Self-propelled construction machine

A self-propelled construction machine, comprising:

• a machine frame;
• a milling drum arranged on the machine frame;
• a left-hand side-plate arranged on a left-side of the milling drum in a working direction;
• a right-hand side-plate arranged on a right-side of the milling drum in the working direction;
• a first double-acting hydraulic cylinder connected to the left-hand side-plate and configured to raise and lower the left-hand side-plate, the first double-acting hydraulic cylinder including two cylinder chambers;
• a second double-acting hydraulic cylinder connected to the right-hand side-plate and configured to raise and lower the right-hand side-plate, the second double-acting hydraulic cylinder including two cylinder chambers;
• a hydraulic system configured to raise and lower the left-hand and right-hand side-plates, the hydraulic system including:
• a hydraulic source for providing hydraulic fluid;
• a first auxiliary directional control valve operably associated with the first double-acting hydraulic cylinder and having two switch positions;
• a second auxiliary directional control valve operably associated with the second double-acting hydraulic cylinder and having two switch positions;
• one and only one main directional control valve operably associated with the first and second double-acting hydraulic cylinders and having three switch positions;
• wherein in a first switch position of the main directional control valve and in one of the two switch positions of the first and second auxiliary directional control valves, the hydraulic system is configured to provide hydraulic fluid to one of the two cylinder chambers of either or both of the first and second double-acting hydraulic cylinders such that either or both of the left-hand and right-hand side-plates can be raised;
• wherein in a second switch position of the main directional control valve and in one of the two switch positions of the first and second auxiliary directional control valves, the hydraulic system is configured to provide hydraulic fluid to the other of the two cylinder chambers of either or both of the first and second double-acting hydraulic cylinders such that either or both of the left-hand and right-hand side-plates can be lowered;
• wherein in a third switch position of the main directional control valve and in one of the two switch positions of the first and second auxiliary directional control valves, the hydraulic system is configured to provide a fluid connection between the two cylinder chambers of the first double-acting hydraulic cylinder and a fluid connection between the two cylinder chambers of the second double-acting hydraulic cylinder such that the left-hand and right-hand side-plates are floatingly mounted.