Patent Publication Number: US-11389028-B2

Title: Oil filtration system and method for automated fryer

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional application of and claims the benefit of U.S. patent application Ser. No. 15/945,350, filed Apr. 4, 2018, which claimed the benefit of U.S. Provisional Patent Application Ser. No. 62/482,902, filed Apr. 7, 2017 (expired), the disclosures of which are incorporated by reference herein in their entireties. 
    
    
     TECHNICAL FIELD 
     This application relates generally to food product cooking systems and methods. More specifically, this application describes mechanisms and methods for adding space and time efficiencies in food production environments such as restaurants. 
     BACKGROUND 
     Cooking devices, such as fryers, are used to cook various food products, e.g., poultry, fish, potato products, and the like. Such cooking devices may include one or more cooking chambers, e.g., fryer pots or vats, which may be filled with a cooking medium, e.g., an oil, a liquid shortening, or a meltable-solid shortening. Such cooking apparatuses also may include a heating element, e.g., an electrical heating element, such as a heating coil, or a gas heating element, such as a gas burner and gas conveying tubes, which heat the cooking medium in the cooking chamber. After the cooking medium reaches a preset cooking temperature, the food products are placed into the cooking medium such that the food products are cooked in the cooking medium. For example, the food products may be positioned inside a container, e.g., a wire basket, and submerged in the cooking medium for a predetermined amount of time sufficient to cook the food products. 
     In some designs, the container may be automatically conveyed through the cooking chamber along a movement path in the oil to reduce the amount of involvement required by restaurant employees for properly cooking the food products and/or to cook multiple containers of food products in a continuous cycle. In this regard, for high volume productions, such as those typical in a fast food restaurant environment, a number of containers may be continuously conveyed in a carousel-like fashion. Such high volume fryers are typically relatively large to accommodate the full extent of the movement path of the containers through the cooking chamber. In particular, these fryers typically have a large footprint and thus occupy a large amount of floor space, leaving limited space for additional fryers, other equipment, storage, employees, etc. For example, some fryers of this type have a footprint of approximately 72 inches wide×36 inches deep×72 inches tall. The space allotted to the fryer may also be vertically bounded by a corresponding hood, such as an exhaust or vent hood, positioned thereover. Thus, the benefits of such fryers may be outweighed by the amount of horizontal and/or vertical space which they require. 
     Moreover, the quality of the oil in the cooking chamber must be maintained at a desired level of purity to extend the useful life of the oil. Typical oil filtration systems require a dedicated oil filtration cycle, wherein container conveyance and food product cooking are interrupted while the oil is treated. For example, the oil may be completely or partially drained from the cooking chamber during this process such that insufficient oil is present in the cooking chamber for proper cooking of the food products. The filtration cycle may also require the heating element to be shut off for safety reasons. Once the oil filtration cycle is complete, normal operation may resume until the next oil filtration cycle. The intermittent interruptions caused by the oil filtration cycles necessarily results in undesirable delays and decreased production. 
     Thus, it would be desirable to provide systems and methods to cook food product in a more efficient manner, specifically with regard to time and space considerations. 
     SUMMARY 
     In one embodiment, a fryer includes a cooking chamber for holding a cooking medium and at least one heating element positioned within the cooking chamber. The fryer also includes a chain conveyor for selectively advancing at least one basket configured to contain food product through the cooking chamber along a movement path defining a continuous loop, the chain conveyor including first and second chains coupled together by the at least one basket extending therebetween. The movement path includes a series of legs such that the at least one basket moves substantially vertically from above the cooking medium to a greatest depth within the cooking medium and subsequently moves substantially horizontally at the greatest depth within the cooking medium. 
     In another embodiment, a fryer includes a cooking chamber for holding a cooking medium and at least one heating element positioned within the cooking chamber. The fryer also includes a conveyor for selectively advancing at least one basket configured to contain food product through the cooking chamber along a movement path, the basket including a lid portion hingedly coupled to a bottom portion such that the lid portion is pivotable relative to the bottom portion between an opened position and a closed position. The fryer further includes a lid rail catch bar configured to engage the lid portion of the basket and a bottom rail catch bar configured to engage the bottom portion of the basket. Engagement between the lid rail catch bar and the lid portion and engagement between the bottom rail catch bar and the bottom portion during advancement of the conveyor cause the lid portion to pivot relative to the bottom portion toward the opened position for dispensing food product from the basket. 
     In yet another embodiment an oil filtration system for a fryer includes a housing defining an interior space and including an inlet for supplying unfiltered oil to the interior space and an outlet for dispensing filtered oil from the interior space, the unfiltered oil containing particles of debris collected from food products during operation of the fryer. The oil filtration system also includes a conveyor belt positioned in the interior space for receiving the unfiltered oil from the inlet and for advancing at least a portion of the unfiltered oil through the interior space, the conveyor belt formed from material that allows passage of oil without particles towards the outlet. The oil filtration system further includes a scraper positioned in the interior space, wherein at least a portion of the scraper contacts the conveyor belt to inhibit the advancement of particles within the oil on the conveyor belt, thereby converting the unfiltered oil into filtered oil before flow towards the outlet. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various additional features and advantages of the invention will become more apparent to those of ordinary skill in the art upon review of the following detailed description of one or more illustrative embodiments taken in conjunction with the accompanying drawings. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate one or more embodiments of the invention and, together with the general description given above and the detailed description given below, serve to explain the one or more embodiments of the invention. 
         FIG. 1  is a perspective view of an exemplary fryer in accordance with one embodiment of the invention. 
         FIG. 2  is a front elevation view of the fryer of  FIG. 1 . 
         FIG. 3  is a left side elevation view of the fryer of  FIG. 1 . 
         FIG. 4A  is a perspective view of the basket shown in  FIG. 1  showing the basket in a closed position. 
         FIG. 4B  is a perspective view similar to  FIG. 4A  showing the basket in an opened position. 
         FIG. 5  is a partial cross sectional side view of the fryer of  FIG. 1 , taken along line  5 - 5  in  FIG. 1 , and showing the movement path of the baskets. 
         FIGS. 6A-6E  are partial cross sectional side views similar to  FIG. 5 , magnified to show a series of steps in the automatic opening and closing of a basket by the lid rail catch bar and bottom rail catch bar. 
         FIG. 7  is a cross sectional side view of the oil filtration system shown in  FIG. 1 , taken along line  7 - 7  in  FIG. 1 , and showing the continuous filtration of the oil by the belt and scraper of the oil filter. 
     
    
    
     DETAILED DESCRIPTION 
     With reference to  FIGS. 1-7 , an automated cooking apparatus such as a fryer  10  is shown in accordance with one embodiment. As set forth in further detail below, the fryer  10  provides improved efficiency in cooking operations. For example, the fryer  10  is capable of cooking a high volume of food products in a relatively small space. In one embodiment, the fryer  10  may cook approximately 240 pounds of boneless chicken patties per hour. Thus, the fryer  10  may cook twice as much food product as a typical 2-well fryer occupying the same footprint, which would only cook approximately 120 pounds of boneless chicken patties per hour. The fryer  10  is also capable of filtering oil while continuously cooking food products to maintain uninterrupted production and avoid delays associated with dedicated oil filtration cycles. The features of the fryer  10  are set forth in further detail below to clarify each of these functional advantages and other benefits provided in this disclosure. 
     As shown in  FIGS. 1-3 , the fryer  10  is of a generally upright or vertically oriented configuration, and includes a main housing  12 , a chain driving assembly  14 , and a continuous oil filtration system  16 . The main housing includes a frame  20  mounted on a plurality of wheels  22  so that the fryer  10  may be easily moveable on a surface such as a floor. In one embodiment, one or more of the wheels  22  may be lockable to prevent unwanted movement of the fryer  10  during operation. Alternatively, the wheels  22  may be eliminated in other embodiments without departing from the scope of the invention. 
     Upper and lower wall panels  30 ,  32  and/or first and second doors  34 ,  36  are provided on the frame  20  to cover various interior portions of the main housing  12 . The doors  34 ,  36  may provide access to components or other items contained within the main housing  12 , and some or all of the wall panels  30 ,  32  may be removable for this purpose. As shown, the lower wall panels  32  include vents  38  for allowing heat within the main housing  12  to escape. A table top  40  is mounted on top of the frame  20  and may be used to support food products, containers, utensils, or other items. For example, a user, such as a restaurant employee, may place containers of uncooked and/or cooked food products on the table top  40  during a food preparation process. A control panel  42  mounted on the second door  36  provides a human-machine interface configured to receive commands from a user, such as a restaurant employee, and may display information regarding a status of the fryer  10 . It will be appreciated that various modifications may be made to the wall panels  30 ,  32 , doors  34 ,  36 , table top  40 , and/or control panel  42  without departing from the scope of the invention. In any event, the main housing  12  houses a fryer manifold  48  and a chain conveyor  50  for selectively advancing food product through a cooking chamber  52  ( FIG. 5 ) of the fryer manifold  48 , as discussed in greater detail below. 
     Referring now to  FIGS. 4A and 4B , with continued reference to  FIGS. 1-3 , the chain conveyor  50  includes first and second chains  60 ,  62 . More particularly, each of the chains  60 ,  62  is a roller chain and includes a series of inner links  64 , outer links  66 , rollers  68 , and pins  70 , and each of the inner and outer links includes two apertures  72 ,  74  sized and spaced apart to receive the pins  70 , as is known. The pins  70  may be secured within the apertures  72 ,  74  via a friction fit and/or via a spring clip  76 . 
     As shown, the first and second chains  60 ,  62  are spaced apart and coupled together by a plurality of baskets  80 . Each basket  80  includes a lid portion  82  coupled to a bottom portion  84 . Together, the lid portion  82  and bottom portion  84  define an interior space  86  of the basket  80 . As shown, the lid portion  82  is coupled to the bottom portion  84  via a number of hinges or hooks  88 , as discussed in greater detail below. In this manner, the lid portion  82  and bottom portion  84  are pivotable relative to each other about the hinges  88  between a closed position ( FIG. 4A ) restricting access to the interior space  86  and securing the contents of the basket  80 , and an opened position ( FIG. 4B ) providing access to the interior space  86  for loading and/or unloading food. In one embodiment, the interior space  86  may be sized to accommodate a small batch of food. For example, the interior space  86  may be sized to accommodate approximately four 4 oz. breaded boneless chicken breast patties. In addition or alternatively, the basket  80  may be biased toward the closed position. For example, the hinges  88  may be spring hinges. 
     Each basket  80  defines a cage-like construction. In this regard, the bottom portion  84  includes first and second solid side panels  90 ,  92  coupled together by a plurality of elongate members extending therebetween. The side panels  90 ,  92  provide side barriers to the basket  80 . In the embodiment shown, the elongate members include a leading lower elongate member  100 , a middle lower elongate member  102 , a trailing lower elongate member  104 , and a trailing upper elongate member  106 . A catch member  101  ( FIG. 4B ) is positioned forward of the leading lower elongate member  100 . The bottom portion  84  further includes a number of elongate cross-members  108  extending at least between the leading lower and trailing lower elongate members  100 ,  104  and generally perpendicular thereto such that the bottom portion  84  has a generally webbed configuration (with openings that are sized to allow oil flow into and out of the interior space  86 , but not escape of food products when in the closed position) and provides a bottom barrier to the basket  80 . In the embodiment shown, the elongate cross-members  108  extend beyond the trailing lower elongate member  104  and are curved upwardly toward the trailing upper elongate member  106  to provide a rear barrier to the basket  80 . It will be appreciated that various other configurations of the bottom portion  84  may be used, as may be desired. For example, the solid side panels  90 ,  92  may be replaced by side panels having a webbed configuration. In any event, the elongate members  100 ,  102 ,  104 ,  106  and/or cross-members  108  are spaced apart to allow the free passage of oil therebetween while inhibiting the passage of food product therebetween, and are constructed of a material having sufficient strength and durability to support food product carried in the basket  80 . For example, the elongate members  100 ,  102 ,  104 ,  106  may be metal wires having a diameter of between approximately 0.091 inch and approximately 0.243 inch. In addition or alternatively, the elongate cross-members  108  may be metal wires having a diameter of between approximately 0.062 inch and approximately 0.177 inch. 
     The lid portion  82  includes a plurality of elongate members  110 ,  112 ,  114 ,  116  generally similar to the elongate members  100 ,  102 ,  104 ,  106  of the bottom portion  84 . In the embodiment shown, the elongate members include a leading upper elongate member  110 , a middle upper elongate member  112 , a trailing upper elongate member  114 , and a leading lower elongate member  116 . The lid portion  82  further includes a number of elongate cross-members  118  extending at least between the leading upper and trailing upper elongate members  110 ,  114  and generally perpendicular thereto such that the lid portion  82  has a generally webbed configuration (with openings sized similar to those described above) and provides a top barrier to the basket  80 . In the embodiment shown, three of the elongate cross-members  118  terminate at the hooks  88 , which are positioned over the trailing upper elongate member  106  of the bottom portion  84  to pivotably couple the lid portion  82  to the bottom portion  84 . Also in the embodiment shown, the leading upper elongate member  110  is of a length greater than the distance between the first and second side panels  90 ,  92  of the bottom portion  84  such that abutment between the distal ends of the leading upper elongate member  110  and the first and second side panels  90 ,  92  limits rotation of the lid portion  82  relative to the bottom portion  84  to the desired closed position. In the embodiment shown, the elongate cross-members  118  extend beyond the leading upper elongate member  110  and are curved downwardly toward the leading lower elongate member  116  to provide a front barrier to the basket  80  in the closed position. It will be appreciated that various other configurations of the lid portion  82  may be used, as may be desired. In any event, the elongate members  110 ,  112 ,  114 ,  116  and/or cross-members  118  are spaced apart to allow the free passage of oil therebetween while inhibiting the passage of food product therebetween, and are constructed of a material having sufficient strength and durability to suppress buoyant food product carried in the basket  80 . For example, the elongate members  110 ,  112 ,  114 ,  116  may be metal wires having a diameter of between approximately 0.091 inch and approximately 0.243 inch. In addition or alternatively, the elongate cross-members  118  may be metal wires having a diameter of between approximately 0.062 inch and approximately 0.177 inch. 
     In the embodiment shown, the first and second side panels  90 ,  92  are attached to the first and second chains  60 ,  62 , respectively. In particular, each of the side panels  90 ,  92  includes a sleeve  120  sized and shaped to receive a projection  122  extending from the respective chain  60 ,  62 . For example, the projection  122  may be an extension of a pin  70  of the chain  60 ,  62 , in one embodiment. In addition or alternatively one or both of the sleeve  120  and projection  122  may be welded to the respective side panel  90 ,  92 . In this manner, the bottom portion  84 , and consequently the basket  80 , are pivotable relative to the chains  60 ,  62  about the sleeves  120  and/or projections  122 . The sleeves  120  are each positioned approximately halfway along the width of the respective side panel  90 ,  92  to promote proper balancing of the baskets  80  and avoid accidental pivoting of the bottom portion  84  relative to the chains  60 ,  62  during operation. It will be appreciated that the basket  80  may be pivotably attached to the chains  60 ,  62  in other manners without departing from the scope of the invention. 
     With specific reference now to  FIG. 5 , an interior space of the fryer manifold  48  defines, at least in part, the cooking chamber  52  through which the chain conveyor  50 , and thus the baskets  80 , are advanced. Nine baskets  80  are shown on the illustrated chain conveyor  50  for the sake of simplicity of illustration. However, any number of baskets  80  may be provided as may be desired. In one exemplary embodiment, the fryer  10  may accommodate thirty-two baskets  80  along the entire movement path of the chains  60 ,  62 . For example, the baskets  80  may be arranged immediately one after another along the chains  60 ,  62 . 
     As shown, the cooking chamber  52  is generally C-shaped, having a generally horizontal upper portion  130 , a generally vertical middle portion  132 , and a generally horizontal lower portion  134 . A cover plate  136  mounted over the fryer manifold  48  partially covers the upper portion  130 . A supply of oil  140  or any other suitable cooking medium is provided to the cooking chamber  52  to at least partially fill the middle and/or lower portions  132 ,  134  thereof. Thus, the portions of the cooking chamber  52  filled with oil  140  may be collectively referred to as the oil vat of the fryer  10 . A number of heating elements  142  are positioned in at least the lower portion  134  of the cooking chamber  52  for heating the oil  140  so as to cook food products submerged therein. In the embodiment shown, two heating elements  142  are positioned in the lower portion  134  of the cooking chamber  52 . However, the cooking chamber  52  may include any number of heating elements  142  in any arrangement, as may be desired. As is known, electricity or gas may be selectively supplied to the heating elements  142 , and sumps (not shown) may be provided at lowermost portions of the cooking chamber  52  to allow oil drainage therefrom. 
     As shown, the chain conveyor  50  is positioned over a plurality of rollers in a continuous loop through the fryer  10 . More particularly, the first chain  60  is positioned over six idler pulleys  150 ,  152 ,  154 ,  156 ,  158 ,  160  arranged at various locations in the fryer  10 , and is further positioned over a driven sprocket gear  162  in the upper portion  130  of the cooking chamber  52 . While the idler pulleys  150 ,  152 ,  154 ,  156 ,  158 ,  160  are illustrated as wheels, it will be appreciated that any or all of the idler pulleys  150 ,  152 ,  154 ,  156 ,  158 ,  160  may be sprocket gears. Though not shown in detail, the second chain  62  is positioned over seven idler pulleys arranged at locations corresponding to the six idler pulleys  150 ,  152 ,  154 ,  156 ,  158 ,  160  and the driven sprocket gear  162 , such that the first chain  60  may be considered a driven chain while the second chain  62  may be considered an idler chain. In this regard, the driven sprocket gear  162  engages with the first chain  60  so that rotating the driven sprocket gear  162  drives the chain conveyor  50  along a movement path, as discussed in further detail below. 
     In the embodiment shown, the first idler pulleys  150  are positioned substantially external of the cooking chamber  52  while the remaining rollers  152 ,  154 ,  156 ,  158 ,  160 ,  162  are positioned within the various portions of the cooking chamber  52 . To this end, pulley supports  170 ,  172  are coupled to and extend from the fryer manifold  48  to provide mounting locations for the first idler pulleys  150 . Portions of the pulley supports  170 ,  172  extend over and conceal the first idler pulleys  150  and adjacent portions of the chains  60 ,  62 . It will be appreciated that the illustrated arrangement is exemplary only and various other arrangements of the various rollers  150 ,  152 ,  154 ,  156 ,  158 ,  160 ,  162  may be used. For example, the locations of the driven sprocket gear  162  and one of the idler pulleys  150 ,  152 ,  154 ,  156 ,  158 ,  160  may be switched. In addition or alternatively, the fryer  10  may be equipped with an additional driven sprocket gear and the first and second chains  60 ,  62  may be positioned over respective driven sprocket gears, such that each of the chains  60 ,  62  may be considered to be driven chains. 
     The chain driving assembly  14  includes a motor  180  ( FIGS. 1-3 ) mounted to the cover plate  136  for supplying rotary motion to drive the chain conveyor  50 . For example, the motor  180  may include a motor sprocket gear (not shown) which rotates when the motor  180  is activated. The motor sprocket gear may, in turn, engage with a drive chain (not shown) operably coupled to a drive shaft  182 . The drive shaft  182  is coupled to the driven sprocket gear  162  so as to transmit the motion from the motor  180  and/or motor sprocket gear to the driven sprocket gear  162  to drive the chain conveyor  50 . It will be appreciated that the output rate of the motor  180  and/or the gearing between the motor  180  and the driven sprocket gear  162  correspond to the speed of the chain conveyor  50 , which impacts the cooking time of food product in the cooking chamber  52 . Thus, these factors may be varied depending on a desired cooking time. In the embodiment shown, a drive chain guard  184  ( FIGS. 1-3 ) is positioned over at least part of the chain driving assembly  14  to conceal the drive chain and/or other components of the chain driving assembly  14 . 
     The movement path of the chain conveyor  50 , and thus the baskets  80 , is illustrated by the arrows A 1 . While various directional terms such as “left” and “right” are used herein to describe this path, these terms are used only with respect to the exemplary frame of reference shown in  FIG. 5  and are not intended to be limiting. In the embodiment shown, the loop formed by the chain conveyor  50 , and thus the movement path, is generally C-shaped. More particularly, each chain  60 ,  62  is positioned over a total of seven rollers in the upper, middle, and lower portions  130 ,  132 ,  134  of the cooking chamber  52  such that the movement path may be generally defined by seven legs. 
     Initially in the first leg, each basket  80  moves rightward in a generally horizontal manner from the first idler pulleys  150  toward the driven sprocket gear  162  (and corresponding idler pulley with regard to the second chain  62 ) and into the upper portion  130  of the cooking chamber  52 . Prior to entering the cooking chamber  52 , the basket  80  may be accessible to a user, such as a restaurant employee, who may manually pivot the lid portion  82  with respect to the bottom portion  84  and/or pivot the bottom portion  84  with respect to the chains  60 ,  62  in order to access the interior space  86  of the basket  80  and load uncooked food product therein. Thus, this portion of the first leg may be referred to as a loading zone of the fryer  10 . The user may subsequently return the basket  80  to the closed position. In addition or alternatively, the baskets  80  may be automatically opened and loaded with uncooked food product, such that the fryer  10  may be considered self-loading. In any event, once closed, the biasing of the basket  80  toward the closed position may prevent the bottom portion  84  from pivoting downwardly to open the basket  80  under the weight of the food product, and the central positioning of the sleeves  120  on the first and second side panels  90 ,  92  of the bottom portion  84  may assist the basket  80  in maintaining a generally horizontal orientation. 
     As the basket  80  reaches the end of the first leg, the basket  80  orbits or rotates about the driven sprocket gear  162  into the second leg. During this rotation and others, the pivotable relationship between the basket  80  and the chains  60 ,  62  allows the basket  80  to maintain its generally horizontal orientation. In the second leg, each basket  80  moves generally vertically downward into the middle portion  132  of the cooking chamber  52  and toward the oil  140  and second idler pulley  152 . As the basket  80  is submerged into the oil  140 , any food product contained in the basket  80  may begin to cook. The biasing of the basket  80  toward the closed position may prevent the lid portion  82  from pivoting upwardly to open the basket  80  under the buoyancy of the food product in the oil  140 . The basket  80  continues along the second leg into the lower portion  134  of the cooking chamber  52  and to its greatest depth within the oil  140 , and rotates about the second idler pulley  152  into the third leg. 
     In the third leg, each basket  80  moves leftward in a generally horizontal manner at the greatest depth within the oil  140  and in the lower portion  134  of the cooking chamber  52  under the heating elements  142  and toward the third idler pulley  154 . As the basket  80  reaches the end of the third leg, the basket  80  rotates about the third idler pulley  154  into the fourth leg, which is at a higher location that is lesser in depth within the oil  140  as compared to the third leg. In the fourth leg, each basket  80  moves rightward in a generally horizontal manner in the lower portion  134  of the cooking chamber  52  over the heating elements  142  and toward the fourth idler pulley  156 . When the basket  80  reaches the end of the fourth leg, the basket  80  rotates about the fourth idler pulley  156  into the fifth leg. In the fifth leg, each basket  80  moves generally vertically upward into the middle portion  132  of the cooking chamber  52  toward the fifth idler pulley  158  and out of the oil  140 . As the basket  80  emerges from the oil  140 , any residual oil on the cooked food product may pass through the bottom portion  84  of the basket  80  and drain back into the oil vat. 
     When the basket  80  reaches the end of the fifth leg, the basket  80  rotates about the fifth idler pulley  158  into the sixth leg. In the sixth leg, the basket  80  moves at an incline in a generally upward and leftward manner over a hopper  190  into the upper portion  130  of the cooking chamber  52  and toward the sixth idler pulley  160 . As shown, the incline of the sixth leg is relatively gentle to provide proper unloading of cooked food products, as discussed in greater detail below. For example, this incline may be defined by an angle α of between approximately 10 degrees and approximately 30 degrees with respect to horizontal. In one embodiment, the incline may be defined by an angle α of approximately 20 degrees with respect to horizontal. Unlike the previous legs and transitions between legs, the sixth leg and/or transition from the fifth leg into the sixth leg are configured to reorient and/or open the basket  80 . 
     In this regard, and with reference to  FIGS. 6A-6E , a lid rail catch bar  200  and a bottom rail catch bar  202  are provided proximate to the sixth leg. More particularly, the lid rail catch bar  200  extends along substantially the entire length of the sixth leg and parallel thereto. Thus, the lid rail catch bar  200  may also be oriented relative to horizontal by about the angle α. As shown, the lid rail catch bar  200  is mounted to the fryer manifold  48  via brackets  204  and fasteners  206 . The lid rail catch bar  200  includes a cam surface  208  and a top surface  210  which are configured to engage with the leading upper elongate member  110  of the lid portion  82  ( FIG. 6A ) during the transition of the basket  80  into the sixth leg, such that the leading upper elongate member  110  may ride along the lid rail catch bar  200  during the sixth leg. 
     The bottom rail catch bar  202  is mounted to the fryer manifold  48  via a fastener  212  and includes an abutment surface  214  and an inclined top surface  216 . In the embodiment shown, the inclined top surface  216  is parallel to the lid rail catch bar  200  and the sixth leg, and thus may also be oriented relative to horizontal by about the angle α. The abutment surface  214  is configured to avoid interfering with the advancement of the lid portion  82  and to abut the catch member  101  (and/or the leading lower elongate member  100  of the bottom portion  84  and/or the distal ends of the elongate cross-members  108 ) ( FIG. 6B ) during the transition of the basket  80  into the sixth leg, such that forward progress of the bottom portion  84  is temporarily halted and/or slowed while the chains  60 ,  62  continue to advance. As a result, the bottom portion  84  is forced against the bias toward the closed position (if present) to pivot counterclockwise relative to the chains  60 ,  62  about the sleeves  120  and/or projections  122  toward a near vertical orientation ( FIG. 6C ). The lid rail catch bar  200  prevents the lid portion  82  from pivoting along with the bottom portion  84 , and consequently causes the basket  80  to open as the chains  60 ,  62  continue to advance along the sixth leg. 
     With the bottom portion  84  in a near-vertical orientation and the basket  80  opened, any food product contained in the basket  80  may slide along the bottom portion  84  and automatically dispense into the hopper  190 . To this end, an unloading ramp  220  may be provided between the abutment surface  214  of the bottom rail catch bar  202  and the hopper  190  for directing food product from the bottom portion  84  into the hopper  190 . The elongate cross-members  108  of the bottom portion may promote sliding of the food product as a result of their being oriented substantially parallel to the direction in which the food slides. In this regard, the elongate members  100 ,  102 ,  104 ,  106  of the bottom portion  84 , which are perpendicular to the sliding direction, are on the undersides of the elongate cross-members  108  so as to avoid having joints between the members  100 ,  102 ,  104 ,  106  and cross-members  108  positioned in the flow path of food product, which could interfere with the free sliding of the food product along the elongate cross-members  108  when the basket is to be emptied at the sixth leg of movement. As the basket  80  continues its travel leftwards and upwards following the movement path, the catch member  101  follows the path on the bottom rail catch bar  202  from the abutment surface  214  to the inclined top surface  216  ( FIG. 6D ). Because the inclined top surface  216  is parallel to the movement path, the basket  80  remains in the open position as long as the catch member  101  and the inclined top surface  216  remain in contact with each other. 
     During this period, any remaining food product may be dispensed from the bottom portion  84  to the hopper  190 . Thus, the fryer  10  may be considered a self-unloading fryer, and the portions of the sixth leg wherein the basket  80  is opened and the bottom portion  84  is oriented toward vertical for unloading may be collectively referred to as an unloading zone of the fryer  10 . When the catch member  101  clears the bottom rail catch bar  202 , the biasing of the basket  80  toward the closed position causes the lid portion  82  and bottom portion  84  to pivot relative to each other to return the basket  80  to the closed position, and the central positioning of the sleeves  120  on the first and second side panels  90 ,  92  of the bottom portion  84  urges the basket  80  to return to a generally horizontal orientation ( FIG. 6E ). Alternatively, if the basket  80  is not biased toward the closed position, the bottom portion  84  may return to a generally horizontal orientation while the lid portion  82  may remain pivoted relative to the bottom portion  84  such that the basket  80  remains in an open position. 
     As the basket  80  reaches the end of the sixth leg, the basket  80  orbits or rotates about the sixth idler pulley  160  into the seventh leg while maintaining a generally horizontal orientation as previously described. In the seventh leg, each basket  80  moves leftward in a generally horizontal manner toward the first idler pulley  150 . During this period, the basket  80  travels over a basket guard  230  mounted to the fryer manifold  48 . When the basket  80  reaches the end of the seventh leg, the basket  80  rotates about the first idler pulley  150  and returns to the loading zone of the first leg, where it may be reloaded. If the basket  80  is not biased toward the closed position, the basket may be closed by personnel or the lid portion may contact a ceiling surface of the cooking chamber  52  (e.g., defined by the cover plate  136 ) to urge the basket  80  to the closed position. In any event, each basket  80  continuously repeats movement along this path during operation of the fryer  10 . 
     As shown, the hopper  190  freely rests on a shelf  232  of the fryer manifold  48  below the unloading zone. In one embodiment, the hopper  190  is of a mesh or screen-like construction, such that any residual oil on cooked food product dispensed therein may drain from the hopper  190  back into the oil vat. The shelf  232  and/or hopper  190  are inclined downwardly toward the oil vat to promote such oil drainage. A crumb sieve  240  is positioned between the hopper  190  and the oil vat to remove residual crumbs or other particles from the oil as it drains into the oil vat. When a desired amount of cooked food product has been dispensed into the hopper  190 , the hopper  190  may be removed from the shelf  232  by a user. For example, the hopper  190  may be removed to the table top  40  for further preparation and/or handling of the cooked food product. 
     In the embodiment shown, cooking of the food primarily occurs in the lower portion  134  of the cooking chamber  52  during at least portions of the second, third, fourth, and fifth legs. Some cooking may occur in the middle portion  132  of the cooking chamber  52  depending on, for example, the particular configuration of the loop and the location of the surface of the oil  140 . In this regard, the chain conveyor  50  is advanced along the movement path via the motor  180  at a predetermined speed that corresponds to the required cook time of a particular food product in the oil  140 . It will be appreciated that the required cook time will vary depending on a number of factors such as the type of food product and the temperature of the oil  140 . To this end, the control panel  42  may be operatively coupled to the motor  180  to allow a user to select a desired speed of the chain conveyor  50  for a particular cooking operation. In addition or alternatively, the control panel  42  may be operatively coupled to one or more of the heating elements  142  to allow a user to select a desired temperature of the oil  140 . In any event, the movement speed may remain constant during a particular cooking operation such that each basket  80  of food product is cooked in the oil  140  for the same desired set point cooking time. 
     The movement path of the baskets  80  through the fryer  10  permits the fryer  10  to cook a large volume of food while remaining relatively compact in comparison to typical fryers. In one embodiment, a cooking operation in the fryer  10  may allow cooking food product at approximately twice the cooking rate of a standard two-well fryer of the same footprint. Thus, the fryer  10  is capable of cooking a high volume of food products in a relatively small space. 
     With specific reference now to  FIGS. 1-3 and 7 , the continuous oil filtration system  16  includes a filter housing  250  having a number of panels including a front panel  252 , a rear panel  254 , a top panel  256 , a bottom panel  258 , and side panels  260 ,  262 , and a door  264  which together define an interior space  270  of the filter housing  250 . As shown, the filter housing  250  is mounted to the cover plate  136  via brackets  272 . An inlet pipe fitting  280  and/or inlet pipe  282  define an inlet channel  284  and are fluidly coupled to the interior space  270  at or near the top panel  256 , such that gravity may promote dispensing of oil from the inlet channel  284  into the interior space  270 . Similarly, an outlet pipe fitting  290  and/or outlet pipe  292  define an outlet channel  294  and are fluidly coupled to the interior space  270  at or near a lowermost portion of the bottom panel  258 , such that gravity may promote flow of oil from the interior space  270  into the outlet channel  294 . In this regard, the bottom panel  258  is sloped toward the outlet channel  294 . Though not shown in detail, each of the inlet and outlet pipe fittings  280 ,  290  and/or pipes  282 ,  292  may be fluidly coupled to the cooking chamber  52  via hoses, for example. More particularly, the inlet pipe fitting and/or pipe  280 ,  282  may be fluidly coupled to a sump of the cooking chamber  52 , and an oil filtration pump (not shown) may circulate unfiltered oil from the sump to the inlet channel  284  for dispensing into the interior space  270  of the filter housing  250 . Similarly, the outlet pipe fitting and/or pipe  290 ,  292  may be fluidly coupled to, for example, the middle or lower portion  132 ,  134  of the cooking chamber  52  for dispensing filtered oil into the oil vat of the cooking chamber  52 . While the illustrated inlet channel  284  is spaced apart from the surface of the oil  140  in the interior space  270  of the filter housing  250 , the inlet channel  284  may be submerged in the oil  140  such that the oil being dispensed from the inlet channel  284  may not drop through the air. In this manner, aeration of the oil may be avoided. 
     A conveyor belt  300  is positioned in the interior space  270  below the inlet channel  284  for selectively advancing oil and/or debris contained therein through the interior space  270 . In this regard, the conveyor belt  300  is positioned over a driven sprocket gear  302  and an idler sprocket gear  304 , which engage with the conveyor belt  300  such that rotating the driven sprocket gear  302  drives the conveyor belt  300 . In the embodiment shown, the driven and idler sprocket gears  302 ,  304  are spaced apart from each other by a conveyor support assembly  310 . More particularly, the sprocket gears  302 ,  304  are mounted to respective brackets  312 ,  314  which are coupled together by a support shaft  316 . The length of the support shaft  316  may be adjustable to change the spacing of the sprocket gears  302 ,  304  such as, for example, to take in or take out slack in the conveyor belt  300 . In any event, belt support pads  318  are mounted to each of the brackets  312 ,  314  for supporting the conveyor belt  300 , particularly when under the weight of oil and/or debris dispensed thereon. 
     The continuous oil filtration system  16  includes a motor  320  mounted to the filter housing  250  for supplying rotary motion to drive the conveyor belt  300 . For example, the illustrated motor  320  includes a motor output shaft  322  which rotates when the motor  320  is activated, and the motor output shaft  322  extends through the side panel  260  into the interior space  270  and is coupled to the driven sprocket gear  302  so as to transmit the motion from the motor  320  and/or motor output shaft  322  to the driven sprocket gear  302  to drive the conveyor belt  300 . In the embodiment shown, counterclockwise rotation of the motor output shaft  322 , illustrated by the arrows A 2 , causes movement of the conveyor belt  300  in a generally counterclockwise direction, illustrated by the arrows A 3 . 
     In the embodiment shown, the conveyor belt  300  is of a mesh or screen-like construction such that oil  140  may pass therethrough while undesirable particles such as crumbs  340  contained in the oil  140  may not. In this manner, as the conveyor belt  300  is advanced, the crumbs  340  and some residual oil may advance therewith, while the remaining oil may pass through the conveyor belt  300  into a lower portion of the interior space  270  toward the outlet channel  294 . As shown, the conveyor belt  300  is inclined downwardly toward the outlet channel  294  to promote the flow of oil  140  toward the outlet channel  294  and/or through the conveyor belt  300  and thus limit the amount of oil  140  riding along the conveyor belt  300 . 
     A scraper  350  is mounted in the interior space  270  and is configured to contact the conveyor belt  300  to inhibit the advancement of the crumbs  340  traveling on the conveyor belt  300 . More particularly, the scraper  350  is positioned to contact the conveyor belt  300  as the conveyor belt  300  rotates about the driven sprocket gear  302  in order to force the crumbs  340  off of the conveyor belt  300 . As shown, the scraper  350  is mounted to the filter housing  250  via a bracket  352  and is constructed of a semi-flexible material so as to avoid interfering with the advancement of the conveyor belt  300  itself. For example, the scraper  350  may be constructed of a thin gauge stainless steel, spring steel, and/or Teflon®. It will be appreciated that the configuration and arrangement of the scraper  350  may vary from the illustrated embodiment without departing from the scope of the invention. In any event, a crumb bucket  360  is positioned adjacent the scraper  350  to receive the crumbs  340  scraped from the conveyor belt  300 . At various intervals, such as when the crumb bucket  360  is substantially filled, a user may access the crumb bucket  360  via the door  264  to empty and/or clean the crumb bucket  360 . In certain embodiments, this may be performed while the continuous oil filtration system  16  continues to operate. 
     As shown, the scraper  350  allows the residual oil on the conveyor belt  300  to pass therethrough. In some embodiments, such residual oil may cling to the conveyor belt  300  during the rotation about the driven sprocket gear  302  and after passing the scraper  350  may release from the conveyor belt  300  and pour into a lower portion of the interior space  270 . 
     In the embodiment shown, an unfiltered oil compartment  370  is defined within the interior space  270  around the inlet channel  284  and between the top panel  256  and the conveyor belt  300  so as to limit the space in which unfiltered oil (shown as oil with crumbs in  FIG. 7 ) may flow from the inlet channel  284 . For example, the illustrated unfiltered oil compartment  370  includes a forward wall  372 , a rearward wall  374 , and at least one side wall  376  extending therebetween. Each of the walls  372 ,  374 ,  376  extends downwardly from the top panel  256  toward the conveyor belt  300 . As shown, the rearward and side walls  374 ,  376  terminate at or near the conveyor belt  300  to prevent oil  140  from reaching the outlet channel  294  without first being filtered by at least one of the conveyor belt  300 , the scraper  350 , and/or the walls  374 ,  376  themselves. In this regard, the rearward and side walls  374 ,  376  are spaced apart from the conveyor belt  300  to allow oil  140  to pass therebetween while preventing crumbs  340  from passing therebetween. The forward wall  372 , on the other hand, is spaced apart from the conveyor belt  300  sufficiently to allow the crumbs  340  to pass therebetween so that the crumbs  340  may be advanced toward the scraper  350  for removal from the oil  140 . 
     Thus, the continuous oil filtration system  16  may ensure that substantially all of the oil  140  received from the cooking chamber  52  via the inlet channel  284  is sufficiently filtered prior to being returned to the cooking chamber  52  via the outlet channel  294 . In one embodiment, the motor  320  and/or pump may be operatively coupled to the control panel  42  such that a user may selectively activate an oil filtration cycle of the fryer  10  and thereby begin operation of the motor  320  and/or pump. In addition or alternatively, the motor  320  and/or pump may be continuously operated during a cooking operation of the fryer  10 , such that no dedicated filtration cycle is required. In this manner, advancement of the baskets  80  along their movement path and thus food product cooking may continue uninterrupted while the oil  140  is treated. 
     As described herein, various components of the fryer  10  such as the chains  60 ,  62 , baskets  80 , rollers  150 ,  152 ,  154 ,  156 ,  158 ,  160 ,  162 , and conveyor belt  300  are exposed to oil during cooking operations. Therefore, any or all of these components may be constructed of a highly corrosion resistant material such as, for example, 304 stainless steel. 
     While various legs of the movement path of the baskets  80  are shown and described herein as being “vertical” or “horizontal,” it will be appreciated that such legs may be substantially vertical or substantially horizontal. For example, such legs may be oriented within a few degrees of vertical or horizontal. In one embodiment, such legs may be oriented within 5° of vertical or horizontal. 
     While the present invention has been illustrated by the description of various embodiments thereof, and while the embodiments have been described in considerable detail, it is not intended to restrict or in any way limit the scope of the appended claims to such detail. Thus, the various features discussed herein may be used alone or in any combination. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the scope of the general inventive concept.