Method and apparatus for removing air from an article-filled bag with oscillating rings

A method of removing air from a bag configured for accommodating at least one article while the bag is traveling on a moving conveyor belt of a conveyor system, comprising:

• advancing the bag having a first sealed end and an opposite second open end, on the conveyor belt toward a plurality of rings in a direction of belt travel, each said ring having a centered opening dimensioned to loosely accommodate a horizontal shaft, each ring separated from said shaft by a space defined by an inner surface of each said ring and an outer surface of said shaft without having any intervening material directly and consistently engaging the inner surface of each said ring and the outer surface of said shaft;
• loosely rotating said rings relative to said shaft so that each said ring freely rotationally oscillates relative to said shaft in an orbital motion about said shaft;
• providing the bag on the conveyor belt, the bag having the first sealed end and the opposite second open end, the at least one article in the bag defining a contour, said rings being constructed and arranged so that said rings independently and substantially follow the contour of each article to expel air from the second end of the bag;
• and
• depressing an outer surface of the bag solely caused by weight of each ring while the bag is carried on the conveyor belt beneath said rings.