Abstract:
A mobile cooking apparatus is configurable and automatically controlled to regulate the cooking temperature. The cooking apparatus is configurable as to fuel source (liquid propane or charcoal), and the temperature control is adaptable to the selected fuel. Additionally, smoke flavor may be optionally used, and various adjuncts such as a rotisserie, grill and deep fryer may be included.

Description:
RELATED APPLICATIONS 
   This Non-Provisional Patent Application claims priority based on the Provisional Patent Application Ser. No. 60/545,202, filed Feb. 17, 2004. 

   TECHNICAL FIELD 
   The present invention relates to an outdoor cooking apparatus for on-site food preparation, and more particularly to a configurable cooking apparatus with automatic control of cooking temperature. 
   BACKGROUND OF THE INVENTION 
   Various outdoor cooking arrangements have been used for on-site food preparation at events such as private parties and picnics and public fairs and exhibitions. The food prepared for such events can include grilled items such as hamburgers and steaks, barbecued items such as whole chickens, and roasted items such as whole hogs. The heat is often provided by burning charcoal or liquid propane, and sometimes wood chips are also burned to give the food a smoke flavor. The most convenient cooking arrangement is in the form of a mobile unit that is towed to the food preparation site by a motor vehicle; see for example, the U.S. Pat. No. 5,988,158 to Schmidt, Jr. However, there remain health safety concerns about on-site outdoor food preparation because outdoor cooking devices typically include only manual temperature controls, and the operator may lack proper training in outdoor food preparation. Additionally, the cooking apparatus should be easy to use and configurable to satisfy different cooking requirements. 
   SUMMARY OF THE INVENTION 
   The present invention is directed to an improved cooking apparatus that is mobile, configurable and automatically controlled to regulate the cooking temperature. The cooking apparatus is configurable as to fuel source (liquid propane or charcoal), and the temperature control is adaptable to the selected fuel. Additionally, smoke flavor may be optionally used, and various adjuncts such as a rotisserie, grill and deep fryer may be included. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a side view of the mobile cooking apparatus of this invention, depicting a grill unit, a roaster unit and an electric control unit; 
       FIG. 2  depicts the cooking apparatus of  FIG. 1 , with the grill unit and roaster unit access doors opened; 
       FIG. 3  is an isometric view of the top and front of the cooking apparatus of  FIG. 1 . 
       FIG. 4  is a rear view of the cooking apparatus of  FIG. 1 , depicting the roasting unit, a slide-in burner, and a primary LP tank. 
       FIG. 5  is a cross-sectional view of the roaster unit of  FIG. 4 . 
       FIG. 6A  depicts a slide-in LP burner for the roaster unit. 
       FIG. 6B  depicts a slide-in charcoal burner for the roaster unit. 
       FIG. 7  is a side view of the mobile cooking apparatus of this invention, depicting the roaster unit, a smoker unit, and a deep frying unit. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring to the drawings, and particularly to  FIGS. 1-4 , the reference numeral  10  generally designates a mobile cooking apparatus according to the present invention. The cooking apparatus  10  is mounted on a wheeled trailer frame  12  so that it can be towed to any convenient location and parked as a stand-alone food preparation center. Stabilizer jacks  14 ,  16  are provided at each rear corner of the trailer frame  12  in addition to the usual tongue jack  18 . In the illustrated embodiment, the cooking apparatus  10  includes an LP grill unit  20 , a roaster unit  22 , an electrical control module  24 , a smoker unit  26  and a deep-fryer unit  28 . The deep-fryer unit  28  is designed for cooking large items such as a whole turkey, and includes a suitable pot  28   a . The roaster unit  22  is ventilated by a shielded stack  22   a , and the grill unit  20  is ventilated by a shielded stack  20   a . The grill unit  20  and deep-fryer unit  28  can be operated independently, and are not functionally coupled to the roaster unit  22  apart from their common mounting on the trailer frame  12 . For this reason, the grill unit  20 , the smoker unit  26  and the deep-fryer unit  28  may be considered as optional equipment. 
   A primary LP gas tank  29  supplies LP gas to the roaster unit  22 , and is located in a closed compartment  30  at the rear of the trailer frame  12  as shown in  FIG. 4 . The grill unit  20  and roaster unit deep-fryer unit  28  are supplied by a separate LP tank housed in a storage compartment  32  at the front of the trailer  12 . 
   The roaster unit  22  is the heart of the cooking apparatus  10 , and includes left and right bi-fold access doors  32 ,  34  as seen in  FIGS. 1-2 . A latch  36  locks the access doors  32 ,  34  in a closed position during transmit, and insulated handles  32   a ,  34   a  are mounted on each access door  32 ,  34  for ease of opening and closing. 
   According to the invention, the roaster unit  22  can be configured to operate on either LP gas or charcoal at the operator&#39;s discretion. Referring to  FIGS. 4-5 , the roaster unit  22  has a rear access opening  40  and a set of internal support rails  42 ,  44  for receiving and supporting a slide-in heating unit  46  or  48 . The operator simply decided upon the desired heat source (i.e., LP gas or charcoal) for the roaster unit  22 , and then installs the appropriate heating unit  46  or  48 . The heating unit  46  or  48  not in use may be conveniently stowed in one of two fender storage compartments  50  accessed by hinged covers  52 , as illustrated in  FIG. 3 . 
     FIGS. 6A-6B  respectively depict a slide-in LP heating unit  46  and a slide-in charcoal heating unit  48 . The heating unit  46 ,  48  have essentially identical exterior dimensions, each including a set of flanges  46   a / 48   a  designed to ride on the internal support rails  42 ,  44  of roaster unit  22 , and a handle  46   b / 48   b  designed to be grasped by the operator to facilitate their insertion and removal. 
   Referring to  FIG. 6A , the LP heating unit  46  includes an LP gas pipe  54  for supplying LP gas to each of several gas burners  56   a ,  56   b ,  56   c ,  56   d  distributed throughout the length of the unit, each being adjustable for gas flow restriction. Once the LP heating unit  46  is installed, the operator simply couples the stub  58  of gas pipe  54  to the primary LP tank  29  with a flexible gas hose (not shown), and regulates the gas flow to the burners  56   a - 56   d  via the tank valve  60 . 
   Referring to  FIG. 6B , the charcoal heating unit  48  includes an air pipe  62  for supplying auxiliary combustion air along the length of the unit via the periodic openings  64 . When the operator elects to use charcoal heating unit  48 , the stub  66  of air pipe  62  is coupled to a temperature controlled blower unit  110 , described below. Combustion air for the charcoal is supplied via the rear access opening  40 . 
   Referring to  FIG. 5 , the walls  22   b ,  22   c ,  22   d  of roaster unit  22  are insulated, and enclose an adjustable height grating  70  above the heating unit  46  or  48 . A grease shield  72  is interposed between the heating unit  46 / 48  and the grating  70 , and includes integral troughs  72   a ,  72   b  for collecting all liquids that drip from meat being cooked in the roaster unit  22 . The grease shield  72  is supported by interior brackets (not shown) formed on the front and rear faces of the roaster unit  22 , and is angled toward the rear of the trailer so that grease and other liquids collected in the troughs  72   a ,  72   b  flow out of drain pipes  74  or  76  protruding from the rear face of the roaster unit  22 . The bottom of the roaster unit  22  is V-shaped as shown, and an additional drain pipe  78  located at the bottom of the unit drains any liquids not caught by the troughs  72   a ,  72   b . A water pipe  84  disposed above the grating  70  has a number of spaced spray nozzles  86  for dowsing the interior of the roaster unit  22  with water in the unlikely event of a grease fire in the roaster unit  22 . The water pipe  84  terminates in a stub  88  on the rear of the roaster unit  22 , and can be coupled to a garden hose or other locally available water supply. A temperature probe  90  supported in a junction box  91  mounted on the rear face of the roaster unit  22  measures the air temperature inside the roaster unit  22 . The probe produces an electrical temperature signal, and the signal is supplied to control module  24  via line  92 . 
   Referring to  FIGS. 1 and 4 , the control module  24  includes a user interface panel  94 , a controller  96 , and a pair of electric motor driven blower units  110  and  112 . The blower units  110  and  112  are mounted below the interface panel  94 , and are activated by controller  96  to control the cooking temperature in roaster unit  22 , as explained below. The controller  96  may be mechanized with relay or solid state logic circuits or a programmed microprocessor, for example. The controller  96  receives inputs from temperature probe line  92  and a number of operator actuated switches  98  mounted on the interface panel  94 , and generates outputs for the blower units  110  and  112 , and a number of interface panel indicator lamps  100 . For example, the switches  98  may include a master power switch, a rotisserie control switch, a charcoal draft control switch and a roaster exhaust control switch. The panel  94  also includes a temperature gauge  102  that displays the temperature measured by the temperature probe  90 . For operator convenience roaster temperature gauges  104  and  106  are also provided on the front and rear faces of the roaster unit  22 . 
   The blower unit  110  is selectively activated by the controller  96  to exhaust air from the roaster unit  22 . The blower unit  110  includes an inlet  110   a  and an outlet  110   b . The inlet  110   a  is manually connected (with a flexible hose, for example) to an exhaust pipe  114  passing through the rear face of roaster unit  22 , so that activation of the blower unit  110  by controller  96  exhausts air from the interior of roaster unit  22  to the atmosphere via outlet  110   b . The roaster exhaust control switch on control interface panel  94  is selectively positioned to OFF or ON, and in the ON setting enables automatic control of the blower unit  110  by controller  96 . When the switch is in the ON position, the controller  96  activates the blower unit  110  to prevent the temperature in roaster unit  22  from exceeding a calibrated high temperature limit such as 400° F. In practice, the controller  96  turns on the blower unit  110  when the temperature measured by probe  90  exceeds the high temperature limit, and subsequently turns off the blower unit  110  when the measured temperature falls below a setpoint that is 5-10° F. below the high temperature limit. This control can be enabled whether the heat source is LP gas or charcoal. 
   The blower unit  112  is selectively activated by the controller  96  to supply supplemental combustion air to the heating unit  48  when the roaster unit  22  is being heated with charcoal. The blower unit  112  includes an inlet  112   a  and an outlet  112   b . The outlet  112   a  is manually connected (with a flexible hose, for example) to the air pipe stub  66  of heating unit  48  so that activation of the blower unit  112  by controller  96  supplies supplemental combustion air to the charcoal to increase the heat produced by the charcoal. The charcoal draft control switch on control interface panel  94  is selectively positioned to OFF or ON, and in the ON setting enables automatic control of the blower unit  112  by controller  96 . When the switch is in the ON position, the controller  96  activates the blower unit  112  to prevent the temperature in roaster unit  22  from falling below a low temperature limit such as 200° F. The controller  96  turns on the blower unit  112  when the temperature measured by probe  90  falls below the low temperature limit, and subsequently turns off the blower unit  112  when the measured temperature rises above a setpoint that is 5-10° F. above the low temperature limit. 
   Referring to  FIG. 7 , the smoker unit  26  is located adjacent the front panel of roaster unit  22 , and is coupled to the roaster unit  22  by a smoke pipe  130 . The smoker sidewalls support upper and lower slide-in trays  132 ,  134  and the access door  136  includes an adjustable draft damper mechanism  138 . Charcoal or the like is loaded into the lower slide-in tray  134 , and the upper tray  132  can be filled with water. If a smoke odor is desired, hickory chips or the like can be mixed in with the charcoal in the lower tray  134 . Air entering the damper mechanism  138  in access door  136  is combusted with the charcoal in the smoker unit  26 , and passes through the roaster unit  22  via smoke pipe  130 . The water in tray  132  adds moisture to the air in roaster unit  22  so that meat cooking in roaster unit  22  retains its moisture. 
   The grill unit  20  may include a deep-fryer for cooking small food items such as french-fried potatoes and vegetables, and a grating for hamburgers, sausages, and the like. Cooking heat is supplied by a number of individually adjusted LP gas burner units (not shown) supplied by an LP gas tank stowed in the compartment  32  as mentioned above. The access door  20   b  is provided with an insulated handle  20   c , and the door  20   b  is opens downward as shown in  FIG. 2 . A drain  120  at the base of the grill unit  20  drains grease and any other liquid passing through the grating. 
   In summary, the present invention provides a mobile cooking apparatus that is configurable and that addresses health safety concerns typically associated with on-site outdoor food preparation. While the present invention has been described with respect to the illustrated embodiment, it is recognized that numerous modifications and variations in addition to those mentioned herein will occur to those skilled in the art. Accordingly, it is intended that the invention not be limited to the disclosed embodiment, but that it have the full scope permitted by the language of the following claims.