Dog Gear?

[Dan-o]

We are designing a similar system since we don't have room in our budget for 1 or 2 Super-Shifters. Unfortunately, I am having trouble understanding just one concept about this method of power transmission.

My understanding is that the power source (crankshaft) is connected to the output rod (driveshaft) by a pair of gears. The input gear is rigidly coupled to the crankshaft. The output gear is connected by a bearing to the driveshaft so it can rotate freely if the dog collar is not engaged. The dog collar is coupled to the driveshaft so that it rotates with the shaft, but can move axially to engage or disengage the output gear.

First, is my understanding of this system correct? Second, how can a piston push or pull the dog collar as it rotates on the shaft? In other words, I need to undestand the linkage from the piston to the dog collar.

Thank you very much in advance for any help you can provide.