Patent ID: 7300018

Claim:
A method for stabilising high speed running of a metal band along a longitudinal running direction, the band ( 4 ) being applied from a line of contact ( 30 ), over at least one angular sector of rotary revolution surface ( 3 ) around an axis ( 20 ) crosswise to the running direction, and connecting tangentially to the rotary surface ( 3 ) while forming, on the upstream side in the running direction, a dihedron (G) delineated, on one side by an outer face ( 31 ) of the rotary surface ( 3 ) and on the other side, by an inner face ( 41 ) of the band ( 4 ) along which a portion of the surrounding air forms a boundary layer ( 43 ) trapped with the band ( 4 ) toward the line of contact ( 30 ), a the method comprising positioning a device upstream of a spool ( 3 ) for winding the band into superimposed spires, in order to prevent the trapping of air between the spires ( 31 , 32 ), providing the device as a hollow deflecting member ( 5 ) having a hollow profile; modifying the conditions of circulation of the air in the upstream dihedron (G) the hollow deflecting member ( 5 ) having a first face ( 50 ) directed toward the inner face ( 41 ) of the band ( 4 ) and a second face ( 50 ′) directed toward the outer face ( 31 ) of the rotary surface ( 3 ), tilting the first face ( 50 ) of the deflecting member ( 5 ) toward the inner face ( 41 ) of the band ( 4 ), in the running direction thereof, in order to decrease gradually the passageway section of the air trapped with the band, along the inner face ( 41 ) thereof, thereby causing an increase in the pressure of the air trapped in the convergent (C 1 ) thus formed, with respect to the pressure prevailing inside the hollow deflecting member ( 5 ) which communicates with the convergent C 1 by at least one orifice ( 55 ) provided in said tilted face ( 50 ) and with the outside, the differential pressure thus created determining the exhaust toward the outside of a certain air flow rate passing through said orifice ( 55 ) and the separation of the remaining portion of the air mass constituting the boundary layer ( 43 ), installing the deflecting member ( 5 ) of the air on a supporting means ( 6 ) adjustable in length and angle relative to the diameter of the spool ( 3 ), and maintaining the deflecting member ( 5 ) in an optimum position with respect to the inner face ( 41 ) of the band ( 4 ), as the band is wound gradually onto the spool.