Patent Publication Number: US-6981454-B2

Title: Center post and system for a rack

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The field of this invention lies within the art of racks and shelving. More particularly, it lies within the art of supporting a rack and shelving with a number of posts, shelves, and cross members. The posts, shelves, and cross members can be formed of metal having a substantial plastic coating therearound to reduce rust and deterioration while at the same time having improved strength based upon an inner metal core. 
   2. The Prior Art 
   The prior art relates to shelving, particularly for usage with regard to food products in the institutional, industrial, and general restaurant food service art. 
   It has been found in the past that such shelving made of aluminum, steel, plastic, and other materials have substantial limitations. These limitations can be in the form of rust when it comes to steel, even though the steel has been painted. With respect to aluminum, the strength of the shelving is oftentimes compromised. As to the use of plastic for shelving without any strengthening, it has been found that such plastic can be formed and not be sufficiently strong to support such shelving. 
   Also, it has been well known in the food service area, particularly with regard to institutional, industrial, and restaurant food service activity, that substantial quantities of food must be stored on racks. The food must be readily accessible and at the same time visible to maintain proper inventories and availability. 
   The shelving, posts, and cross members of the invention hereof provide for excellent storage with respect to refrigerators and freezers based upon the ability to withstand varying temperatures. 
   The invention hereof overcomes the drawbacks of prior art shelving by being molded without welds and substantially avoids rust. To this extent, the combination with the plastic and steel core help to support the shelving hereof in a most desirable manner. 
   The weight bearing components are made of a steel core with a polypropylene or other suitable plastic exterior, thus making the shelving strong and easy to clean. 
   The prior art shelving when made of various metals as previously set forth does not enhance the weight bearing characteristics combined with low oxidation. 
   The shelving of this invention is based upon easy to use assembled components that provide for posts and cross members from which shelving can be suspended. The shelving is smooth with a polypropylene surface which is easy to clean and wipe. Liquid and dirt do not affect the overall characteristics of the shelving. 
   Regardless of the foregoing, it has been found that even with respect to the high strength steel that is used as the core as to the cross members, that sometimes the cross members will sag under significant load. To this extent, this invention overcomes the deficiencies of the prior art by providing a center post which enhances the overall support of members that are used for cross members in supporting the bending moment of the cross members of the shelving. As will be seen hereinafter, this invention substantially avoids cross member sag while at the same time maintaining the enhanced characteristics of the invention over the prior art as to metal and other types of shelving. 
   SUMMARY OF THE INVENTION 
   In summation, this invention provides for a shelving system having reinforced steel posts and cross members formed with a steel core to provide strength and durability with a plastic molded exterior surface to reduce rust and other deterioration while at the same time creating a system with a center post support for cross members to avoid sag and bowing of such cross members. 
   More specifically, the invention incorporates the aspects of posts, cross members, and various linkages with shelving. The posts and cross members can be formed with a steel core. The steel core provides strength and durability. At the same time, the steel core is formed with a molded surface therearound which can be a polypropylene or other type of suitable plastic. 
   The posts and cross members can be easily joined together by means of dovetails molded on the posts that mate with the cross members having molded dovetail receipt openings. Further to this extent, the cross members can be incorporated with the posts to form support in various directions as will be set forth hereinafter. 
   In order to enhance the support of the cross members, an adjustable mid support for the cross members is utilized which can be snapped into place and easily adjusted for various loads on the shelving supported by the cross members and the posts. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows a front elevation view of the shelving of this invention with a significant load thereon being supported in part by a center post. 
       FIG. 2  shows a detailed fragmented portion that has been encircled by circle  2  of  FIG. 1 . 
       FIG. 3  shows a sectional view of the center post in the direction of lines  3 — 3  of  FIG. 2 . 
       FIG. 4  shows a fragmented perspective view of the center post and cross members. 
       FIG. 5  shows a fragmented perspective view looking upwardly at the center post and cross members. 
       FIG. 6  is a perspective view of the disengaged connection between an upright tube and a spar in a rack according to the invention; 
       FIG. 6A  shows a modification of the connection according to  FIG. 1 ; 
       FIG. 7  shows the upper end part of an upright tube, partly in section; 
       FIG. 8  is a side view of the lower end part of an upright tube; 
       FIG. 9  shows an end section of a transverse connecting member between two upright tubes, in a vertical section; 
       FIG. 10  is a side view of part of an upright tube with a pair of coupling lugs; 
       FIG. 11  is a cross-section on line VI—VI of  FIG. 5 ; 
       FIG. 12  is a side view of an end section of a spar, partly in longitudinal section; 
       FIG. 13  is a cross-section through a spar with a corner-connecting clip hooking laterally around the latter; 
       FIG. 14  is a horizontal section through the connection between an upright tube and two spars lying at right angles to each other, and; 
       FIG. 15  is an end view, to a reduced scale, of the spar, with the coupling part removed, in the embodiment according to  FIG. 6A . 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Looking specifically at  FIG. 1 , it can be seen that the rack or shelving of this invention is shown generally as shelving  10 . The rack or shelving  10  is supporting a plurality of sacks or bags  12  thereon. The plurality of sacks  12  are on an upper shelf  14  and a lower shelf  16 . The shelving  14  and  16  is shown with a number of cross member supports that shall be referred to hereinafter as traverses  18  and  20 . 
   The traverses  18  and  20  generally support the shelving between four posts  22  and  24 . The posts  22  and  24  have a series of dovetailed receipt areas therein in order to receive dovetails of the traverses  18  and  20 . Each respective dovetail on the posts  22  and  24  provides for an adjustment as to height and spacing of the traverses  18  and  20  that support the shelving. The dovetails can be interchanged as to receipt portions as projecting dovetails on either posts  22  and  24  or the traverses  18  and  20 . 
   In order to connect the posts  22  and  24  a pair of upper post connectors  30  and  32  are utilized. These upper post connectors  30  and  32  have caps that slide over and are secured to the tops of the posts  22  and  24 . 
   To provide for stability and support on the lower portion of the posts  22  and  24 , post connectors  34  and  36  are utilized. These post connectors  34  and  36  slide upwardly onto the posts  22  and  24  so that cross stability is realized in both directions by the respective traverses and post connectors. 
   A number of various types of shelving can be extended or span between the traverses  18  and  20  so as to allow for the support and access of such items as bags  12  being accessed or any other types of items. 
   The foregoing configuration as to the dovetails and the posts  22  and  24  as well as the relationship of the traverses  18  and  20  and the post connectors  30 ,  32 ,  34 , and  36  can be seen in European Patent 0686817A2 based on European Application 95201281.3 naming Hense, et al as inventors. The features of the foregoing patent assigned to the Assignee of the Applicant herein are incorporated herein by reference as to the dovetailed showings between the traverses  18  and  20  and the posts  22  and  24  as well as the respective post connectors. Also, the nature of the metal structure and core of that patent are included herein by reference as part of the supporting specification. 
   The rack according to the invention and the European Application: 95201281.3, now European Patent 0686817A2 is normally composed of at least two uprights and supports extending therebetween at different heights. 
   Each upright (i.e., posts  22  and  24 ) is composed of two upright tubes  201 , which are connected to each other in the vicinity of the upper and lower ends by transverse connecting members, as will be described in detail hereafter. Each support (i.e., traverses  18  and  20 ) comprises two spars  202 , on which plates preferably formed from synthetic material are laid. These plates do not form any part of the invention and are therefore only mentioned and illustrated incidentally in the description of the corner-connecting clip according to  FIG. 1 . 
   The upright tubes  201  consist of a metal core tube  3  preferably consisting of steel, preferably with a rectangular cross-sectional shape. 
   The metal core tube  203  extends over the entire (standard) length (for example 1.8 m) of the upright tube and is provided at its upper end (see  FIG. 7 ) and at its lower end (see  FIG. 8 ) with an insert  204  or  205  closing off the respective end. In this case, the upper insert  204  is formed by a closure cap, whereas the lower insert  205  consists of an insert bush with a flange  206  resting on the front edge of the core tube  203  and with an internal thread for receiving an adjusting foot  207 . The core tube  203  is provided over the entire length with a synthetic material covering (for example of polypropylene), which can be applied by known spraying methods and which likewise extends around the closed ends of the core tube. 
   Close to the upper and lower ends of the upright tube  201 , the covering  208  has a wall thickness which over a certain height h 1  ( FIG. 7 ) or h 2  ( FIG. 8 ) is reduced in comparison with the remaining covering and decreases towards the respective front ends. 
   In the vicinity of the two ends, the upright tube thus has a section  201   a  or  201   b , whereof the outer surface is slightly conical (for example with a concinnity of 2°). 
   These slightly conical end sections  201   a  or  201   b  form the engagement points for the bush-shaped ends  10  of a transverse connecting member  203 , which is shown in  FIG. 9  and whereof the cavity  210  has a shape and concinnity corresponding to those of the above-mentioned end sections  201   a  or  201   b.  The bush-shaped end sections of the transverse connecting members, which connect the upper ends of two upright tubes, may in this case, be closed at their tapered ends by a thin end wall  211 . For connecting the lower ends of two upright tubes, an end wall of this type is omitted or removed. 
   It will become clear that two upright tubes  201  and the two transverse connecting members  209  can be assembled with a wedge action between the inter-engaging parts  201   a,    210  or  201   b,    210  of the upright tubes  201  and the transverse members  209  to form an upright which is resistant to bending and inherently stable. 
   The tubes  201  of each upright are provided with laterally projecting coupling parts  213 . These coupling parts are in the form of elongated lugs extending in the longitudinal direction of the upright tube  201 , whereof the longitudinal side  213 , a remote from the upright tube, extends parallel to the axis of the upright tube and the two adjoining longitudinal sides  213   b  and  213   c,  lying opposite one another, diverge in the direction of the lower end of the respective upright tube. 
   The wedge-shaped lugs  213  obtained in this way are arranged in pairs, which are distributed uniformly over the length of the upright section. In this case, the distances between successive pairs of lugs correspond to the desired mutual spacing between the supports in the rack to be formed. 
   The lugs  213  all project from one longitudinal side of the upright section, in which case the longitudinal sides  213  remote from each other of the lugs  213  belonging to the same pair, lie in one plane with the adjoining longitudinal sides of the upright tube. 
   Furthermore, the longitudinal sides  213   c  of the lugs  213  form an angle less than 90° with the adjoining longitudinal side of the upright tube, due to which the lugs  213  have a cross-section whereof the profile towards the upright tube is undercut. As can be seen from the drawing, the lugs are rounded on the upper and lower ends. The lugs  213  are formed in one piece with the covering  8  supported by the core tube  203 . 
   Reference is now made to  FIG. 12 , in which the spar  202  belonging to a support is shown in longitudinal section. In the same way as the above-described upright tube, the spar  202  also has a metal (preferably consisting of steel) tube core  215  with a preferably rectangular cross-sectional shape. 
   The metal core tube  215  closed at the ends with caps  216  is covered over its entire length, all around and around the ends with a synthetic material covering  217  of, for example, polypropylene. Coupling parts  218  formed in one piece with the covering  217  are provided at the ends of the spar  202 . These coupling parts  218  are approximately in the shape of a 202 angle section, whereof the upper end lies in one plane with the upper wall of the spar and which projects on the under side to a certain extent below the spar. In this case, one flange  218   a  of the angle profile is displaced laterally to some extent with respect to the vertical central longitudinal surface of the spar  202 , whereas the second flange  218   b  lies in one plane with the respective front end of the spar. 
   Provided in the flange  218   a  is a housing  219 , whereof the side walls  219   a  and  219   b  have a mutual shape which corresponds to that of the opposite longitudinal sides  213   b  and  213   c  of the above-described coupling lug  213 . In this case, the side wall  219   b  lies in one plane with the end face of the flange  218   b,  whereas the side wall  219   b  diverges downwards with respect to the side wall  219   a  and on the other side lies somewhat obliquely with respect to the bottom surface of the housing  219 . 
   The length  212  of the housing  219  is at least so much greater than the length  211  of the lug  213 , that the coupling part  218  with its housing  219  can be fitted from the side (see direction of arrow A in  FIG. 6 ) on a coupling lug  213  projecting from an upright tube  201 . If the coupling part  218  is moved downwards with respect to the upright tube  201  (see arrow B in  FIG. 6 ), the lug  213  is clamped in the housing  219  under the wedge effect. This wedge effect accompanies the clamping of the spar  202  with respect to the respective upright tube in two mutually perpendicular directions, and indeed on the one hand in the direction of arrow A and on the other hand in the direction of arrow C ( FIG. 6 ). 
   The final coupling between the upright tube  201  and (i.e., posts  22  and  24 ) spar  202  (i.e., traverse  18  and  20 ) is illustrated in  FIG. 14 , in which it is furthermore shown how a second spar  202  lying at right angles to the spar  202  can be located by means of a corner-connecting clip  225 . 
   In order that a rack formed by a first upright and an upright with supports located therebetween, can be enlarged by one section, which is at right angles to the first said rack and contains supports, which lie in one plane with those of the aforementioned rack, corner-connecting clips are used. 
   On that side of the rack, where the extension section is to be connected, two corner-connecting clips are placed around the spars of the supports, and indeed one close to one upright tube and a second at a point removed from the latter by the width of the support. 
     FIG. 14  shows the corner-connecting clip  225  to be located in the vicinity of the upright tube and preferably consisting of the same synthetic material as that of the covering of the upright tubes and spars. For locating the corner-connecting clips, on their outer longitudinal sides the spars are provided with an upper edge part  221  bent vertically downwards and a lower edge part  222 , which edge parts together form a housing for the upright leg  223  of an angle clip  225   a,  whereof the horizontal leg  224  may engage resiliently around the lower side of the spar  202  (see  FIG. 13 ). The angle clip  225   a  supports a web  226  projecting vertically, with a coupling lug  227  provided thereon, which corresponds to the coupling lug  213  seated on the upright tubes. 
   In this way, two coupling lugs are formed at two points on the side edge of each support of the rack to be extended at right angles, on which coupling lugs just as many spars can engage, which spars are connected by their other ends to the coupling lugs on the upright tubes of a third upright. 
   Provided on the side of the web  226  remote from the lug  227  is a projection  228  (see  FIG. 14 ), which fills the space between the front end of the spar  202  and the opposite wall of the upright  201 . A similar projection can be used in the corner-connecting clip, which is to be hooked around the spar  202  at an intermediate point. 
   Finally,  FIG. 13  shows part of the synthetic material plates  229 , which are laid overlapping the spars  202  or  202 . 
   In the embodiment according to  FIG. 6A , the upright  300  is provided on one side  300   a  with longitudinal ribs  301  of invariable cross-section and with coupling lugs  313  on the opposite side  300   b.  These coupling lugs  313  consequently differ from the lugs  213  in the embodiment according to  FIG. 6  in that they diverge downwards solely in one direction, and indeed in the plane of the adjoining side  300   c  or  300   d  of the upright. 
   In the embodiment according to  FIG. 6A , the spar  302  is provided with a coupling part  318 , which differs from the coupling part  218  in the embodiment according to  FIG. 6  due to the fact that it is set up for cooperation with both a longitudinal rib  301  as well as an opposing lug  313  of the upright  300 . For this purpose, the coupling part is bent over twice at right angles on one vertical longitudinal edge at  320 , in order that it can engage around a rib  301 , whereas the opposite longitudinal edge  319  is likewise bent twice at right angles. However, in this case, the surface  319   a  has a downwardly diverging shape corresponding to the wedge shape of the lug  313  of the upright  300  to be surrounded. 
   Furthermore, the coupling part  318  is constructed as a separate synthetic material part and on the rear side is provided with an integrally formed projection  321  with a cross-section in the shape of a dovetail and widening out downwards in the shape of a wedge, which fits in a correspondingly shaped recess  322  in the front end of the spar  302  (see  FIG. 15 ). Moreover, the upright  300  and the spar may be constructed in the same manner as was described above in connection with the embodiment according to  FIG. 6 . 
   Looking more specifically at  FIGS. 2 and 3  which have been encircled from circle  2  of  FIG. 1  it can be seen that a center post is shown with a portion of a traverse. In particular, the lower traverse  20  is shown connected to a center post  42 . The center post  42  is comprised of an outer molded column section  44  having an interior steel tubular reinforcement  46 . The interior steel reinforcement  46  is of a columnar nature and terminates at an abutment end  48  co-terminus with the end of the outer plastic portion  44  and a co-terminal point  50 . 
   In order to maintain the rigidity of the center post  42  underneath the traverse  20 , a cross member that can be in the form of a post connector  34   a  has been shown. The cross member  34   a  has the interior portion thereof at the end formed as an opening  52  in a collar  51  which can circumscribe the outer plastic portion  44 . The collar portion  51  with the space  52  terminates against a ledge or small dimension portion  56  of the outside plastic portion  44  of the post  42 . 
   In order to seat the traverse  20  on the center post  42 , an end cap  66  is shown. The end cap  66  has an insert  68  that inserts into the metal portion  46  of the center column. The end cap  66  with its insert  68  terminates with an upper flattened portion on the interior forming a channel or receipt  70  into which the portions  44  and  46  of the center post  42  can be inserted. In order to secure them, an exterior flange  74  and  76  is shown. 
   The end cap  66  extends upwardly to provide an elongated channel  78  that extends along its length which is spilled over in the form of longitudinal flanges  84  and  86 . These longitudinal flanges  84  and  86  receive the traverse  20  therein based upon lower flanges  90  and  92  on either side of the traverse. 
   In this manner, the traverse  20  with its interior steel portion  21  can be well supported on the center post  42  with the corresponding post connector  34  stabilizing it. 
   In order to adjustably seat the center or support post  42  on a surface to support the traverse  20 , an adjustable end or base foot  100  is seated therein. The adjustable end foot  100  has a metal extension or column  102  which can be in the form of any suitable material terminating in threads  104 . The threads  104  are seated within a metal or plastic sleeve  106  having matching threads. The sleeve  106  with its matching threads  108  allows for adjustment upwardly or downwardly of the foot  100  on its column  102 . Thus, after the sleeve is inserted and formed in any suitable manner to be retained within the metal portion of the column  46 , it can be adjusted as to the foot  100  upwardly and downwardly for centering and balancing the shelving  10 . 
   Various alternatives can be utilized with the invention hereof such as the substitution of steel with hard durable plastic as well as the utilization of steel for instance in the post connectors in the analogous manner to which the tubular steel support  21  has been emplaced within the traverse  20 . Also, various types of plastic can be utilized for molding around the steel core as set forth hereinafter. 
   Inasmuch as the plastic coating or molded covering should be food compatible and meet with FDA food-contact regulations, polycarbonate is deemed desirable and is well received. Polycarbonate is further desirable because of its clarity. 
   Other preferred plastics include among others polyethylenes, polypropylenes, and styrenic resins, in particular, styrene-acrylonitrile (SAN) and acrylonitrile-butadiene-styrene (ABS). 
   The invention can be made from many other plastic materials besides those preferred plastic materials mentioned above. When intended for food use, any of the resins and polymers approved for food use by the Food and Drug Administration can be used keeping in mind that chemically compatible material provides a better bond. Examples of such plastic materials can include among others the homopolymers, copolymers, polymers and mixtures thereof containing:
     Acrylic and modified acrylic plastics;   Acrylonitrile/butadiene/styrene copolymers;   Acrylonitrile/butadiene/styrene/methyl methacrylate copolymers;   Acrylonitrile/styrene copolymers;   Acrylonitrile/styrene copolymer modified with butadiene/styrene elastomers;   n-Alkylglutarimide/acrylic copolymers;   Cellophanes;   Cross-linked polyacrylate copolymers;   1,4-Cyclohexylene dimethylene terephthalate and 1,4-Cyclohexylene dimethylene isophthalate copolymers;   Ethylene-acrylic acid copolymers;   Ethylene-carbon monoxide copolymers.   Ethylene-1,4-cyclohexylene dimethylene terephthalate copolymers;   Ethylene-ethyl acrylate copolymers.   Ionomeric resins;   Ethylene-methyl acrylate copolymer resins;   Ethylene/1,3-phenylene oxyethylene isophthalate/terephthalate copolymers;   Ethylene-vinyl acetate copolymers;   Ethylene-vinyl acetate-vinyl alcohol copolymers;   Fluorocarbon resins;   Isobutylene polymers;   Isobutylene-butene copolymers;   Melamine-formaldehyde resins;   Nitrile rubber modified acrylonitrile-methyl acrylate copolymers;   Nylon resins;   Olefin polymers;   Perfluorocarbon resins;   Polyarylate resins;   Polyaryletherketone resins;   Polyarylsulfone resins;   Poly-1-butene resins and butene/ethylene copolymers;   Polycarbonate resins;   Polyestercarbonate resins;   Polyester elastomers;   Polyetherimide resins;   Polyethylene resins, carboxyl modified;   Polyethylenes, chlorinated;   Polyethylenes, fluorinated;   Polyethylenes, oxidized;   Polyethylene phthalate polymers;   Poly(phenyleneterephthalamide)resins;   Poly(p-methylstyrenes) and rubber-modified poly(p-methylstyrenes);   Poly(oxy-1,2-ethanediyloxycarbonyl-2,6-naphthalenediylcarbonyl)resins;   Polystyrenes and rubber-modified polystyrenes;   Polysulfide polymer-polyepoxy resins;   Polysulfone resins;   Poly(tetramethylene terephthalates);   Polyurethane resins;   Styrene block polymers;   Styrene-maleic anhydride copolymers;   Styrene-methyl methacrylate copolymers;   Textryls;   Urea-formaldehyde resins;   Vinyl chloride-ethylene copolymers;   Vinyl chloride-hexene-1 copolymers;   Vinyl chloride-lauryl vinyl ether copolymers;   Vinyl chloride-propylene copolymers;   Vinylidene chloride/methyl acrylate copolymers; and,   Vinylidene chloride/methyl acrylate/methyl methacrylate polymers.   

   The above list is only intended to be illustrative of the plastics which can be used and is not intended to constitute a limitation to the structure of this invention. Other plastic materials and mixtures thereof will be apparent to one skilled in the art and can be used without departing from the spirit and scope of the invention.