Device for sliding support

A supporting device to slidingly support, and linearly move along an axis an object, comprising:

• an empty channel extending parallel to the axis,
• a magnetic flux generator for creating a magnetic flux that crosses a segment of the empty channel with magnetic field lines which are all equally-oriented,
• a first element, reactive to the magnetic field, which is arranged in the empty channel and which extends along said axis,
• the first element being configured to slide relative to the channel parallel to the axis during the movement of the object,
• wherein the first element in correspondence of said channel segment has a cross-section which, seen in a plane orthogonal to the axis, has a dimension along the width of the channel,
• the first element having a length considered along said axis,
• wherein said dimension has a value that varies along the length of the first element parallel to said axis so that where said dimension reduces or increases there develops a force tending to move the first element relatively along the axis with respect to the channel in order to bring the first element and the channel back in a certain relative position.