Patent ID: 8961109
Filing Date: 2015-02-24
Classification: F04D

Abstract:
1. A fan, comprising: a frame; a rotor supported rotatably by the frame and having a drive mechanism for rotatably driving the blades with the hub around the axis of the hub; a ring to which end zones of the blades are connected; wherein the ring is assembled from two part-rings of a same form which each include a strip of sheet material with a form of a part of a circular arc, free ends of which are mutually connected such that each strip has a form of an outer surface of a truncated cone, which thus strips are mutually connected with an outer circular peripheral edge of the strips; and the end zones of the blades are connected to the third part-ring; the ring has a diameter of more than about 1.50 m; a number of blades amounts to at least eight; and the blades are hollow and comprise a framework structure which is provided with a skin connected thereto.