Position adjustable armrest assemblies for passenger seats

An armrest assembly for an aircraft passenger seat, comprising:

• a height-adjustable base coupled for vertical movement along a stationary rail;
• a first arm having a first end pivotally attached to the height-adjustable base;
• a second arm having a first end pivotally attached to the height-adjustable base;
• an arm support element pivotally connected to a second end of the first arm and pivotally connected to a second end of the second arm;
• and
• a stationary assist device coupled to the height-adjustable base and at least one of the first and second arms operable for applying force to at least one of the first and second arms to bias the arm support element from a first position toward a second position higher than the first position.

An armrest assembly for an aircraft passenger seat, comprising:

• a stationary base attachable to a structure;
• a first arm having a first end pivotally attached to the base;
• a second arm having a first end pivotally attached to the base;
• an arm support element;
• and
• a coupling member by which the arm support element is pivotally coupled to a second end of the first arm and a second end of the second arm, the coupling member comprising a first vertical planar element pivotally connected to at least one of the second end of the first arm and the second end of the second arm;
• wherein the base, the coupling member, the first arm, and the second arm operate together as a four-bar linkage system, and wherein the base is height-adjustable along a stationary rail.