A vehicle seat for use with a vehicle. The vehicle seat includes a
seatback having a frame, a head restraint arrangement, an impact target
arrangement, and a ratchet screw mechanism. The impact target arrangement
is attached to the head restraint arrangement and moveably attached to
the frame. The ratchet screw mechanism includes a first threaded member
and a second threaded member. Upon application of a rearward force on the
impact target arrangement, the first threaded member at least partially
disengages the second threaded member to allow the head restraint
arrangement to move from an initial position to a support position.