US 12,110,903 B2
Variable pitch fan of a gas turbine engine
Paolo Altamura, Monopoli (IT); and Giulio Zagato, Moncalieri (IT)
Assigned to GE Avio S.r.l., Rivalta di Torino (IT)
Filed by GE Avio S.r.l., Rivalta di Torino (IT)
Filed on May 12, 2023, as Appl. No. 18/316,656.
Claims priority of application No. 102022000022992 (IT), filed on Nov. 8, 2022.
Prior Publication US 2024/0151240 A1, May 9, 2024
Int. Cl. F04D 29/32 (2006.01); B64C 11/06 (2006.01); B64C 11/32 (2006.01); B64C 11/36 (2006.01); B64C 11/38 (2006.01); B64C 11/42 (2006.01); F02K 3/06 (2006.01)
CPC F04D 29/323 (2013.01) [B64C 11/32 (2013.01); F05D 2220/32 (2013.01); F05D 2260/74 (2013.01); F05D 2260/79 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A gas turbine engine, comprising:
a turbomachine comprising a compressor section, a combustion section, and a turbine section arranged in serial flow order;
a fan defining a fan axis and comprising a plurality of fan blades rotatable about the fan axis; and
a pitch change mechanism operable with the plurality of fan blades to control a pitch of the plurality of fan blades, the pitch change mechanism imparting a torque to each fan blade of the plurality of fan blades via first and second forces imparted in opposite directions to each fan blade of the plurality of fan blades;
wherein the pitch change mechanism comprises a forward unison ring and an aft unison ring;
wherein the pitch change mechanism further comprises a plurality of forward racks coupled to the forward unison ring and a plurality of aft racks coupled to the aft unison ring.