Laterally adjustable armrest assembly

Abstract

An adjustable armrest assembly for a bariatric chair is provided. The adjustable armrest assembly for a chair, the armrest assembly comprises: a stationary linkage which is connectable to the chair; an armrest member for supporting an arm of an individual when seated in the chair; a coupling member coupling the armrest member to the stationary linkage, the coupling member permitting travel of the armrest member relative to the stationary linkage; and, a locking element configured for acting on the coupling member to effect locking of the armrest member in any one of at least three indexed positions relative to the stationary linkage.

1 . An adjustable armrest assembly for a chair, the armrest assembly comprising: 
 a stationary linkage which is connectable to the chair;    an armrest member for supporting an arm of an individual when seated in the chair;    a coupling member effecting coupling of the armrest member to the stationary linkage, the coupling member permitting travel of the armrest member relative to the stationary linkage; and,    a locking element configured for acting on the coupling member to effect locking of the armrest member in any one of at least three indexed positions relative to the stationary linkage.    
   
   
       2 . The adjustable armrest assembly as claimed in  claim 1 , wherein the permitted travel of the armrest member relative to the stationary linkage is along an arc-like path.  
   
   
       3 . The adjustable armrest assembly as claimed in  claim 2 , wherein the coupling member is a swivel linkage.  
   
   
       4 . The adjustable armrest assembly as claimed in  claim 3 , wherein the swivel linkage comprises a stationary linkage coupling portion and an armrest coupling portion, the stationary linkage coupling portion being offset from the armrest coupling portion, the stationary linkage coupling portion further being rotatably coupled to the stationary linkage, thereby permitting rotatable movement of the swivel linkage relative to the stationary linkage, and the armrest coupling portion being rotatably coupled to the armrest member, thereby permitting rotatable movement of the swivel linkage relative to the armrest member.  
   
   
       5 . The adjustable armrest assembly as claimed in  claim 4 , wherein the armrest member includes an armrest coupling linkage for effecting the rotatable coupling to the swivel linkage, and wherein the locking element includes a detent pin which is biased to interfere with the relative rotational movement between the swivel linkage and the armrest coupling linkage, such that locking in an indexed position is effected by the detent pin being positioned in both a swivel linkage hole provided in the swivel linkage and in a respective armrest coupling hole provided in the armrest coupling linkage, the detent pin becoming so positioned when the swivel linkage hole and the respective armrest coupling linkage hole are disposed in an overlapping relationship, the swivel linkage hole and the respective armrest coupling linkage hole becoming so disposed upon relative rotational movement between the swivel linkage and the armrest coupling linkage.  
   
   
       6 . The armrest assembly as claimed in  claim 5 , wherein the locking element is coupled to one of the swivel linkage and the armrest coupling linkage.  
   
   
       7 . The adjustable armrest as claimed in  claim 1 , further comprising a threaded handwheel configured for acting on the coupling member and effecting locking of the armrest member in positions other than the at least three indexed positions.  
   
   
       8 . An armrest assembly for a chair, the armrest assembly comprising: 
 a stationary linkage configured for coupling to the chair;    an armrest member including an upper surface configured for supporting at least a portion of a forearm of a person when seated in the chair, wherein the upper surface includes an uppermost surface portion;    at least two swivel linkages effecting coupling of the armrest member to the stationary linkage, each of the at least two swivel linkages including a respective stationary linkage coupling portion rotatably coupled to the stationary linkage for rotation about a respective swivel linkage-stationary linkage axis, and also including a respective armrest member coupling portion rotatably coupled to the armrest member for rotation about a respective swivel linkage-armrest member axis;    wherein each of the at least two swivel linkages is characterized by a respective offset distance, wherein the respective offset distance is the distance between the respective swivel linkage-stationary linkage axis and the respective swivel linkage-armrest member axis in a plane which is tangent to the uppermost surface portion;    wherein the at least two swivel linkages includes a most forwardly disposed swivel linkage, such that the swivel linkage-stationary linkage axis of the most forwardly disposed linkage is forwardly disposed relative to the respective swivel linkage-stationary linkage axis of each of the other of the at least two swivel linkages and the swivel linkage-armrest member axis of the most forwardly disposed linkage is forwardly disposed relative to the respective swivel linkage-armrest member axis of each of the other of the at least two swivel linkages;    wherein the at least two swivel linkages also includes a most rearwardly disposed swivel linkage, such that the swivel linkage-stationary linkage axis of the most rearwardly disposed swivel linkage is rearwardly disposed relative to the respective swivel linkage-stationary linkage axis of each of the other of the at least two swivel linkages and the swivel linkage-armrest member axis of the most rearwardly disposed swivel linkage is rearwardly disposed relative to the respective swivel linkage-armrest member axis of each of the other of the at least two swivel linkages; and    wherein the most forwardly disposed swivel linkage has a respective offset distance which is at least 1.2 times longer than the respective offset distance of the most rearwardly disposed swivel linkage.    
   
   
       9 . The armrest assembly as claimed in  claim 8 , wherein the most forwardly disposed swivel linkage has a respective offset distance which is at least 1.5 times longer than the respective offset distance of the most rearwardly disposed swivel linkage.  
   
   
       10 . The armrest assembly as claimed in  claim 8 , wherein the most forwardly disposed swivel linkage has a respective offset distance which is at least 2 times longer than the respective offset distance of the most rearwardly disposed swivel linkage.  
   
   
       11 . An armrest assembly for a chair, the armrest assembly comprising: 
 a stationary linkage configured for coupling to the chair;    an armrest member including an upper surface configured for supporting at least a portion of a forearm of a person seated in the chair, wherein the upper surface includes an uppermost armrest surface portion;    at least two swivel linkages effecting coupling of the armrest member to the stationary linkage, each of the at least two swivel linkages including a respective stationary linkage coupling portion rotatably coupled to the stationary linkage for rotation about a respective swivel linkage-stationary linkage axis, and also including a respective armrest member coupling portion rotatably coupled to the armrest member for rotation about a respective swivel linkage-armrest member axis;    wherein each of the at least two swivel linkages is characterized by a respective offset distance, wherein the respective offset distance is the distance between the respective swivel linkage-stationary linkage axis and the respective swivel linkage-armrest member axis in a plane which is tangent to the uppermost surface portion;    wherein the at least two swivel linkages includes a most forwardly disposed swivel linkage and a most rearwardly disposed swivel linkage; and    wherein the most forwardly disposed swivel linkage has a respective offset distance which is at least 1.2 times longer than the respective offset distance of the most rearwardly disposed swivel linkage.    
   
   
       12 . The armrest assembly as claimed in  claim 11 , wherein the most forwardly disposed swivel linkage has a respective offset distance which is at least 1.5 times longer than the respective offset distance of the most rearwardly disposed swivel linkage.  
   
   
       13 . The armrest assembly as claimed in  claim 11 , wherein the most forwardly disposed swivel linkage has a respective horizontal offset distance which is at least 2 times longer than the respective horizontal offset distance of the most rearwardly disposed swivel linkage.  
   
   
       14 . A chair comprising: 
 a chair frame; and    an armrest assembly including: 
 a stationary linkage coupled to the chair frame;  
 an armrest member including an upper surface configured for supporting at least a portion of a forearm of a person seated in the chair, wherein the upper surface includes an uppermost surface portion;  
 at least two swivel linkages effecting coupling of the armrest member to the stationary linkage, each of the at least two swivel linkages including a respective stationary linkage coupling portion rotatably coupled to the stationary linkage for rotation about a respective swivel linkage-stationary linkage axis, and also including a respective armrest member coupling portion rotatably coupled to the armrest member for rotation about a respective swivel linkage-armrest member axis;  
   wherein each of the at least two swivel linkages is characterized by a respective offset distance, wherein the respective offset distance is the distance between the respective swivel linkage-stationary linkage axis and the respective swivel linkage-armrest member axis in a plane which is tangent to the uppermost surface portion;    wherein the at least two swivel linkages includes a most forwardly disposed swivel linkage, such that the swivel linkage-stationary linkage axis of the most forwardly disposed linkage is forwardly disposed relative to the respective swivel linkage-stationary linkage axis of each of the other of the at least two swivel linkages and the swivel linkage-armrest member axis of the most forwardly disposed linkage is forwardly disposed relative to the respective swivel linkage-armrest member axis of each of the other of the at least two swivel linkages;    wherein the at least two swivel linkages also includes a most rearwardly disposed swivel linkage, such that the swivel linkage-stationary linkage axis of the most rearwardly disposed swivel linkage is rearwardly disposed relative to the respective swivel linkage-stationary linkage axis of each of the other of the at least two swivel linkages and the swivel linkage-armrest member axis of the most rearwardly disposed swivel linkage is rearwardly disposed relative to the respective swivel linkage-armrest member axis of each of the other of the at least two swivel linkages; and    wherein the most forwardly disposed swivel linkage has a respective offset distance which is at least 1.2 times longer than the respective offset distance of the most rearwardly disposed swivel linkage.    
   
   
       15 . The chair as claimed in  claim 14 , wherein the most forwardly disposed swivel linkage has a respective offset distance which is at least 1.5 times longer than the respective offset distance of the most rearwardly disposed swivel linkage.  
   
   
       16 . The chair as claimed in  claim 14 , wherein the most forwardly disposed swivel linkage has a respective offset distance which is at least 2 times longer than the respective offset distance of the most rearwardly disposed swivel linkage.  
   
   
       17 . A chair comprising: 
 a chair frame; and    an armrest assembly including: 
 a stationary linkage coupled to the chair frame;  
 an armrest member including an upper surface configured for supporting at least a portion of a forearm of a person seated in the chair, wherein the upper surface includes an uppermost surface portion;  
 at least two swivel linkages effecting coupling of the armrest member to the stationary linkage, each of the at least two swivel linkages including a respective stationary linkage coupling portion rotatably coupled to the stationary linkage for rotation about a respective swivel linkage-stationary linkage axis, and also including a respective armrest member coupling portion rotatably coupled to the armrest member for rotation about a respective swivel linkage-armrest member axis;  
   wherein each of the at least two swivel linkages is characterized by a respective offset distance, wherein the respective offset distance is the distance between the respective swivel linkage-stationary linkage axis and the respective swivel linkage-armrest member axis in a plane which is tangent to the uppermost surface portion;    wherein the at least two swivel linkages includes a most forwardly disposed swivel linkage and a most rearwardly disposed swivel linkage; and    wherein the most forwardly disposed swivel linkage has a respective offset distance which is at least 1.2 times longer than the respective offset distance of the most rearwardly disposed swivel linkage.    
   
   
       18 . The chair as claimed in  claim 17 , wherein the most forwardly disposed swivel linkage has a respective offset distance which is at least 1.5 times longer than the respective offset distance of the most rearwardly disposed swivel linkage.  
   
   
       19 . The chair as claimed in  claim 17 , wherein the most forwardly disposed swivel linkage has a respective horizontal offset distance which is at least 2 times longer than the respective horizontal offset distance of the most rearwardly disposed swivel linkage.