Patent Publication Number: US-6336743-B1

Title: Slide rails of drop-leaf table

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to a drop-leaf table, and more particularly to slide rails of the drop-leaf table. 
     BACKGROUND OF THE INVENTION 
     As shown in FIG. 1, this inventor of the present invention discloses in the U.S. patent Ser. No. 09/280,897 two slide rails  6  for use in a drop-leaf table. The slide rails  6  are made of steel plates by rolling and are provided with a fitting slot  61  having a relatively wide mouth, and a fitting protrusion  62  having a relatively smaller mouth. Another slide rail  7  is provided with a fitting slot  71  which is fitted over the fitting protrusion  62 . The slide rails  6  and  7  are fastened with the table leaves  68  and  78  by the connection pieces  66  and  76 . When the table leaf  68  is pulled, the slide rail  6  is moved along. Now referring to FIG. 2, after the slide rail  6  is pulled out, it is necessary to pull another slide rail  7  out, thereby resulting in inconvenience in using the drop-leaf table. 
     As shown in FIG. 3, the slide rail  6  is provided at one end thereof with an arresting edge  64 . In assembling the table, another end of the slide rail  6  is fitted with the slide rail  7 . The slide rail  6  must be pulled out in the same direction so as to prevent being obstructed by the arresting edge  75 . If the slide rail  6  is damaged, the table leaf  78  can not be removed because it is obstructed by the table leaf  68  which is located over the slide rail  6 . 
     SUMMARY OF THE INVENTION 
     The primary objective of the present invention is to provide a drop-leaf table with slide rails enabling the table leaves to be moved simultaneously in opposite directions. 
     The slide rails of the present invention are made of the steel plates by rolling. The primary rail is provided with a fitting slot having a greater mouth and a fitting protrusion having a smaller mouth. Located between them is a connection plate which is provided in the middle thereof with a support seat provided with a rotary gear. The connection plate is provided in the inside of one end thereof and in the outer side of other end thereof with a connection piece riveted therewith for fastening the table leg. An inner rail and an outer rail are provided with a fitting slot and a fitting protrusion. The connection plates of the inner rail and the outer rail are provided with the toothed holes for receiving the toothed portion of the gear. The outer or inner side of another side is provided with a connection piece riveted therewith for fastening two table legs. When one table leaf is pulled, the outer rail is pulled out along the primary rail such that the gear is actuated by the toothed holes to turn. The inner rail is then actuated by the gear in motion to slide in opposite direction. As a result, two table leaves are in motion at the same time. 
     The connection plate of the primary rail is provided with a through hole opposite to the holes of the two connection pieces for locating two locating members. The toothed holes of the connection plates of the inner rail and the outer rail are provided in one side thereof with an arresting edge extending inward or outward by punching and pressing. When the inner rail and the outer rail are pulled out on the primary rail, they are prevented from sliding out of the primary rail by the arresting edges and the locating members. If the inner rail or the outer rail is damaged, the locating members can be taken out so as to enable the damaged rail to be pulled out for replacement. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows an exploded view of the structure disclosed in the U.S. patent Ser. No. 09/280,897. 
     FIG. 2 shows a schematic view of the slide rails of the U.S. patent Ser. No. 09/280,897. 
     FIG. 3 shows a schematic plan view of the structure in combination of the U.S. patent Ser. No. 09/280,897. 
     FIG. 4 shows an exploded view of the present invention. 
     FIG. 5-1 shows a side view of the present invention in combination. 
     FIG. 5-2 shows a partial sectional view of FIG. 5-1 
     FIG. 6 shows an exploded view of the present invention and the table body. 
     FIG. 7 shows a schematic view of the present invention at work. 
     FIG. 8 shows another schematic view of the present invention at work. 
     FIG. 9 shows still another schematic view of the present invention at work. 
     FIG. 10 shows a schematic view of the slide rails of the present invention in action. 
     FIG. 11 shows a schematic view of another preferred embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As shown in FIGS. 1-5, and FIGS. 5-1 and  5 - 2 , the present invention comprises the component parts, which are described hereinafter. 
     A primary rail  10  is made of a steel material by rolling and is provided with two fitting slots  11  having a greater mouth, and two fitting protrusions  12  having a smaller mouth. A connection plate  13  is located between the fitting slot  11  and the fitting protrusion  12  and is provided in an appropriate position thereof with a rotary gear  15  mounted on a support seat  14 . The connection plate  13  is provided at both ends thereof with a through hole  131 , in the inner side of one end thereof with a connection piece  16  riveted thereto, and in the outer side of other end thereof with a connection piece  16  riveted thereto. The connection pieces  16  are provided with a hole in communication with the through hole  131  for locating two locating members  17  and  18  in different directions. The connection pieces  16  are fastened with legs  19 . 
     An inner rail  20  is made of a steel material by rolling and is provided with two fitting slots  21  having a greater mouth, and two opposite fitting protrusions  22  having a smaller mouth, and a connection plate  23  located between the fitting slots and the fitting protrusions and provided with a row of toothed holes  24  contiguous to one side of the gear  15  of the primary rail  10 . The fitting protrusions  22  are fitted with the fitting slots  11  of the primary rail  10  for slidably receiving the toothed portion of the gear  15  in the toothed hole  24 . The toothed hole  24  of the connection plate  23  is provided with an arresting edge  25  formed outwardly by punching and pressing. The inside of the toothed hole is provided with a connection piece  26  riveted thereto. 
     As outer rail  30  is made of a steel material by rolling and provided with two opposite fitting slots  31  having a greater mouth, and two fitting protrusions  32  having a smaller mouth, and a connection plate  33  provided with a row of toothed holes  34 . The fitting slots  31  are fitted with the fitting protrusions  12  of the primary rail  10  such that the toothed portion of the gear  15  is inserted into the toothed holes  34 . Located in the inner side of the toothed holes  34  of the connection plate  33  is an arresting edge  35  which is formed by punching and pressing. 
     As shown in FIG. 6, two table leaves  27  and  37  form a table body such that the two table leaves and one leg are assembled in conjunction with two sets of slide rails, with each having the primary rail, the inner rail, and the outer rail. The connection piece  16  of the primary rail  10  is fastened with the leg  19 . The table leaf  37  is fastened with the connection piece  36  of the outer rail  30 . The table leaf  27  is fastened with the connection piece  26  of the inner rail  20  such that the rails are actuated by the primary rail to move outward simultaneously. However, the leg and the primary rail do not move to facilitate the displacement of the table leaves  27  and  37 . The lower rail may take advantage of the primary rail to actuate another rail and another table leaf to move outwards. In the meantime, both the leg and the primary rail do not move to facilitate the pulling of two table leaves to result in an expansion of the area of the table top. At this time, the table leaves  27  and  37  are joined together by means of a cover plate  40 . The table top is thus expanded. As shown in FIG. 4, FIG. 5-2, and FIG. 7, in order to reduce the area of the table top, the table leaf  37  is pushed to cause the outer rail  30  to make use of the inner displacement of the toothed holes  34  to actuate another toothed hole  24  of the inner rail  20  to move inward simultaneously. The inner rail  20  of the table leaf  27  also displaces simultaneously. The inner rail  20  and the outer rail  30  of the primary rail  10  are stacked to draw the table leaves  27  and  37  together. On the other hand, as shown in FIG. 5-2, FIGS. 8 and 9, only the table leaf  37  is pulled out, thereby resulting the outer rail  30  to make use of the toothed holes  34  to slide outward. As a result, the gear  15  of the primary rail  10  is actuated to turn such that the gear  15  actuates the toothed holes  24  of the inner rail  20  to move outward at the same time. When the outer rail  30  slides outward, the arresting edge  35  is stopped by the locating member  17  of the primary rail  10 . The arresting edge  25  of the inner rail  20  is stopped by the locating member  18  of the primary rail  10 . As a result, there is a space between the table leaves  27  and  37  to accommodate the cover plate  40 . The area of the table top is thus expanded. As shown in FIG. 10, in the event that the inner rail  20  or the outer rail  30  is damaged, the damaged rail can be easily removed and replaced with a new one by removing first the locating member  17  or  18  of the primary rail  10  so as to enable the damaged inner rail or outer rail to be removed. As shown in FIG. 11 the inner rail  20  and the outer rail  30  of the present invention may be coupled with two extension rails  50  and  60 , which are respectively provided with two fitting slots  51 ,  62 , and two fitting protrusions  52 ,  62 . The inner rail  20  and the outer rail  30  are respectively provided with a hole  28 ,  38  for locating a locating member  29 ,  39  for retaining an arresting edge  54 ,  64  of the connection plate  53 ,  63  connected with the extension rail  50 ,  60 . The extension rail  50 ,  60  is provided in the inner or outer side thereof with a connection piece  55 ,  65  riveted thereto for fastening two side plates to expand the table top area. 
     The embodiments of the present invention described above are to be regarded in all respects as being merely illustrative and not restrictive. Accordingly, the present invention may be embodied in other specific forms without deviating from the spirit thereof. The present invention is therefore to be limited only by the scopes of the following appended claims.