Abstract:
A linking mechanism includes a rotary wheel set, a linking cord set and an actuator set s chair includes a chair body carrying a rotating wheel and coupled between a drawer cabinet and a drawer to synchronize the operation of two sliding rail assemblies that are coupled between the drawer and the drawer cabinet, enabling the drawer to be accurately moved in and out of the drawer cabinet between an open position and a close position.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to drawer and drawer cabinet mounting technology and more particularly, to a linking mechanism capable of synchronizing the operation of the two sliding rail assemblies that are coupled between a drawer and a drawer cabinet. 
     2. Description of the Related Art 
     Sliding rail assemblies are in drawer cabinets to secure drawers, enabling drawers to be moved in and out of drawer cabinets between a close position and an open position. However, if the applied force is not applied to the middle part of the front side of the drawer, the drawer may be biased. Further, Taiwan Patent M365677, equivalent to U.S. Pat. No. 8,079,653, discloses a sliding track assembly for controlling positioning of a movable object in a fixed object, for example, a drawer in a drawer cabinet, between a close position and an open position. This design of sliding track assembly is repeatedly pressable to control positioning of a positioning block in a circulating guide groove. However, if the user presses a part of the front side of the movable object (drawer) far from the midpoint between the two sliding track assemblies, only one sliding track assembly will be opened or locked. In this case, the drawer will not be opened or fully opened. Further, during application of auto-close sliding track assemblies, the drawer may be not fully closed due to large drawer clearance or uneven pulling force of spring members. 
     SUMMARY OF THE INVENTION 
     The present invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide a linking mechanism, which is capable of synchronizing the operation of two sliding rail assemblies that are coupled between a drawer and a drawer cabinet, enabling the drawer to be accurately moved in and out of the drawer cabinet between an open position and a close position. 
     To achieve this and other objects of the present invention, a linking mechanism comprises a rotary wheel set mounted at two opposite inner lateral sidewalls of a drawer cabinet, an actuator set mounted at two opposite outer lateral sidewalls of a drawer for rotating two rotary tables of the rotary wheel set, and a linking cord set coupled between two rotary tables of the rotary wheel set. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a top elevational view of a linking mechanism in accordance with the present invention. 
         FIG. 2  is an exploded view of a part of the linking mechanism in accordance with the present invention (I). 
         FIG. 3  is an exploded view of a part of the linking mechanism in accordance with the present invention (II). 
         FIG. 4  is a schematic installed view of the linking mechanism in accordance with the present invention (I). 
         FIG. 5  is a schematic installed view of the linking mechanism in accordance with the present invention (II). 
         FIG. 6  is a schematic drawing illustrating an operating status of the linking mechanism in accordance with the present invention (I). 
         FIG. 7  is a schematic drawing illustrating an operating status of the linking mechanism in accordance with the present invention (II). 
         FIG. 8  is a schematic drawing illustrating an operating status of the linking mechanism in accordance with the present invention (III). 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIGS. 1-6 , two sliding rail assemblies  7  are respectively arranged between two opposite outer lateral sidewalls of a drawer  6  and two opposite inner lateral sidewalls of a drawer cabinet  5 , and a linking mechanism in accordance with the present invention is shown coupled between the drawer  6  and the drawer cabinet  5 . Subject to the functioning of the sliding rail assemblies  7 , the drawer  6  can be moved in and out of the drawer cabinet  5  between an open position and a close position. 
     The linking mechanism comprises a wheel holder set  1 , a rotary wheel set  2 , a linking cord set  3 , and an actuator set  4 . The wheel holder set  1  comprises a first wheel holder  11 , which comprises a first pivot axle  111  and a first top cover  112  located at the top side thereof beyond the first pivot axle  111  and defining a first curved track  113 , and a second wheel holder  12 , which comprises a second pivot axle  121  and a second top cover  122  located at the top side thereof beyond the second pivot axle  121  and defining a second curved track  123 . The rotary wheel set  2  comprises a first rotary table  21  and a second rotary table  22 . The first rotary table  21  comprises a first locating portion  211  and a first connection portion  212  respectively located at opposing top and bottom sides thereof, a first driven slot  213  located at the periphery thereof between the first locating portion  211  and the first connection portion  212 , a first center pivot hole  214 , and a first rib  215  extend around one side of the first driven slot  213 . The second rotary table  22  comprises a second locating portion  221  and a second connection portion  222  respectively located at opposing top and bottom sides thereof, a second driven slot  223  located at the periphery thereof between the second locating portion  221  and the second connection portion  222 , a second center pivot hole  224 , and a second rib  225  extending around one side of the second driven slot  223 . The linking cord set  3  comprises a first linking cord  31 , a second linking cord  32 , a first tension adjustment device  33  adapted for adjustment of the tension of the first linking cord  31 , and a second tension adjustment device  34  adapted for adjustment of the tension of the second linking cord  32 . The actuator set  4  comprises a first actuator  41  and a second actuator  42 . The first actuator  41  comprises a first driving rod  411 , and a first locating plate  412 . The second actuator  42  comprises a second driving rod  421  and a second locating plate  422 . 
     The first wheel holder  11  and second wheel holder  12  of the wheel holder set  1  are respectively affixed to the two opposite inner lateral sidewalls of the drawer cabinet  5 . The first center pivot hole  214  of the first rotary table  21  is coupled to the first pivot axle  111  of the first wheel holder  11 . The second center pivot hole  224  of the second rotary table  22  is coupled to the second pivot axle  121  of the second wheel holder  12 . The linking cord set  3  is installed in the rotary wheel set  2  in such a manner that the first linking cord  31  has its one end connected to the first locating portion  211  of the first rotary table  21  and its other end extended to the second rotary table  22  and wound round the first connection portion  212  of the first rotary table  21  and the second connection portion  222  of the second rotary table  22  and then connected to the second locating portion  221 . The second linking cord  32  has its one end connected to the first connection portion  212  of the first rotary table  21 , and its other end extended toward the second rotary table  22  and then wound round the first locating portion  211  of the first rotary table  21  and the second locating portion  221  of the second rotary table  22  and then connected to the second connection portion  222  so that the first linking cord  31  and the second linking cord  32  extend across each other and coupled between the first rotary table  21  and the second rotary table  22 . The first locating plate  412  of the first actuator  41  and the second locating plate  422  and the second actuator  42  are respectively fastened to the two opposite outer lateral sidewalls of the drawer  6 , keeping the first driving rod  411  of the first actuator  41  in the first driven slot  213  of the first rotary table  21  and the second driving rod  421  of the second actuator  42  in the second driven slot  223  of the second rotary table  22 . 
     Referring to  FIGS. 7 and 8  and  FIGS. 4-6  again, when the drawer  6  is received in the drawer cabinet  5 , the first driving rod  411  of the first actuator  41  and the second driving rod  421  of the second actuator  42  are respective inserted into the first driven slot  213  of the first rotary table  21  and the second driven slot  223  of the second rotary table  22 . If the user presses a part of the front side of the drawer  6  far from the midpoint thereof, for example, the right corner area that is close to the second driving rod  421  (see the hollow arrowhead sign in  FIG. 7 ), the second driving rod  421  will be forced by the drawer  6  to push the second driven slot  223  of the second rotary table  22  and to further rotate the second rotary table  22 . During rotation of the second rotary table  22 , the second linking rod  32  will be driven to rotate the first rotary table  21  in direction reversed to the second rotary table  22  to further move the first driving rod  411  of the first actuator  41 , forcing the first actuator  41  to move the drawer  6 . Thus, the operation of the two sliding rail assemblies  7  are synchronized, enabling the drawer  6  to be fully closed. On the contrary, when the user presses the left corner area of the front side of the drawer  6  that is close to the first driving rod  411 , the first driving rod  411  will be forced by the drawer  6  to push the first driven slot  213  of the first rotary table  21  and to further rotate the first rotary table  21 . During rotation of the first rotary table  21 , the first linking rod  31  will be driven to rotate the second rotary table  22  in direction reversed to the first rotary table  21  to further move the second driving rod  421  of the second actuator  42 , forcing the second actuator  42  to move the drawer  6 . Thus, the two sliding rail assemblies  7  are synchronously unlocked, opening the drawer  6 . Further, because the first rib  215  of the first rotary table  21  is attached to the first curved track  113  of the first top cover  112  and the second rib  225  of the second rotary table  22  is movably attached to the second curved track  123  of the second top cover  122 , the angle of rotation of the first rotary table  21  and second rotary table  22  are limited to a predetermined range.