Patent ID: 7946788

Claim:
A road construction machine for the treatment of road surfaces, comprising: a milling drum, the milling drum being height adjustable with regard to milling depth and/or slope; and a leveling system operable to control the milling depth and/or the slope of the milling drum, the leveling system including: a plurality of selectable sensors for sensing current actual values of operating parameters including the milling depth and/or the slope of the milling drum relative to a reference surface; a plurality of indication and setting devices, each of the indication and setting devices being associatable with at least one of the plurality of selectable sensors, each indication and setting device being operable to indicate the current actual value of and to set a set value for the operating parameter sensed by its associated sensor; a controller operable to control the milling depth and/or the slope of the milling drum conditioned on set values and sensed current actual values of the operating parameters sensed by a selected subset of the plurality of selectable sensors by returning at least one adjustment value to adjust the milling depth and/or slope of the milling drum so that the sensed current actual values of the operating parameters approach the set values for the selected subset of the plurality of selectable sensors; a switchover device operable to switch over from control based upon a first selected subset of the plurality of selectable sensors to control based upon a second selected subset, the second selected subset exchanging at least one replacement sensor not in the first subset for at least one replaced sensor that was in the first subset; and the controller being operable to effect switchover from control based upon the first selected subset of selectable sensors to control based upon the second selected subset of selectable sensors during milling operation without interruption of the milling operation and without any erratic alteration of the at least one adjustment value for adjusting the milling depth and/or slope of the milling drum.