US Patent 8060985 Hinge structure with changeable frictional faces

The present invention discloses a hinge structure with changeable frictional faces, comprising a spindle socketingly disposed with a first enclosing part and a second enclosing part with the openings of the first and second enclosing parts pointing to the same direction to change the frictional face for torsion from the second enclosing face to the first enclosing part and thus to extend the service life and further to form a frictional face with four steps of different torsions to meet the demands of customers.