Adjustable leg system

Abstract

Telescoping legs having outer and inner leg members increases stability of an adjustable worktable. The outer leg member has a tubular cross section of a geometric shape to accommodate the cross section of the inner leg member so that the inner leg member fits into the outer leg member. The assembly includes one or more sets of one or more protrusions inwardly projecting from the interior surface of the outer leg member to guide the inner leg member into the outer leg member. In their locations, the protrusions serve to further minimize the gap between the outer leg member and the inner leg member of the telescoping leg assemblies, thereby further improving the stability of the adjustable table. The protrusions are made by crimping, forming, additional hardware, or through other procedures.

1 . A worktable or the like of the type having a plurality of generally upright support legs wherein a leg comprises: 
 a first member comprised of tubing having an inner surface having a regular geometric cross-sectional shape to form an outer leg member;    a second member comprising an elongated member having an outer wall having the same geometric cross-sectional shape and of a size smaller than that of the inner surface of the first member to form an inner leg member, and wherein the second member is receivable within the first member to form a telescoping leg structure;    wherein the inner surface of the outer leg member includes a pair of longitudinally spaced portions which project inwardly to closely receive the outer wall of the inner leg member to guide its longitudinal movements within the outer leg member.    
     
     
         2 . A worktable or the like, as claimed in  claim 1 , wherein the longitudinally spaced portions comprise projections which project inwardly around substantially the entire interior surface of the outer leg member.  
     
     
         3 . A worktable or the like, as claimed in  claim 1 , wherein the longitudinally spaced portions comprise projections which project inwardly around a portion of the entire interior surface of the outer leg member.  
     
     
         4 . A worktable or the like, as claimed in  claim 3:   wherein the-first member comprises malleable metal tubing having a rectangular cross-section to form an outer leg member; and    wherein the second member has a rectangular outer cross-sectional shape to form a rectangular inner leg member; and    wherein the projections on the interior surface of the outer leg member are formed by crimping the lateral walls of the malleable tubing so that the inner surface of the outer leg member closely receives the inner leg.    
     
     
         5 . A worktable or the like, as claimed in  claim 4:   wherein all four lateral walls of the outer malleable tubing leg member are crimped at a plurality of vertically spaced intervals to form projections which project inwardly around substantially the entire interior surface of the outer leg member to cause the inner surface of the outer leg member to closely receive the inner leg member and to space the outer walls of the inner leg member substantially uniformly from the inner walls of the outer leg member and to hold the inner leg member in alignment with the outer leg member.    
     
     
         6 . A worktable or the like, as claimed in  claim 1 , further comprising a releasable latch mechanism for securing the second member to the first member to prevent relative movement and to permit adjustment of the length of the leg structure.  
     
     
         7 . A worktable or the like, as claimed in  claim 4:   wherein the outer leg member has a hole through its wall;    wherein the releasable latch mechanism comprise a transverse pin mounted on the outer leg member for transverse movement through the hole in the wall of the outer leg member and a biasing mechanism for urging the pin inwardly; and    wherein the inner leg member includes a plurality of vertically aligned holes for receiving the latch mechanism pin in order to permit the length of the leg structure to be selectively adjusted.    
     
     
         8 . A worktable or the like, of the type having a plurality of generally upright support legs wherein a leg comprises: 
 a first member forming an outer leg member comprised of malleable metal tubing having an inner surface having a regular geometric cross-sectional shape with at least one substantially flat wall;    a second member forming an inner leg member having an outer wall having the same geometric cross-sectional shape and of a size smaller than that of the inner surface of the outer leg member with at least one substantially flat wall in juxtaposition with the flat wall of the outer tubing, and wherein the inner leg member is receivable within the outer leg member to form a telescoping leg structure;    wherein the inner surface of the outer leg member includes a pair of longitudinally spaced portions which are formed by crimping the lateral walls of the malleable tubing so that the inner surface of outer leg closely receives the inner leg to space the outer walls of the inner leg substantially uniformly from the inner walls of the outer leg and to hold the inner leg member in alignment with the outer leg member;    further comprising a releasable latch mechanism for securing the inner leg to the outer leg to prevent relative movement and to permit adjustment of the height of the length of the leg structure;    wherein the outer leg member has a hole through its wall;    wherein the releasable latch mechanism comprises a transverse pin mounted on the outer leg member for transverse movement through the hole in the wall of the outer leg member intermediate to the two crimped portions;    and a biasing mechanism for urging the pin inwardly; and    wherein the inner leg member includes a plurality of vertically aligned holes for receiving the latch mechanism pin in order to permit the length of the leg structure to be selectively adjusted and to further secure the inner leg within the outer leg.    
     
     
         9 . A worktable or the like, as claimed in  claim 8 , wherein the legs are rectangular in cross-section.  
     
     
         10 . A worktable or the like, as claimed in  claim 9 , wherein the inner and outer leg members are of rectangular metal tubing.  
     
     
         11 . For a portion of an article of furniture, a plurality of adjustable legs, each of the adjustable legs comprising: 
 a first longitudinal member having first and second ends and a length therebetween, the first end configured for attachment to the portion of the article of furniture, from the second end along at least part of the length the first longitudinal member being hollow having an interior being accessible through the second end, the interior having an interior surface, an interior longitudinal length and an interior cross-sectional profile taken perpendicular to the interior longitudinal length, the interior cross-sectional profile having a cross-sectional area dependant upon position from the second end along the interior longitudinal length, the cross-sectional area for one or more first sections of the interior being greater than the cross-sectional area for one or more second sections of the interior, the one or more first sections of the interior having a combined longitudinal length greater than 95% of the interior longitudinal length; and    a second longitudinal member with first and second ends and a longitudinal length and a cross-sectional profile taken perpendicular to the longitudinal length along at least a portion of the longitudinal length from the first end, the cross-sectional profile having a cross-sectional area smaller than the cross-sectional area of the one or more second sections of the interior of the first longitudinal member.    
     
     
         12 . The adjustable legs of  claim 11  wherein the first longitudinal member has the one or more first sections of the interior with a combined longitudinal length greater than 98% of the interior longitudinal length.  
     
     
         13 . The adjustable legs of  claim 11  wherein the first longitudinal member has the one or more first sections of the interior with a combined longitudinal length greater than 99% of the interior longitudinal length.  
     
     
         14 . For a table, a plurality of adjustable legs, each of the adjustable legs comprising: 
 an outer leg member having a length and an open end, the outer leg member being hollow along at least a portion of the length from the open end having an interior accessible through the open end, the interior having interior walls each having a surface, the interior walls having a total surface area and having protrusions extending from one or more of the interior wall surfaces into the interior, the protrusions extending from less than ten percent of the total surface area of the interior walls; and    an inner leg member having a length and a cross-sectional profile taken perpendicular to the length along at least a portion of the length, the cross-sectional profile shaped to fit into the open end of the outer leg member and into the interior of the outer leg member including areas of the interior having the protrusions.    
     
     
         15 . The adjustable legs of  claim 14  wherein the outer leg member has the protrusions extending from less than five percent of the total surface area of the interior walls.  
     
     
         16 . The adjustable legs of  claim 14  wherein the outer leg member has the protrusions extending from less than two percent of the total surface area of the interior walls.  
     
     
         17 . The adjustable legs of  claim 14  wherein the outer leg member has the protrusions extending from less than one percent of the total surface area of the interior walls.  
     
     
         18 . For an article of furniture, an adjustable leg comprising: 
 an inner leg member having a length, one or more external walls with external surfaces, and protrusions extending from the external wall surfaces, the protrusions extending from less than ten percent of the total surface area of the external wall surfaces; and    an outer leg member having a length and an open end, the outer leg member being hollow along at least a portion of the length from the open end having an interior accessible through the open end, the interior having a cross-sectional profile taken perpendicular to the length along at least a portion of the length, the cross-sectional profile shaped to receive the inner leg member including the protrusions of the inner leg member.    
     
     
         19 . The adjustable leg of  claim 18  wherein the inner leg member has the protrusions extending from less than five percent of the total surface area of the external wall surfaces.  
     
     
         20 . The adjustable leg of  claim 18  wherein the inner leg member has the protrusions extending from less than two percent of the total surface area of the external wall surfaces.  
     
     
         21 . The adjustable leg of  claim 18  wherein the inner leg member has the protrusions extending from less than one percent of the total surface area of the external wall surfaces.