Device for shifting between fine and coarse steering of vehicles comprising a front and a rear vehicle part

A device for shifting between fine and coarse steering operations for vehicles comprising front and rear vehicle parts articulately joined with each other, hydraulic steering cylinders disposed between said two vehicle parts for angularly displacing the vehicle parts relative to each other for accomplishing the steering of the vehicle, a first valve being adapted to control the fluid flow to the steering cylinders in order to provide for the fine steering of the vehicle, and a second valve being adapted to control the fluid flow to the steering cylinders to provide for the coarse steering, the improvement comprising:

• a shifting means, which is shiftable between two positions and is adapted in a first position to connect an actuator, provided for the steering of the vehicle, to the first valve, and a second position to connect the actuator to the second valve,
• said shifting means and said valves being arranged so that with the shifting means in the first position, a mutual angular displacement of the vehicle parts is obtained which is proportional to the movement of the actuator, and with the shifting means in the second position, a continuous angular diaplacement of the vehicle parts is obtained as long as the actuator is moved from a predetermined initial position.