Patent attributes
A plurality of sliding rails and a frame structure comprising a plurality of frame elements configured to be arranged at least partly circumferentially around a tower structure. Each frame element is slidably connected to at least one of the sliding rails, and the frame elements and the sliding rails are interconnected to form a scissor structure. An upwardly directed lifting force applied by a hoisting mechanism at connecting points at or near positions where the frame elements are connected to the sliding rails, in combination with gravity working on the frame structure, causes the frame elements to slide along the sliding rails, thereby causing the scissor structure to contract or expand to adjust a diameter of the frame structure to an outer diameter of the tower structure having the apparatus mounted thereon.