| 摘要 |
<p>A track leveling, lining and tamping machine comprises a track lifting assembly, a leveling reference system associated with the track lifting assembly, the reference system including a reference line associated with each track rail, each reference line having a forward end and a rear end, a forward track sensing element supporting the forward end of the reference lines in an uncorrected track section, a rear track sensing element supporting the rear end of the reference lines in a corrected track section, and a level sensor associated with each track rail and supported on a corrected track section rearwardly of the track lifting assembly for measuring the level of each track rail with respect to the associated reference line, the level sensor generating a control signal responsive to the measured level, an element for measuring the cross level mounted on the rear track sensing element, the cross level measuring element generating a correction signal indicating any residual error in the desired cross level, a leveling control receiving the correction signal and the control signal, the control actuating the lifting drives of the track lifting assembly in response to the signals, and an adjustable device at the forward track sensing element for vertically adjusting the forward ends of the reference lines in response to a difference between the actual and desired cross level.</p> |
