Patent ID: 7690407

Claim:
A method in a sawing apparatus of a forest machine for preventing the whipping movement of a saw chain breaking during sawing, wherein the method comprises the steps of: driving the saw chain around a guide bar by using a drive gear positioned on one end of the guide bar, wherein the saw chain moves from the guide bar at the drive gear and rotates back on top of the drive gear, and wherein the guide bar is connected to a guide bar holder, conducting the sawing of a tree trunk by rotating the guide bar holder around a first rotation axis with respect to a frame part for turning the guide bar during the sawing, wherein the frame part is configured for supporting the sawing apparatus, and moving a protective wall during the sawing of a tree trunk in phase with the rotation of the guide bar to maintain the mutual position of the protective wall and the guide bar, wherein the protective wall is connected to the guide bar holder and positioned in such a manner that the protective wall is capable of receiving the saw chain breaking during the sawing as well as the tail of the broken saw chain, which tend to continue moving past the drive gear, and guiding the saw chain and the tail to a desired direction.