US Patent 7543888 Vehicle seats

A vehicle seat can include a seat back and a head rest. The seat back includes an upper half corresponding to a shoulder portion of a passenger, a lower half corresponding to a waist portion of the passenger, and an head rest height adjustment mechanism. The seat back upper half is connected to a structural component of the head rest or a movable component of the head rest height adjustment mechanism, so as to be vertically moved relative to the seat back lower half when the head rest height adjustment mechanism is actuated.