Pantograph carriage

This particular system for track changing is composed of two different articulated systems: a crank and slotted link and an articulated quadrilateral. The first delivers the movement, the second drives the boxes during movement. The undercarriage symmetry, the compactness of the system in case of same expanded track, the higher strength of the undercarriage and a larger widening capacity, starting with the same dimensions, are the advantages offered by this type of undercarriages. On the other hand, the pantograph system is far more complex. This fact makes the pantograph carriages suitable to applications requiring high stability and a wide support base. The undercarriages with this widening system are therefore used very often with cranes or lifting systems.