Chair with recline control mechanism, recline limit control and back tilt mechanism

Abstract

A chair having a recline control mechanism, a limit control apparatus and a tilt mechanism. The recline control mechanism operates to adjust resistance to rotation of a back assembly of the chair and includes an actuator lever having a lock structure attached to a movable spring assembly. Moving the spring assembly toward and away from a rotation axis for the back assembly adjusts the resistance. The limit control apparatus selectively limits the extent of rotation of the back assembly from about zero degrees to about 3.5 degrees to about seven degrees by using abutment surfaces. The tilt mechanism provides an independent and stable yet passive tilt capability to a backrest of the back assembly by using a pair of brackets, two pairs of links and two pairs of rods.

1 . A chair with a reclining back comprising: 
 a seat assembly;    a back assembly including a frame member connected to said seat assembly;    a pivot forming structure defining an axis of rotation for allowing said back assembly to rotate relative to said seat assembly; and    a biasing structure for resisting the rotation of said back assembly, said biasing structure being spaced from said axis of rotation of said back assembly and being movable forwardly toward said axis of rotation and rearwardly away from said axis of rotation for controlling resistance to rotation of said back assembly.    
     
     
         2 . The chair of  claim 1  including: 
 an actuator structure connected to said biasing structure for moving said biasing structure.    
     
     
         3 . The chair of  claim 1  including: 
 a lock structure connected to said biasing structure for locking said biasing structure in a selected position.    
     
     
         4 . The chair of  claim 1  including: 
 a lock structure connected to said biasing structure for locking said biasing structure in a selected position; and    an actuator structure connected to said biasing structure and to said lock structure for selectively locking and unlocking said lock structure and for moving said biasing structure.    
     
     
         5 . The chair of  claim 1  wherein: 
 said pivot forming structure includes a lower mount and an upper mount.    
     
     
         6 . The chair of  claim 1  wherein: 
 said biasing structure includes a spring.    
     
     
         7 . The chair of  claim 1  including: 
 a lock structure connected to said biasing structure for locking said biasing structure in a selected position; and    an actuator structure connected to said biasing structure and to said lock structure for selectively locking and unlocking said lock structure and for moving said biasing structure; and wherein    said pivot forming structure includes a lower mount and an upper mount.    
     
     
         8 . The chair of  claim 7  wherein: 
 said biasing structure includes a spring.    
     
     
         9 . The chair of  claim 1  including: 
 a limit control apparatus connected to said back assembly and to said pivot forming structure for limiting recline of said back assembly.    
     
     
         10 . The chair of  claim 9  wherein: 
 said limit control apparatus includes a first structure having a stepped configuration with a plurality of abutment surfaces, each of said abutment surfaces being disposed in a generally horizontal attitude, said first structure being connected to either a chair lower mount or to the reclining back assembly;    a second structure including an abutment surface for selectively engaging said abutment surfaces of said first structure, said abutment surface of said second structure being disposed in a generally horizontal attitude; and    an actuator structure being connected either to said first structure or to said second structure for controlling engagement of said first and said second structures.    
     
     
         11 . The chair of  claim 10  wherein: 
 said actuator structure is rotatable about a generally vertical axis; and    said second structure slides linearly in response to movement of said actuator structure.    
     
     
         12 . The chair of  claim 11  wherein: 
 said second structure includes a projection forming said abutment surface, a slidable base for mounting said projection and a post connected to said base and to said actuator structure.    
     
     
         13 . The chair of  claim 12  wherein: 
 said second structure is mounted to a chair lower mount and said first structure is mounted to said back assembly.    
     
     
         14 . The chair of  claim 1  wherein: 
 said back assembly includes a tilt mechanism for maintaining said back assembly in contact with a chair user during recline of said back assembly.    
     
     
         15 . The chair of  claim 14  wherein: 
 said tilt mechanism includes a first bracket affixed to a frame member that is part of said back assembly, said first bracket having a first pair of holes and a second pair of holes;    a second bracket pivotally mounted to said first bracket and affixed to a back of said back assembly, said second bracket having a first pair of holes and a second pair of holes;    a first pair of links, each link of said first pair of links having first and second end portions;    a second pair of links, each link of said second pair of links having first and second end portions;    a first structure for pivotally connecting said first bracket through said first pair of holes and said first end portions of said first pair of links;    a second structure for pivotally connecting said second bracket through said first pair of holes and said second end portions of said first pair of links;    a third structure for pivotally connecting said first bracket through said second pair of holes and said first end portions of said second pair of links; and    a fourth structure for pivotally connecting said second bracket through said second pair of holes and said second end portions of said second pair of links.    
     
     
         16 . The chair of  claim 15  wherein: 
 said first structure includes a first rod;    said second structure includes a second rod;    said third structure include a third rod; and    said fourth structure includes a fourth rod.    
     
     
         17 . The chair of  claim 16  wherein: 
 said first rod is mounted in said first pair of holes of said first bracket and in holes of said first end portions of said first pair of links;    said second rod is mounted to holes in said second end portions of said first pair of links and in said first pair of holes of said second bracket;    said third rod is mounted in said second pair of holes of said first bracket and to holes in said first end portions of said second pair of links; and    said fourth rod is mounted to holes in said second end portions of said second pair of links and in said second pair of holes of said second bracket.    
     
     
         18 . The chair of  claim 9  including: 
 a tilt mechanism for maintaining said back assembly in contact with a chair user during recline of said back assembly.    
     
     
         19 . The chair of  claim 18  wherein: 
 said tilt mechanism includes a first bracket affixed to a frame member that is part of said chair back assembly, said first bracket having a first pair of holes and a second pair of holes;    a second bracket pivotally mounted to said first bracket and affixed to a back of said back assembly, said second bracket having a first pair of holes and a second pair of holes;    a first pair of links, each link of said first pair of links having first and second end portions;    a second pair of links, each link of said second pair of links having first and second end portions;    a first structure for pivotally connecting said first bracket through said first pair of holes and said first end portions of said first pair of links;    a second structure for pivotally connecting said second bracket through said first pair of holes and said second end portions of said first pair of links;    a third structure for pivotally connecting said first bracket through said second pair of holes and said first end portions of said second pair of links; and    a fourth structure for pivotally connecting said second bracket through said second pair of holes and said second end portions of said second pair of links.    
     
     
         20 . The chair of  claim 19  wherein: 
 said first structure includes a first rod;    said second structure includes a second rod;    said third structure include a third rod; and    said fourth structure includes a fourth rod.    
     
     
         21 . A limit control apparatus for a reclining back assembly of a chair comprising: 
 a first structure having a stepped configuration with a plurality of abutment surfaces, each of said abutment surfaces being disposed in a generally horizontal attitude, said first structure being connected to either a chair lower mount or to the reclining back assembly;    a second structure including an abutment surface for selectively engaging said abutment surfaces of said first structure, said abutment surface of said second structure being disposed in a generally horizontal attitude; and    an actuator structure being connected either to said first structure or to said second structure for controlling engagement of said first and said second structures.    
     
     
         22 . The apparatus of  claim 21  wherein: 
 said actuator structure is rotatable about a generally vertical axis; and    said second structure slides linearly in response to movement of said actuator structure.    
     
     
         23 . The apparatus of  claim 22  wherein: 
 said actuator structure includes a handle and a link, said link having a first end portion pivotally connected to said handle and a second end portion having a slot for pivotal engagement with said second structure.    
     
     
         24 . The apparatus of  claim 23  wherein: 
 said second structure is mounted to a chair lower mount and said first structure is mounted to the back assembly.    
     
     
         25 . The apparatus of  claim 21  wherein: 
 said second structure includes a projection forming said abutment surface, a slidable base for mounting said projection and a post connected to said base and to said actuator structure.    
     
     
         26 . The apparatus of  claim 21  wherein: 
 said actuator structure is rotatable about a generally vertical axis;    said second structure slides linearly in response to movement of said actuator structure; and    said second structure includes a projection forming said abutment surface, a base for mounting said projection and a post connected to said base and to said actuator structure.    
     
     
         27 . The apparatus of  claim 26  wherein: 
 said second structure is connected to a lower mount and said first structure is mounted to the back assembly.    
     
     
         28 . A tilt mechanism for a chair back comprising: 
 a first bracket adapted to be affixed to a chair frame member that supports the chair back, said first bracket having a first pair of holes and a second pair of holes;    a second bracket pivotally movably mounted to said first bracket adapted to be affixed to the chair back, said second bracket having a first pair of holes and a second pair of holes;    a first pair of links, each link of said first pair of links having first and second end portions;    a second pair of links, each link of said second pair of links having first and second end portions;    a first structure for pivotally connecting said first bracket through said first pair of holes and said first end portions of first pair of links;    a second structure for pivotally connecting said second bracket through said first pair of holes and said second end portions of said first pair of links;    a third structure for pivotally connecting said first bracket through said second pair of holes and said first end portion of said second pair of links; and    a fourth structure for pivotally connecting said second bracket through said second pair of holes and said second end portions of said second pair of links.    
     
     
         29 . The tilt mechanism of  claim 28  wherein: 
 said first structure includes a first rod;    said second structure includes a second rod;    said third structure includes a third rod; and    said fourth structure includes a fourth rod.    
     
     
         30 . The tilt mechanism of  claim 29  wherein: 
 said second bracket is restricted to move in a two-dimensional plane generally perpendicular to longitudinal axes of said first, said second, said third and said fourth rods.