The present invention is related to an apparatus and method for orienting a tubular heat- shrinkable sleeve relative to a container.

During the manufacturing and packaging of goods, labels may be attached to packages or containers holding the goods. For instance, in the beverages industry, labels may be placed around containers or bottles to indicate the contents thereof, to indicate the brand name, etc. Similar applications can be found in non-food industries, more in particular in the field of cosmetic products. A shampoo container may be provided with a label indicating the specific type of shampoo etc.

One particular type of label is a sleeve-like label, also referred to as a sleeve. A sleeve may be a tubular piece of thin foil material that may be moved over the upper or lower end of the container. A sleeving system configured to apply a sleeve-like label over a number of containers is described in European patent EP 2 949 451 Bl , incorporated herein by reference for all purposes. When the sleeve is arranged in this manner over the outer surface of the container, the sleeve may be partially or fully attached to the container. When use is made of heat-shrinkable sleeves, a sleeve arranged around a container may be attached to the container by applying heal to the heat- shrinkable sleeve material causing the sleeve to shrink, thereby attaching itself to the outer surface of the container.

After a sleeve has been (loosely) arranged over the container, the position of the sleeve on the sleeve is to be checked in order to determine whether the position is correct and the sleeve can be directly attached to the container. If the container is not arranged at exactly the right position, the orientation of the sleeve needs to be changed until the sleeve has arrived at the right position. Only when the oriented or repositioned sleeve is at the correct position, the sleeve is allowed to be attached to the container.

As mentioned, once a sleeve has been arranged around a container, the sleeve is to be positioned correctly relative to the container and then the sleeved containers is exposed to heat that causes the heat-shrinkable material of the sleeve to shrink so that the sleeve is attached to the container. The application of sleeves around containers and the subsequent (re-) positioning and attachment of the sleeves are typically performed in a high speed - high throughput sleeving process. In this sleeving process the containers are transported on one or more conveyors of a conveyor unit, for instance one or more conveyor belts on which the containers have been placed, and guided along a sleeving station wherein sleeves are applied around the containers passing by, for instance by shooting a sleeve a position above or below the container downward or upward to arrange the sleeve loosely around the outer surface of the container, an orientation station wherein the orientation (i.e. the position) of the sleeve that has been arranged around the container, is changed relative to container until the sleeve is oriented at the correct position on the container, and an oven or similar heating device for applying heat to the container and its sleeve so that the sleeve is shrink-fit around the container.

It is important that the sleeve fixedly attaches itself at an intended and correct position on the container. For instance, it is important that the angular orientation of the sleeve with respect to the container is accurate. Here, within the context of the present disclosure, the term "angular orientation" is defined relative to an imaginary axis perpendicular to the conveyor belt that is used to transport the containers. In the present disclosure this imaginary is sometimes referred to as the "longitudinal axis" of the container.

Systems are known for mutually orienting the sleeve and container. In a first type of systems the container is moved, more in particularly rotated, to position the container such that the sleeve, which is assumed to have a well-defined orientation, can be placed accurately on the container. Typically, in case the containers are transported on the conveyor belt of a container conveyor unit containers may be gripped at their top side, for instance at the lid or cap of the container. Separate means may be provided to rotate the container while holding the sleeve in place. It is also possible to arrange two conveyor belts sideways of the container and cause the conveyor belts to move in opposite directions and/or at a different speed as the main conveyor belt on which the container is transported. Consequently, as the container is transported by the main conveyor belt, the container is rotated by the two oppositely arranged conveyor belts so that the container may become suitably oriented with respect to the sleeve. This type of systems has a number of disadvantages. For instance, especially in case of relatively heavy containers (for instance, pre-filled containers), the mass to be rotated is relatively large. It may cost some time to rotate the container and/or the container may be caused to tumble so that the maximum attainable throughput may be limited.

In another type of systems the sleeve rather than the container is moved, more specifically rotated, relative to the container in order to orientate the sleeve with respect to the container. One example of a system of this type is disclosed in EP 3 015 379 Al, incorporated herein by reference for all purposes. In this known system a sleeve orientation unit is provided that is configured to rotate a sleeve once is has been arranged around the container. The sleeve orientation unit comprises a horizontal conveyor for transporting a number of containers in a transport direction and two upright side conveyor belts being moveable in a direction parallel to the transport direction. Once the sleeve has been arranged around a container (and not yet been fully attached to the container by the above-discussed heating process), the sleeve is held against both side conveyor belts and the side conveyor belts rotate the sleeve relative to the container in dependence of an angular position difference between the container and the sleeve. The sleeve can be held against a side conveyor belt by using a vacuum unit. The vacuum unit comprises a vacuum pump connected to a vacuum chamber. The vacuum chamber has an open inlet that is partially covered by a side conveyor belt so as to allow the application of a suction force through that part of the open inlet that is not covered by the support surface. In examples wherein the side conveyor belt is perforated, the belt may be arranged so as to allow the suction force to be exerted through these perforations of the belt as well.

The sleeve orientation unit of EP 3 015 379 Al provides a sleeving system that enables a high speed sleeving with high accuracy.

The rotation of the sleeve depends on many factors, such as timing of vacuuming, unstable suction force, duration of attaching the label to the supporting conveyor belt, etc. It is desirable to be able to control these factors even more accurately so as to further improve the accuracy of the sleeving process.

The overall speed of the sleeving process (the sleeving process including at least the steps of applying sleeves (loosely) around containers, orienting the sleeves relative to the containers and attaching the oriented sleeves to the containers) is dependent on different factors as well. For instance, the speed may be dependent on the time interval that is needed to change the suction force and to create a suitable vacuum atmosphere around a sleeve orientation unit. This may also have an impact on the accuracy of the orientation of the sleeves and/or on the opportunities for allowing a rapid transportation of the containers and therefore a high-speed sleeving process.

Another issue is that the quality of the sleeve once attached to the container (by the heat shrinking operation) sometimes varies from container to container. An even more constant quality of the sleeve is desirable as well.

It is an object of the present invention to provide an improved apparatus and method. It is a further object of the present invention to provide a high speed and high accuracy apparatus and method for orienting sleeves relative to containers and/or to provide a high speed and high accuracy sleeving system for arranging and orienting sleeves around containers.

According to a first aspect, this object may have achieved with an apparatus for orienting a tubular heat-shrinkable sleeve relative to a container that is being transported along a transportation path in a transport direction and around which the heat-shrinkable sleeve has been arranged, wherein the sleeve has not yet been finally shrunk, the apparatus comprising at least one sleeve orientation unit arranged at either side of the transportation path, the sleeve orientation unit comprising:

- a sleeve supporting conveyor belt being arranged alongside the transportation path and configured to support the sleeve along a predetermined length along the transport direction, the sleeve supporting conveyor belt being moveable in one or more directions parallel to the transport direction and having a number of perforations; - at least one sleeve supporting conveyor belt drive unit for driving the movement of the supporting conveyor belt;

- a vacuum unit configured to hold the sleeve against the supporting conveyor belt;

wherein the apparatus is further configured to orient the sleeve relative to the container by rotating the sleeve relative to the container in dependence of an angular position difference between the container and the sleeve by moving the supporting conveyor belt of the sleeve orientation unit while the sleeve is held against the supporting conveyor belts; and

wherein the vacuum unit comprises a housing forming a vacuum chamber connectable to a vacuum pump, said housing having an open inlet fully covered by the perforated sleeve supporting conveyor belt so as to apply a suction force only through one or more of the perforations in the supporting conveyor belt, wherein the sleeve supporting conveyor belt drive unit comprises a first rotating element and a second rotating element spaced apart along the transport direction and along which the sleeve supporting conveyor belt is wound, wherein the length of the open inlet of the vacuum chamber in transport direction is equal to or smaller than the distance between the first and second rotating element.

The inventors have found that by configuring the open inlet such that the length thereof is equal to or smaller than the distance between the first and second rotating element and by having the open inlet of the housing fully covered by the perforated supporting conveyor belt, the suction provided by the vacuum unit is applied in a very accurate manner and only through the perforations in the sleeve supporting conveyor belt. In essence no further suction flow bypassing the flow through the perforations is generated. In this manner the process of holding the sleeve against to sleeve supporting conveyor belt can be belter controlled and/or the accuracy of the positioning of the sleeve on the outer surface of the container may be improved as well. Tests have demonstrated that in this manner a more accurate determination of the period in which the sleeve is held by the supporting conveyor belt can be achieved. This may result in an even more accurate positioning of the sleeve relative to the container.

The container may be transported along a transportation path in a transport direction by a container conveyor unit. The container conveyor unit may comprises a conveyor (for instance including a moveable conveyor belt) arranged for carrying the bottom end of a container for transporting the container in the transport direction. While in embodiments of the present disclosure the container conveyor unit only has one conveyor arranged to carry thereon the containers, in other embodiments the container conveyor unit also comprises a further (second) conveyor (for instance a conveyor having a second moveable conveyor belt) arranged above the first moveable conveyor belt so as to hold the upper end of the container. In the latter embodiments the containers are transported in the transport direction while being held between the lower and upper conveyor. Further details about the container conveyor unit are provided hereafter. The containers are being transported along the transport direction in either continuous or an intermittent manner and the orienting of the sleeve may be performed when in the periods wherein the transport is halted or during movement of the container in the transport direction (orienting the sleeve "on the fly")- The apparatus could furthermore comprise a determining unit for determining an angular position difference between the container and the sleeve, preferably relative to an axis perpendicular to a conveyor belt of the conveyor unit. For instance, when the angular position difference is determined relative to an axis of the conveyor belt of a lower (first) conveyor, the angular orientation may be defined relative to an axis perpendicular to the flat upper surface of the conveyor belt. However, the angular orientation may also be defined relative to another axis, for instance relative to the flat lower surface of a conveyor belt of an upper conveyor or relative to the longitudinal axis of a sleeve that is discharged downward or upward to be loosely arranged around a container.

Prior to orienting the sleeve relative to the container, the heat shrinkable sleeve is only arranged loosely around the container and has not yet been finally shrunk. In some applications, the sleeve may nevertheless be somewhat attached to the container not excluding the case in which a small part of the sleeve has been shrunk to keep the sleeve temporarily in place, i.e. during transport. In this situation, the process of orienting the sleeve relative to the container in accordance with the present invention breaks the attachment between sleeve and container. Then, after the sleeve is properly orientated relative to the container, it may be finally attached to the container, for instance by heat shrinking the sleeve in an oven or a heat tunnel.

In an embodiment the sleeve supporting conveyor belt in contact with the suction mouth has a straight portion which runs parallel to the transportation path. The (length of the) straight portion corresponds to the length of the open inlet.

In further embodiments of the present disclosure the open inlet of the vacuum chamber is formed by a suction mouth. The suction mouth has an essentially rectangular cross-sectional shape. Alternatively or additionally, the suction mouth may have a circumferential free edge configured to contact the sleeve supporting conveyor belt transported along the suction mouth or to at least guide the sleeve supporting conveyor belt along the suction mouth. In this manner the risk of air flows sucked in by the vacuum unit through other openings than the perforations in the sleeve supporting belt(s) is reduced.

In a particular embodiment the housing is configured such that the distance between the first and second rotating element is the distance in longitudinal direction between the axis of rotation of the first rotating element and the axis of rotation of the second rotating element. In this manner a well-defined holding period wherein the vacu m unit holds the sleeve against the supporting conveyor belt, may be determined. In case the holding period can be determined with a higher accuracy, also rotation of the sleeve to attain the correct end position of the sleeve on the container wall can be performed in a better-controlled manner so that the positioning of the sleeve may be improved.

In an embodiment of the present invention the apparatus comprises a control unit configured to determine a speed at which the sleeve supporting conveyor belt of the at least one sleeve orientation unit moves and/or a holding time during which the sleeve is held against the at least one supporting conveyor belt of the at least one sleeve orientation unit based on the determined angular position difference and to control the at least one vacuum unit and/or the at least one sleeve supporting conveyor belt drive unit using the determined holding time and/or speed.

According to another aspect of the invention an apparatus for orienting a tubular heat- shrinkable sleeve relative to a container that is being transported along a transportation path in a transport direction and around which the heat-shrinkable sleeve has been arranged is provided. The apparatus may comprise:

a container conveyor unit for transporting the containers along the transportation path; a determining unit for determining an angular position difference between the container and the sleeve;

at least one sleeve orientation unit arranged at either side of the transportation path, the sleeve orientation unit comprising

- a sleeve supporting conveyor belt being arranged alongside the transportation path and configured to support the sleeve along a predetermined length along the transport direction, the sleeve supporting conveyor belt being moveable in one or more directions parallel to the transport direction and having a number of perforations;

- a sleeve supporting conveyor belt drive unit for driving the movement of the supporting conveyor belt;

- a vacuum unit configured to hold the sleeve against the sleeve supporting conveyor belt;

wherein the apparatus is further configured to orient the sleeve relative to the container by rotating the sleeve relative to the container in dependence of an angular position difference between the container and the sleeve by moving the at least one supporting conveyor belt of the at least one sleeve orientation unit while the sleeve is held against the at least one supporting conveyor belts;

wherein the conveyor unit comprises:

a first conveyor having a first moveable conveyor belt arranged for carrying the bottom end of a container for transporting the container in a transport direction;

a second conveyor having a second moveable conveyor belt arranged above the first moveable conveyor belt so as to hold the upper end of the container; a conveyor drive for driving the first and second conveyor, wherein the conveyor drive is configured to move the first and second moveable conveyor belt at the same speed.

By transporting the containers on a conveyor unit wherein at the same time both the upper end of the container and the bottom end of the container are transported, the accuracy of the sleeve orienting operation may be increased. The risk of a container tumbling over or shifting from its position on the conveyor unit during the orienting of the sleeve can be reduced and the exact position of the container on the conveyor unit can be better controlled during the entire transportation operation.

As discussed above, the sleeve orientation unit is configured to rotate the sleeve relative to the container in dependence of an angular position difference between the container and the sleeve determined by the determining unit by moving the support surface while the sleeve is held against the support surface. During operation, the sleeve will be held against the one or more sleeve supporting conveyor belts, whereas the container will generally not touch the support surface. Furthermore, the sleeve may move at a different speed along the transport direction than the container. Due to this difference in speed, the container may at some point in time hit the sleeve either at the front or back side of the container. If the sleeve is released at or just prior to that point in time, the sleeve will return to a position around the container in which the angular position relative to the container has been changed. The amount of change in angular position can be determined by varying the holding time during which the sleeve is held against the support surface and/or the speed of the support surface. It is also possible to not move any of the sleeve supporting conveyor belts at all, in which case the holding time is relatively short due to the large difference in speed between the sleeve supporting conveyor belts and the conveyor belt.

According to another aspect an apparatus for orienting a tubular heat-shrinkable sleeve relative to a container is provided wherein the apparatus comprises a container conveyor unit for transporting the containers along a transportation path, the container conveyor unit comprising:

- a conveyor having a moveable perforated conveyor belt arranged for carrying the bottom end of at least one container for transporting the container in a transport direction;

- a vacuum system comprising a vacuum element arranged below the perforations in the moveable perforated conveyor belt and a vacuum pump connected to the vacuum element;

wherein the perforations are distributed in longitudinal direction along the moveable perforated conveyor belt so as to apply a downward suction force on the bottom end of the at least one container.

This apparatus is especially suitable for handling lightweight containers and/or when the diameter of the label width is small. In other words, the conveyor works particularly well in situations wherein the inner circumference of the sleeves is relatively close to the outer circumference of the container. In a preferred embodiment the vacuum element comprises a vacuum box. The vacuum box may be arranged alongside an orientation unit. In embodiments wherein use is mare of two or more orientation units the vacuum box may be arranged between the sleeve orientation units.. The vacuum box may be a stationary box extending from a position upstream of the sleeve orientation units to a position downstream of the sleeve orientation units. This means that when the sleeve of the container being transported on the container conveyor unit is oriented by one or more of the orientation units, the container is held firmly against the container conveyor belt as a result of the downward suction force created by the vacuum (i.e. the low pressure) inside the vacuum box. In a specific embodiment the vacuum box has an upper elongated opening extending below the perforations in the moveable perforated conveyor belt so as to restrict the suction action to the area wherein the perforations in the container conveyor belt pass by the vacuum box.

In a further embodiment the perforations are arranged in an array of perforations extending in transport direction. The array may consist of one row of perforations, but could also include a plurality of perforations, for instance a plurality of parallel rows of perforations. The array of perforations may extend along a center line of the container conveyor belt so that the containers may be held in the center of the container conveyor belt.

Furthermore, the mutual distance in longitudinal direction between consecutive perforations may be smaller than the minimum dimensions of the container in cross-section. This guarantees that the bottom end of a container arranged on an arbitrary longitudinal position on the conveyor belt is always held on the container belt by at least one perforation. In other embodiments wherein use is made of a second container conveyor belt above the first container conveyor belt a further vacuum system may be provided to additionally hold the container at the upper container end by an upward suction force.

In embodiments of the present disclosure a water supply device is provided to supply water to the outer surface of a sleeved container to cause the sleeve to adhere to a part of the container outer surface. Preferably the supply of water is in the form of water droplets sprayed towards the sleeved container. The water droplets are relatively small and can be distributed more or less evenly over at least a part of the container outer surface so that a "sticky" part of the container outer surface is created. Furthermore the spraying of water (droplets) enables high speed operation of the system. The water supply device then may be a water spray device configured to spray water towards the sleeved container so as to provide water droplets in the interspace between the sleeve of the sleeved container and the container outer surface. However, other types of water supply devices can also be used, for instance water supply devices wherein use is made of one or more wet brushes, for instance rotating circular brushes, wet sponge, water dripping unit to apply water droplets to the inner side of the sleeve and/or outer side of the container. In order to ensure the possibility to orient the sleeve and therefore move the sleeve relative to the container, the water should be applied to the container only after the orienting process has been completed. In embodiments of the present disclosure the water spray device is therefore arranged at the axial position of the at least one sleeve orientation unit or downstream thereof. In the first position the water spray device should be controlled to spray water only after the orientation unit(s) has/have completed their orientating task, while in the latter situation the sleeve of course already has been oriented. As to the height position of the water spray device, more specifically the nozzles thereof, the water spray device should be arranged at a position to spray water upward or downward in the direction of the position of the sleeved container. This means that the water spray device should be positioned at a height below the bottom of the container or at a height higher than the top of the container. Preferably the nozzles are arranged above the container top so that water droplets moving downward over the containers outer surface under the influence of gravity enter the interspace between the sleeve and container surface.

The water spray device may comprise a single nozzle for spraying the water towards the container. In other embodiments the water spray device comprises a plurality of nozzles arranged to spray water towards the container from different positions. The nozzles may be evenly distributed at equidistant positions relative to a perimeter of the sleeved container so that a proper spray pattern on the contain outer surface is achieved and to increase the reliability of the positioning of the sleeve.

In various situations the container transported by the container conveyor may be held in a fixed orientation relative to the container conveyor (for instance in a fixed position on a conveyor belt of the container conveyor) and the orientation of the container is known. The orientation may be known a priori by making use of stationary guiding elements that are positioned to engage the outer surface of the containers when they are passed along the guiding elements in such a manner that the containers carried are moved into a fixed and mutually aligned orientation relative to the container conveyor. However, there may be situations wherein such fixed and aligned orientation is difficult to realize, for instance in situations wherein the container has a circular cross-section. This may lead to problems in identifying the correct attachment position of the sleeve around the container, especially in cases wherein the containers have been provided with external features such as a hinge cap, that may influence the correct attachment position.

In embodiments of the present disclosure therefore the apparatus comprising a determining unit for determining an angular position difference between the container and the sleeve may have at least one determining unit comprising:

- a detection unit configured to detect the angular position of the container and to detect the angular position of the sleeve; - a distance determining unit configured to determine the distance over which the sleeve is to be rotated, preferably also the rotational direction in which the sleeve is to be rotated, to correctly orientate the sleeve relative to the container, based on the detected angular positions of the container and the sleeve;

- a control unit configured to control the at least one orientation unit to rotate the sleeve over the determined distance, preferably in the determined direction over the determined distance.

In these embodiments the distance is based not only on the orientation of the sleeve (for instance determined by the position of a sleeve orientation identification feature), but also on the orientation of the container itself (for instance determined by the position of a container orientation identification feature). The distance may be the length the sleeve is to be moved over the outer surface of the container (by rotation) to reach the correct orientation and thus corresponds to the distance the sleeve supporting belt must travel to properly rotate the sleeve relative to the container.

In embodiments of the present disclosure the detection unit comprises:

- a first detector arranged to detect the angular position of the container;

- a second detector arranged to detect the angular position of the sleeve.

The first detector may be a (first) camera arranged to capture an image of the sleeved container from a position above or below the container and/or the second detector may be a (second) camera arranged to capture an image of the sleeved container from a position sideways of the sleeved container. The captured image(s) of the first camera may be used to determine the position of a container orientation identification feature such as the hinge of a hinge cap provided on the container, while the captured image(s) of the second camera may be used to determine the position of a sleeve orientation identification feature.

The distance determining unit may further be configured to calculate the distance based on the angular positions of both the container and the sleeve and on container circumference information. The container circumference information is representative of the container circumference, more specifically of the relation between the determined angular positions and the corresponding distance over the outer surface of the container. In case of a container with a circular cross-section, the distance (d) may be calculated as: d = pi * container diameter * (difference in angular position /360), as will be elucidated later. The container diameter may have been pre- stored, for instance in the distance determining unit. Alternatively or additionally, the container diameter can be determined from the image made by a camera (i.e. the above-mentioned first camera).

According to another aspect a sleeving system for sleeving a plurality of containers is provided, wherein the sleeving system comprise:

- a sleeving device for arranging sleeves around containers; - an apparatus for orienting a tubular heat-shrinkable sleeve relative to a container as defined herein; and

- a heating unit for applying heat to the sleeved containers so as to fully attach the sleeves to the containers by heat-shrinkage.

The sleeving system may comprise one or more support elements arranged between the sleeving device and the apparatus for orienting the sleeve, the support elements being arranged alongside a container conveyor in order to support the sleeve of a sleeved container.

Further characteristics of the present invention will be elucidated in the accompanying description of various preferred embodiments thereof. In the description reference is made to the annexed figures.

Figure 1 illustrates a schematic overview of a system for sleeving a number of containers, the system including an embodiment of an apparatus for orienting a tubular heat-shrinkable sleeve relative to a container;

Figure 2 illustrates a schematic overview of an embodiment of the apparatus for orienting a tubular heat-shrinkable sleeve relative to a container;

Figure 3 is a partly taken away view of an embodiment of a sleeve orientation unit;

Figures 4A-4F depict various stages of an exemplifying sleeving operation;

Figure 5 illustrates a partly taken away view of a further embodiment of an apparatus for orienting a tubular heat-shrinkable sleeve relative to a container;

Figure 6 ill strates a partly taken away top view of a still further embodiment of an apparatus for orienting a tubular heat-shrinkable sleeve relative to a container;

Figure 7 illustrates a schematic side view of the apparatus of figure 6;

Figure 8A illustrates a side view along the transport direction (PT) of an embodiment of a water spray device for applying water to a container, including a container and a parts of the sleeving system 1 ;

Figure 8B illustrates a similar view perpendicular to the transport direction of the containers of the water spray device of figure 8A;

Figure 8C illustrates a top view of the embodiment of figures 8A and 8B, including the container on which water is to be applied;

Figure 9 illustrates a schematic overview of a sleeving system including the embodiment of the water spray device of figures 8A-8C;

Figure 10A illustrates a side view of a detection system for detecting the orientation of a container and the orientation of a sleeve arranged around the container;

Figure 10B illustrates a top view of the embodiment of figure l OA;

Figure IOC is a view of an image taken by one of the cameras of the detection system according to figures lOA and 10B; and Figure 1 1 illustrates a schematic overview of a sleeving system including the embodiment of the detection system as shown in figures 1 OA- I OC.

In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, that the present invention may be practiced without these specific details. In other instances, well-known structures and devices are not described in exhaustive detail, in order to avoid unnecessarily obscuring the present invention

It is noted that, as used herein and in the appended claims, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. It is further noted that the claims may be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for use of such exclusive terminology as "solely," "only" and the like in connection with the recitation of claim elements, or use of a "negative" limitation.

As will be apparent to those of skill in the art upon reading this disclosure, each of the individual embodiments described and illustrated herein has discrete elements, components and features which may be readily separated from or combined with the features of any of the other several embodiments without departing from the scope of the present invention. Any recited method can be carried out in the order of events recited or in any other order which is logically possible.

Figure 1 illustrates a schematic overview of an example of a sleeving system for attaching sleeve-like labels (herein also referred to as sleeves) to a row of containers. The sleeving system 1 comprises a sleeving (labelling) device 2 for arranging sleeves around containers 3 travelling on a conveyor of a container conveyor unit 6. The containers 3 could be supported on any type of a conveyor, for instance a driven endless conveyor belt 7 as shown in figure 1. The sleeves comprise of foil material stored on a foil roll 8 provided in a foil stock 9. The foil material 10 can be formed by a flattened tubular foil material, preferably of a heat shrinkable type, that is fed (step S 1) from the foil stock 9 to a foil buffer 11. Buffer 11 allows buffering (step S2) of the foil material, e.g. when a roll 8 is to be replaced by a new roll of material in order to provide a continuous feed 12 of flattened tubular foil material to a stationary spreading unit 13. The spreading unit 13 is mounted to a frame 14, more specifically is supported by several sets of drive wheels. One set of drive wheels 15 only is shown in figure 1. The spreading unit 13 comprises an elongated mandrel 16. In recesses in the mandrel a first set of opposing wheels or rollers 17 and a second set of opposing wheels or rollers 18 have been provided. The mandrel is supported on the frame, for instance on the drive wheels 15 thereof.

The flattened foil material 10 is opened (step S3) using the upper tip 20 of the mandrel 16. The tip forms the inlet side of the mandrel 16 and is configured as a flat element that widens in downstream direction (direction P _d ). The next part of the mandrel is formed by a number of mandrel elements configured to further move (step S4) the foil material downward, form individual sleeves by cutting the opened foil material using a cutting unit 21 into individual sleeves, and to discharge (step S5) the individual sleeves towards the containers 3 (in downward direction 19) passing by on the conveyor belt 7, more specifically by consecutively shooting a sleeve downward to arrange the sleeve loosely around the container 3.

The sleeves 22 are cut and shot over the containers 3 supported and conveyed (S6) in the transport direction P _T by the container conveyor unit 6. The container conveyor unit 6 transports the sleeved container 3 further in the transport direction into an apparatus 30 for orienting the sleeve relative to the sleeved container 3 and then into a heating unit 5, e.g. into a steam oven, a tunnel-shaped hot air oven and/or an irradiation unit for irradiating the sleeved containers with infrared light. In case the heating unit 5 is a steam oven steam will heat the sleeves arranged around the containers and shrink (step S7) the sleeve around the container so that they become fully attached to the container. In a subsequent step further operations can be performed, for instance a drying process.

Figure 2 shows an embodiment of the orienting unit 33 in more detail. The figure shows a top view of the movable conveyor belt 7 of the container conveyor unit 6 for transporting a container 3 in a transport direction indicated by an arrow P _T along a transportation path indicated by reference number 51. In the shown embodiment a sleeve orientation unit 33 is arranged on either side of the conveyor belt 7. In other embodiments only one sleeve orientation unit 33 is provided, arranged at one of the two sides of the conveyor belt 7, or more than two sleeve orientation units are provided. A perspective view of an embodiment of the sleeve orientation unit 33 is shown in figure 3. The unit 33 comprises a support surface in the form of a sleeve supporting conveyor belt 34 that is wound around wheels/rollers 35. One of these wheels/rollers is a driving wheel/roller 35 that drives sleeve supporting conveyor belt 34. This wheel/roller 35 is controlled by a sleeve supporting conveyor belt drive unit 36. Each sleeve orientation unit 33 further comprises a vacuum unit 37 that applies a suction force indicated by arrows 38. Both the vacuum unit 37 and the sleeve supporting conveyor belt drive units 36 are connected to a control unit 39.The latter receives input from a determining unit that is configured for determining an angular position difference between the container and the sleeve just after the sleeve has been arranged around the container. The determining unit may comprise an optical camera 40 arranged positioned upstream of the sleeve orientation units 33 for detecting a printed image of the surface of the sleeve that has been arranged around the container. Optionally a further determining unit may be provided that is configured for determining an angular position difference between the container and the sleeve after the sleeve has been oriented or repositioned by the sleeve orientation unit (s). As an example of a further determining unit an optical camera 41 may be arranged downstream of sleeve orientation units 33. This downstream camera 41 can be used to verify the result of the orientation operation performed by the sleeve orientation units 33 and/or to assist in a self -learning operation of control unit 39, as will be explained later.

The optical cameras are but an example of possible detectors. Other detecting means may equally be applied to detect an angular positon or position difference from the top, side, or bottom of the container and/or sleeve. For instance, laser scanning techniques may be used to detect a protrusion or indentation on the container by scanning the container from the side, not excluding the front or the back.

Optionally the apparatus 30 comprises a control monitor 50 that is configured to check the calculation results of the control unit 39.

The determining unit may comprise a camera 40 positioned upstream of the sleeve orienting units and configured to detect the angular position of the sleeve, preferably relative to the axis perpendicular to the conveyor belt. For instance, the optical camera may be configured to detect a sleeve orientation identification feature with which the current orientation of a sleeve may be determined. Examples of a sleeve orientation identification feature are folding lines, seams, printed images, designs, identifiable reference points and the like, or other physical structures, all suitable to determine the angular position of the sleeve. More in particular, the sleeve may comprise an identifiable first reference point, such as an area or feature in a printed image on the sleeve. The first detector may be configured to detect the angular position of the sleeve by identifying the first reference point, preferably relative to the axis perpendicular to the conveyor belt.

The angular position of the sleeve can be determined by comparing the identified first reference point to a corresponding first reference point in a first reference image, wherein the angular position associated with the first reference image and/or the first reference point in that first reference image is known. As an example, optical camera 40 may be used to record an image of the sleeve that is arranged around the container. The recorded image may be compared with a first reference image. The reference image may correspond to the image that has been printed on the sleeve. It may further correspond to a particular angular position of the sleeve. In this case, the sleeve position refers to the position of the printed image on the sleeve instead of the position of the physical sleeve itself. The reference image corresponds to a particular position of the printed image on the sleeve that is known. By comparing the reference image and recorded image, a deviation between images can be determined, for instance a shift or rotation, and from this deviation the angular position of the sleeve, e.g. the angular position of the printed image on the sleeve, may be determined. To determine the deviation, image matching techniques can be used. To this end, features or particular areas in the images can be identified. As an example, the position of a specific feature in the reference image, for instance the center region of a specific color patch, may be compared to the position of this same feature in the recorded image or vice versa. In other embodiments two or more positions of the feature in the reference image may be compared to two or more detected positions, i.e. positions in the recorded image, in order to improve the accuracy of the calculation of the deviation.

The container 3 may comprise an identifiable second reference point, such as a physical structure, for example a recess or a protrusion, wherein the camera 40 is configured to determine the angular position difference from a distance between the first and second identifiable reference points. Hence, the angular position difference can be determined from a single recorded image of both the sleeve and container. Alternatively, the angular position of the container has a known value or has been set to a known value upstream of the determining unit and sleeve orientation unit, wherein the angular position difference is determined by the determining unit or the control unit by comparing the detected angular position of the sleeve with the known value. In this case, there is no need to determine the angular position of the container as this value is known.

During operation, control unit 39 may control sleeve supporting conveyor belt drive units 36 using a plurality of control parameters based on information from the determining unit. For example, the support surfaces are configured to move at a well defined speed during the sleeve orientation. In such case, the only relevant parameters may be the speed of the support surface and/or the holding time during which the sleeve is held against this support surface. In some situations however, the speed is not constant as the support surface may accelerate or decelerate between speeds. Then, also the acceleration or deceleration constant, or the time during which the support surface changes speeds as well as the starting and ending speed may form control parameters.

Control unit 39 may be self-learning. For instance, it may use input from optical camera 41 which records a further angular position difference downstream of sleeve orientation units 33. The determination of the further angular position difference may be performed similar to the determination of the angular position difference upstream of sleeve orientation units 33. Control unit may determine a correlation, such as a lookup table, between the upstream angular position difference, the control parameters that are used to correct this difference, and the resulting downstream angular position difference. The correlation should enable control unit 39 to select the appropriate control parameters to reduce the angular position difference to acceptable levels.

The sleeve orientation unit 33 is shown in more detail in the partially taken-away view of figure 3. The sleeve orientation unit 33 comprises a perforated sleeve supporting conveyor belt 34 that is arranged in upright position (for instance a vertical position) relative to the conveyor belt 7 that is arranged in a lying position (for instance a horizontal position). The perforated sleeve supporting conveyor belt 34 is mounted around three rotatable elements, in this embodiment three wheels and/or rollers 35. At least one of the three wheels/rollers 35 can be driven by a sleeve supporting conveyor belt drive unit (not shown) , for instance an electric motor driving a rotation shaft 65 of the wheel/roller. The wheels/rollers 35 are rotatable in two opposite rotational directions 60 (clockwise and anti-clockwise) so as to move the perforated sleeve supporting conveyor belt 34 in forward direction 62 corresponding to the transport direction P _T of the conveyor belt 7 or in backward direction 63. Two of the wheels/rollers are positioned alongside the conveyor belt 7 and are aligned with the transport direction P _T of the conveyor belt 7. More specifically, figure 2 shows a straight portion 64 wherein the perforated sleeve supporting conveyor belt 34 runs parallel to the lying conveyor belt 7. This straight portion 64 is able to support the sleeve 22 along a predetermined length along the transport direction when the sleeve supporting conveyor belt 34 moves in the forward or backward direction parallel to the transport direction P _T .

The perforated sleeve supporting conveyor belt 34 is formed by a central elongated belt portion 66, an upper elongated edge portion 67 and a lower elongated edge portion 68. The perforated sleeve supporting conveyor belt 34 is engaged by each of the wheels/rollers 35 on the elongated edge portions. More specifically, the upper elongated edge portion 67 is engaged by an upper disk 69 of the wheel/roller 35 while the lower elongated edge portion 68 is engaged by a lower disk 70 of the wheel/roller 35. The central elongated belt portion 66 has been provided with a number of perforations 72, preferably evenly distributed over its surface.

The sleeve orientation unit 33 also comprises a vacuum unit 37 configured to hold a sleeve 22 against the supporting conveyor belt 34, as will be explained hereafter. The vacuum unit 37 comprises a housing 75 forming a vacuum chamber connectable via a discharge conduit 77 to a vacuum pump 76 (schematically shown in figure 1). The housing 75 has an open inlet 80 forming a suction mouth. The inlet 80 is of a generally rectangular shape in cross-section and extends parallel to the transport direction P _T of the containers. The inlet 80 of the housing 75 may be formed by an upper wall portion 81, a lower wall portion 82, a proximal wall portion 83 and a distal wall portion 84. The wall portions 81-84 form a circumferential edge around the open end of the inlet 80. The circumferential edge may be configured to contact the sleeve supporting conveyor belt transported along the suction mouth.

The height (h) of the open inlet 80, i.e. the height of the proximal and distal wall portions 83,84, may essentially correspond to the height of the central elongated belt portion 66. The inlet 80 is therefore fully covered by the central elongated belt portion 66 of the sleeve supporting conveyor belt 34. More specifically, since the perforations 72 are only present in the central elongated belt portion 66 and not in the upper or lower elongated edge portion 67,68 and additionally the inner side of the sleeve supporting conveyor belt 34 facing the inlet 80 is in contact with the circumferential edge formed by the walls 81-84 or at least in close proximity to the walls 81-84 when the belt 34 is moving along the inlet 80, the vacuum unit 37 only receives ambient air through the perforations in the central elongated belt portion 66 of the sleeve supporting conveyor belt 34, as is indicated by arrows 85. This means that the suction force that may hold a sleeve against the sleeve supporting conveyor belt 34 is applied only through the perforations that are temporarily present in front of the rectangular inlet 80 of the vacuum chamber.

Referring to figure 1. the length (1) of the open inlet 80 of the vacuum chamber, i.e. its dimension in transport direction between the proximal and distal wall parts of the inlet, in embodiments of the present disclosure, may be equal to or smaller than the distance between the first and second rotating element. In other words, the length (1) of the open inlet 80 may be selected to correspond to the length of the straight portion 64 (wherein the straight portion 64 is the area wiiere the perforated sleeve supporting conveyor belt 34 runs parallel to the lying conveyor belt 7). in this manner maximum use can be made of the available space to accomplish a suitable suction length while at the same time the transition between a suction area and a non-suction area is well defined so that the suction operation can be performed in a controlled manner.

The operation of the apparatus will now be described referring to the figures 4A-4F. The figures are top views showing a container conveyor belt 7 shown in figures 1 and 2, carrying a row of containers 3 on an imaginary transportation path in a transport direction P _T . A first and second sleeve orientation unit 90,91 are arranged at either side of the transportation path. The sleeve orientation units 90,91 comprise respective sleeve supporting conveyor belts 93,94 arranged alongside the transportation path. Each orientation unit is configured to support the sleeve along a predetermined length along the transport direction. The predetermined length corresponds to the distance between proximal wall part 95 and distal wall part 96 of the inlet 103 of the sleeve orientation unit 90,91. In the figures the direction of movement of a sleeve supporting conveyor belt 93,94 is indicated by arrows 99,100, as will be explained later. Furthermore, arrows 97,98 show that the suction force created by each of the vacuum units is laterally outwards and in opposite directions. The figures also show that each of the containers 3 has a sleeve 22 (loosely) arranged around an outer surface thereof. A sleeve has been provided with two different markers, marker A and marker B.

In figure 4A the start position is presented wherein a container 3' has been transported by the container conveyor belt 7 to a position wherein the sleeve first attaches to the sleeve supporting conveyor belts 93,94 when the center of the container 3' is aligned between the proximal wall part (left end in the figure) of the straight surface of both sleeve supporting conveyor belts 93, 94. The sleeve supporting conveyor belt 93 is moved in a counter-clockwise direction 99 while the sleeve supporting conveyor belt 94 is moved in a clockwise direction 100. The speed of the movement of the straight parts of each of the sleeve supporting conveyor belts 93, 94 may be selected to correspond to the speed of the container conveyor belt 7.

In a later moment in time (as shown in figure 4B) the container has traveled over a distance in the transport direction. The direction of movement of the sleeve conveyor belt 93 is caused to reverse while the direction of movement of the other sleeve conveyor belt 94 is maintained. In this case the orientation of the sleeve 22 is caused to move, i.e. to rotate around an imaginary axis perpendicular to the upper surface of the container conveyor belt 7, as can be derived from the shifted positions of the respective markers A and B. When rotating the sleeve relative to the container 3, the rotational position of the container 3 itself is not changed. The rotating of the sleeve 22 relative to the container is continued (figures 4C-4E) unit the markers A and B have reached a suitable position (for instance rotated over 180 degrees with respect to their original orientation, in other examples the rotation may be over any angle). The sleeve 22 in its end position is finally released from the container 3' when the center of the container 3' is aligned between the distal wall portion (right end) 96 the straight surface of the supporting conveyor belts, as is shown in figures 4E/4F.

As mentioned earlier, the suction forth is essentially constant and applied continuously, and only through the perforations 72 of the sleeve supporting conveyor belt 93, 94, which makes the direction of the suc tion force to be perpendicular to the transport direction P _T of the container. This means that the period of the sleeve attached to the sleeve supporting conveyor belt 93, 94 is determined easily and the orientation is accurately controlled. Furthermore, each sleeve supporting conveyor belt 93, 94 can be moved in the same or opposite direction which enables a faster completion of the sleeve orientation.

Figure 5 shows a further embodiment of an apparatus 1 12. The apparatus 1 12 not only comprises a container conveyor unit 6 including a (first) container conveyor having a first moveable conveyor belt 7 arranged for carrying the bottom end of one or more containers 1 13 for transporting the container in a transport direction, but also a second container conveyor 1 15 having a second moveable conveyor belt 117 placed above the first container conveyor and arranged so as to hold the upper end of the container 1 13. The figure also shows a conveyor drive 116 for driving the second conveyor. The conveyor drive of the lower conveyor and the conveyor drive of the upper conveyor can be controlled to cause the container conveyor belts 7,117 to move

synchronously, i.e. at essentially the same speed.

Thus a separate upper container conveyor belt 1 17 which is synchronized with the lower container conveyor belt is provided. The upper container conveyor belt 117 may hold the top (lid or cap) of the container while being conveyed. The height between the lower and upper container conveyor belt may be a fixed height. However, in other embodiments the height may be adjustable, for instance adjustable to the height of the specific container being conveyed. In this manner one can hold the top of the container in order to prevent the container from rotating while the label is rotated by the sleeve supporting conveyor belt.

This arrangement is typically suitable for lightweight containers, relatively thin sleeves or sleeves of which the inner circumference is closer to the outer circumference of the container. Figures 6 and 7 show a further embodiment of an apparatus. The apparatus corresponds to the apparatus 30 described in connection with figures 2 and 3 and a detailed description of corresponding parts and functions will be dispensed with. The apparatus of figures 6 and 7 differs in that the container conveyor unit 6 comprises a container conveyor belt 120 that is provided with an array of perforations 121 extending in transport direction along the center line of the belt. The apparatus also comprises a first and second sleeve orientation unit 90,91. A further distinguishing feature is that the apparatus comprises a vacuum system for providing a downward suction force through the perforations 121 in order to hold the bottom ends of the containers 1 13 more firmly against the upper surface of the container conveyor belt 120. The suction force may reduce the risk of movement of the container relative to the moving container conveyor belt 120 during the sleeve orienting operation of the sleeve orientation units 90,91. The vacuum system may comprise a vacuum element 122, arranged below the perforations in the moveable perforated conveyor belt, a vacuum duct 123 connected to a vacuum hose 124 and a vacuum pump (not shown) connected to the vacuum hose 124. The vacuum element may be a stationary box extending from a position upstream of the sleeve orientation units to a position downstream of the sleeve orientation units and positioned right below the bottom surface of the container conveyor belt and the perforations provided therein.

The vacuum pump creates a vacuum (low pressure) by inducing an air flow (direction 126, figure 7). The vacuum pump creates an downward suction force (indicated by 128 in figure 8). The vacuum pump can be the vacuum pump of the vacuum unit 37 or a separate vacuum pump.

In figure 6 the sleeve 1 14 (cf. figure 7) that is arranged around the container 113 and is held against the outer surface of the sleeve supporting conveyor belt 93,94 is not shown in order to reduce the complexity of the drawing. In reality this (very thin) sleeve 1 14 is present and extends in either gap 125 (or both gaps 125) between the outer surface of the sleeve supporting conveyor belt 93,94 and the outer surface of the container 1 13.

In situations wherein the present apparatus 30 for orienting sleeves with respect to containers transported on a container conveyor 7 is used to orient sleeves that are to be arranged at a position between the top and bottom of the containers (in other words, wherein the sleeves are partial labels wherein the bottom edge of the sleeve extends at a higher position than the bottom of the container, for instance when a sleeve is arranged in the middle of the container), measures should be taken to prevent the sleeve from sliding further downward once the sleeve has been arranged and properly positioned around the container. Conventionally water spray devices are used to temporarily fix a label to a container by wetting the outer surface of the container before a sleeve is applied so as to ensure that a sleeve moving downward (or upward) along the container outer surface sticks to the container surface at a suitable position (i.e. at the right height, for instance on the middle) and remains in that position. Therefore, by spraying water on the lower part of a container prior to the sleeve arriving at the sleeve application device (for instance, the sleeve labelling device 2), the sleeve (once the sleeve has arrived at the sleeve application device and a sleeve is moved onto the container) would go down on the upper part of the outer surface of the container to which upper part no water has been applied, but would not go down any further from a certain height position where the lower part of the container starts (i.e. where water has been applied on beforehand to the container surface).

However, once a sleeve has been arranged around the container in this manner, it cannot be easily moved on the wet outer surface of the container because of the resistance of the water. This means that the orientation of the sleeve by the apparatus 30 as described herein which implies a rotation of the tubular sleeve around the container may be impeded. Additionally, if the transport distance along the container conveyor 7 between the water spray device and the sleeve application device is long, the wet lower part of the container outer surface can at least partially be dried again, so that there is a risk that the sleeve cannot be held long enough at the correct position.

According to embodiments of the present disclosure, water is therefore sprayed onto the outer surface of the container and/or the inner surface of the sleeve after the sleeve has been applied to the container and the sleeve has come to be gripped and oriented by the one or more sleeve supporting belts 93,94 of the sleeve orientation unit 33. The sprayed water ensures that the oriented sleeve adheres to the container's outer surface and therefore stays in position until the sleeve is finally attached to the container by heat-shrinking the sleeve in the heating unit.

Figures 8A-8C, 9 show an embodiment of a water spray device for applying water droplets to a tubular sleeve that is to be attached at a certain height on the container 3 (i.e. a height hi from the bottom of the container 3 until the lower edge 140 of the sleeve 22, figure 8A). Once the sleeve 22 has been arranged (for instance in the downward direction 19, see figure 9) around the container 3 by the sleeving (labelling) device 2 (figure 9), the sleeve 22 is kept at the right height relative to the bottom of the container 3, i.e. relative to the upper support surface of the conveyor 7 on which the container 3 is placed, while the container 3 is travelling towards the sleeve orienting apparatus 30 by using one or more stationary support elements 141 (figure 9) arranged sideways along the length of the container conveyor 7. The one or more support elements 141 extend parallel to the support surface of the container conveyor 7. When the sleeved container is transported on the container conveyor 7 the sleeve 22 is supported on its lower edge 140 so that the sleeve 22 is carried at a suitable height h _t with respect to the container 3.

When the sleeved container arrives at the orientation unit(s) 33, the sleeve 22 is gripped by the sleeve supporting belts 93, 94 and then rotated (if needed) to adjust the rotational position of the sleeve 22 relative to the container 3. In figures 8A and 8B is shown that the sleeve supporting belts 93, 94 of the orientation unit 33, at least the lower edge 140 thereof , is gripped on two sides by the sleeve supporting belts 93,94. Individual movement of the sleeve supporting belts 93,94 causes the sleeve 22 to be rotated to the desired rotational position relative to the container 3.

Once the sleeve 22 of the sleeved container 3 has been rotated to a suitable end position, the sleeve 22 should be temporarily attached to the container 3 to avoid the sleeve 22 to become ill- oriented when traveling from the orienting apparatus 30 towards the heating unit 5 for heat- shrinking the sleeve 22 onto the container 3.

The temporary attachment could be accomplished by using a preheater that partially shrinks the sleeve 22 (not completely) to determine the position of the sleeve 22 relative to a container 3. With such preheater used, the finished appearance of a shrunk sleeve may be not sufficiently good. The temporary attachment of the sleeve 22 to the container 3 could alternatively be accomplished by a water spray device 130 spraying water onto the container 3 in such a manner that water is provided at a position between the inner surface of the sleeve 22 and the outer surface of the container 3, thereby more or less attaching the sleeve 22 to the outer surface of the container 3. With using the water spray device 130 instead of a preheater for determining the position, the finished appearance of the sleeved container will be relatively good because a sleeve 22 is shrunk completely by a one time heating.

In the embodiment shown in figures 8A-8C and figure 9, the apparatus 30 comprises a water spray device 130 arranged above the orientation units 33. The water spray device 130 comprises a water connection 131 for the supply of water, a pump 132 for pumping the supplied water to one or more spraying nozzles 133 ',133 ² towards a sleeved container (i.e. a container that already has been provided with a sleeve). The number of spraying nozzles may vary: in some situations a single spraying nozzle may be sufficient to arranged water in the right quantity at the right position to allow the sleeve to temporarily adhere to the container outer surface, while in other embodiments the number of spraying nozzles is three or even more. The larger the number of spraying nozzles, the more evenly the water may be distributed over the container outer surface and the smaller the risk of the sleeve inadvertently moving at the part where water is not applied. With more than two or more than three spraying nozzles distributed at equidistant positions relative to the perimeter of the container, the sleeve 22 may be kept more even and in relatively good balance (i.e. preferably horizontally).

The water should be positioned in the interspace 137 (figure 8C) between the inner surface of the sleeve 22 and the outer surface 139 of the container 3. The amount of water may be relatively small, one or more drops of water can be sufficient to hold the sleeve 22 in place as it travels towards the heating unit 5, even if the distance between the sleeve orientation apparatus 30 / water spraying device 130 and the heating unit 5 is long and/or the transport speed of the container 3 on the container conveyor 7 is high. It is noted that the water spraying device 130 is particularly useful in situations wherein the sleeve 22 applied on the container outer surface is to be arranged at a certain height above the bottom of the container 3. However, also in situations wherein the sleeve 22 extends to the bottom of the container 3 and can rest on the support surface of the container conveyor 7 the water spraying device 130 may be used, for instance to reduce the likelihood of movement (especially rotation) of the sleeve 22 after it has been accurately oriented with respect to the container 3 and is on his way to the heating unit 5.

Furthermore, in the embodiment shown in figure 9 water is applied to the upper end of the container 3 at an interspace 137 between the sleeve 22 and the container 3. This arrangement has particularly advantageous since the water droplets flow downwards due to the gravity.

Alternatively or additionally, the water may be sprayed to the lower end of the container 3 so as to adhere the bottom edge 140 of the sleeve 22 to the container 3.

In operation, the sleeving (labelling) device first applies a sleeve 22 around a container 3 transported on the container conveyor 7. The sleeved container is transported to the orientation apparatus 30 while the lower or bottom edge 140 of the sleeve 22 is supported on the support elements 141. The sleeve orienting apparatus 30 then correctly orients the sleeve 22 relative the container outer surface by rotating the sleeve 22 relative to the container 3 (which container 3 remains in a fixed rotational position during transport thereof from the sleeving (labelling) device 2 to the heating unit 5. Directly after the orientation by the orientation unit(s) 33 of the apparatus 30, the spraying nozzle 133 of the water spray device 130 sprays water towards the sleeve 22 and the container 3, more specifically in a direction generally parallel to the axial direction of the container 3 and into the interspace 137 between the inner surface of the sleeve 22 and the outer surface of the container 3. This causes the oriented sleeve to get (temporarily) attached to the container 3.

Preferably the water is sprayed while the sleeve 22 is still contacted and held by the one or more sleeve supporting conveyor belts 34,93,94 of the one or more sleeve orienting units 33. In this case the water spray device 130 is arranged right above or below the one or more orienting units 33 and the water is sprayed downward or upward directly on the container 3 while the sleeve 22 is held by the sleeve supporting belt(s) 93,94. In other embodiments, however, the water spray device 130 is positioned downstream of the orienting unit(s) 33 of the orienting apparatus 30 so that water is applied to the sleeved container while the sleeve 22 is no longer held by the sleeve supporting bell(s) 93, 94. In these embodiments the water spray device 130 is preferably located close to the orienting unit(s) 33 so as to minimize the risk of the correctly oriented sleeve 22 to become incorrectly oriented, for instance under the influence of gravity.

The container conveyor 7 as described herein may be configured to transport the containers 3 in a circumferentially fixed position along the transportation path. Additionally, consecutive containers 3 on the container conveyor 7 may be mutually aligned so that they all have the same orientation relative to the container conveyor 7. Therefore, the containers 3 may remain circumferentially aligned in the same orientation while being transported towards the heating unit 5. In other words, the rotational orientation of the containers 3 remains the same during the transport of the container 3 along the sleeving device 2, the sleeve orientation apparatus 30, water spray device 130 (if present) and the heating unit 5.

In case the containers 3 are shaped to have an oval or polygonal cross-section, each container 3 can be relatively easily arranged in a fixed circumferential orientation (i.e. an orientation relative to the container conveyor 7 that essentially does not change during transport of the container 3 along the transportation path) or even in a fixed circumferentially aligned orientation (i.e. an orientation wherein consecutive containers 3 on the container conveyor 7 are arranged in a fixed and circumferentially aligned orientation relative to each of the other containers), for instance by making use of one or more conveyor guides. In an embodiment (not shown in the figures) the conveyor guides extend parallel to each other and have an mutual distance that is only slightly larger than the smallest diameter of the container (but smaller than the largest diameter) so that a container transported on the container conveyor 7 and guided between the container guides are guided to align in one direction. To this end, a conventional screw guide can be used as conveyor guide to arrange the containers 3 in a fixed circumferential orientation. In case of some differently shaped containers, for instance containers with a round (circular) cross- section (herein also referred to as a "round container"), containers including the cap with an external feature, it tends to be more difficult to circumferentially position or even align the containers with this type of conveyor guide. It may be needed to determine technical means that are able to properly align containers 3 having a circular cross-section, especially in cases wherein the round container is provided with an external feature, such as a hinge cap and the like.

The external feature needs to be oriented properly and accurately so that a (main) design of a sleeve 22 to arranged on the round container 3 can be accurately aligned with the external feature (for instance, properly arranged on both sides of a flange tab of the hinge cap). This type of "round" containers wherein the sleeve on the outer surface is to be aligned to a cap having a hinge tends to be used more and more in the food industry. The inventors came to the insight to use such external feature as a container orientation identification feature that can be employed to orientate a container, as will be explained hereafter.

One option for orientating a round container would be to rotate the round container itself while being transported on the container conveyor in order to properly orient the external feature (eg. the hinge cap). After the external feature has been properly oriented, a sleeve orientation according to the method and apparatus as described herein may be applied in order to properly orient the sleeve relative to the round container. A round container may be rotated to orient a hinge cap of the round container in the same direction in various ways (as for instance is described in the document NL 2013723 A):

1. Rotating a container on a table: a container on a table is rotated by rotating the table in dependence of an angular position difference between a cap image which is detected with a camera and the reference image which is registered beforehand.

2. Rotating a container with holding the cap part: a cap part of a container is held with a belt and the container is rotated by driving the belt in dependence of an angular position difference.

3. Rotating a container with holding the body part: a body part of a container is held with a belt and the container is rotated by driving the belt in dependence of an angular position difference.

A disadvantage of any of the above may be that the technical means (i.e. a container orientation apparatus) for rotating the container tend to be complex and relatively expensive, the adjustment of the technical means may be difficult because they are complicated for an operator as well, and the technical means may require many kinds of a support units, depending on the diameter of the containers (which may vary considerably). Furthermore, there is a concern in the ways mentioned above that the container may rotate during transportation between the container orientation apparatus and the sleeve orientation apparatus on the container conveyor.

More generally, it appears that orienting a lightweight object such as a sleeve is easier than orienting a heavy object such as a (filled or empty) container in terms of (at least) complexity of the technical means needed and their energy consumption. In addition, sleeve orientation tends to be more accurate than container orientation because of the weight of the object to be oriented.

In embodiments of the present disclosure therefore each container remains arranged in a fixed circumferential orientation or even in a fixed, circumferentially aligned orientation (instead of rotating the container) . In addition to the sleeve orientation action performed by the one or more sleeve orientation units based on a detected original sleeve orientation, also the orientation of the container is detected. The sleeve orientation then is not only based on the detected original sleeve orientation, but also on the detected original container orientation.

Referring to figures lOA-l OC and 1 1 , in embodiments of the present disclosure, the determining unit may comprise a detection unit 138 configured to detect the angular position of the container and to detect the angular position of the sleeve 22. More specifically the detection unit 138 may be configured to detect the angular position of a container orientation identification feature 143, 144 of the container 3 and to detect the angular position of a sleeve orientation identification feature 155 of the sleeve 22. The determining unit 138 may further comprise a distance calculating unit 151 configured to calculate the distance over which the sleeve 22 is to be rotated to correctly orientate the sleeve 22 relative to the container 3, based on the detected angular positions of the container 3 and the sleeve 22. In a preferred embodiment the calculating unit 151 is also configured to determine the rotational direction in which the sleeve 22 is to be rotated so that the minimum distance can be selected. The distance calculating unit 151 may be a part of the earlier defined control unit 39 or could be embodied as a separate unit.

The determining unit may further comprise a control unit (for instance the control unit 39 (cf. figure 2) and/or an additional control unit). The control unit 39 is configured to control the at least one orientation unit to rotate the sleeve 22 over the determined distance. In case the calculating unit 151 has determined the preferred rotational direction, the control unit 39 may cause movement of the sleeve support belt(s) in a suitable direction to cause the sleeve 22 to rotate in the preferred direction.

The detection unit 138 may comprise a first detector, for instance a first camera 150, wherein the first detector is arranged to detect the angular position of the (container orientation identification feature of the) container 3, and a second detector, for instance the (first) camera 40 shown in figure 2, wherein the second detector is arranged to detect the angular position of the sleeve 22. More specifically, referring to figures lOA-lOC, the first camera 150 may be arranged to capture an image of the sleeved container from a position above or below the container 3. The second camera 40 may be camera arranged at a position sideways of the sleeved container.

Additionally or alternatively, at least one of the detectors may be a mechanical position sensor configured to sense the orientation of the container orientation identification feature.

As shown in figures l OA-l OC the orientation of the sleeve 22 arriving at the orientation apparatus 30 may be determined from the position of a sleeve orientation identification feature 155 such as a predefined reference symbol, a special design or printed image on the sleeve 22, a folding line, seam or other physical structure enabling the determination of the angular position of the sleeve. The orientation of the container 3 may be determined from the position of a container orientation identification feature 143,144 of the container 3. The container orientation

identification feature is formed in this embodiment by a hinge part 143 provided at one lateral side of the cap 142 and a gripping tab 144 provided at an opposite lateral side of the cap 142 (cf. figure 10B).

In operation, a sleeve 22 is arranged around the container 3 using the sleeving device 2 as discussed earlier. After the sleeving device 2 has applied the sleeve 22 around a container 3 and the sleeved container 3 has travelled in the direction of the orientation unit 33, the detection unit 138 of the determining unit detects the angular position of the container 3 by using the camera 150 placed above the container 3 and the angular position of the sleeve 22 by using the camera 40 placed to the side of the container 3. The distance calculating unit 151 calculates the distance the sleeve 22 has to move over the container outer surface (and thereby the distance the sleeve supporting belt(s) has/have to be moved) to properly orientate the sleeve 22 relative to the container 3. The distance calculating unit 151 also calculates the rotational direction in which the sleeve 22 is to be rotated to correctly orientate the sleeve 22 relative to the container 3. In this way the distance may be minimized and the orientation speed (i.e. the speed at which the orientation unit(s) 33 may orientate a sleeve 22 relative to a container 3) may be increased.

Referring to figures 10B and I OC, on basis of the image captured by the camera 150 showing a top view of the sleeved container 3 and a reference image 156 showing a pair of orthogonal reference lines 151, 152, an imaginary straight line 153 is drawn extending through the center 153 of (the cap 142 of) the container 3 and the at least one of the container orientation identification features 143,144. The calculating unit then determines the angle (a) between the first reference line 151 and the imaginary straight line 153. A first distance (dj) is determined from angle (a) and container circumference information about the circumference or perimeter of the container 3. The latter information may be the diameter of the container 3 in case of a container 3 having a circular cross-section or similar information representative of the shape and outer dimensions of the container 3. In case of containers 3 with a different cross-section, such as an oval or polygonal cross-section, a conversion may be needed to calculate the position difference. The container circumference information may have been pre-stored in the apparatus 30, for instance in the distance determining unit or in a separate storage, and/or may be detected, for instance based on one or more images of the container made by a camera.

For example, when the angle (a) is 140 degrees and the diameter of the container is 66 mm, then the first distance (di) (in mm) is d = 3,14 * 66 * (-140 /360) = -81 mm (wherein the sign of the angle or the sign of the resulting distance denotes the rotation direction).

Similarly, on basis of the image captured by camera 40, a second distance (d ₂ ) 161 between the reference line 151 and a line 157 extending parallel to reference line 151 and through the sleeve orientation identification feature 155 is determined. This distance may be determined directly from the image. In the above example the second distance (d ₂ ) may be -7 mm. The total distance (d) over which the sleeve 22 must be rotated then corresponds to the summation of the first distance (dj) and second distance (d ₂ ). In the example the total distance d would be (-81 - (-7) =) -74 mm.

In order to avoid misorientation of a once oriented sleeve, the sleeve orientation apparatus 30 can be located right before the heating unit 5 and/or (a small amount of) heat can be applied in a preheating phase to a part of the sleeve if the transport distance between the orientation unit and a tunnel is long. Additionally or alternatively, the embodiments of the container orientation identification unit according to figures 10A-10C,1 1 may be combined with the embodiments of the water spraying units according to figures 8A-8C, 8 so that the risk of a once aligned sleeve 22 becoming misorientated is reduced.

It is to be understood that this invention is not limited to particular aspects described, and, as such, may vary. It is also to be understood that the terminology used herein is for the purpose of describing particular aspects only, and is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims.