Abstract:
A conveyor belt system provides a continuous flat support surface for a food item that moves the food item through a food preparation device. The conveyor belt system includes a conveyor belt having a plurality of spaced apart rods and a plurality of slats that are removably attached to the conveyor belt with a snap on mechanism. The slats are easily assembled and provide enhanced field service and/or replacement capability.

Description:
FIELD OF THE INVENTION 
       [0001]    The disclosure is directed to a conveyor belt for conveying food items into a heated food preparation chamber, such as a toaster. In particular, the disclosure is directed to a snap on slat for a conveyor belt that minimizes costs, simplifies field maintenance, and simplifies manufacturing and assembly of a conveyor belt including the snap on slat. 
       BACKGROUND 
       [0002]    In the food preparation industry often food items are prepared, at least partially, by placing the food items on a conveyor belt that transports the food items into a food preparation device, such as a toaster. Such toasters include a heated platen and a slowly rotating conveyor belt. The conveyor belt holds the food item in close proximity to the platen while the conveyor belt simultaneously transports the food item through the preparation device. The length of time the food item is exposed to the heated platen may vary based on the length of the platen and the speed of the conveyor belt. Such toasters may process food items continuously as opposed to household toasters that process food items in batch mode, such as two or four pieces of bread at a time. Conveyor toasters are ill-suited for consumer use because of their size, manufacturing cost, power requirements, and the time required to pre-heat the platen to operating temperature. However, conveyor toasters are preferred by restaurants and food services that require high-volume through-put and consistent heating/toasting. 
         [0003]    Conveyor toasters generally include a wire conveyor belt. Wire conveyor belts are ideal for material handling, cooking, icing, slicing breading, cooling, filling, inspecting, and packing of products like breads, rolls, buns, donuts, confections, cakes, pies, pastries, meat, seafood, poultry, and other processed foods. The simple, open design of wire conveyor belts provides efficient operation with minimum maintenance and easy cleanup to meet sanitation requirements. One such known wire conveyor belt is illustrated in  FIGS. 1 and 2 . The wire conveyor belt  10  may include a plurality of spaced metal rods  16  interconnected by coupling “hook” and “loop” connection elements  18 ,  20  formed at the rod ends of adjacent metal rods  16 . The rods  16  may support a food item and the rods  16  may hold the components of the belt together by way of the interconnected hook and loop connection elements  18 ,  20 . 
         [0004]    One known conveyor belt, for example, is the wire conveyor belt disclosed in U.S. Pat. No. 7,987,972, which is herein incorporated by reference in its entirety. The wire conveyor belt provides a flat support surface, but is relatively expensive to produce and is cumbersome to assemble and relatively difficult to repair or replace in the field. The plates are attached to a first spaced rod at a first end and to a second spaced rod that is adjacent to the first spaced rod at the second end. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]      FIG. 1  is a top view of a segment of a conventional wire conveyor belt. 
           [0006]      FIG. 2  is a side perspective view of the wire conveyor belt segment shown in  FIG. 1 . 
           [0007]      FIG. 3  is a partial perspective view of a conveyor belt system constructed in accordance with the disclosure, the system includes a conveyor belt and a plurality of slats removably coupled to the conveyor belt. 
           [0008]      FIG. 4  is a bottom perspective view of the conveyor belt system of  FIG. 3 . 
           [0009]      FIG. 5  is a perspective view of one embodiment of a slat of the conveyor belt system of  FIG. 3 . 
           [0010]      FIG. 6  is a perspective view of a horizontal toaster including the conveyor belt system of  FIG. 3 . 
           [0011]      FIG. 7  is a perspective view of a vertical toaster having an angled product feed chute and including the conveyor belt system of  FIG. 3 . 
           [0012]      FIG. 8  is a perspective view of a vertical toaster having a vertical product feed chute and including the conveyor belt system of  FIG. 3 . 
           [0013]      FIG. 9  is a perspective view of the vertical toaster of  FIG. 8  with a cover removed revealing the conveyor belt system of  FIG. 3 . 
           [0014]      FIG. 10  is a perspective view of another embodiment of a slat of the conveyor belt system of  FIG. 3 . 
           [0015]      FIG. 11  is a perspective view of yet another embodiment of a slat of the conveyor belt system of  FIG. 3   
       
    
    
     DETAILED DESCRIPTION 
       [0016]    A conveyor belt system with snap on slats supports a food product and moves the food product through a food preparation device, such as a toaster or oven, without substantially marking or pinching the food product. Additionally, the conveyor belt system with snap on slats eases assembly of the conveyor belt system while also providing the ability to replace or repair individual slats in the field without the need for specialized tools. Individual slats may be made of any material that is durable enough to withstand temperatures within the food preparation device. Examples of slat materials include metals, such as copper, iron, aluminum, and nickel, and/or metal alloys such as steel, brass, and bronze. Stainless steel is one preferred material for manufacturing the slats and AISI T-304 is an exemplary type of stainless steel that may be preferred. 
         [0017]    Turning now to  FIG. 3 , a conveyor belt system  100  includes a wire conveyor belt assembly  110  and a drive mechanism, such as a drive sprocket  111 . The wire conveyor belt assembly  110  includes a wire conveyor belt  112  and a plurality of removable slats  140 . The plurality of removable slats  140  form a continuous flat support surface for conveying an item, particularly a food item through a food preparation device, such as a toaster or oven. 
         [0018]    The conveyor belt  112  comprises a plurality of spaced metal rods  116  disposed in succession and transversely with respect to a direction of conveyance. The plurality of spaced rods  116  form the wire conveyor belt  112  which serves, in part, as a scaffolding for the plurality of removable slats  140 . The wire conveyor belt  112  also interacts with the drive mechanism, to move the rods  116  and the removable slats  140  through the food preparation device. Other scaffoldings capable of receiving removable slats  140  may also be used. In the embodiment illustrated in  FIGS. 3 and 4 , each rod  116  has two end portions  121  and a supporting rod portion  116   a  extending therebetween. Each end portion  121  includes a terminal hook connection element  118  that protrudes in a first direction, curves, and extends in a direction substantially opposite to the first direction for a predetermined distance. Each rod  116  also has two loop connection elements  120 , which are formed in the rods  116  themselves. The hook connection elements  118  are interconnected/coupled to the loop connection elements  120  of an adjacent spaced metal rod  116  to interlock adjacent metal rods  116 . The hook connection elements  118  and the loop connection elements  120  interact to allow adjacent rods  116  to pivot about an axis of the rod  116 , for example while turning around the sprocket  111 , while securing adjacent rods  116  to one another. 
         [0019]    The conveyor belt assembly  110  includes the plurality of spaced metal rods  116  and the plurality of substantially flat slats  140 . The slats  140  form a top side, or support surface,  115  and a bottom side  117 . The top side  115  forms a flat support surface for conveying the food product, and the bottom side  117  forms a platform that is at least partially supported by the rods  116 . 
         [0020]    The support surface  115  is formed by the plurality of slats  140  which are coupled to selected rods  116  of the plurality of spaced metal rods  116 . The slats  140  are secured at least partially between a first spaced rod  116  of the plurality of spaced rods  116  and a second spaced rod  116 , the second spaced rod  116  being separated from the first spaced rod and supporting the slat  140  so that a leading edge  142  and a trailing edge  143  are unsecured and free of any attachment, but supported along the bottom  117 , thereby providing a joint that allows adjacent slats  140  to partially rotate relative to one another at the leading edge of each slat  140  and at the trailing edge of each slat  140 , for example, when the slats  140  turn around the sprocket  111 . 
         [0021]    Turning now to  FIG. 5 , each slat  140  includes a flat base portion  141  having a leading edge  142  and a trailing edge  143  relative to the direction of conveyance. Each slat  140  also includes a snap on connection element  145  at each end of the flat base portion  141 . The snap on connection element  145  extends substantially perpendicular to the flat base portion  141  and away from the top surface  115 . The snap on connection element  145  removably secures the slat  140  to the conveyor belt  112  by sliding between two adjacent rods  116  and expanding after passing the rods  116  so that the slat  140  may be separated from the conveyor belt  112  by applying a force in a direction opposite the snap on connection element  145 , for example, by pulling the slat  140  away from the conveyor belt  112 . The snap on connection element  145  leaves the leading edge  142  and the trailing edge  143  free of any attachment either with adjacent slats  140  or with the rods  116 , so that adjacent slats  140  may partially rotate relative to one another, for example when rotating around the sprocket  111  ( FIG. 3 ). 
         [0022]    The snap on connection element  145  may include two spaced apart legs  151  that are separated from one another by a gap  147 . Each leg  145  may include an angled leading surface  153  and a notch  155 . The angled leading surface  153  divides the leg  151  into a narrower portion distal to the flat base portion  141  and wider portion proximate to the flat base portion  141 . A peak  157  may be formed between the angled leading surface  153  and the notch  155 , the peak  157  defining the widest location of the leg  151 . The notch  155  may be sized and shaped to receive one rod  116  between the peak  157  and the flat base portion  141 . For example, the notch  155  may include a curved surface that forms an arc of a circle, to complement the outer surfaces of the cylindrical rods  116 . The gap  147  allows the legs  151  to be displaced towards one another when the slat  140  is being secured to the conveyor belt  112 . The gap  147  may include a radiused top  159  that disperses material stress, especially when the two legs  151  are displaced towards one another during installation of the removable slat  140 . 
         [0023]    As illustrated in  FIG. 4 , when the slat  140  is secured to the conveyor belt  112 , the legs  151  extend between adjacent rods  116 . One rod  116  being seated within the notch  155  of a first leg  151  (e.g., a front leg) and another rod  116  being seated within the notch  155  of a second leg  151  (e.g., a back leg). The peak  157  prevents the legs  151  from backing out of the gap between the rods  116 . To remove the slat  140 , a force may be applied in a direction away from the rods  116  (e.g., away from the rods  116 ), which will cause the legs  151  to deform inwardly, towards one another, due to the curved surface of the notch  155  leading up to the peak  157 . As the force increases, the peak  157  will eventually move far enough towards the other leg  151  that the peak  157  will be able to pass by the rod  116 , thereby allowing the slat  140  to be removed from the conveyor belt  112 . Alternatively, a force may be applied directly to the legs  151 , pinching the distal ends of the angled leading surfaces  153  towards one another, causing the legs  151  to move towards one another to allow the peak  157  to clear the rod  116 , before separating the removable slat  140  from the conveyor belt  112 . 
         [0024]    Conversely, to secure the removable slat  140  to the conveyor belt  112 , the angled leading surfaces  153  of the legs  151  may be placed into a gap between two rods  116 . A force may be applied towards the conveyor belt  112 , which causes the legs  151  to deform inwardly, towards one another, due to the slope of the angled leading surfaces  153 . Eventually, the legs  151  will deform sufficiently to allow the peak  157  to pass over the rod  116 . Once the peak  157  is clear of the rod  116 , the legs  151  will return to their original position, expanding away from one another, which allows the rod  116  to seat within the notch  155 . The same rod  116  may also seat within a notch  155  of an adjacent slat  140 . Alternatively, a force may be applied directly to the legs  151 , proximate the distal ends of the angled leading surfaces  153 , causing the legs  151  to move towards one another to allow the peak  157  to clear the rod  116 , before moving the slat  140  towards the conveyor belt  112 . Once the legs  151  are sufficiently deformed, the legs  151  may be moved into a gap between adjacent rods  116 , and once the peak  157  is clear of the rod  116 , the legs  151  may be allowed to expand away from one another into their original positions, which allows the rod  116  to seat in the notch  155 . 
         [0025]    The removable slats  140  are preferably formed from a metal material, such as stainless steel, or any other suitable material. For example, the removable slats  140  may be manufactured from an extrudable material including, but not limited to, extrudable metals, extrudable polymers, and extrudable ceramics. Exemplary extrudable metals include, but are not limited to, aluminum, brass, copper, magnesium, and steel. Aluminum alloys such as hard coated anodized aluminum, for example AA 6063-T6, are preferred. Exemplary extrudable plastics include, but are not limited to, polyvinylchlorides, polyethylenes, polypropylenes, acetals, acrylics, nylons (polyamides), polystyrene, acrylonitrile butadiene styrenes, and polycarbonates. 
         [0026]    In the conveyor belt system  100  of  FIG. 3 , the top surfaces  115  of the removable slats  140  are generally smooth. The top surfaces may, however, be corrugated or textured to better grip an item. In other embodiments, the top surfaces of the removable slats  140  may include gripping features to retain an item while the item is transported to facilitate the frictional engagement of the food product. The roughness of the surface of the removable slats  140  in one embodiment may be provided by shot peening the surfaces of the slats  140  using a predetermined shot size, as is disclosed in U.S. Patent Publication No. 2010/0275789, which is herein incorporated by reference in its entirety. Alternatively, the surface of the removable slat  140  may have gripping features such as an abrasive coating, dimples, furrows, or protrusions that would be strong enough to grip the food product, but not so abrasive that the gripping features rip, tear, or mark the food product. 
         [0027]    The conveyor belt system  100  may be used in a horizontal toaster  700  as illustrated in  FIG. 6 , an angled toaster  800  as illustrated in  FIG. 7 , or a vertical toaster  901  as illustrated in  FIG. 8 . 
         [0028]    Existing conveyor toasters usually include a product feed where the product is inserted into an opening of the toaster. For example, in the angled toaster  800  in  FIG. 7 , the product travels down an angled shoot  801 , usually angled at about 45 degrees, and is received by a conveyor belt  110  (not shown in  FIG. 7 ). The conveyor belt assembly  110  receives the food product and urges it through an opening between the conveyor belt and a heated platen. In some conveyor toasters, the food product is compressed through this opening between the platen and the conveyor belt, also called a compressive gap, to process the food product. 
         [0029]    The disclosed conveyor belt system  100  may be used in a vertical toaster  901 , as illustrated in  FIG. 8 . The vertical toaster  901 , an example of which is disclosed in U.S. Patent Publication No. 2010/02757789, has multiple removable and adjustable conveyor belts that receive a food product at an opening at the top of the toaster. As illustrated in  FIG. 9 , a vertical conveyor belt system  900  may include a guide structure  902  that runs the full length of the conveyor belt  112 . In one embodiment, the conveyor belt system  900  may include a guide structure  902  on both ends of the conveyor belt assembly  110 . The guide bar  904  may be fixed to a bracket  905  that attaches the guide bar  904  to the conveyor belt housing  906 . The vertical toaster  901  includes a heating element (not shown), such as a heated platen, for example. 
         [0030]    Turning now to  FIG. 10 , an alternate embodiment of a slat  240  is illustrated. Each slat  240  includes a flat base portion  241  having a leading edge  242  and a trailing edge  243  relative to the direction of conveyance. Each slat  240  also includes a snap on connection element  245  at each end of the flat base portion  241 . The snap on connection element  245  extends substantially perpendicular to the flat base portion  241  and away from the top surface  215 . The snap on connection element  245  removably secures the slat  240  to the conveyor belt  112  by sliding between two adjacent rods  116  and expanding after passing the rods  116  so that the slat  240  may be separated from the conveyor belt  112  by applying a force in a direction opposite the snap on connection element  245 , for example, by pulling the slat  240  away from the conveyor belt  112 . The snap on connection element  245  leaves the leading edge  242  and the trailing edge  243  free of any attachment either with adjacent slats  240  or with the rods  116 , so that adjacent slats  240  may partially rotate relative to one another, for example when rotating around the sprocket  111  ( FIG. 3 ). 
         [0031]    The snap on connection element  245  may include two spaced apart legs  251   a ,  251   b  that are separated from one another by a gap  247 . Each leg  251   a,    251   b  may include an angled leading surface  253  and a notch  255 . The angled leading surface  253  divides the legs  251   a,    251   b  into a narrower portion distal to the flat base portion  241  and wider portion proximate to the flat base portion  241 . A peak  257  may be formed between the angled leading surface  253  and the notch  255 , the peak  257  defining the widest location of each leg  251   a,    251   b.  The notch  255  may be sized and shaped to receive one rod  116  between the peak  257  and the flat base portion  241 . For example, the notch  255  may include a curved surface that forms an arc of a circle, to complement the outer surfaces of the cylindrical rods  116 . The gap  247  allows the legs  251   a,    251   b  to be displaced towards one another when the slat  240  is being secured to the conveyor belt  112 . The gap  247  may include a radiused top  259  that disperses material stress, especially when the two legs  251   a,    251   b  are displaced towards one another during installation of the removable slat  240 . 
         [0032]    In the embodiment illustrated in  FIG. 10 , a first leg  251   a  is offset in a lateral direction from a second leg  251   b.  Offsetting the legs  251   a,    251   b  in the width direction from one another can advantageously enhance clearance between legs  251   a,    251   b  on adjacent slats  240 , thereby preventing interference between adjacent legs  251   a,    251   b.    
         [0033]    Turning now to  FIG. 11 , yet another alternate embodiment of a slat  340  is illustrated. Each slat  340  includes a flat base portion  341  having a leading edge  342  and a trailing edge  343  relative to the direction of conveyance. Each slat  340  also includes a snap on connection element  345  at each end of the flat base portion  341 . The snap on connection element  345  extends substantially perpendicular to the flat base portion  341  and away from the top surface  315 . The snap on connection element  345  removably secures the slat  340  to the conveyor belt  112  by sliding between two adjacent rods  116  and expanding after passing the rods  116  so that the slat  340  may be separated from the conveyor belt  112  by applying a force in a direction opposite the snap on connection element  345 , for example, by pulling the slat  340  away from the conveyor belt  112 . The snap on connection element  345  leaves the leading edge  342  and the trailing edge  343  free of any attachment either with adjacent slats  340  or with the rods  116 , so that adjacent slats  340  may partially rotate relative to one another, for example when rotating around the sprocket  111  ( FIG. 3 ). 
         [0034]    The snap on connection element  345  may include two spaced apart legs  351   a ,  351   b  that are separated from one another by a gap  347 , which is not clearly illustrated in  FIG. 11  because of the perspective nature of the figure, but the gap  347  is consistent with the gap  247  shown in  FIG. 10  and the gap  147  shown in  FIGS. 3 and 5 . Each leg  351   a ,  351   b  may include an angled leading surface  353  and a notch  355 . The angled leading surface  353  divides the legs  351   a,    351   b  into a narrower portion distal to the flat base portion  341  and wider portion proximate to the flat base portion  341 . A peak  357  may be formed between the angled leading surface  353  and the notch  355 , the peak  357  defining the widest location of each leg  351   a,    351   b.  The notch  355  may be sized and shaped to receive one rod  116  between the peak  357  and the flat base portion  341 . For example, the notch  355  may include a curved surface that forms an arc of a circle, to complement the outer surfaces of the cylindrical rods  116 . The gap  347  allows the legs  351   a,    351   b  to be displaced towards one another when the slat  340  is being secured to the conveyor belt  112 . The gap  347  may include a radiused top  359  that disperses material stress, especially when the two legs  351   a,    351   b  are displaced towards one another during installation of the removable slat  340 . 
         [0035]    In the embodiment illustrated in  FIG. 11 , a first leg  351   a  is offset in a lateral direction from a second leg  351   b.  Offsetting the legs  351   a,    351   b  in the width direction from one another can advantageously enhance clearance between legs  351   a,    351   b  on adjacent slats  340 , thereby preventing interference between adjacent legs  351   a,    351   b.    
         [0036]    The embodiment illustrated in  FIG. 11  differs from that illustrated in  FIG. 10  in that the offset legs  351   a,    351   b  differ at opposite ends of the slat  340 . For example, in  FIG. 11 , the first leg  351   a  at a first end  398  of the slat  340 , which is generally adjacent the leading edge  342 , is offset towards a second end  399  of the slat  340 . However, the corresponding leg  351   a  at the second end  399  of the slat  340  is not offset. At the second end  399  of the slat  340  it is the second leg  351   b,  which is generally adjacent to the trailing edge  343 , that is offset. Thus, the offset legs  351   a,    351   b  are arranged in a staggered configuration as opposed to the symmetrical configuration of  FIG. 10  in which both legs  351   a  (or both legs  351   b ) are offset. 
         [0037]    In accordance with a preferred embodiment of the conveyor belt system, the compression gap can be adjusted according to varying sizes of food product. In one embodiment, the conveyor belt can be adjusted with respect to the reactive surface as illustrated and explained in U.S. Patent Publication No. 2010/0275789. 
         [0038]    While the present invention has been described with respect to a particular embodiment of the present invention, this is by way of illustration for purposes of disclosure rather than to confine the invention to any specific arrangement as there are various alterations, changes, deviations, eliminations, substitutions, omissions and departures which may be made in the particular embodiment shown and described without departing from the scope of the claims.