System and method for in-mould labelling

A method for in-mould labelling of a plurality of labels to an article, the method comprising:

• casting a first mould piece and a second mould piece movable to a closed position and an open position, wherein the mould is casted in a manner such that in the closed position, the mould defines a mould cavity with an inner shape corresponding to an outer shape of the article to be formed in the mould, and in the open position, any surface of the article on which a label is to be applied remains intact within a single mould piece and the mould is dissected along a diagonal axis of the article, wherein a cross section of a body of the article is polygonal in shape such that each mould cavity defines multiple surfaces;
• placing the mould pieces inside a blow-moulding machine for the opening and closing of the mould during each cycle at a pre-adjusted frequency and width of mould cavity to constantly transport, feed and place a preform in the center of the mould cavity during the open position of the mould in each cycle;
• providing a preform adjuster and installer mechanism to constantly transport, feed and place a preform in the center of the mould cavity during the open position of the mould in each cycle such that air can be blown through the preform during the closed position of the mould;
• arranging a magazine unit comprising a first label magazine to hold labels for the first mould piece, and a second label magazine to hold labels for the second mould piece, wherein the first label magazine and the second label magazine are connected by a common base to ensure a fixed relative positioning, and wherein each label magazine comprises a plurality of label clasping mechanisms protruding from them, and each such protruding label clasping mechanism holds a rim of a label at its end and wherein the length and direction of each label clasping mechanism within a label magazine is configured such that relative positioning of the labels inside the label magazine matches a desired relative positioning of the labels inside the respective mould piece;
• arranging the direction and positioning of gripper surfaces of a plurality of gripper units comprises a first gripper unit and a second gripper unit mounted at the end of each channel, wherein each gripper unit has multiple gripper surfaces equipped and configured to pick one label each from multiple labels in a respective label magazine of the first label magazine and the second label magazine in a manner such that the relative positioning of labels stays intact not only during picking of the label but also during travel of the channel from back to forth position inside the mould opening, and also while placing the labels on inner surfaces of the mould pieces, and wherein at least one of the first gripper unit and the second gripper unit is configured to position a first label on a first surface of a mould cavity of a respective mould piece and a second label on a second surface of the mould cavity of the respective mould piece;
• positioning a robotic arm for picking up labels from the magazine unit and placing them inside the mould pieces during the open position, wherein the robotic arm comprises a label picker unit with a plurality of channels;
• mounting the gripper units on the plurality of channels, wherein each channel has a freedom of back and forth movement along an axis of each of the label magazines to the mould pieces;
• moving the channels with the gripper units with labels to inside the mould opening and positioning against the corresponding surface of the mould pieces which are to be labelled;
• transferring the labels from the gripper units to the inside surface of the mould pieces;
• moving the channels with gripper units back to the magazine for the picking labels for the next cycle;
• closing the moulds and blowing hot air through the preform;
• and
• opening the moulds to let the formed container with in-mould labelling move out of the mould space;
• wherein the total width of the travel of all the channels is less than the width of a mould opening to allow the entry of all channels inside the mould at the same time;
• and
• wherein the placement of labels as well as placement of the preform inside the mould happens simultaneously in each cycle;
• and
• wherein, the axis of movement of channels is selected such that the channels and the labels maintain a distance from the preforms in an assembly line as well as inside the mould, to enable simultaneous placement of multiple labels and the preform inside the mould.