Roll for treatment of paper webs or the like

Claim 1

A roll for pressure treatment of webs, especially paper webs, comprising an elongated shaft; a hollow cylindrical sleeve having a longitudinal axis, a transverse axis normal to said longitudinal axis, and a concave cylindrical internal surface spacedly surrounding said shaft; and at least one bearing shoe interposed between said shaft and said sleeve, said shoe being movable substantially radially of and tiltable relative to said shaft and defining with said shaft a plenum chamber for a supply of pressurized hydraulic fluid which urges said shoe in a direction toward said internal surface, said shoe having a convex cylindrical external surface adjacent to said internal surface and including a substantially centrally located primary hydrostatic bearing pocket communicating with said plenum chamber and at least four isolated auxiliary hydrostatic bearing spockets spaced so as to effectively surround said primary pocket, said external surface further including a marginal portion surrounding said pockets and lands separating said primary pocket from said auxiliary pockets, said primary pocket having arms extending to said marginal portion, flanked by said auxiliary pockets and substantially parallel with at least one of said axes, said primary pocket further having a central portion and said shoe having a single channel connecting said plenum chamber with the central portion of said primary pocket, said auxiliary pockets being isolated from the primary pocket without direct hydraulic fluid communication therebetween and being placed so as to receive fluid which leaks from said primary pocket and overflows along the respective lands between the primary pockets and the auxiliary pockets.