(57) Containers (19) (made of, for example, metal, glass, plastic or fiber) are sterilized
in a sterilizer (21) of packaging apparatus having a helical or spiral conveyor belt
(36) within an insulated casing (31) through which air above atmospheric pressure
at up to about 500 °F (260 °C) is circulated by means of a heater (46) and blower
(47), in a recirculation path. The containers then travel along a straight-line encased
conveyor (22) where sterile air above atmospheric pressure prevents ingress of non-sterile
ambient air. During part of the path through the straight-line conveyor, the containers
are driven by a helix (71) which forces the containers into close proximity. Pre-sterilized,
preferably cooled, product is delivered into the containers preferably through a curtain,
slit-type filler (111). The speed of the containers is timed so that the desired product
volume is delivered into the containers. Thereafter, filled containers are accepted
by a container closing machine (24). Container lids (18) or covers are sterilized
in a section of the apparatus where lids are moved along a conveyor and sterile air
which has been heated is forced by a blower (161) into the lid sterilizer section.
The lids then travel up a tunnel at greater than atmospheric pressure, where they
are cooled and delivered to the closing machine. The closing machine applies the sterile
lids to the containers at greater than atmospheric pressure.
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