Patent Publication Number: US-2013239824-A1

Title: Tortilla conveying system for sequentially conveying a plurality of tortillas to be warmed

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a Divisional of co-pending U.S. patent application Ser. No. 13/019,780, filed on Feb. 2, 2011. 
    
    
     FIELD OF THE INVENTION 
     The invention relates generally to food preparation devices, and more specifically to tortilla warmers. 
     BACKGROUND OF THE INVENTION 
     Tortillas are a popular food item, usually enjoyed best when they have just been cooked. Uncooked tortillas typically do not provide the same taste appeal as warmed tortillas. Often, tortillas are eaten in combination with other hand-held food. Preparing such meals would require an added step beforehand, in order to warm the tortilla so as to optimize the tortilla&#39;s flavor and texture. 
     Heating devices, including devices designed specifically for heating tortillas, are known in the art. Tortilla warmers are popular for their ability to warm tortillas to an appropriate temperature so as to be properly enjoyed with a meal. However, current tortilla warmer equipment has significant drawbacks. Many tortilla warmers attempt to warm multiple tortillas as a batch, rather than one at a time in series. This does not ensure that all tortillas will be heated to the same degree, and can cause sticking among tortillas. 
     Other warmers that allow for heating of multiple tortillas require input of each tortilla into a separate compartment, which takes away from the convenience of a tortilla warmer. 
     Still other warmers that do warm tortillas in series nonetheless require insertion of one tortilla at a time, also detracting from the convenience to the user. 
     SUMMARY OF THE INVENTION 
     An improved tortilla conveying system, for sequentially conveying a plurality of tortillas to be warmed, is disclosed and claimed. The conveying system provides a stack of tortillas and automatically conveys tortillas sequentially through a tortilla warmer. The tortillas are stored in a container. A dragger at least frictionally engages the top side of the top tortilla, dragging the tortilla off of the top of the container for subsequent heating by a heating element of the tortilla warmer. 
     The tortilla container can automatically elevate the stack of tortillas, so a top tortilla always remains exposed at the top of the container. An extractor delivers the tortilla outside of the heating system once the tortilla is sufficiently warmed. The tortillas are warmed in sequence by a heating element, via conduction, convection, and/or radiation. In some embodiments, various components of the conveyer are synchronized, via a gearbox for example. 
     A general aspect of the invention is a tortilla conveying system of a tortilla warmer, for sequentially conveying a plurality of tortillas to be warmed. The tortilla conveying system includes: a container capable of holding a plurality of tortillas in a stacked configuration, with a top side of a top tortilla being exposed at a top of the container; and a dragger capable of at least frictionally engaging the top side of the top tortilla, and then dragging the top tortilla off of the top of the container for subsequent heating by a heating element of the tortilla warmer. 
     In some embodiments of the tortilla conveying system, the dragger includes a dragger head which makes direct contact with the top side of the top tortilla, so as to facilitate the at least frictional engagement with the top side of the top tortilla. In some of these embodiments, the dragger head is constrained to move horizontally within a track. 
     In some other embodiments including a dragger head, the dragger head includes a set of nails located on an underside of the dragger head. In some of these embodiments, the set of nails are arranged along a set of lines passing through a center of the underside of the dragger head. In some of these embodiments, the set of nails engage the top side of the top tortilla so as to create static friction between the set of nails and the top side of the top tortilla, depress the top side of the top tortilla, and/or pierce the top side of the top tortilla. In other embodiments including a set of nails, the set of nails are configured to create perforations in each tortilla, when it is the top tortilla. 
     In some embodiments, the dragger includes a dragger head mover, the dragger head mover moving the dragger head substantially laterally, so as to facilitate the dragging of the top tortilla. 
     In some embodiments, the dragger is driven by a rotating element that is pivotably connected to the dragger. In some of these embodiments, the rotating element is directly driven by a motor. In some embodiments, the container includes an elevator assembly for ensuring a top side of a top tortilla is constantly exposed at a top opening of the container. In some embodiments, the tortilla conveying system further includes a synchronizing control system for synchronizing movement of the elevator assembly and the dragger. 
     In some embodiments, the tortilla conveying system further includes at least one heating element. In some of these embodiments, the heating element is a conductive heating platform. In some embodiments, the tortilla warmer includes an extractor capable of delivering the top tortilla outside of the heating sub-system. In some embodiments, the tortilla conveying system further includes a lid for covering the top of the container when the at least one tortilla is not being warmed. 
     In some embodiments, heating of the top tortilla is performed by conduction, convection, and/or radiation. In some of these embodiments, conduction is produced by at least one heated roller. In some embodiments, radiation is produced by a resistive heating element, a microwave magnetron, or a carbon infrared emitter. 
     In some embodiments, the tortilla conveying system further comprises a housing to house the container and the dragger. In some of these embodiments, the housing further comprises a door which provides access to the container. 
     In another general aspect of the invention, a tortilla conveying system includes: a container capable of holding a plurality of tortillas in a stacked configuration, with a top side of a top tortilla being exposed at a top of the container; a dragger capable of at least frictionally engaging the top side of the top tortilla, and then dragging the top tortilla off of the top of the container for subsequent heating by a heating element of the tortilla warmer; a top heating platform, the top heating platform being capable of receiving the tortilla for heating by a heating element and rotating vertically so as to cause the top tortilla to slide off of the top heating platform; a slider adapted to guide the top tortilla sliding off of the top heating platform and to cause the top tortilla to land upside down onto a bottom heating platform; and a bottom heating platform, the bottom heating platform being capable of receiving the top tortilla in an upside-down configuration for further heating by a heating element, and delivering the top tortilla outside of the tortilla warmer. 
     In some embodiments, at the top heating platform and/or the bottom heating platform is a conductive heating element. 
     In some embodiments, the conveying system further includes a synchronizing control system for synchronizing movement of at least two of the following: the elevator assembly; the dragger; the top heating platform; and the bottom heating platform. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be more fully understood by reference to the detailed description, in conjunction with the following figures, wherein: 
         FIG. 1  is a profile view of the main elements of an embodiment of the tortilla warmer conveying system, with a dragger in a position to drag a top tortilla from a cartridge; 
         FIG. 2  is a profile view of the embodiment shown in  FIG. 1 , with the dragger dragging the top tortilla into a heating sub-system of the tortilla warmer; 
         FIG. 3  is a profile view of the embodiment shown in  FIG. 1 , with the dragger depositing the top tortilla onto a heating platform; 
         FIG. 4  is a profile view of the embodiment shown in  FIG. 1 , with the top tortilla fully positioned on the heating platform; 
         FIG. 5  is a profile view of the main elements of an alternative embodiment of the heating system, with a dragger in a position to drag a top tortilla from a cartridge; 
         FIG. 6  is a profile view of the embodiment shown in  FIG. 5 , with the dragger dragging the top tortilla towards a top heating element of the tortilla warmer; 
         FIG. 7  is a profile view of the embodiment shown in  FIG. 5 , with the dragger depositing the top tortilla onto the top heating element of the tortilla warmer; 
         FIG. 8  is a profile view of the embodiment shown in  FIG. 5 , with the top tortilla being rotated so as to be deposited onto a bottom heating element of the tortilla warmer; 
         FIG. 9A  is an isolated profile view of a nail dragger head; 
         FIG. 9B  is an isolated oblique underside view of the nail dragger head of  FIG. 5A ; 
         FIG. 10A  is an oblique view of a housing of the tortilla warmer, including a sliding access door for accessing a tortilla cartridge; 
         FIG. 10B  is the oblique view of  FIG. 6A , shown with the access door slid open to reveal the tortilla cartridge; 
         FIG. 10C  is the oblique view of  FIG. 6B , shown with the tortilla cartridge removed from the housing; 
         FIG. 11  is an exemplary control panel that can be located on the housing of the heating system; and 
         FIG. 12  is a flow chart showing the steps of heating in an exemplary embodiment of the heating system. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is a profile view of the main elements of an embodiment of the tortilla warmer conveying system, with a dragger in a position to drag a top tortilla from a cartridge. A container  100  is shown holding multiple tortillas  102  in a vertically stacked configuration. The container  100  of the embodiment shown is a tortilla cartridge which can be inserted into the tortilla warmer  101  via a handle  105 . A top tortilla  103  is exposed at its top surface. In some embodiments, the container  100  can include an elevator platform  104  for ensuring a top side of the top-most tortilla is always exposed at the top of the container, so as to be capable of being taken from the container  100 . The elevator platform  104  can be driven by a motor-driven elevator for example, such as an assembly including a motor-driven gear. 
     Also shown is a dragger  106  capable of at least frictionally engaging the top side of the top tortilla  103 , such as maintaining contact with the top tortilla  103  via static friction, and dragging the top tortilla  103  off the stack of tortillas  102  and out of the top of the container  100 . In the embodiment shown, the dragger  106  is constrained to move the top tortilla  103  substantially laterally, the substantial lateral movement being guided by a track  107  to which the dragger is connected. 
     In the embodiment shown, the dragger  106  is capable of dragging the top tortilla  103  out of the top of the container and into a heating sub-system  108  of the tortilla warmer  101 . In the embodiment shown, the dragger  106  is driven by a rotating element  109 , which can in turn be driven by another element such as a gear, for example. The rotating element  109  can cause oscillatory lateral movement of the dragger  106 . In the embodiment shown, the rotating element  109  rotates about a center point  110 , and a free hinge joint  111  connecting rotating element  109  and the dragger  106  traces a circular path as the rotating element  109  rotates. 
     In other embodiments, the dragger  106  can be moved in a different fashion, while still dragging the top tortilla  103  into the heating sub-system  108 . The dragger  106  can engage the top tortilla  103  via static friction, by depressing the top side of the top tortilla  103 , and/or by piercing the top side of the top tortilla  103 , for example. 
     Elements of the tortilla warmer conveying system disclosed herein can be controlled by electro-mechanical elements in some embodiments. Some such electro-mechanical elements can reside in a chamber  112  such as an electronics module and/or a gearbox. In some of these embodiments, a user-operable control panel  113 , in communication with elements resident within the chamber  112  for example, can reside on the housing  101  of the tortilla warmer, to facilitate controlling aspects of the conveying system, among potentially other aspects of the tortilla warmer  101 . 
       FIG. 2  is a profile view of the embodiment shown in  FIG. 1 , with the dragger dragging the top tortilla into a heating sub-system of the tortilla warmer. The dragger  106  is capable of at least frictionally engaging the top side of the top tortilla  103  of the stack of tortillas  102  and dragging the top tortilla away from the stack of tortillas  102  and into the heating sub-system  108 . The dragger  106  can repeat this action, thereby conveying a plurality of tortillas into the heating system, one at a time in sequence. 
     In the embodiment shown, the dragger  106  includes a dragger head  200  and a dragger arm  203 . The dragger head  200  makes direct contact with the top side of the top tortilla  103 , so as to facilitate the at least frictional engagement with the top side of the top tortilla  103 . The dragger arm  203  acts as a dragger head mover, moving the dragger head  200  substantially laterally, so as to facilitate the dragging of the top tortilla  103 . 
     The dragger head  200  is moved by the dragger arm  203 , which in turn is driven by a rotating element  109 . The rotating element  109  is rotated about a center point  110 , and is pivotably connected to the dragger  106  via a connection  111 . The dragger head  103  is driven in a substantially horizontal motion, guided by a horizontal guide track  204 . The dragger head  200  is moved rightwards, and then leftwards, as the rotating element  109  rotates one full revolution. 
     In the embodiment shown, the dragger head  200  includes a plurality of nails  204  which at least frictionally engage the tortilla and drag it into the heating sub-system  108 . The dragger head  200  can engage the top tortilla  103  through at least frictional engagement between the dragger head  200  and the top tortilla  103 . For example, in some embodiments the dragger head  200  includes a set of nails  204 . 
     In reference to the embodiment shown, the set of nails  204  can at least frictionally engage the top side of the top tortilla  103  in a variety of ways. For example, the set of nails  204  can press into the top side of the top tortilla, thereby creating static friction between the set of nails  204  and the top side of the top tortilla  103 . In other embodiments, the set of nails  204  can press into the top side of the top tortilla  103  so as to depress the top side of the top tortilla  103 , and thereby pull the top tortilla laterally  103  as the dragger head  204  moves laterally. In other embodiments, the set of nails  204  can pierce the top side of the top tortilla  103 , thereby further facilitating pulling of the top tortilla  103 . 
     In the embodiment shown, the dragger  106  is dragging the top tortilla  103  towards a heating platform  210 . In the embodiment shown, the top tortilla  103  is first dragged across a curved roller portion  206  before being deposited onto a heating platform  210 . 
     The heating system  108  can be any heating system known or appreciated by one of average skill in the art of heating tortillas and food-heating in general, and can employ heating via conduction, convection, and/or radiation, for example. For example, the heating system  108  can employ microwave heating, infrared heating, convection heating, conduction heating, and/or others, as well as a combination thereof. A heating element  208  is shown to represent a potential source of heat, such as a conductive toaster oven heating component providing heat to the volume enclosed by the boundaries of the heating system. Possible heating elements producing radiant heat can include a resistive a heating element, a microwave magnetron, and/or a carbon infrared emitter. 
       FIG. 3  is a profile view of the embodiment shown in  FIG. 1 , with the dragger  106  in the process of depositing the top tortilla  103  onto a heating platform  210 . The heating platform  210  can support the top tortilla  103  while the top tortilla  103  is heated within the heating sub-system  108 . A heating element  208  can contribute heat within the heating sub-system, so as to heat the top tortilla  103 . The heating element  208  can produce via conduction, convection, and/or radiation. Radiation can be produced by such heating elements  208  as a resistive heating element, a microwave magnetron, and/or a carbon infrared emitter, for example. 
       FIG. 4  is a profile view of the embodiment shown in  FIG. 1 , with the top tortilla  103  fully positioned on the heating platform  200 . The heating platform  200  can be configured to remain stationary during heating, or alternatively the heating platform  200  can be a roller that conveys the tortilla horizontally during the heating cycle (see  FIGS. 5-8 ). 
     After the top tortilla  103  has been sufficiently heated, the top tortilla  103  can be delivered outside of the heating sub-system by an extractor. In some of these embodiments, the extractor can deliver the top tortilla  103  outside of the tortilla warmer. In some embodiments, the heating platform  208  can facilitate such extracting of the top tortilla  103 , for example by dispensing the top tortilla  103  through a slot in the housing. In embodiments including a roller acting as a heating platform  208 , the roller can convey the top tortilla  103  through a slot. The roller can be powered to move in a manner that can accomplish such extracting of the top tortilla  103 , such as the roller rotating so as to enable the top tortilla  103  to roll downward off the roller and down a slide and through a slot, for example. In other embodiments, individual rolling sub-elements of a roller can be powered to roll simultaneously, so as to roll the top tortilla  103  through a slot. 
       FIG. 5  is a profile view of the main elements of an alternative embodiment of the heating system, with a dragger in a position to drag a top tortilla from a cartridge. A container  100  is shown holding multiple tortillas in a vertically stacked configuration  102 . A top tortilla  103  is exposed at the top of the stack of tortillas  102 . Also shown is a dragger  106  capable of at least frictionally engaging the top side of the top tortilla  103 , and dragging the top tortilla  103  out of the top of the container  100  and into a heating sub-system of the tortilla warmer. 
     A set of gears  500 ,  502 ,  504  are shown in this figure, the gears being capable of synchronizing the movement of two heated rollers (not shown in this figure). Synchronized movement can be executed via a gear box, for example. A slider  506  is adapted to guide the top tortilla  103  as it slides off of a top heating platform, so as to enable the top tortilla  103  to land upside down on a bottom heating platform. 
       FIG. 6  is a profile view of the embodiment shown in  FIG. 5 , with the dragger dragging the top tortilla towards a top heating element of the tortilla warmer. In this figure, a top heating element  600  and bottom heating platform  602  are shown. In the embodiment shown, both heating platforms  600 ,  602  are heated rollers, acting as conductive heating elements capable of heating the top tortilla  103  via conduction. 
     As shown in the figure, the dragger  106  drags the top tortilla  103  off of the stack of tortillas  102  and onto an introductory roller  206 , which facilitates the dragger  106  depositing the top tortilla  103  onto the top heating platform  600 . As the rotating element  109  rotates, it causes the dragger  106  and the top heating platform  600  to move in synchronized fashion, so that the top heating platform  600  is positioned out to receive the top tortilla  103  when the top tortilla  103  has been strategically placed so as to be received by the top heating platform  600 . Synchronized movement of the rotating element, the dragger, and/or the top heating platform can be executed via a gear box, for example. 
       FIG. 7  is a profile view of the embodiment shown in  FIG. 5 , with the dragger  106  depositing the top tortilla  103  onto the top heating element  600 , which is a conductive heating platform. In the embodiment shown, the top heating element  600  is a roller which can heat the bottom side of the top tortilla  103  via conduction. The top heating element  600  can also rotate, so as to deposit the top tortilla  103  upside-down onto a bottom heating element  602 , which is also a heating platform. The slider  506  facilitates the top tortilla  103  being deposited face-down onto the bottom heating element  602 . 
     The top heating element  600  is able to heat the bottom side of the top tortilla  103  once the top tortilla  103  is dragged onto the heating element  600 . In the embodiment shown, the top heating element  600  is capable of rotating vertically, so as to deposit the top tortilla  103  when the top heating element  600  has sufficiently rotated. A bottom heating element  602  is also shown underneath the top heating element  600 . A slider  506 , which is adapted to guide the top tortilla  103  sliding off of the top heating element  600  and to cause the top tortilla to land upside down onto the bottom heating element  602 , is also shown. A synchronized control system can synchronize the movement of the dragger  106 , the top heating element  600 , and the bottom heating element  602 . Synchronized movement of the rotating element, the dragger, the top heating platform and/or the bottom heating element can be executed via a gear box, for example. The heating elements  600 ,  602  can be electrically powered and can warm the designated side of the top tortilla  103  via conduction, for example. 
       FIG. 8  is a profile view of the embodiment shown in  FIG. 5 , with the top tortilla being rotated so as to be deposited onto a bottom heating element of the tortilla warmer. 
     A slider oriented vertically in the shape of an arc  506  can stabilize the tortilla  103  while it is being rotated, and being deposited onto the bottom heating element  602 . The bottom heating element  602  is also an electrically heated roller, in the embodiment shown. The bottom heating element can also serve as an extractor for delivering the tortilla  103  outside of the tortilla warmer, upon completion of heating the tortilla. 
     All of the moving components of the conveying system and/or the heating system, or a sub-combination thereof, can be electrically powered. Furthermore, components of the conveying system can be synchronized so as to automatically be timed to interact with each other at the appropriate speed and timing. For example, a gear controlling a cycle of movement of the dragger  500  can be in communication with a gear controlling a cycle of rotation of the roller  504  (via middle gear  502 ), as shown. 
       FIG. 9A  is an isolated profile view of a dragger head  200 . In the embodiment shown, the dragger head  200  includes nails  204  that are capable of can at least frictionally engaging a surface of a tortilla. A connector bracket  900  is also shown at the top of the dragger head  200 , which is able to connect the dragger head  200  to the dragger arm (shown in earlier drawings). The connector bracket  900  can also serve as a connection point between the dragger head  200  and the track (shown in earlier drawings), so as to facilitate substantially lateral movement of the dragger head  200 . The dragger head  200  includes a structural support  901  that promotes stability of the nails  204 . The nails  204  can engage a tortilla via static friction, via depression of the tortilla, or even piercing of a surface of the tortilla. In preferred embodiments, the nails  204  can be configured to wholly or partially retract during a certain portion of the cycle of movement, so as to facilitate disengagement from a tortilla when the tortilla is dragged to a heating platform and needs to separate from the dragger head. Such retraction can be accomplished via a spring system, for example. 
       FIG. 9B  is an isolated oblique underside view of the nail dragger of  FIG. 5A , shown in relation to a tortilla with which it can at least frictionally engage. As shown in this figure, the nails  204  can be arranged in a pattern of several lines intersecting with each other at their respective middle points. The nails  204  can be configured so as to penetrate a tortilla, thereby impressing this same pattern of lines in the tortilla itself. This pattern can facilitate breaking a sufficiently heated and hardened tortilla into wedges, which is sometimes desirable when eating tostadas, for example. In the embodiment shown, this dragger head  200  includes a solid lip  901 . 
       FIG. 10A  is an oblique view of a housing  101  of the tortilla warmer, including a sliding access door  1004  for accessing a tortilla cartridge (the handle  105  of the cartridge is visible protruding from an inlet of the access door  1004 ), and  FIG. 10B  is the oblique view of  FIG. 6A , shown with the access door (not shown here) slid open to reveal the tortilla cartridge  100 .  FIG. 10C  is the oblique view of  FIG. 6B , shown with the tortilla cartridge  100  having been removed from the housing  101 . The tortilla cartridge  100  can be stored in a separate place, such as a refrigerator, when not being used to provide tortillas for a heating session of the tortilla warmer. 
       FIG. 11  is an exemplary control panel  113  that can be located on the housing  101  of the tortilla warmer. Up and down arrow buttons  1100 ,  1102  can enable a user to adjust the desired texture of a heated tortilla. Changing the desired texture can change the temperature of the heating sub-system, for example. The up  1100  and down  1102  arrows can also enable a user to adjust the desired speed at which the tortillas are conveyed through the heating subsystem in sequence. A display screen  113  can display what setting is being input for a given option. 
       FIG. 12  is a flow chart showing the steps of heating in an exemplary embodiment of the heating system, this particular embodiment including a top heating element and a bottom heating element. First, a stack of tortillas are inserted into the tortilla cartridge container  1200 . Next, the dragger drags the top tortilla towards the top heating element, as the top heating element rotates close to the level horizontal position so as to receive the top tortilla  1202 . 
     Once the top tortilla has been deposited onto the top heating element, its bottom side is warmed by the top heating roller  1204 . As the top heating element continues rotating, it eventually reaches an angle which enables the top tortilla to be deposited upside-down onto the bottom heating element  1206 . The bottom heating element then heats the top side of the top tortilla  1208 . 
     Finally the tortilla is expelled from the tortilla warmer housing via an exit slot and is ready to be eaten  1210 . In some embodiments, a cover used for the tortilla cartridge when tortillas are not being warmed, can be placed under the exit slot when tortillas are being heated, so as to receive the heated tortillas. 
     A tortilla warmer equipped with the conveying system disclosed herein, can further include an electrical power cord, a smoke detector, a fire alarm, and/or an emergency off switch. 
     Other modifications and implementations will occur to those skilled in the art without departing from the spirit and the scope of the invention as claimed. Accordingly, the above description is not intended to limit the invention except as indicated in the following claims.