Patent ID: 8091858

Claim:
A shut-off system for large conduit cross-sections, comprising: a swing flap which can be swung to and fro between two end positions about a pivot axis by a drive device which moves the swing flap between the two end positions, the drive device having a drive shaft which is connected to the swing flap via an elbow lever system, at least one lever arm rigidly connected to the drive shaft which is in operative connection with at least one operating cylinder for rotation of the drive shaft, a motion link which is fastened so as to be rotatable about a pivot bearing, wherein the at least one operating cylinder comprises a first operating cylinder, the first operating cylinder connected to the motion link to pivot the motion link about the pivot bearing, a transmission element provided between the lever arm and the motion link in order to transmit the pivoting motion of the motion link to the drive shaft, and the pivot bearing being longitudinally displaced toward and away from the drive shaft.