Patent ID: 7419219

Claim:
An adjustable arm assembly for a chair having a seat, a back rest, and a frame by which said adjustable arm assembly is positionable relative to the seat and back rest, said adjustable arm assembly comprising: an adjustable arm; a lock actuator to be operated in order to permit said adjustable arm to be changed from one elevation to another; an elevation adjustment member interconnected to said adjustable arm; a hollow elevation adjustment guide in which to slidably receive said elevation adjustment member; a lock communicating with said lock actuator, said lock engaging said hollow elevation adjustment guide when said lock actuator is not being operated to releasably retain said elevation adjustment member within said adjustment guide, whereby to prevent an elevation change of said adjustable arm, and said lock moving out of engagement with said elevation adjustment guide in response to the operation of said lock actuator to permit said elevation adjustment member to slide through said elevation adjustment guide so that the elevation of said adjustable arm interconnected to said elevation adjustment member can be correspondingly changed; a lock housing carried by said elevation adjustment member and slidable therewith through said hollow elevation adjustment guide, said lock sliding through said lock housing from a locked position at which said lock is moved into engagement with said elevation adjustment guide to an unlocked position at which said lock is moved out of engagement with said elevation adjustment guide; an elongated actuator arm extending between said lock actuator and said lock by which to enable said lock to communicate with said lock actuator, the operation of said lock actuator causing said elongated actuator arm to move longitudinally through said elevation adjustment member to cause said lock to slide in said lock housing to said unlocked position; and a first spring surrounding said elongated actuator arm within said elevation adjustment member, said first spring being compressed and storing energy when said lock actuator is operated and said actuator arm moves longitudinally through said elevation adjustment member towards said lock housing, and said first spring expanding and releasing its stored energy to force said actuator arm to move away from said lock housing when said lock actuator is no longer operated.