Abstract:
A support base is made of metal by die casting for supporting heavy articles above for example ground or floor, and includes a rectangular flat grid plate having four corners from which pillars extend. Intermediate pillars extend from middle positions of long edge faces of the rectangle and a center pillar extends from a center of the rectangle. The rectangular grid plate has opposite end edges on which tenons and mortises are formed respectively and opposite side edges on which tenons and mortises are formed respectively so that a plurality of support bases can be connected together by the tenon-and-mortise coupling between adjacent support bases to expand a covering area of the support bases.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates generally to a support base that has a flat structure having a large surface area for being laid on for example floor to support and isolate an article thereon from humidity of the floor surface or ground, and in particular to such a support base made of metal for supporting heavy articles thereon. 
   2. The Related Art 
   Machinery and/or large quantity of articles are commonly positioned on for example floor or ground and often a support base, such as pallets, timbers, and thick paper boards, is positioned below the machinery or the articles to isolate the articles from contacting contaminants or humidity on the floor or ground. For heavy articles, the support base is often collapsed, and even broken, or ages, for a long term use. This adversely affects safety and security of the articles and those of the surrounding in which the articles are stocked. Further, moving and organizing the conventional support base is very time-consuming and labor-consuming and is often subject to the space limitation of the surrounding where the articles are to be stocked. 
   Thus, it is desired to have a heavy-duty support base that can carry heavy articles for a long time without undesired damage or breaking. 
   SUMMARY OF THE INVENTION 
   Thus, the present invention is aimed to provide a support base that is made of metal castings so as to be of heavy duty for carrying heavy articles without damage or breaking. 
   The present invention also provides a metal support base that allows expansion in longitudinal and lateral directions in an easy and organized manner so as to facilitate laying of a large quantity of support bases to cover an expanded area. 
   To realize the above objectives, in accordance with the present invention, there is provided a support base made of metal by die casting for supporting heavy articles above for example ground or floor, and comprising a rectangular flat grid plate having four corners from which pillar extend. Intermediate pillars extend from middle positions of long edge faces of the rectangle and a center pillar extends from a center of the rectangle. The rectangular grid plate has opposite end edges on which tenons and mortises are formed respectively and opposite side edges on which tenons and mortises are formed respectively so that a plurality of support bases can be connected together by the tenon-and-mortise coupling between adjacent support bases to expand a covering area of the support bases. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will be apparent to those skilled in the art by reading the following description of a preferred embodiment thereof, with reference to the attached drawings, in which: 
       FIG. 1  is a perspective view showing a support base constructed in accordance with the present invention; 
       FIG. 1A  is an enlarged view of a circled portion of  FIG. 1 ; 
       FIG. 2  is also a perspective view of the support base of the present invention taken from a bottom side; 
       FIG. 3  is a perspective view showing a process of connecting two support bases of the present invention in an end by end manner; 
       FIG. 3A  is an enlarged view of a circled portion of  FIG. 3 ; 
       FIG. 4  is a perspective view showing two support bases of the present invention are connected together in the end by end manner; 
       FIG. 5  is perspective view showing two support bases of the present invention are connected together in a side by side manner; and 
       FIG. 6  is a perspective view showing four support bases of the present invention connected together. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   With reference to the drawings and in particular to  FIGS. 1 ,  1 A, and  2 , a support base constructed in accordance with the present invention, generally designated with reference numeral  1 , is made of a rigid and strong material by known means, such as die castings of metal. The support base  1  has a flat body  11  in the form of a rectangular grid plate comprising a plurality of longitudinally extending ribs and laterally extending ribs intersecting each other and defining hollow cells  12 . Thus, the body  11  has two opposite end edges that extend in the lateral directions and are spaced from each other in the longitudinal direction and two opposite side edges that extend in the longitudinal direction and are spaced from each other in the lateral direction whereby the end edges and the side edges intersect each other at four corners, which are right-angled in the embodiment illustrated, but do not need to be so. 
   Pillars  13 ,  14 ,  15 ,  16  extend downward from the four corners respectively to define a height and are positionable on a fixture surface, such as a floor or ground. An intermediate pillar  17 ,  18  is formed at a middle position along each side edge so that the intermediate pillar  17 ,  18  is substantially midway between two opposite pillars  13 ,  15  (or  14 ,  16 ). A further center pillar  19  is formed at a center of the rectangular plate of the body  11 . The intermediate pillars  17 ,  18  and the center pillar  19  extend downward from the flat plate to be positioned on for example the ground. 
   On the face of one of the end edges, a plurality of recesses or mortise slots are defined, and on the face of the other one of the end edges, corresponding projections or tenons are formed, whereby when two support bases  1  of the present invention are positioned next to each other in an end-by-end manner, the projections or tenons of a first one of the two support base  1  are fit into and engageable with the recesses or the mortise slots defined in a second one of the two support bases  1  so that the two support bases  1  are connected together to expand to a larger coverage area in the longitudinal direction. 
   In the embodiment illustrated, a mortise slot  13   b,    14   b  is defined in a first end face of the rectangular grid plate  11  at a location corresponding to each pillar  13 ,  13  of that first end edge, and a tenon projection  15   a,    16   a  is formed in a second end face of the rectangular grid plate  11  at a location corresponding to each pillar  15 ,  16  of that second end edge. The mortise slots  13   b,    14   b  extend in a direction substantially parallel to the height of the pillars  13 ,  14 ,  15 ,  16 . The length of the mortise slots  13   b,    14   b  measured along the height direction is substantially the same as the length of the tenon projections  15   a,    16   a  measured in the height direction, or the length of the mortise slots  13   b,    14   b  is longer than that of the tenon projections  15   a,    16   a  to ensure proper receipt of the projections  15   a,    16   a  in the mortise slots  13   b,    14   b  when two support bases  1  are connected end by end. 
   Similarly, on the face of one of the side edges, a plurality of recesses or mortise slots are defined, and on the face of the other one of the side edges, corresponding projections or tenons are formed, whereby when two support bases  1  of the present invention are positioned next to each other in an side-by-side manner, the projections or tenons of a first one of the two support base  1  are fit into and engageable with the recesses or the mortise slots defined in a second one of the two support bases  1  so that the two support bases  1  are connected together to expand to a larger coverage area in the lateral direction. 
   In the embodiment illustrated, a mortise slot  13   a,    15   b,    17   b  is defined in a first side face of the rectangular grid plate  11  at a location corresponding to each pillar  13 ,  15  of that first side edge and the intermediate pillar  17 , and a tenon projection  14   a,    16   b,    18   a  is formed in a second side face of the rectangular grid plate  11  at a location corresponding to each pillar  15 ,  16  of that second side edge, and the intermediate pillar  18 . The mortise slots  13   a,    15   b,    17   b  extend in a direction substantially parallel to the height of the pillars  13 ,  14 ,  15 ,  16 . The length of the mortise slots  13   a,    15   b,    17   b  measured along the height direction is substantially the same as the length of the tenon projections  14   a,    16   b,    18   a  measured in the height direction, or the length of the mortise slots  13   a,    15   b,    17   b  is longer than that of the tenon projections  14   a,    16   b,    18   b  to ensure proper receipt of the projections  14   a,    16   b,    18   b  in the mortise slots  13   a,    15   b,    17   b  when two support bases  1  are connected side by side. 
   In the embodiment illustrated, and as best seen in  FIG. 1A , the mortise slots and the tenon projections are dovetail-shaped. However, it is apparent that other shapes of the mortise and tenon can be used, provided they can ensure inter-engagement with each other to connect two support bases  1  together. Also, as shown in the drawings, the length of the mortise slots is substantially shorter than the height of the pillars so that engagement between two support bases  1  can be done efficiently and easily In other words, the mortise slots and the tenon projections do not extend along the full height of the pillars. 
   Also referring to  FIGS. 3 and 3A , to connect two support bases  1  in an end-by-end manner, the tenon projections  15   a,    16   a  of a first support base  1  are simultaneously fit into the mortise slots  13   b,    14   b  of a second support base  1  to have the tenon projections  15   a,    16   a  and the mortise slots  13   b,    14   b  engaging each other and thus connecting the two support bases  1  together in an end-by-end manner. Once the tenon projections  15   a,    16   a  are completely received in the mortise slots  13   b,    14   b,  the grid plates  11  of the two support bases  1  align with each other and top surfaces of the grid plates  11  flush with each other, as shown in  FIG. 4 . Thus, the support bases  1  are expanded in the longitudinal direction. 
   Referring to  FIG. 5 , similarly, to expand the support bases  1  in the lateral direction, the tenon projections  14   a,    16   b,    18   a  of the first side face of a first support base  1  are simultaneously fit into the mortise slots  13   a,    15   b,    17   b  of the second side face of a second support base  1  to connect two support bases  1  together. In this way, the two support bases  1  are connected together side by side and the support bases  1  can expand in the lateral direction. 
   Apparently, the support base  1  can expand in both the longitudinal direction and the lateral direction by connecting four support bases  1  together as shown in  FIG. 6 . The connection between adjacent support bases  1  in either the longitudinal direction or the lateral direction is the same as those described with reference to  FIGS. 3 and 4 . Thus, detailed description is no longer needed for the expansion of the support base  1  shown in  FIG. 6 . 
   It is apparent from the above description that the mortise-and-tenon connection between adjacent ones of the support base  1  of the present invention allows the support bases  1  to be securely and firmly connected in an efficient and effective manner. 
   Further, the support base of the present invention is made of a rigid material, such as metal, so that the support base is of a heavy-duty structure that supports heavy articles thereon and isolates the articles from contact with contaminant or humidity on the floor or ground by the downward-extending pillars. 
   Further, the support base can easily expand by connecting a plurality of the support bases in both the longitudinal and lateral directions without requiring any special tools so that the expansion of the support base can be made easily in any limited space and at any locations. 
   Although the present invention has been described with reference to the preferred embodiment with reference to the drawings thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims.