DE20110362U1 - Filling tube-less filling element for a filling machine for low-oxygen filling of a drink - Google Patents

Description

Filling tube-less filling element for a filling machine for low-oxygen filling of a beverage, in particular beer, into bottles and filling machine with such

Filling elements

The innovation relates to a filling element according to the generic term of claim 1 and to a filling machine according to the generic term of claim 14.

Plastic bottles, i.e. PET bottles, are increasingly being used in the beverage industry. The market launch of such bottles for beverages such as beer, which require low-oxygen bottling for reasons of shelf life, is imminent, although the filling processes previously used for bottling beer are fundamentally unsuitable for this.

The filling process currently most commonly used for filling beer, in which the interior of the bottle is pre-evacuated at least once and then flushed with an inert gas, namely CO ₂ gas, cannot be used when using plastic bottles because they have relatively low resistance to negative pressure and implode at a low negative pressure, for example at a negative pressure of only 200 to 300 mbar. If the wall thickness of such PET bottles is reduced even further to save material, e.g. for cost and environmental reasons, which is to be expected in the future, this will lead to a further reduction in the vacuum resistance of such PET bottles.

With conventional multiple pre-evacuation followed by rinsing, CO ₂ atmospheres of over 99% CO ₂ are currently easily achieved when filling glass bottles. Under these conditions, the oxygen absorption in the beverage during filling is less than 0.03 mg/l. However, for the shelf life of oxygen-sensitive beverages such as beer, it is essential that these values are not exceeded even when filling plastic bottles.

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This is also true in view of the fact that with the plastic materials that can be used for bottles today from an economic point of view, a limited diffusion of oxygen through the bottle wall is unavoidable. The exposure of oxygen-sensitive drinks to additional oxygen from the production process and in particular from the filling process must therefore be reduced to an absolute minimum.

The aim of the innovation is to demonstrate a filling element which enables low-oxygen filling of beverages, in particular beer, in both glass and plastic bottles, with the oxygen load during the filling process which is particularly required when filling beer or other oxygen-sensitive beverages and which is reduced to a minimum.

To solve this problem, a filling element according to claim 1 and a filling machine having a plurality of such filling elements are designed according to claim 14.

The new filling element enables filling of filling products in either glass or plastic bottles based on the filling level. This filling system based on the filling level has the advantage over the volumetric filling system for both glass and plastic bottles that, with filling based on the filling level, fluctuations in the empty volume of the bottles, which can be seen in particular in reusable bottles, do not lead to different filling levels, which could give the consumer the impression of inferior quality.

Another important aspect of filling level-controlled filling is that, especially when filling beer or other beverages containing CCy, it is possible to remove the harmful oxygen in the bottle neck not occupied by the filling product by means of a final high-pressure injection and the foaming produced by this.

bottle neck, which is particularly important for plastic bottles. In order to achieve reproducible foaming results and a low oxygen content in the bottle neck, uniform filling levels are essential. From this point of view, the filling level-controlled filling system is an essential feature of this innovation.

The new filling element makes it possible to fill oxygen-sensitive drinks, particularly beer, with low oxygen levels in plastic bottles or PET bottles. In particular, the new design also makes it possible to switch the filling machine from filling glass bottles to filling plastic bottles (PET bottles) and vice versa by simply selecting the program, i.e. with a mouse click, without any "hardware" changes to the filling machine or the filling elements being necessary.

The innovation is characterized by a high degree of flexibility with the greatest possible filling convenience and thus also makes an investment decision easier for the user, since the filling element or filling machine according to the innovation enables the filling of oxygen-sensitive beverages, in particular beer, with the same quality and with a particularly low consumption of inert gas (CCyGas), which is particularly advantageous for economic reasons and for reasons of environmental protection.

When using plastic bottles, the interior of these bottles is flushed with the flushing gas before the actual pre-pressurization and filling. This gas is blown into the bottle via the probe that determines the filling level and is designed as a flushing pipe and is sucked out of the bottle at the bottle mouth using the vacuum. The parameters are set so that the pressure in the bottle is approximately equal to atmospheric pressure, but under no circumstances does it reach a critical negative pressure that could pose a risk of the plastic bottle imploding.

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The probe which determines the filling level and is designed as a flushing pipe is of such a length that its probe end extends relatively far into the respective bottle or bottle neck and at a sufficient distance from the bottle mouth.

Further developments of the innovation are the subject of the subclaims. The innovation is explained in more detail below using the figures and exemplary embodiments. They show:

Fig. 1 shows a simplified representation of a filling element without a filling tube of a filling machine of a rotating design for the low-oxygen filling of beverages, in particular beer, optionally in bottles made of glass or plastic (e.g. PET bottles), together with a bottle attached to the filling element and with a partial representation of a rotor and a partially filled ring bowl of the filling machine;

Fig. 2 shows an enlarged partial view of the filling element of Figure 1 in the region of its dispensing opening and in the region of the mouth of the bottle;

Fig. 3 shows an enlarged partial view of a probe designed as a flushing pipe, which determines the filling level, in the region of an upper end of the flushing pipe channel formed in this probe;

Fig. 4 shows a further embodiment of the probe determining the filling level in individual view and in section.

The filling element, generally designated 1 in the figures, is part of a filling machine of rotating design and is provided together with a large number of similar filling elements 1 distributed at equal angular intervals around a vertical machine axis on the circumference of a rotor 2. In the embodiment shown, a first ring channel 3 and a second ring channel 4 are formed in this rotor 2. Of these ring channels, which are provided jointly for all filling elements 1 of the filling machine, the ring channel 3 serves as a vacuum channel and the ring channel 4 as a return gas and pressurized gas channel. For this purpose, the ring channel 3 is connected to a negative pressure or vacuum source (not shown) and the

Ring channel 4 is connected to a device which supplies an inert purge gas, preferably CO ₂ purge gas under pressure.

Furthermore, a ring tank 5 common to all filling elements 1 is provided on the rotor 2, the interior 6 of which is partially filled with the liquid filling material (beverage) up to a level N in a level-controlled manner, so that a gas space 6" is formed above the level of the liquid level of the liquid space 6'. The liquid space 6' is connected to a supply line for supplying the filling material under pressure and the gas space 6" is connected to a line for supplying the inert gas (CO ₂ gas) occupying this gas space under pre-pressure.

Each filling element 1 is assigned a bottle carrier 7, with which the bottle 8 to be filled is pressed and held with its bottle mouth 8' in a sealed position against an annular seal 9, which is provided on the underside of the filling element housing 10 of the respective filling element 1 and encloses an annular discharge opening 11 for the filling material. In the filling element housing 10, among other things, a liquid channel 12 is formed, which is connected to the liquid space 6' of the ring bowl 6 via a feed 13. In the liquid channel 12, the lower end of which forms the discharge opening 11, the liquid valve 14 is also provided in a known manner for the controlled introduction and termination of the flow of filling material into the respective bottle 8.

As shown in particular in Figure 2, the liquid valve 14 consists essentially of the valve body 15, which is provided on the outer surface of a return gas pipe 16 arranged coaxially with a vertical filling element axis FA. This return gas pipe 16 can be moved axially in the direction of the filling element axis FA by a predetermined stroke to open and close the liquid valve 14, namely by an actuating device 17, which is essentially formed by a pneumatic piston and a spring and can be individually controlled for each filling element 1 by the electronic control of the filling machine (not shown) and via pneumatic control valves (also not shown).

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The fluid valve 14 also has a valve seat 18 which interacts with the valve body 15 and is formed in the fluid channel 12.

A filling level-determining probe 19 is provided on the same axis as the return gas pipe 16, which ends approximately in the area of the ring seal and protrudes with a predetermined length from the discharge opening 11 over the underside of the filling element housing 10. An annular return gas channel 16' is formed between the outer surface of the probe 1 and the inner surface of the return gas pipe 16, which is open at its lower end in the area of the discharge opening 11 and opens with its upper end into a gas space 20 formed in the filling element housing 10.

The probe 19, which is guided through the gas space 20, is designed as a flushing pipe with a probe channel 19', which is open at the lower probe end 19" of the probe 19. The probe channel 19', which is closed at the upper end of the probe 19, opens there into a gas space 22 via a radial opening 21.

In the embodiment shown, the tubular probe 19 is designed in three layers and consists of an outer layer 23 made of electrically conductive material, for example a corrosion-resistant metal, the middle layer 24 made of an electrically insulating material, for example a suitable plastic or ceramic material, and the inner layer 25 made of the electrically conductive material, for example the corrosion-resistant metal.

As Figure 2 shows, the layers 23 - 25 end at different distances from the lower, free end of the probe 19, i.e. the layer 25 forms the probe end 19" with its lower end. The layer 24 ends at a first distance from the lower end of the probe 19 and the layer 24 at a larger second distance from this lower end, whereby the lower end of the layer 23 corresponds to the filling level FH aimed for when filling the bottles 8 or, in the case of time-controlled refilling, is slightly lower than the filling level FH aimed for when filling. Otherwise, the layers 23 - 25 extend over the entire length of the probe 19. Above

of the gas chamber 22, the probe 19 is held on the filling element housing 10 so that it can be adjusted in height in steps in the direction of its axis (double arrow A), for example, in order to be able to set different filling heights FH, for example. The gas chamber 22 has an axial length which is at least equal to the maximum adjustment stroke A for the probe 19, so that with each adjustment of the probe 19, the probe channel 19' opens into the gas chamber 22 via the opening 21.

An upper rod-shaped section 25' of the probe 19, which is electrically connected to the inner layer 25, is connected to an input of the control system of the filling machine which monitors the filling level, so that this input is at the ground potential of the filling machine when the filling material level has reached the lower end of the outer layer 23 during filling.

The probe 19 has a further axial opening 26 on its partial length projecting downwards beyond the discharge opening 11 and at a distance above the lower end of the layer 23, in particular also for filling material level compensation within the probe channel 19' at the end of the respective filling phase and for emptying the probe channel 19' when pulling or removing the filled bottle 8 from the respective filling element 1.

Three individually controllable and pneumatically actuated control cylinders or control valves 27, 28 and 29 are provided on the filling element housing 10, of which the control valve 27 is assigned to the gas chamber 6" and can therefore also be referred to as a clamping gas valve, the control valve 28 is assigned to the channel 3 serving as a vacuum channel and can therefore also be referred to as a vacuum control valve, and the control valve 29 is assigned to the ring channel 4 serving as a return gas and purge gas channel and can therefore also be referred to as a return gas and purge gas valve.

In the filling element housing 10, various gas paths are also formed, which contain these control valves 27 - 29, namely:

Gas path 30, which has the control valve 27 and which connects the gas chamber 6" with the gas chamber 20;

Gas path 31, which contains the control valve 28 and connects the annular channel 3 (vacuum channel) with the gas space 20;

Gas path 32, which contains the control valve 29 and connects the ring channel (return gas and purge gas channel) with the gas chamber 22.

Furthermore, a gas path 33 is provided which connects the part of the gas path 30 or 31 leading directly to the gas chamber 20 with the part of the gas path 32 which is directly connected to the ring channel 4 and in which a throttle 34 and, in series with this, a check valve 35 are provided which opens for a gas flow from the gas path 30 or 31 into the gas path 32, in particular for filling with a slowed filling speed at the beginning and possibly also at the end of the respective filling phase, and which blocks a gas flow in the opposite direction.

The filling machine equipped with several filling elements 1 enables bottles 8 made of glass to be filled with a carbonated filling material, for example beer, under counter pressure using the usual process steps, in particular with a single or multiple pre-evacuation of the interior of the bottle 8 in a sealed position with the filling element 1 by opening the control valve 28 via the return gas channel 16' and with a subsequent flushing of the interior of the bottle 8, for example by additionally opening the control valve 28 with flushing gas from the ring channel A ₁ , namely via the probe channel 19', whereby the flushing gas is discharged from the interior of the bottle via the return gas channel 16' into the ring channel 3. Then the interior of the bottle 8 is pre-tensioned by opening the control valve 27, the subsequent slow filling of the pre-tensioned bottle 8 by opening the liquid valve 14 with the control valves 27 - 29 closed and the rapid filling by opening the control valve 27, whereby after reaching the filling level the pre-relief and relief of the filled bottle 8 takes place with the liquid valve 14 closed, namely by appropriate

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Control of the control valve 29 and by lowering the bottle 8 from the filling element 1.

The filling machine provided with the filling elements 1 also allows a filling level-controlled, low-oxygen filling of beverages, and in particular carbonated beverages, into plastic or PET bottles with a low consumption of inert or CO ₂ gas, simply by selecting a different program sequence on the electronic control device of the filling machine. For this purpose, prior to the actual pre-pressurization and filling phase, the interior of these bottles is again effectively flushed via the channel 19' of the probe 19, namely from the ring channel 4 by opening the control valves 28 and 29, so that the flushing gas from the ring channel 4 is blown into the gas chamber 22 via the opened control valve 29 and from there into this bottle via the probe channel 19' of the probe 19, whose lower end 19" extends relatively far into the interior of the bottle 8, and in the process also reaches the bottom of the bottle, with the flushing gas being discharged via the return gas channel 16' and the opened control valve 28 into the ring channel 3.

The parameters, and in particular the flow cross sections for supplying the purge gas into the interior of the bottle 8 and for removing the purge gas from the interior of the bottle 8 are selected, taking into account the pressures in the ring channels 4 and 3, so that a negative pressure compared to the atmosphere does not arise in the bottle 8 to be purged, or at least a critical negative pressure does not occur at which the bottle 8 made of PET could implode. The interior of the bottle 8 is preferably kept at approximately atmospheric pressure during purging.

Figure 4 shows a simplified representation and in section of another possible embodiment of the filling level determining probe 19a designed as a flushing pipe. This is again essentially designed in three layers, i.e. it consists of the outer layer 23a formed by a thin tube made of electrically conductive material, for example metal, the insulating layer 24a and the inner,

electrically conductive layer 25a, which is formed by a tube-like probe body made of metal, the wall thickness of which is significantly greater than the wall thickness of layers 23a and 24a. Layer 24a is formed by a coating of the electrically insulating material, preferably a HALAR coating. The tube forming the outer layer 23a is pressed or hammered onto layer 24a in such a way that a tight, in particular gas-tight transition is created between the two layers 23a and 24a. Otherwise, probe 19a corresponds in its further design and function to probe 19.

The innovation has been described above using exemplary embodiments. It is understood that changes and modifications are possible without thereby departing from the inventive concept underlying the innovation.

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List of reference symbols Filling element 1 rotor 2 Ring channel 3.4 Ring boiler 5 Ring boiler interior 6 Fluid space 6' Gas room 6" Bottle carrier 7 Bottle 8th Bottle mouth 8th' Ring seal 9 Filling element housing 10 Filling material dispensing opening 11 Fluid channel 12 Feeding 13 Fluid valve 14 Valve body 15 Return gas pipe 16 Return gas channel 16' Actuator for liquid valve 17 Valve seat 18 Probe for level-controlled filling 19, 19a Probe or flushing channel 19' Gas room 20 opening 21 Gas room 22 layer 23-24 layer 23a-24a

25' Probe section 26 opening 27, 28, 29 Control valve 30,31,32,33 Gas path 34 throttle 35 check valve A Adjustment stroke FA Filling element axis FH Filling height

Claims (14)

1. Filling element without a filling tube for a filling machine for low-oxygen filling of a beverage, in particular beer, into bottles ( 8 ), with a liquid channel ( 12 ) having a controllable liquid valve ( 14 ) and ending in a filling material discharge opening ( 11 ) on an underside of a filling element housing ( 10 ), with a return gas channel ( 16 ') which is open in the area of the filling material discharge opening ( 11 ) and, when the bottle ( 8 ) is attached to the filling element ( 1 ), opens into the interior of this bottle in the same way as the filling material discharge opening ( 11 ), with a probe ( 19 , 19a ) which determines the filling level and which projects over the filling material discharge opening ( 11 ) over the underside of the filling element housing ( 10 ) and, when the bottle ( 8 ) is attached to the filling element, extends into it, with controlled gas paths ( 30 , 31 , 32 ), which at least partially contain control valves ( 27 , 28 , 29 ) and via which the return gas channel ( 16 ') can be connected in a controlled manner to at least one vacuum channel ( 3 ), characterized in that the probe ( 19 , 19a ) determining the filling level is designed as a flushing pipe with a flushing pipe or probe channel ( 19 ') which is open at the lower, free probe end ( 19 ") and can be connected to a flushing gas channel ( 4 ) via a gas path ( 32 ) having a control valve ( 29 ). 2. Filling element according to claim 1, characterized in that the probe ( 19 , 19a ) forms at least two probe contacts ( 23 , 25 ) which are electrically separated from one another on the probe body and offset from one another in the longitudinal direction of the probe. 3. Filling element according to claim 2, characterized in that the probe ( 19 , 19a ) is formed by a multi-layered or multi-layered tubular probe body which has at least a first layer ( 23 , 23a ) which consists of an electrically conductive material, preferably of a metal, and is exposed at least at the lower free end of the probe ( 19 , 19a ), a second layer ( 24 , 24a ) made of an electrically insulating material adjoining this first layer ( 23 , 23a ) towards the probe axis, and a third layer ( 25 , 25a ) made of electrically conductive material adjoining this second layer ( 24 , 24a ) in the direction of the probe axis, the third layer (25) being exposed at least in the region of the probe end ( 19 "). 4. Filling element according to claim 3, characterized in that the third layer ( 25 , 25a ) forms the probe end ( 19 ") and the second layer ( 24 , 24a ) ends at a first distance from the probe end ( 19 ") and the first layer ends at a second distance from the probe end ( 19 "), and that the second distance is greater than the first distance. 5. Filling element according to one of the preceding claims, characterized in that the probe channel ( 19 ') is axially closed at the end of the probe body remote from the probe tip and is connected via at least one radial opening ( 21 ) to the controlled gas path ( 32 ) leading to the purge gas channel ( 4 ) or to a gas space ( 22 ) connected to this gas path ( 32 ). 6. Filling element according to claim 5, characterized in that the probe ( 19 , 19a ) is provided on the filling element housing ( 10 ) so as to be axially adjustable in the axial direction by a predetermined adjustment stroke (A), and that the first gas space ( 22 ) has a length in the axial direction of the probe ( 19 , 19a ) which is at least equal to the adjustment stroke (A). 7. Filling element according to one of the preceding claims, characterized in that the probe ( 19 , 19a ) is guided through a second gas space ( 20 ) into which the return gas channel ( 16 ') opens and which is connected to the first, controllable gas path ( 31 ). 8. Filling element according to one of the preceding claims, characterized in that the probe ( 19 , 19a ) has at least one further radial opening ( 26 ) at a distance above the probe end ( 19 ") and also at a distance above the lower end of the outer layer ( 23 , 23a ). 9. Filling element according to claim 8, characterized in that the at least one further radial opening ( 26 ) has a flow cross-section which is smaller than the flow cross-section of the probe channel ( 19 '). 10. Filling element according to one of the preceding claims, characterized in that in addition to the first and second gas paths ( 31 , 32 ), a third gas path is provided, which can also be controlled by at least one control valve ( 27 ), via which the return gas channel ( 16 ') can be connected in a controlled manner to a channel or gas space ( 6 ') containing a pre-pressurizing gas, and that a fourth gas path is provided which connects the return gas channel ( 16 ') or a part of the first or third gas path ( 31 , 30 ) which is constantly connected to this return gas channel ( 16 ') with the purge gas channel ( 4 ) or a part of the second gas path ( 32 ) which is directly connected to this purge gas channel, and that in the fourth gas path a throttle ( 34 ) forming a reduced flow cross-section and a check valve ( 35 ) are provided which are designed for a flow from the second gas path into the first or third gas path and opens it for flow in the opposite direction. 11. Filling element according to one of the preceding claims, characterized in that the control valves ( 27 , 28 , 29 ) are pneumatically actuated valves or pneumatic cylinders. 12. Filling element according to one of the preceding claims, characterized in that the third layer ( 25 a) is formed by a tubular probe body made of electrically conductive material, preferably metal, the second layer ( 24 a) by a coating of the tubular probe body on its outer surface with an electrically insulating material, for example plastic, and the first layer ( 23 a) by a tube made of electrically conductive material, preferably metal, which preferably has a reduced wall thickness compared to the probe body and is applied to the coating and fastened there in a gas-tight manner. 13. Filling element according to claim 12, characterized in that the tube forming the first layer ( 23a ) is attached to the coating forming the second layer ( 24a ) by pressing or hammering. 14. Filling machine of rotating design for low-oxygen filling of a beverage, in particular beer, into bottles ( 8 ), with several filling elements ( 1 ) provided on a rotor ( 2 ) which can be driven to rotate about a vertical machine axis, characterized in that the filling elements ( 1 ) are designed for optionally filling the filling material into bottles made of glass or into bottles made of plastic, for example PET bottles, in accordance with one of the preceding claims.