Abstract:
A method for packaging articles ( 1 ) in blister packs (P) comprising an accommodating part ( 2 ) which accommodates the article ( 1 ) and, once the article ( 1 ) has been accommodated, is closed by a strip ( 5 ) of material, wherein the accommodating part ( 2 ) is adapted, at least in part, to the article ( 1 ) which is to be packaged.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The invention relates to a method for packaging articles in blister packs comprising an accommodating part which accommodates the article and, once the article has been accommodated, is closed by a tool strip and to an apparatus for this purpose. 
         [0002]    The term blister, refers, in the packaging industry, to a usually transparent pack which serves for accommodating a multiplicity of articles. The so-called blistering of medicinal products is known in particular. This involves tablet packs in which the tablets can be pushed through a rear wall made of aluminum. Nowadays, however, it is also the case that any other desired articles, and in particular also medical implements are provided in blister packs. 
         [0003]    For example DE 10 2010 032 944 A1 discloses a blister pack for toothbrushes. First of all here blister cavities for accommodating the articles are formed from a strip of plastics material, it being possible for this to take place, for example, by heating and a vacuum being applied. Once the article has been inserted, said blister cavities are closed, or welded by an appropriate cover layer made of cardboard or plastic film. 
         [0004]    In addition, DE 20 2006 004 323 U1 discloses a blister pack for contact lenses. Here too the blister pack comprises a blister shell and a cover film. The blister shell is produced in one piece, by thermoforming, from a strip of plastic film. It comprises an essentially planar main body, from which a cup and a recess are thermoformed. A fastening surface runs around the cup, on the upper side of the planar main body. The cover film is connected to the blister shell in a sealing and manually releasable manner along the encompassing fastening surface and encloses the contact lens and the liquid in a sterile state. 
         [0005]    The problem nowadays, however, is that it is precisely in the medical sector where blister packs have to meet ever more stringent requirements. They have to consist of specific plastics materials which meet all hygiene-related requirements, and at the same time they have to be easy to produce and use. On the other hand, the batch numbers of individual articles are decreasing all the time, and therefore a multiplicity of different blister packs have to be kept available for the multiplicity of different articles. 
       SUMMARY OF THE INVENTION 
       [0006]    The object of the present invention is that of developing a method of the type mentioned above which makes it possible to provide extremely high-quality blister packs in a cost-effective manner, since the same design of blister pack can be used for a multiplicity of articles. 
         [0007]    The object is achieved in that the accommodating part is adapted, at least in part, to the article which is to be packaged. 
         [0008]    This basic concept of the present invention has the significant advantage that there is now no longer any need for a dedicated blister pack to be produced for each article which is to be packaged; rather, the same blister pack can be used for a multiplicity of articles, in accordance with the three-dimensional configuration of the latter. All that is required is to make available certain graduations in size of blister pack organized in terms of length, width and height of the articles. A blister pack with a relatively large accommodating part can always be used for a smaller article. 
         [0009]    In a preferred embodiment of the method,
       the accommodating part, together with the article therein, is inserted into a tool and   the region of the accommodating part above the tool is heated, whereupon,   in the region of the accommodating part around the article the accommodating part is vented from the inside or is subjected to pressure from the outside, and a space for the article therefore forms in the accommodating part, and   said space for the article is then closed by the strip of material.       
 
         [0014]    This means that the accommodating part of the blister pack can maintain its actual shape, but can nevertheless be used for a multiplicity of articles. The encompassing frame can maintain its sharp edges, which are necessary in order for the blister pack to be adjusted in automatic packaging machines. As before, this frame continues to protect the product in the accommodating part. Overall, it is also the case that the accommodating part remains stackable, since it comprises a frame-encompassed interior which, while being of any desired shape, is identical to others. This means that these accommodating parts can also be stacked and transported easily to the filling machine. It is, of course, possible for the inner accommodating space to be of any desired geometrical configuration. For a multiplicity of products, however, it is necessary to have only a small number of geometrical accommodating-space configurations. This means that said accommodating parts can be produced in very large quantities which significantly reduces the cost of production. Of course, it is also thus possible, in turn, for higher-quality material to be used. Nevertheless, the method remains cost-effective. Furthermore, it is, of course particularly advantageous that the article which is to be packaged is relatively secure in the accommodating part, and this provides for protected transportation of the article. 
         [0015]    An essential constituent part of the method according to the invention is that only a sub-region of the accommodating part is heated. This is the sub-region which should be located around the article which is to be packaged. This is usually the base of the accommodating space, or also just a sub-region of said base. All this should be covered by the concept of the invention. 
         [0016]    Venting of the accommodating part has the advantage, over subjecting the latter to pressure, of the operation being easier to control. Increasing the vacuum makes it possible to determine whether sufficient venting has taken place, and therefore the accommodating part has positioned itself for the most part, or to the required extent, around the article. Subjecting the accommodating part to pressure from the outside in order for said accommodating part to be deformed around the article is possible and conceivable and, in addition, has the advantage that the heated region of the accommodating part is cooled again. However, this has to be controlled very precisely in order to preclude premature cooling, as a result of which the article can be enclosed only in part, if at all. For this reason, the vacuum variant of the invention will probably be preferred. 
         [0017]    A further improvement of the method according to the invention resides in the fact that, prior to being heated, the accommodating part with the article inserted therein is closed by a sheet. Following heating, or once the article has been enclosed, the accommodating part has to be closed by the strip of material. For this purpose, it is usually necessary for the accommodating part, together with the article, to be removed from the tool and rotated. There is a risk here of the article dropping out of the accommodating part. This is prevented by a sheet which has been inserted into, or placed on, the accommodating part. It is possible for said sheet to be removed prior to closure by the strip of material or else also to be configured such that it remains in its use position. 
         [0018]    As has just been mentioned, the accommodating part with the article inserted therein is closed, in particular sealed, by a strip of material. The material of which said strip of material consists is of little importance. Preferred materials are plastic or cellulose films or aluminum foils. 
         [0019]    The invention also covers an apparatus for implementing the method described above and comprising at least two tool parts which accommodate between them the accommodating part with the article inserted therein. The term tool part here can be interpreted very broadly. In one exemplary embodiment in which the method according to the invention is operated using a vacuum, said tool part has a heat dispenser for partially heating the accommodating part above the article inserted therein. The other tool part is assigned a vacuum device, to provide for evacuation of the space around the article inserted therein. 
         [0020]    In the method according to the invention which operates using pressure, the accommodating part with the article inserted therein rests on a tool part, of whatever kind, and is subjected to heat and, at the same time, pressure by the other tool part. A suitable compressed gas is used for this purpose. It is of course, also conceivable, however to have other pressure media or pressure generators, even mechanical pressure generators, such as appropriate rams or the like, which form the accommodating part around the article which is to be removed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]    Further advantages, features and details of the invention can be gathered from the following description of preferred exemplary embodiments and with reference to the drawing, in which: 
           [0022]      FIG. 1  shows a plan view of a blister pack; and 
           [0023]      FIGS. 2   a )- c ) show schematic illustrations of the method according to the invention for packaging articles in blister packs. 
       
    
    
     DETAILED DESCRIPTION 
       [0024]      FIG. 1  shows an article  1 , for example a pair of forceps, inserted into a blister pack P. The blister pack P here forms, in an accommodating part  2 , an accommodating space  3  which is intended for accommodating the article  1  and, in many cases, may be of transparent configuration. Said accommodating space  3  is surrounded by a periphery  4 , which is of flat and usually rigid design. 
         [0025]    In order to allow better handling of such blister packs P, the periphery  4  requires, to a certain extent, sharp edges, so as to provide for automated packaging control. Said frame  4  also protects the product in the accommodating space  3 . It should also be emphasized that such accommodating parts  2  are easily stackable 
         [0026]    Once the article  1  has been inserted into the accommodating space  3  of the accommodating part  2  of the blister pack P, said accommodating space  3  is closed, usually sealed, by a strip of material. A plastic film, an aluminum foil or also cardboard is a recommended material to use for the strip  5 . This is of secondary importance to the invention. 
         [0027]    The method according to the invention for packaging the article  1  in the blister pack P takes place as follows: 
         [0028]    According to  FIG. 2 a   ), the accommodating part  2  and the article  1  are transferred together into a skin tool  6 . 1 ,  6 . 2 . It is also the case here that a sheet  7  is inserted between a lower tool part  6 . 2  and the article  1 , or the accommodating part  2 , said sheet  7  merely having the task of preventing the article  1  from dropping out of the accommodating part  2  when the accommodating part  2  is being removed from the tool once the article  1  has been inserted into the accommodating part  2 . 
         [0029]    It is also indicated that the lower tool part  6 . 2  has a venting bore  8 , which is connected to a vacuum source (not shown specifically). 
         [0030]    In the next method step according to  FIG. 2 b   ), the upper tool part  6 . 1  is moved toward the lower tool part  6 . 2  and, as indicated by arrows  9 , a base  10  of the accommodating part  2  is subjected to heat. As a result, the accommodating part  2  is heated partially, that is to say only in the region of the base  10  or only in a sub-region of the base  10 , and this allows said base to deform. 
         [0031]    The accommodating space  3  is then evacuated through the venting bore  8  as a result of the vacuum being applied, wherein the base  10  of the accommodating part  2  deforms. It positions itself over the article  1  and encapsulates said article  1 . So to speak, it replicates the article  1 . 
         [0032]    In a further method step, the tool  6 . 1 ,  6 . 2  is opened and the accommodating part  2 , as indicated in  FIG. 2 c   ), is rotated. It is then possible for the sheet  7  to be removed or else to remain on the accommodating part  2 . The accommodating space  3  is then closed by the strip  5  of material, said strip  5  of material being welded onto the frame  4  of the accommodating part  2 . The article  1  is thus secured in the accommodating space  3 .