Patent Publication Number: US-2022219962-A1

Title: Machine and Method for Filling Containers With Liquid Contents

Description:
RELATED APPLICATIONS 
     This application is the national stage of international application PCT/EP2020/062014, filed on Apr. 30, 2020, which claims the benefit of the May 8, 2019 priority date of German application DE 102019111929.4, the content of which is incorporated herein by reference. 
     FIELD OF INVENTION 
     The invention relates to a filling machine for filling containers with liquid. 
     BACKGROUND 
     In many cases, it is desirable to fill a container with a beverage having dissolved gas, such as carbon dioxide or nitrogen gas. When doing so, there exists a risk of foaming. 
     To avoid the risk of foaming, it is often necessary to slow the filling speed. This, however, slows down production. 
     SUMMARY 
     The invention relates to container processing machines in the beverage industry, in particular to container-processing machines with capacities of more than 5,000 containers per hour, and in particular to container processing machines with a capacity of more than 20,000 containers per hour. In particular, the invention relates to container processing machines that are configured and arranged as what are referred to as filling machines or fillers, for the filling of containers with liquid, in particular with beverages. 
     An object of the invention is that of providing an improved filling machine and a correspondingly improved method for the filling of containers with liquid that allows in particular for a rapid filling of the container and carbonating of the liquid and that has a structure that is as simple as possible. 
     In one aspect, the invention features a filling machine for the filling of containers with liquid. The containers include bottles, other containers similar to bottles, or also cans, and specifically manufactured from different materials. Examples of liquids include beverages and liquid foodstuffs. 
     The filling machine comprises filling positions, each having a filling element. In this situation. Each filling element comprises a sealing element for sealing a mouth of the container. When the mouth of the container is sealed with the sealing element, there is then no connection between the container&#39;s interior and the ambient air or atmosphere surrounding the container. In particular, a negative pressure or an overpressure can then be built up in the container. Moreover, each filling element comprises a liquid channel, which can be closed by a filling valve, and a gas channel, which can be closed by a gas valve. With the filling valve open, the liquid channel is in fluid connection with the container&#39;s interior, and, with the gas valve open, the gas channel is likewise in fluid connection with the container&#39;s interior. In other words, both the liquid channel and the gas channel end in the space that is sealed by the sealing element. 
     According to the invention, the filling machine is configured so as to introduce carbon dioxide or nitrogen gas via the gas channel into the container before filling with liquid, and to produce a preload pressure in the container. The end of the gas channel facing away from the container is therefore connected preferably to a cylinder, a reservoir, or another source. The carbon dioxide or nitrogen gas present under preload pressure in the container in this situation is the quantity required for the carbonating or nitrogenating the liquid. Furthermore, the filling machine is configured so as to introduce the liquid into the container via the liquid channel under a filling pressure that exceeds the preload pressure. That is to say, the filling machine is configured so as to create a filling pressure that is greater than the preload pressure produced and built up in the container. This is necessary in order for the liquid to be introduced at all against the preload pressure in the container. As the liquid flow into the container, the carbon dioxide present in the container is then dissolved directly into the liquid, and the liquid is thereby carbonated. Since the mouth of the container is sealed by the sealing element, the carbon dioxide cannot escape from the container during the filling process. With a filling machine configured in this way, a rapid filling of the container can be achieved with simultaneous carbonating of the liquid during the filling. In addition to this, such a filling machine is of a relatively simple structure. 
     In some embodiments, the liquid introduced into the container is either uncarbonated or only lightly carbonated. With uncarbonated liquid, the complete carbonating of the liquid takes place at the filling of the container. If, conversely, the liquid is already partially carbonated, only a follow-up carbonating takes place at the filling of the container. In both cases, the liquid in the container then has the desired carbon dioxide content or degree of carbonation and the filling of the containers takes place rapidly and simply. 
     Also among the embodiments are those in which the preload pressure amounts to between 0.1 bar and six bar and those in which it is between two bar and five bar. A preload pressure of 0.5 bar corresponds to approximately one gram of carbon dioxide per liter, a preload pressure of five bar corresponds to approximately ten grams of carbon dioxide per liter, and preload pressures of two bar and four bar correspond, respectively, to approximately four grams and eight grams of carbon dioxide per liter. Accordingly, the preload pressures cited are suitable for producing beverages with the carbon dioxide content conventional in the beverage industry, which extends up to some eight grams of carbon dioxide per liter. 
     In other embodiments, each filling element comprises a vacuum channel, which can be closed by a vacuum valve, wherein, with the vacuum valve open, the vacuum channel is in fluid connection with the container&#39;s interior, i.e. the vacuum channel ends in the space sealed by the sealing element. The filling machine is in such an embodiment is configured so as to produce a negative pressure in the container&#39;s interior by way of the vacuum channel, and/or to reduce the pressure in the region of the mouth of the container. Such a vacuum channel can be used in many ways. First, before the carbon dioxide is introduced into the container under preload pressure, air, or residual air, can be removed from the container via the vacuum channel. The less air or oxygen is still present in the container, the better the carbonating of the liquid can take place. Depending on how little residual air is intended to be present in the container, after evacuation the container can be filled with carbon dioxide via the gas channel and then evacuated once again. If appropriate, these steps can be repeated several times. 
     A flushing of the container is also possible, in that carbon dioxide is introduced simultaneously via the gas channel into the container and the gas mixture present in the container is suctioned out via the vacuum channel. This also removes air or residual air from the container. 
     An alternative to the evacuating or flushing of the container is to convey a container already prefilled with carbon dioxide to the filling element. In this case it is possible to do without further flushing and therefore without the vacuum channel. 
     After the filling of the container with the liquid, the pressure in the region of the mouth of the container can be adjusted to a specific value, and, if appropriate, can be relaxed at a later time to atmospheric pressure. In order to reduce the pressure, in this situation the vacuum valve is opened, so that surplus gas can escape from the region of the mouth of the container. The relaxing to atmospheric pressure can also take place by way of a further connection to the outside. 
     In some embodiments, the filling element comprises a pressure sensor, which is configured so as to measure the pressure in the container&#39;s interior and/or in the region of the mouth of the container. Based on the measured value from this pressure sensor, the gas valve and/or the vacuum valve can be controlled in such a way that a desired pressure exists in the container&#39;s interior or, respectively, in the region of the mouth of the container. This is of great significance for the preload pressure since the preload pressure determines the quantity of carbon dioxide that is dissolved in the liquid and therefore represents an important feature of the finished product. 
     In some embodiments, the sealing element is adjacent to a protection space. This protection space accordingly borders on the mouth of the container and is fluid communication with the container&#39;s interior. The container&#39;s interior and the protection space are however sealed against the surrounding environment. Furthermore, the liquid channel and the gas channel open into the protection space. Furthermore, each filling position comprises a closure device, wherein the closure device is configured such as to close the mouth of the container in the protection space with a closure. In this situation, the closure is, for example, a crown cork, a screw closure, or the cover of a beverage can. The container is closed in the protection space by the closure device. As a result, if this is not yet the case, the pressure in the protection space is adjusted to a value above the saturation pressure of the carbon dioxide in the liquid. Due to the fact that the container is closed immediately after the filling in the protection space, a particularly rapid filling and processing of the container is possible. 
     Also among the embodiments are those in which the filling positions are arranged on a circulating transport element, or rotor. By means of an inlet star, the containers are then taken over from the transport element, and, by means of an outlet star, the filled containers are then transferred to the container processing machine following downstream. In this way, a rapid following and processing of the containers can take place, without the containers having to be stopped in the interim. 
     In another aspect, the invention features a method for the filling of containers with liquid, the container being bottles, other bottle-like containers, or also cans. The liquid is either a beverage or a liquid foodstuff. The filling of the containers takes place by means of a filling machine in accordance with the foregoing description. In particular, the filling machine comprises a plurality of filling positions, wherein each filling position comprises a filling element. A mouth of the container is sealed with a sealing element of the filling element, such that the container&#39;s interior is no longer in contact with the ambient air. For the filling of the container, a filling valve that closes a liquid channel is opened, such that liquid is introduced into the container via the liquid channel under a filling pressure. 
     According to the invention, after the sealing of the mouth of the container and before the introduction of the liquid, a gas valve that closes the gas channel is opened. An end of the gas channel facing away from the container is in this situation connected to a carbon dioxide cylinder, a carbon dioxide reservoir, or another carbon dioxide source, such that, at the opening of the gas valve, and before the filling with the liquid, carbon dioxide is introduced into the container, and a preload pressure is produced in the container. The carbon dioxide present in the container under preload pressure has the quantity required for the carbonating of the liquid. Next, the liquid is introduced into the container under a pressure that exceeds the preload pressure. In order to be able then to introduce the liquid into the container against the preload pressure, the filling pressure is particularly advantageously selected as greater than the preload pressure. With this method a rapid filling of the container can be achieved, with the simultaneous carbonating of the liquid. 
     In some practices, the container preloaded with carbon dioxide is filled with liquid that is uncarbonated or only partially carbonated. With non-carbonated liquid, the complete carbonating of the liquid during the filling of the container takes place during the filling of the container. Conversely, if the liquid is already partially carbonated, then, during the filling of the container, only follow-up carbonating takes place. In both cases, the liquid in the container then exhibits the required carbon dioxide content or degree of carbonating, and the filling of the container takes place rapidly and simply. 
     Advantageously, at the introduction of the liquid into the container, the carbon dioxide present in the container is immediately dissolved in the liquid, and thereby the liquid is at least partially carbonated. Due to the fact that the mouth of the container is sealed, the carbon dioxide also cannot escape from the container. This therefore results in a rapid carbonating of the liquid. 
     It is also of advantage if the pressure pertaining in the container&#39;s interior and/or in the region of the mouth of the container is measured by means of a pressure sensor. 
     The gas valve, and any other valves that allow for a gas inflow or outflow into and out of the space enclosed by the sealing element, are then controlled as a dependency of the measured values from the pressure sensor in such a way that the desired pressure pertains in the container&#39;s interior and in the region of the mouth of the container respectively. This is of great significance for the preload pressure in particular, since the preload pressure determines the quantity of carbon dioxide that is dissolved in the liquid, and it therefore represents an important feature of the finished product. 
     It is also advantageous if, before the introduction of the carbon dioxide under preload pressure into the container, the container is first evacuated via a vacuum channel. Any air or residual air still in the container is therefore removed from the container, which improves the carbonating of the liquid. Depending on how little residual air should be present in the container, after the evacuation via the gas channel the container can then be filled with carbon dioxide and then evacuated once again. These steps can be repeated several times if appropriate. As an alternative or in addition to the evacuation of the container, the container can be flushed with carbon dioxide. For this purpose carbon dioxide is simultaneously introduced into the container via the gas channel, and the gas mixture present in the container is sucked out via the vacuum channel. This also removes air or residual air from the container. 
     In a particularly advantageous variant of the method, a closure cover is applied in a protection space, which is adjacent to the sealing element. The closure cover is in this case, for example, a crown cork, a screw closure, or the lid of a beverage can. The protection space is adjacent to the mouth of the container, and is in fluid contact with the container&#39;s interior. The container&#39;s interior and the protection space are, however, sealed against their surroundings. After the introduction of the liquid into the container, a pressure is preferably set in the region of the mouth of the container that lies above the saturation pressure of the carbon dioxide of the liquid present in the container. In this situation it is entirely possible for the pressure prevailing in the region of the mouth of the container, after the filling of the container with the liquid, will already exhibit the desired value. Accordingly, the mouth of the container will be closed with the closure cover. Since the closure of the container can take place immediately after the filling of the container, this method is particularly rapid. After the closing of the container, the mouth of the container is released from the sealing element and the container is transported onwards or transferred to the container processing machine following downstream. 
     In another advantageous variant of the method, after the introduction of the liquid a pressure is preferably set in the region of the mouth of the container that is approximately equal to the saturation pressure of the carbon dioxide of the liquid present in the container. At this pressure, the liquid present in the container undergoes stirring for a predetermined period of time. Due to the pressure that is approximately equal to the saturation pressure of the carbon dioxide of the liquid present in the container, it will be ensured that, during the stirring of the liquid, no carbon dioxide escapes from the liquid, while on the other hand no further carbon dioxide will be absorbed by the fluid. After the stirring of the liquid has been carried out, the pressure in the region of the mouth of the container is relaxed to atmospheric pressure, and the container is transported to a closure device. Since a specific period of time must be allowed for the stirring of the liquid, this method is slower than that presented previously. The filling machine is easier to construct, however, since a filling device that closes the container in the protection space can be omitted. 
     In another aspect, the invention features a filling machine that fills containers with liquid, the filling machine comprising filling positions, each of which comprises a filling element, wherein each of the filling elements comprises a seal that seals a container&#39;s mouth, a filling valve, a gas valve, a liquid channel that, when the filling valve is opened, is in fluid communication with the container&#39;s interior, and a gas channel that, when the gas valve is open, is in fluid communication with the container&#39;s interior, wherein the filling machine is configured to introduce an inert gas into the container&#39;s interior via the gas channel to create a preload pressure in the container such that the inert gas in the container dissolves in the liquid, wherein the filling machine is further configured to introduce a volume of liquid into the container&#39;s interior through the liquid channel at a filling pressure that exceeds the preload pressure. 
     Embodiments include those in which the inert gas is either nitrogen gas and carbon-dioxide gas. 
     Further embodiments, advantages, and possible applications of the invention also derive from the following description of exemplary embodiments and from the Figures. In this context, all the features described and/or represented in the images are in principle the object of the invention, alone or in any desired combination, regardless of their arrangement in the claims or reference to them. The contents of the claims are also made a constituent part of the description. 
     Although some aspects have been described in connection with a device, it is understood that these aspects also represent a description of the corresponding method, such that a block element or structural element of a device is also to be understood as a corresponding method step or as a feature of a method step. By analogy with this, aspects that have been described in connection with, or as, a method step also represent a description of a corresponding block or detail or feature of a corresponding device. Some or all of the method steps can be carried out by a hardware apparatus (or with the use of a hardware apparatus), such as, for example, a microprocessor, a programmable computer, or an electronic circuit. With some exemplary embodiments, some or many of the most important method steps can be carried out by such an apparatus. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is described in greater detail hereinafter on the basis of the Figures in respect of exemplary embodiments. The Figures show, by way of example: 
         FIG. 1  shows a view from above a filling machine, 
         FIG. 2  shows a section through one of the filling elements shown in  FIG. 1 , and 
         FIG. 3  shows a side view of an alternative filling element. 
     
    
    
     Identical reference numbers are used in the Figures for elements of the invention that are the same or have the same effect. In addition, for the sake of easier overview, only reference numbers are represented in the Figures that are required for the description of the respective Figure. 
     DETAILED DESCRIPTION 
       FIG. 1  shows a filling machine  1  having a rotor  2  that rotates about a vertical axis “A”. The rotor&#39;s circumference has filling positions  2 , each of which comprises a filling element  4 . During operation, an inlet star  6  provides the rotor  2  with containers  5  that are to be filled. The rotor  2  moves the containers  5  in a transport direction as it fills them. It then transfers the filled containers  5  to an outlet star  7  that conveys them on for further processing. 
       FIG. 2  shows one of the filling elements  4  engaged with a container  5  that is to be filled. Although the container  5  shown herein is a bottle, other containers, such as cans, can also be filled. 
     The filling element&#39;s underside features a seal  8  that seals the container&#39;s mouth  5 . 1 , thereby isolating the container&#39;s interior  5 . 2  from ambient air surrounding the container  5 . In the illustrated embodiments, the seal  8  is a ring seal. 
     The filling element  4  further comprises a liquid channel  9 , a gas channel  10 , and a vacuum channel  11 , each of which is in fluid communication with the container&#39;s interior  5 . 2 . The filling element  4  also includes a filling valve  12  that closes the liquid channel  9 , a gas valve  13  that closes the gas channel  10 , and a vacuum valve  14  for closing the vacuum channel  11 . 
     Once the mouth  5 . 1  has been sealed at the seal  8 , an evacuation step is carried out by opening the vacuum valve  14  opens to evacuate air from the container&#39;s interior  5 . 2  and closing it shortly thereafter. 
     In some cases, the vacuum is strong enough to evacuate nearly all the ambient air, in which case filling can commence thereafter. In other cases, too much residual air remains. Under these circumstances, a gas-insertion step is carried out by opening the gas valve  13  for a specific period of time, thereby allowing an inert gas from a gas source to flow through the gas channel  10  and into the container&#39;s interior  5 . 2 . This fills the container&#39;s interior  5 . 2  with a mixture of mostly inert gas with some residual air. The foregoing is then evacuation step is then repeated. This gas-insertion step is then followed by another evacuation step. These steps are as often as needed to attain a sufficiently low concentration of ambient air in the container&#39;s interior  5 . 2 . 
     An alternative embodiment replaces the evacuation step with a flushing step, in which the container&#39;s interior  5 . 2  is flushed with inert gas. This is carried out by opening the gas valve  13  and vacuum valve  14  concurrently so that inert gas flows into the container  5  as a mixture of air and carbon dioxide is sucked out of the container, with the ratio of air in the mixture progressively decreasing. 
     Another embodiment avoids the foregoing steps by providing a container  5  already filled with inert gas to the filling element  4 , thereby obviating the need for the vacuum channel  11  and the vacuum valve  14 . 
     To prepare the container  5  for filling, the container is filled, via the gas channel  10 , with enough inert gas to achieve a predetermined preload pressure in the container&#39;s interior  5 . 2 . This preload pressure is high enough to cause the inert gas to dissolve in the liquid as the liquid fills the container  5 . In a preferred embodiment, inert gas in the container  5  dissolves immediately as the liquid flows into the container  5 . 
     Preferably, the liquid enters the container  5  with no dissolved inert gas or only a small amount of dissolved inert gas. The quantity of inert gas present in the container  5  is the difference between the amount of inert gas already dissolved, if any, and the desired amount of dissolved inert gas. For the case in which the inert gas is carbon dioxide, a preload pressure of one bar corresponds to approximately two grams of dissolved carbon dioxide per liter. To carbonate a completely uncarbonated liquid to achieve the typical value of eight grams per liter, the preload pressure is approximately four bar. 
     In some embodiments, a pressure sensor measures pressure in the container&#39;s interior  5 . 2 . The resulting measurement provides a basis for controlling the gas valve  13  to attain the desired preload pressure in the container&#39;s interior  5 . 2 . In other embodiments, different methods for attaining the desired preload pressure are used. 
     Upon reaching the desired preload pressure, the gas valve  13  closes and the filling valve  12  opens. This permits the liquid to flow through the liquid channel  9  from a reservoir into the container  5 . Since the container&#39;s interior  5 . 2  has been pressurized to a preload pressure, it is necessary to pressurize the liquid with a filling pressure that exceeds the preload pressure. 
     When the desired volume of liquid has entered the container  5 , the filling valve  12  closes. Attainment of the desired liquid volume can be determined based on a predetermined filling time or based on a measurement from a flowmeter or a filling-level probe. 
     Upon completion of filling, the head space at the container&#39;s mouth  5 . 1  is pressurized to the liquid&#39;s saturation pressure. At this point, the inert gas will have been dissolved into the liquid. 
     The pressurization step is carried out by measuring the pressure with a pressure sensor and either introducing additional inert gas via the gas channel  10  or removing inert gas via the vacuum channel  11 . With the pressure having been thus set, stirring of the liquid present in the container  5  takes place over a predetermined period of time, after which the vacuum valve  14  is then opened and the pressure in the container&#39;s interior  5 . 2  is relaxed to atmospheric pressure. 
     The container  5  is next drawn downwards, thereby breaking the seal between the seal  8  and the container&#39;s mouth  5 . 1 . The container is then transported to a closing machine that closes the container  5 . 
       FIG. 3  shows a further embodiment of a filling element  4  that features a closure device  15  that closes the container  5  with a closure  16 , which in the illustrated embodiment is a crown cork. 
     The container  5  to be filled is first introduced from below into a cut-out opening of the filling element  4 . The seal  8 , which is again a ring seal, then surrounds the container  5  from the outside such that the cut-out opening in the filling element  4  forms a protection space  17  that isolates various components from the from the surrounding environment. These include the container&#39;s mouth  5 . 1 , an end of the liquid channel  9 , an end of the gas channel  10 , an end of the vacuum channel, which is not visible in  FIG. 3 , and the closure  16 . 
     The evacuation, flushing, and pressure preloading of the container  5  are carried out in the same manner as that described in connection with  FIG. 2 . 
     In the illustrated embodiment, the end of the liquid channel  9  opens onto a side of the protection space  17 . The liquid thus has to make a turn to enter the container  5 . An angled connecting-channel  16  enables this turn to be carried out. 
     A thruster  18  pushes the angled connecting channel  16  sideways into the protection space  17  towards the opening of the liquid channel  8 . The thruster  18  pushes the connecting channel  16  into the protection space  17  in such a way that one end of the connecting channel  19  connects to the end of the liquid channel  9  and the other end of the connecting channel  19  comes to lie directly above the container&#39;s mouth  5 . 1 , thereby ensuring reliable filling of liquid into the container  5 . 
     After the filling of the liquid into the container  5 , the thrust element  18  and the connecting channel  19  are retracted. If necessary, the pressure in the protection space  17  is adjusted to a pressure that is above the saturation pressure of the liquid that is now in the container  5 . 
     In embodiment shown in  FIG. 3 , it is possible to avoid the waiting time that arises from having to stir the liquid in the container  5 . This is carried out by closing the container  5  at the pressure prevailing in the protection space  17 . The embodiment shown in  FIG. 3  thus promotes more rapid filling. 
     The closure  16 , which was previously into the protection space  17 , is held over the container&#39;s mouth  5 . 1 . A counter-holder  20  presses the cover  16  onto the container&#39;s mouth  5 . 1 . A pull ring  21 , which is arranged concentrically around the counter-holder  20 , then draws the sides of the crown cork  16  over the container&#39;s mouth  5 . 1 , thereby closing the container  5 . 
     After removing the seal  8  from the container  5 , the container  5  is drawn downwards out of the protection space  17  and then transported onwards for further processing. 
     The invention has been described heretofore by way of exemplary embodiments. It is understood that a large number of modifications or derivations are possible without thereby departing from the scope of protection of the invention defined by the claims. 
     In particular, inert gases other than carbon dioxide can be used. For example, some embodiments uses nitrogen gas as an inert gas, in which case nitrogen rather than carbon dioxide is dissolved in the liquid.