ALEXANDRIA, Va., Dec. 2 -- United States Patent no. 12,486,857, issued on Dec. 2, was assigned to ZIEHL-ABEGG SE (Kunzelsau, Germany).
"Fan having a step diffuser" was invented by Frieder Loercher (Braunsbach, Germany) and Andreas Gross (Kirchensall, Germany).
According to the abstract* released by the U.S. Patent & Trademark Office: "A fan, in particular an axial or diagonal fan, comprising a housing and an impeller arranged therein and driven by an electric motor and having vanes extending between a hub ring and a cover ring, wherein a step diffuser is formed in the form of an abrupt expansion of the flow cross-section in the direction of flow downstream of the impeller and after exiting the region of the cover ring."
The patent was fi...