Patent ID: 9273696
Filing Date: 2016-03-01
CPC Classification: F04D,F05D,Y10T

Claim Text:
1. An axial fan comprising: a circular-cylindrical blower pipe having an internal diameter, wherein the circular-cylindrical blower pipe is configured with a fan rotor, which fan rotor has a rotor shaft which coincides with a centre axis of the circular-cylindrical blower pipe, wherein the fan rotor comprises: wherein each blade has a proximal end secured to the rotor hub, and a distal end at an outer diameter of the rotor which is smaller than an internal diameter of the blower pipe, wherein the rotor hub comprises an outer shell having an outside hub surface which is rotational-symmetrical about the centre axis of the rotor hub; and wherein the rotor hub has a front end and a rear end and a diverging section there between extending from the front end to the rear end of the rotor hub, where a radius of the hub surface in the diverging section is increased by a distance to the front end on the rotor, wherein the rotor hub and the blades are made as separate metal parts; and wherein the rotor blades are securely mounted only to the diverging section on the hub surface, wherein the hub further comprises a shaft part extending within the outer shell along the centre axis of the rotor hub, which shaft part comprises means for mounting of the rotor hub on a dive shaft and being connected to the outer shell at the front end thereof, wherein, for each individual blade on the fan rotor, a first reinforcement rib is configured to extend between the shaft part and the outer shell and to support the outer shell underneath the blade relative to the shaft part, and wherein, for each blade, one or more further reinforcing ribs are configured to extend between the shaft part and the outer shell, to be arranged next to the first reinforcement rib, and to support areas on the outer shell to both sides of the area that is supported by the first reinforcing rib.