11/07/1978
Patent Awarded for Cam-Operated Pitch-Change Apparatus
Topic: Patent View this topic by decade -->

Patent number: 4,124,330

LEW number: 13,050-1

Date issued: November 7, 1978

Assignee: NASA

Inventor: Phillip E. Barnes

Abstract: A pitch-change apparatus for a ducted thrust fan having a plurality of variable pitch blades employs a camming ring mounted coaxially of the hub at an axially fixed station along the bug axis for rotation about the hub axis both with the blades and relative to the blades. The ring has a generally spherical outer periphery and a plurality of helical camming grooves extend in a generally spherical plane on the periphery. Each of the variable pitch blades is connected to a pitch-change horn having a cam follower mounted on its outer end, and the camming ring and the horns are so arranged about the hub axis that the plurality of followers on the horns engage respectively the plurality of helical camming grooves. Rotary drive means receives pitch-change commands from an appropriate controller and rotates the camming ring relative to the blades to cause blade pitch to be changed through the cooperative operation of the camming grooves on the ring and the cam followers on the pitch-change horns.

*Selecting the links below will take you off of this site. To return please use your browser back button.

Web References: