HK1083615A - Process and apparatus for forming tubular labels of heat shrinkable film and inserting containers therein - Google Patents

Description

Method and apparatus for forming tubular labels of heat shrinkable film and inserting containers therein

The object of the present invention is to provide a method for forming tubular labels made of heat shrinkable film and a machine for forming labels and inserting bottles or containers into the formed labels.

The prior art linear machines for applying tubular labels to containers have a low productivity. Another disadvantage of the prior art is that the label is not formed on the labelling machine, resulting in high production costs for the label.

The aim of the present invention is to improve a rotary turret (roundabout) labelling machine of a tubular label labelling machine by forming labels from precut labels made from a rolled film, in order to obtain tubular labels containing said bottles.

The method and machine of the invention provide a number of advantages, the most important of which are:

the cost of a tubular label is the same as the cost of a flat label cut from a reel;

tubular labels can be applied by rotary machines with a higher productivity than known linear machines.

The objects and advantages of the present invention are achieved by a method for forming tubular labels made of heat shrinkable film and a machine for forming and applying said labels to bottles or containers, the characteristics of the invention being defined by the following claims.

The present invention will be better understood from the description of a preferred embodiment shown in the drawings, which are given by way of illustration only, and the invention is not limited to the embodiment shown in the drawings.

FIG. 1 is a simplified plan view showing the machine in general terms;

figures 2 and 3 show the bottom and top of the machine, respectively, separated by line 1-1.

With reference to fig. 1, 1 is a disc, called turntable, which rotates about a vertical axis 2.

On the turntable are mounted a number of small circular plates 3, which small circular plates 3 are rotatable about their respective vertical axes, as will be described later.

4 is an assembly for unwinding the film from a reel, which further comprises a cutter for forming the precut label 100. Since the components are already known, they are not described in detail.

A drum 5 for transferring the precut labels is also known per se provided with a negative pressure zone to absorb the precut labels before transferring them onto the circular plate 3.

Containers or bottles 6 are transferred to the circular plate by means of an inlet star conveyor 7 rotating in the opposite direction to the rotation of the rotary plate, as indicated by arrow 8.

9 is a star conveyor for unloading labeled containers. The star conveyor directs the containers into a known heated tunnel (not shown) to heat shrink each tubular label to adhere it to the outer surface of the respective container.

The heating tunnel can be replaced by a heat-shrink carousel mechanically connected to the star-shaped unloading conveyor 9.

As shown more clearly in fig. 2 and 3, each circular plate 3 comprises: an upper support surface 3a for supporting each container 6; a tubular element 3b, which depends downwards from the surface 3a, the lumen 3c of which communicates with the outer surface through a plurality of evenly distributed holes 10.

The container supporting circular plate therefore has a tubular shape, the sides of which are completely perforated, so that a negative or positive pressure can be created on the surface of the tubular label 100, as will be better described with reference to the operating conditions of the machine.

The tubular circular plate is supported by a shaft 11, a recess 12 defined at the top of which communicates through an aperture 13 with a chamber 14 defined by an outer jacket 15.

The diameter of the chamber 14 is substantially the same as the outer diameter of the tubular round plate so that it can be received when the chamber is moved up and down alternately.

For this purpose, the shaft 11 is abutted by means of a spacer 16 made of a wear-resistant material against a ring cam 17, said ring cam 17 being supported by a surface 18 integral with the frame.

The casing 15 is supported in its entirety by a disc or carousel 1, the disc or carousel 1 being coupled to a shaft 19, the shaft 19 being driven by means of a gear 20, as is known.

A fixed support 21 fixed to the surface 18 supports the shaft 19 by means of a thrust bearing 22.

A fixed air distributor 23 fixed to the support 21 feeds air to a rotating distributor 23a supported by the carousel 1.

The fixed distributor 23 is supplied with air through a pipe 24 and a pipe 25, wherein the pipe 24 is connected with a vacuum pump, and the pipe 25 is connected with a blower (not shown); the rotating distributor 23a delivers air into the duct 26, chamber 1, which in turn supplies air under negative or positive pressure to the holes 10, depending on the position of the rotating distributor.

The cycloid cam 27 rotates the tubular circular plate about its own vertical axis.

The cycloid cam 27 also rotates the gear 28 to mesh with a gear 29 coupled to the portion 11a of the shaft 11.

A groove portion 11a is provided on the shaft 11 so that the shaft 11 can move and rotate around its vertical axis at the same time.

The cycloidal cam rotates the tubular round plate to move the label from the drum to the tubular round plate at a constant speed and stops the tubular round plate for several seconds to seal the spliced end of the label in a predetermined position.

To this end, in the example shown, each circular plate is fixed with a sealing device comprising a bar-shaped heat-sealing device 30 supported by a horizontal sliding guide 31, the horizontal sliding guide 31 being carried by a plate 32 integral with the carousel 1.

The air piston 33 moves the bar heat-seal device 30 from the rest position to a contact position in which the precut label ends are overlapped to form a tubular label.

Power and air are supplied to the heat seal apparatus by two rotary dispensers 34 and 35, respectively.

As shown in fig. 3, the bell-shaped element 40, which is located on the bearing surface 3a, is coaxial with the tubular circular plate 3, this bell-shaped element 40 aligning the bottles 6 on the circular plate with the rotation axis of the circular plate during the passage of the carousel from the star-shaped inlet conveyor to the star-shaped discharge conveyor.

The bell-shaped element 40 is freely supported on a rod 41, the end of the rod 41 being fixed to a piston 42, said piston 42 being slidably mounted in a cylinder 43, which cylinder 43 in turn slides in a jacket 44.

The outer sleeve 44 is supported on a surface 45 integral with the axis 19 of rotation of the turntable, and the outer sleeve 44 defines a slot 46 from which a pin 47 projects, the pin 47 being integral with the cylinder 43 at a first end and supporting a roller 48 at a second end, the roller 48 engaging a cam 49 by the resilient biasing force of a spring 50 inserted in said outer sleeve 44.

The cam 49 is supported on a top surface 51 integral with the machine fixed frame and the profile of this cam 49 is made so as to move the bell-shaped element 40 along a first downward stroke 52, so as to grip the bottles by their stop and insert them along a second downward stroke 53 into the tubular label formed around the tubular circular plate.

This insertion operation is enabled because the tubular round plate is moved downwards simultaneously with the bell-shaped element, for which reason the profile of the cam 17 is made in the form of a cam 49 in the inclined portion of the relevant tubular round plate.

The cam 17 is therefore a device which allows the tubular round plate to be moved downwards by the stroke of transferring the bottles into the tubular labels. The top of the cylinder 43 can be supplied with compressed air in order to move the respective piston and the stem 41 carrying the bell-shaped element to compensate for the difference in height of the bottle with respect to the sample bottle.

The surface 45 can be modified in a known way with respect to the vertical position of the carousel 1 in order to position the machine according to different heights of the various bottles.

The operation of such a machine will now be described.

The bottles are placed on the circular plate 3 by means of a star-shaped inlet conveyor, while the bell-shaped element 40 falls down onto the bottle stop, stopping the bottles firmly on the surface 3a, while allowing them to rotate.

The label is then fed from the assembly 4 and transferred by the drum 5, winding the label around the tubular round plate 3, while the tubular round plate 3 is under negative pressure, so that the label is firmly attracted to the outer surface of the tubular part of the round plate, thus forming a tubular label (called sleeve).

During the formation of tubular labels, the circular plate 3 is rotated by a kinematic mechanism (cyclic mechanisms) connected to the cycloidal cam 27, so as to transfer the labels at a constant speed.

The rotational phase of the rotary drum 5 is different from the rotational phase of the turntable 1; thanks to this feature, in order to maintain the constant speed state, the transfer is carried out at a very small angle compared to the phase state, so that the time required for sealing the end of the tubular label can utilize it.

After the tubular label is formed, when the vertical ends of the label are overlapped and in a predetermined position, the heat-sealing device 30 seals the overlapped ends in a few seconds, thus forming the final tubular label.

At this stage, the heat-seal bar is extracted from the label and high-pressure air is introduced into the chamber 3c, so that air is blown into the hole 10 to disengage the tubular label from the circular plate, so as to lower the bottle-circular plate assembly from the raised position to a position in which the surface 3a is flush with the jacket 15, by means of the cooperation of the cams 17 and 49.

This position coincides with the bottle unloading position and the bell-shaped element 40 will be raised so as to allow the star-shaped unloading conveyor to unload the bottles for the heat treatment to attach the heat-shrinkable labels to the bottles.

After the bottles are unloaded, the cam 17 raises the tubular round plate to a higher position in order to receive a new bottle, starting a new operating cycle.

A plurality of circular plates, with respective heat-sealing bars, centered with the bell-shaped element, are positioned on the carousel; on these circular plates, it is clear that each operating step will be carried out as the turntable rotates,

each heat-sealing system is independently operated by a synchronized motorised valve to ensure accurate sealing according to different angular velocities of the turntable.

The operation of such machines is essentially based on the fact that the precut label is wound on a tubular round plate carrying the bottle to be labelled; the vertical splicing end of the precut label is then heat sealed in a predetermined position to form a tubular label. The label is peeled off from the tubular round plate by means of a jet of high-pressure air, after which the bottle with its round plate can be moved downwards and, once the overlapped vertical ends are heat-sealed, the bottle with its round plate is introduced into the label. The label is then heated to adhere the label to the bottle.

The machine described above can be easily modified to handle bottles of different shapes or sizes by replacing the cycloidal cams to ensure a constant speed of the pre-cut label during transfer from the drum 5 to the tubular round plate, and replacing the tubular round plate and the corresponding disc 3d according to the bottle diameter.

This also makes the machine versatile in that the bottom edge of the label always abuts against the surface of the ring 3 d.

The label ends are joined by sealing in the above description, however, other methods such as chemical sealing or conventional adhesives may be used to join the label ends.

Claims (9)

1. A method for forming a tubular label made of heat-shrinkable film and attaching the label to a bottle or container, characterized in that the bottle or container is inserted into the formed tubular label.

2. A process for forming a tubular label made of heat shrinkable film according to claim 1, comprising the steps of: unwinding and cutting the heat shrinkable film from a reel to obtain precut labels having a length slightly longer than the cross-sectional perimeter of the bottle; transferring pre-cut labels by means of a drum provided with a zone for drawing said pre-cut labels, characterized in that the method further comprises the following steps:

winding the precut label on a rotating tubular plate which supports the container or bottle to be labelled;

sealing the two perpendicular overlapped ends of the precut label in a predetermined position to obtain a tubular label, said sealing step comprising heat sealing or adhesive;

removing the label from the tubular plate and moving the plate and the container thereon so as to insert the container into the tubular label and in the position where the label is to be located;

heating the container to heat shrink the label onto the container.

3. Method according to claims 1 and 2, characterized in that the step of winding the precut label onto the tubular plate is carried out by creating positive and negative air pressure on the side surfaces of the plate.

4. A method according to claims 1 and 2, characterized in that the step of removing the tubular label from the tubular plate is carried out by forming a pressure or air jet on the inner surface of the label.

5. A machine for forming labels and inserting bottles or containers into formed tubular labels, the machine comprising: -a carousel rotating about its vertical axis and supporting a plurality of plates rotating about their respective vertical axis and uniformly distributed over the peripheral area of said carousel, on which the bottles or containers to be labelled are fed from a conveyor, each plate being provided with an idle bell-shaped element for centring and constraining the bottles on said plate during the labelling step, the machine further comprising assemblies (4 and 5) for forming and transferring pre-cut labels made of a rolled film, characterized in that it comprises in turn:

-a plurality of plates (3), each plate comprising: a tubular element (3b) provided with a plurality of holes (10) on its lateral surface, which are connectable to vacuum means for generating a negative pressure during the steps of transferring the precut label and winding said label on said tubular element of the sheet;

-a sealing device (30) movable along the spliced end of the precut label wound on the tubular sheet in proximity to the tubular sheet (3);

-blowing means connectable to said plurality of holes (10) on the lateral surface of the tubular plate for removing the tubular label from said tubular plate;

a lowering device for lowering the tubular plate and the bottles supported thereon into the tubular label.

6. Machine according to claim 5, characterized in that said means for lowering the tubular plate are constituted by a ring cam (17) which supports a rotating shaft (11) carrying the tubular plate.

7. Machine according to claim 5, characterized in that it comprises an additional cam (49) for driving the downward movement of the bell-shaped element from which said plate depends, while the tubular plate is moved downward by means of the cam (17).

8. Machine according to claim 5, characterized in that it comprises a cycloidal cam driving the rotation of the tubular plate through an intermediate kinematic mechanism, said cam being shaped to transfer the pre-formed labels from said assemblies (4 and 5) to said plate (3) at a constant speed.

9. Machine according to claim 5, characterized in that the rotation of the drum (5) has a different phase of rotation than the carousel (1).