Patent ID: 9624903
Date: 2017-04-18
CPC Classifications: F03B,F03D,Y02E

Claim:
1. A drive apparatus for driving an electrical generator, the drive apparatus comprising: a shaft; a pair of first arms spaced apart along the shaft and rotatably and pivotably coupled to the shaft, wherein each first arm extends radially outwards from the shaft; a pair of second arms spaced apart along the shaft and rotatably and pivotably coupled to the shaft, wherein each second arm extends radially outwards from the shaft; a first blade extending between the first arms and spaced from the shaft, the first blade being supported by the first arms; a second blade extending between the second arms and spaced from the shaft, the second blade being supported by the second arms; and a flap pivotably mounted to the shaft and operatively engaged with the first arms and the second arms such that pivotal movement of the flap relative to the shaft pivots the first arms and the second arms relative to the shaft; wherein the drive apparatus is configured such that, when in use, each first blade and each second blade experiences fluid dynamic lift, and a direction of fluid flow causes the flap to align with the flowing fluid to cause pivotal movement of the first arms and the second arms relative to the shaft such that each first blade and each second blade follows an orbit which is inclined relative to the shaft, said orbit being inclined such that each said first blade and each said second blade cross the fluid flow at an upstream side of the drive apparatus at a first height, and cross the fluid flow at a downstream side of the drive apparatus at a second height, the second height being different from the first height.