Height adjustable chair armrest

Abstract

A height adjustable chair armrest comprises a lower tube, an upper tube, and a push member. Two circular supporting units are provided on upper and lower ends of the lower tube so that the lower tube has an exact contact with the upper tube and a smooth adjustment can be achieved. A flexible gripper secured to one side of the upper tube receives urgently a fastener provided on one side of the push member so that pressing the push member will make a first protrusion at a lower section of the push member to depart from one of a plurality of holes of the lower tube so as to adjust the height of the armrest. Meanwhile, a protrusion protrudes from an inner side of the upper tube for cooperating with a bar groove extending vertically on the lower tube to provide a smooth guide of movement of the upper tube.

1 . A height adjustable chair armrest, comprising a lower tube, an upper tube mounted on the lower tube, and a push member; wherein:
 the push member is mounted on one side of the upper tube, pressing of an upper section of the push member will make a first protrusion at a lower section of the push member to depart from one of a plurality of holes of the lower tube by compression of an elastic member so as to adjust the height of the armrest by simple operation, and releasing of the upper section of the push member will make the upper section of the push member to return to the original position by expansion of the elastic element and cause the first protrusion at the lower section of the push member to enter into one of the holes of the lower tube at the related position.   
   
   
       2 . The height adjustable chair armrest according to  claim 1 , wherein a convex member with a containing space is formed on a middle section on one side of the upper tube for receiving a flexible gripper; and said gripper is bent to form a gripping space having a narrower opening for allowing a fastener provided on one side of the push member with a wider outer section and a narrower inner section to be fitted therein so that the push member has a flexible and stable contact with the upper tube. 
   
   
       3 . The height adjustable chair armrest according to  claim 1 , wherein a restriction part having an annular groove is provided on one side of the upper tube corresponding to the push member for holding the elastic element by cooperating with a second protrusion on a recess of said push member so as to provide a stable and elastic operation for the push member. 
   
   
       4 . The height adjustable chair armrest according to  claim 1 , wherein a through hole is provided on one end of the upper tube for allowing the first protrusion of the push member to movably pass therethrough and for being coordinated with the plurality of the holes of the lower tube. 
   
   
       5 . The height adjustable chair armrest according to  claim 1 , wherein the upper tube is provided with a convex member with a containing space for receiving a flexible gripper, a restriction part on an upper end for allowing the elastic element to be stably positioned, a through hole on a lower end for allowing the first protrusion of the push member to movably pass therethrough, and a frame around the convex member, the restriction part and the through hole for allowing the push member to be mounted thereon and to be flexibly pushable. 
   
   
       6 . A height adjustable chair armrest, comprising a lower tube, an upper tube mounted on the lower tube, and a push member; wherein:
 each of upper and lower ends of the lower tube is formed with a circular groove having two spaced holes for allowing a circular supporting unit having an opening to be mounted thereon; and each end of each circular supporting unit defining the opening has an inward protrusion respectively for being inserted into one of the holes of each circular groove of the lower tube so that the lower tube has an exact contact with the upper tube and a smooth movement of the upper tube is achieved when the height adjustment of the armrest is performed.   
   
   
       7 . A height adjustable chair armrest, comprising a lower tube, an upper tube mounted on the lower tube, and a push member; wherein:
 a bar groove extends vertically on one side of the lower tube between upper and lower circular grooves for receiving a protrusion protruding from one inner side of the upper tube to provide a smooth guide of movement and a highest and lowest limit of height adjustment when the height adjustment of the armrest is performed.