Collapsible swivel chair

Abstract

A collapsible swivel chair ( 10 ) having an upper frame assembly ( 32 ), a lower frame assembly ( 34 ), and a swivel assembly ( 28 ) which joins the upper frame assembly ( 32 ) and the lower frame assembly ( 34 ). The swivel assembly ( 28 ) includes an upper plate ( 36 ) having a number of sockets ( 46 ). The sockets ( 46 ) include pivots ( 48 ) for pivotal attachment of members ( 54, 56 ) of an upper frame assembly ( 32 ). The swivel assembly ( 28 ) also includes a lower plate ( 38 ) having a plurality of sockets ( 46 ), which including pivots ( 48 ) for pivotal attachment of members ( 24 ) of a lower frame assembly ( 34 ). The upper plate ( 36 ) and the lower plate ( 38 ) are rotatably attached to each other such that the upper plate ( 36 ) and the upper frame assembly ( 32 ) can be swiveled in relation to the lower plate ( 38 ) and the lower frame assembly ( 34 ). Also a swivel assembly ( 28 ) for use in a collapsible swivel chair ( 10 ).

What is claimed is:  
     
         1 . A collapsible swivel chair comprising: 
 an upper frame assembly;    a lower frame assembly; and    a swivel assembly which joins said upper frame assembly, said swivel assembly including an upper plate which includes a plurality of pivots for pivotal attachment of members of an upper frame assembly, and a lower plate which includes a plurality of pivots for pivotal attachment of members of a lower frame assembly, said upper plate and said lower plate being rotatably attached to each other such that said upper plate and said upper frame assembly can be swiveled in relation to said lower plate and said lower frame assembly.    
     
     
         2 . A collapsible swivel chair as in  claim 1 , wherein: 
 said upper and lower plates include a plurality of guide slots, said pivots being positioned within said guide slots, said pivots each establishing a pivot axis.    
     
     
         3 . A collapsible swivel chair as in  claim 2 , wherein: 
 said upper and lower plates include a center of rotation and said pivot axes lie at a right angle to a radial extension line from said center of rotation, such that pivotal motion of the frame members as they collapse follow a path substantially along a radial extension line.    
     
     
         4 . A collapsible swivel chair as in  claim 2 , wherein: 
 said guide slots include a stop portion which limits pivotal travel of said frame members at the limits of travel in the extended position.    
     
     
         5 . A collapsible swivel chair as in  claim 1 , wherein: 
 said upper and lower plates are attached by a ball bearing mechanism to enable rotation between said upper plate and said lower plate.    
     
     
         6 . A collapsible swivel chair as in  claim 1 , wherein: 
 said upper frame assembly includes four members and said lower frame assembly includes four members.    
     
     
         7 . A collapsible swivel chair as in  claim 1 , wherein: 
 said upper and lower plates are configured to be interchangeable.    
     
     
         8 . A collapsible swivel chair as in  claim 1 , wherein: 
 said upper frame assembly includes four members and said lower frame assembly includes five members.    
     
     
         9 . A collapsible swivel chair as in  claim 1 , wherein: 
 frame members are positioned in radial arrangement and follow substantially radial paths in movement between a collapsed configuration and an extended configuration.    
     
     
         10 . A swivel assembly for a collapsible swivel chair comprising: 
 an upper plate, including a plurality of sockets, said sockets including pivots for pivotal attachment of members of an upper frame assembly; and    a lower plate, including a plurality of sockets, said sockets including pivots for pivotal attachment of members of a lower frame assembly;    said upper plate and said lower plate being rotatably attached to each other such that said upper plate and said upper frame assembly can be swiveled in relation to said lower plate and said lower frame assembly.    
     
     
         11 . A swivel assembly as in  claim 10 , wherein: 
 said upper and lower plates include a plurality of guide slots, said pivots being positioned within said guide slots, said pivots each establishing a pivot axis.    
     
     
         12 . A swivel assembly as in  claim 11 , wherein: 
 said upper and lower plates include a center of rotation and said pivot axes lie at a right angle to a radial extension line from said center, such that pivotal motion of the frame members as they collapse follow a path substantially along a radial extension line.    
     
     
         13 . A swivel assembly as in  claim 11 , wherein said guide slots include a stop portion which limits pivotal travel of said frame members at the limits of travel in the extended position.  
     
     
         14 . A swivel assembly as in  claim 10 , wherein said upper and lower plates are attached by a ball bearing mechanism to enable rotation between said upper plate and said lower plate.  
     
     
         15 . A swivel assembly as in  claim 10 , wherein: 
 said upper frame assembly includes four members and said lower frame assembly includes four members.    
     
     
         16 . A swivel assembly as in  claim 10 , wherein: 
 said upper and lower plates are configured to be interchangeable.    
     
     
         17 . A swivel assembly as in  claim 10 , wherein: 
 said upper frame assembly includes four members and said lower frame assembly includes five members.    
     
     
         18 . A swivel assembly as in  claim 10 , wherein: 
 frame members are positioned in radial arrangement and follow substantially radial paths in movement between a collapsed configuration and an extended configuration.