Patent ID: 7025303

Claim:
A turning bar for contactless guidance of a tubular film web ( 5 ) moved at a loop angle around the turning bar ( 1 ), the turning bar comprising: a support tube ( 10 ) having a hollow interior ( 14 ) connectible with a compressed air source, the support tube ( 10 ) having a plurality of air outlet openings ( 100 ) communicating with the interior ( 14 ) and spaced apart from each other substantially over an entire width of the support tube ( 10 ) within an angular area of the support tube ( 10 ) corresponding to the loop angle of the tubular film web ( 5 ); an air-permeable microporous layer ( 15 ) applied to the exterior of the support tube ( 10 ) and forming a surface (F) of the support tube ( 10 ) through which the compressed air exiting the air outlet openings ( 100 ) of the support tube ( 10 ) flows, the compressed air exiting the microporous layer ( 15 ) as a laminar air flow forming a laminar air cushion between the turning bar ( 1 ) and the tubular film web ( 15 ); and the angular area in which the air outlet openings ( 100 ) are formed in the support tube ( 10 ) is increased with respect to the loop angle of the tubular foil web ( 5 ), and the microporous layer ( 15 ) applied to strip shaped areas of the angular area which are increased with respect to the loop angle of the tubular film web ( 5 ) having an increased air permeability with respect to the air-permeable microporous layer ( 15 ) applied to the remaining areas of the support tube ( 10 ).