Machine and method for stabilizing a track

A machine for stabilizing a track, with a machine frame supported on rail-based running gears and at least one height-adjustable stabilizing unit which can be rolled on rails of the track via work unit rollers, comprising:

• a vibration exciter for generating an impact force acting dynamically in a track plane normal to a longitudinal direction of the track, and
• a linear drive for generating a load acting on the track, said linear drive comprising:
• at least one rotation shaft;
• a main unbalanced mass coupled to said at least one rotation shaft;
• and
• a secondary unbalanced mass rotatably coupled to said at least one rotation shaft and rotatable within a pre-defined angular range and configured to produce different centrifugal forces depending on the direction of rotation, wherein said main unbalanced mass and said secondary unbalanced mass form two unbalanced masses being coupled together wherein, during rotation in one direction of rotation, said main unbalanced mass and said secondary unbalanced mass are positioned on said at least one rotation shaft at a first position to have a first phase shift with respect to one another, and that, when rotating in the opposite direction of rotation, said main unbalanced mass and said secondary unbalanced mass are positioned at a second position on said at least one rotation shaft to have a second phase shift with respect to each other which differs from the first phase shift;
• and
• a plurality of constructive elements comprising catches, said plurality of constructive elements coupled to at least one of said main unbalanced mass and said secondary unbalanced mass and configured to limit a rotation of said secondary unbalanced mass relative to said main unbalanced mass on said at least one rotation shaft;
• wherein said main unbalanced mass and said secondary unbalanced mass comprise a pair of unbalanced masses and depending on the direction of rotation of each of said main unbalanced mass and said secondary unbalanced mass, one of two predetermined phase shifts results therefrom.