Patent ID: 6746575
Filing Date: 2004-06-08
Classification: D21G

Abstract:
A doctoring device adapted for use with a paper machine suction roll having a suction roll axis of rotation, said doctoring device comprising:a doctor blade holder; a doctor blade fixed on said blade holder, said doctor blade having an edge against said suction roll and contacting said suction roll at an angle disposed relative to a tangent of said suction roll at the point of contact; a doctor slat holder; a doctor slat connected to said slat holder, said doctor slat having an edge in urged engagement with said suction roll through a foil effect and contacting said suction roll at an angle disposed relative to a tangent of said suction roll at the point of contact; said doctor slat contact angle being smaller than said doctor blade contact angle; an angle defined by a first radius extending from the suction roll axis of rotation to the point of contact with said doctor blade and a second radius extending from the suction roll axis of rotation to the point of contact with said doctor slat being in the range of 15 degrees to 70 degrees; said doctor blade being circumferentially disposed along said suction roll downstream of said doctor slat in a direction of rotation of said suction roll; and a frame spacedly mounting both said doctor blade and said doctor slat; said frame having a trough formed therein which collects water that has been drawn onto the surface of said suction roll by said doctor slat.