Adjustable retainer for a headrest

Abstract

A chair back supports a positionable headrest assembly including a post and headrest with the post manually positionable in a channel on the chair back. A retainer arm bears against the post to inhibit post travel against all but deliberately applied force, as for example, by a dental assistant when adjusting a dental chair to accommodate the next patient. A threaded member in the chair back is settable to apply the desired resistance to post travel during headrest adjustment. Access to the threaded member for adjustment purposes may be by an opening in the chair back normally receiving a fastener securing a chair component.

1 . In a chair having back and a headrest assembly including a headrest and post, the improvement comprising, 
 a guideway on the chair back in which the post is carried,    a retainer assembly on the chair back including an arm having a distal end, adjustable means for biasing said distal end toward the post to inhibit post movement along the guideway to enable headrest positioning relative the chair back by selected degrees of manual force.    
   
   
       2 . The improvement claimed in  claim 1  additionally including bearing of synthetic material interposed between said distal end of the arm and the post of the headrest assembly.  
   
   
       3 . The improvement claimed in  claim 1  wherein said arm has a proximal end, said guideway having a support member supporting said proximal end of the arm.  
   
   
       4 . The improvement claimed in  claim 1  wherein said adjustable means includes an adjustment screw.  
   
   
       5 . The improvement claimed in  claim 4  additionally including a cover plate on the chair back, a fastener normally extending through an opening in said cover plate and into the chair back, said fastener in axial alignment with the adjustment screw and upon fastener removal permitting access to the adjustment screw through the cover plate opening for temporary application of a tool to the adjustment screw to enable varying of the force applied to the post by said arm.  
   
   
       6 . In a chair having a back and a headrest assembly including a headrest and a post, the improvement comprising, 
 a guideway on the chair back receiving the post,    a retainer assembly including a retainer acting on the post, adjustable means for biasing the retainer towards the post to inhibit movement of the post along the guideway, and    a removable fastener normally seated in the chair back and upon fastener removal providing an opening permitting access of a tool to said adjustable means for altering the biasing force of said retainer applied to the post.    
   
   
       7 . The improvement claimed in  claim 6  wherein said retainer is an arm having a distal end proximate said post.  
   
   
       8 . The improvement claimed in  claim 7  additionally including a bearing of synthetic material interposed between said distal end of the arm and the post of the headrest assembly.  
   
   
       9 . The improvement claimed in  claim 6  wherein said guideway has a support member supporting the proximal end of the arm.  
   
   
       10 . The improvement claimed in claimed  6  wherein said adjustable means includes an adjustment screw.  
   
   
       11 . The improvement claimed in  claim 10  additionally including a cover plate on the chair back, a fastener normally extending through an opening in said cover plate and into the chair back, said fastener normally in axial alignment with the adjustment screw and upon fastener removal permitting access to the adjustment screw through the opening for temporary application of a tool to the adjustment screw to enable altering the force applied to the post by said arm and hence post resistance to travel.  
   
   
       12 . An adjustable retainer for a headrest assembly supported by the back of a chair or vehicle seat and including, 
 a guideway carried by the chair back,    a post positionable along the guideway to determine the elevation of a headrest carried by the post,    a retainer arm on the guideway proximate the post for applying a force transversely of the post to inhibit post travel along the guideway and    a threaded member in abutment with the retainer arm and axially positionable to vary the force applied to the post and hence the degree to which post travel is inhibited    
   
   
       13 . The adjustable retainer for the headrest claimed in  claim 12  additionally including a bearing member of synthetic material interposed between the post and the distal end of the retainer arm.