Swivel arm adjustment

Abstract

A swivel arm adjustment device is provided for pivoting the armrest of a chair in order to allow multi-position adjustment to relieve stresses normally exerted on hands and wrists from improper hand positioning when typing. The swivel arm adjustment device includes a top member and a base member. The top member has a unitized construction and includes a centralized aperture, a first arcuate slot with resistance grooves and a second arcuate slot. The base member also has a unitized construction and includes a bushing with a snap-lock ring and a detent pin. The base and top members are adapted to be snapped together to form a pivotal coupling. The swivel arm adjustment device pivotally connects the armrest to the arm of a chair to provide a pivotal arrangement.

What is claimed is:  
     
         1 . A swivel armrest adjustment for a chair comprising: 
 a base member pivotally connected to a top;    a detent pin extending from said base member;    a bushing also extending from said base member;    a locking ring formed on said bushing and adapted to secure said base member in locking pivotal engagement with said top member;    an aperture formed on said top member and adapted to receive said bushing;    an annular ridge formed on said aperture and adapted to secure said bushing; and    an arcuate slot also formed in said top member and adapted to receive said detent pin, whereby pivotal rotation of the armrest is accomplished by pivotal movement of said top member around said bushing of said base member.    
     
     
         2 . A swivel armrest adjustment according to  claim 1 , wherein said bottom member, said detent pin, said bushing and said locking ring comprising a single, unitary piece formed of plastic.  
     
     
         3 . A swivel armrest adjustment according to  claim 1 , wherein said top member comprising a single, unitary piece formed of plastic.  
     
     
         4 . A swivel armrest adjustment according to  claim 1 , including one or more resistance grooves formed on an inner wall of said arcuate slot, each groove adapted to releasably engage said detent pin thereby providing one or more predetermined positions for securing said armrest with respect to said base member.  
     
     
         5 . A swivel armrest adjustment according to  claim 4 , wherein said top member includes a second arcuate slot that allows movement of said detent pin between said resistance grooves by allowing a wall of said arcuate slot to deform.  
     
     
         6 . The swivel armrest adjustment according to  claim 1 , wherein said top member includes a plurality of apertures to allow for connection to an armrest pad by means of fasteners.  
     
     
         7 . The swivel armrest adjustment according to  claim 1 , wherein said bottom member includes a plurality of apertures to allow for the attachment of fasteners for connection to a vertical arm of the chair.  
     
     
         8 . The swivel armrest of  claim 1  in which said base member and said top member can be snapped together as a subassembly by inserting said bushing thru said aperture and said detent pin thru said arcuate, slot and forcing said locking ring past said annular ridge thereby securing said base member and said top member together while providing for pivotal rotation of one with respect to the other within predetermined limits.  
     
     
         9 . The swivel armrest adjustment according to  claim 1 , wherein said bottom member includes a plurality of notches sized to allow for the passage of fasteners.  
     
     
         10 . The swivel armrest adjustment according to  claim 1 , wherein said bottom member includes raised ribbing to increase resistance to flexing.  
     
     
         11 . A swivel armrest adjustment for a chair comprising: 
 a top member;    an aperture formed in said top member;    a first and a second arcuate slot also formed in said top member;    a base member;    a bushing extending from said base member;    a detent pin also extending from said base member;    said aperture adapted to receive said bushing form a locking pivotal connection;    whereby pivotal rotation of the armrest is accomplished by pivotal movement of said top member around said bushing of said base member.