Chair assembly having upper and lower seat members

Abstract

A chair assembly includes a chair frame unit, an upper seat member and a lower seat member. The upper seat member is connected to the chair frame unit, and has opposing front and rear edges, and opposing lateral edges that interconnect the front and rear edges. The upper seat member is formed with an opening that extends from the front edge toward the rear edge to form the upper seat member with a U-shaped configuration. The lower seat member is disposed below the upper seat member and is registered with the opening.

I claim:  
     
         1 . A chair assembly comprising: 
 a chair frame unit;    an upper seat member connected to said chair frame unit, and having opposing front and rear edges, and opposing lateral edges that interconnect said front and rear edges, said upper seat member being formed with an opening that extends from said front edge toward said rear edge to form said upper seat member with a U-shaped configuration; and    a lower seat member disposed below said upper seat member and registered with said opening.    
     
     
         2 . The chair assembly of  claim 1 , wherein said chair frame unit includes a pair of front leg rods and a pair of rear leg rods, each of said lateral edges of said upper seat member being connected to one of said front leg rods and one of said rear leg rods.  
     
     
         3 . The chair assembly of  claim 2 , wherein each of said front leg rods has an inclined lower rod portion that extends downwardly and frontwardly relative to said upper seat member, said chair frame unit further including a connecting bar that interconnects said lower rod portions of said front leg rods and that has said lower seat member mounted securely thereon.  
     
     
         4 . The chair assembly of  claim 3 , wherein each of said front leg rods further has an inclined upper rod portion that extends upwardly and rearwardly with respect to said upper seat member, said chair frame unit further including a backrest member that is mounted on and that extends between said upper rod portions of said front leg rods.  
     
     
         5 . The chair assembly of  claim 3 , wherein each of said rear leg rods is further connected securely to a respective one of said front leg rods.  
     
     
         6 . The chair assembly of  claim 2 , wherein said front leg rods are connected pivotally and respectively to said lateral edges of said upper seat member, said chair frame unit further including: 
 a pair of first pivot links, each of which interconnects pivotally a respective one of said lateral edges of said upper seat member and a respective one of said rear leg rods; and    a pair of second pivot links, each of which interconnects pivotally a respective one of said front leg rods and a respective one of said rear leg rods.    
     
     
         7 . The chair assembly of  claim 6 , wherein each of said front leg rods has a lower rod portion that extends downwardly relative to said upper seat member, said chair frame unit further including a connecting bar that interconnects said lower rod portions of said front leg rods for supporting said lower seat member thereon.  
     
     
         8 . The chair assembly of  claim 7 , wherein said upper seat member has a lower surface, and said lower seat member has a rear edge, said chair assembly further comprising a third pivot link for interconnecting pivotally said lower surface of said upper seat member and said rear edge of said lower seat member.  
     
     
         9 . The chair assembly of  claim 1 , wherein: 
 said lower seat member has opposite lateral sides;    said upper seat member having a pair of hollow positioning rails that extend downwardly and that are respectively disposed adjacent to said lateral sides of said lower seat member, each of said positioning rails having an open side that confronts the respective one of said lateral sides of said lower seat member, and being formed with a series of positioning holes that are vertically aligned and that are spaced apart from each other;    each of said lateral sides of said lower seat member having a positioning member that extends into the adjacent one of said positioning rails via said open side, and that engages removably and selectively one of said positioning holes for retaining said lower seat member at a desired height relative to said upper seat member.    
     
     
         10 . The chair assembly of  claim 9 , wherein said positioning member includes a retaining block mounted pivotally on said lower seat member and formed with a retaining protrusion for engaging removably and selectively said positioning holes, and a biasing member for biasing said retaining block so as to ensure removable engagement between said retaining protrusion and the selected one of said positioning holes.  
     
     
         11 . The chair assembly of  claim 1 , further comprising a backrest member that extends upwardly from said rear edge of said upper seat member.  
     
     
         12 . The chair assembly of  claim 1 , wherein said chair frame unit, said upper seat member and said lower seat member are connected integrally.  
     
     
         13 . The chair assembly of  claim 12 , further comprising a backrest member connected integrally to said rear edge of said upper seat member, and two armrests connected integrally and respectively to said opposing lateral edges of said upper seat member.