Abstract:
A method for producing a container package includes forming container streams in which the containers have had adhesive applied thereto, separating the containers into container groups, with a container from each stream being in the group, and pressing the containers together from the side by using a pair of clamps so that the adhesive binds the containers together to form the container package.

Description:
RELATED APPLICATIONS 
       [0001]    This is the national stage, under 35 USC 371, of PCT application PCT/EP2014/067709, filed on Aug. 20, 2014, which claims the benefit of the Aug. 28, 2013 priority date of German application DE 102013109305.1, the contents of which are herein incorporated by reference. 
     
    
     FIELD OF INVENTION 
       [0002]    The invention relates to packaging, and in particular, to forming container groups. 
       BACKGROUND 
       [0003]    Containers are often sold in units that include multiple containers. These containers must be held together in some way. 
         [0004]    A known way to hold containers together is by using an adhesive. In order to form such units, it is necessary to compress containers against each other to promote adhesive bonding. 
       SUMMARY 
       [0005]    In one aspect, the invention features a method for producing a container package. Such a method includes receiving a first and second lanes of streaming containers at a container inlet of a packaging device, and applying adhesive to the containers at corresponding first and second treatment sections. This is followed by placing containers from the two treatment sections onto a transport section to form two lanes of containers. Once on the transport section, the containers are separated into container groups, each of which includes a container from each of the two lanes. This occurs as the containers move along the transport direction on the transport section. Additionally, the containers are pressed together, or compressed, so that the adhesive that was applied to the containers at the first and second treatment stations binds the containers in the container group to form a container package. The act of separating the containers is carried out by using first and second clamp heads that face each other across the transport section. These clamp heads move together along the transport section. The act of compressing, or pressing, the containers together includes pressing a container in one lane using the first clamp head and pressing the container in another lane using the second clamp head. 
         [0006]    In some practices, each treatment section comprises a container inlet. In these practices, the method further includes, at each of the container inlets, receiving a container stream. 
         [0007]    Other practices of the method include combining the first clamp head with at least one other clamp head to form a first clamp unit, and combining the second clamp head with at least one other clamp head to form a second clamp unit. In this practice, all clamp heads in a particular clamp unit move together. Among the practices of the invention are those in which forming the clamp units includes forming clamp units that each consist of three clamp heads. 
         [0008]    In other practices of the invention, each container has a container axis that defines a radial direction. In these practices, compressing includes causing the clamp heads to press along radial directions of their respective containers. 
         [0009]    Other practices of the invention include causing the first and second clamp heads to follow corresponding first and second peripheral loops, each of which has an inner path section that extends along a corresponding side of the transport section. Among these practices are those in which causing either one of the clamp heads to follow a peripheral loop includes causing it to follow a first guide rail. 
         [0010]    Practices of the invention also include moving the clamp heads using a mechanical drive, moving them using an electrical linear drive, and individually controlling the motions of the clamp heads so that different clamp heads can move at different speeds. 
         [0011]    In another aspect, the invention features an apparatus for forming a container package. Such an apparatus includes a container inlet that has been configured for receiving a two-lane container stream, and first and second treatment sections that receive each lane. Each treatment section has adhesive applicators for applying adhesive to a container. A transport section following the first and second treatment sections conveys another two-lane container stream along a transport direction. Moving along this transport section, also in the transport direction, are clamp heads. These clamp heads cooperate to separate containers moving along the transport direction into container groups. Each clamp head has a container holder configured to grip a container on a surface thereof. The clamp heads are organized in pairs so that first and second clamp heads of a pair are disposed to move together along the transport section opposite each other. The first and second clamp heads of a pair cooperate to compress containers in a container group together so that adhesive applied to the containers binds the containers together to form the container package. 
         [0012]    Some embodiments include clamp units, each of which has two or more clamp heads. In these embodiments, the first and second clamp heads are constituents of corresponding first and second clamp units that face each other across the transport section. These two clamp units, and hence their constituent clamp heads, move along the transport direction together. Among these embodiments are those in which each clamp unit has no more than three clamp heads. Also among these embodiments are those in which the first clamp head interacts with a chain that forms a mechanical drive for moving the first clamp unit. 
         [0013]    Other embodiments include closed paths on either side of the transport section, each of which has an inner section that extends along the transport section. In these embodiments, clamp heads move along respective closed paths. 
         [0014]    Some embodiments have a mechanical drive to move the clamp heads. A typical mechanical drive includes a belt and a cog wheel. In these embodiments, clamp heads being driven by the mechanical drive interact with a cog wheel when the clamp heads traverse a diversion section of a path. In particular, prior to entering the diversion section, a clamp head moves in a first direction. After having left the diversion section, the clamp head moves in a second direction that is different from the first direction. 
         [0015]    Other embodiments have an electric linear drive in which the clamp heads are armatures. 
         [0016]    In some embodiments, the first clamp head has a headpiece and either a trolley or a carriage that is guided on a guide rail. In these embodiments, the head piece forms a container holder and is configured to be slid in a controlled manner and guided on the carriage or trolley for executing a delivery and clamping movement. The headpiece defines a format part that is exchangeable with other format parts for accommodating at least one of different containers and different forms of container groups. Among these embodiments are those having a cam configured to control the delivery and clamping movement. In these embodiments a pilot pin is attached to the headpiece, and wherein the pilot pin engages the cam. 
         [0017]    As used herein, “contact adhesive” means an adhesive that is self-adhesive and that produces an adhesive connection by pressing. A contact adhesive is sometimes called a self-bonder. 
         [0018]    Further developments, advantages, and application possibilities of the invention are also derived from the following description of exemplary embodiments and from the figures. Moreover, all characteristics described and/or illustrated individually or in any combination are basically the subject of the invention, regardless of their inclusion in the claims or reference to them. The content of the claims is also an integral part of the description. 
         [0019]    As used herein, expressions such as “substantially” or “approximately” refer to deviations from a exact value of ±10%, preferably ±5% and/or deviations in the form of changes that are not significant for function. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]    These and other features of the invention will be apparent from the following detailed description and the accompanying figures, in which: 
           [0021]      FIG. 1  shows a package comprising multiple containers connected contact adhesive; 
           [0022]      FIG. 2  shows a device for producing the packages shown in  FIG. 1 ; 
           [0023]      FIG. 3  is a top view of multiple clamp heads of the device in  FIG. 2  that are moved along a transport section with the containers; 
           [0024]      FIGS. 4-6  show different views of a clamp unit made of three clamp heads. 
       
    
    
     DETAILED DESCRIPTION 
       [0025]      FIG. 1  shows containers  1  that have been filled and sealed. In the illustrated embodiment, the containers  1  are bottles, and in particular, bottles that have been blow-molded from a plastic, such as PET (polyethylene terephthalate). 
         [0026]    Also shown in  FIG. 1  is a container group  3 . 1  made from multiple containers. The illustrated container group  3 . 1  has six containers  1  that have been arranged in two rows of three containers  1  that lie against each other. Adhesive spots  2  connect the containers  1  to form a package  3 . The adhesive spots  2 , which are typically contact adhesive, are applied to those regions of the container&#39;s surface that touch other containers  1  in the compressed container group  3 . 1 . 
         [0027]      FIG. 2  shows a packaging device  4  that produces the packages  3  from the containers  1 . The packaging device  4  receives first and second container streams  5 . 1 ,  5 . 2  of containers  1  that have been fed standing upright to a container inlet  4 . 1  thereof. The containers  1  are tightly pressed against each other in a first transport direction A. 
         [0028]    A first treatment station  6 . 1  receives containers from the first container stream  5 . 1  and a second treatment section  6 . 2  receives containers from the second container stream  5 . 2 . In the illustrated embodiment, the first and second treatment sections  6 . 1 ,  6 . 2  are identical but disposed to have mirror-symmetry about a vertical central plane. Each treatment section  6 . 1 ,  6 . 2  includes an inlet star  7 , a treatment star  8 , and an outlet star  9 , all of which rotate about a vertical axis and have container holders around circumferences thereof. 
         [0029]    Each treatment section  6 . 1 ,  6 . 2  also includes application heads  10  for applying adhesive spots  2 . The application heads  10  are adjacent to and do not move with the treatment star  8 . Some containers require multiple adhesive spots  2 . To achieve this, there can be multiple application heads  10  separated from each other along the treatment star&#39;s direction of rotation. 
         [0030]    The container holders on the treatment star  8  permit controlled pivoting or rotation of a container  1  about a vertical container axis thereof. This controlled motion enables an application head  10  to apply an adhesive spot  2  to the correct position on the container&#39;s surface. 
         [0031]    Once adhesive spots have been applied to a container at the treatment star, the transport star  9  places the container, with its adhesive spots  2 , on a transport section  11 . The transport section  11  transports two lanes of containers  1 , one from each of the two treatment sections  6 . 1 ,  6 . 2 , along a second transport direction B. In the illustrated embodiment, the second transport direction B is the same as the first transport direction A. 
         [0032]    In the illustrated embodiment, containers  1  from the first treatment section  6 . 1  form a first lane and containers  1  from the second treatment section  6 . 2  form a second lane on the transport section  11 . The container group  3 . 1  described in connection with  FIG. 1  is formed on the transport section  11  with its rows extending along the second transport direction B. Each container group  3 . 1  is spaced apart from its neighboring container groups in the second transport direction B. 
         [0033]    Referring now to  FIG. 3 , first and second clamp units  13  lie adjacent to the transport section  11  on opposite sides thereof. Each clamp unit  13  has a number of clamp heads  12  that is equal to the number of containers in a row. As a container group  3 . 1  travels along the transport section  11 , the clamp heads  12  compress the container group  3 . 1  along both the second transport direction B and perpendicular to the second transport direction B. This ensures that the adhesive spots  2  bond containers  1  to each other. 
         [0034]    Referring now to  FIG. 2 , each clamp unit  13  moves on a corresponding first and second peripheral loop  14 . 1 ,  14 . 2 . Each of the first and second peripheral loops  14 . 1 ,  14 . 2  extends along the side of the transport section  11 . The first peripheral loop  14 . 1  has an inner path  14 . 1 . 1  and an outer path  14 . 1 . 2  separated by a diversion regions defined by cog wheels  31 . Similarly, the second peripheral loop  14 . 2  has an inner path  14 . 2 . 1  and an outer path  14 . 2 . 2  separated by diversion regions defined by cog wheels  31 . 
         [0035]    As a clamp unit  13  moves along the first peripheral loop  14 . 1  another clamp unit directly opposite also moves along the second peripheral loop  14 . 2 . The two clamp units  13  move in synchrony. 
         [0036]    Referring now to  FIG. 6 , a typical clamp head  12  includes a carriage  15  having guide rollers  16  on an underside thereof. A guide rail  17  guides the carriage  15 . The course of the guide rail  17  corresponds to the first and second peripheral loops  14 . 1 ,  14 . 2 . 
         [0037]    The carriage  15  carries a strip-like headpiece  19  that moves horizontally in a clamping direction C that is perpendicular to the second transport direction B. In the illustrated embodiment, the headpiece  19  protrudes over a side of the clamp head  12  or of the carriage  15  turned towards the transport section  11 . 
         [0038]    The headpiece  19  includes two container holders  20  that are adapted to the diameter of the containers  1 . These container holders  20  are spaced apart from each other in the vertical direction so that they can hold a container  1  over part of its circumference at two vertically separated regions of the container  1 . In the illustrated embodiment, the container holders  20  hold the container  1  over less than half of its circumference. 
         [0039]    Two parallel guide rods  21  extend from a rear surface of the headpiece  19 . These guide rods  21  cause the headpiece  19  to engage in a delivery and clamping movement in the clamping direction C. Each guide rod  21  has one secured end. A pair of corresponding guides  22  on the carriage  15  guides the motion of the guide rods  21 . 
         [0040]    The headpiece  19 , together with its container holders  20  and guide rods  21 , forms a modular format part  18  that can be swapped out for another format part  18  when the packaging device  4  is switched over to process different kinds of containers  1  with a different container diameter and/or shapes. 
         [0041]    First and second pilot pins  23 ,  24 , best seen in  FIG. 5 , facilitate controlled delivery and movement of a clamp head  12  in the clamping direction C. These first and second pilot pins  23 ,  24  protrude downwards, with the first pilot pin  23  protruding further than the second pilot pin  24 . 
         [0042]    As the clamp unit  13  moves along the inner path  14 . 1 . 1 ,  14 . 2 . 1 , it engages a guide cam  25 . The course of each guide cam  25  is selected such that, before containers have been transferred from the transport star  9  to the transport section  11 , the headpieces  19  are initially outside the transport section  11  or the movement path of the containers  1 . As the clamp unit  13  proceeds along the inner path  14 . 1 . 1 ,  14 . 2 . 1 , the guide cam  25  gradually moves the clamp units  13  toward the transport section  11 . In the end, all containers  1  forming a particular container group  3 . 1  are between two clamp units  13  lying on opposite sides of the transport section  11 , and in particular, between the clamp heads  12  or the headpieces  19  thereof. This permits the containers  1  in a container group  3 . 1  to be gripped and pressed against each other. 
         [0043]    In some cases, the containers  1  are elastically deformable, at least within limits. Examples of such containers include those made of plastic. When such containers are used, a slight deformation of one or more containers occurs when clamp heads  22  clamp against the containers  1 . This causes a reciprocal clamping of those containers in the container group  3 . 1  that are next to each other in the second transport direction B. As a result, it is possible to promote a reliable adhesive connection between containers  1  that are next to each other along the second transport direction B. 
         [0044]    In some embodiments, a similar effect can be achieved by arranging the guides  22 , and in particular the guides on the two outer clamp heads  12  of each clamp unit  13 , such that the clamp heads  12  move along a direction that has a component both in the clamping direction C and in the second transport direction B. 
         [0045]    As the clamp units  13  move further along the inner path  14 . 1 . 1 ,  14 . 2 . 1  after having compressed the containers in the container group  13 . 1 , the distance between the guide cams  25  and the transport section  11  increases. As a result, the guide cams  25  on either side of the transport section  11  cause the clamp units  13  on either side of the transport section  11  to veer outward away from each other. This causes the headpieces  19  to release the containers. 
         [0046]    When forming container groups  3 . 1  from containers  1  provided by the transport stars  9 , a clamp head  12  or a headpiece  19  thereof engages a container  1  as it comes off a transport star  9  and carries that container along the second transport direction B. It does so at a speed that is slightly greater than the transport speed at which the containers  1  are fed to the transport section  11 . This spaces container groups  3 . 1  from each other along the second transport direction B. 
         [0047]    Two clamp units  13  arranged opposite each other on the two sides of the transport section  11  compress the containers  1  against each other to form container groups  3 . 1 . Pairs of clamp heads  12  from these clamp units  13  face each other across the second transport direction B. 
         [0048]    A friction material  26  on the container-contact surfaces of the container holders  20  helps prevent unwanted twisting of the containers  1  during compression of a container group  3 . 1 . This friction material  26  generates increased friction between a particular container  1  and its container holder  20 . 
         [0049]    In the illustrated embodiment, three clamp heads  12  combine to form a clamp unit  13 . As shown in  FIG. 4 , a pair of connecting pieces  27  extends along the tops of the clamp heads  12 . These connecting pieces  27  connect clamp heads  12  together in an articulated manner to form the clamp unit  13 . The connecting pieces  27  are selected such that an axial distance x between the clamp heads  12 , or their holders  20 , corresponds to the diameter of one container  1 . 
         [0050]    Moreover, clamp heads  12  adjacent to each other, or their corresponding carriages  15 , are spaced apart from each other by a distance y selected to guarantee that the clamp units  13  will be able to go around curves at the ends of the first and second peripheral loops  14 . 1 ,  14 . 2 . 
         [0051]    A rotating rigid chain  28  drives the clamp units  13  away from a transfer region near the transport stars  9  along the inner paths  14 . 1 . 1 ,  14 . 2 . 1  and drives them back towards the transport stars  9  via the outer paths  14 . 1 . 2 ,  14 . 2 . 2 , on which the clamp units  13  are returned to the transfer regions. The chain  28  includes push links  29  at locations corresponding to the locations of the clamp units  13 . The first pilot pin  23  protrudes downwards over the guide cam  25  far enough so that the push link  29  can grasp it. In the illustrated embodiment, the first pilot pin  23  is provided on the subsequent clamp head  12  of each clamp unit  13  relative to the second transport direction B. 
         [0052]    Referring now to  FIG. 6 , a third pilot pin  30  protrudes upward from a top of a clamp head  12  of each clamp unit  13 . In the illustrated embodiment this is the next clamp head  12  of each clamp unit  13  relative to second transport direction B. When the clamp unit  13  reaches a diversion region, the third pilot pin  30  engages the teeth of the cog wheel  31  at that diversion region. As the cog wheel  31  rotates, it uses the third pilot pin  30  to drive the clamp unit  13 . 
         [0053]    Meanwhile, when the chain  28  reaches the cog wheel  31 , it traverses a path such that the first pilot pin  23  no longer engages the push links  29 . As a result, when traversing the diversion regions of the first and second peripheral loops  14 . 1 ,  14 . 2 , the clamp unit  13  moves only under the influence of the cog wheel  31 . This also results in perfect synchrony between the movement of the clamp unit  13  and the transport star  9  when the clamp unit  13  is in the region of the transport section  11  on the transport stars  9 . 
         [0054]    A variety of different implementations of the connecting pieces  27  is possible. In some embodiments, the connecting pieces  27  are connecting rods. In others, the connecting pieces  27  are hydraulic or pneumatic cylinders. 
         [0055]    Other measures are also possible to achieve a compression of the container group  3 . 1  in the second transport direction B. For example, in one method, when headpieces  19  move in the clamping direction C, there is also a reduction in the distance y between the clamp heads  12  of the clamp unit  13 . In another method, clamping of the containers  1  in the second transport direction B or against the second transport direction B can be achieved by making the axial distance x separating the container holders  20  from each other be slightly smaller than the diameters of the containers  1 . 
         [0056]    Some embodiments directly transfer containers  1  from the treatment star  8  by the peripheral path  14  or by clamp units  13  arranged along the peripheral path  14  in combination with the foregoing elements and functions. Such embodiments omit the transport star  9 . 
         [0057]    In all of the foregoing embodiments, it is useful to provide a curved or opposing guard-rail through to the crosswise approach to the opposite container stream. Such a curved or opposing guard-rail prevents the containers from rolling off. In some embodiments, the guard-rail includes rollers. In others, it includes an endlessly rotating belt. 
         [0058]    In the embodiments described above, a mechanical drive moves the clamp units  13 . In particular, the clamp units  13  engage chains  28  and cog wheels  31 . 
         [0059]    However, this is not the only way to drive the clamp units  13 . In a further embodiment, at least one clamp head  12  of each clamp unit  13  is a circulating armature of an electric linear motor. In these embodiments, it is possible to implement individual control over individual clamp units  13 . Another advantage of using an electric linear motor is a reduction in the number of clamp units  13  that are needed. This is because returning clamp units  13  can be accelerated as they traverse the outer paths  14 . 1 . 2 ,  14 . 2 . 2 . 
         [0060]    Yet another advantage of an embodiment that uses an electric linear drive is that it is no longer necessary to connect the clamp heads  12  mechanically to a clamp unit  13 . Instead, individual clamp heads  12  can be brought together to dynamically form clamp units  13  on an as-needed basis. 
         [0061]    For example, a particular clamp unit  13  might exist only until the compression of the container groups  3 . 1 , or until the production of the packages  3 , while in the next pass the same clamp heads  12  are put together in a different way to form different clamp units  13 . This permits considerable flexibility in the use of the clamp heads  12 , and potentially reduces the number of these clamp heads  12  needed in the packaging device  4 . 
         [0062]    A clamp head  12  that is an armature of a linear drive preferably includes a drive winding. Along the first and second peripheral loops  14 . 1 ,  14 . 2 , corresponding magnetic windings or permanent magnets form magnetic poles of changing polarity. 
         [0063]    In those cases in which the clamp heads  12  are part of a linear drive, it is possible to control compression of the container group  3 . 1  along the second transport direction B by individually controlling movement of the clamp heads  12  in second transport direction B and/or against the second transport direction B. 
         [0064]    In all embodiments, the headpieces  19  provided at the clamp heads  12  can be replaced quickly and easily whenever a format change is required. This makes it easier to reconfigure the device  4  to accommodate different kinds of containers. In addition, in all the embodiments, clamp heads  12  compress container grips  3 . 1  and connect containers  1  to each other through exertion of forces directed radially onto the containers  1 , thus pressing containers  1  that lie opposite each other against each other. Additionally, the clamp heads  12  exert, by appropriate means, a force directed onto the containers  1  such that adjacent containers, which are held between two clamp units  13  lying opposite each other, are pressed against each other.