Abstract:
In a container-filling machine, a filling element includes a housing, a sealing tulip, and a bellows. The housing has a housing section and an orifice. The sealing tulip moves relative to the housing section along an axis between a raised and a lowered position. The bellows surrounds the axis. The bellows&#39; two ends connect tightly to the housing and the tulip respectively. As a result, the bellows seals a transition between the tulip and the housing.

Description:
RELATED APPLICATIONS 
       [0001]    This application is the national stage, under 35 USC 371, of PCT application PCT/EP2013/002088, filed on Jul. 13, 2013, which claims the benefit of the Jul. 30, 2012 priority date of German application DE 10 2012 014 957.3, the content of which is herein incorporated by reference. 
     
    
     FIELD OF INVENTION 
       [0002]    The invention relates to a filling element for filling systems or filling machines for filling containers, such as cans. 
       BACKGROUND 
       [0003]    A variety of filling machines for filling containers are known. These container include cans. These cans are usually filled with a liquid filling material, such as beer, or soft drinks. These filling machines include, in particular, pressure-filling machines, in which there is a sealed contact between a filling element and the can. 
         [0004]    In typical machines, a sealing tulip causes the sealed contact between the filling element and a container. This is achieved by lowering the sealing tulip against the container to form a seal against an edge of the container&#39;s orifice. This creates a space that encloses the container orifice and the delivery orifice of the filling element. This space is sealed off from the exterior. 
         [0005]    A sealing tulip is formed by an annular body that is disposed on a section of the filling element housing so as to be displaceable along a direction parallel to a filling element axis between a raised position and the lowered position. A seal encircles the filling element axis between the annular body of the sealing tulip and the outer face of the housing section so as to seal off the transition between the annular body and the filling element housing. Because the tulip is constantly moving up and down, this seal is a sliding seal. 
         [0006]    While the filling machine is in operation, the sliding seal, like most moving parts, must constantly be lubricated to minimize wear. The lubricant is typically water. 
         [0007]    A difficulty that arises with sliding seals is that it is difficult to prevent this lubricating water from also dripping into he containers being filled. Inevitably, bacteria and dirt particles manage to get past the sliding seal. This lubricating water can thus carry bacteria and dirt into the drink. Not surprisingly, consumers tend to regard the introduction of seal-lubricating water into their drink as rather undesirable. 
       SUMMARY 
       [0008]    An object of the invention is to provide a filling element that avoids having a sliding seal between the sealing tulip and the filling element housing, thus eliminating the disadvantages that are associated with a sliding seal. 
         [0009]    In one aspect, the invention features an apparatus for filling containers with liquid filling material. Such an apparatus includes a filling element with a filling-element housing, a sealing tulip, and a bellows. The housing includes a first housing section and a delivery orifice for controlled delivery of the liquid filling material into a container. The sealing tulip is movable relative to the housing section along a filling element axis between raised and lowered positions. In the lowered position, the sealing tulip is sealed against an orifice edge of the container. Meanwhile, the bellows surrounds the filling element axis. A first end of the bellows connects tightly to the filling element housing, and a second end of the bellows connects tightly to the sealing tulip. The bellows thus seal a transition between the sealing tulip and the filling element housing. 
         [0010]    In some embodiments, the housing section includes an enveloping face. In these embodiments, the sealing tulip and the bellows surround the housing section on the enveloping face. This forms an annular gap between the enveloping face and an inner face of both the sealing tulip and the bellows. Among these embodiments are those in which the channel opens out into the annular gap thus formed. In some of these embodiments, the channel includes an opening that leads into the annular gap. The channel thus defines a channel axis oriented in a direction such that an angle between the channel axis and a notional plane that is perpendicular to the filling element axis is less than ninety degrees. In at least some cases, the channel axis is also arranged in a plane parallel to the filling element axis. 
         [0011]    In other embodiments, the housing section includes a cylindrical enveloping face. Some of these embodiments also have a channel that opens out into an annular gap formed between the enveloping face and the bellows and sealing tulip at an end of the annular gap that lies away from the sealing tulip. 
         [0012]    In additional embodiments, which include a clamping ring, the housing also includes a second housing section and a step that connects it to the first housing section. This second housing section has a larger outer cross-section than the first housing section, hence the need for the connecting step. The connection is at an end that lies furthest from the delivery orifice. The clamping ring holds the bellows in a region of the step by clamping it against the filling element housing. 
         [0013]    In additional embodiments, the sealing tulip includes an annular body having inner and outer faces. A lower bellows section extends from the second end of the bellows away from the delivery orifice, while an upper bellows section is disposed between the lower bellows section and the first end of the bellows. The lower bellows section surrounds the filling element axis and extends from the upper bellows section into the annular body, where it is tightly connected to the inner face of the annular body. In some of these embodiments, the inner face of the annular body includes walls forming a recess, and the lower bellows section is tightly connected to the inner face at this recess. 
         [0014]    Some embodiments also include a filling machine having a rotor that rotates about a vertical machine axis. The rotor defines a plurality of filling positions for filling cans or other containers. In these embodiments, the filling element is one of many other identical filling elements disposed around the rotor at each filling position. 
         [0015]    In one aspect, the invention features a filling element that includes a housing, a sealing tulip, and a bellows. The housing has a housing section and an orifice. The sealing tulip moves relative to the housing section along an axis between a raised and a lowered position. The bellows surrounds the axis. The bellows&#39; two ends connect tightly to the housing and the tulip respectively. As a result, the bellows seals a transition between the tulip and the housing. 
         [0016]    The sealing tulip is also preferably configured as or acts as a centering tulip. In some embodiments, a cam follower effects the lifting motion of the tulip along the filling element axis between a raised starting position and a lowered working position. In these embodiments, the cam follower exerts contact pressure when the sealing tulip lies against an orifice edge of a container during filling. This contact pressure can assist pressure resulting from pre-tensioning and/or filling pressure. 
         [0017]    The pressing force generated by the pre-tensioning and filling pressure is determined, in essence, by the effective diameter of the bellows, taking into account the effective orifice cross-section of the container. The effective orifice cross-section corresponds to the portion not covered by the sealing tulip. The magnitude of this pressing force can be set by an appropriate choice of the effective diameter of the bellows. By altering the pre-tensioning and/or filling pressure, the component of the pressing force that results from that pressure can also be set and/or regulated and adapted to the particular container, in particular to its strength. 
         [0018]    In a preferred embodiment of the invention, there opens out into the annular gap that is formed between the bellows and the sealing tulip and that section of the filling element housing that is enclosed by these elements, at least one channel that, during a CIP cleaning and/or CIP sterilization of the filling system, is used to supply or expel a liquid cleaning and/or sterilization medium into or out of the annular gap. The channel opens out into this annular gap preferably at an upper end thereof, and preferably in a region of local attachment of the bellows. 
         [0019]    The channel opens out into the annular gap preferably at an angle and in such a way that the cleaning and/or disinfection medium leaving the channel flows through the annular gap from top to bottom in a spiral stream that, because of its high flow velocity and spiral course, optimally cleans and/or disinfects all the interior faces of the bellows, and in particular the surfaces inside the folds of the bellows. 
         [0020]    The inventive filling element is designed in particular for the pressure filling of cans or similar containers, and especially for pressurized filling with a high throughput. 
         [0021]    As used herein, “pressure-filling” means a filling method in which the container to be filled lies sealed against the filling element and in which, usually before the actual filling phase, i.e., before the liquid valve is opened, the container has been pre-tensioned through at least one controlled gas path configured in the filling element with a pressurized pre-tensioning gas, such as an inert gas, which is typically CO 2  gas, which the filling material entering the container during filling increasingly displaces as a return gas out of the container interior, through at least one controlled gas path configured in the filling element. This pre-tensioning phase can be preceded by other treatment phases, such as an evacuation of the container interior and/or a washing of the container interior with an inert gas such as CO 2 , through the gas paths configured in the filling element. 
         [0022]    As used herein, a container is in “a sealed position against the filling element” when the container that is to be filled lies with its container mouth pressed tightly against the filling element or against a sealing tulip. 
         [0023]    For the purpose of the invention the expressions “essentially”, “in essence” or “around” all mean variations from the respective exact value by ±10%, preferably by ±5% and/or variations in the form of changes insignificant for the function. 
         [0024]    Further embodiments, advantages and possible applications of the invention arise out of the following description of embodiments and out of the figures. All of the described and/or pictorially represented attributes whether alone or in any desired combination are fundamentally the subject matter of the invention independently of their synopsis in the claims or a retroactive application thereof. The content of the claims is also made an integral part of the description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0025]    The invention is explained in detail below through the use of an exemplary embodiment with reference to the figures. 
           [0026]      FIG. 1  shows a simplified view and partial section of a filling element according to the invention, together with a container that is to be filled; and 
           [0027]      FIG. 2  shows a simplified schematic view of a section through a filling element housing in the region of a channel or of a bore for supplying or expelling a CIP cleaning and/or sterilization medium. 
       
    
    
     DETAILED DESCRIPTION 
       [0028]      FIG. 1  shows a filling position  1  of a filling machine for the pressure-filling of containers  2 , such as cans with a liquid filling material, for example with a carbonated filling material, such as beer or soda pop. The filling position  1  has a filling element  3  that, together with a plurality of identical filling elements, is disposed on a periphery of a rotor  4  that is driven to rotate about a vertical machine axis. Under each filling element  3  is a platform  5  that is coupled to the rotor  4 . A container  2  to be filled stands upright, on its base, on this platform  5 . 
         [0029]    Each filling element  3  includes a filling element housing  6  in which is configured a liquid channel  7  for the filling material. At its upper region, which is not depicted in the figure, the liquid channel  7  connects to a reservoir provided on the rotor  4 . This reservoir supplies filling material for all filling elements  3  together. At its lower end, the filling element housing  6  forms an annular delivery orifice  8  for the filling material. 
         [0030]    Upstream of the delivery orifice  8 , in the direction of flow of the filling material, is a liquid valve  9 . The liquid valve  9  has a valve body  10  that is configured in the region of a lower end of a gas tube  11 . The gas tube  11  is arranged along a filling-element axis FA that is oriented parallel to a machine axis MA. A gas channel  12 , which is open on the underside of the filling element  3 , is formed in the gas tube  11 . 
         [0031]    The valve body  10  interacts with a valve seat in the liquid channel  7  and acts as a valve cam follower. An actuating device, not shown, causes the gas tube  11  to raise the valve body  10  from its closing position, as shown in  FIG. 1 , to open the liquid valve  9  and to then lower it again to close the liquid valve  9 . 
         [0032]    In its lower region, the filling-element housing  6  forms a tube-like housing section  6 . 1  with a reduced diameter. A sealing tulip  13 , which is able to move parallel to the filling element axis FA along the double arrow A, is provided on the tube-like housing section  6 . 1 , along with the delivery orifice  8  and the valve seat for the liquid valve  9 . The sealing tulip  13  has an annular body  13 . 1  that surrounds the tube-like housing section  6 . 1 . A distal portion of the annular body  13 . 1  transitions into a lower annular body section  13 . 1 . 1  that has an enlarged outer diameter. The lower annular body section  13 . 1 . 1  has an inner ring seal  14  and an outer lip seal  15 . The inner ring seal  14  concentrically surrounds the filling element axis FA. The outer lip seal  15  concentrically surrounds the inner ring seal  14  and the filling element axis FA. 
         [0033]    Bellows  16  seal the transition between the sealing tulip  13  or the annular body  13 . 1  and the filling element housing  6 . The bellows  16  have an upper edge, which lies further away from the delivery orifice  8 , and a lower edge, which lies closer to the delivery orifice  8 . 
         [0034]    The bellows  16  encircle the tube-like housing section  6 . 1  above the sealing tulip  13 . An upper edge of the bellows  16  connects to the filling element housing  6 . A lower edge of the bellows  16  connects to the top of the sealing tulip  13 , which is the portion of the sealing tulip  13  that is furthest from faces away from the inner ring seal  14  and the outer lip seal  15 . The bellows  16  are made from a suitable elastic and/or flexible material, for example TEFLON (R). As  FIG. 1  also shows, both the sealing tulip  13  and the bellows  16  surround the tube-like housing section  6 . 1  at a distance. This creates an annular gap  19  between the tube-like housing section  6 . 1 , the bellows  16 , and the sealing tulip  13 . 
         [0035]    A channel  18  opens out into an upper region of the annular gap  19 . During CIP cleaning of the filling machine and its filling elements  3 , this channel  18  is used to feed a liquid cleaning and/or sterilization medium into the annular gap  19 . The liquid cleaning and/or sterilization medium then flows through this annular gap  19  over the entire axial length, cleaning and/or sterilizing the interior faces of the bellows  16  as it does so. 
         [0036]    As shown in  FIG. 2 , the channel  18  is configured so as to open out into the annular gap  19  obliquely, i.e. at an angle α of less than 90° relative to a plane E that is perpendicular to the filling element axis FA. During CIP cleaning and/or disinfection, this angle imparts, to the medium that flows out of the channel  18 , a velocity vector having a component in a peripheral direction of the outer face of tube-like housing section  6 . 1  or about the filling element axis FA. As a consequence of this velocity vector, the medium flows through the annular gap  19  from top to bottom in a spiral path. The combination of an adequately high flow velocity of the CIP cleaning and/or disinfection medium flowing along a spiral path thoroughly and optimally cleans and disinfects all interior faces, including those of the bellows  16 . The channel  18  can also be used to wash and/or pre-tension a container that is already present in the sealed position at the filling position. 
         [0037]    Adjoining the tube-like housing section  6 . 1  via a step  6 . 2  is an enlarged housing-section  6 . 3 . This enlarged housing-section  6 . 3  has an outer diameter that is larger than that of the tube-like housing section  6 . 1 . In order to attach the upper end of the bellows  16 , which is the end that lies furthest away from delivery orifice  8 , the bellows  16  are manufactured at that end in a single piece that incorporates a first annular bellows section  16 . 1 . 
         [0038]    An annular recess  20  formed on the step  6 . 2  accommodates the first annular bellows section  16 . 1 . A clamping ring  21  that encircles the filling element axis FA clamps the first annular bellows section  16 . 1  to this annular recess  20 . At its lower end, which lies nearest to the delivery orifice  8 , the bellows  16  have an integral second annular bellows section  16 . 2  that extends into the annular body  13 . 1 . The second annular bellows section  16 . 2  connects to a recess on the inner face of the annular body  13 . 1 . This connection is established in any of a variety of ways including, without limitation, gluing, clipping, clamping, vulcanizing, and screwing. Regardless of how it is made, the connection results in the inner face of the second bellows section  16 . 2  being flush or essentially flush with the contiguous inner face of annular body  13 . 1 . 
         [0039]    In order to fill a container  2  that is arranged with its container orifice beneath the filling element  3 , the sealing tulip  13  is first lowered along the filling element axis FA down onto the container  2  so that the inner ring seal  14  lies sealed against a container edge or an orifice edge  2 . 1  that surrounds the container&#39;s orifice. This centers the container  2  and places it in a sealed position on the filling element  3 . The controlled lowering of the sealing tulip  13  is effected, for example, in a cam-controlled manner by a cam follower  17 . 
         [0040]    The outer lip seal  15  is used, in the case of CIP cleaning for example, to seal a washing cap that is required for this purpose. 
         [0041]    Prior to the actual filling, the container  2 , which is in a sealed position on the filling element  3 , is pre-tensioned via the gas channel  12  using a pressurized inert gas, such as pressurized CO 2  gas. After pre-tensioning, the actual filling phase is initiated by opening the liquid valve  9 . As it flows into the container, the filling material displaces the inert gas out of container  2  through the gas channel  12 . 
         [0042]    The pre-tensioning and/or filling pressure acting on the inner annular surfaces of the sealing tulip  13  and of bellows  16  produces, for the sealing tulip  13 , a pressing force that cooperates with a pressing force exerted by the cam follower  17  to press the sealing tulip  13 , or its inner ring seal  14 , against the orifice edge  2 . 1 . The pressing force with which the sealing tulip  13 , or its inner ring seal  14 , lies against the orifice edge  2 . 1  can therefore be set by the pre-tensioning and/or filling pressure. 
         [0043]    The effective diameter of the bellows  16  that is relevant for the pressing force resulting from the pre-tensioning and/or filling pressure is dependent on the inner bellows diameter d i  and the larger outer bellows diameter d a  and corresponds to the root of (d i   e +d a   2 )/2). 
         [0044]    The previously customary guideway for the sealing tulip  13  on the tube-like housing section  6 . 1 , with a sliding seal, and its resulting disadvantages, are thus by configuring the filling element  3  with bellows  16 . 
         [0045]    With an existing filling machine which is already conceived for the use of conventional filling elements, and particularly when filling elements  3  are to be used instead of those conventional filling elements, it is expedient to set the effective diameter of the bellows  16  by an appropriate choice of the inner and outer bellows diameter d i  and d a  respectively in such a way that this effective diameter matches the slide diameter of the sliding seal that is used in conventional filling elements. 
         [0046]    The invention has been described hereinbefore by reference to one embodiment. Numerous variations as well as modifications are possible without departing from the inventive concept underlying the invention.