Perfected air pad

An air pad for supporting a first member in relation to a second member, said members being mutually slidable, said pad comprising a body having two opposite faces, said body being provided with a number of supporting orifices located on one of said faces and supplied with compressed air, at least one compensating orifice being associated with the other of said faces and being supplied with compressed air, said body being removably connected to said first member, said second member comprising two contrast surfaces facing said two faces, wherein the improvement comprises a micropad provided with said compensating orifice and movable in relation of said body in a direction parallel to the axis of said compensating orifice, each one of said contrast surfaces constantly covering the orifices of the relevant facing face, said micropad being urged by compressed air toward the contrast surface facing said other face, said micropad having an active surface so sized as to cause said compensating orifice to generate a preload to compensate any variation on the load on said pad occurring during the mutual sliding of said members.