| 摘要 |
An apparatus comprising: a frame; a shaft mounted to the frame for rotation; plural vanes each mounted for rotation about a respective pitch adjustment axis on one or more respective arms extending from the shaft; a collar mounted to the frame coaxial with the shaft, the collar having a first outer circumferential surface defining a convex cam shape, and a second outer circumferential surface defining a non cam circular shape; and plural followers arranged to contact the first outer circumferential surface in a first configuration corresponding to a first speed of rotation of the shaft and the second outer circumferential surface in a second configuration corresponding to a second speed of rotation of the shaft, the second speed being higher than the first speed, the plural followers being each connected to adjust the pitch of a respective vane of the plural vanes. |
