Variable-pitch fan with low pitch of a turbine engine

Patent metadata

Field	Value
Publication number	US-2017191495-A1
Application number	US-201715398133-A
Country	US
Kind code	A1
Filing date	Jan 4, 2017
Priority date	Jan 5, 2016
Publication date	Jul 6, 2017
Grant date	—

Abstract

A fan of a turbine engine, the fan including a fan disk provided with blades on its periphery, the blades being pivotally mounted on the disk around a pivoting axis and having a center of gravity, and a pitch change mechanism for the blades, each blade being configured so that its center of gravity is positioned on or at a small distance from a fictitious plane which passes through the pivoting axis of the blade and which is perpendicular to the axis of revolution of the fan when the blade is in a minimum drag position.

First claim

1 . A fan of a turbine engine, said fan comprising:
a disk of annular overall shape and defining an axis of revolution of the fan, said disk being provided with blades at its periphery, said blades being pivotally mounted on the disk around a pivoting axis and having a center of gravity, and a pitch change mechanism of said blades, said mechanism being configured to adjust an angular position of each blade around the pivoting axis, wherein each blade has a first portion, which extends in an airstream of the fan, and a second portion which extends outside said airstream, a center of gravity of the second portion of the blade extending substantially on the pivoting axis while a center of gravity of the first portion of the blade is offset with respect to said pivoting axis by being on or at a small distance from a fictitious plane which passes through the pivoting axis of said blade and which is perpendicular to the axis of revolution of the fan when the blade is in a minimum drag position.

2 . The fan according to claim 1 , wherein each blade is configured so that its center of gravity is located between two secant planes along a straight line corresponding to the pivoting axis and each forming an angle of ten degrees with the fictitious plane.

3 . The fan according to claim 1 , wherein each blade is configured so that its center of gravity is positioned in proximity to the pivoting axis.

4 . The fan according to claim 1 , comprising a hub ratio less than or equal to 0.35.

5 . The fan according to claim 1 , having an external diameter comprised between eighty inches (203.2 centimeters) and a hundred inches (254.0 centimeters).

6 . A turbine engine comprising a fan housed in a fan casing, said fan comprising:
a disk of annular overall shape and defining an axis of revolution of the fan, said disk being provided with blades at its periphery, said blades being pivotally mounted on the disk around a pivoting axis and having a center of gravity, and a pitch change mechanism of said blades, said mechanism being configured to adjust an angular position of each blade around the pivoting axis, wherein each blade has a first portion, which extends in an airstream of the fan and a second portion, which extends outside said airstream, a center of gravity of the second portion of the blade extending substantially on the pivoting axis while a center of gravity of the first portion of the blade is offset with respect to said pivoting axis by being on or at a small distance from a fictitious plane which passes through the pivoting axis of said blade and which is perpendicular to the axis of revolution of the fan when the blade is in a minimum drag position.

7 . The turbine engine according to claim 6 , further comprising a turbine in fluid communication with the fan and a reduction mechanism coupling the turbine and the fan, the reduction mechanism being of the star gear or planetary gear type and having a reduction ratio comprised between 2.5 and 5.

8 . The turbine engine according to claim 6 , having a bypass ratio greater than or equal to 10, preferably comprised between 12 and 18.

Assignees

• Safran Aircraft Engines

Inventors

• Bordoni Nils Edouard Romain
• Brault Michel Gilbert Roland
• Cuvillier Romain Guillaume
• Kubiak Guillaume Patrice
• Negri Arnaud Nicolas
• Nowakowski Nathalie

Classifications

• F04D29/366

  Adjustment by interaction of inertion and lift · CPC title

• F05D2260/40311

  of the epicyclical, planetary or differential type · CPC title

• F02K3/06

  with front fan · CPC title

• F05D2220/36

  specially adapted for the fan of turbofan engines · CPC title

• F04D29/36 Primary

  adjustable {(flexible blades F04D29/382)} · CPC title