Patent ID: 8337771

Claim:
A unit for sterilizing a web of packaging material for a machine for packaging pourable food products, said unit comprising: a bath containing a sterilizing agent in which said web is advanced continuously; an aseptic environment containing sterile air, connected to an outlet of said bath, and housing drying means for removing residual sterilizing agent from said web; said aseptic environment comprising an aseptic chamber and a process chamber housing the drying means, the aseptic chamber possessing an interior wall, and the process chamber possessing an interior wall spaced from the aseptic chamber interior wall, wherein said web is shaped into a sealable package inside the aseptic chamber; and wherein said aseptic environment is divided by a narrow-section channel, through which said web travels, into a higher-pressure region including the aseptic chamber and a lower-pressure region including the process chamber, the narrow-section channel being sized to produce a predetermined difference in pressure between the higher-pressure region and the lower-pressure region so as to force air into the channel from the higher-pressure region to the lower-pressure region to dry said web, the narrow-section channel possessing a first open end opening into the aseptic chamber and a second open end opening into the process chamber, and the narrow-section channel possessing a pair of opposing walls, each opposing wall extending between the process chamber interior wall and the aseptic chamber interior wall.