Machine for stabilizing a track

A machine for stabilizing a track, comprising:

• a machine frame:
• on-track undercarriages;
• a vertically adjustable stabilizing unit having unit rollers wherein the machine frame is supported on said on-track undercarriages and said vertically adjustable stabilizing unit designed to roll on rails of the track by means of said unit rollers;
• wherein the stabilizing unit comprises:
• a vibration exciter with rotating imbalance masses for generating an impact force (FS) acting dynamically in a track plane perpendicularly to a track longitudinal direction and
• a vertical drive for generating a vertical load acting on the track, wherein the vibration exciter comprises:
• at least two imbalance masses forming an imbalance pair comprising a left-turning imbalance mass and a right-turning imbalance mass and wherein at least one imbalance mass of said imbalance mass pair is driven applying a first phase shift (Δφ1) which is variably adjustable with respect to an initial position which are driven applying a variably adjustable phase shift (Δφ1, Δφ2);
• wherein the vibration exciter comprises at least four rotatable imbalance masses, of which two imbalance masses-in each case are driven right-turning and two imbalance masses are driven left-turning;
• and
• wherein the two left-turning imbalance masses are driven with a variably adjustable second phase shift (Δφ2) to one another, and wherein the two right-turning imbalance masses are driven with a variably adjustable second phase shift (Δφ2) to one another.