Patent Description:
Oil-based frying is commonly used as a cooking method for a wide range of food, such as poultry, fish, potato products, and the like. Commercial fryers include one or more fry pots (also referred to as cooking chambers) that are filled with a cooking medium such as oil or solid fats. Heat is typically provided to the cooking medium using an electrical heating element submerged in the cooking medium or a gas burner thermally coupled to the cooking medium through the walls of the fry pot. When the cooking medium reaches a preset cooking temperature, food products are placed into the cooking medium for a predetermined amount of time during which the food products are cooked by heat from the cooking medium. To facilitate insertion and removal of the food products, the food products are typically placed inside a container, such as a wire basket, and the container lowered into the cooking medium for the predetermined amount of time.

Thus, many conventional systems rely on manual intervention to move food products into, out of, and through a fryer. Such manual intervention can be undesirable. Even in recently-developed automated systems for moving the food product, the automatic movement systems have been highly complex and expensive, as well as sometimes harsh on the food product being moved through the fryer. As such, it is desired to improve methods of moving food product through a cooking system in these circumstances to improve reliability and reduce complexity and damage to the food product.

The cooking medium of a conventional fryer is normally re-used for multiple cooking cycles, which may include cooking cycles for different food products. However, the cooking medium degrades over time. This degradation may be due to contamination by particles shed by the food products being cooked and from chemical degradation due to heat, oxidation, and reactions with the food products. In addition, as food particles accumulate in the cooking medium, the flavor characteristics of the food particles may become infused in the cooking medium. This infusion may adversely affect the quality of cooked food. For at least these reasons, the cooking medium must occasionally be replaced and/or filtered. Known contemporary filtering systems require the operator to manipulate manual valves to route the cooking medium through the filter and to return it to a cooking vessel, e.g., a frypot, disposed within the fryer. Even experienced operators may open or close the valves incorrectly, which increases operating expenses through lost time. Periodically, the drain pan under the fryer may be removed for cleaning or to discard the cooking medium. If the operator forgets to replace the drain pan and opens the drain valve, the cooking medium drains onto the floor and is wasted, which greatly increases operating expenses.

Fryer manufacturers have recently developed improved fryer systems and methods to help address some of the shortcomings with conventional food product movement and filtration systems as set forth above. For example, the original assignee/Applicant of this application developed an automated fryer as shown in <FIG> and <FIG> and described in <CIT>, entitled "Automatic Fryer," the entire disclosure of which is hereby incorporated by reference herein. This fryer moves food products using a continuous flow of cooking medium through a series of gates, and the gates are selectively opened to allow batches of food product to move from portion to portion along the length of the fryer. The continuous flow of cooking medium is driven by a recirculating pump system, and the cooking medium is therefore continuously filtered during cooking operations. Technical advantages of this design include improved temperature uniformity of the cooking medium for all food products because the cooking medium is being continuously circulated, and the removal of manual food product movement with baskets. This fryer design improves the functionality and operation of conventional fryers, but further improvements and refinements of the design continue to be desirable. For example, the oil life span for this fryer design can be relatively short (when no "top off" procedure is used) and therefore could be improved.

Accordingly, it is desirable to further reduce and/or optimize the amount of cooking medium required to operate the fryers, while improving the temperature and/or flow characteristics of cooking medium in automated fryers, as well as the reliability of moving food product through a fryer in a cooking process. <CIT> refers to an apparatus for frying food products comprising a cooking tank intended to receive said food products to be fried in a cooking liquid introduced into said cooking tank, wherein it comprises a first grid element, able to act as a support surface for said food products, a second grid element arranged above said first grid element, so as to define a duct between said first grid element and said second grid element, and a conveyor device adapted to transport said food products along said cooking tank, through said duct. <CIT> refers to a method of controlling the movement and separation of snack food products being cooked continuously in a bath of hot cooking oil to the end of realizing a more uniform moisture content in the final product employing a plurality of paddle wheels with blades to rotate in a double action, ratcheting clockwise and counter-clockwise to penetrate and agitate vigorously the product pack.

According to the invention, an automatic cooking system for frying food products according to claim <NUM> and a method for automatically cooking food products according to claim <NUM> are provided. Sub-claims refer to embodiments of the invention.

In one aspect, the cooking vat is subdivided into separate portions by at least two gates.

In another aspect, the bottom surface of each lane in the cooking vat is angled upwardly along at least a portion of the length from the inlet end to the outlet end. In some embodiments, this upward angling is along an entire length from the inlet end to the outlet end.

In yet another aspect, the heating element is positioned on an external side of the cooking vat so as to transfer heat energy by conduction through the cooking vat and into the cooking medium.

In a further aspect, the heating element is positioned within the cooking vat along the bottom surface so as to transfer heat energy directly into the cooking medium, and the heating element defining a low profile to avoid impedance of the continuous flow of cooking medium in the lane.

In some embodiments, each lane is approximately <NUM> inches (<NUM>·<NUM>,<NUM>) wide between the sidewalls and approximately <NUM> inches (<NUM>·<NUM>,<NUM>) wide at the bottom surface, so as to contain about <NUM> pounds (<NUM>-<NUM>) of cooking medium volume.

In one aspect, each gate is rotatably coupled with the cooking vat to pivot between the closed and open positions. To this end, in some embodiments each gate is coupled to a support rod that defines a rotational axis for movement of the gate, the support rod being configured to be driven rotationally by a drive. In some embodiments, each gate is removably coupled to the cooking vat so as to allow for removal of the gate and cleaning of the cooking vat. For example, each gate includes a spring release mechanism for selectively and removably engaging the gate to the cooking vat.

According to an embodiment of the invention, a dividing and movement device is located in the cooking vat, which divides the lane into separate portions, and also selectively actuates to automatically and positively move batches of the food product between the separate portions of the lane as well as out of the cooking vat from the outlet end when a cooking process is completed. Several potential types of dividing and movement devices can be used.

In one such example, the device is provided by a series of baskets positioned sequentially along a length of the lane, wherein each basket is pivotally coupled to the cooking vat so that each basket can rotate between a first position in which a batch of the food product is held in a corresponding portion of the lane for cooking, and a second position in which the batch of the food product is moved into another portion of the lane or out of the cooking vat. In some embodiments each basket includes a rear wall and sidewalls that form a chute-like structure for moving the batch of the food product into another portion of the lane or out of the cooking vat.

In another such example, the device is provided by a conveyor including a belt that extends along a length of the lane and paddles that project outwardly from the conveyor, wherein the paddles divide the lane into separate portions, and the conveyor rotates to move the paddles along the lane to move batches of the food product. The cooking system may also include an outlet basket positioned to receive a batch of the food product from the conveyor following a cooking process, the outlet basket configured to rotate relative to the cooking vat to remove the batch of the food product from the cooking vat.

In a further example, the device is provided by a series of gates positioned sequentially along a length of the lane, wherein each gate is pivotally coupled to the cooking vat so that each gate can rotate to selectively hold batches of the food product in a corresponding portion of the lane for cooking, and then selectively and positively move the batches of the food product into another portion of the lane. The cooking system may also include an outlet basket positioned to receive a batch of the food product from the series of gates following a cooking process, the outlet basket configured to rotate relative to the cooking vat to remove the batch of the food product from the cooking vat. In some embodiments each of the gates is either flexible or spring-loaded so as to allow complete contact with adjacent portions of the cooking vat during rotation to move the batches of the food product. In some embodiments the heating element is positioned on an external side of the cooking vat so as to transfer heat energy by conduction through the cooking vat and into the cooking medium. In some embodiments the heating element is positioned within the cooking vat along a bottom surface so as to transfer heat energy directly into the cooking medium.

In accordance with an embodiment of the invention each gate is removably coupled to the cooking vat so as to allow for removal of the gate and cleaning of the cooking vat, and wherein each gate includes a spring release mechanism for selectively and removably engaging the gate to the cooking vat.

In one aspect, each gate is rotatably coupled with the cooking vat to pivot between the closed and open positions. In another aspect, each gate is coupled to a support rod that defines a rotational axis for movement of the gate, the support rod being configured to be driven rotationally by a drive.

In one aspect, the method includes circulating the cooking medium through the cooking vat using a pump to produce a continuous flow of cooking medium along the lane. The moving of the batch of food product is performed by the continuous flow of cooking medium.

In some aspects, the moving of the batch of food product is performed also by a dividing and movement device located in the cooking vat, which divides the lane into separate portions, and also selectively actuates to automatically and positively move batches of the food product between the separate portions of the lane as well as out of the cooking vat from the outlet end when a cooking process is completed.

In some embodiments, a total volume of cooking medium contained in each lane of the cooking vat is sized to enable pull off of <NUM>% to <NUM>% of the total volume for every hour of cooking operation, thereby allowing for periodic top off with new cooking medium of <NUM>% to <NUM>% every hour. For example, each lane in the cooking vat may contain a total cooking medium volume of <NUM> pounds (<NUM>·<NUM>) to <NUM> pounds (<NUM>,<NUM>·<NUM>). The heating element can be defined by a heater rod cast in an aluminum bar casing, a printed think profile heater, or other known heating devices. It will be understood that the various aspects and embodiments described above and throughout this application may be combined in any combination and sub-combination without departing from the scope of the invention.

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, explain the one or more embodiments of the invention.

Embodiments of the invention are directed to automatic cooking systems and methods of controlling a fryer, which reduce and/or optimize the amount of cooking medium required to operate the fryers, while improving the temperature and/or flow characteristics of cooking medium in automated fryers. To this end, the cooking vat of the system is designed with one or more heating elements out of the path of flow for cooking medium and/or food products, and multiple lanes for flow of cooking medium and/or food products, thereby reducing the total volume of retained cooking medium used in the cooking process. Moreover, the use of continuous oil flow and filtration in combination with the new profiles of the lanes in the cooking vat can reduce or remove altogether the need to discard used oil when a periodic top off with new oil/cooking medium is required. Furthermore, food product movement along the length of the lanes in the cooking vat is more reliably achieved using all embodiments of this invention. By improving the product movement characteristics and uniform heat transfer into the cooking medium in the automatic cooking system, the embodiments described herein help minimize waste of cooking medium and food products and therefore operate more efficiently than conventional fryer designs.

Turning with specific reference to the drawings, <FIG> and <FIG> show embodiments of the Prior Art fryer apparatus <NUM>, <NUM> developed by the Applicant of this application, and which several embodiments of the current invention further improve and refine. The following description of these Figures is incorporated from the <CIT> published application for the purposes of explaining some of the primary functionalities and features of automatic cooking systems, many of which are retained in the embodiments of the current invention described below.

Referring to <FIG>, fryer apparatus <NUM> may be defined by inlet end wall <NUM>, outlet end wall <NUM>, sidewalls, and bottom surface <NUM>. Fryer apparatus <NUM> may be configured to hold cooking medium <NUM>. Cooking medium <NUM> may be oil, a liquid shortening, a meltable-solid shortening, or the like. Fryer apparatus <NUM> may include a false bottom <NUM>, which may rest on a ledge <NUM>. The ledge <NUM> may be connected to outlet end wall <NUM>. False bottom <NUM> may be lifted off ledge <NUM> to facilitate easy cleaning of the fryer apparatus <NUM>.

Cooking medium <NUM> may be circulated through the fryer apparatus <NUM> by a pump <NUM> in a flow direction X to create a flume that transports food product throughout the cooking process. To this end, food product movement in this design of fryer apparatus <NUM> is primarily accomplished with flow of cooking medium. Cooking medium <NUM> may enter the fryer apparatus <NUM> through pump outlet <NUM>, flow in direction X through the fryer apparatus <NUM>, and back into the pump <NUM> through pump inlet <NUM>. Any suitable pump may be implemented for pump <NUM>, including, but not limited to, a centrifugal pump, a gear pump, a vane pump, a roller pump, or a diaphragm pump. A filter manifold <NUM> may be disposed such that the cooking medium <NUM> passes through the filter manifold <NUM> as it flows in direction X between pump inlet <NUM> and pump outlet <NUM>.

To facilitate the circulation of cooking medium <NUM>, false bottom <NUM> and ledge <NUM> may be spaced from inlet end wall <NUM>. A filter <NUM> may connect ledge <NUM> to inlet end wall <NUM>. The filter <NUM> may be perforated sheet metal or any other suitable material configured to allow oil to flow from pump outlet <NUM> to pump inlet <NUM> in flow direction X. The filter <NUM> is configured to prevent the food products from sinking below false bottom <NUM> and ledge <NUM> and to ensure the food products flow in direction X, along the flow of cooking medium <NUM>. Upon reaching outlet end wall <NUM>, the food products may be transferred to a holding station (not shown). A second filter (not shown) prevents food products from entering pump inlet <NUM>. The filter manifold <NUM> may include another filtering mechanism, such as a paper filter, metal mesh, or other mechanism suitable for use with heated cooking medium. Filter manifold <NUM> may be removable for easy cleaning of accumulated filtered particles. A heating element <NUM> may be disposed in fryer apparatus <NUM> for heating the cooking medium <NUM>. The heating element <NUM> may be an electric heater or any other suitable heating mechanism.

The flow of food products from inlet end wall <NUM> to outlet end wall <NUM> may be controlled by a plurality of gates. First gate <NUM>, second gate <NUM>, and third gate <NUM> are each in a lowered position when the food products are placed in the fryer apparatus <NUM>. In the lowered position, the first gate <NUM>, second gate <NUM>, and third gate <NUM> may each be in contact with the false bottom <NUM>, or located relative to the false bottom <NUM> such that food product does not pass by the first gate <NUM>, second gate <NUM>, or third gate <NUM> in the lowered position. First gate <NUM> will prevent the food products from continuing to move in flow direction X until first gate <NUM> is raised. After a predetermined period of time, first gate <NUM> may be raised and the food products may continue to flow in direction X due to the flow of the cooking medium <NUM>. After a second predetermined period of time, first gate <NUM> may be lowered. At this time, the food products are located in the cooking medium <NUM> between first gate <NUM> and second gate <NUM>. After a third predetermined period of time, second gate <NUM> is raised and the food products may continue to flow in direction X due to the flow of the cooking medium <NUM>. After a fourth predetermined period of time, second gate <NUM> may be lowered. The food products are then located in the cooking medium <NUM> between second gate <NUM> and third gate <NUM>. Similarly, after a fifth predetermined period of time, third gate <NUM> may be raised and the food products may continue to flow in direction X due to the flow of the cooking medium <NUM>. After a sixth predetermined period of time, third gate <NUM> may be lowered and the food products may be automatically transferred to a holding station (not shown) upon reaching outlet end <NUM>. Gates <NUM>, <NUM>, <NUM> may be raised and lowered along direction a.

Actuating the gates may occur by any suitable mechanism that blocks the flow of food products in one position, and allows food products to flow downstream of the gate in a second position. Actuating gates <NUM>, <NUM>, <NUM> by raising and lowering the gates is one exemplary embodiment from the prior design. Alternatively, gates <NUM>, <NUM>, <NUM> may be actuated to swing open about a pivot point. One example of such pivotable or rotatable gates is described below in connection with embodiments of the present invention. Regardless of the gate design used, the cooking process using gates <NUM>, <NUM>, <NUM> may allow cooking of multiple batches of food product to increase the output of fryer apparatus <NUM>.

Referring to <FIG>, a fryer apparatus <NUM> according to another embodiment of the Prior Art system is depicted. Fryer apparatus <NUM> may include first gate <NUM>, second gate <NUM>, third gate <NUM> and a holding station <NUM> at an outlet end <NUM>. After flowing downstream of third gate <NUM>, food products are automatically transferred to the holding station <NUM>. The fryer apparatus <NUM> may include a heat lamp <NUM>. The food products may be transferred to the holding station <NUM> by any suitable means, including a basket <NUM>. Basket <NUM> may be rotated to transfer the food products into the holding station <NUM>. In one exemplary embodiment, the basket <NUM> is defined by a first sidewall <NUM>, a second sidewall <NUM>, and a downstream wall <NUM>. This arrangement leaves the basket <NUM> open at the upstream end, which is adjacent to the third gate <NUM>. The open end allows the food products to flow downstream of the third gate and into the outlet end <NUM> of the fryer apparatus <NUM>. The first sidewall <NUM>, second sidewall <NUM>, and downstream wall <NUM> may be perforated to allow excess oil cooking medium to drain before the food products are transferred to the holding station <NUM>.

With reference to <FIG>, a first embodiment of the automatic cooking system <NUM> of the current invention is shown in further detail. The system <NUM> includes a cooking vat <NUM> with one lane <NUM> for cooking medium and food product movement, but it will be appreciated that more than one of the lanes <NUM> may be provided in larger versions of the cooking vat <NUM>. The cooking vat <NUM> is shown empty in these Figures. As with the designs of <FIG> and <FIG>, the cooking vat <NUM> includes a pump (not shown) and an oil recirculation system (not shown except for inlet and outlet pipes <NUM>, <NUM> extending from the cooking vat) to generate a continuous flow of cooking medium from an inlet end <NUM> of the cooking vat <NUM> to an outlet end <NUM> of the cooking vat <NUM>. Food products move from portion to portion along the lane <NUM> of the cooking vat <NUM> because of the cooking medium flow, with control of the food product movement provided by the series of gates <NUM> shown in <FIG>. The gates <NUM> are perforated and otherwise function in a similar manner as locks on a river. Thus, the food products can be retained in the heated cooking medium for a time sufficient for fully cooking the food products, and then the food products can be removed from the outlet end <NUM> of the cooking vat <NUM> at the completion of the cooking cycle. The cooking methodology and the use of continuous oil flow/filtration and gates is similar to the example described above, but other features are added or re-designed as follows.

As shown in <FIG>, the lane <NUM> of the cooking vat <NUM> in this embodiment is generally rectangular in cross-section, having a bottom surface <NUM> that is <NUM> inches (<NUM>·<NUM>,<NUM>) wide between the corners of the cooking vat <NUM>, in one example. To reduce the amount of cooking medium volume within the cooking vat <NUM>, the heating elements <NUM> are provided on the exterior of the cooking vat <NUM>. The heating elements <NUM> include a rod heater <NUM> cast into an aluminum bar <NUM> (or block), which is then coupled in face-to-face abutting contact with the bottom surface <NUM> of the cooking vat <NUM>. The heating elements <NUM> therefore transfer heat energy by conduction through the cooking vat <NUM> and into the cooking medium. By placing the heating elements <NUM> along an exterior of cooking vat <NUM>, the cooking medium and food products do not need to flow around the heating elements <NUM> and turbulent flow is reduced/avoided, which reduces oxidation of the cooking medium and thereby improves cooking medium lifespan.

In the example shown with a <NUM>-inch (<NUM>·<NUM>,<NUM>) wide lane, a heating element configured to output <NUM> to <NUM> kW was sufficient in testing results to heat the cooking medium in the cooking vat <NUM> to an operating temperature of at least <NUM>°F ((<NUM>·<NUM> - <NUM>)·<NUM>/<NUM>) and maintain the cooking medium at that temperature through multiple cooking cycles of food products. The large contact surface between the cast bar <NUM> of the heating elements <NUM> and the bottom surface <NUM> advantageously generates a uniform heat transfer and temperature in the shallow pool of cooking medium within the cooking vat <NUM>. The exemplary cooking vat <NUM> shown in this embodiment requires approximately <NUM> pounds (<NUM>·<NUM>) of cooking medium per lane <NUM>, to provide an oil depth of <NUM> inches (<NUM>,<NUM>·<NUM>,<NUM>), which provides desirable flow of batches of food products (of approximately <NUM> pounds (<NUM>,<NUM>·<NUM>)) from gate to gate <NUM> when the cooking medium is circulated using the oil recirculation system. Likewise, this embodiment of the automatic cooking system <NUM> reduces oil use compared to conventional fryer designs like the one shown in <FIG> and <FIG>, while also improving oil life, e.g., the total length of time or number of cooking cycles that can be performed before cooking medium replacement is required.

In testing of the embodiments of the automatic cooking system, several design parameters have been reviewed to evaluate effects on oil use and oil life span. For example, different heating methods such as heated air convection instead of the cast aluminum bar heating elements were tested, but these did not have any significant effect on oil life, so the most efficient heat transfer has been chosen (provided by the cast aluminum bar heating elements or low-profile heating elements such as printed heating elements described in further embodiments below). The pump in the oil recirculation system was also modified, using a gear pump and a centrifugal pump in different tests. These different pumps provided no discernable effect on oil life span, so the centrifugal pump has been chosen for these embodiments to reduce noise output and to enable a varying, controlled oil flow rate. The varying oil flow rate is enabled because of the variable frequency drive used with the centrifugal pump.

The test results have led to the conclusion that oil life span is primarily affected by oxidation effects. In addition, removal of turbulent oil flows and a reduction of the ratio of surface area to oil volume are believed to assist with improving cooking medium life span. One design parameter that has been proven to help with extending cooking medium life span is the use of "top off" with new cooking medium. According to further testing, increasing a top off percentage of the total oil volume in the cooking vat per hour of operation of the cooking process significantly improves oil life, up to about <NUM>% top off. Above this <NUM>% top off value, the further benefits to oil life span are not significant for the amount of additional new cooking medium that would be periodically added to the system. It will be understood that if a corresponding amount of cooking medium has not been pulled off by the cooking of the food products in the time period before a top off, some amount of used cooking medium would also need to be removed and discarded from the system so that the same amount of cooking medium volume remains for further operations following the top off. This discarding of cooking medium is a waste factor that should be minimized, if possible. Alternatively, if used oil is not removed from the cooking system during a top off, then the result of less "pull off" caused by the cooking operations is a lower percent of top off that happens to refill the cooking vat to the necessary depth, which is undesirable for oil life considerations.

Therefore, further embodiments of the automatic cooking system such as the cooking system <NUM> shown in the embodiment of <FIG> have been designed with the goal of optimizing oil use to reduce overall oil consumption and to reduce or eliminate the waste factor associated with discarding oil when a top off is required to extend oil life. In this regard, a design capacity for cooking <NUM> pounds (<NUM>-<NUM>) to <NUM> pounds (<NUM>·<NUM>) of French fries was set, with a goal to size the cooking vat and lane(s) such that the amount of cooking medium pulled out of the cooking vat by the food products and the cooking process (e.g., what occurs naturally as a result of frying food products) approaches the <NUM>% top off value. In other words, the size of lanes in the cooking vat in this second embodiment has been designed to achieve <NUM>%-<NUM>% pull off of cooking medium volume per hour of cooking operation, when <NUM> pounds (<NUM>-<NUM>) to <NUM> pounds (<NUM>·<NUM>) of food products have been cooked in that hour. Thus, when the periodic top off with new cooking medium occurs, an optimized amount of top off volume can be added to the cooking vat without necessitating discharge and discarding of much (or any) waste cooking medium. These design parameters led to the conclusion that a cooking vat with four parallel lanes could handle that amount of food products per hour, and achieving the <NUM>%-<NUM>% pull off could be done if the total retained oil volume within each lane was about <NUM> pounds (<NUM>-<NUM>) to <NUM> pounds (<NUM>-<NUM>) of cooking medium. Sufficient oil depth (<NUM> inches (<NUM>,<NUM>·<NUM>,<NUM>)) and flow to move the food products from gate to gate is only achieved with that total oil volume when the heating elements are positioned outside the cooking vat, as described above.

The specific four-lane cooking vat of the second embodiment of the automatic cooking system is shown in <FIG>. Each of the <NUM>-inch (<NUM>·<NUM>,<NUM>) wide lanes from the first embodiment is effectively replaced by two of the lanes <NUM> in the cooking vat <NUM> shown in <FIG>. To this end, each lane <NUM> is about <NUM> inches (<NUM>·<NUM>,<NUM>)wide at the top opening thereof, and the cross section of the lane <NUM> is modified to have chamfered corners <NUM> at the bottom to provide a hexagonal shape and a narrowed bottom surface <NUM> that is about <NUM> inches (<NUM>·<NUM>,<NUM>)in width. In addition, the bottom surface <NUM> of the lanes <NUM> are angled upwardly along at least a portion of the length from an inlet end <NUM> of the cooking vat <NUM> to an outlet end <NUM> of the cooking vat <NUM>, most clearly shown in <FIG>. The bottom surface <NUM> is angled upwardly along an entire length of the lane <NUM> in the illustrated embodiment. The oil, which levels out due to gravity, is therefore deeper at the inlet end <NUM> to assure full food product coverage when the food products are initially placed into the cooking vat <NUM>. The shallower depth at the outlet end <NUM>, where the cooked food products are removed for finishing at a packaging zone (schematically indicated at <NUM>) outside the cooking vat <NUM>, advantageously increases oil flow velocity towards the plumbing of the oil recirculation system. These revisions to the cooking vat <NUM> result in oil volume of about <NUM> pounds (<NUM>,<NUM>·<NUM>) per lane <NUM>. This is an improvement of oil volume use (<NUM> lanes use <NUM> pounds (<NUM>·<NUM>) of cooking medium as compared to <NUM> pounds (<NUM>·<NUM>) in the first embodiment) and approaches the calculated optimal value for <NUM>% top off, which would be <NUM> pounds (<NUM>·<NUM>) to <NUM> pounds (<NUM>-<NUM>) of oil volume per lane <NUM>. Thus, the cooking vat <NUM> and lanes <NUM> in the second embodiment improve oil life span by pulling off an amount of oil volume approaching a <NUM>% top off volume per hour of operation, while also significantly reducing the total oil volume needed within the cooking system <NUM>.

Moreover, the flow characteristics of the cooking medium and the food products are improved thanks to the design of the lanes <NUM> of the cooking vat <NUM>. The angled bottom surface <NUM> and the chamfered corners <NUM> at the bottom of the lanes <NUM> help avoid impeding cooking medium flow in a manner that would generate turbulence in the cooking medium that can increase oxidation of the oil (reduces oil life span) while also improving reliability of flow of food products from gate to gate <NUM> (one gate <NUM> shown in each lane <NUM>). The generally increasing velocity of oil along the length of each lane <NUM> also helps assure reliable food product movement from gate to gate <NUM>. Although not shown in these Figures, the heating elements are once again provided outside the interior of the cooking vat <NUM> to improve flow characteristics and avoid generation of turbulence in the cooking medium. Thus, the second embodiment of the automatic cooking system <NUM> provides several functional advantages, including improved oil life span, reduced oil volume use, and better flow of food products between inlet and outlet ends <NUM>, <NUM> of the cooking vat <NUM>.

As initially described above, the heating elements of the automatic cooking system <NUM> of this embodiment are designed to be heater rods cast in aluminum bars or blocks that are coupled to the bottom surface(s) <NUM> of the lanes <NUM> defining the cooking vat <NUM>, to thereby provide uniform heating of the cooking medium via conduction through the cooking vat walls. Other types of conductive heaters may also be used in other embodiments consistent with the scope of this invention, such as printed heating elements with a low profile. The heating elements of any design may be positioned and configured in various manners, with some other examples of exterior mounting shown in <FIG>.

Another embodiment of the automatic cooking system <NUM>, which is similar in overall structure to the second embodiment of <FIG>, is shown in <FIG> and <FIG> with two different configurations of heating elements <NUM>. To this end, the cooking vat <NUM> of this cooking system <NUM> includes four parallel lanes <NUM>, and <FIG> shows one configuration for heating elements <NUM> along the bottom surfaces <NUM> of the cooking vat <NUM>. Larger size heaters 72a are positioned across two or more of the lanes <NUM> adjacent the inlet end <NUM> of the cooking vat <NUM>, while smaller size heaters 72b are positioned on each lane <NUM> individually adjacent the outlet end <NUM> of the cooking vat <NUM>. The combination of larger and smaller heaters 72a, 72b collectively engages with a substantial majority of the surface area along the bottom surfaces <NUM> (the about <NUM>-inch-(<NUM>·<NUM>,<NUM>)wide surfaces) of each lane <NUM> of the cooking vat <NUM>, thereby enabling the uniform heat transfer desired and needed to maintain the cooking medium at operating temperatures of <NUM>°F ((<NUM>-<NUM> - <NUM>)-<NUM>/<NUM>) or higher. That arrangement of engagement with a large amount of surface area on the lanes <NUM> is maintained in each of the examples shown.

Turning to <FIG>, another configuration of the heating elements <NUM> is shown. Each lane <NUM> of the cooking vat <NUM> includes a single elongated heating element <NUM> connected to the about <NUM>-inch (<NUM>·<NUM>,<NUM>)wide bottom surface <NUM> thereof in this embodiment. The heating element <NUM> follows the angling of this bottom surface <NUM>, as described above in connection with the second embodiment of the system. Such an embodiment may be used to individually control the lanes <NUM> when such individual control is desired (e.g., when fewer than the maximum number of lanes <NUM> may be used in operation of the cooking system <NUM>). As will be understood, this and other embodiments of the cooking system <NUM> may use heating elements <NUM> that include rod heaters in cast blocks of aluminum, or printed heating elements, or other known designs for conducting heat into the cooking vat <NUM>.

In <FIG>, a further configuration is shown of a cooking system <NUM>, which includes similar elements as one of the lanes <NUM> in the cooking vat <NUM> shown in <FIG> (identical reference numbers are used where elements are unchanged from the embodiment described above). This cooking system <NUM> includes heating elements <NUM> mounted on the exterior of the cooking vat <NUM> along both the bottom surface <NUM> and the chamfered corner surfaces <NUM> at the bottom end of each lane <NUM> of the cooking vat <NUM>. The heating elements <NUM> of each configuration may be coupled to the cooking vat <NUM> using various methods, including but not limited to, welded studs on the bottom surface <NUM> of each lane <NUM>, and/or spring-loaded clamps. Regardless of the configuration and coupling mechanism chosen, the heating elements <NUM> provide uniform heating and temperatures within the cooking medium during cooking operations, and the heat transfer and temperature uniformity is further improved by the continuous flow of cooking medium through the cooking vat <NUM> and through the oil recirculation system.

<FIG> schematically illustrates in a sequence of views the history of fryer designs and the future, based on the developments in automatic cooking systems <NUM>, <NUM>, <NUM>, <NUM> like the ones described in the embodiments above. In <FIG>, the left pictorial shows a conventional fryer <NUM> from <NUM> and earlier. The fryers <NUM> of this era included a large volume of cooking medium, of which a portion defined a "cold zone" <NUM> below the operating area <NUM> where baskets <NUM> of food product would be cooked. As described above, these conventional fryers <NUM> required significant oil volume and use (schematically indicated by the <NUM> oil jugs) and manual intervention with the recirculation system <NUM> to conduct filtration cycles for oil life extension as well as basket movements of food products. In the middle pictorial in <FIG>, conventional fryer designs of the last few years (e.g., from <NUM> to <NUM>) are depicted. The large cold zone <NUM> of oil has been removed in such fryers <NUM> thanks in part to improved filtration systems, which also helps reduce oil volume use (indicated by the <NUM> oil jugs). The heating elements <NUM> are still located inside the cooking vat, however. As the use of cooking mediums such as trans-fat free oils are relatively expensive and have become desired by end consumers, the reduction of oil volume is important to achieving efficient operation of the cooking systems. Food product movement and management is still limited by the need for baskets <NUM> and manual intervention in such conventional designs, and filtration cycles for daily operation also typically require user intervention.

The potential future of frying technology is shown in the right pictorial of <FIG>. This is consistent with the automatic cooking system developed in <CIT> and further refined in the embodiments of this invention. To this end, these fryers <NUM> include continuous filtration (by updated recirculation system <NUM>) and automatic food product movement between cooking stations driven by cooking medium or by other driven movement devices, removing the need for manual intervention in the cooking process. One of the perforated gates <NUM> is also shown in <FIG> to show how oil can move through the fryer <NUM> while the food products are held in position for cooking (in embodiments where the cooking medium is used to move the food products, as set forth in several examples above). The continuous filtration and cooking vat design collectively result in a further significant reduction of oil volume use (indicated by the <NUM> oil jug). The improvements and advantages provided by the automatic cooking systems of this invention will help achieve the goal of minimized or optimized oil volume use, thereby improving the cost efficiency of operating such systems and performing associated cooking methods.

As initially noted above, when using cooking medium to automatically drive the food product flow along lanes of a cooking vat, the batches of food product may be held in different stations or portions of the lanes with at least one gate. The gate may be configured to actuate in several manners, but one exemplary embodiment of a rotatable and/or pivotable gate <NUM> used with the automatic cooking systems of this invention is shown in <FIG>. Beginning with reference to <FIG>, the gate <NUM> is designed to be mounted by welding or the like (at joint <NUM>) into position on a support or drive rod (hereinafter support rod <NUM>) that releasably connects into position at the cooking vat. The support rod <NUM> and the gate <NUM> are rotatably driven by a hex drive <NUM> that may be gear-driven by an input gear <NUM> as shown in <FIG>, in one example. The input gear <NUM> may receive rotation from a motor driven by a controller of the fryer (not shown in these Figures). It will be appreciated that different types of driving units for rotating the support rod <NUM> and the gate <NUM> may be used in other embodiments without departing from the scope of the invention.

The support rod <NUM> extends in use between two fixed hubs <NUM> located on opposite sides of the cooking vat. The support rod <NUM> includes a spring release mechanism <NUM> on opposing ends that releasably engages with the two fixed hubs <NUM> to lock the gate <NUM> in position at the cooking vat, and then release the gate <NUM> for removal when the gate <NUM> or the cooking vat require cleaning. The support rod <NUM> also defines a rotational axis for the gate <NUM>, which is generally horizontal in this embodiment so that the gate <NUM> can pivot rearwardly and upwardly away from the food product and cooking medium in the cooking vat to release flow of the food product to the next section of the cooking vat. Further details of the locking and unlocking operation of the support rod <NUM> and the spring release mechanism <NUM> are provided below with reference to pictorial views in <FIG>, but a cross-section showing the spring release mechanism <NUM> is provided at the top of <FIG> as well. The spring release mechanisms <NUM> are shown in a locked position in <FIG>, and in an unlocked position ready for release and removal of the gate <NUM> in <FIG>.

<FIG> and <FIG> illustrate several views of the gate <NUM> mounted in position at one embodiment of a cooking vat <NUM>, which is largely consistent in shape and profile to the lanes/vats described above for other embodiments of the automatic cooking system. To this end, the cooking vat <NUM> defines an elongated lane <NUM> with an angled bottom surface <NUM> and chamfered corner surfaces <NUM> at the bottom of the side walls <NUM>. The elongated lane <NUM> is divided into distinct cooking sections by the gates <NUM> (two shown in <FIG>, but it will be understood that more or fewer gates <NUM> and sections may be provided in other embodiments), and a batch of food product can be held within some or all these cooking sections during operation. To move food product from one cooking section to the next, one of the gates <NUM> rotates rearwardly and upwardly out of the path of oil movement along the length of the lane <NUM>, and the continuous oil flow through the cooking vat <NUM> then pulls the food product into the next cooking section (or the outlet end of the cooking vat <NUM>).

As shown most clearly in <FIG>, the gate <NUM> is shaped and sized to match the cross-sectional profile of the lane <NUM> and thereby occlude a substantial majority of the cross-section of the cooking vat <NUM> when in the blocking position shown, including following the side edge chamfered corner surfaces <NUM> at the bottom of the cooking vat <NUM>. The gate <NUM> includes perforations <NUM> or flow apertures <NUM> that are large enough to permit free flow of cooking medium therethrough but small enough to occlude movement of food product into the next cooking section. The apertures <NUM> are designed to substantially avoid having the flowing cooking medium create turbulence and/or significant waves when the gate is pivoted through the cooking medium between a blocking position and a raised position, while also avoiding generation of significant turbulent flows in the cooking medium during use in the normal blocking or occluding position in the cooking vat <NUM> (when the cooking medium must flow through and around the gate <NUM>). The pivotal movement of the gate <NUM> from the position shown in <FIG> and <FIG> both opens the flow path for food product such as fries to move along the length of the cooking vat <NUM> while also assisting with movement of food product to avoid having the food product become stuck in a previous cooking section.

Further constructional details of this embodiment of the gate <NUM> at the cooking vat <NUM> are shown in <FIG> and <FIG>. In this regard, the fixed hubs <NUM> that the support rod <NUM> releasably couples to are provided on vertical supports <NUM> that extend upwardly from edges <NUM> of the cooking vat <NUM> (e.g., proximate to the side walls <NUM>). The vertical supports <NUM> are configured to position the gate <NUM> at the appropriate occluding or blocking position when in the positions shown in <FIG> and <FIG>, while still allowing for rotation of the support rod <NUM> to pivot the gate <NUM> to an open position not shown in these Figures. The hex drive <NUM> and the input gear <NUM> may be located on an opposite side of one of the vertical supports <NUM> from the cooking vat <NUM>, which can help generally isolate these drive members from cooking medium and the environment at the cooking system. The gate <NUM> is also shown to include a narrowed profile near the joint <NUM> with the support rod <NUM> and a large material aperture <NUM> above the portion of the gate <NUM> configured to be in the cooking medium (the portion with the flow apertures <NUM>). These features of the gate <NUM> reduce the overall weight of the gate <NUM> to lessen the energy required to pivot between positions.

As shown in <FIG>, an automated basket <NUM> may be provided near the outlet end <NUM> of the cooking vat <NUM>. The automated basket <NUM> is typically mounted on a pivotable drive <NUM> in a similar manner as the support rod <NUM> for the gates <NUM>. The basket <NUM> includes a plurality of apertures <NUM> to avoid blocking flow or creating significant turbulence in the cooking medium flowing along the length of lane <NUM>. As will be readily understood from the cross-section in <FIG>, when the leftmost gate <NUM> pivots upwardly and rearwardly, any batch of food product that was previously held in position at that gate <NUM> can be carried by oil flow into the basket <NUM>, which defines a final cooking station within the lane <NUM>. The bottom surface <NUM> of the cooking vat <NUM> may include a step down <NUM> to accommodate the bottom of the basket <NUM>. However, the upward angling of the bottom surface <NUM> may still be maintained along at least a portion of the cooking vat <NUM> to achieve the improved flow characteristics of this invention. When a cooking cycle for a batch of food product is completed, the automated basket <NUM> is driven to rotate and remove the food product from the outlet end <NUM> of the cooking vat <NUM> and dump the cooked food product to a downstream prep station (an example of which was schematically illustrated and described in connection with a previous embodiment). Thus, manual intervention is avoided with the cooking vat <NUM> of this embodiment. The automated basket movement concept is shown in various other embodiments of this invention, including at the outlet end as shown in this and some prior embodiments, as well as along the length of the lane <NUM> in several alternative embodiments described in detail below.

Now turning to the pictorial views of <FIG>, further details of the support rod <NUM> for the gates <NUM> and the spring release mechanism <NUM> of this embodiment are shown. In <FIG>, the bottom side of the support rod <NUM> is facing the viewer so as to reveal an elongated slot <NUM> in which the top end of the gate <NUM> is welded or otherwise secured into position to form the aforementioned joint <NUM> when assembling the gates <NUM> of this embodiment. The permanent connection of the support rod <NUM> to the gate <NUM> allows for the support rod <NUM> to be driven to rotate by the hex drive <NUM> and gear <NUM> described above, which then leads to movement of the gate <NUM> into and out of blocking positions within the cooking medium and the cooking vat <NUM>.

In <FIG> and <FIG>, the support rod <NUM> is rotated from the view shown in <FIG> so that handles <NUM> on the spring release mechanism <NUM> can be shown (only the bottom securing nut <NUM> is visible for these handles in <FIG>). Comparing <FIG> and <FIG>, the support rod <NUM> of <FIG> is in the locked position where the spring release mechanism <NUM> is fully extended outwardly on both opposite ends of the support rod <NUM>, while the support rod <NUM> of <FIG> has both spring release mechanisms <NUM> (mounted on ends <NUM> of the support rod <NUM>) pushed inwardly towards a central portion <NUM> of the support rod <NUM> and against the internal spring bias (by springs <NUM> that normally bias the ends of support rod <NUM> outwardly into the fixed hubs <NUM> as shown in the cross-section of <FIG>) to reduce the effective length of this assembly. In the position in <FIG>, the spring release mechanisms <NUM> can disengage the ends <NUM> from the fixed hubs <NUM> provided on opposite sides of the cooking vat <NUM>, and this disengagement allows the support rod <NUM> and the gate <NUM> to be pulled out of the cooking vat <NUM> and away from the drive, such as for periodic maintenance and/or deep cleaning of the cooking vat <NUM> and of the gate <NUM>. To this end, the handles <NUM> of the spring release mechanisms <NUM> are fixedly coupled to the ends <NUM> of support rod <NUM>, and the central portion <NUM> of support rod <NUM> includes linear guide slots <NUM> in which the handles <NUM> can move between locked and unlocked positions. Thus, the handles <NUM> on the spring release mechanisms <NUM> can move the ends <NUM> of the support rod <NUM> inwardly along the linear guide slots <NUM> against the bias of the springs <NUM> captured between the ends <NUM> of the support rod <NUM> and the central elongate portion <NUM> of the support rod <NUM>. The disengagement and small clearance formed between the fixed hubs <NUM> and the ends <NUM> of the support rod <NUM> is shown in <FIG>, consistent with the pictorial view in <FIG>. In the position shown in <FIG>, <FIG> and <FIG>, the springs <NUM> bias the ends <NUM> of the support rod <NUM> outwardly into engagement with the fixed hubs <NUM>. Accordingly, the gates <NUM> and support rod <NUM> are advantageously configured for quick engagement and quick release relative to the cooking vat <NUM> of this and other embodiments of the invention.

By providing the rotatable gates <NUM> in the cooking vat <NUM> as shown in <FIG>, control of batches of food product moving through the fryer can be achieved in the automatic cooking system. As set forth above, in addition to assuring that all the food product correctly moves through the cooking vat <NUM> and the cooking process, this system achieves minimized oil volume use and improved flow characteristics as compared to conventional fryer designs in this field. The gates <NUM> also allow for easy cleaning of the cooking vat <NUM> and associated equipment when that cleaning or other maintenance becomes necessary. When the cooking vat <NUM> design is combined with the gates <NUM> described above and the heating elements (aluminum block heaters or printed heating elements, for example), the automatic cooking system achieves several technical effects and advantages, including improved oil life (and reduced oil volume usage) as well as more reliable food product movement through an automated fryer.

Now with reference to <FIG>, an alternative embodiment of a cooking system <NUM> is shown. The cooking system <NUM> of this embodiment is highly similar to the one previously shown in <FIG> (system <NUM>), and the identical elements from the prior embodiments such as the lane <NUM> and the cooking vat <NUM> are provided with the same numbers in this embodiment for the sake of brevity. The cooking system <NUM> of this embodiment includes low profile printed heating elements <NUM> located on an interior of the cooking vat <NUM>, specifically along the bottom surface <NUM> and the chamfered corner surfaces <NUM>. The printed heating elements <NUM> do not provide significant flow restriction to the cooking oil flowing in the lane <NUM>, so additional turbulence and oxidation that can lower the lifespan of the cooking oil is avoided in such an arrangement. It will be appreciated that internal or external heating elements of the types described herein may be combined in any combination (including with internal and external heating mixed together, for example) with the various embodiments of the automatic cooking system, without departing from the scope of the invention because these heating elements in all embodiments achieve uniform heating of the cooking medium without adding significant flow restrictions. In embodiments where the cooking medium continuously flows, as in most of the prior embodiments described herein, the steady flow of the cooking medium also helps achieve the uniform heating within the cooking medium.

Several automatic cooking systems are shown with reference to <FIG>.

With reference first to the embodiment shown in <FIG>, an automatic cooking system <NUM> includes a cooking vat <NUM> defining a lane <NUM> that is elongated for food product to move along during a cooking cycle. The dividing and movement devices in this cooking system <NUM> are defined by a plurality of baskets <NUM> oriented in a sequential row along the length of the lane <NUM>. Each of the baskets <NUM> defines a generally L-shaped configuration and includes a rear wall <NUM> which extends upwardly out of the cooking oil and is configured to hold food product in a corresponding portion of the cooking vat <NUM>. These portions may also be referred to as cooking stations in this specification. The rear wall <NUM> and adjacent portions of sidewalls <NUM> defining the basket <NUM> collectively provide a chute-like structure for guiding food product that is automatically dumped out of the basket <NUM> when movement to another cooking station or out of the cooking system <NUM> is required. To this end, each basket <NUM> typically holds the food product for a controlled set period of time, and then rotates to dump the food product into the next basket <NUM> in sequence. The final basket <NUM> in the sequence at the outlet end of the cooking vat <NUM> dumps fully cooked food product to a holding and packaging station (not shown), as in other embodiments.

Each of the baskets <NUM> defining the dividing and movement devices in this embodiment are pivotally coupled to the cooking vat <NUM>. This pivotal coupling may be removable as with the coupling of the gates in the prior embodiments. The baskets <NUM> are connected to a drive that can selectively rotate the baskets <NUM> between the base cooking position shown in <FIG> and the dump position shown by the middle basket <NUM> in the view of <FIG>. As can be seen in <FIG>, the aforementioned height of the rear wall <NUM> and the sidewalls <NUM> forms a chute that accurately delivers all of the food product in the basket <NUM> into the next basket <NUM>. The drive is controlled by a main controller of the cooking system <NUM> in a typical embodiment. The pivotal coupling joints <NUM> of the baskets <NUM> and the corresponding axes of rotation for pivoting the baskets <NUM> are shown to be located above a top of the cooking vat <NUM>, and it will be understood that vertical supports like the ones shown in <FIG> may be provided to support the baskets <NUM> in this manner. It will further be understood that while the baskets <NUM> are shown schematically as solid-wall pieces in these Figures, the baskets <NUM> are typically provided with a plurality of apertures or perforations that allow oil movement and draining during the pivot movement but block the undesired movement of food products between cooking stations. The cooking system <NUM> of this embodiment avoids manual intervention in managing food product movement during frying, and thereby improves the functionality and reliability of automatic cooking systems.

With reference to a further embodiment shown in <FIG>, an automatic cooking system <NUM> includes a cooking vat <NUM> defining a lane <NUM> that is elongated for food product to move along during a cooking cycle. The dividing and movement device in this cooking system <NUM> is defined by a conveyor <NUM> that extends generally linearly along a majority of the length of the lane <NUM>. The conveyor <NUM> includes a rotating belt <NUM> and a plurality of dividing paddles <NUM> extending transversely from the belt <NUM>. These elements of the conveyor <NUM> can be best viewed in <FIG>, where the cooking vat <NUM> is shown in phantom only. The paddles <NUM> define spaces therebetween which form cooking sections that move as the belt <NUM> rotates through the lane <NUM>. The paddles <NUM> are equally spaced along the belt <NUM> so that the sections for receiving batches of food product are substantially identical in size. The conveyor <NUM> can be controlled by a controller of the cooking system <NUM> to move continuously (relatively slow speed) or in set amounts at certain times after the food products have cooked at their current cooking stations for the desired amount of time. The conveyor <NUM> is positioned to help assure the food product is submerged in cooking medium as the food product moves through the lane <NUM> in the cooking process, and the top side of the conveyor <NUM> is typically positioned above the level of the cooking medium. However, the particular positioning of the conveyor <NUM> may be modified in other embodiments consistent with the scope of the invention. The conveyor <NUM> assures reliable movement of batches of food product through the cooking system <NUM> in a similar manner as the basket-based and oil-based movement embodiments described above.

The cooking system <NUM> of <FIG> also includes an outlet basket <NUM> located near an outlet end of the cooking vat <NUM> and at a terminal end of the conveyor <NUM>. The outlet basket <NUM> is pivotally coupled to the cooking vat <NUM> so that a fully cooked batch of food product can be removed from the lane <NUM> in a substantially identical fashion as described above with reference to the <FIG> embodiment. To this end, the outlet basket <NUM> dumps fully cooked food product to a holding and packaging station (not shown), as in other embodiments. The conveyor <NUM> is positioned relative to the outlet basket <NUM> to positively force all of a batch of cooked food product into the outlet basket <NUM> before rotating out of the path of the basket <NUM> such that it can rotate to dump the food product as shown in the progression of <FIG> and <FIG>. Likewise, the conveyor <NUM> is spaced from the inlet end of the cooking vat <NUM> to allow for access of food batches into the fryer before the paddle <NUM> moves to submerge and force the batch of food product to move through the lane <NUM> during the cooking process.

It will further be understood that while the conveyor <NUM> and its paddles <NUM> are shown schematically as solid-wall pieces in these Figures, these elements may be provided with a plurality of apertures or perforations that allow oil movement and draining during the movement but block the undesired movement of food products between cooking stations. The cooking system <NUM> of this embodiment avoids manual intervention in managing food product movement during frying, and thereby improves the functionality and reliability of automatic cooking systems.

Turning now with reference to another embodiment shown in <FIG>, an automatic cooking system <NUM> includes a cooking vat <NUM> defining a lane <NUM> that is elongated for food product to move along during a cooking cycle. The dividing and movement device in this cooking system <NUM> is defined by one or more flexible gates <NUM> (two shown in the Figures) that are positioned in a sequence along the length of the lane <NUM>. Each of the gates <NUM> defines a generally angled or L-shaped configuration and is configured to hold food product in a corresponding portion of the cooking vat <NUM>, e.g., cooking stations. The gates <NUM> are either formed from a slightly flexible material or are mounted in a spring-loaded manner such that when the gates <NUM> rotate, they run over and contact the entire surface of the interior of the cooking vat <NUM> at that corresponding portion or cooking station. To this end, each gate <NUM> typically holds the food product for a controlled set period of time, and then rotates to move the food product into the next cooking station, and the flexibility of the gates <NUM> assures that all of the food product in the batch is reliably moved to the next station. The gates <NUM> may also then be configured to flexibly rotate past one another even when their areas of rotation slightly overlap, which is typical in this embodiment. Alternatively, the gates <NUM> can be formed with interlacing fingers to allow for the rotation past one another in the overlapping area.

<FIG> illustrates a base position of the cooking system <NUM> in which the gates <NUM> hold batches of food product within corresponding cooking stations along the length of the lane <NUM>. <FIG> shows the cooking vat <NUM> in phantom to better illustrate the shape and positioning of the gates <NUM> in this base position. <FIG> shows the rightmost of the gates <NUM> rotated and it can be seen that the flexible nature of the gate <NUM> allows for the entire batch of food product to be picked up and moved into the next cooking station when the gate <NUM> rotates. Likewise, <FIG> shows the end of a rotation of the leftmost of the gates <NUM> which is when a batch of food product would be dumped into an outlet basket <NUM> at the outlet end of the cooking vat <NUM>. The outlet basket <NUM> is pivotally coupled to the cooking vat <NUM> so that a fully cooked batch of food product can be removed from the lane <NUM> in a substantially identical fashion as described above with reference to the <FIG> and <FIG> embodiments. To this end, the outlet basket <NUM> dumps fully cooked food product to a holding and packaging station (not shown), as in other embodiments. The gate(s) <NUM> are positioned relative to the outlet basket <NUM> to positively force all of a batch of cooked food product into the outlet basket <NUM> before rotating out of the path of the basket <NUM> such that it can rotate to dump the food product as shown in <FIG>, for example.

Each of the gates <NUM> defining the dividing and movement devices in this embodiment are pivotally coupled to the cooking vat <NUM>. This pivotal coupling may be removable as with the coupling of the baskets in the prior embodiments. The gates <NUM> are connected to a drive that can selectively rotate the gates <NUM> between the positions shown in <FIG> and described above. The drive is controlled by a main controller of the cooking system <NUM> in a typical embodiment. The pivotal coupling joints (not shown) of the gates <NUM> and the corresponding axes of rotation for pivoting the gates <NUM> are located above a top of the cooking vat <NUM>, and it will be understood that vertical supports like the ones shown in <FIG> may be provided to support the gates <NUM> in this manner. It will further be understood that while the gates <NUM> are shown schematically as solid-wall pieces in these Figures, the gates <NUM> are typically provided with a plurality of apertures or perforations that allow oil movement and draining during the pivot movement but block the undesired movement of food products between cooking stations. Furthermore, while rotation in one direction is shown in the Figures to move the gates <NUM>, rotation in an opposite direction may be used in other embodiments to move the batches of food product without departing from the scope of the invention. The cooking system <NUM> of this embodiment avoids manual intervention in managing food product movement during frying, and thereby improves the functionality and reliability of automatic cooking systems.

One further embodiment of an automatic cooking system <NUM> is shown in <FIG>, and once again, this cooking system <NUM> includes a cooking vat <NUM>. The cooking vat <NUM> of this embodiment defines two cooking chambers <NUM> separated by a middle wall <NUM> of the cooking vat <NUM>. It will be understood that more or fewer than two cooking chambers <NUM> may be provided in other embodiments. Within each of the cooking chambers <NUM>, a rotatable basket <NUM> is mounted so that the basket <NUM> can pivot relative to the cooking vat <NUM>. These baskets <NUM> are substantially identical to those described above in the embodiment of <FIG>, including the chute-like configuration for dumping food product out of the cooking chamber <NUM> when a cooking cycle is complete. The baskets <NUM> are shown in the base position for cooking food products in <FIG>, and then each of the two baskets <NUM> is shown individually rotated to a dump position in <FIG> and <FIG> to move the cooked food product to a holding or packaging station outside the cooking vat <NUM>. As with prior embodiments, a main controller of the cooking system <NUM> can individually pivot the baskets <NUM> when needed to move the food product. The baskets <NUM> allow for the avoidance of manual intervention when managing the cooking process and moving food product, thereby improving the functionality and reliability of automatic cooking systems.

The various embodiments of automatic cooking systems described herein address many of the shortcomings of prior designs by improving upon recent developments in the fryer technology. To this end, improved oil span life and reduced oil use can be achieved, as well as reliable movement of food product into, out of, and through a cooking vat. Regardless of the combination of features used from the embodiments above, the cooking system and method of the present invention achieves these technical effects.

Claim 1:
An automatic cooking system for frying food products, comprising:
a cooking vat (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) configured to hold a cooking medium and to receive food product, the cooking vat defining at least one lane extending between an inlet end where the food product is inserted into the cooking vat and an outlet end where the food product is removed from the cooking vat, wherein each of the at least one lane of the cooking vat includes a bottom surface and sidewalls extending along the at least one lane, with chamfered corner surfaces connecting to the bottom surface and the sidewalls at an angle, wherein the bottom surface of each of the at least one lane in the cooking vat is angled upwardly along at least a portion of a length from the inlet end to the outlet end;
a heating element (<NUM>, <NUM>, <NUM>, <NUM><NUM>, <NUM>, <NUM>) coupled to the cooking vat and configured to transfer heat into the cooking medium to uniformly heat the cooking medium;
an oil recirculation and filtration system including a pump in communication with the inlet end and the outlet end of the cooking vat, the oil recirculation and filtration system configured to generate a continuous flow of cooking medium from the inlet end to the outlet end; and
at least one gate (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) located in the cooking vat and separating the at least one lane into separate portions, each of the at least one gate being configured to allow cooking medium flow therethrough, and also being configured to move between a closed position blocking flow of food product between adjacent portions of the at least one lane and an open position permitting flow of food product driven by the continuous flow of cooking medium past the at least one gate to an adjacent portion of the at least one lane,
wherein the heating element and at least one gate are positioned and configured to reduce impeding of the continuous flow of cooking medium in the at least one lane in such a manner that would generate turbulent flow, such that the flow of cooking medium over the bottom surface and chamfered corner surfaces and through the at least one lane reduces turbulence that can oxidate and reduce life span of the cooking medium,
wherein each of the at least one gate includes a plurality of flow apertures to allow the continuous flow of cooking medium through a length of the at least one lane.