Height adjustable chair arm assembly

An arm height adjustment mechanism for a chair, comprising:

• a support tube adapted to be fixed to a chair;
• an elongated lock member fixed within said support tube and defining a plurality of vertically spaced lock sockets;
• an elongated lock guide tube slideably mounted within said support tube;
• an armrest joined to said guide tube;
• a lock rod having a lower end, said rod being slideably disposed within said guide tube and movable from a locked position to an unlocked position;
• a lock element within said lock guide tube, said lock element being engaged by said lower end of said lock rod and being retained within one of said sockets when said rod is in the locked position and being released from one of the sockets when said rod is in the unlocked position permitting the lock guide tube to be moved vertically with respect to said support tube;
• a lock release housing joined to said lock guide tube, said armrest being secured to said lock release housing, a release lever joined to said lock rod and movable vertically within said lock release housing;
• and
• resilient means between said housing and said release lever for resiliently biasing said release lever and said lock rod to the locked position, said lock guide tube defining an aperture through which said lock element extends.

An arm height adjustment mechanism for a chair, comprising:

• a support tube adapted to be fixed to a chair;
• an elongated lock member fixed within said support tube and defining a plurality of vertically spaced lock sockets;
• an elongated lock guide tube slideably mounted within said support tube;
• an armrest joined to said guide tube;
• a lock rod having a lower end, said rod being slideably disposed within said guide tube and movable from a locked position to an unlocked position;
• a lock element within said lock guide tube, said lock element being engaged by said lower end of said lock rod and being retained within one of said sockets when said rod is in the locked position and being released from one of the sockets when said rod is in the unlocked position permitting the lock guide tube to be moved vertically with respect to said support tube;
• and
• an outer tube surrounding said lock guide tube and telescoping over said support tube.

An arm assembly for a chair, comprising:

• an arm support adapted to be secured to a chair;
• an inner tube joined to said arm support;
• an elongated lock plate disposed within said inner tube, said lock plate defining a plurality of vertically spaced lock indentations;
• a lock tube including an upper lock release housing and an elongated guide tube which defines a lock element aperture, said guide tube being telescopingly disposed within said inner tube;
• an elongated lock rod movably disposed within said lock tube;
• a lock element within said lock aperture, said element being engaged by said lock rod;
• a spring operatively connected to the rod and resiliently biasing the rod to a locked position wherein said lock element is retained within one of said indentations preventing vertical movement of the lock tube with respect to said inner tube;
• and
• an arm cap mounted on said lock release housing.