Patent Publication Number: US-2012031864-A1

Title: Shelf

Description:
TECHNICAL FIELD 
     The present invention relates to shelves and more particularly to shelves formed of mould plastics material. 
     BACKGROUND OF THE INVENTION 
     Typical shelving includes generally upright posts that support one or more generally horizontally oriented shelves. The shelves have sockets that receive the posts so as to be secured thereto. 
     It is not uncommon to form the shelves with a metal frame about which there is moulded a body of plastics material. 
     The abovementioned shelves have the disadvantage that frequently the shelf twists due to stresses within the shelf. Accordingly the shelf is no longer generally planar. 
     OBJECT OF THE INVENTION 
     It is the object of the present invention to overcome or substantially ameliorate the above disadvantage. 
     SUMMARY OF THE INVENTION 
     There is disclosed herein a shelf of generally square or rectangular configuration so as to have four sides and four corners, the shelf including: a pair of elongated frame members, the frame members being generally parallel and transversely spaced, each frame member being located adjacent a respective side of the shelf; 
     an insert at each corner to be engaged by a post that supports the shelf; 
     a body moulded of plastics material with the frame members and inserts embedded in the body; and wherein 
     a space is provided between each insert and adjacent frame member. 
     Preferably, the pair of frame members is a first pair of frame members, and the shelf includes a second pair of elongated frame members, the second frame members being generally parallel and transversely spaced, and generally perpendicular to the first members, with the inserts being spaced from each adjacent frame member, and the second frame member being located adjacent a respective one of the sides. 
     Preferably, the body is injection moulded with each frame member and insert embedded in the body as the body is injection moulded. 
     Preferably, each frame member is metal. 
     Preferably, each insert is metal. 
     Preferably, each insert is of a generally square transverse cross section so as to provide for upwardly extending sides surrounding a hollow to receive an associated post, with said sides converging upwardly. 
     Preferably, each frame member is non planar so as to have longitudinally extending recesses and/or ridges. 
     Preferably, each frame member has smooth external surfaces. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A preferred form of the present invention will now be described by way of example with reference to the accompanying drawings wherein: 
         FIG. 1  is a schematic top plan view of a shelf; 
         FIG. 2  is a schematic sectioned side elevation of the shelf of  FIG. 1 ; 
         FIG. 3  is a schematic end elevation of the shelf of  FIG. 1 ; 
         FIG. 4  is a parts exploded isometric view of portion of the shelf of  FIG. 1  and a post; 
         FIG. 5  is a schematic side elevation of the post and shelf as seen in  FIG. 4 ; 
         FIG. 6  is a schematic top plan view of the shelf and post as seen in  FIG. 5 ; 
         FIG. 7  is a schematic side elevation of the post of  FIGS. 4 and 5 ; 
         FIG. 8  is schematic top plan view of the post of  FIG. 7 ; 
         FIG. 9  is a schematic sectioned side elevation of the post as shown in  FIG. 8  sectioned along the line  9 - 9 ; and 
         FIG. 10  is a schematic end elevation of a frame member employed in the shelf of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In the accompanying drawings there is schematically depicted a shelf  10 . The shelf  10  may be of a square or rectangular configuration so as to have a pair of first sides  11  that are generally parallel and transversely spaced, and a pair of second sides  12  that s are generally parallel and transversely spaced, and generally perpendicular to the sides  11 . The shelf  10  also has four corners  13 . 
     The shelf  10  has a body  14  injection moulded of plastics material. When the body  14  is moulded, the mould includes a frame including a first pair of elongated frame members  15  and a second pair of elongated frame members  16 . The frame members  15  are generally parallel and transversely spaced. The frame members  16  are also generally parallel and transversely spaced but generally perpendicular to the frame members  15 . At each corner there is provided an insert  17 . Each insert  17  provides a socket  18  within which a post  19  is received. Each frame member  15 / 16  is located adjacent a respective side  11 / 12 . 
     Preferably each of the members  15 / 16  and inserts  17  are formed of metal, preferably steel. 
     When moulding the body  14 , the members  15 / 16  and insert  17  are located in the mould. However the members  15 / 16  are positioned so that there is a gap  20  between each member  15 / 16  and its adjacent inserts  17 . The gaps  20  provide for shrinking of the body  14  and movement between the body  14  and the members  15 / 16 . By providing for this relative movement, the shelf  10  is less likely to deform when the body  14  cools. 
     Each socket  18  is of a generally square transverse cross section so as to receive the post  19 . The post  19  includes a post member  21  that has a plurality of spaced recesses  22  that enable the shelf  10  to be located at a desired height. Engaged in each socket  18  is a first post sleeve  23  through which the post member  20  passes, and a securing sleeve  24  that is located between the sleeve  23  and the post member  21 . As best seen in  FIGS. 8 and 9 , each securing sleeve  24  includes projections  25  that engage within a selected group of recesses  22  to secure the shelf  10  at a desired height relative to the post member  21 . As is best seen in  FIG. 9 , the securing sleeve  24  has upwardly converging sides  26 , while each associated sleeve  23  has four sides that taper upwardly so as to engage with the sides  26  so as to wedge the projections  25  in the associated engaged recesses  22 . 
     As best seen in  FIG. 10 , each frame member  15 / 16  is not planar and preferably includes longitudinally extending ridges  27  and longitudinally extending recesses  28 . Each member  15 / 16  has a smooth external surface so as to aid in movement of the body  14  relative to the members  15 / 16  when the body  14  is cooling (shrinking). Preferably, each member  15 / 16  has a thickness of about 2.5 to 3 mm. Such a thickness enables each reinforcing member  15 / 16  to penetrate any plastics material that may cover an end of the members  15 / 16  adjacent the gaps  20 .