Patent Publication Number: US-2021161160-A1

Title: Smoke generator

Description:
REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 15/942,631, filed Apr. 2, 2018, which is hereby incorporated by reference. U.S. patent application Ser. No. 15/942,631, filed Apr. 2, 2018, claims the benefit of U.S. Patent Application No. 62/480,743, filed Apr. 3, 2017, which are hereby incorporated by reference. 
    
    
     BACKGROUND 
     Smokers are popular devices that use indirect heat rather than direct heat to slowly cook and add a smoky flavoring to food. Generally, the heat for a smoker is generated by burning wood or charcoal. A commonly used method is to place a wood or charcoal biscuit on or above a heated plate. However, it may be difficult to control the temperature at which the biscuit is burned. Additionally, burning a biscuit may create an open flame and produce ash and tars that may contaminate the food. Using wood pellets may be an effective alternative to burning a biscuit or charcoal, but wood pellets can be expensive, as most wood pellet smokers require a large amount of pellets to create heat and smoke. Thus, there is a need for improvement in this field. 
     SUMMARY OF THE INVENTION 
     To address the issues presented above, a smoke generator that is able to produce smoke in a controllable and repeatable process without producing a flame was developed. The smoke generator is capable of generating smoke using heat that is independent of the heat used to cook food in the smoker. Therefore, the quality and quantity of smoke may be refined without affecting the food that is being cooked. 
     In one embodiment, the smoke generator is attached to a smoker and includes a housing having an interior that encloses a hopper for storing a smoking fuel. A portion of a fuel conveyor, such as an auger having an auger shaft and a helical portion wrapped around the auger shaft, is also positioned within the interior of the housing. The fuel conveyor is in communication with the hopper so that smoking fuel from the hopper may be fed to the fuel conveyor. 
     The fuel conveyor is operationally attached to a motor. Operation of the motor causes the smoking fuel held by the fuel conveyor to move along the length of the fuel conveyor. As the smoking fuel moves along the fuel conveyor, a heating element heats the fuel conveyer so that smoking fuel within the fuel conveyor is heated. As smoking fuel is heated, smoking fuel generates smoke that is used to flavor food within the smoker. The temperature of the heating element may be varied using a control panel. Also, the speed of the motor may be varied to control the dwell time of the smoking fuel within the fuel conveyor. Adjusting the temperature of the heating element and the dwell time of the smoking fuel may change the characteristics of the smoke that is generated. For example, the temperature at which the smoking fuel is heated may be sufficient to create smoke yet not high enough to create a flame, thereby reducing the production of ash and tars. 
     The smoke generator design as described and illustrated herein concerns a number of unique and inventive aspects. Some, but by no means all, of these unique aspects are summarized below. 
     Aspect 1 concerns a smoke generator including a fuel conveyor having a length, wherein the fuel conveyor moves a smoking fuel fed to the fuel conveyor. A heating element is configured to heat the fuel conveyer. The smoking fuel is heated as it moves along the length of the fuel conveyor so that the smoking fuel continuously generates smoke. 
     Aspect 2 concerns the smoke generator of any preceding aspect, and further comprises a housing and a hopper within the housing configured to hold the smoking fuel and to feed the smoking fuel to the fuel conveyor. 
     Aspect 3 concerns the smoke generator of any preceding aspect, and further comprises a motor operationally attached to the fuel conveyor. The operation of the motor causes the smoking fuel to move along the fuel conveyor. 
     Aspect 4 concerns the smoke generator of any preceding aspect, wherein the amount of time the smoking fuel is heated within the fuel conveyor may be adjusted by changing the speed of the motor. 
     Aspect 5 concerns the smoke generator of any preceding aspect, wherein the smoking fuel is wood pellets. 
     Aspect 6 concerns the smoke generator of any preceding aspect, wherein the fuel conveyor is at an oblique angle with respect to the housing. 
     Aspect 7 concerns the smoke generator of any preceding aspect, wherein the fuel conveyor is positioned at an angle with respect to the housing of 4-5 degrees. 
     Aspect 8 concerns the smoke generator of any preceding aspect, wherein the smoking fuel moves along the length of the fuel conveyor in approximately 10 minutes. 
     Aspect 9 concerns the smoke generator of any preceding aspect, wherein the fuel conveyor is an auger including an auger shaft and a helical portion wrapped around the auger shaft. Operation of the motor causes the auger shaft to rotate and rotation of the auger shaft causes the smoking fuel to move along the length of the auger. 
     Aspect 10 concerns the smoke generator of any preceding aspect, further comprising a conveyor casing surrounding the fuel conveyor. The conveyor casing includes an inner pipe and an outer pipe. 
     Aspect 11 concerns the smoke generator of aspect 10, wherein the inner pipe includes an inner vent hole. 
     Aspect 12 concerns the smoke generator of aspect 10, wherein the outer pipe includes one or more outer vent holes. 
     Aspect 13 concerns the smoke generator of any preceding aspect, wherein the heating element is an electric heat tape wrapped around at least a portion of the fuel conveyor. 
     Aspect 14 concerns a method of generating smoke for cooking including feeding smoking fuel to a fuel conveyor having a length. The fuel conveyor is operationally attached to a motor. Next, at least a portion of the length of the fuel conveyer is heated, in turn heating the smoking fuel. The motor is then operated to move the fuel conveyor so the smoking fuel moves along the length of the fuel conveyer. Heating the smoking fuel as it moves along the length of the fuel conveyor generates smoke. 
     Aspect 15 concerns the method of generating smoke of aspect 14, further comprising heating the fuel conveyor at a temperature between 450° F. and 500° F. 
     Aspect 16 concerns the method of generating smoke of aspect 14 or aspect 15, wherein operating the motor at different speeds adjusts the dwell time of the smoking fuel within the fuel conveyer. 
     Aspect 17 concerns the method of generating smoke of any of aspects 14-16, wherein moving the smoking fuel along the length of the fuel conveyor takes approximately 10 minutes. 
     Aspect 18 concerns the method of generating smoke of any of aspects 13-17, wherein smoking fuel is fed to the fuel conveyor from a housing. The fuel conveyor is positioned at an oblique angle with respect to the housing. 
     Aspect 19 concerns the method of generating smoke of any of aspects 13-18, wherein the motor is operated noncontinuously at predetermined time intervals. 
     Aspect 20 concerns the method of generating smoke of any of aspects 13-19, further comprising heating the fuel conveyor at a temperature between 650° F. and 750° F. 
     Aspect 21 concerns the method of generating smoke of any of aspects 13-19, wherein the fuel conveyor is heated by a heating element to a smoking temperature. The heating element is deactivated to stop producing heat when the fuel conveyor reaches the smoking temperature. 
     Aspect 22 concerns the method of generating smoke of aspect 21, wherein the heating element is reactivated to produce heat when the temperature of the fuel conveyor is reduced to a threshold temperature that is less than the smoking temperature. 
     Further forms, objects, features, aspects, benefits, advantages, and embodiments of the present invention will become apparent from a detailed description and drawings provided herewith. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view of a smoker. 
         FIG. 2  is a perspective view of the smoker of  FIG. 1 . 
         FIG. 3  is a side view of a smoke generator from the smoker of  FIG. 1 . 
         FIG. 4  is a bottom view of a housing of a smoke generator from the smoker of  FIG. 1 . 
         FIG. 5  is a front view of a housing of a smoke generator from the smoker of  FIG. 1 . 
         FIG. 6  is a top cross-sectional view of the smoke generator of  FIG. 3 . 
         FIG. 7  is a side cross-sectional view of the smoke generator of  FIG. 3   
         FIG. 8  is a side view of an auger from the smoke generator of  FIG. 3 . 
         FIG. 9  is a flowchart for a method for generating smoke with the smoker of  FIG. 1 . 
         FIG. 10  is a cross-section side view of the smoke generator of  FIG. 3  with smoking fuel. 
         FIG. 11  is a front view of an embodiment of a smoke generator. 
         FIG. 12  is a cross-sectional side view of the smoke generator of  FIG. 11 . 
         FIG. 13  is a side view of an outer pipe for the smoke generator of  FIG. 11 . 
         FIG. 14  is a side view of an inner pipe for the smoke generator of  FIG. 11 . 
         FIG. 15  is a side view of an auger for the smoke generator of  FIG. 11 . 
         FIG. 16  is a front view of a hopper and a hopper feed extension for the smoke generator of  FIG. 11   
         FIG. 17  is a front view of a cover for the housing of the smoke generator of  FIG. 11 . 
         FIG. 18  is a schematic diagram of a smoker including the smoke generator of  FIG. 11 . 
         FIG. 19  is a flow chart illustrating a control process for the smoke generator of  FIG. 11 . 
     
    
    
     DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS 
     For the purposes of promoting an understanding of the principles of the disclosure, reference will now be made to the embodiments illustrated and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended, such alterations, modifications, and further applications of the principles being contemplated as would normally occur to one skilled in the art to which the invention relates. 
     The reference numerals in the following description have been organized to aid the reader in quickly identifying the drawings where various components are first shown. In particular, the drawing in which an element first appears is typically indicated by the left-most digit(s) in the corresponding reference number. For example, an element identified by a “100” series reference numeral will likely first appear in  FIG. 1 , an element identified by a “200” series reference numeral will likely first appear in  FIG. 2 , and so on. 
     Now referring generally to the drawings,  FIG. 1  illustrates an example of a smoker  100 . Smoker  100  includes a cabinet  105  and a smoke generator  125  attached to one side of cabinet  105 . Smoke generator  125  may be operated as a cold smoker that creates smoke to give food in cabinet  105  a smoky flavor. Smoke generator  125  may also be used while smoker  100  heats and cooks food within cabinet  105 . Smoker  100  provides indirect heat to food in cabinet  105 . Indirect heat requires greater cooking time than direct heat, but the indirect heat may reduce the risk of the food drying out. Alternatively or additionally, the smoke from smoke generator  125  may add additional smoke flavoring to the food. As shown in this embodiment, there is one smoke generator  125 ; however, in other embodiments, smoker  100  may include multiple smoke generators. 
     Smoke generator  125  uses a smoking fuel to generate smoke. In some embodiments, the smoking fuel may be a pellet fuel, such as wood pellets. A wood pellet is generally a small, compressed mass of compacted wood such as sawdust or recycled wood waste. The pellets are often cylindrically shaped but could take other shapes or be irregularly shaped. Other varieties of smoking fuels may also be used. For example, the smoking fuel may be wood chips, sawdust, herbs, spices, a blend of herbs and spices, coffee beans, or any other suitable material for generating a flavored smoke. 
     In some embodiments, smoke generator  125  creates smoke using a different heat source than the heat that is used to cook food within cabinet  105 . Separating the heating smoke generator  125  and cabinet  105  allows the quality and quantity of smoke created by smoke generator  125  to be refined independently of producing heat for cooking food in cabinet  105 . In these embodiments, the smoking fuel is not burned to create heat for cooking the food in cabinet  105 , but instead used only to create smoke for imparting flavor to the food in cabinet  105 . 
     As shown in  FIG. 2 , cabinet  105  includes a cooking area  210  and a control area  215 . Cooking area  210  may include a door  220  that allows a user access to cooking area  210  to insert or remove food. Door  220  may be sealed shut while cooking so smoke cannot escape from cooking area  210 . 
     Control area  215  holds electrical wiring and other components necessary for controlling the operation of smoker  100 . As an example, control area  215  may include a control panel  216 , such as a touch screen, allowing a user to control cook time, temperature, and other cooking operations. Control area  215  may also include a drawer  218  for accessing a reservoir for spent smoking fuel. 
       FIG. 3  shows an example of a smoke generator  125 . Smoke generator  125  includes a housing  310 , a hopper feed  320  and a conveyor casing  330 . Housing  310  includes an interior that contains the components of smoke generator  125  needed for creating smoke. In some embodiments, housing  310  may be made from stainless steel, but any other desired material may be used. 
     Hopper feed  320  is positioned on top of housing  310 . A smoking fuel, such as wood pellets, may be inserted into hopper feed  320  for access to the interior of housing  310 . Smoking fuel may be added manually by a user, or hopper feed  320  may be configured to receive a container including the smoking fuel, whereby the container provides a supply of the smoking fuel as the smoking fuel is used by smoke generator  125 . Although hopper feed  320  is shown on the top of housing  310 , in other embodiments, hopper feed  320  may be positioned on one of the sides of housing  310 . 
     Conveyor casing  330  extends from housing  310 , so that smoke created by smoke generator  125  may be delivered to cooking area  210 . A heating element, such as electric heat tape  335  is wrapped around at least a portion of conveyor casing  330  that is exterior of housing  310 . Electric heat tape  335  operates to heat the interior of conveyor casing  330 . In some embodiments, an insulation layer  338  may be wrapped around the portion of conveyor casing  330  that is exterior of housing  310  and heat tape  335 . Insulation layer  338  prevents a user from burning themselves on heated conveyor casing  330  and heat tape  335  when smoker  100  is in use. Heat tape  335  may be connected to control panel  216  to allow a user to adjust the temperature generated by heat tape  335 . In some embodiments, the heat provided to conveyor casing  330  may be regulated by a rheostat or a programmable logic controller that adjusts the current supplied to the heat tape  335 . Adjusting the current supplied to heat tape  335  can adjust the temperature of the conveyor casing  330 . 
     In some embodiments, the heating element may be wrapped around a 4.25 inch length of conveyor casing  330  that is exterior of housing  310 . As an example, HTS/Amptek Duo-Tape® Heavy Insulated Tape may be used for heat tape  335  as the heating element. 
     A bottom view of housing  310  of smoke generator  125  is shown in  FIG. 4 . Housing  310  has a rectangular footprint, but in other embodiments, housing  310  may be shaped differently. For example, housing  310  may be hexagonal. A top view of housing  310  of smoke generator  125  is shown in  FIG. 5 . In this embodiment, hopper feed  320  is positioned on the top surface of housing  310 . 
       FIG. 6  illustrates a top, cross-sectional view of smoke generator  125 . Housing  310  has an interior  610  that includes a hopper  620 . Hopper  620  is engaged with hopper feed  320 , so that material inserted through hopper feed  320  is collected in hopper  620 . A cavity  624  between hopper  620  and the portion of conveyor casing  330  within the interior of housing  310  allows material within hopper  620  to be fed into the interior of conveyor casing  330 . A release button  625  on housing  310  allows a user to push button  625  to empty smoking fuel from within conveyor casing  330 . 
     A cross-sectional view of smoke generator  125  is shown in  FIG. 7 . Interior  610  within housing  310  includes hopper  620  and a motor  730 . Motor  730  is operationally attached to a fuel conveyor, such as an auger  740 , positioned within conveyor casing  330 . Auger  740  includes an auger shaft  745  and a helical portion  750  wrapped around auger shaft  745  (see  FIG. 8 ). 
     The rotation rate of motor  730  may be variable to allow the dwell time of the smoking fuel within the heated conveyor casing  330  to be adjusted. A slower rotation rate increases the dwell time of the smoking fuel and reduces the amount of smoking fuel used during cooking. However, increased dwell time increases the amount of heat transferred to the smoking fuel and increases the risk of burning or creating a flame that produces ash or tar. A user may also control the temperature of the smoking fuel by adjusting the dwell time of the smoking fuel on the fuel conveyer. Longer dwell times lead to higher temperatures while shorter dwell times produce lower temperatures. The user can choose a dwell time so the smoking fuel reaches a desired temperature, such as a temperature where the smoking fuel produces smoke but does not produce a flame. 
     Auger  740  is positioned at an oblique, upward angle, A, with respect to housing  310 . This angle helps to produce a chimney effect that encourages the smoke to rise upward, to fill cooking area  210  of the cabinet  105 . The angle also helps to reduce back feed of the smoke toward smoke generator  125 . In one embodiment, auger  740  has a diameter of 1.5 inches, a length of 12 inches and a pitch of 1 inch, so that the angle of auger  740  with respect to housing  310  is approximately 4-5 degrees. 
     A reservoir  770  is positioned below the end of auger  740  that is exterior of housing  310 . Once the smoking fuel has been rotated through the length of auger  740 , the spent fuel is deposited into reservoir  770 . Reservoir  770  may contain a cooling liquid  775 , such as water, that reduces the heat of the fuel and allows for safe disposal of the spent fuel after use. 
     A method for generating smoke  900  is shown in  FIG. 9 . A smoking fuel, such as wood pellets  1010  (see  FIG. 10 ), is inserted  910  into hopper feed  320  so that the smoking fuel is then held within hopper  620 . Hopper  620  is in communication with conveyor casing  330  and auger  740  so that wood pellets  1010  held in hopper  620  are fed  920  to auger  740 . Electric current is provided to heat tape  335  so that heat is applied  930  to conveyor casing  330  and auger  740  so the wood pellets  1010  within conveyor casing  330  are heated. The heat and smoke produced from heating the wood pellets  1010  is directed to cooking area  210  of cabinet  105  to provide smoke flavoring to any food within cooking area  210 . 
     As the wood pellets  1010  within conveyor casing  330  are heated, motor  730  rotates 940 auger shaft  745  and helical portion  750  to move the wood pellets  1010  along the length of auger  740 . When a wood pellet reaches the end of auger  740 , the spent pellet is disposed of in stage  950  by dropping the pellet into reservoir  770  that includes a cooling liquid, such as water. The cooling liquid in reservoir  770  reduces the temperature of the pellet and helps to mitigate the risk of a fire. 
     The wood pellets are heated to a temperature that produces smoke, but the temperature is maintained below the ignition point of the wood pellets so that a flame does not form. This reduces the risk of producing tars or ash that may contaminate the food being cooked. Also, the risk of a fire is greatly reduced because there are no open flames created by the smoke generator. In some embodiments, the preferred temperature operating range is 450° F. to 475° F. An optional safety limit may be set so that the operating temperature does not exceed 500° F. In some embodiments, this temperature range combined with the setup of smoke generator  125  can produce smoke within 15 minutes of starting operation. The temperature setting for smoker  100  may be set to a fixed temperature or, in some embodiments, the temperature may be adjustable by the user. 
     In one embodiment, motor  730  is configured to rotate auger shaft  745  at a speed of 0.5 rotations per minute so that a single wood pellet has a dwell time in auger  740  of approximately 10 minutes. The feed time of pellets from hopper  620  to auger  740  is 0.25 pounds of pellets per hour. For typical wood pellets having a diameter of about ⅛ inches and a length of ½ inches, this configuration allows for only about 2 pounds of pellets to be used for 8 hours of cooking time. This provides an advantage over other smokers that may require more pellets for the same amount of smoke time. 
     In some embodiments, wood pellets used as smoking fuel may be pre-packaged in a container such as a canister. The canister may be configured to fit on top of hopper feed  320  to provide a supply of smoking fuel as smoke generator  125  is operated without requiring manually adding additional pellets. The pre-packaged pellets may include a pre-determined quantity needed for a specified smoking time. For example, the pellets may come in a canister that includes enough pellets for 4 hours of smoking. Other canisters may have as many pellets as needed for 2, 6, or 8 hours of smoking. In some embodiments, the canisters may be clear to allow a user to see how much smoking fuel is left in the canister as it is being used. 
     An embodiment of a smoke generator  1100  is shown in  FIGS. 11-12 . Smoke generator  1100  includes a housing  1110 , a hopper  1120 , and a conveyor casing  1130 . Housing  1110  includes an interior that contains the components of smoke generator  1100  needed for creating smoke. In some embodiments, housing  1110  is made from stainless steel, but any other desired material may be used. 
     A bottom portion of hopper  1120  is positioned within housing  1110  and a top portion of hopper  1120  extends outside of housing  1110 . Hopper  1120  includes an open interior area for holding smoking fuel. In some embodiments, hopper  1120  includes a hopper feed extension  1125 . A smoking fuel, such as wood pellets, is inserted into hopper feed extension  1125  so that the smoking fuel is fed into hopper  1120  within the interior of housing  1110 . Smoking fuel may be added manually by a user, or hopper feed extension  1125  may be configured to receive a container including the smoking fuel, whereby the container provides a supply of the smoking fuel as the smoking fuel is used by smoke generator  1100 . 
     Conveyor casing  1130  encloses a fuel conveyor that extends from housing  310 , so that smoke created by smoke generator  1100  is delivered to the cooking area of a cabinet. Conveyor casing  1130  includes an outer pipe  1305  (see  FIG. 13 ) that has a hopper end  1308  and a cabinet end  1312 . Hopper end  1308  of outer pipe  1305  is attachable to hopper  1110  and cabinet end  1312  is attachable to a cabinet. Outer pipe  1305  includes an outer wall  1316  that defines an opening  1318  that extends from the hopper end  1308  to the cabinet end  1312 . One or more outer vent holes  1322  are defined through the outer wall  1316  of outer pipe  1305 , allowing heated gas within opening  1318  to escape to the surrounding environment and preventing the heated gas from entering into hopper  1110  and prematurely burning the smoking fuel held within hopper  1110 . 
     An inner pipe  1405  (see  FIG. 14 ) fits at least partially within the opening  1318  of outer pipe  1305 . Inner pipe  1405  includes a hopper end  1408  and a cabinet end  1412  that correspond to the hopper end  1308  and the cabinet end  1312  of outer pipe  1305 . Inner pipe  1405  includes an outer wall  1416  that defines a hollow interior pathway  1418  that extends from the hopper end  1408  to the cabinet end  1412  of inner pipe  1405 . An inner vent hole  1422  is defined through a portion of the outer wall  1416  of inner pipe  1405 . Inner vent hole  1422  promotes a chimney effect within inner pipe  1405  allowing colder air to enter inner pipe  1405  to push heated air within interior pathway  1418  out of the cabinet end  1412  of inner pipe  1405  and into the cabinet of the smoker. 
     A heating element, such as electric heat tape or trace tape  1426  is wrapped around a portion of inner pipe  1405  beginning at the cabinet end of inner pipe  1405  and extends a length, L, along the inner pipe  1405 . The trace tape  1426  does not extend to the hopper end  1408  of the inner pipe  1405  to prevent heat from the trace tape  1426  from entering the hopper  1110  and burning the smoking fuel held within hopper  1110 . In some embodiments, the length L that the trace tape  1426  is wrapped around the inner pipe  1405  is equal to six inches from the cabinet end  1412  of inner pipe  1405 . 
     An auger  1505 , as shown in  FIG. 15 , is positioned within the interior pathway  1418  of inner pipe  1405 . Auger  1505  includes an auger shaft  1510  and a helical portion  1515  that is wrapped around auger shaft  1510 . A housing end  1522  of auger  1505  attaches to the housing  1110  of smoke generator  1100  and a cabinet end  1526  of the auger  1505  is attached to the cabinet of a smoker to deliver smoke to the cabinet. Smoking fuel is fed from hopper  1110  into the interior pathway  1418  of inner pipe  1405  where the smoking fuel comes into contact with auger  1505 . As auger  1505  is rotated, helical portion  1515  moves the smoking fuel linearly along the auger shaft  1510 . In some embodiments, the helical portion  1515  of auger  1505  near the housing end  1522  is tapered so that the diameter of helical portion  1515  at the housing end is smaller than the diameter of the helical portion  1515  at the cabinet end  1526 . The tapered helical portion  1515  allows for easier pick up of the smoking fuel as it exits the housing  1110  and enters the conveyor casing  1130 . 
     Auger  1505  and conveyor casing  1130  are positioned at an oblique, upward angle, A, with respect to housing  1110  (see  FIG. 12 ). This angle helps to produce a chimney effect that encourages smoke to rise upward, to fill cooking area  210  of the cabinet  105 . The angle also helps to reduce back feed of the smoke toward smoke generator  1100 . 
       FIG. 16  illustrates the hopper  1120  of smoke generator  1100 . The hopper  1120  includes an entrance section  1604  and an exit section  1608 . Hopper feed extension  1125  is attached to hopper  1120  so that hopper feed extension  1125  extends from entrance section  1604 . Hopper feed extension  1125  provides extra storage area for smoking fuel that is stored in hopper  1120  and can make it easier for smoking fuel to be added to hopper  1120 . The exit section  1608  is positioned within housing  1110  when hopper  1120  is attached to housing  1110  and includes a cavity  1612  that feeds smoking fuel within hopper  1120  to the conveyor casing  1130 . In this embodiment, exit section  1608  is concave; however in other embodiments exit section  1608  may have any suitable shape. 
     A cover  1705  for housing  1110  is shown in  FIG. 17 . Cover  1705  defines a conveyor casing opening  1708  for receiving conveyor casing  1130 . Attachment openings  1712  surrounding conveyor casing opening  1708  provide attachment points for securing a plate or other form of covering to seal the conveyor casing opening  1708  after the conveyor casing  1130  has been received. Cabinet slots  1716  are defined through cover  1705  and allow clearance for bolts or other features that may be used to attach housing  1110  to the cabinet of a smoker. 
     A controller  1804  (see  FIG. 18 ) is used to control the supply of power to smoke generator  1100 . In some embodiments, the controller is a programmable logic controller (PLC). However, in other embodiments, the controller may be a circuit board or other suitable type of control instrument. In some embodiments, controller  1804  only controls whether smoke generator  1100  is on or off, while a separate controller  1806  is used to control the operation of smoke generator  1100 . In these embodiments, controller  1806  controls the speed of auger  1505  and controls the supply of electricity to trace tape  1426 . 
     A thermocouple  1808  may be included near trace tape  1426  to provide temperature data to a controller. In some embodiments, it is preferred that the temperature within inner pipe  1405  for heating the smoking fuel is maintained between 650° F.-750° F. However, in other embodiments the maximum temperature for heating the smoking fuel may be increased to 850° F. or up to 1000° F. Heating the smoking fuel at a temperature below this range could produce bad smoke, while heating the smoking fuel to a temperature above this range could create bitter or dirty smoke or start to combust the smoking fuel. 
     As an additional safety measure, a fuse may be included to break resistance to the trace tape  1426  if the electrical current to the trace tape  1426  becomes too high. The fuse prevents the temperature of the inner pipe from exceeding a determined maximum temperature. This maximum temperature may be a temperature at which the smoking fuel starts to combust and create a flame rather than just producing smoke. 
     Thermocouples or temperature sensors may be included to measure the temperature of other portions of the smoke generator  1100 . In some embodiments, a temperature sensor  1812  is included in the hopper within the housing  1110  to monitor the temperature of the smoking fuel held within the hopper. In one example, a temperature sensor measures the temperature within the portion of the housing  1110  below the conveyor casing  1130  to monitor possible overheating and burning of the smoking fuel within the hopper. At a certain temperature measured by the temperature sensor, such as 100° F., the controller cuts power to the trace tape  1426  to stop heating and prevent further overheating of the housing  1110 . 
     A flow chart  1900  illustrating a control process for the smoke generator  1100  is shown in  FIG. 19 . In a first stage  1905 , full power is provided to the trace tape  1426  until the inner pipe  1405  reaches a minimum temperature. As an example, the minimum temperature for some embodiments is 625° F. 
     In a second stage  1910 , the power to the trace tape  1426  is toggled on and off for set time intervals to slowly raise the temperature within the inner pipe  1405  to a desired smoking temperature. In some embodiments, the time interval for activating the power to the trace tape  1426  is the same as the time interval for deactivating the power to the trace tape  1426 . In other embodiments, the time intervals for activating and deactivating the power to the trace tape  1426  are different. As a specific example, in some embodiments, the time intervals are ten seconds with power and three seconds without power. 
     The smoking temperature may be any desired temperature that is suitable for heating the smoking fuel and generating smoke. For example, it has been found that a smoking temperature of 725° F. produces an optimal flavor profile for certain meats and other foods. At this temperature, the smoking fuel is heated sufficiently to create good, flavorful smoke. Higher temperatures can ignite the smoking fuel. Cooking at lower temperatures produces bad smoke, such as a bitter or dirty smoke that will produce an unwanted flavor. 
     In a third stage  1915 , power to the trace tape  1426  is turned off when the temperature of the inner pipe  1405  reaches the desired smoking temperature. Once power to the trace tape  1426  is deactivated, the temperature may continue to increase after power to the trace tape  1426  has turned off while residual heat is still present. However, eventually the temperature begins to decrease to a temperature below the smoking temperature as heat is no longer supplied from the trace tape  1426 . 
     In a fourth stage  1920 , at a certain threshold temperature below the smoking temperature, power is supplied to the trace tape  1426  to reheat the inner pipe  1405  to the smoking temperature. As an example, the threshold temperature may be 5° F. below the smoking temperature. To reheat the inner pipe  1405  to the desired smoking temperature, power may be supplied to the trace tape  1426  in the same manner as it is supplied to the trace tape  1426  in the second stage  1910  so that power is toggled on and off in desired time intervals. In some embodiments, the time intervals are the same as in the second stage  1910  so that power is provided for ten seconds and then turned off for three seconds. After the temperature of the inner pipe  1405  returns to the smoking temperature, the power to the trace tape  1426  is turned off until the temperature of inner pipe  1405  reduces to the threshold temperature again. 
     The intermittent supply of power to the trace tape  1426  keeps the inner pipe  1405  at a suitable range for generating smoke. Turning off the supply of power keeps the inner pipe  1405  from becoming too hot so that the smoking fuel is ignited, and turning the supply of power back on at a given threshold temperature keeps the inner pipe  1405  from becoming too cold and producing bad smoke. 
     The controller  1806  controls the dwell time and the feed rate of the smoking fuel within the inner pipe  1405  through operation of the auger  1505 . In one example, the controller  1804  operates the motor  730  for five seconds and then turns off the motor  730  for ten seconds to let the smoking fuel rest within the inner pipe  1405 . When activated, the motor  730  is operated at a speed of 1 rotation per minute, so the effective speed of the motor is 0.33 rotations per minute when the motor  730  is activated for five seconds and then deactivated for ten seconds. This setup allows for the use of roughly 1 cup of wood pellets per hour when wood pellets are used as the smoking fuel. Although wood pellets are given as a representative smoking fuel, other types of smoking fuels such as chunks of hardwood may be used in smoke generator  1100 . 
     A consistent smoke is created by controlling the dwell time and the temperature of the smoking fuel within the auger  1505 , reducing the risk that bad smoke is imparted to the food being cooked in the cabinet of the smoker. Operation of the auger  1505  ensures that a suitable amount of smoking fuel is used to create the smoke and reduces the risk of using either too much or too little smoking fuel. In some instances, less smoking fuel is used during cooking as the smoking fuel is not burned too quickly and the risk of using too much smoking fuel while cooking is reduced by controlling operation of the auger  1505  at a predetermined feed rate. 
     In some embodiments, different temperature and dwell time settings are programmed into controller  1804  for cooking different types of food. In these embodiments, each of the individual settings is optimized for cooking a specific a type of meat or a specific vegetable for a certain time and certain temperature that provides good taste. 
     While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected.