Blade pitch control arrangement

A water turbine assembly for installation in a water flow defining a flow direction, the assembly comprising:

• an array of blades that is rotatable by the water flow about a turbine axis, transverse to the flow direction, to describe a blade path surrounding the turbine axis, each of the blades being pivotable about a respective pitch axis, the pitch axes being distributed with mutual angular spacing along the blade path;
• and
• a cam formation positioned to be engaged with the blades while the blades traverse a first portion of the blade path and to be disengaged from the blades while the blades traverse a second portion of the blade path, wherein the blades are configured to pivot freely from a first stop position to a second stop position opposite the first stop position in response to a force of the water;
• wherein as each blade traverses the first portion of the blade path, pivoting of the blade about its pitch axis is controlled by engagement with the cam formation;
• and as each blade traverses the second portion of the blade path, the blade is pivotable about its pitch axis within a range of movement delimited by a respective pair of stop formations, the stop formations of each pair being angularly spaced in mutual opposition about the pitch axis of the associated blade.