Abstract:
A unit ( 10 ) for filling containers ( 14 ), includes an insulator ( 16 ) having a body ( 18 ) provided with an inlet (E) and an outlet (S), the structure ( 20 ) of the body ( 18 ) defining a space (V) forming an aseptic working region ( 22 ) and including insufflation elements ( 28 ) which are arranged in the upper part of the insulator ( 16 ) and are able to insufflate a sterile air flow for creating an overpressure inside the space (V). The insufflation elements ( 28 ) are arranged in the insulator ( 16 ) in such a way as to project a laminar-type flow (F) to lick the outer surface ( 44 ) of the containers ( 14 ), and the insulator ( 16 ) includes evacuation elements ( 48 ) which are separate from the inlet (E) and the outlet (S) and used to enable a controlled evacuation of the insufflated sterile air flow (F).

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a container filling unit comprising an insulator, especially for a production installation. 
     2. Description of the Related Art 
     Numerous container production installations are known, in particular for bottles, such as the installation described in the document EP-B1-1,012,047. 
     Such a manufacturing installation generally comprises various units between which are arranged transfer means so as to be able to carry out the operations of the manufacturing process in succession from the formation of the container through to obtaining a filled and plugged container forming a finished product. 
     In an installation manufacturing bottles made of plastic material such as PET (polyethylene terephthalate), the first step, upstream, is to transform bottle preforms in a blowing unit, the forming being done by the blowing or the stretching/blowing in a mold of a preform previously heated in an oven. 
     Generally, the blowing unit is incorporated in the manufacturing installation so as to obtain a compact, single-piece installation, able to carry out all of the manufacturing process from the start through to obtaining finished products ready for marketing. As a variant, the unit is still arranged upstream so that the bottles produced can then directly feed the input of an installation combining all the units that follow it according to the manufacturing process. 
     The installation represented in  FIG. 1  of this document mainly comprises, in addition to the abovementioned blowing unit, a cleaning unit in which a disinfecting or sterilizing treatment is carried out in order to decontaminate the interior and/or the exterior of the bottle, a filling unit and a plugging unit. 
     The manufacturing installation represented in  FIG. 1  of the document EP-B1-1,012,047 comprises a sterile body delimiting a volume inside which are arranged the various units so that the manufacturing process is performed in an aseptic or sterile environment suitable for limiting the risks of contamination of the bottles produced. 
     In the manufacturing process, the container filling operation is usually recognized as the most sensitive operation with regard to the risks of contamination, in particular of airborne particle contaminations by germs, bacteria, etc., likely to contaminate notably the internal volume of the container. 
     This is why, in addition to the sterilizing or disinfecting treatments directly targeting the liquid and the container, in particular its internal wall, other means are generally implemented to reduce the risks of contamination, most particularly during filling. 
     In addition to the presence of a general body intended to isolate, from the surrounding atmosphere, an internal space inside which are arranged the manufacturing units of the installation, it is known to equip the filling unit with an insulator. 
     By definition, an insulator is a body that makes it possible to carry out operations with no risk of contamination. 
       FIG. 1  shows an example of such an insulator of a filling unit according to the state of the art known to the applicant, but which does not, however, give full satisfaction. 
     In practice, it has been observed for such a filling unit equipped with an insulator, that there notably remains a risk of contamination by particles that might be present on the external surface of the container and that might be likely to be detached by the turbulent air flow that is insufflated into the body of the insulator to create an overpressure therein. 
     SUMMARY OF THE INVENTION 
     The aim of the invention is therefore to resolve the abovementioned drawbacks and notably propose a solution that makes it possible to reduce the risks of particle contamination in such a filling unit comprising an insulator. 
     To this end, the invention proposes a unit for filling containers, especially for a container production installation, which comprises an insulator comprising an outer body provided with an inlet and an outlet, the body delimiting, with an internal structure, a volume forming an aseptic working area and comprising means of insufflating sterile air which, arranged at the top part of the insulator, are able to insufflate a flow of sterile air for creating an overpressure inside the volume, characterized in that the sterile air insufflation means are arranged in the top part of the insulator so as to project a laminar flow of sterile air to sweep over the outer surface of the containers and in that the insulator comprises, in the bottom part, exhaust means, separate from the inlet and from the outlet, intended to allow a controlled evacuation of the laminar flow of insufflated sterile air. 
     By combining the arrangement of the insufflation means and of the exhaust means according to the invention, if a particle present on the outer surface of the container becomes detached, it is then immediately picked up by the laminar flow of sterile air sweeping over the container and directly evacuated via the exhaust means out of the body of the insulator. 
     Advantageously, the exhaust means are produced in a simple and economical manner by omitting to fill the bottom dynamic seal of the insulator of the filling unit with sterilizing liquid, thus creating a passage through which the laminar flow of sterile air flows naturally. 
     The invention can therefore easily be implemented on an existing filling unit with insulator. 
     According to other characteristics of the invention:
         the sterile air insufflation means are arranged with a predetermined inclination corresponding to an angle which is defined by the intersection of a main axis of the insufflation means with a reference vertical axis of the insulator;   the reference vertical axis of the insulator is parallel to the main axis of the containers which extend vertically in order to be filled;   the exhaust means are located as close as possible to the containers in order for the laminar flow of insufflated sterile air to be primarily evacuated from the body by said exhaust means;   the bore of the exhaust means is greater than the bore of the inlet and/or the outlet of the insulator that are provided in the body;   the insulator comprises extraction means associated with the exhaust means so as to control the evacuation of the laminar flow of sterile air;   the insulator of the filling unit comprises dynamic sealing means, respectively at least one top dynamic seal and one bottom dynamic seal, which are arranged between the body and a moving part of the internal structure, each of said dynamic seals comprising a first sealing element and a second sealing element between which elements sealing is ensured by the presence of a sterilizing liquid in which at least a part of the first and second elements is immersed and the exhaust means consist of the bottom dynamic seal between the first and second elements of which no sterilizing liquid is introduced so as to create a passage intended to directly evacuate, after the containers have been swept over, the laminar flow of insufflated sterile air;   the laminar flow of sterile air is able to drive toward the exhaust means any contaminating particles present on the outer surface of the container, which in particular are likely to contaminate the internal volume of the containers;   the value of the overpressure created in the aseptic working area of the insulator is less than or equal to 15 pascal (Pa) so as to maintain a laminar-type flow for the flow of insufflated sterile air.       

     The invention also proposes a container manufacturing installation comprising a filling unit, characterized in that the installation comprises a containment body with controlled atmosphere delimiting an internal volume in which are arranged at least one cleaning unit, the filling unit and a plugging unit and associated sterile air insufflation means able to create an overpressure in said internal volume of the containment body, the value of which overpressure is less than the value of the overpressure created in the aseptic working area of the insulator. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING FIGURES 
       Other features and benefits of the invention will become apparent on reading the following detailed description, for an understanding of which reference should be made to the appended drawings in which: 
         FIG. 1  is a diagrammatic view of a filling unit according to the state of the art comprising an insulator equipped with sterile air insufflation means, which illustrates in particular the turbulent flow of the sterile air flow in the aseptic working area in which at least the filling of the containers is carried out; 
         FIG. 2  is a diagrammatic view of a filling unit according to the invention which illustrates the laminar flow of the sterile air flow in the aseptic working area which sweeps over the outer surface of the container before being evacuated by the associated exhaust means. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In the following description and the claims, the terms such as “top” and “bottom”, “axial” and “radial” and the longitudinal, vertical and transversal orientations will be used in a nonlimiting manner to respectively designate elements according to the definitions given in the description and relative to the trihedron (L, V, T) represented in the figures. 
     In the description, identical, similar or analogous elements will be designated by the same reference numerals. 
     In order to explain the invention,  FIG. 1  shows a filling unit  10  according to the state of the art, which is notably able to be incorporated in a container production installation  12 . 
     Hereinafter in this description, the term “container” designates, in a generic and nonlimiting manner, all types of containers  14 , such as bottles, flasks, etc. 
     The container filling unit  10  comprises an insulator  16  in order to carry out the container filling operations in a controlled environment with, in particular, high disinfection or sterilization conditions suitable for ensuring a reduced risk of contamination of the containers  14  by pathogenic particles or agents, such as bacteria, germs, etc. 
     As is known, such an insulator  16  comprises an outer body  18  which is respectively provided with an inlet opening “E” through which the containers  14  to be filled, coming from upstream, are introduced into the insulator  16  and an outlet opening “S” through which the containers  14  are evacuated downstream out of the body  18  of the insulator  16 . 
     The insulator  16  here comprises an internal structure  20  which is centrally arranged and which is topped and surrounded by the body  18 . 
     The body  18  delimits, with the internal structure  20 , a volume “V” forming an aseptic working area  22  which, for example, has an annular form and is radially contained between the internal face of a wall  24  delimiting the internal structure  20  and the internal face of a wall  26  of the body  18 . 
     The insulator  16  also comprises sterile air insufflation means  28  which are usually arranged in the top part of the insulator  16  in order to insufflate a flow “f” of sterile air inside the volume “V” forming the aseptic working area  22  in which the containers  14  introduced through the inlet opening E are intended to be filled in succession. 
     The flow f of sterile air insufflated by the insufflation means  28  is for creating an overpressure inside the volume V to insulate the aseptic working area  22  from the risks of external contaminations from particles (germs, viruses, bacteria, etc.) that are likely to be notably present in the surrounding air situated outside the body  18  and around the insulator  16 . 
     In practice, the filling of the container  14  is usually considered to be the operation during which the risk of contamination of the container, in particular of its internal volume, is most critical. 
     By virtue of the overpressure created inside the body  18  of the insulator  16 , such particles cannot penetrate into the aseptic working area  22  from the outside in an airborne manner. 
     Thus, the degree of sterilization or disinfection is at least partly controlled. In practice, the control is not, however, total given that particles are likely to be introduced into the insulator  16  by the containers  14 . 
     This is also the reason why the insulator  16  comprises dynamic sealing means  30  respectively consisting here of a top dynamic seal  32  and a bottom dynamic seal  34 . 
     In practice, the insulator  16  comprises a top part  36  of the internal structure  20  which is mounted to move rotation-wise relative to the body  18  and relative to a fixed bottom part  38  of the internal structure  20  forming a rack. 
     The dynamic sealing means  30  are arranged between the body  18  and said moving top part  36  of the internal structure  20  of the insulator  16 . 
     The moving part  36  usually comprises a carousel provided with a plurality of filling stations which are distributed circumferentially and which can each be moved with a container from the inlet opening E to the outlet opening S while, during this travel, at least filling the container  14 . 
     The top dynamic seal  32  and the bottom dynamic seal  34  forming the dynamic sealing means  30  are, for example, arranged at the top and bottom ends of the wall  24 , at the junction between the internal structure  20  and the body  18 . 
     The top dynamic seal  32  and the bottom dynamic seal  34  each respectively comprise a first sealing element  32   a ,  34   a  and a second sealing element  32   b ,  34   b  between which sealing is ensured by the presence of a sterilizing liquid  40  in which at least a part of said first and second elements is immersed. 
     Consequently, the containers  14  introduced through the inlet E are the main possible propagation vector for particles. 
     The containers  14  therefore usually undergo an aseptic treatment upstream of the insulator  16 , after which treatment the containers  14  are taken up by conventional transfer means (not represented) and introduced continuously through the inlet opening E into the body  18  of the insulator  16 , in the aseptic working area  22  in order to be filled therein. 
     The flow f of sterile air insufflated by the insufflation means  28  flows vertically from top to bottom in a turbulent-type flow through the aseptic working area  22  in which the containers  14  are notably filled. 
     In practice, the flow f of sterile air flows from the insufflation means  28  by partly “falling” directly above the containers  14  and the filling means  42  borne by the carousel  36  that forms the moving part of the internal structure  20 . 
     The rotation of the assembly  14 ,  36 ,  42  therefore provokes strong eddies in the flow f of air which is therefore necessarily a turbulent-type flow. 
     Furthermore, the flow f of sterile air maintaining the overpressure inside the insulator  16  is evacuated through the inlet E and outlet S openings of the body  18 , inlet E and outlet S openings through which the containers  14  are continually introduced or evacuated in such a way as to further help in provoking a flow f of sterile air that is turbulent. 
     Thus, it will be understood that, if one of the containers  14  comprises, for example on its outer surface  44 , a contaminating particle such as a bacterium, a germ, etc., there is then a risk of airborne contamination of the aseptic working area  22  by this particle and more particularly of contamination of the internal volume  46  of one of the containers  14  introduced into said aseptic working area  22  in order to be filled. 
     The aim of the invention is consequently to propose a simple and economic solution that makes it possible to control the risk of particle contamination by such particles that would be likely to be present on the outer surface  44  of the container  14  despite the disinfecting or sterilizing treatment operations on the container  14  performed upstream of the insulator  16 . 
     According to the invention, the sterile air insufflation means  28  are arranged in the top part of the insulator  16  so as to project a laminar flow F of sterile air to sweep over the outer wall  44  of the containers  14  and the insulator  16  comprises, in the bottom part, exhaust means  48  to allow for a controlled evacuation of the flow F of insufflated sterile air. 
       FIG. 2  shows an example of a unit  10  for filling containers  14  according to the invention which will be described hereinbelow by comparison with the unit represented in  FIG. 1 . 
     Consequently, the means of the filling unit  10  according to the invention that are similar or identical will not be described again in detail and will be designated by the same reference numerals as those used for the unit according to the state of the art represented in  FIG. 1 . 
     Advantageously, the insufflation means  28  are arranged in the top part of the insulator  16 , in this case of its body  18 , with a predetermined inclination of angle “α”. 
     The angle α of inclination is defined by the intersection of a main axis A of the insufflation means  28  with reference vertical axis X of the insulator  16 . 
     The value of the angle α is determined in such a way that the laminar flow F of sterile air flows vertically overall from top to bottom while sweeping over the outer wall  44  of each container  14  introduced into the aseptic working area  22  in order to be filled. 
     The reference vertical axis X of the insulator  16  is in this case parallel to the main axis of the containers  14  which extend vertically below filling means  42  able to introduce a predetermined quantity of liquid into each container. 
     Conventionally, the filling is done by means of a filling spout  50  that can be introduced into an opening  52  of the container  14  held in position by support means  54  in order to pour the liquid therein. 
     As can be seen in  FIG. 2 , the laminar flow F of sterile air flows well in a laminar-type, and therefore non-turbulent, flow before being evacuated by the exhaust means  48 . 
     Advantageously, the exhaust means  48  are located as close as possible to the containers  14  and as far away as possible from the inlet E and outlet S openings of the insulator  16 . 
     Furthermore, the bore of the exhaust means  48  is advantageously greater than the bore of the inlet E and/or the outlet S of the insulator  16  provided in the wall  26  of the body  18 . 
     Advantageously, the laminar flow F of sterile air insufflated by the insufflation means  28  is mainly evacuated out of the body  18  by said exhaust means  48  and no longer by the inlet E or outlet S openings so that the flow of the laminar flow F through the aseptic working area  22  is totally controlled to further reduce the risk of particle contamination of the internal volume  46  of one of the containers  14  or of a part of the unit  10  such as the filling means  42 . 
     In practice, in a unit  10  comprising insufflation  28  and exhaust  48  means arranged according to the teachings of the invention, if a particle present on the outer surface  44  of the container  14  becomes detached, this particle is then immediately picked up by the laminar flow F of sterile air sweeping over the container  14  and driven downward by the laminar flow F so as to be directly evacuated out of the aseptic working area  22  via the exhaust means  48  of the insulator  16 . 
     Advantageously, the laminar flow F of sterile air can drive, toward the exhaust means  48 , the air contained inside each container  14  which air, during filling operations, is progressively expelled through the top opening  52  for filling the container  14 . 
     Advantageously, the insulator  16  comprises extraction means  56  associated with the exhaust means  48  so as to provoke an additional suction effect and ensure that the laminar flow F of sterile air is evacuated mainly, that is to say almost totally, by the exhaust means  48 . 
     Preferably, the air of the laminar flow F sucked in by the extraction means  56  is evacuated outside into the atmosphere so that the contaminating particles present in this air cannot contaminate, in an installation  12 , the other units adjacent to the filling unit  10 . 
     In a variant, the air of the laminar flow F sucked in by the extraction means  56  could be recycled to feed, in return, the insufflation means  28 , the recycling comprising treatment operations, notably filtration and/or sterilization, of the extracted air before it is reintroduced in order to be able to ensure that it is free of all contaminating particles. 
     According to a preferred embodiment of the invention, the exhaust means  48  comprise the bottom dynamic seal  34  between the first and second elements  34   a ,  34   b  of which no sterilizing liquid  40  is introduced so as to deliberately create a passage able to directly evacuate, after the containers  14  have been swept over, the laminar flow F of sterile air insufflated by the insufflation means  28 . 
     Advantageously, the bottom dynamic seal  34  can therefore receive or not receive sterilizing liquid  40  in order to form, in a particularly simple and economical manner, the exhaust means  48  associated with the insufflation means  28  inclined according to the invention. 
     The sterilizing liquid  40  is thus introduced selectively into the bottom dynamic seal  34  according to whether the requirement is respectively to open, during container  14  filling operations, a passage for the controlled evacuation of the laminar flow F through said bottom dynamic seal  34 , or to close said passage, for example, to re-establish sealing during insulator  16  servicing operations, in particular decontamination of the aseptic working area  22 . 
     In a variant, the exhaust means  48  are produced in a given part of the insulator  16 , for example in the wall  24  of the internal structure  20 , the dynamic sealing means  30 ,  32  and  34  then being kept operational. 
     The invention can consequently be easily implemented in a filling unit  10  simply by modifying the insufflation means  28  for the laminar flow F, without other substantial modifications, in particular for producing the exhaust means  48  for the laminar flow F when the latter consist of the opening of the bottom seal  34 . 
     Preferably, the value of the overpressure created in the aseptic working area  22  of the insulator  16  is less than or equal to 15 pascal (Pa) in order for the flow of the sterile air flow to be always of laminar type. 
     Advantageously, the filling unit  10  with insulator  16  that has just been described can be incorporated in an installation  12  for manufacturing containers  14  that is not represented in detail. 
     Such an installation  12  is, for example, of single-piece type, like the installation represented in  FIG. 1  of the abovementioned document EP-B1-1,012,047. 
     Advantageously, such an installation  12  for manufacturing containers  14  comprises a containment body (not represented) with controlled atmosphere delimiting an internal volume inside which the various units needed to implement the manufacturing process are arranged. 
     For this, the installation  12  comprises at least one cleaning unit, one filling unit according to the invention and one plugging unit to seal the filled containers  14 . 
     The installation  12  also comprises associated sterile air insufflation means that can create an overpressure in said internal volume of the containment body. 
     Advantageously, the value of the overpressure created in the internal volume of the containment body is less than the value of the overpressure created in the aseptic working area  22  of the insulator  16  of the filling unit  10 . 
     The value of the overpressure created in the aseptic working area  22  of the insulator  16  of the filling unit  10  is, for example, between 10 and 15 pascal, whereas the value of the overpressure created in the containment body is of the order of 7 pascal. 
     Advantageously, a positive pressure gradient is created relative to the atmospheric pressure outside the installation, the value of the overpressure increasing according to the scale of the particle contamination risks. 
     By virtue of such a pressure gradient, the circulation of air in the installation  12  is always from the cleanest and most sensitive areas, in this case the aseptic working area  22  of the insulator  16  of the filling unit  10 , toward the less sensitive areas, namely, in succession, the internal volume of the containment body comprising the other units then the atmosphere outside the body of the installation. 
     Preferably, such an installation  12  for manufacturing containers comprises, upstream of the cleaning unit, a blowing unit able to produce the containers  14 , for example bottles made of PET, obtained by blowing or stretching/blowing from preforms previously heated in an oven before being introduced into a mold.