Machine and method for rehabilitating a track

A method for restoring a position of a track immediately after said position has been destroyed by the action of working units arranged on a machine frame of a machine mobile on the track on undercarriages, the machine frame comprising, with respect to an operating direction, a leading and a trailing frame part joined by an articulation, the working units being mounted on the trailing frame part, the method comprising the steps of:

• (a) detecting an actual track position by continuously measuring versines and/or an inclination of the track with respect to the longitudinal direction thereof in the region of the leading frame part, thereby establishing measuring values defining the lateral and/or vertical track position;
• (b) computing on the basis of said measuring values a locus corresponding to the actual track position and tied to a distance-based coordinate system;
• (c) matching the machine frame by calculation to the locus in three points, namely at the articulation and at the two undercarriages adjoining the same, thereby finding the theoretical target position of the trailing frame part with respect to the locus;
• (d) computing a target frame angle enclosed by the theoretical target position of the trailing frame part and the leading frame part;
• (e) computing the actual position of the trailing frame part with respect to the locus, based on the actual frame angle;
• (f) determining a control value for the working unit by forming the difference between the theoretical and actual position of the trailing frame part;
• and
• (g) actuating a drive for displacing the working unit relative to the trailing frame part in accordance with the said control values
• arranging a reference system being the leading frame part, wherein the reference system comprises
• a reference line extending in the longitudinal direction on the leading frame part,
• a measuring axle attached to the leading frame part and constructed to roll on the track,
• a measuring device connected to the measuring axle for detecting a movement, transversely to the longitudinal direction, of the measuring axle relative to the reference line, and
• an angle-measuring device formed by a cable potentiometer, arranged in the region of the articulation and connected to the leading and the trailing frame part, for detecting an actual frame angle enclosed by the leading and the trailing frame part;
• detecting an actual frame angle enclosed by the leading and the trailing frame part with the cable potentiometer;
• controlling the position of the working unit with the reference system.

A mobile machine for rehabilitating a track extending in a longitudinal direction, comprising

• (a) a machine frame extending in the longitudinal direction and supported by at least three undercarriages for mobility on the track in an operating direction, the machine frame being composed of
• (1) a leading frame part with respect to the operating direction and
• (2) a trailing frame part connected to the leading frame part by an articulation,
• (b) at least one working unit mounted on the machine frame for adjustment relative thereto,
• (c) a reference system for controlling the position of the working unit, the reference system being arranged on the leading frame part and consisting of
• (1) a steel chord furnishing a reference line extending in the longitudinal direction on the leading frame part,
• (2) a measuring axle designed to roll on the track and disposed on the leading frame part, and
• (3) a measuring device connected to the measuring axle for detecting a movement, transversely to the longitudinal direction, of the measuring axle relative to the steel chord, and
• (d) an angle-measuring device for detecting an actual frame angle enclosed by the leading and the trailing frame part, wherein the angle measuring device is formed by a cable potentiometer, arranged in the region of the articulation and connected to the leading and the trailing frame part, for detecting the actual frame angle enclosed with reference to a horizontal plane.