U-clip and assembly system

Abstract

A clip fastener includes a first side wall, a second side wall, and a U-shaped recess between the first side wall and second side wall. The first side wall is higher than the second side wall. The recess is at least partially defined by a surface including a first portion having relatively greater radius of curvature in the vicinity of the second side wall, a second portion having a relatively lesser radius of curvature in the vicinity of the first side wall, and an inwardly projecting ridge, said second portion and ridge at least partially defining a pocket region.

What is claimed is:  
     
         1 . A clip fastener comprising: 
 a first side wall, a second side wall, and a U-shaped recess between the first side wall and second side wall, wherein the first side wall is higher than the second side wall, and wherein the recess is at least partially defined by a surface including a first portion having relatively greater radius of curvature in the vicinity of the second side wall, a second portion having a relatively lesser radius of curvature in the vicinity of the first side wall, and an inwardly projecting ridge, said second portion and ridge at least partially defining a pocket region.    
     
     
         2 . The clip fastener of  claim 1  wherein the clip fastener is a monolithic, single piece member fabricated from a material selected from the group consisting of aluminum, aluminum-magnesium alloy, stainless steel, brass, polycarbonate nylon, polyvinyl chloride, acetal, (meth)acrylate polymer and polysulfone.  
     
     
         3 . The clip fastener of  claim 1  wherein the first side wall and second side wall are substantially parallel to each other and on opposite sides of the clip fastener.  
     
     
         4 . The clip fastener of  claim 3  wherein the first side wall has a height H 1  and the second side wall has a height H 2  and the ratio H 1 /H 2  ranges from about 0.85 to 0.95.  
     
     
         5 . The clip fastener of  claim 1  wherein the first portion of the recess surface has a radius of curvature R 1  and the second portion of the recess surface has a radius of curvature R 2  wherein the ratio R 1 /R 2  ranges from about 3.0 to about 4.0.  
     
     
         6 . The clip fastener of  claim 1  wherein the clip fastener has a width W, and the clip fastener further includes at least a lengthwise extending first hole having a diameter D wherein the ratio of D/W ranges from about 0.25 to about 0.27.  
     
     
         7 . The clip fastener of  claim 6  further including a second hole parallel to the first hole and having the same diameter as the first hole, said second hole being laterally spaced apart from the first hole.  
     
     
         8 . The clip fastener of  claim 1  further including a bottom surface having a lengthwise extending concavity.  
     
     
         9 . The clip fastener of  claim 1  wherein the first side wall has a height H 1  and the clip fastener has a width W, wherein the ratio of H 1 /W ranges from about 1.2 to about 1.3.  
     
     
         10 . A structure comprising: 
 a) at least one frame and at least first and second linear members;    b) at least one U-clip fastener fixedly attached to the first linear member, the U-clip fastener being configured and dimensioned so as to engage the second linear member, said U-clip fastener including, 
 a first side wall, a second side wall, and a U-shaped recess between the first side wall and second side wall, wherein the first side wall is higher than the second side wall, and wherein the recess is at least partially defined by a surface including a first portion having relatively greater radius of curvature in the vicinity of the second side wall, a second portion having a relatively lesser radius of curvature in the vicinity of the first side wall, and an inwardly projecting ridge, said second portion and ridge at least partially defining a pocket region for receiving the second linear member.  
   
     
     
         11 . The structure of  claim 10  wherein said structure comprises a chair.  
     
     
         12 . The structure of  claim 11  wherein the chair has a support frame and a seat member, the seat member including a seat frame and a body support, wherein the support frame includes at least first and second lateral support frame crosspieces and the seat frame includes at least first and second seat frame crosspieces, each of the first and second support frame crosspieces having attached thereto at least one said U-clip fastener for engaging a respective seat frame crosspiece.  
     
     
         13 . The structure of  claim 10  wherein the U-clip fastener is a monolithic, single piece member fabricated from a material selected from the group consisting of aluminum, aluminum-magnesium alloy, stainless steel, brass, polycarbonate nylon, polyvinyl chloride, acetal, (meth)acrylate polymer and polysulfone.  
     
     
         14 . The structure of  claim 10  wherein the first side wall and second side wall of the U-clip fastener are substantially parallel to each other and on opposite sides of the clip fastener.  
     
     
         15 . The structure of  claim 14  wherein the first side wall has a height H 1  and the second side wall has a height H 2  and the ratio H 1 /H 2  ranges from about 0.85 to 0.95.  
     
     
         16 . The structure of  claim 10  wherein the first portion of the recess surface of the U-clip fastener has a radius of curvature R 1  and the second portion of the recess surface has a radius of curvature R 2  wherein the ratio R 1 /R 2  ranges from about 3.0 to about 4.0.  
     
     
         17 . The structure of  claim 10  wherein the U-clip fastener has a width W, and the U-clip fastener further includes at least a lengthwise extending first hole having a diameter D wherein the ratio of D/W ranges from about 0.25 to about 0.27.  
     
     
         18 . The structure of  claim 17  wherein the U-clip fastener further includes a second hole parallel to the first hole and having the same diameter as the first hole, said second hole being laterally spaced apart from the first hole.  
     
     
         19 . The structure of  claim 10  wherein the U-clip fastener further includes a bottom surface having a lengthwise extending concavity dimensioned and configured to engage the first linear member.  
     
     
         20 . The structure of  claim 10  wherein the first side wall of the U-clip fastener has a height H 1  and the U-clip fastener has a width W, wherein the ratio of H 1 /W ranges from about 1.2 to about 1.3.