers are intended to be used through direct user interaction with the computer. Thus, the computer has input hardware and software user interfaces to facilitate user interaction. For example, modern general purpose computers may include keyboards, mice, touchpads, cameras, etc. for allowing users to enter data into the computer. In addition, various software user interfaces may be used.

Examples of software user interfaces include graphical user interfaces, text command line based user interfaces, function keys or hotkey user interfaces, and the like.

The disclosed embodiments may include or utilize a special purpose or general-purpose computer including computer hardware, as discussed in greater detail below. The disclosed embodiments also include physical and other computer-readable media for carrying or storing computer-executable instructions and/or data structures. Such computer-readable media can be any available media that can be accessed by a general purpose or special purpose computer system. The computer-readable medium storing the computer-executable instructions is a physical storage medium. The computer-readable medium carrying computer-executable instructions is a transmission medium. Thus, by way of example, and not limitation, embodiments of the invention may comprise at least two distinct computer-readable media, a physical computer-readable storage medium and a transmission computer-readable medium.

The physical computer readable storage medium includes RAM, ROM, EEPROM, CD-ROM or other optical disk storage (such as CD, DVD, etc.), magnetic disk storage or other magnetic storage devices, or may be any other medium that is used to store desired program code means in the form of computer-executable instructions or data structures and that can be accessed by a general purpose or special purpose computer.

Furthermore, upon reaching various computer system components, program code means in the form of computer-executable instructions or data structures can be automatically transferred from a transmission computer readable medium to a physical computer readable storage medium (or vice versa). For example, computer-executable instructions or data structures received via a network or data link may be buffered in RAM within a network interface module (e.g., a "NIC") and then ultimately transferred to computer system RAM and/or less volatile computer-readable physical storage media at a computer system. Thus, a computer readable physical storage medium may be included in a computer system component that also (or even primarily) utilizes transmission media.

Computer-executable instructions comprise, for example, instructions and data which cause a general purpose computer, special purpose computer, or special purpose processing device to perform a certain function or group of functions. The computer-executable instructions may be, for example, binary files, intermediate format instructions such as assembly language, or even source code. Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the features or acts described above. Rather, the described features and acts are disclosed as example forms of implementing the claims.

Those skilled in the art will appreciate that the invention may be practiced in network computing environments with many types of computer system configurations, including personal computers, desktop computers, notebook computers, message processors, hand-held devices, multiprocessor systems, microprocessor-based or programmable consumer electronics, network PCs, minicomputers, framework computers, mobile telephones, PDAs, pagers, routers, switches, and the like. The invention may also be practiced in distributed system environments where local and remote computer systems, which are linked (either by hardwired data links, wireless data links, or by a combination of hardwired and wireless data links) through a network, both perform tasks. In a distributed system environment, program modules may be located in both local and remote memory storage devices.

Alternatively or additionally, the functions described herein may be performed, at least in part, by one or more hardware logic components. For example, but not limited to, illustrative types of hardware logic that may be used include Field Programmable Gate Arrays (FPGAs), application Specific Integrated Circuits (ASICs), program specific standard products (ASSPs), system-on-chips (SOCs), complex Programmable Logic Devices (CPLDs), and the like.

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.

Claims

1. A grilling device includes a main oven having a cooking chamber for cooking food, a screw feeder system integrated with the main oven and configured to deliver wood fuel, a fire pot connected to the screw feeder system, the fire pot having an interior space configured to receive wood fuel dispensed by the screw feeder system, a heating element powered by a power source configured to provide heat to the interior space of the fire pot, a blower powered by the power source configured to provide oxygen to the interior space of the fire pot, and a first temperature sensor disposed proximate the fire pot, a second temperature sensor disposed proximate the cooking chamber, and a digital controller, wherein the grilling device is configured in association with the digital controller, the first temperature sensor, the second temperature sensor, the heating element, and the digital controller, wherein the digital controller is configured to intermittently ignite the wood fuel by the heating element and the blower in association with intermittently increasing and decreasing an amount of oxygen circulated to the fire pot to maintain smoldering fuel in the fire pot such that no smoke is generated by the wood fuel outside of the fire pot at least about 150 DEG F, while maintaining smoldering of the wood fuel at least about a low temperature of about 150 DEG F.

2. The barbecue apparatus of claim 1, further comprising a third temperature sensor positioned adjacent one of the firebox or the cooking chamber.

3. The grilling device as recited in claim 1, wherein the grilling device is configured to measure a characteristic of the heating element to determine the temperature.

4. The grilling device of claim 3, further comprising an ohmmeter that measures the resistance of the heating element.

5. The grilling device of claim 4, wherein the feedback information provided from the first temperature sensor to the digital controller includes a resistance measured by an ohmmeter.

6. The grilling device of claim 1, wherein the digital controller further comprises a digital memory and a computer processor, and a temperature control system comprising the digital controller and at least one of the first temperature sensor and the second temperature sensor is configured to maintain cold smoke due to smoldering of the wood fuel for at least five minutes.

7. The grilling device of claim 1, wherein the grilling device is configured to maintain smoldering of the wood fuel in the fire tank for at least ten minutes.

8. The grilling device of claim 1, wherein the grilling device is configured to burn lignin in the fire pot while maintaining the temperature within the cooking chamber between 70°f and 120°f for a period of at least 5 minutes.

9. A method for generating cold smoke in a barbecue apparatus for cooking food includes providing a barbecue apparatus including a firebox having an interior space, a heating element configured to ignite wood fuel in the interior space of the firebox, a blower configured to circulate oxygen into the interior space of the firebox, a first temperature sensor configured to sense a first temperature in the interior space of the firebox, a power source to supply power to the heating element and the blower, and a processor configured to regulate the power supplied to the heating element and the blower, igniting wood fuel in the interior space of the firebox by activating the heating element, sensing the first temperature with the first temperature sensor and transmitting firebox temperature information to the processor, intermittently igniting wood fuel by the heating element based on the firebox temperature information, in combination with intermittently increasing and decreasing an amount of oxygen circulated into the firebox to maintain smoldering of wood fuel in the firebox such that combustion of wood fuel cannot be maintained by oneself without an external heat source while maintaining a cold temperature of wood fuel by igniting wood fuel in a second cooking chamber arranged at least about 150 DEG F in a low cooking time of at least about a second cooking chamber of the barbecue apparatus.

10. The method of claim 9, wherein the grilling device further comprises a second temperature sensor disposed within the cooking chamber, and wherein the method further comprises measuring a second temperature with the second temperature sensor, transmitting temperature information about the second temperature to the processor, and adjusting the power supplied to the heating element and the blower based on the temperature information about the second temperature provided to the processor.

11. The method of claim 9, wherein the heating element comprises a first temperature sensor.

12. The method of claim 11, wherein sensing the first temperature comprises turning off the heating element once the wood fuel is ignited and measuring a resistance of the heating element, providing a resistance measurement to the processor, and converting the resistance measurement to the first temperature.

13. The method of claim 9, wherein the heating element is positioned outside of the interior space of the firebox, and igniting the wood fuel within the interior space of the firebox comprises blowing air onto the heating element and into the interior space of the firebox.

14. The method of claim 9, wherein the heating element is disposed at least partially within the interior space of the firebox, and igniting the wood fuel within the interior space of the firebox comprises bringing the wood fuel within the interior space of the firebox into direct contact with the heating element.

15. A barbecue apparatus for generating cold smoke for use in cooking or heating oF food, comprising a cooking chamber, a fire tank having an interior space, a heating element configured to ignite a wood fuel residing within the interior space oF the fire tank, a blower configured to circulate oxygen into the interior space oF the fire tank, a power source to provide power to the heating element and the blower, a processor, and a memory containing computer executable instructions that when executed cause the barbecue apparatus to perform the steps oF igniting the wood fuel within the interior space oF the fire tank by providing a first amount oF power to the heating element from the power source, providing a second amount oF power to the heating element, the second amount oF power being less than the first amount oF power, receiving a resistance signal from the heating element in the event oF the second amount oF power being applied to the heating element, converting the resistance signal to fire tank temperature information at the processor, and adjusting the power supplied to the heating element and the blower based on the fire tank temperature information, wherein the adjusting, by the heating element, ignites the wood fuel in combination with intermittently increasing and decreasing the amount oF oxygen circulated to the fire tank, prevents the wood fuel from entering the interior space oF the fire tank, continuously combusting wood fuel at a temperature oF at least 150 f, and maintaining a cool smoke from being generated in the combustion environment outside at the time oF at which no cold smoke is generated.

16. The grilling device of claim 15, wherein the grilling device is further configured to identify a smoke temperature of smoke within a cooking chamber of the grilling device, and to send information regarding the smoke temperature within the cooking chamber to the processor, wherein the processor adjusts the power supplied to the heating element and the blower based at least in part on the information regarding the smoke temperature within the cooking chamber, the cooking chamber including a space separate from an interior space of the fire pot.

17. The grilling device of claim 16, wherein the grilling device is further configured to change a speed of the blower or the screw feeder in response to information regarding a temperature of smoke in the cooking chamber.

18. The grilling device of claim 15, wherein the grilling device is further configured to change a speed of the blower in response to the fire tank temperature information.

19. The grilling apparatus of claim 15, wherein the grilling apparatus is further configured to change the speed of the screw feeder in response to the fire pot temperature information.

20. The grilling device oF claim 15, wherein the cold smoke is maintained below 100°f for at least five minutes.

21. The grilling device oF claim 15, wherein the cold smoke is maintained below 80°f for at least five minutes.