Chair

Abstract

A back for an office chair comprises a peripheral frame shaped generally to outline the back of an occupant in the chair; a lumbar base structure attached to the frame; and a lumbar back support for an occupant of the chair connected to the lumbar base structure and extending toward the lumbar area of an occupant through an adjustable connection. The adjustable connection helps to provide comfort to the occupant and comprises one or more of a detent to allow adjustment of the height of the back support in relation to the frame, a movable joint to allow rotary motion of the lumbar back support in relation to movement of the back of the occupant, and an extensible connection to allow adjustment of the distance between the lumbar base structure and the lumbar back support. The chair back may also comprise at least one movable and flexible LED light supported by the back for reading comfort and may contain electrical circuitry to supply power to the LED light. The light may be removable with an electrical plug-in connection.

1 . A back for a chair comprising 
 a) a peripheral frame shaped generally to outline the back of an occupant in the chair;    b) a lumbar base structure attached to the frame; and    c) a lumbar back support for an occupant of the chair connected to the lumbar base structure and extending toward the lumbar area of an occupant through an adjustable connection;    d) the adjustable connection comprising a detent to allow adjustment of the height of the back support in relation to the frame, a movable joint to allow rotary motion of the lumbar back support in relation to movement of the back of the occupant, and an extensible connection to allow adjustment of the distance between the lumbar base structure and the lumbar back support.    
   
   
       2 . The back for a chair of  claim 1  in which the lumbar base structure is mounted to the frame by a central vertical post and at least one pair of arms extending from the post in opposite directions and attached to the frame.  
   
   
       3 . The back for a chair of  claim 2  in which two pairs of arms extend from the vertical post and are attached to the frame.  
   
   
       4 . The back for a chair of  claim 2  in which the post is adjustable in height to allow adjustment of the size of the frame.  
   
   
       5 . The back for a chair of  claim 1  in which a headrest is located above the frame and is attached removably to the back.  
   
   
       6 . The back for a chair of  claim 5  in which the headrest has a central portion and opposing adjustable wings on either side of the central portion.  
   
   
       7 . The back for a chair of  claim 1  in which the back comprises at least one LED light supported by the back and contains electrical circuitry to supply power to the LED light.  
   
   
       8 . The back of  claim 1  in which the detent comprises a series of partial holes with intervening channels having a width less than the diameter of the holes and a spring biased cylinder having a cylindrical portion which fits in the partial holes and prevents vertical movement unless the spring biased cylinder is moved out of the holes.  
   
   
       9 . The back of  claim 1  in which the movable joint comprises a partial ball attached to the back of the lumbar support and mated with a socket contained in the adjustable connection which mates with the partial ball.  
   
   
       10 . The back of  claim 1  in which the extensible connection comprises two sleeves with one sleeve sliding in the other to extend or retract in response to rotation of a bolt threaded through the sleeve closer to the lumbar back support.