US Patent 10350121 Electrically powered wheelchair with an armrest adjustment arrangement

An electrically powered wheelchair includes a chassis, seat frame, seat frame tilt and lift system, armrest assembly pivotally coupled to the seat frame, and armrest adjustment arrangement including: a first force transmitting arrangement having a first set of four pivot points and pivotally coupled to: an arm of the seat frame tilt and lift system via a first pivot point of the first set of four pivot points, and lifting member of the seat frame tilt and lift system via a second pivot point of the first set of four pivot points, and a second force transmitting arrangement having a second set of four pivot points and pivotally coupled to: the first force transmitting arrangement via a first pivot point of the second set of four pivot points, the seat frame via a second pivot point of the second set of four pivot points, and the armrest assembly.