Patent attributes
A powered steering mechanism can operate in a steering mode or in a powered self-centering mode. The mechanism of the present invention includes a cylinder into and out of which can reciprocate a rod. The rod is provided with a fixed piston that defines a first pressure chamber and a second pressure chamber. First and second inlet/outlet steering ports are provided in the pressure chambers through which a pressurizing fluid can flow into or out. The cylinder is also adapted to provide powered self-centering of the fixed piston and thereby the steering mechanism itself by the floating pistons that are located within the pressure chambers. First and second inlet/outlet centering ports are also provided in pressure chambers, through which fluid can flow into the chambers, causing floating pistons to move towards a central position and enabling the fixed piston to be moved and retained.