| 摘要 |
A method and machine for producing paperless filter rods for smoking articles, according to which a tow band (11) of hardening-material-impregnated filtering material is fed, by means of porous conveyor (22), along a forming beam (12) having a first portion (29), along which the tow band (11) is injected with steam to cause the hardening material to react, and a second portion (30), along which the tow band (11) is dried with air to obtain, coming out (39) from the forming beam (12), a continuous paperless rigid rod filter (5), which is fed to a cutting device (6); the blowing with steam being performed at a plurality of stabilization stations (45) arranged in series along the first portion (29); and the steam being fed, at each stabilization station (45), into an accumulation chamber (46+47) surrounding a forming channel (36) and communicating with the forming channel (36) through an annular nozzle (61+62) arranged on a transverse plane to the forming channel (36) and having a constant width, measured along an axis (A) of the forming channel (36), of 0.3 to 0.9 mm and preferably equal to 0.7 mm. |
