Abstract:
A grilling appliance is disclosed for preparing various different types of food wherein the food is conveyed through the appliance, from a food insert end of the appliance to a food removal end of the appliance, by means of continuously movable flow-through upper and lower cooperating conveyors operatively associated with platen-type heating members over which the upper and lower conveyors are conveyed so as to be heated by the platen-type heating members and thereby, in turn, heat, brown, or carmelize the food as desired or required.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This patent application is a non-provisional patent application conversion of U.S. Provisional Patent Application Ser. No. 62/240,553 which was filed on Oct. 13, 2015, the priority benefits of which are hereby claimed. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates generally to food preparation apparatus, equipment, or appliances, and more particularly to a grilling appliance for preparing various different types of food wherein the food is conveyed through the appliance, from a food insert end of the appliance to a food removal end of the appliance, by means of continuously movable flow-through upper and lower cooperating conveyors operatively associated with platen-type heating members over which the upper and lower conveyors are conveyed so as to be heated by the platen-type heating members and thereby, in turn, heat, brown, or carmelize the food as desired or required. 
       BACKGROUND OF THE INVENTION 
       [0003]    In the food preparation industry, particularly within the fast-food industry, various types of apparatus, equipment, or appliances are utilized to cook or prepare various different types of food such as, for example, burritos, Panini sandwiches, crunch wraps, and the like. The apparatus, equipment, or appliances that are conventionally employed are either flat grills which effectively cook or toast one side of the food, and then they cook or toast the other side of the food when the food is flipped or turned over onto its other side upon the flat grill. Alternatively, clam-shell apparatus or appliances have also been employed which can effectively cook or toast both sides of the food simultaneously as a result of the food being placed upon a lower food support cooking platform or grill when the clamshell apparatus is disposed at its open position, and then the clamshell apparatus is pivotally moved to its closed position so as to bring the upper food cooking grill portion into contact with the food. The operational drawback or disadvantage of such apparatus, equipment, or appliances, however, is the fact that the cooking time is effectively monitored and necessarily controlled by means of the personnel doing the grilling or cooking, with the result that sometimes, the food is undercooked, overcooked, or even burned, neither one of which operations and resulting conditions produces a satisfactory and tasty end food product. 
         [0004]    A need therefore exists in the art for a new and improved grilling appliance for cooking food wherein the aforenoted disadvantages or operational drawbacks characteristic of conventional cooking apparatus, equipment, or appliances are effectively overcome or eliminated. More particularly, a need exists in the art for a new and improved grilling appliance wherein the cooking process or procedure is effectively controlled in such a manner that the food being cooked or prepared cannot be undercooked, overcooked, or burned. Still more particularly, a need exists in the art for a new and improved grilling appliance wherein the entire cooking procedure or process is automatically controlled from the beginning of the cooking cycle to the end of the cooking cycle and is predeterminedly controlled in light of the particular food product that is being cooked or re-thermalized. 
       Overall Objectives of the Invention 
       [0005]    The overall objectives of the present invention are to provide a new and improved grilling appliance for cooking food which will overcome and eliminate the various disadvantages and drawbacks characteristic of conventional grilling apparatus, equipment, or appliances for cooking food, to provide a new and improved grilling appliance for cooking food which will effectively overcome and eliminate the poor cooking results often encountered with conventional grilling appliances, apparatus, or equipment for cooking food, to provide a new and improved grilling appliance which will enhance the efficiency of the food-cooking procedure or process, and to provide a new and improved grilling appliance which will automatically control the food-cooking procedure or process, from the beginning of the food-cooking cycle to the end of the food cooking cycle, so as to provide a properly cooked or re-thermalized and tasty end food product. 
       SUMMARY OF THE INVENTION 
       [0006]    The foregoing and other objectives are achieved in accordance with the teachings and principles of the present invention through the provision of a new and improved grilling appliance for cooking food wherein the grilling appliance comprises upper and lower endless conveyor belts which are routed over and around upper and lower heated platens and which are fabricated, for example, from PTFE, polytetrafluoroethylene, which are adapted to be disposed in contact with the food articles being cooked, and yet the food articles will not adhere or stick to the conveyor belts. The conveyor belts are flow-through conveyor belts, that is, they extend from a first food-insert end of the appliance toward a second oppositely disposed food-output end of the appliance, and consequently, depending upon the speed of the conveyor belts, which can be optimally controlled, the time during which the food articles are exposed to the heated conveyor belts, which are heated by means of the heated platens, is predetermined such that the food articles are not in fact undercooked or overcooked but are properly cooked so as to result in a very satisfactorily cooked and tasty end food product. It is further noted that the disposition of the upper platen, around which the upper conveyor belt is routed, can be adjusted with respect to the lower platen and the lower conveyor belt so as to effectively adjust the gap defined between the upper and lower platens and the upper and lower conveyor belts. In this manner, the grilling appliance can accommodate different foods having different height dimensions such as, for example, burritos, Panini sandwiches, crunch wraps, and the like. Still further, the appliance provides for the easy removal of the conveyor belts for cleaning, maintenance, or exchange of the belts. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    Various other features and attendant advantages of the present invention will be more fully appreciated from the following detailed description when considered in connection with the accompanying drawings in which like reference characters designate like or corresponding parts throughout the several views, and wherein: 
           [0008]      FIG. 1  is a schematic front-side perspective view of the new and improved conveyor type grilling machine as constructed in accordance with the teachings and principles of the present invention and showing the various component parts thereof; 
           [0009]      FIG. 2  is a schematic side elevational view of the new and improved conveyor type grilling machine as illustrated within  FIG. 1 ; 
           [0010]      FIG. 3  is a top plan view of the new and improved conveyor-type grilling machine as illustrated within  FIGS. 1 and 2 ; 
           [0011]      FIG. 4  is a schematic front-side perspective view of the new and improved conveyor type grilling machine, similar to that of  FIG. 1 , showing, however, the entry end and exit end doors of the grilling machine in their opened positions so as to facilitate, for example, maintenance, cleaning, and conveyor belt exchange operations which may need to be performed upon the appliance at predetermined times; 
           [0012]      FIG. 5  is a partial perspective view of the new and improved conveyor type grilling machine as illustrated within  FIGS. 1-4  showing the provision of, for example, a portion of the lower endless conveyor belt assembly, comprising the lower heated platen and tensioned idler roller, over and around which the lower conveyor belt is conducted so as to be heated by means of the lower heated platen; 
           [0013]      FIG. 6  is a plan view of an embodiment of a uniquely constructed endless conveyor belt, which may be used as an upper conveyor belt, a lower conveyor belt, or as both conveyor belts, whereby either one or both of the upper and/or lower surface portions of the cooked food product will effectively have grill lines formed thereon so as to simulate grill lines that would otherwise appear upon such food products if the food products were actually cooked, for example, upon a charcoal grill; 
           [0014]      FIG. 7  is a perspective plan view showing the installation of a food holding tray which may be fixedly secured upon the exit end of the grilling machine so as to effectively catch and hold the food products which have been cooked and which have been discharged from the grilling machine by means of the lower endless conveyor belt; 
           [0015]      FIG. 8  is a schematic front-side perspective view of the grilling appliance showing the internal components, comprising a rack and pinion drive mechanism, of the grilling compliance, which permits the upper endless conveyor belt and its operatively associated heated platen to have its elevational position, relative to the lower endless conveyor belt and its operatively associated heated platen, to be vertically adjusted so as to permit the grilling appliance to be utilized to cook different foods have different height or thickness dimensions, and wherein a circle area A is noted; 
           [0016]      FIG. 8A  is an enlarged view of the circled area denoted A illustrated in  FIG. 10  illustrating the details of the rack and pinion drive mechanism, the pilot pin locator plate having a multitude of pilot pin locator holes defined therein, and the pilot pin located upon the distal end of a pivotally or arcuately movable arm fixedly connected to the pinion of the rack and pinion drive mechanism, whereby the upper conveyor belt and its operatively associated heated platen are disposed at their lowest position relative to the lower conveyor belt and its operatively associated heated platen; 
           [0017]      FIG. 9  is a schematic front-side perspective view of the grilling appliance, similar to that of  FIG. 8 , showing, however, the internal components, comprising the rack and pinion drive mechanism, of the grilling compliance, which permits the upper endless conveyor belt and its operatively associated heated platen to have its elevational position, relative to the lower endless conveyor belt and its operatively associated heated platen, to be vertically adjusted so as to permit the grilling appliance to be utilized to cook different foods have different height or thickness dimensions, and wherein a circle area B is noted; and 
           [0018]      FIG. 9B  an enlarged view of the circled area denoted B illustrated in  FIG. 9  showing the details of the rack and pinion drive mechanism, the pilot pin locator plate having a multitude of pilot pin locator holes defined therein, and the pilot pin located upon the distal end of a pivotally or arcuately movable arm fixedly connected to the pinion of the rack and pinion drive mechanism, whereby the upper conveyor belt and its operatively associated heated platen are disposed at their highest position relative to the lower conveyor belt and its operatively associated heated platen; 
           [0019]      FIG. 10  is a schematic front-side perspective view of the grilling appliance with a side housing wall portion of the appliance illustrated as having been removed such that access can be gained to the internal components of the appliance in order to achieve a lower conveyor belt exchange operation; 
           [0020]      FIG. 11A  is a schematic front-side perspective view of the grilling appliance with a side housing wall portion of the appliance illustrated as having been removed such that access can be gained to the internal components of the appliance in order to achieve an upper conveyor belt exchange operation; 
           [0021]      FIG. 11B  is a schematic front-side perspective view of the grilling appliance, similar to that of  FIG. 11A , wherein the side housing wall portion of the appliance illustrated has been removed such that access can be gained to the internal components of the appliance in order to achieve an upper conveyor belt exchange operation, and wherein the front access door has been moved to its open position, and the pair of pivot links, connecting the rack of the height adjustment mechanism for the upper conveyor belt to the upper conveyor belt mounting system, have been moved to their out-of-the way position so as to permit removal of the upper conveyor belt side cover so as to, in turn, permit access to and removal of the upper conveyor belt; and 
           [0022]      FIG. 11C  is a schematic front-side perspective view of the grilling appliance, similar to that of  FIGS. 11A and 11B , wherein, as a result of the removal of the upper conveyor belt side cover, the upper conveyor belt can in fact be removed. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0023]    Referring now to the drawings, and more particularly to  FIGS. 1-5  thereof, a new and improved conveyor-type grilling appliance for cooking or re-thermalizing food is disclosed and is generally indicated by the reference character  100 . More particularly, it is seen that the new and improved conveyor-type grilling appliance  100  comprises a housing  102  within which a pair upper and lower conveyor belts  104 ,  106  are disposed as can best be appreciated from  FIGS. 1,3 , and  4 . The upper and lower conveyor belts  104 , 106  are endless conveyor belts that flow through the housing  102  from a food product input or entrance end  108  of the housing  102  to a food product output or exit/discharge end  110  of the housing  102 . The upper conveyor belt  104  is wholly enclosed within the housing  102 , while the opposite ends of the lower conveyor belt  106  extend beyond each end of the housing  102 . In this manner, a first movable platform region  112  of the lower conveyor belt  106  is defined at the food product input or entrance end  108  of the housing  102  for permitting food-cooking personnel to effectively place the food, to be cooked, onto the input platform region  112  of the lower conveyor belt  106  whereby the lower conveyor belt  106  will then move the food, to be cooked, into the appliance  100 . Once the food, to be cooked, is inside the appliance  100 , the food, to be cooked, will effectively be captured between the upper and lower conveyor belts  104 , 106  and will be propelled forwardly by the upper and lower conveyor belts  104 ,  106  until the food exits from the oppositely disposed exit or discharge end  110  of the appliance housing  102 . The oppositely disposed exit or discharge end  110  of the lower conveyor belt  106 , disposed at the exit or discharge region of the appliance  100 , effectively forms a second movable platform region  114  from which food cooking personnel can re-move the cooked food. Alternatively, as disclosed within  FIG. 7 , a suitable tray  116  can be fixedly attached to the housing  102  at the exit or discharge end  110  of the appliance  100  for effectively catching and holding the cooked food  118  as the cooked food is discharged and deposited into the tray  116  by means of the mov-able lower conveyor belt  106 . 
         [0024]    With reference being made to  FIG. 5 , there is disclosed a partial perspective view of, for example, a portion of the lower endless conveyor belt support and drive assembly  118  which is seen to comprise, for example, a lower heated platen  120  fixedly mounted upon a platen platform  121  and a tensioned front idler roller  122  over and around which the lower endless conveyor belt  106 , not shown, is conducted so as to be heated by means of the lower heated platen  120 . A rear drive roller, not shown, is also provided, and both the upper and lower endless conveyor belts  104 , 106  are fabricated, for example, from polytetrafluoroethylene (PTFE) such that the upper and lower endless conveyor belts  104 , 106 , which are adapted to be disposed in contact with the food articles being cooked as a result of the upper and lower endless conveyor belts  104 , 106  propelling the food to be cooked or re-thermalized through the appliance  100  from the food input or entrance end  108  of the housing  102  to the food output or exit/discharge end  110  of the housing  102 , will effectively prevent the food products being cooked from adhering or sticking to the upper and lower endless conveyor belts  104 , 106 . The drive system, not shown, for the rear drive roller can of course be any suitable conventional drive system, such as, for example, a suitable chain and sprocket drive assembly. It is to be further noted that a user interface or similar control panel  124  is provided upon a side wall portion of the housing  102 , as can best be seen in  FIGS. 1,2, and 4 , in this manner, the temperature of both the upper and lower heated platens, exemplified by means of the lower heated platen  120 , as well as the speed of the upper and lower endless conveyor belts  104 , 106 , which are driven at the same synchronous speed, can be optimally controlled so as to in turn control the real time during which the food articles are exposed to the upper and lower endless conveyor belts  104 , 106  heated by means of the heated platens exemplified by means of the lower heated platen  120 . In this manner, the actual or real cooking time is effectively predetermined such that the food articles are not in fact undercooked or overcooked but are properly cooked or re-thermalized so as to result in a very satisfactorily cooked or re-thermalized and tasty end food product. 
         [0025]    With reference being made to  FIG. 6 , there is disclosed a uniquely fabricated conveyor belt which may be used either as the upper endless conveyor belt  104 , the endless lower conveyor belt  106 , or as both the upper and lower endless conveyor belts  104 , 106 . As has been noted, the endless conveyor belt  104  or  106  is fabricated from polytetrafluoroethylene (PTFE), however, in accordance with the unique fabrication techniques employed in fabricating the endless conveyor belt  104  or  106 , it is seen that the endless conveyor belt  104  or  106  comprises a first base endless conveyor belt  104  or  106  fabricated from a first polytetrafluoroethylene (PTFE) component  126 , upon top of which a second polytetrafluoroethylene (PTFE) component  128 , comprising a plurality of transversely spaced strips, is fixedly secured. Accordingly, those regions of the composite endless conveyor belt  104  or  106 , which have the transversely spaced strips defining the second polytetrafluoroethylene (PTFE)  128  fixedly secured thereon, will effectively have a larger thickness dimension than those regions of the composite endless conveyor belt  104  or  106  which do not have the transversely spaced strips defining the second polyte-trafluoroethylene (PTFE)  128  fixedly secured thereon. Accordingly, as the food articles are conveyed through the appliance housing  102  by means of the operatively cooperative upper and lower endless conveyor belts  104 , 106 , the transversely spaced strips comprising the second polytetrafluoroethylene (PTFE)  128  will effectively be forced into contact with the external surface portions of the food articles being conveyed through the appliance  102 , to a greater degree than that of the base endless conveyor belt portion  126 , so as to effectively form visual stripes upon the external surface portions of the food articles which simulate grill marks or lines that would appear upon the food articles as if the food articles had actually been cooked or prepared upon, for example, a charcoal grill. 
         [0026]    It is lastly noted that the disposition of the upper platen, around which the upper conveyor belt is routed, can be adjusted with respect to the lower platen and the lower conveyor belt so as to effectively adjust the gap defined between the upper and lower platens and the upper and lower endless conveyor belts. In this manner, the grilling appliance can accommodate different foods having different height or thickness dimensions such as, for example, burritos, Panini sandwiches, crunch wraps, and the like. Still further, the appliance provides for the easy removal of the upper and lower endless conveyor belts  104 , 106  for cleaning, maintenance, or exchange of the conveyor belts  104 , 106  as may be needed or required. With reference therefore being made to  FIGS. 8,8A,9, and 9B , the vertical adjustment of the upper heated platen and the upper endless conveyor belt  104  that is disposed therearound, with respect to the lower heated platen and the lower endless conveyor belt  106  disposed therearound, will be discussed first. It is to be noted that while the vertical adjustment of the upper heated platen and the upper endless conveyor belt  104 , with respect to the lower heated platen and the lower endless conveyor belt  106  can be achieved by various means, including the use of, for example, hydraulic, pneumatic, or electrical actuators, a manual adjustment system has been incorporated within the conveyor-type grilling appliance  100  of the present invention. As disclosed within  FIGS. 8,8A,9, and 9B , both sides of the convey-ortype grilling appliance housing  102  are provided with a manual adjustment pilot pin  130  which is fixedly secured to a first distal end of a pilot pin mounting arm  132 , while the second opposite proximal end of the pilot pin mounting arm  132  is fixedly connected to the axial center of a circular disk-type pinion  134 , it being noted that only one adjustment system comprising one pilot pin  130 , one pilot pin mounting arm  132 , and one circular disk-type pinion  134  is illustrated in these side perspective views. These components can likewise be seen in  FIGS. 1,2, and 4 , it being noted that the side wall of the appliance housing  102  is to be considered transparent for visual purposes of this disclosure so as to effectively see, for example, the mounting arm  132  which is disposed internally of the appliance housing  102 . 
         [0027]    In addition to the aforenoted components, a rack  136 , having gear teeth  138  formed upon an upper arcuate edge portion thereof, is provided for engagement with gear teeth  140  formed upon the outer circumferential peripheral surface of the pinion  134 , the rack  136  and pinion  134  assembly being biased toward their uppermost position by spring-biasing means, not shown. Still further, a pilot pin locator plate  142  is provided with a multitude of pilot pin locator holes  144  which are defined within an arcuate array covering an angular extent of approximately 45° extending from a leftmost or western position upon the pilot pin locator plate  142  to a lowermost or southern position upon the pilot pin locator plate  142 . The pilot pin  130  is a spring-biased pull-pin that is capable of being moved in a direction along the axis around which the pilot pin  130  is defined. The pilot pin  130  is thus pulled axially outwardly so as to effectively be disengaged from one of the pilot pin locator holes  144  defined within the pilot pin locator plate  142  whereby the pilot pin  130  can then be moved toward another pilot pin locator hole  144  defined within the pilot pin locator plate  142 , and is permitted to be moved axially inwardly under the biasing force of its biasing spring, not shown, so as to permit the locking pin  130  to be inserted into another or different pilot pin locator hole  144  in order to effectively lock the upper heated platen and the upper endless conveyor belt  104  at a particular vertical position with respect to the lower heated platen and the lower endless conveyor belt  106  when the vertical adjustment of the upper heated platen and the upper endless conveyor belt  104  relative to the lower heated platen and the lower endless conveyor belt  106  is to be achieved. 
         [0028]    Each pilot locator hole  144  permits the upper heated platen and the upper endless conveyor belt  104  to be moved one quarter of an inch (0.25″), vertically upwardly or vertically downwardly, with respect to the lower heated platen and the lower endless conveyor belt  106 . As disclosed within  FIGS. 8 and 8A , it is seen that the upper heated platen and the upper endless conveyor belt  104  are disposed at their lowermost position with respect to the lower heated platen and the lower endless conveyor belt  106  as a result of the pilot pin mounting arm  132  extending horizontally to the left and the pilot pin  130  being disposed within the uppermost and leftmost pilot pin locator hole  144  of the arcuate array of pilot pin locator holes  144  defined within the pilot pin locator plate  142 , whereas, as disclosed within  FIGS. 9 and 9B , it is seen that the upper heated platen and the upper endless conveyor belt  104  are disposed at their uppermost position with respect to the lower heated platen and the lower endless conveyor belt  106  as a result of the pilot pin mounting arm  132  extending substantially vertically downwardly whereby the pilot pin  130  is disposed within the lowermost or southernmost pilot pin locator hole  144  of the arcuate array of pilot pin locator holes  144  defined within the pilot pin locator plate  142 . It is to be lastly noted that an arcuate slot, not shown, must be provided within a portion of each external side wall  146  of the housing  102  so as to permit the pilot pin  130  to project through the side wall  146  of the housing  102  and yet travel or be moved through its arcuate path when the pilot pin  130  is being moved from one pilot pin locator hole  144  to another pilot pin locator hole  144  in order to vertically adjust the disposition of the upper heated platen and the upper endless conveyor belt  104  with respect to the lower heated platen and the lower endless conveyor belt  106 . In addition, a linkage plate  148 , having a substantially triangular configuration, is connected at one corner thereof to the rack  136  while another corner thereof is operatively connected to the drive chain, not shown, which is operatively associated with the upper conveyor belt drive roller. The linkage plate  148  is seen to move, as can be appreciated with reference being made to  FIGS. 8,9, and 9B , as the vertical adjustment of the upper heated platen and the upper endless conveyor belt  104 , with respect to the lower heated platen and the lower endless conveyor belt  106 , is achieved in order to effectively eliminate any slack in the drive chain operatively associated with the upper conveyor belt drive roller. 
         [0029]    Lastly, with reference being made to  FIGS. 10 and 11A-11C , the removal of the upper and lower endless conveyor belts  104 , 106 , for cleaning, maintenance, or exchange of the conveyor belts  104 , 106  as may be needed or required, will now be discussed. With reference first being made to  FIG. 10 , the removal and exchange of the lower conveyor belt  106  will be discussed first. In order to remove and exchange the lower conveyor belt  106 , one of the external side walls  146  of the housing  102  is initially removed so as to provide access to the inner components of the appliance  100 . A lower door  150  of the housing  102 , operatively associated with and covering the lower conveyor belt idler roller  152 , is then initially moved from its closed position to its opened position so as to in fact provide access to the lower conveyor belt idler roller  152 . The lower conveyor belt idler roller  152 , which may be similar to conveyor belt idler roller  122 , is spring-biased by means of a suitable tensioning spring, not shown, whereby the lower conveyor belt  106  will remain properly tensioned about the lower conveyor belt drive roller, not shown, and the lower conveyor belt idler roller  152 . In addition, an idler roller lock mechanism  154 , which is mounted upon an interior side wall portion of the appliance  100 , is pivotally moved from its upper position, at which it is effectively disposed within a slot  156  which can best be seen in  FIG. 10 , to a pivotally lower position at which the idler roller lock mechanism  154  is removed from the slot  156 . Accordingly, the lower conveyor belt idler roller  152  may now be moved inwardly toward the internal part of the housing  102  and against the biasing force of its biasing spring, not shown, in view of the fact that the idler roller lock mechanism  154  has effectively been moved from a position at which it blocks the internal movement of the lower conveyor belt idler roller  152  to a position at which it no longer blocks the internal movement of the lower conveyor belt idler roller  152 . Therefore, the tension imposed upon the lower conveyor belt  106  by means of the spring-biased lower conveyor belt idler roller  152  has effectively been relieved, whereby the lower conveyor belt  106  can then be removed from its disposition overlying the lower conveyor belt drive and idler rollers as well as the lower heated platen. 
         [0030]    With reference lastly being made to  FIGS. 11A-11C , the removal and exchange of the upper conveyor belt  104  will now be discussed. Once again, one of the side walls  146  of the appliance is initially removed so as to permit personnel to gain access to the interior components of the appliance. The rack and pinion assemblies  136 , 134  have been moved to and locked at their uppermost positions. It is seen that each one of the rack and pinion assemblies  136 , 134  are operatively connected to each side of the upper conveyor belt heated platen platform, which may be similar to the heated platen platform  121 , by means of two linkage members  158 , 158  which can best be seen in  FIG. 10 . Each side set of linkage members  158 , 158  is pivotally attached or mounted at relatively central portions thereof to an interior sidewall portion  160  of the appliance  100  as at  162 . Upper end portions of the linkage members  158 , 158  are pivotally connected to the rack  134  by means of a first set of pull-pins  164 , 164  which can best be seen in  FIG. 10 , while lower end portions of the linkage members  158 , 158  are pivotally connected to the upper heated platen platform, not shown, by means of a second set of pull-pins  166 , 166 , as can also best be seen in  FIG. 10 . Accordingly, the next step in the procedure to be conducted in connection with the removal and exchange of the upper conveyor belt  104  is the removal of the first and second sets of pull-pins  164 ,  166  so as to permit the opposite end portions of the linkage members  158 , 158  to be disconnected from the rack  134  and the upper heated platen platform, not illustrated. The linkage members  158 , 158  can then be moved to horizontally oriented positions, as shown in  FIG. 11A , at which positions the linkage members  158 ,  158  no longer overlie an upper conveyor belt side cover panel  168 . 
         [0031]    Accordingly, the upper conveyor belt side cover panel  168  can now be removed from the interior side wall portion  160  of the appliance as shown in  FIG. 11B  after suitable fasteners, not shown, are removed which have effectively connected the upper conveyor belt side cover panel  168  to the interior side wall portion  160  of the appliance  100 . As can also best be seen in  FIG. 11B , the upper conveyor belt side cover panel  168  has a pair of arcuate slots  170 , 170  formed therein for permitting the second set of pull pins  166 , 166 , attached to the lower end portions of the linkage members  158 , 158 , to traverse such slots  170 , 170  as the rack and pinion assembly  136 , 134  serves to alter or adjust the vertical disposition of the upper heated platen and the upper conveyor belt  104  relative to the lower heated platen and the lower conveyor belt  106 . Once the foregoing procedures have been accomplished, the front or rear access door  172  of the appliance, which is pivotally connected to and operatively associated with that end of the appliance  100  at which the upper conveyor belt idler roller  174 , as shown in  FIG. 11C , is positioned, is moved to and locked at its opened position. Access is now gained with respect to the upper conveyor belt  104  and its idler roller  174 . As was the case with the removal or exchange operation previously noted in connection with the lower conveyor belt  106 , the upper conveyor belt idler roller  174  may now be moved inwardly toward the internal part of the housing  102  and against the biasing force of its biasing spring, not shown. Therefore, the tension imposed upon the upper conveyor belt  104  by means of the spring-biased up-per conveyor belt idler roller  174  has effectively been relieved, whereby the upper conveyor belt  104  can then be removed from its disposition overlying the upper conveyor belt drive and idler rollers as well as the upper heated platen. 
         [0032]    Obviously, many variations and modifications of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the present invention may be practiced otherwise than as specifically described herein. 
       KEY TO REFERENCE NUMBERS IN THE DRAWINGS 
       [0000]    
       
           100 —Conveyor type grilling appliance 
           102 —Housing of  100   
           104 —Upper endless conveyor belt 
           106 —Lower endless conveyor belt 
           108 —Food product input/entrance end of housing  102   
           110 —Food product output or exit/discharge end of housing  102   
           112 —First movable platform region of lower conveyor belt  106   
           114 —Second movable platform region of lower conveyor belt  106   
           116 —Food product discharge tray at food product discharge end of  102   
           118 —Lower endless conveyor belt sup-port and drive assembly  118   
           120 —Lower heated platen 
           121 —Platen platform 
           122 —Lower front tensioned conveyor belt idler roller 
           124 —User interface/control panel upon side wall portion of housing  102   
           126 —First base polytetrafluoroethylene (PTFE) component 
           128 —Second polytetrafluoroethylene (PTFE) sealed atop  126   
           130 —Adjustment pilot pin 
           132 —Pilot pin mounting arm 
           134 —Pinion of upper platen/conveyor belt adjustment system 
           136 —Rack of upper platen/conveyor belt adjustment system 
           138 —Gear teeth of rack  136   
           140 —Gear teeth of pinion  134   
           142 —Pilot pin locator plate 
           144 —Pilot pin locator holes defined within pilot pin locator plate  142   
           146 —Side wall of housing  102   
           148 —Linkage plate 
           150 —Lower door of housing  102   
           152 —Lower front tensioned conveyor belt idler roller 
           154 —Idler roller lock mechanism 
           156 —Slot for accommodating idler roller lock mechanism in its up position 
           158 —Linkage members connecting the rack/pinion to upper heated platen 
           160 —Interior side wall of appliance  100   
           162 —Pivotal attachment of linkages  158  to  160   
           164 —First set of pull-pins connecting linkage members  158  to rack  136   
           166 —Second set of pull-pins connecting linkage members  158  to upper platen 
           168 —Upper conveyor belt side cover panel 
           170 —Arcuate slots within side cover panel  168   
           172 —Access door of appliance  100   
           174 —Upper conveyor belt idler roller