Labeling machines of the type described above are illustrated by U.S. Pat. No. 4,108,709; also by other turret type labeling machines which are on the market. Referring to U.S. Pat. No. 4,108,709, the disclosure of which is incorporated herein by reference, each container in its turn is gripped between upper and lower chucks which are caused to spin about their common axis as the turret rotates about the turret axis. As each container reaches a line of tangency with the vacuum drum the leading end of the label on the drum is adhered to the container by an adhesive, vacuum is released from the drum surface so that the label may follow the container and wrap around it and, as the container recedes from the line of tangency with the vacuum drum, there is a segment of the label between the line where it comes into contact with the container and the line where it is still in contact with the vacuum drum. Finally, as the label becomes completely detached from the vacuum drum there is a loose end to the label which is attached to the spinning container but not to the drum, such loose end being commonly referred to as a "flagging" end.
Such unattached or flagging segments of labels are ultimately wrapped around a container, either completely as in full wrap or partially as in what is known as a "spot label". The trailing end of the label is adhered to the container by an adhesive in the case of a spot label or it overlaps and is adhered to the leading end of the label by an adhesive in the case of a full wrap.
It will be understood that segments of sheet material other than labels, for example decorative or protective sheets may be used and that the articles need not be containers. It will also be understood that, although the containers are generally cylindrical in shape, their shapes may depart from cylindrical. For simplicity "labels" and "containers" are described below and the containers are generally described as cylindrical.
In labeling machines of this type difficulties are encountered due to the freedom of movement of the unattached segment or flagging end of the label and its tendency to undergo random motion. This is particularly troublesome with lightweight, thin, limp plastic labels and/or at high speeds of labeling.
USPTO Backgrounds
USPTO Backgrounds