Patent ID: 8902031

Claim:
A guide device having passive gravity compensation by a magnet assembly for guiding a first body relative to a second body in a vertical direction, comprising: a spring guide adapted to allow movement between the first body and the second body in the vertical direction and blocking movement between the first body and the second body in other directions; a first magnet connectable to the first body; a second magnet connectable to the second body; and a ferromagnetic cylinder; wherein the first magnet and the second magnet are magnetized parallel to the vertical direction and magnetized oppositely to each other; wherein the second magnet includes an opening and the first magnet is at least in part arranged in the opening so that a repulsion force, which counteracts gravity on the first body, acts between the first magnet and the second magnet; wherein a positive stiffness of the spring guide is at least partially compensated by a negative stiffness of a magnetic spring formed by the first magnet and the second magnet; wherein the first magnet and the second magnet are shaped such that a horizontal distance between the first magnet and the second magnet inside of the opening of the second magnet varies in the vertical direction; wherein the second magnet is provided on a ferromagnetic plate; and wherein the ferromagnetic cylinder surrounds the magnet assembly and is provided on the ferromagnetic plate.