Abstract: A plastic bag is opened by positive contact with a run of adhesive tape over two guide rolls which are then lifted to raise the upper panel of the bag at locations above spreader bars which can enter the bag in a relatively closed configuration and then spread apart to hold the bag thereon. The spreader bars are then caused to lift the bag from the bag-opening location and to transport it to a bag-loading location leaving the next successive bag at the opening station for contacting with the adhesive tape which has by now been indexed.

Abstract: The invention relates to an "in-chamber" gathering and clipping unit in which the gathering members are rotatable around a common hub and the clip drive punch is driven to advance clips individually from a location coaxially within the hub along a direction radially outwardly onto a bag neck gathered by the gathering members. The radius of the gathering members can be kept short and have their arcuate gathering surfaces so designed that the gathering action takes place within a 90.degree. movement of each of the gathering members, so each gathering member retracts below the hub and still leaves the gathering head narrow in width so it can be incorporated in any one of a wide range of existing vacuum chamber packaging machines.