A method and apparatus for adjusting the inclination of the label for conical or non-cylindrical containers

Abstract: In a labelling machine for conical or non-cylindrical containers, comprising a cutting station (4) for cutting a film (2) of labels (5) into segments constituting the individual labels to be affixed to the containers, an apparatus for adjusting the inclination of the label (5) comprising an element (7) anchored to an end of the rotating shaft (8) of a roller (3) for feeding the film (2) of labels (5) to the cutting station (4), and in said element (7) is screwed a screw (10) actuated from a knob (11) in such a way as to cause the translation of the element (7) and hence the movement of the rotating shaft (8) of said roller (3) for feeding the film to the cutting station. The method provides, upstream of the cutting station, for the inclination of the direction of feeding of the film.

Description: The present invention relates to a method and an apparatus for adjusting the inclination of the label, in a labelling machine for conical or non-cylindrical containers. Labelling machines are known in which a film constituting the labels, generally made of plastic material such as polypropylene or polyethylene, is wound on a reel from which it unwinds to reach a cutting station where the film is cut into segments, each of which substantially corresponds to a label, which segments are then taken up by an aspirating holed roller which feeds a gluing roller before the final application of the label onto the container. In the case of containers in which the area of application of the label is not perfectly cylindrical but is, for instance, conical or deformed, the label tends to adhere to the container in such a way that the opposite short sides of the label are not perfectly superposed but give rise to a slight offset in height. Document EP 501105 discloses a device for adhering labels to conical circumferential surfaces of objects, especially cups, said device having a label transfer drum having a conical circumferential surface. The drum is set into rotation about its axis and it has suction openings for suction of labels fed indidually from a feed station. The conical circumferential surface of this drum extends in the direction of travel of the sucked labels in an adhesion station next to the conical circumferential surface of a fed object; said object is rotatable about its axis of conicity at circumferential velocities that are substantially equal to the circumferential velocities of the drum in the mutually opposing regions of the object and the drum. The aim of the present invention is to eliminate the aforesaid drawbacks, making available a method and an apparatus that allow to apply film labels also on non-cylindrical, and in particular conical, areas of containers. A further aim is to obtain this in a particularly simple and economical manner and to allow to adjust the positioning of the labels even when the machine is in motion. Said aims are fully achieved by the method and by the apparatus of the present invention, which are characterised by the content of the claims set out below. In particular the method provides, upstream of the cutting station, for having the inclination of the direction of feeding of the film relative to the cutting station. The apparatus comprises means for inclining the label film with respect to the cutting station. Said means preferably comprise an element anchored to an end of the rotating shaft of a roller for feeding the label film to the cutting station. On said element is screwed a screw operated through a knob, and the rotation of the screw causes the translation of said element and hence the displacement of the rotating shaft of the roller that feeds the film to the cutting station. The other end of the shaft of the roller that feeds the film to the cutting station is preferably anchored to a universal joint or to an articulated joint. This and other characteristics shall become more readily apparent from the following description of a preferred embodiment illustrated, purely by way of non limiting example, in the accompanying drawing tables, in which: Figure 1 schematically shows a plan view of the labelling machine; Figure 2 shows a perspective top view of the apparatus; Figure 3 shows a front view of the apparatus. With reference to the figures, the number 1 globally indicates a labelling machine for applying to containers labels obtained from a continuous film 2 that progressively unwinds from a reel that is not shown herein. The film is normally, though not necessarily, a film made of plastic material such as polypropylene or polyethylene, which reaches a roller 3 feeding it to a cutting station 4 where the film is cut into segments or labels 5 by a blade and counter blade. The film segments 5 are in fact the labels to be applied onto the containers. The labels 5 then reach an aspirating holed transferring roller 6, whereto they adhere until their passage to a spreader roller 7 which deposits a linear layer of glue or adhesive substance in correspondence of the two short sides of the label (the label being rectangular). The label is then transferred onto the container in a known manner. The original feature of the present invention resides in the fact that the roller 3 feeding the film to the cutting station is not fixed in the vertical position, but can be inclined in an adjustable manner, even when the labelling machine is in motion. This allows the label to arrive at the cutting station inclined, so as to be cut not in exactly rectangular shape, but to become a parallelogram with the sides that form angles deviating from perpendicularity by a few degrees, for instance 1-3° (for containers with slight conicity). This is sufficient to compensate for the conicity of the container (and for the fact that the label tends to rise inclined thereon) and to cause the two short sides of the label to match perfectly during the superposition that takes place when the label is applied to the container. Obviously, the roller 3 shall be inclined in the opposite direction to the direction towards which the label tends to incline during its application onto the container. The roller 3 originally comprises adjusting means constituted by an element 7 formed by a plate 7a and by a block 7b, mutually integral (and preferably welded to each other). The plate 7a is holed to receive a first end of the shaft 8 of the roller 3, whilst the second end of the shaft 8 is anchored to an articulated joint 9, preferably a universal joint. The block 7b has a hole with threaded horizontal axis into which is inserted a screw 10, manually actuated from a knob 11. According to the method of the present invention, through the knob 11 it is possible, even with the machine in motion, to rotate the screw 10 and hence to translate the upper end of the roller 3 in such a way as to move the axis of the roller relative to its normal vertical lay. Normally, for containers of slight conicity, an offset of about 1-3° is sufficient. In this way the film enters the cutting station inclined (relative to the usual horizontal direction of feeding) and the label is cut in the shape of a parallelogram, instead of a perfect rectangle. The inclination relative to the vertical may be adjusted in both directions depending on whether the label on the bottle is offset in height above or below a horizontal reference line. Obviously, the apparatus may be employed also for cylindrical or otherwise shaped containers and the offset may be applied to any of the film transferring rollers located before the cutting station 4. According to a possible variation not illustrated herein, instead of the knob 11, an electric motor may be provided, for instance of the stepped kind, able to be supplied power through a pushbutton panel controlled by an operator, or automatically by means of a device able to measure the height offset of the label placed on the container. The reader device will send the signal to a processor which compares the signal with a sample signal and in case of deviation will cause the motor to rotate in one direction or the other depending on whether the height offset is greater or smaller.

Claims: A labelling machine for cylindrical, conical or otherwise shaped containers, comprising a cutting station (4) for cutting a film (2) of labels (5) into segments constituting the individual labels to be affixed to the containers and at least a roller (B) before the cutting station (4), characterised in that it comprises means (7, 9, 10, 11) for inclining a roller (3) before the cutting station with respect to its vertical position in order to incline the film (2) of labels (5) with respect to the cutting station (4). An apparatus as claimed in claim 1, wherein said means comprise an element (7) anchored to an end of the rotating shaft (8) of a roller (3) feeding the film (2) of labels (5) to the cutting station (4), in said element (7) being screwed a screw (10) actuated from a knob (11), the rotation of the screw (10) causing the translation of said element (7) and hence the movement of rotating shaft (8) of said roller (3) feeding the film to the cutting station. An apparatus as claimed in claim 2, wherein the other end of the shaft (8) of the roller (3) feeding the film to the cutting station (4) is anchored to a universal joint or to an articulated joint (9). An apparatus as claimed in claim 2, wherein an electric motor is provided for rotating the screw (10), supplied power by an operator through a pushbutton panel or in automatic through a device able to measure the height offset of the label. A method for adjusting the inclination of a film (2) of labels (5) in a labelling machine for conical or non-cylindrical containers, comprising a cutting station (4) for cutting said film (2) of labels (5) into segments constituting the individual labels to be affixed to the containers and at least a roller (3) before the cutting station (4), characterised in that upstream the cutting station (4) said film (2) of labels (5) is inclined with respect to the cutting station (4) by inclining a roller (3) before the cutting station with respect to its vertical position.

Inventors: PIAZZA GASTONE, PIAZZA, GASTONE
Applicants: SIG ALFA S P A, SIG ALFA S.P.A.
Application year: 2001
Main classification: B65C9
IPC codes: B65C9