Fluid Turbine Having Improved Cam and Follower Mechanism

Abstract

A fluid turbine comprising a blade pitch control mechanism comprising a cam and at least one rocker assembly, each rocker assembly comprising a rocker arm operable to pivot about an axis of rotation, the blade pitch control mechanism being operable to control the pitch angle of at least one rotor blade about its pitch axis and to vary the pitch angle of the rotor blade from a first pitch angle at a first circumferential location about the axis of rotation to a second pitch angle at a second circumferential location about the axis of rotation.

1 . A fluid turbine comprising:
 a rotor, having an axis of rotation, comprising at least two rotor blades disposed at a radius from the axis of rotation, each rotor blade having a pitch axis and a variable pitch angle; and   a blade pitch control mechanism comprising a cam and at least one rocker assembly, each rocker assembly comprising a rocker arm operable to pivot about an axis of rotation, the blade pitch control mechanism being operable to control the pitch angle of at least one rotor blade about its pitch axis and to vary the pitch angle of the rotor blade from a first pitch angle at a first circumferential location about the axis of rotation to a second pitch angle at a second circumferential location about the axis of rotation.   
     
     
         2 . The fluid turbine of  claim 1 , wherein the rocker assembly comprises a rocker cartridge which acts as a frame for the rocker assembly. 
     
     
         3 . The fluid turbine of  claim 2 , wherein the rocker cartridge has a cylindrical body protruding from the back of a front flange, and a generally-cylindrical aperture passing from front to back. 
     
     
         4 . The fluid turbine of  claim 3 , wherein a rocker arm is mounted to a shaft passing through the cylindrical aperture in the body of the rocker cartridge, and mounted in such a manner as to pivot about an axis of rotation passing through the aperture. 
     
     
         5 . The fluid turbine of  claim 4 , wherein a cam follower bearing is secured to the distal end of the rocker arm and oriented in such manner as to freely rotate about an axis of rotation generally parallel to, but offset from, the axis of rotation of the rocker arm. 
     
     
         6 . The fluid turbine of  claim 1 , further comprising a lever arm secured to an actuation rod in such a manner as to move an actuation rod as the rocker arm rotates. 
     
     
         7 . The fluid turbine of  claim 6 , wherein the actuation rod is secured at a first end to the rocker arm and at a second end to a rotor blade. 
     
     
         8 . A fluid turbine comprising:
 a rotor, having an axis of rotation, comprising at least two rotor blades disposed at a radius from the axis of rotation, each rotor blade having a pitch axis and a variable pitch angle; and   a blade pitch control mechanism comprising a cam and at least one rocker assembly, each rocker assembly comprising a rocker arm operable to pivot about an axis of rotation and a cam follower bearing, secured to the distal end thereof, operable to ride on a surface of the cam, the blade pitch control mechanism being operable to control the pitch angle of at least one rotor blade about its pitch axis and to vary the pitch angle of the rotor blade from a first pitch angle at a first circumferential location about the axis of rotation to a second pitch angle at a second circumferential location about the axis of rotation.   
     
     
         9 . The fluid turbine of  claim 8 , wherein the rocker assembly comprises a rocker cartridge which acts as a frame for the rocker assembly. 
     
     
         10 . The fluid turbine of  claim 9 , wherein the rocker cartridge has a cylindrical body protruding from the back of a front flange, and a generally-cylindrical aperture passing from front to back. 
     
     
         11 . The fluid turbine of  claim 10 , wherein the rocker arm is mounted to a shaft passing through the cylindrical aperture in the body of the rocker cartridge, and mounted in such a manner as to pivot about an axis of rotation passing through the aperture. 
     
     
         12 . The fluid turbine of  claim 11 , wherein a cam follower bearing is secured to the distal end of the rocker arm and oriented in such manner as to freely rotate about an axis of rotation generally parallel to, but offset from, the axis of rotation of the rocker arm. 
     
     
         13 . The fluid turbine of  claim 8 , further comprising a lever arm secured to an actuation rod in such a manner as to move an actuation rod as the rocker arm rotates. 
     
     
         14 . The fluid turbine of  claim 13 , wherein the actuation rod is secured at a first end to the rocker arm and at a second end to a rotor blade. 
     
     
         15 . A fluid turbine comprising:
 a frame,   a rotor, comprising a hub secured to the frame in such manner as to rotate about an axis of rotation with respect thereto and at least two rotor blades disposed at a radius from the axis of rotation, each rotor blade having a pitch axis and a variable pitch angle; and   a blade pitch control mechanism comprising:
 a cam having a surface defining a rotor blade pitch profile and 
 at least one rocker assembly, each rocker assembly comprising a rocker arm secured to the hub in such manner as to pivot about an axis of rotation with respect thereto and a cam follower bearing, secured to the distal end thereof, operable to ride on the surface of the cam, 
 the blade pitch control mechanism being operable to control the pitch angle of at least one rotor blade about its pitch axis and to vary the pitch angle of the rotor blade from a first pitch angle at a first circumferential location about the axis of rotation to a second pitch angle at a second circumferential location about the axis of rotation. 
   
     
     
         16 . The fluid turbine of  claim 15 , wherein the rocker assembly comprises a rocker cartridge which acts as a frame for the rocker assembly. 
     
     
         17 . The fluid turbine of  claim 16 , wherein the rocker cartridge has a cylindrical body protruding from the back of a front flange, and a generally-cylindrical aperture passing from front to back. 
     
     
         18 . The fluid turbine of  claim 17 , wherein a rocker arm is mounted to a shaft passing through the cylindrical aperture in the body of the rocker cartridge, and mounted in such a manner as to pivot about an axis of rotation passing through the aperture. 
     
     
         19 . The fluid turbine of  claim 15 , wherein a cam follower bearing is secured to the distal end of the rocker arm and oriented in such manner as to freely rotate about an axis of rotation generally parallel to, but offset from, the axis of rotation of the rocker arm. 
     
     
         20 . The fluid turbine of  claim 16 , further comprising a lever arm secured to an actuation rod in such a manner as to move an actuation rod as the rocker arm rotates.