Patent ID: 9168671
Filing Date: 2015-10-27
Classification: B27B,Y10T

Abstract:
1. A method for a sawchain for a forestry harvester in order to limit rapid outward movement of a free end of the sawchain relative to a guide bar if the sawchain breaks during sawing, the guide bar having a principal plane in which the sawchain travels during normal operation, the method comprises the steps: providing a sawchain with a means of limiting pivoting that protrudes from and in a direction orthogonal to a plane of a face of a driving link in the sawchain, the plane of the face of the driving link parallel to the principal plane of the guide bar, wherein the means of limiting pivoting allows a forwardly located link of the sawchain to pivot in an inward direction relative to a subsequent link while limiting the ability of the forwardly located link to pivot in an outward direction relative to the subsequent link, wherein the means of limiting pivoting is located completely above, in the outward direction, a central line through pivoting axes of the forwardly located link and the subsequent link, wherein the means of limiting pivoting is arranged at a region between pivot points of the forwardly located link and the subsequent link, wherein the means of limiting pivoting limits pivoting solely through interaction with opposite side edge parts of the forwardly located link and the subsequent link, with the opposite side edge parts of the forwardly located link and the subsequent link generally planar and facing one another, and wherein the means of limiting pivoting comprises a member that protrudes in the direction orthogonal, protruding away from the principal plane, the member having a round external surface that abuts against the generally planar side edge parts of the forwardly located link and the subsequent link, and wherein the protruding member forms a stop for the opposite side edge parts of the forwardly located link and the subsequent link, to prevent pivoting when in contact with the opposite side edge parts; driving the sawchain around the guide bar with a driving wheel that is located at one end of the guide bar, and sawing a tree trunk by turning the guide bar around an axis of rotation.