Blade adjustment device axial fan - has servo cylinder mounted in impeller hub with series of elements attached to fan blade base mountings

摘要

An axial fan device having hydraulically or pneumatically steplessly variable impeller blades which can be moved during the fan rotation by means of a setting servo cylinder mounted in the impeller hub, and a piston such that the adjustment cylinder and the piston relate at the same speed as the drive shaft of the fan, has elements (ropes, chassis (22)) connected directly to one end of the coaxially adjustable piston (19) which run to the individual impeller blades and make contact with a larger radius than that on which the inner impeller blade cap mountings (6) are situated. These elements (22) are used to rotate the impeller blades whilst the impeller itself is running.