Abstract:
A speed cooking with gas flow by-pass for radiant mode. A speed cooking oven with radiant mode is disclosed comprising a cooking cavity, a controller, thermal heating source, blower assembly, air directing means, a vent assembly and a gas by-pass system. Hot gas is circulated by the blower motor assembly into the oven cavity where the hot air is directed in a manner wherein a conflicting, colliding turbulent gas flow is directed at a food product providing for the rapid cooking of food products. Alternatively, gas may be diverted around the cooking cavity and maintained at the same temperature, lower temperature or elevated temperature as compared to the cooking cavity without having a direct effect on the food product being cooked.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     The present application claims priority to International Application No. PCT/US2005/035605 filed 5 Oct. 2005; claims priority to U.S. application Ser. No. 11/098,280 filed 4 Apr. 2005; claims priority to International Application No. PCT/US2006/009075 filed 14 Mar. 2006 and claims priority to U.S. application Ser. No. 11/392,050 filed 29 Mar. 2006. Upon entry into the National Stage in the United States of America, the present application will be a continuation-in-part of U.S. application Ser. No. 11/098,280 filed 4 Apr. 2005; will be a continuation-in-part of U.S. application Ser. No. 10/614,268 filed 7 Jul. 2003; will be a continuation-in-part of U.S. application Ser. No. 10/614,532 filed 7 Jul. 2003; and will be a continuation-in-part of U.S. application Ser. No. 11/392,050 filed 29 Mar. 2006.  
         [0002]     The present application contains technical disclosure in common with International Application No. PCT/US2003/021225 filed 5 Jul. 2003; contains technical disclosure in common with International Application No. PCT/US2005/007261 filed 7 Mar. 2005; contains technical disclosure in common with U.S. Provisional Application No. 60/394,216 filed 5 Jul. 2002; contains technical disclosure in common with PCT/US2004/035252 filed 21 Oct. 2004; contains technical disclosure in common with International Application No. PCT/US2005/035605 filed 5 Oct. 2005, contains technical disclosure in common with International Application No. PCT/US2006/009075 filed 14 Mar. 2006, contains technical disclosure in common with U.S. Provisional Application No. 60/513,110 filed 21 Oct. 2003; contains technical disclosure in common with U.S. Provisional Application No. 60/513,111 filed 23 Oct. 2003; contains technical disclosure in common with U.S. Provisional Application No. 60/614,877 filed 30 Sep. 2004; contains technical disclosure in common with U.S. Provisional Application No. 60/551,268 filed 8 Mar. 2004; contains technical disclosure in common with U.S. Provisional Application No. 60/615,888 filed 5 Oct. 2004; and contains technical disclosure in common with U.S. Provisional Application No. 60/550,578 filed 5 Mar. 2004.  
         [0003]     All of the applications set forth above are incorporated herein by reference as if fully set forth. 
     
    
     FIELD OF THE INVENTION  
       [0004]     The present invention relates to re-circulating speed cooking ovens with a radiant mode wherein gas flow may be heated or cooled without directly affecting a food product that may be cooking during such heat up or cool down of the gas flow.  
       DESCRIPTION OF RELATED ART  
       [0005]     Speed cooking ovens generally employ the use of electric resistance elements to heat gas flow. As used herein the term “gas flow” refers to any fluid mixture suitable for cooking food products. As such, it is a requirement that gas flow be present over the heating elements whenever these elements are on. In those instances wherein a food product is being cooked and finished off, it may be desirable to maintain oven temperature without the need for air flow across the food product and prior ovens do not allow for this requirement.  
       SUMMARY OF THE INVENTION  
       [0006]     This invention relates to ovens for cooking of food products. In particular, this invention combines the ability to cook a food product while at the same time increasing or decreasing the temperature of the gas flow without directly affecting the food product in the oven cavity. Currently, it is a requirement that in order to increase or decrease the temperature of gas flow available for cooking, a food product being cooked will be impacted by such heat up or cool down of the gas flow. The invention allows for gas flow circulation around the oven cavity without flowing to the food product within the oven cavity.  
         [0007]     Additional objects, features and advantages of the present invention will become readily apparent from the following detailed description of the exemplary embodiment thereof, when taken in conjunction with the drawings wherein like reference numerals refer to corresponding parts in the several views. 
     
    
     DESCRIPTION OF THE DRAWINGS  
       [0008]     The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein:  
         [0009]      FIG. 1  is a front view of the oven with by-pass gas flow;  
         [0010]      FIG. 2  is a side view of the oven during normal cooking with no by-pass;  
         [0011]      FIG. 3  is an enhanced view of the left side gas system;  
         [0012]      FIG. 4  is an enhanced view of the right side gas system;  
         [0013]      FIG. 5  is a top view of the oven.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0014]     An exemplary version of the speed cook oven with radiant mode is shown in  FIGS. 1-5 . Appliance  101  includes an oven cavity  102  generally defined by a top wall  103 , a bottom wall  104 , left side wall  105 , right side wall  106 , a back wall  194  and a front wall  195 . Oven cavity  102  also has associated therewith an access opening  107  through which food items  110  may be placed within oven cavity  102  upon cooking rack  108   a ,  FIG. 1 . Although shown as an oven with one rack  108   a , the invention may be practiced wherein multiple racks are utilized and although rack  108   a  is shown as a free-standing cooking rack, it may also be supported by the oven side walls. Cooking appliance  101  has a hinged door  109  pivotally attached to the oven front for closing the cooking section opening  107  during cooking operation. Hinged door  109  may be swung between an open position wherein the door allows access to oven cavity  102  and a closed position wherein the door covers the opening into oven cavity  102 . Although illustrated as a hinged door pivotally attached at the left side of the front of the oven, the door may be hinged on the right side, bottom side or top side.  
         [0015]     Referring to  FIG. 5 , the speed cooking oven is comprised of two independent gas transfer systems, described herein as a left gas transfer system and a right gas transfer system wherein left gas transfer system delivers gas to and from the left side of the oven cavity  102 , and right gas transfer system delivers gas to and from the right side of the oven cavity  102 . Although each gas transfer system is described separately, the systems are identical in their configuration (although is not required that they be identical) and operation and serve to distribute gas to the respective sides of oven cavity  102 . Oven cavity  102  also has associated therewith vent tube  171  which allows for the passage of vent gas from oven cavity  102  to atmosphere. Affixed within vent tube  171  is odor filter  172 .  
         [0016]     Gas is transferred to and from the left side of oven cavity  102  via a left gas transfer system, which is comprised of a left gas transfer section  115   a , extending from the front to back of oven top wall  103 , along the left side of top wall  103 . In fluid connection with left gas transfer section  115   a  is top gas egress opening  112 , which is open to, and in fluid connection with oven cavity  102  through top wall  103 . Top gas egress opening  112  is substantially rectangular, although other geometries may be utilized, and is centrally located within oven top wall  103  and provides for the passage of gas from oven cavity  102  into left gas transfer section  115   a , as gases are removed from oven cavity  102  through top egress gas egress opening  112 . Located within left gas transfer section  115   a  is left grease extractor  113   a . As gas is drawn through top gas egress opening  112 , the gas passes across left heating means  114   a , prior to entry in and through left grease extractor  113   a . Heating means  114   a  may include a direct fired thermal energy source, indirect fired thermal energy, propane, natural gas, electric resistance heating elements, and other thermal means, and applicant intends to encompass within the language any structure presently existing or developed in the future that performs the same function. After the gas is drawn across left heating means  114   a  and through left grease extractor  113   a , it is then drawn through left odor filter  143   a  and into left gas transfer section  115   a . Alternate locations for left odor filter  143   a  can be utilized within the gas flow path and the location of the left odor filter  143   a  adjacent left grease extractor  113   a  is not required. In fluid connection with, and located within left gas transfer section  115   a  is a left gas accelerator, illustrated as left blower wheel  116   a . Connected to left blower wheel  116   a  is blower motor shaft  190   a , which is driven by a direct shaft from electric motor  191   a . Other means may be employed for coupling blower wheel  116   a  to electric motor  191   a , such as belt drive, and the means is not limited to direct drive. Blower wheel  116   a  takes gas from oven cavity  102  and delivers the gas via gas transfer section  117   a  to the left top side of oven cavity  102 . Although illustrated as a conventional blower motor, blower motor shaft and blower wheel, other gas pumping means such as a compressor may be utilized to re-circulate gas to and from oven cavity  102  and applicant intends to encompass within the language any structure presently existing or developed in the future that performs the same function. Top left gas transfer section  117   a  is in fluid connection with a lower left gas transfer section  118   a  via a left vertical gas transfer section  119   a . Left vertical transfer section  119   a  is bounded by left side wall  105  and a left microwave waveguide section  120   a.    
         [0017]     As gas is discharged into top left gas transfer section  117   a , a selected portion of said gas is directed into a top left discharge section  121   a  by a top left deflecting means  122   a ,  FIG. 3  shown in the open position. Thereafter the gas is discharged through apertures located within a top left slotted or perforated discharge plate  123   a . Gas is then distributed into oven cavity  102 . Apertures  100   a  may be slotted, regularly formed or irregularly formed apertures and are illustrated herein as nozzles,  100   a  and  129   a , to be discussed herein, and applicant intends to encompass within the language any structure presently existing or developed in the future that performs the same function as  100   a ,  29   a  and to be discussed further herein  100   b  and  29   b . Gas is distributed through various apertures  100   a  located within left discharge plate  123   a  and delivered onto the left top and left side portions of the food product  110 . As gas enters top left gas delivery section  121   a , said gas may be further deflected via a top left gas deflecting means  124   a  as shown in  FIG. 3  in the open position. Gas deflecting means  124   a  is pivotally attached to gas discharge plate  123   a , although, other means for accomplishing said gas deflection may be utilized. For example means such as normally open, normally closed, or normally partially open and normally partially closed switched plates may be used (wherein said plates slide along the inside of perforated plate  123   a  to limit the aperture openings  100   a  of discharge plate  123   a ), and applicant intends to encompass within the language any structure presently existing or developed in the future that performs the same function. Gas that has not been discharged or deflected into top left gas delivery section  121   a  by gas deflecting means  122   a  flows to lower left gas transfer section  118   a  via vertical transfer section  119   a . Pivotally attached to waveguide section  120   a  is a lower gas transfer deflection mechanism  152   a ,  FIG. 3  that operates to limit the amount of gas that is transferred to lower gas transfer section  118   a . As used herein, the terms “flow control means” “gas deflecting means” “transfer deflection mechanism” and “flow control means” all have the same meaning and refer to means to control gas flow within the oven. Indeed, certain speed cooking operations may call for more gas flow to the lower part of the speed cooking oven, while other operations will call for little or no gas flow to the bottom side of the oven for delivery to the bottom of the food product. In those instances where little or no gas flow is desired upon the bottom surface of the food product, gas transfer deflection mechanism  152   a  may be closed in order to allow all, or substantially all, of the gas flow into top left gas delivery section  121   a.    
         [0018]     Gas that flows to lower left gas delivery section  118   a  may be re-heated, if required, by lower left heating means  126   a ,  FIG. 3 . After passing over heating elements  126   a , the gas may be further deflected by deflecting means  128   a ,  FIG. 3 , shown in the open position. As gas deflecting means  128   a  is rotated, directional control of the gas flow may be further refined, allowing for gas flow to pass through the upper or lower rows of apertures of lower gas plate  127   a  at various positions along food product  110  bottom surface,  FIG. 4   b . Although gas deflecting means  128   a  is shown as pivotally attached to left slotted or perforated gas discharge plate  127   a , gas deflecting means  128   a  is not limited to the pivotally attached means illustrated herein, and as described elsewhere herein, applicant intends to encompass within the language any structure presently existing or developed in the future that performs the same function. Apertures  100   a ,  100   b ,  129   a  and  129   b  are sized for low pressure drop, while providing and maintaining sufficient gas velocities of approximately 2000 ft/minute to approximately 7000 ft/minute to properly cook the food product, although velocities above 7000 ft/minute may be used and velocities less than 2000 ft/minute may also be utilized. As shown in  FIG. 4 , the apertures are adjusted such that the majority of the gas is supplied from the top left gas discharge section  121   a . The resulting imbalance of gas flows between the top left gas flow  130   a  and lower left gas flow  132   a  is desirable because the top flow  130   a  must aggressively remove moisture produced and escaping from the top surface, and top side surface of food product  110 . The imbalance also serves to heat, brown and/or heat and brown the food product  110 .  
         [0019]     Referring now to the right gas transfer system, gas is transferred to and from oven cavity  102  via a right gas transfer system, which is comprised of a right gas transfer section  115   b , which extends from the front to back of oven top wall  103 , along the right side of top wall  103 . In fluid connection with right gas transfer section  115   b  is top gas egress opening  112 , which is open to, and in fluid connection with oven cavity  102  through top wall  103 . Located within right gas transfer section  115   b  is right grease extractor  113   b . As gas is drawn through top gas egress opening  112 , the gas passes across right heating means  114   b , prior to entry in and through right grease extractor  113   b . After the gas is drawn across heating means  114   b  and through right grease extractor  113   b , it is then drawn through right odor filter  143   b  and into right gas transfer section  115   b . Alternate locations for right odor filters  143   a ,  143   b  can be utilized within the gas flow path and the location of the right odor filter adjacent to right grease extractor  113   b  is not required. In fluid connection with, and located within right gas transfer section  115   b  is a right gas accelerator, illustrated as right blower wheel  116   b . Connected to right blower wheel  116   b  is blower motor shaft  190   b , which is direct drive with electric motor  191   b . Blower wheel  116   b  takes gas from oven cavity  102  and delivers the gas via gas transfer section  117   b  to the right top side of oven cavity  102 . Top right gas transfer section  117   b  is in fluid connection with a lower right gas transfer section  118   b  via a right vertical gas transfer section  119   b . Right vertical transfer section  119   b  is bounded by right side wall  106  and a right microwave waveguide section  120   b.    
         [0020]     As gas is discharged into top right gas transfer section  117   b , a selected portion of said gas is directed into a top right discharge section  121   b  by a top right deflecting means  122   b , shown in the open position in  FIG. 4 . Thereafter the gas is discharged through a top right slotted or perforated discharge plate  123   b  into oven cavity  102 . Slotted or perforated right discharge plate  123   b  is used to distribute gas leaving top right gas delivery section  121   b  through various apertures  100   b  into oven cavity  102  and onto the right top and side portion of the food product  110 . As gas enters top right gas delivery section  121   b , said gas may be further deflected via a top right gas deflecting means  124   b  as shown in  FIG. 4 . As with  124   a , gas deflecting means  124   b  is shown as pivotally attached to slotted or perforated discharge plate  123   b , although other means for accomplishing said gas deflection may be utilized. Gas that has not been discharged or deflected into top right gas delivery section  121   b  by gas deflecting means  122   b  flows to lower right gas transfer section  118   b  via vertical transfer section  119   b . Pivotally attached to waveguide section  120   b  is a gas transfer deflection mechanism  152   b , shown in the open position,  FIG. 4 , that operates to limit the amount of gas that is transferred to lower gas transfer section  118   b . Again, as with the left side gas transfer system, certain speed cooking operations may call for more gas flow to the lower part of the speed cooking oven, while other operations will call for little or no gas flow to the lower part of the oven for bottom side browning of the food product. In those instances where little or no gas flow is desired upon the bottom surface of the food product, gas transfer deflection means  152   b  may be closed, or partially closed, in order to allow little or no gas flow to lower gas delivery section  118   b.    
         [0021]     Gas flow that that is distributed to lower right gas delivery section  118   b  may be re-heated, if required, by lower right heating means  126   b ,  FIG. 4 . After passing over heating elements  126   b , which may or may not be present in every oven, depending upon the particular oven requirements, the gas may be further deflected by deflecting means  128   b ,  FIG. 4 , shown in the open position. As gas deflecting means  128   b  is rotated, directional control of the gas flow may be further refined, allowing for gas flow to pass through the upper or lower apertures of lower gas plate  127   b  at various positions along food product  110  bottom surface. Apertures  100   b  and  129   b  are sized for low pressure drop, while providing and maintaining sufficient gas velocities of approximately 2000 ft/min to approximately 7000 ft./minute to properly cook the food product although as with other oven functions, gas flows above 7000 ft/minute and lower than 2000 ft/minute may be utilized as needed. Again, as shown in  FIG. 4 , the top apertures are adjusted such that the majority of the gas is supplied from the top right gas discharge section  121   b.    
         [0022]     As gas flow  130   a  is directed toward the center of oven cavity  102  from the left side and gas flow  130   b  is directed toward the center of oven cavity  102  from the right side, the gas flows meet upon the surface of the food product and turbulently mix, conflict and collide, thereby causing high heat transfer and rapid cooking of the food product. This turbulently mixed gas flow directed at the food product can best be described as glancing, conflicting and colliding gas flow patterns that spatially average the gas flow over the surface area of the food product producing high heat transfer and moisture removal rates at the food surface, thereby optimizing speed cooking. The gas flow is directed towards the top, the bottom and the sides of the food product from the left and right sides of the oven cavity and the left and right side gas flows conflict, collide and glance off each other at the food product surface before exiting the oven cavity through top gas egress opening. As used herein the term “mixing” refers to the glancing, conflicting and colliding gas flow patterns that meet at and upon the top surface, the bottom surface and the left and right side surfaces of the food product and produce high heat transfer and speed cooking of the food product due to spatial averaging of the gas flow heat transfer. As used herein, the terms “mix”, “mixing”, “turbulent mix” and “turbulent mixing”. The same mixing of gas flow occurs upon the lower surface and lower side surfaces of food product  110  by lower gas flows  132   a  and  132   b ,  FIG. 1 .  
         [0023]     In those instances wherein directional control of the gas flow is desired, gas deflecting means  122   a ,  122   b ,  124   a ,  124   b ,  128   a ,  128   b  and  152   a  and  152   b ,  FIG. 4   b  may be rotated such that gas flow is diverted to selected apertures, thereby effecting a different gas flow pattern and gas mixing upon the food product surface. Additionally, in those instances wherein no bottom side gas flow is desired, gas deflecting means  152   a ,  152   b  may be closed, thereby allowing for little or no passage of gas flow to the lower portion of the oven cavity. Various other adjustments of gas deflecting means  122   a ,  122   b ,  124   a ,  124   a ,  128   a ,  128   b ,  152   a ,  152   b  are possible and applicant intends to encompass within the language any structure presently existing or developed in the future that allows for combinations of open and closed positions by the various gas flow control means. Gas deflecting (flow control) means  122   a ,  122   b ,  124   a ,  124   b ,  128   a ,  128   b ,  152   a  and  152   b  may be manually controlled, automatically controlled via controller  134  or some combination of automatic and manual control and applicant intends to encompass within the language any structure presently existing or developed in the future that performs the function described herein concerning adjustment of the gas deflecting means.  
         [0024]     The gas flows within the oven, as well as other functions of cooking appliance are directed by controller  314 ,  FIG. 1 . Controller  134  determines, among other things, the velocity of gas flow, which may be constant or varied, or, may be constantly changed throughout the cooking cycle. It may be desired to cook the food product on one velocity throughout the entire cooking cycle, or to vary the gas velocity depending upon conditions such as a pre-determined cooking algorithm, or vary the velocity in response to various sensors that may be placed within the oven cavity, oven return air paths or various other positions within the oven. The location and placement of said sensors will be determined by the particular application of the oven. Additionally, other means may be utilized wherein data is transmitted back to controller  134 , and thereafter controller  134  adjusts the cooking in an appropriate manner. For example sensors (temperature, humidity, velocity, vision and airborne chemical mixture level sensors) may be utilized to constantly monitor the cooking conditions and adjust the gas flow accordingly within a cooking cycle, and other sensors not described herein may also be utilized. The speed cooking oven may utilize sensors that are not currently commercially utilized (such as laser, non-invasive temperature sensors and other sensors that are currently too expensive to be commercially feasible), and the speed cooking oven is not limited to those discussed herein, as many sensing devices are known and utilized in the cooking art.  
         [0025]     The most efficient utilization of the spent hot gas is by re-circulation of the gas flow through the oven cavity many times during a cooking cycle. During normal speed cooking it may be desirable for one food product to be cooked after another different type of food product (fish followed by pastry) with successive cycles continuing. For example shrimp may be cooked first, followed by a baked product or pastry. Without appropriate filtration, the odors from the shrimp will contaminate the baked product, producing an undesirable taste and odor in the pastry. There exists a need for further air clean-up (in addition to the grease extractors) to further scrub the gas flow of the particles that are not entrained by grease extractors  113   a  and  113   b . In instances wherein further filtration of the gas flow is desired, odor filters may be placed within the oven cavity.  FIG. 2  illustrates the use of odor filters  143   a  and  143   b  for this purpose. Left side odor filter  143   a  is attached within top left gas transfer section  117   a , downstream of left grease extractor  113   a  and right odor filter  143   b  is attached within right gas transfer section  117   b  downstream of right grease extractor  113   b . Odor filters  143   a  and  143   b  are attached in a manner that allows for their easy removal for cleaning and replacement. Gas that flows into the left and right gas transfer systems  115   a  and  115   b  first passes through odor filters  143   a  and  143   b . The gas flow is therefore further scrubbed after passage through grease extractors  113   a  and  13   b  in order to eliminate odors that could interfere with the proper taste of the food product currently being cooked. In some cases it may be beneficial to utilize a second set of odor filters, and these filters may be placed anywhere within the gas flow path of blower wheels  116   a  and  116   b . Odor filers  143   a , 143   b  may be catalytic type elements or other filtration means including, but not limited to activated charcoal, zeolite or ultra violet wavelight light. It is beneficial that the odor filters be comprised of a material, or materials, that effectively scrubs, or cleans the gas flow with a minimal amount of interference with the gas flow velocities. Additionally, it is beneficial that the odor filters be easily removed, easily cleaned and inexpensive for the operator to replace.  
         [0026]     During the cooking process it may be desirable to maintain oven cavity temperature at a constant level without the introduction of gas into oven cavity  102 . For example, the operator may be cooking a delicate pastry and may desire to finish food product  110  with no gas flow. This may be accomplished with a radiant only mode utilizing a gas by-pass system wherein gas flow is not allowed to enter oven cavity  102 , but is directed to a lower gas chamber  408 ,  FIG. 1  for by-pass circulation to and from heaters  114   a ,  114   b  via conduit  414 ,  FIG. 5 . In these instances appliance  101  may additionally include lower gas egress opening  410 , lower door  412 , conduit  414  and upper door  416  Lower gas egress opening  410  may be covered by lower door  412 ,  FIG. 2  or may be open as shown in  FIG. 1 .  
         [0027]     During the radiant cooking mode gas door  412  is opened and door  416  closed. And although doors  412  and  416  are graphically depicted as sliding doors,  FIGS. 1,2 , many methods may be employed to limit and allow gas to pass into conduit  414  and applicant intends to encompass within the language any structure presently existing or developed in the future that performs the same function as doors  412 ,  416 . With door  412  open and door  416  closed, gas flow is diverted around oven cavity  102  flowing into conduit  414  and discharged above heaters  114   a ,  114   b ,  FIG. 5 . Gas is then drawn through grease extractors  113   a ,  113   b  and odor filters  143   a ,  143   b , and into blower wheels  116   a ,  116   b  for return to conduits  11   a ,  117   b.    
         [0028]     Radiant mode allows the operator to maintain gas flow at a constant temperature, increase or decrease the temperature of the gas flow without affecting the food product currently being cooked. For example, an operator may currently cooking a food product at a selected temperature but desire to cook the next food product at a higher or lower temperature. In these instances, radiant mode may be utilized and gas flow partially or completely limited oven cavity  102 . The gas by-passes around oven cavity  102  but does not, or may not, directly impact the food product, thereby allowing the operator to increase or decrease the temperature of the gas flow and the temperature of the previously described cavity walls. In this manner, the operator gains additional flexibility.  
         [0029]     While the exemplary embodiments of the present invention have been shown and described, it will be understood that various changes and modifications to the foregoing embodiments may become apparent to those skilled in the art without departing from the spirit and scope of the present invention. Accordingly, the invention is not limited to the embodiments disclosed, but rather by the appended claims and their equivalents.