Patent Publication Number: US-11383934-B2

Title: Gap filler for reciprocating floor slat conveyor

Description:
TECHNICAL FIELD 
     This design relates to reciprocating floor slat conveyors. 
     BACKGROUND 
     Reciprocating floor slat conveyors are well-known. They consist of a series of side-by-side floor slats that are all moved in one direction at the same time. This moves or conveys a load that rests on the floor slats. Then, a lesser number of floor slats is moved in the opposite direction, sliding underneath the load. This is commonly done in sets of three, or in other words, one third of the slats are moved in the opposite direction, in sequence, until all are returned to their initial position. Moving a lesser number of slats during the return sufficiently reduces friction between the slats and the load above, such that the load holds its position during the return. Then, the slats are moved again, all at the same time, to further carry the load, and so forth, with the sequence just described being repeated until the load is moved off the reciprocating floor slat conveyor. Systems of this kind are often installed in trailers for hauling and unloading bulk materials, although there are also many other kinds of applications, including stationary applications. 
     The reciprocating floor slats are commonly made from extruded aluminum. However, there is a need and market for steel floor slats. Steel is a better material for floor slats compared to aluminum and would be better for use in the solid waste industry. Regardless of the material that is used to manufacture the slats (i.e., aluminum vs. steel), the space between individual slats (that are side-by-side each other in the installed conveyor) needs to be sealed. In the solid waste industry, for example, where aluminum slats have been used, the seals between slats can be the first thing to fail. The type of seal used for an aluminum slat does not translate for use in a steel slat for reasons relating to differences between aluminum and steel. 
     The design disclosed here was created to fill the elongated space or “gap” between steel floor slats. The design solves a problem in that it enables the sealing of the elongated gap that is created between individual, roll-formed steel slats. Roll-forming is a different process relative to making extrusions. 
     Floor slats that are extruded from aluminum can be made with nonuniform wall thicknesses that include elongated seal-holding grooves or recesses. These grooves or recesses can hold a gap-filling seal in place between aluminum slats that are arranged side-by-side across the width of the reciprocating floor conveyor. 
     Referring to  FIG. 22 , as an example, which is labeled and acknowledged to be “prior art,” a conventional aluminum slat (shown in cross-sectional profile) is indicated at  1 . The slat  1  rests upon a bearing member  2 . The bearing member  2  is supported by a square subdeck member  3 . The gap-filling seal is indicated at  4 . As can be seen in this Figure, the seal  4  has an enlarged portion  5  that is captured by a recess  6  in the aluminum slat  1 . A split portion  7  of the seal fills the gap (indicated generally by arrow  8 ), which prevents material from working through the gaps between individual slats as they move back-and-forth during operation of the conveyor (bear in mind that all of these components are elongated and extend lengthwise into the page). 
     Aluminum can be extruded to the slat form illustrated in  FIG. 22  with the seal-capturing recess  6 . This is not workable for steel floor stats that are roll-formed from harder and thicker steel alloys, because roll-forming has practical limitations that make it difficult to mimic what can be done (in terms of cross-sectional profile) in comparison to extruding aluminum. 
     A steel floor slat (that is roll-formed) is therefore likely to have a less complicated cross-sectional profile, relative to an extruded aluminum floor slat, with the steel slat&#39;s top and side surfaces having the same thickness throughout, resulting from a single steel strip being put through a roll-forming process that bends the steel into top and side sections. This creates a design problem for sealing the gaps between steel slats because, as indicated above, unlike extruded aluminum, it is not workable to roll-form steel with the kind of seal-holding pockets or recesses (i.e., reference number  6  in  FIG. 22 ) that have been used in the past to seal gaps between aluminum floor slats in reciprocating conveyors. 
     The design disclosed here makes roll-formed steel slats practical in typical markets where reciprocating floor slat conveyors are used and offers the advantage of using more-durable steel instead of aluminum, particularly when reciprocating floor slat conveyors are built into trailers (or the like) that are used to haul and unload abrasive materials. The design enables a simple steel slat profile to work in reciprocating floor slat conveyors. 
     SUMMARY 
     For use with a reciprocating floor slat conveyor that has reciprocating floor slats that are formed from steel, a gap filler that fills the space between side-by-side slats. 
     The slats in the conveyor will have a lengthwise gap between adjacent side-by-side steel slats that enables the slats to move together, or in reciprocating fashion, according to conventional operation of the conveyor. The gap filler includes an upper portion that extends upwardly into the lengthwise gap. A lower portion of the gap filler, connected to the upper portion as a single integrated piece, is wrapped around a lower side edge of one of the side-by-side steel slats. 
     The lower portion of the gap filler is made to pinch the lower side edge or sidewall of the steel slat, in the manner described below. This enables the gap filler to be pre-installed on the roll-formed steel slat. During the assembly sequence that involves installing roll-formed steel slats side-by-side across a conveyor, the gap-filler&#39;s upper portion is initially elevated vertically relative to its final installation position, which enables the combination of steel slat and gap filler seal to be installed during the assembly of the reciprocating floor conveyor. 
     Final installation involves pushing down the gap-filler&#39;s upper portion (or, in other words, pushing the gap-filler further downward into the gap between side-by-side floor slats). When this happens, the upper portion of the gap filler (in the gap between slats) shifts to close and seal the gap. At the same time, the lower portion of the gap filler is shaped to shift into place around the lower side edge or sidewall of the steel slat, thereby holding the gap filler in position between the floor slats as they subsequently move together, or move relative to each other, according to the operation of the reciprocating floor conveyor. As is described further below, this shifting movement (caused by pushing the gap filler downward) involves the lower portion of the gap filler having an angled surface that rotates to match a surface on the inside of the sidewall of the slat when the gap filler is pushed down. This serves to hold the gap filler in position so that it seals the floor slats properly during conveyor operation. 
     Like the floor slats, the gap filler is likely to be elongated, although length of the gap filler is a variable. Near the end of the floor slat, however, the lower portion of the gap filler will be independently fastened to the floor slat, where hauled material drops off the conveyor system during the unloading process. 
     The gap filler design disclosed here makes reciprocating steel floor slats viable for other hauling markets. For example, the combination of steel slat, gap filler, and steel subdeck may enable the hauling of heavier, high-impact materials. Supporting bearings, i.e., the components that rest on the subdeck and provide a sliding surface for the steel slats above, can be extruded as single-piece bearings (in lieu of two separate bearings) that are possibly installed on the subdeck at the same time as individual steel floor slats. This may provide certain advantages for the installer. 
     The above summary will be better understood upon review of the following description which is to be read in conjunction with the illustrated details of the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings are described as follows, wherein like parts indicate like parts throughout, except where the text indicates otherwise: 
         FIG. 1  is a cross-sectional view of a series of side-by-side reciprocating floor slats; 
         FIG. 2  is an enlarged view of one floor slat of the overall floor slat configuration shown in  FIG. 1 ; 
         FIG. 3  is a cross-sectional view of a subdeck component of the floor slat configuration shown in  FIG. 1 ; 
         FIG. 4  is a cross-sectional view of floor bearing components of the floor slat configuration shown in  FIG. 1 ; 
         FIG. 5  is a cross-sectional view of a “gap filler” component of the floor slat configuration shown in  FIG. 1 ; 
         FIG. 6  is a view like  FIG. 5 , but without dimensions; 
         FIG. 7  is a cross-section view of two side-by-side reciprocating floor slats made from roll-formed steel, but with a different embodiment of floor bearing; 
         FIG. 8  is similar to  FIG. 7 , but illustrates another floor bearing embodiment; 
         FIG. 9  is similar to  FIG. 7  but shows a roll-formed steel subdeck; 
         FIG. 10  is similar to  FIG. 8  but shows a roll-formed subdeck; 
         FIG. 11  is a cross-sectional view of a single, roll-formed steel slat, and illustrates how the gap filler is attached to the slat; 
         FIG. 12  is a cross-section view that shows the initial position of the gap filler during the floor slat installation process; 
         FIG. 13  is an enlarged cross-sectional view of  FIG. 12  and shows the final position of the gap filler during the floor slat installation process; 
         FIG. 14  is a cross-sectional view that is similar to  FIG. 12 , but shows an aluminum subdeck for supporting all-steel floor slats; 
         FIG. 15  is the same view as  FIG. 14 , but shows the final position of the gap filler, similar to  FIG. 13 ; 
         FIG. 16  is a cross-sectional view similar to  FIG. 14 , but illustrates how the gap filler seals a moving floor slat to a fixed slat on the side of the conveyor; 
         FIG. 17  is the same view as  FIG. 16 , but shows the gap filler in its final position after installation; 
         FIG. 18  is an enlarged pictorial view of the end of a roll-formed steel slat, with gap filler and end cap components exploded from the steel slat; 
         FIG. 19  is a cross-sectional view showing the final installation of the components illustrated in  FIG. 18 ; 
         FIG. 20  is a cross-sectional view of a floor bearing resting on an aluminum subdeck component; 
         FIG. 21  is similar to  FIGS. 12 and 20  in that this Figure is a cross-sectional view showing a slat/gap filler combination being pushed down onto an aluminum subdeck member during a floor slat installation sequence; and 
         FIG. 22  is labeled “prior art” and is a cross-sectional view that shows how the gaps between side-by-side slats made of extruded aluminum have been sealed in the past. 
     
    
    
     DETAILED DESCRIPTION 
     Referring first to  FIG. 1 , each floor slat is generally identified by reference numeral  10 . It is envisioned that the floor slat  10  will be made of formed steel having the shape illustrated in the drawings. 
     Referring now to  FIG. 2 , each floor slat rests upon a pair of bearings  12 ,  14 , which further rest upon a subdeck component, indicated generally at  16 . As can be seen in  FIG. 1 , the floor slats are installed so that a small or narrow gap (at the position indicated by reference numeral  18 ) will exist lengthwise between the sides  20 ,  22  of the slats. This gap is filled by the component (“the gap filler”) indicated generally at  24  in  FIGS. 5 and 6 . 
     The narrow gap  18  between the floor slats is filled by an upper portion  26  of the gap filler  24 . The lower portion of the gap filler  24 , indicated generally by reference numeral  28  in  FIGS. 5 and 6 , is wrapped around a lower side edge  30  of the steel floor slat (see, e.g.,  FIG. 2 ). 
     Exemplary dimensions of the gap filler  24  are provided in  FIG. 5 . While these dimensions may vary, it is envisioned that they will be sized so that the lower portion  28  of the gap filler can snap-fit onto the lower side edge  30  of the steel floor slat. This would allow the gap filler to be preinstalled at the place of floor slat manufacture and then shipped, installed, to the end user. 
     When the floor slats  10  are installed in the manner illustrated in  FIG. 1 , the upper portion  26  of the gap filler  24  vertically fills gap  18  and is captured in place. It is envisioned that the gap filler  24  can be made from different materials ranging from metal (aluminum, for example) or high-density plastic. This is an ongoing matter of development and test. High temperature UHMW plastic may be used for some hauling applications like asphalt, for example. 
     Referring now to  FIGS. 7 and 8 , the subdeck component  16  previously described is illustrated as an aluminum extrusion. As an alternative, the subdeck component  16  could be made from rolled steel, which is illustrated at  32  in  FIGS. 9 and 10 . 
     In all the embodiments shown in  FIGS. 7-10 , the pair of bearings  12 ,  14  (previously illustrated in  FIG. 2 ) is replaced by a single bearing illustrated at  34 . The single bearing  34  is shown as having two versions  34 A,  34 B. According to the embodiments illustrated here, one version ( 34 A) is designed to have longitudinal grooves  36 , while the other ( 34 B) lacks these specific grooves. Both versions ( 34 A,  34 B) of the single bearing  34  have a central channel  38 . In the embodiment that illustrates the roll formed steel subdeck  32 , the central channel  38  of the bearing  34  rests on top of an upwardly projecting portion  40  of the subdeck (see  FIGS. 9 and 10 ). The bearing  34  is made of high density plastic or similar materials already known to be used in connection with making reciprocating floor conveyors. 
     The dimensions of the gap filler  24  provided in  FIG. 5  are applicable to the embodiments illustrated in  FIGS. 7-19 . Referring now to  FIGS. 11-13 , installation of the gap filler  24  will be described in greater detail. 
     Referring first to  FIG. 11 , the roll-formed steel floor slat  10  is shown according to the configuration it would take following the roll-forming process, which would be known in the art. While the steel thickness might vary, a steel thickness of 3 millimeters may be typical. The steel slat has a top portion  42 , opposite downwardly depending, vertical side portions  44 ,  46 , and inwardly bending lower side portions  48 ,  50 . 
     The inwardly bending lower side portions  48 ,  50  define slants toward the center line of the slat  10 . The opposite edges  49 ,  51  of these side portions are spaced a certain distance apart and create an open width on the bottom of the slat  10 . This width opens into the hollow space created by the slat&#39;s various walls  42 ,  44 ,  46 ,  48 ,  50 , just described. 
     The vertical side portions  44 ,  46  of the steel floor slat  10  define the “gap” between the various steel slats  10  when installed as part of the reciprocating floor conveyor system. As is further described below, the inwardly bending side portions  48 ,  50  provide surfaces for connecting the lower portion  28  of the gap filler  24  to the steel slat  10 . 
     The left-hand side of  FIG. 11  shows the gap filler  24  about to be connected to the slat  10 . The right-hand side of  FIG. 11  shows the gap filler  24  attached to the slat  10 . There, the lower portion  28  of the gap filler  24  is wrapped around the slat&#39;s inwardly bending portion  50 , with the slat&#39;s vertical side portion  46  being captured by the flex in the gap filler  24 , which pinches slat side portion  46  generally at the points indicated by arrows  52 ,  54 , respectively. The gap filler dimensions illustrated in  FIG. 5  are sized to pinch a 3 millimeter steel slat, although these dimensions could be changed for different installation configurations. 
     Continuing with  FIG. 11 , the right-hand side of the Figure shows how the slat/gap filler combination might be provided to an installer prior to installation of the slat/gap filler in a reciprocating floor conveyor system. It should be noted from the Figure that the vertical elevation of the gap filler&#39;s upper portion  26  at the top point (see reference numeral  56 ) is close to the plane of the slat&#39;s load-bearing surface (reference numeral  58 ). There is also a space, indicated generally by arrow  60  in  FIGS. 11 and 12 , that is present between steel slat edge surface  62  and gap filler surface  64 . 
       FIG. 12  illustrates the same gap filler configuration described above, but with the steel slat  10  resting on the bearing  34  and steel subdeck  32 , side-by-side with the same slat/bearing/subdeck combination to the immediate right. This is illustrative of the position of the gap filler  24  during floor slat installation. It should be noted that, at this point, a narrow gap (indicated by arrow  61 ) still exists between the outside surface  63  of the gap filler  24  and the outside surface  65  of the slat&#39;s sidewall  44 . Then, the installer pushes down (see arrow  66  in  FIG. 12 ) on the top  56  of the gap filler  24  to shift (some could call it a type of snap fit) the gap filler to the position shown in  FIG. 13 . There, the vertical elevation of the gap filler&#39;s upper portion  26  at the top point  56  is pushed down below the plane of the slat&#39;s load-bearing surface  58  and shifts slightly laterally to contact the side of the adjacent slat (see reference numeral  67  in  FIG. 13 ), thereby closing the narrow gap  61  described above; the previously described “pinch” between points  52  and  54  on the slat&#39;s side  46  moves down to the approximate location of the bend between the slat&#39;s side  46  and inwardly bending portion  50 ; and gap filler surface  64  rotates and shifts slightly so that surface  64  rests directly against slat surface  62  in lieu of the previously described space  60 . This also creates a new space at the location indicated by arrow  68 . 
     The angle of gap filler surface  64  (which could be called a positioning angle) and other gap filler dimensions are selected so that surface  64  matches the angle of slat edge surface  62  after the shift (caused by the installer pushing the gap filler&#39;s upper portion  26  downwardly). Matching the angles of these surfaces keeps the upper portion  26  of the gap filler sealing the gap properly (between adjacent slats). As indicated above, gap filler specifications are described in detail directly on  FIG. 5 . As indicated in the Figure, the positioning angle on the gap filler  24  illustrated there is 37 degrees on a non-attached gap filler. These dimensions could vary if other variations are made to other components. 
       FIGS. 14 and 15  illustrate the above gap filler installation for the aluminum subdeck configuration ( FIG. 14  is a counterpart of  FIG. 12  while  FIG. 15  is a counterpart of  FIG. 13 ), while  FIGS. 16 and 17  illustrate the same installation but with fixed side slats  70 ,  72  that would be (typically) next to the bottom wall of a trailer, one on each side. The trailer is not illustrated, but a person skilled in the art would recognize that these Figures are representative of a larger number of slats that span the distance, from side-to-side, within the trailer&#39;s walls, which is typical for reciprocating floor slat systems. The number of slats is usually defined by installation application. 
       FIG. 18  illustrates an end cap installation for steel slat  10 . It is well understood how bulk materials exit a reciprocating floor slat conveyor. In the present configuration, an end cap  74  has a portion  76  that is inserted into the end  78  of the slat  10  (there would be no bearing structure at that location). The end cap  74  is held in place by fasteners  80 ,  82 . A series of over-sized openings (indicated generally at  84 ) in the lower portion  28  of the gap filler  24  at this end location enables rivet fasteners  86 ,  88  to secure the gap filler  24  to the slat  10  at the end location only.  FIG. 19  shows the final end cap installation in cross-section. 
     Finally, referring to  FIG. 20 , the single-piece bearing  34  described above is made to snap fit around subdeck lateral edges  90 ,  92 . The bearing  34  can flex at locations  94 ,  96  so that bearing portions  98 ,  100  are captured in place by subdeck lateral edges  90 , 92 . This is the same for the steel subdeck configuration  32  previously described (see  FIGS. 9 and 10 ). The single-piece bearing  34  is otherwise captured within the perimeter or envelope defined by the top and side walls  42 ,  44 ,  46 ,  48 ,  50  of the steel slat  10 . 
     The side-to-side width of the bearing  34  is less than the width between the opposite edges  49 ,  51  of the slat lower side portions  48 ,  50  that were previously described above (see  FIG. 11 , for example). Generally speaking, the side-to-side width of the bearing  34  is the distance between arrows  102  and  104  in  FIG. 20 . The idea is to create a bearing width within the envelope of the hollow slat  10  that is too wide for the bearing to be easily removed through the lower side of the slat. What this means is that the plurality of bearings  34  that will be used for a typical conveyor installation may be inserted end-wise into the hollow slat  10 . In such case, and referring to  FIG. 21 , the combination of slat  10  and bearing  34  may then be installed onto the underlying subdeck structure (whether it be aluminum or steel) at the same time by snap-fitting the bearing onto the subdeck (while it is inside the slat  10 ) and then later securing individual slats  10  to conveyor drive structure (not shown in the drawings). The conveyor drive structure for reciprocating floor slat conveyors is well known in the art. 
     It is to be understood that the design is under development and test and may change as the design is further developed. As an example, while the gap filler seal described above is intended to make steel slats a commercially viable design in the marketplace, it may later prove to work for aluminum slat configurations. For this reason, the foregoing is not intended to limit patent protection. To the extent patent protection is limited, all limits on patent protection are defined by the patent claim or claims that follow.