Assembly for supporting and guiding a movable member of a machine, particularly a measuring machine

An assembly (10) for supporting and guiding a movable member (3) of a machine (1) for movement along an axis (X) relative to a support member of the machine (1) itself, of the type comprising a first slide surface (14) formed on the support member (2) and extending parallel to the said axis X, at least a first bearing pad fixed to the movable member (3) and slidable on the first surface (14), a second slide surface (15) formed on the support member (2) and extending parallel to the said axis (X), at least one second bearing pad (19) fixed to the movable member (3) and slidable on the second surface (15), the first and second surfaces (14, 15) extending in respective planes which intersect each other, characterized in that it includes a third slide surface (16) formed on the support member and extending in a direction parallel to the said axis (X) and in a plane inclined to the said planes in which the first and second slide surfaces (14, 15) lie, and at least one third bearing pad (20) fixed to the movable member (3), slidable on the third surface (16) and arranged to balance the loads exerted by the first and second bearing pads (18, 19) on the first and second slide surfaces (14, 15) and further characterized in that the third bearing pad is magnetic, the third surface lying in a plane forming respective obtuse internal dihedral angles with the planes in which the first and second surfaces lie.