Patent ID: 8919737

Claim:
A traction device for paying out and retrieving a flexible line, said traction device comprising a line mover wherein: the line mover comprises at least one movable friction surface; the at least one friction surface in total defines at least two arc sections configured to move the line along with said arc sections; in use the line is wound around said at least one friction surface such that the line comprises a first contact area being in contact with the first arc section and a second contact area being in contact with the second arc section; and the traction device comprises a line controller coupled to the line between the first contact area and the second contact area as seen along that part of the line between the first contact area and the second contact area, and configured to control a velocity (v 3 ) with which the line in use is fed to the second arc section, wherein the velocity (v 3 ) with which the line is fed to the second arc section is adjusted to a second arc section velocity with which said second arc section moves for compensating a first arc section strain of the line occurring during a passing of the first arc section, the line controller being configured to adjust the length of the part of the line extending between the first contact area and the second contact area.