Abstract:
A hot oil fryer for continuous frying duty in continuous food process lines has a conveyor belt that has an upper food-carrying upper run and a lower return run. Heat input is provided by rectangular or square heat exchanger tubes that are placed directly underneath the food-carrying run in order to support it from sagging as well as cut-down the span between the source of heat flowing inside the heat exchanger tubes and the sink of heat in the food product that is transported on top of the conveyor&#39;s food-carrying run. The conveyor includes an entrant ramp section having at least high and low operative positions. The cooking channel at the intake end is provided with a series of gutters as well as sediment drains to afford collection and filtration of floating debris as well as sinking debris.

Description:
CROSS-REFERENCE TO PROVISIONAL APPLICATION(S)  
       [0001]    This application claims the benefit of U.S. Provisional Application No. 60/171,316, filed Dec. 21, 1999. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    1. Field of the Invention  
           [0003]    The invention generally relates to hot oil fryers for the continuous hot oil frying of large quantities of food products as in large scale food process lines. More particularly, the invention relates to improvements in sediment removal from the cooking oil, for extending the use life of the cooking oil; as well as, reduced height heat exchanger banks that permit a shallower oil level in the cooking channel, and hence reduce the quantity of cooking oil needed to fill the system. Additional aspects and objects of the invention will be apparent in connection with the discussion further below of preferred embodiments and examples.  
           [0004]    2. Prior Art  
           [0005]    [0005]FIG. 1 shows a representative deep fat fryer  18  in accordance with the prior art. It&#39;s for the continuous deep fat frying of large quantities of food product in a large scale food process line. The apparatus as generally shown by FIG. 1 is more particularly depicted and described in connection with U.S. Pat. No. 5,074,199—Miller, owned by Stein, Inc., of Sandusky, Ohio. That patent reference is incorporated herein by this reference to it. The vantage point of FIG. 1 is aimed at the discharge end of the fryer apparatus  18 . Hence with reference to FIG. 1, the fryer apparatus  18  comprises a rigid unitary frame or housing  20 . The frame  20  extends axially from the discharge end to the infeed end of the apparatus  18 , and extends vertically up from the floor to the level of apron members  21 . The apron members  21  are directly secured to the top of the frame  20  and are connected in a unitary manner with a lining which forms an elongated horizontal oil tank or “cooking channel”  22 .  
           [0006]    The cooking channel  22  is defined by front and rear walls, spaced side walls and a bottom wall (eg., the bottom wall is indicated as  22   1  in FIG. 3). FIG. 7 gives another view of a cooking channel. The cooking channel will hold a volume of cooking liquid or oil (eg., or sometimes else known as “fat,” as in “deep ‘fat’ frying”). The frame  20  includes feet  20   a.    
           [0007]    Mounted near the four corners of the fryer apparatus  18  are four upright jacks  23 . The jacks  23  are preferably hydraulic and likely incorporate vertically extending piston rods  23   a.  The piston rods  23   a  are connected at their upper ends to respective cross bars  24   a  and  24   b.  Wherein, cross bar  24   a  is near the infeed end of the apparatus (ie., the far end in FIG. 1) and cross bar  24   b  is near the discharge end (ie, the near end in FIG. 1). Mounted above these cross bars  24   a  and  24   b  is an elongated hood or cover  25 . The hood or cover  25  has a rectangular recess or opening  25   a  at its lower side which makes a generally close fit with the aprons  21  when the apparatus  18  is in its nested or “closed” position for a cooking operation as illustrated in FIG. 2. The hood  25  may be provided with exhausts or vents (not shown) for exhausting gases or venting steam produced in association with the frying operation.  
           [0008]    The fryer  18  includes a pair of cooperating conveyors  26  and  30 , wherein the overhead conveyor  26  is a “submerger” conveyor and the underneath conveyor  30  is the main tractor or food-carrying conveyor. Frying food product (not shown) is transported through the cooking channel  22  compressed between these two conveyors  26  and  30 .  
           [0009]    The submerger conveyor  26  has spaced parallel outer side rails  26   a.  It is suspended as shown in FIG. 1 by its outer side rails  26   a  hanging on a set of four (4) relatively short chains  27 . One pair of the chains  27  is connected to the cross bar  24   a  at the infeed end of the fryer  18 , and the other pair of the chains  27  is connected to the cross bar  24   b  at the discharge end. The main tractor or food-carrying conveyor  30  has spaced parallel outer side rails  30   a,  and it is suspended by its outer side rails  30   a  hanging from a set of four (4) relatively longer chains  31 . A pair of these relatively longer chains  31  is connected with the cross bar  24   a  near the infeed end of the fryer  18  as the two other of the relatively longer chains  31  are connected with the cross bar  24   b  near the discharge end of the fryer.  
           [0010]    Reference may be had to an early U.S. Pat. No. 3,757,672—Szabrak et al., for a more detailed discussion of the fryer  18 &#39;s construction and operation, which patent reference of Szabrak, et al., is also incorporated herein by this reference to it. Basically, main tractor conveyor has an upper, food-carrying run  30   1  (as well as a lower return run  30   2 ). The submerger conveyor  26  has a lower, food-submerging run  26   1  (in addition to its upper return run  26   2 ). In use, the upper or food-carrying run  30   1  of the main tractor conveyor  30  supports the food product during transport through the cooking channel  22  concurrently as the lower or food-submerging run  26   1  of the submerger conveyor  26  presses the food product down sufficiently to keep it from floating off.  
           [0011]    To maintain compression between the food-carrying run  30   1  and the food-submerging run  26   1  of conveyors  30  and  26 , respectively, requires reinforcement being given to both runs  30   1  and  26   1 . FIG. 2 shows that the opposed runs  30   1  and  26   1  are oppositely reinforced. That is, the food-carrying run  30   1  is reinforced by a beds of rollers  32  whereas the food-submerging run  26   1  is reinforced by a ceiling of like rollers.  
           [0012]    [0012]FIG. 1 shows the fryer  18  in an open position. The side rails  30   a  of the main conveyor  30  are hoisted up well above and out of the hot bath of oil in the cooking channel  22 . The side rails  26   a  of the submerger conveyor  26  are hoisted up even higher, as over the main conveyor  30 . The hood  25  is shown disposed elevated even above the submerger conveyor rails  26   a.  This open position of the fryer  18  as shown by FIG. 1 allows the manual clearing of food product blockage from the conveyors, or more generally, the open position facilitates inspection, cleaning and maintenance.  
           [0013]    [0013]FIGS. 2 and 3 do not strictly depict the same fryer configuration  18  as shown by FIG. 1. More particularly, the fryer  18 ′ of FIGS. 2 and 3 is adapted from a pair of patent references which are commonly owned by Stein, Inc., consisting of not only the aforementioned U.S. Pat. No. 5,074,199—Miller, but also U.S. Pat. No. 5,253,567—Gunawardena, which latter patent reference is likewise incorporated by this reference to it.  
           [0014]    The predominant distinction between the FIG. 1 fryer  18  and the FIGS. 2, 3 fryer  18 ′ relates to location of the heat exchanger units  36 , 38  relative to the main tractor conveyor  30 . In FIG. 1, the heat exchanger units  36 , 38  are situated completely below both runs  30   1  and  30   2  of the main tractor conveyor  30 . In FIGS. 2 and 3, the heat exchanger units  36 , 38  are situated between the two runs  30   1  and  30   2  of the main tractor conveyor  30 . Indeed, in FIGS. 2 and 3, the lower or return run  30   2  scrapes along the bottom  22   1  wall of the cooking channel  22 .  
           [0015]    With more particular reference to FIGS. 2 and 3, the fryer apparatus  18 ′ includes fore and aft heat exchanger units or “banks”  36  and  38  of what are known as indirect-fired type heat exchangers. Unlike direct-fired types (wherein the heat exchangers are actually flues venting the combustion gases of a combustion source), indirect-fired heat exchangers circulate a recycled hot medium that is heated by a remote combustion or heat source  44 . Preferably the circulating hot medium is another oil or else steam:—oil is probably more common because it is less difficult to manage than steam.  
           [0016]    The forward heat exchanger bank  36  occupies the front or infeed half of the cooking channel  22  as the aft bank  38  is situated in the rear or discharge half of the cooking channel  22 . The heat exchanger banks  36  and  38  are adapted for heating the bath of cooking oil or fat within the cooking channel  22  to a desired temperature (eg., ˜400° F.-500° F.). In use, the heat exchange units  36  and  38  are submerged in the deep fat bath of the fryer.  
           [0017]    Each heat exchange bank or unit  36  or  38  comprises a plurality of vertically oriented heat transfer “plates”  40 . Although, these “plates”  40  are actually vessels that have hollow cores which define a flow channel therein. As shown by FIGS. 2 and 3, the bank or banks of heat exchangers  36 , 38  are positioned below the roller bed  32  of the main food carrying run  30   1  of the main conveyor  30 , and above the return run  30   2  thereof. Each heat-exchanger bank  36 , 38  has an inlet manifold  42  and inlet piping  44   a  on one extremity and an outlet manifold  42  and outlet piping  46   a  at its opposing extremity. The inlet and outlet manifolds  42  are coupled to each of the heat exchanger plates  40  to uniformly introduce the re-circulating hot medium to each.  
           [0018]    The design of the heat-exchanger “plates”  40  can partly be reckoned from inspection of FIG. 2. No doubt, the design of the heat-exchanger “plates”  40  is more particularly described and depicted in the aforementioned patent reference of Gunawardena. But with reference to FIG. 2, each heat exchanger plate  40  typically comprises at least two sheets of stainless which are secured together to form a pressurized vessel. The opposite sheets may be “dimpled” together in places by tack weld or, that is, employ a double embossed design which has inflated zones on both sides. In this manner, a plurality of pockets are formed such that the core or flow passage in any given plate-like vessel  40  causes the circulating hot medium to split into separate tendrils, which tendrils are directed to braid and intertwine with one another through the course of the flow passage. The sheets are sealed by welding about their edges to form such a hollow “plate”  40 .  
           [0019]    The heat-exchanger plates  40  are generally vertically oriented on edge and spaced laterally across the width of the cooking channel  22 . Also, the plates  40  are connected at each end by the inlet manifold  42 / 44   a  and exit manifold  42 / 46   a,  respectively. The vertical, on-edge orientation of the plates  40  and the spacing therebetween permits bread crumbs or food particles to fall through. That is, bread crumbs or other sediment which falls through the food-carrying run  30   1  as well as the bed of rollers  32 , ought to get clearance between the vertical plates  40  to land on the bottom wall  22   1  of the cooking channel  22 . The return run  30   2  of the main conveyor  30  will motivate or push such sediment along the bottom wall  22   1  of the cooking channel  22  (see, eg., FIG. 3) with the intention that such sediment will ultimately be removed from the oil system by a sediment-discharge auger  48 .  
           [0020]    [0020]FIG. 3 shows diagrammatically that the return or sediment-transporting run  30   2  of the main food conveyor  30  indeed travels fairly closely along the bottom wall  22   1  of the cooking channel  22 . Hence the return or sediment-transporting run  30   2  catches and facilitates removal of sediments comprising food particles which have fallen from food products on the main food-carrying run  30   1  and sunk to the bottom  22   1  of the cooking channel  22 . These types of sediment materials are removed from the fryer  18 ′ by means of the sediment-carrying run  30   2  pushing the sediment along the bottom  22   1  of the cooking channel  22  until the cooking channel  22  opens into a sediment-removal well  22   2 . The sediment-removal well  22   2  is positioned at the discharge end of the return or sediment-transporting run  30   2 . The sediment-removal well  22  has a deep end which is occupied by the discharge auger  48 .  
           [0021]    The main food conveyor  30 —including its main food-carrying run  30   1  and sediment-transporting return run  30   2 —is typically formed from an endless conveyor belt constructed of a wire mesh, as shown by for example, FIG. 6. Such a wire mesh belt is driven by conventional means such as a chain drive or hydraulic system and the like.  
           [0022]    The fryer  18  is likely provided with sensors associated with the housing  20  and/or hood member  25 , which in conjunction with an electronic control system (not shown) will indicate whether the hood  25  is in a closed position to enable operation of the apparatus, or whether hood  25  is opened which will render the apparatus inoperative for safety purposes. Other sensors (not shown) associated with the apparatus  18  may include a low oil level sensor and temperature sensors to allow precise control of temperature of the cooking oil throughout the cooking cycle within the apparatus  18 . Additional safety features associated with the apparatus  18  may comprise high temperature cutoff or limiting switches flame sensors or the like which will automatically shut down operation of the apparatus upon the occurrence of unsafe conditions in its operation. An electronic control system may be used to control all of the various aspects of operation of the fryer apparatus accordingly.  
           [0023]    Shortcomings with prior art fryer apparatus relate to the excessive volume of cooking oil required to charge the oil system at one time, as well as to sediment removal. It is desirable to minimize the charge or volume of cooking oil needed to keep the fryer in service during use, as much as practicable. In other words, it is desirable to get by on as low of cooking oil volume as practicable. The prior art design of the heat exchanger plates  40  has the flattened plate-like pressure vessels sitting on edge to present a relatively tall aspect that must be all submerged by cooking oil. And then, at an elevation above the heat exchangers, an intervening bed of rollers which support the food-carrying run from sagging spread out the distance between the source of heat (ie., the heat exchangers) and the sink of heat (ie., the food product transiting on the food-carrying run of the conveyor). Cooking oil must be poured into the channel to support this intervening bed of support rollers too.  
           [0024]    Minimizing cooling oil volume is important for large scale food processing applications for a variety of reasons. With a low volume of cooking oil, it is easier to keep the cooking oil in circulation. Sediments might be more efficiently strained and filtered out of the cooking oil. Also, poor oil circulation within the fryer tank and/or cooking channel creates hot spots which affords decomposition of the oil, and/or rises in the free fatty acids. Un-removed sediments which char in the hot oil contribute further to decomposition of the oil, with a greater likelihood of unpleasant tasting food products. Once that happens, the cooking oil must be changed out, with the old oil being discarded. The replacement of the cooking oil is one cost users of frying apparatus would like to minimize because simply, the cost of replacement cooking can add up and be significant over time. Just as importantly, users would like to avoid or minimize the down time that the whole food process line suffers because of the hold-up associated with a change-out of the cooking oil in the fryer.  
           [0025]    What is needed is an improvement which overcomes the shortcomings of the prior art.  
         SUMMARY OF THE INVENTION  
         [0026]    It is an object of the invention to provide a hot oil fryer for continuous frying duty in continuous food process lines which has a compact oil bath for getting by operating with a reduced volume of cooking oil.  
           [0027]    It is an alternate object of the invention that the above hot oil fryer have an entrant ramp section that is operative alternatively between at a high and low position.  
           [0028]    It is another object of the invention that the above hot oil fryer have various sediment drains as well as gutters to improve the collection and ultimate filtration of not only sinking debris but also floating debris.  
           [0029]    These and other aspects and objects are provided according to the invention in a hot oil fryer for continuous frying duty in continuous food process lines. The fryer includes a cooking channel having a bottom wall between spaced sidewalls and spaced end walls for containing cooking oil to a given fill level. The fryer also has a conveyor belt which has an upper food-carrying run and a lower sediment-motivating run. The lower sediment-motivating run is disposed to traverse along the cooking channel bottom wall for motivating sediment in direction of an intake end of the cooking channel. Otherwise the conveyor belt is disposed in the cooking channel such that a majority of both runs can be sunk below the given fill level of the cooking oil.  
           [0030]    The fryer moreover includes a bed of rectangular or square heat exchanger tubes arranged in spaced rows that extend parallel to the runs of the conveyor. In the cases of rectangular tubes, each is disposed upright with the narrow sides being top and bottom and the broad sides being vertical. This bed of heat exchanger tubes is interposed between the conveyor belt&#39;s upper and lower runs such that the top sides of the tubes cooperatively support the upper food-carrying run against sagging and also cut-down the span between the source of heat flowing inside the heat exchanger tubes and the sink of heat in the food product that is transported on the food-carrying run. A heat input system is provided for servicing the heat exchanger tubes with a heat medium.  
           [0031]    The conveyor belt likely comprises an open mesh design having a pattern that presents a series of spaced seams. If so, the heat exchanger tubes are sized and arranged in the bed such that some gaps between adjacent tubes accommodate the sliding transit of the seams therealong as other gaps do not and thereby afford clearance for sediment sinking from the upper food-carrying run to the lower sediment-motivating run.  
           [0032]    The fryer is likely provided with a cooking oil filtration system which interfaces with the cooking channel at least by an intake associated with the cooking channel&#39;s intake end.  
           [0033]    The fryer preferably includes a submerger system disposed directly above the conveyor belt&#39;s food-carrying run in order to submerge food product below the given fill level of the cooking oil during transit through the cooking channel. Needless to say, there is also a drive input system for driving the conveyor.  
           [0034]    Another optional aspect of the fryer pertains to the cooking channel having its bottom wall deepening at the intake end to define a pair of debris collection wells which are partitioned by a transverse wall into an inboard debris collection well and an outboard debris collection well. The conveyor correspondingly includes an entrant ramp section that is operative in the intake end&#39;s inboard debris collection well at least alternatively between a high-ramp configuration a low-ramp configuration. That way, the lower sediment-motivating run of the entrant ramp section motivates debris into the outboard well if in the high-ramp configuration or else into the inboard well if in the low-ramp position.  
           [0035]    More particularly, the way in which the lower sediment-motivating run of the entrant ramp section motivates debris into the outboard well if in the high-ramp configuration includes the following. That is, the fryer includes a convertible incline panel. The convertible incline panel is removable underneath the entrant section&#39;s lower sediment-motivating run when it is in the high-ramp configuration. When installed, the convertible incline panel extends from an origin about where the cooking channel deepens to a termination in or over the outboard debris collection well. This convertible incline panel provides support against sagging to the entrant section&#39;s lower sediment-motivating run as well as affords the sliding transit of sediment thereacross until ejected over the termination that is in or over the outboard debris collection well.  
           [0036]    Another aspect of the fryer pertains to the sidewalls of the cooking channel where flanking the inboard debris collection well are formed low, or as low as about even with the given fill level of the cooking oil. The low sections of the sidewalls are thus provided with gutters that afford the spillover and removal of floating debris, or presumptively floating debris. Preferably these gutters drain into the outboard debris collection well. The outboard debris collection well may be itself no more than a gutter attached to the transverse partition wall&#39;s upper edge.  
           [0037]    About that transverse partition wall, preferably it has an upper edge that generally corresponds to the given fill level of the cooking oil. In the matters of the cooking oil filtration system, it likely interfaces with at least the inboard and outboard debris collection wells, and perhaps the gutters too.  
           [0038]    Additional aspects and objects of the invention will be apparent in connection with the discussion further below of preferred embodiments and examples.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0039]    There are shown in the drawings certain exemplary embodiments of the invention as presently preferred. It should be understood that the invention is not limited to the embodiments disclosed as examples, and is capable of variation within the scope of the appended claims. In the drawings,  
         [0040]    [0040]FIG. 1 is a perspective view of a deep fat fryer of the prior art;  
         [0041]    [0041]FIG. 2 is an enlarged scale, partially broken, section view taken along the line II-II in FIG. 1, except including modifications also known from the prior art;  
         [0042]    [0042]FIG. 3 is an enlarged-scale, diagrammatic side elevational view generally corresponding to the prior art fryer of FIG. 2;  
         [0043]    [0043]FIG. 4 a  is an axial, vertical section view of a fryer in accordance with the invention for large scale food process lines, with portions broken away;  
         [0044]    [0044]FIG. 4 b  is a diagrammatic section view taken along line IVB-IVB in FIG. 4 a,  with portions shown in phantom line;  
         [0045]    [0045]FIG. 5 is a top plan view of an alternate embodiment of the fryer in accordance with the invention for large scale food process lines, with portions broken away  
         [0046]    [0046]FIG. 6 is a top plan view of a wire mesh conveyor belt of the prior art;  
         [0047]    [0047]FIG. 7 is a perspective view of a heat exchanger arrangement in accordance with the prior art, disposed in a fryer cooking channel;  
         [0048]    [0048]FIG. 8 is an enlarged-scale transverse section view of the FIG. 7 heat exchanger arrangement in accordance with the prior art, with a belt included to depict its position with the heat exchanger tubes;  
         [0049]    [0049]FIG. 9 a  is a transverse section view comparable to FIG. 8 except showing the heat exchanger tubes arranged in accordance with the invention; and, FIG. 9 b  is a transverse section view comparable to FIG. 9 a  except showing an alternate arrangement of heat exchanger tubes in accordance with the invention.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0050]    [0050]FIGS. 4 a  and  4   b  show an inventive fryer  100  configured with a sediment removal system  105  in accordance with the invention. The fryer  100  has a main food-carrying conveyor  110  which can take the form of, for example and without limitation, a wire mesh belt  120  as shown by FIG. 6. Staying in FIG. 4 a,  the main food conveyor  110  has an upper food-carrying run  110   1  and a lower, sediment-transporting run  110   2 .  
         [0051]    [0051]FIG. 4 a  shows the intake end of the fryer  100 , which is where food product enters the fryer  100 . The main food conveyor  110  has a central level section  114  and an entrant ramp section  116  that is adjustable relative to the main level section  114  between a high extreme (one high position is indicated as  116   H  and shown in solid lines), and, a low extreme (a low position is indicated as  116   L  and shown in dashed lines). The various high and low positions afford multiple features advantageous for the intake of diverse food products. For example, the high ramp position  116   H  is preferred for the intake of various breaded products, which preferably ride down the decline of the high ramp  116   H , to level out on the main level section  114 . The low ramp position  116   L  is preferred for battered products, which are preferably dropped into the oil bath (eg., a given oil level indicated as  118 ) before eventually being fished out and elevated up the incline of the low ramp  116   L , to climb to the plane of the main level section. In use, the food product is kept submerged on the main conveyor  110  by a submerger conveyor (not shown, but see FIGS.  1  or  2  for illustration of a submerger conveyor).  
         [0052]    The fryer  100  defines a main cooking channel  122 . The cooking channel  122  is filled with cooking oil (eg.,  118 ) that is heated by heat exchangers  124  (that will be more particularly described below in connection with FIG. 9 a ). The cooking channel  122  opens up into an inboard intake-end well  126  which serves for, among other purposes, sediment removal. The inboard intake-end well  126  is set apart from an outboard intake-end well  128  by a partition  130 . The partition  130  is distanced from the pivot axis  132  of the main food conveyor  110 &#39;s ramp section  116  such that the ramp section  116  can flap among the extreme high and low positions  116   H  and  116   L  without swiping into the partition  130 .  
         [0053]    The cooking channel  122  has a bottom wall  134  which includes a level section  134   1  on which the return run  110   2  of the main food conveyor  10  scrapes. The return run  110   2  transports sediment right to left in FIG. 4 a,  or towards the sediment-removal well(s)  126 / 128 . The cooking channel  122  bottom wall  134  further includes a fixed decline section  134   2  that slopes down into the depths of the inboard sediment well  126 . When the ramp section  116   L  is in its low position, the return run scrapes  110   2  along this decline section  134   2 . At the end of the decline section  134   2 , the return run  110   2  ejects its sediment load into the inboard sediment well  126 . The heavier-than-oil content of the sediment load is free to drift down onto an inboard flight conveyor  136 . FIG. 4 b  shows that the inboard flight conveyor  136  has a scrape run  136   1  scraping over a bottom  142  for the inboard well  126 . The scrape run  136   1  of the inboard flight conveyor  136  pushes its load into an inboard sump  144 .  
         [0054]    The construction and operative principles of flight conveyors are more particularly disclosed by commonly-owned, commonly-invented U.S. Pat. No. 5,937,744—Nothum et al., which is incorporated herein by this reference to it.  
         [0055]    The fryer  100  includes a cooking oil system  140  as follows. The cooking oil  118  is in continuous circulation not only by eddying within the cooking channel  122 , but also by being suctioned out through a drain in the sump  144  by a pump  146 , which discharges to a filter  148 . That way, sediment in the cooking oil  118  can be strained and/or filtered out. After filtration, the cooking oil  118  is re-circulated back into the fryer  100   
         [0056]    An inventive aspect of this fryer  100  relates to the intake-end, outboard sediment well  128 . With the fryer set up in the high ramp  116   H  configuration, the fryer  100  is further modified by the temporary installation of a convertible incline panel  150 . The convertible incline panel  150  is shaped and arranged to allow quick connection into its installed position as shown in FIG. 4 a,  as well as quick disconnection and removal to a non-use, storage position (not shown). In the use or installed position, the convertible incline panel  150  provides a bottom wall for the conveyor&#39;s return run  110   2  to scrape across. This allows the return run  110   2  to transport sediment and oil for ejection into the outboard sediment-removal well  128 .  
         [0057]    Certainly the heavier-than-oil content of the sediment load is thus ejected into the outboard sediment well  128 . Indeed, the entire sediment load is likely ejected into the outboard sediment well  128 . The outboard sediment well  128  affords a better chance of filtering or skimming out suspended or floating sediment particles because the partition  130  creates a barrier preventing re-entry into the cooking channel  122  except by a route through the filter  148 . Like the inboard sediment well  126 , the outboard sediment well  128  has its own flight conveyor  152 . FIG. 4 b  shows that the outboard flight conveyor  152  has a scrape run  152   1  scraping over a bottom  156  for the outboard sediment well  128 . The outboard scrape run  152   1  pushes its load into an outboard sump  158 . The outboard sump  158  has a drain connected to the pump  146  which again discharges to the filter facility  148  for filtration of the cooking oil  118 . After filtration, the cooking oil  118  is re-circulated back into the fryer  100  where it can get into the cooking channel  122 .  
         [0058]    The foregoing provides advantages in extending the use life of the cooking oil  118  by enhancing the ability to more cleanly filter the cooking oil. Lessening the cooking oil&#39;s sediment load as well its residence time in the cooking channel  122  lengthens the use life of a given batch of cooking oil  118 . Extending the use life of a given batch of cooking oil extends the run-time of the fryer  100  between episodes of down-time when the cooking oil  118  must be changed out.  
         [0059]    [0059]FIG. 5 shows improvements for the inventive fryer  100 ′. These improvements relates to a pair of opposite flanking overflow gutters  153 . These gutters flank  153  the cooking channel  122  near the intake end of the fryer  100 ′ for only that much of the main conveyor  110  which comprises the ramp section  116   L . More generally, the gutters  153  extend flanking the cooking channel  122  from terminations in the outboard sediment well  128  to origins somewhere approximately near the pivot axis  130  for the ramp section  116   L . The overflow gutters  153  are especially advantageous when the ramp section  116   L  is configured in the low position, as for the intake of battered products (not shown) which are simply plunged into the oil bath at the intake end of the cooking channel  122 . Experience teaches that battered food product dropped into the oil bath this way loses some of its batter coating in free floating globules (not shown). Such globules coalesce into rafts “R” that build up along the flanking sides of the ascending ramp section  116   L  where it changes into main level section  114 . In FIG. 5, such rafts are indicated as “R.”  
         [0060]    In accordance with the improvements of FIG. 5, the broken away globules are allowed escape or overflow into the flanking gutters  153 . The gutters  153  are provided with flight conveyors  154  that convey and deposit the spillover globules or whatever in the direction of arrows  155  into the outboard sediment well  128 . The outboard flight conveyor  152  and/or the suction through the outboard sump  158  are cooperatively relied on to motivate these floating globules or whatever spillover may come into the gutters  153  and outboard well  128 , in the direction of arrows  157 . Once the globules or whatever sediment and other extraneous matter is moved to the sump  128 , it and all the oil along with are processed through the filtration system (although not shown in FIG. 5, see FIG. 4 a  and the filtration system  148  and the description of it given previously above). The foregoing arrangement of spillover gutters  153  in combination with the outboard sediment well  128  and sump  158  cooperatively deters or eliminates the build up of such rafts “R,” and better manages the problem of unwanted extraneous matter or debris in the cooking channel  122 .  
         [0061]    To accomplish the foregoing, the interior walls  159  of the gutters  153  rise up and terminate at preferably the same elevation as the upper termination of the partition  130  separating the outboard and inboard sediment wells  128  and  126 , respectively (although this common elevation and the distinction that is lower than the rest of the walls enclosing the oil bath is not directly discernible given the plan view of FIG. 5). The inboard sediment well  126 , although mostly hidden from view and thus shown by hidden lines, can be reckoned because it is serviced by the inboard flight conveyor  136  and inboard sump  144 .  
         [0062]    [0062]FIG. 9 a  is directed to a further improvement in the inventive fryer  100 . By way of background, FIG. 7 shows an arrangement  162  of rectangular heat exchanger tubes  124  in a fryer cooking channel  122 . FIG. 6 is a birds-eye detail view of a typical wire mesh conveyor belt  120 . In use, the wire mesh belt  120  is preferably formed into an endless conveyor. As shown by FIG. 8, the belt conveyor as a main food-carrying run  110   1  that scrapes on the upper broad sides  124   1  presented by the tubes  124 . The belt conveyor also has a lower or sediment-transporting run  110   2  which passes underneath the tubes  124 , preferably as scraping along the bottom wall  134  of the cooking channel  122 .  
         [0063]    [0063]FIG. 6 shows that the wire mesh belt  120  preferred for the fryer preferably has these characteristics. The axial dimension or length of the belt is produced by a series of successive wires  164 . Each wire  164  extends the lateral width or span of the belt, as from one side edge to the other. Any given wire  164  is formed with a series of U-shaped loops, and such a given wire  164  is woven around its preceding neighbor in an interwoven pattern as shown. Likewise, the given wire  164 &#39;s trailing neighbor wire is comparably formed with corresponding U-shaped loops and is woven around the given wire  164  in the same fashion. The weave pattern is carried on to the extent necessary to produce a belt in the widths and lengths desired.  
         [0064]    These woven wire belts  120  are desirable for many reasons. Among them, these belts  120  provide greater than 85% open area. This allows fairly unrestricted cooking oil contact with the food product. It also facilitates wash down and inspection. They are lightweight and don&#39;t demand much drive power. Also, they turn tight circumferences around small transfer rollers to ensure gentle handling and smooth transfer of various products. These belts  120  can be produced in about any width, with commercially available sources providing standardized widths available off-the-shelf as anywhere between about four inches (0.1 m) and twelve feet (3.7 m). Needless to say, these belts  120  can be produced in indefinitely long lengths.  
         [0065]    However, one aspect of these belts  120  is that they show an axially extending seam  166  at given intervals across the lateral width or span of the belt  120 . These seams  166  are typically oriented internally. These seams  166  represent the continuous string of intersections of the weave of a given wire  164  with its preceding neighbor (eg., the trailing intersection being characterized by the weave of the trailing neighbor with the given wire  164 ).  
         [0066]    [0066]FIG. 8 is a transverse section view of the FIG. 7 prototype arrangement  162  of rectangular heat exchange tubes  124  in the cooking channel  122 . The tubes  124  are disposed to present one of their broad sides  124   1  to the food-carrying run  110   1 . That is, the food-carrying run  110   1  scrapes across their upper broad sides  124   1 . The return run  110   2  scrapes on the bottom wall  134  of the cooking channel  122  and passes closely underneath the heat exchanger tubes  124 . The hoped-for result was to allow for a more shallow cooking oil depth in the cooking channel  122 .  
         [0067]    What was found was this:—that the FIGS. 7, 8 arrangement  162  did not provide a satisfactory heat load. Simply, the cooking oil often got too cold. The food product could not be run through at desired rates of throughput (as measured in pounds per hour). In use, needless to say, the cooking product draws heat from the hot cooking oil, which withdrawn-heat is refurnished by the heat exchanger tubes  124 . The rate at which the heat exchanger tubes  124  can refurnish the withdrawn heat is dependent on several factors. Among others, the rate at which the heat exchanger tubes  124  can refurnish the withdrawn heat is proportional to surface area of the tubes  124 .  
         [0068]    In other words, the heat duty of the fryer or fryer system can be thought of as a simple power cycle. The tubes  124  supply heat power to the cooking oil. The cooking product depletes the oil of its heat. The tubes  124  re-supply the heat-depleted cooking oil with more heat, which is continually being withdrawn by the cooking product. Accordingly, if the heat exchangers  124  can only manage to input heat power into the system at a trickle, only a trickle of food product can be adequately cooked. On the other hand, if the heat exchangers  124  can flood the system with heat power, then the system can adequately cook much higher throughput rates of food product.  
         [0069]    It was also discovered that, with the FIGS.  7 / 8  arrangement  162 , the belt seams  166  tended to fill the gaps  168  between the tubes  124 . This hindered sediment removal in various ways, including that it did not allow sediment much clearance to fall through to the sediment-transporting run  110   2 . In sum, it was noticed that the heat-exchange and/or sediment-removal qualities of this arrangement  162  system invited improvement.  
         [0070]    The FIG. 8 proto-type arrangement  162  preceded the inventive arrangement  170  shown by FIG. 9 a.  In FIG. 9 a,  the rectangular tubes  124  are arranged side by side—that is, broad side  124   1 —next to broad side  124   1 —with gaps  172  other than the gaps  168  at the seams  166  to increase heat transfer surface area. The tubes  124  are hence stood on their narrow sides  124   2 . The upper narrow sides  124   2  are arranged on a uniform level to present a supporting or scrape surface for the food-carrying run  110   1  of the main belt. By way of non-limiting example, the FIG. 9 a  arrangement  170  shows that every third and fourth tube are spaced by a gap  168  sufficient to accommodate the belt seam  166  traveling therethrough. The other gaps  172  as between the first and second tubes and the second and third tubes allow clearance for the fall through of sediment. The sediment can be transported out of the cooking channel  122  by the sediment-transporting run  110   2  below, which preferably discharges into one of the two versions of sediment wells  126 / 128  as shown by FIG. 4 a  (or FIG. 4 b ).  
         [0071]    Hence, FIG. 9 a  shows an improved heat exchanger arrangement  170 . The total number of tubes  124  included is increased, at least in this example, threefold. The heat transfer surface area is likewise increased three fold. Additional gaps  172  are provided other than those gaps  168  giving clearance to the belt seams  166 . The other gaps  172  not only allow clearance for falling sediment but also, improve cooking oil swirling and eddying across the tube broad faces  124   1 . The improved cooking-oil swirling or eddying across the tube broad faces  124   1  affords more efficient heat exchange by improving the heat transfer factor or coefficient. At the same time, the FIG. 9 a  arrangement  170  affords a significantly shallow cooking channel to minimize the quantity of cooking oil needed to charge the fryer.  
         [0072]    [0072]FIG. 9 b  shows an alternate version  171  of the FIG. 9 a  arrangement  170 . In FIG. 9 b,  the heat exchanger tubes  174  are more compact versions of the tubes  124  in FIG. 9 a.  Nevertheless, the tubes  174  are arranged to preserve the belt-seam gaps  168  for clearance of the belt seams  166  as they travel axially therethrough. Also, the tubes  174  are arranged to provide at least one or more other gaps  172  intermediate the belt-seam gaps  168  to facilitate downward communication of sediment from the food-carrying run  110   1  to the sediment transporting run  110   2  below.  
         [0073]    The invention having been disclosed in connection with the foregoing variations and examples, additional variations will now be apparent to persons skilled in the art. The invention is not intended to be limited to the variations specifically mentioned, and accordingly reference should be made to the appended claims rather than the foregoing discussion of preferred examples, to assess the scope of the invention in which exclusive rights are claimed.