Principle of operation
Neutral position (rectilinear motion)
The working fluid from the pump flows to the distribution valve. If the control valve is in the neutral position, then all the incoming working fluid will pass through the control valve to the discharge port to drain back to the pump. In this case, there is practically no pressure created, and since the pressure on the piston is equal on both sides of it, the piston will not move.
1 - steering arm shaft, 2 - screw, 3 - cylinder piston, 4 - power hydraulic cylinder, 5 - unloading hole, 6 - distribution valve.
On the bend
When turning the main steering shaft in any direction, the control valve also moves, blocking one of the channels for the working fluid.
In this case, another channel opens, providing a change in the volume of the flow of the working fluid, and at the same time pressure is created. Therefore, there is a pressure difference acting on both sides of the piston, which moves in the direction of reduced pressure, and the liquid on the other side of the cylinder is forced back to the pump through the control valve.