Air flotation turner bar

A turner device for providing support for a travelling web within a zone along its path where it undergoes an arcuately curved directional change, said device comprising means defining an air plenum including two opposed spaced apart generally solid side walls extending perpendicularly to the plane of the web in adjacent spaced relation to the extreme web edges, opposed arcuately curved flanges each formed integrally with one such side wall and projecting inwardly therefrom for underlying limited overlapping relation with the corresponding marginal strips of the web passing between the planes of said side walls, said flanges being coaxially arranged with their curvature corresponding to the curvature of the web directional change, the mutually facing edges of said flanges being spaced apart a distance equal to the transverse width of said web less said marginal strips and the intervening space being substantially open and unobstructed to leave the web substantially unsupported in said intervening space, means for supplying air to said plenum under pressure sufficient to provide during travel of the web an air cushion below the curved web portion to support the web while undergoing said directional change, and web constraining means within said plenum for preventing the web from being accidentally drawn as far as the center of curvature of said curved flanges.