I had a look at the Kitchen rudder patent and it appears what was claimed is a device that allows for forward, neutral and reverse all without disconnecting the prop from the motor. The way the 2 devices are used is not the same at all.
The motion of the kitchen rudder halves is symmetrical and some of the drawings show a common rotation axis for both parts of the rudder. The gate rudder uses 2 shafts and unequal rotation angles on each side and does not attempt to accomplish reverse or neutral drive positions at all. For steering the left and right parts rotate in opposite directions for course corrections, this could be similar to the kitchen rudder. For large deflections, the angular deflection of the 2 halves is asymetric. The "creep mode" rotates both halves of the rudder to one side of the Prop axis to provide more sideways thrust vectoring.
Presumably the rudder control mechanism is a bit more complex. Most likely a dual ram hydraulic system with encoders on both rudder shafts and a small plc which converts an incoming rudder angle command into a set of 2 shaft positions for each direction along with the additional "emergency stop" brake position.
For emergency operation for steering and losing some of the fancy functions, one could probably make a mechanical linkage between the pair of rudder quadrants and drive it with a regular hydraulic helm.
It will be interesting to see where this goes.
The motion of the kitchen rudder halves is symmetrical and some of the drawings show a common rotation axis for both parts of the rudder. The gate rudder uses 2 shafts and unequal rotation angles on each side and does not attempt to accomplish reverse or neutral drive positions at all. For steering the left and right parts rotate in opposite directions for course corrections, this could be similar to the kitchen rudder. For large deflections, the angular deflection of the 2 halves is asymetric. The "creep mode" rotates both halves of the rudder to one side of the Prop axis to provide more sideways thrust vectoring.
Presumably the rudder control mechanism is a bit more complex. Most likely a dual ram hydraulic system with encoders on both rudder shafts and a small plc which converts an incoming rudder angle command into a set of 2 shaft positions for each direction along with the additional "emergency stop" brake position.
For emergency operation for steering and losing some of the fancy functions, one could probably make a mechanical linkage between the pair of rudder quadrants and drive it with a regular hydraulic helm.
It will be interesting to see where this goes.
There have been twin rudder arrangements in use long before this setup, I actually wonder what the patent is covering. In fact, functionally the "Gate rudder" is just a slightly refined variant of the old "Kitchener rudder". One of the properties of this is the ability to influence the propeller flow at different propeller loadings; it acts as a "variable nozzle".