METHOD AND FILLING SYSTEM FOR FILLING CONTAINERS

Abstract

Using a filling point to fill a container with liquid filling-material fed by a supply line through which filling material at a supply-line pressure is made available for filling the containers includes using a control circuit to regulate flow velocity at which filling material flows into the container by opening a liquid valve, opening a regulating valve upstream of the liquid valve, sensing flow velocity of the filling material, comparing the flow velocity with a target flow velocity, and using the regulating valve to regulate the flow velocity such that the flow velocity is independent of a pressure difference between the supply-line pressure and a filling pressure set in the container.

Claims

1-22. (canceled)

21. A method comprising using a filling point to fill a container with liquid filling-material fed by a supply line through which filling material at a supply-line pressure is made available for filling said containers, said method comprising using a control circuit to regulate flow velocity at which filling material flows into said container, wherein using said control circuit comprises opening a liquid valve, opening a regulating valve upstream of said liquid valve, sensing flow velocity of said filling material, comparing said flow velocity with a target flow velocity, and using said regulating valve to regulate said flow velocity such that said flow velocity is independent of a pressure difference between said supply-line pressure and a filling pressure set in said container, wherein opening said regulating valve occurs concurrently with opening said liquid valve or after opening said liquid valve.

22. The method of claim 21, further comprising using said control circuit to reduce said supply-line pressure to a filling pressure in said container, said filling pressure in said container being independent of said supply-line pressure and freely selectable.

23. The method of claim 21, wherein using said regulating valve to regulate said flow velocity comprises maintaining said flow velocity at a constant value.

24. The method of claim 21, wherein using said regulating valve to regulate said flow velocity comprises causing said flow velocity into said container to vary according to a predetermined velocity profile.

25. The method of claim 21, further comprising selecting said target flow velocity as a function of said filling material.

26. The method of claim 21, further comprising selecting said target flow velocity as a function of said container.

27. The method of claim 21, further comprising selecting said target flow velocity as a function of a filling method to be used by said filling point to fill said container.

28. The method of claim 21, further comprising selecting said control circuit to comprise a governor and a magnetic-inductive flow meter through which said filling material passes.

29. The method of claim 21, wherein said filling point is one of a plurality of identical filling points, wherein flow velocity of each filling point is regulated by a discrete control circuit associated with said filling point.

30. The method of claim 21, wherein said filling point is one of a plurality of filling points, wherein said supply line is common to all of said filling points, and wherein said method further comprises using said supply line to feed filling material to all of said filling points.

31. The method of claim 21, further comprising shutting off said liquid valve to end delivery of said filling material.

32. The method of claim 21, further comprising preloading said container to a preloading pressure, opening said liquid valve after having preloaded said container, and applying said preloading pressure to a portion of said product line.

33. The method of claim 21, further comprising reducing pressure of said filling material along a throttle section that is downstream of said regulating valve.

34. The method of claim 21, wherein using a filling point to fill a container comprises using said filling point to carry out open-jet filling.

35. The method of claim 21, wherein using a filling point to fill a container comprises using said filling point to carry out pressure filling.

36. The method of claim 21, further comprising opening said regulating valve between twenty and eighty milliseconds after having opened said liquid valve.

37. An apparatus for filling a container with liquid filling material, said apparatus comprising a filling point having a delivery opening, a product channel, a supply line, a valve, a control circuit, and a sensor, wherein said product channel connects said supply line to said delivery opening, wherein said supply line carries said filling material, and wherein said control circuit controls said valve to regulate flow velocity of filling material flowing into said container in response to a signal provided by said sensor so as to conform to a desired flow velocity.

38. The apparatus of claim 37, wherein filling material in said supply line is at a supply pressure, wherein said container is at a filling pressure, wherein there exists a different between said supply pressure and said filling pressure, wherein said control circuit is configured to control said flow velocity independently of said difference, to permit said filling pressure to be freely selectable, and to reduce said supply pressure.

39. The apparatus of claim 37, further comprising a governor, wherein said first valve is a regulating valve arranged in said product channel such that filling material flows through said regulating valve, wherein said sensor comprises flow meter arranged in said product channel to measure flow rate and to provide a signal to said governor, and wherein said governor controls said regulating valve to conform to a target flow rate based at least in part on said signal.

40. The apparatus of claim 37, wherein said first valve, which is arranged in said product channel, is configured to close said product channel upon completion of delivery of said filling material into said container and also to be regulated by a governor that receives a signal from said sensor, said signal being indicative of flow rate through said product channel, wherein, as a result of being regulated by said governor, flow through said product channel conforms to a target flow rate.

41. The apparatus of claim 37, further comprising a second valve and a governor, wherein said first valve is a regulating valve that is arranged in said product channel upstream of said liquid valve, wherein said second valve is a shut-off valve that closes said product channel to prevent further delivery of filling material upon completion of container filling, wherein said governor controls said first valve based on a signal received from said sensor, and wherein, as a result of being regulated by said governor, flow through said product channel conforms to a target flow rate.

42. The apparatus of claim 37, wherein said filling point is one of a plurality of filling points, wherein said control circuit is common to at least one other filling point from said plurality of filling points.

43. The apparatus of claim 37, wherein said filling point is one of a plurality of filling points, wherein said control circuit is independent of other filling points in said plurality of filling points.

44. The apparatus of claim 17 wherein said filling point is a first filling point of a group of filling points that comprises a second filling point, wherein said product channel comprises a common section that is common to said first and second filling points, a first branch section that is leads from said common section to said first filling point, and a second branch section that leads from said common section to said second filling point, wherein said first valve is provided in said common section, wherein said sensor of said first filling point comprises a first flow meter, wherein said second

45. The apparatus of claim 37, further comprising a second valve and a probe that senses filling-material level in said container, wherein said second valve is a shut-off valve that enables and disables delivery of said filling material, wherein said probe provides a signal for use in controlling said second valve.

46. The apparatus of claim 37, further comprising a second valve and a flow meter that senses filling-material level in said container, wherein said second valve is a shut-off valve that enables and disables delivery of said filling material, wherein said flow meter provides a signal that controls said second valve.

47. The apparatus of claim 37, further comprising a second valve and a weighing device that senses filling-material level in said container, wherein said second valve is a shut-off valve that enables and disables delivery of said filling material, wherein said weighing device provides a signal that controls said second valve.

48. The apparatus of claim 37, further comprising a rotor and a pressure regulator, wherein said filling point is one of a plurality of filling points disposed on a periphery of said rotor, wherein said supply line is common to all of said filling points, wherein product channels of each of said filling points connect to said supply line, wherein said supply line is connected via said pressure regulator to a source that supplies said filling material under pressure, wherein said source is outside said rotor.

49. The apparatus of claim 37, further comprising a throttle section in which pressure is reduced according to a predetermined profile, wherein said throttle section is provided in said product channel downstream of said valve and upstream of said delivery opening.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The invention is described in greater detail below by reference to FIGS. 1-3, which show different embodiments of filling systems for filling containers with a liquid filling-material.

DETAILED DESCRIPTION

[0027] FIG. 1 shows a first filling-system 1 for pressure-filling containers 2 with filling material. The first filling-system 1 has first and second filling-blocks 3, each of which has a filling point 4. Each filling block 3 carries out controlled filling of a container 2 that is sealed against the filling point 4 through an open filling tube 5. The illustrated first filling-system 1 is one of many identical filling systems that are disposed around the circumference of a rotor that rotates about a vertical machine-axis MA.

[0028] Each filling point 4 has a product channel 6 that extends between a supply line 7 and the filling point's delivery opening. The supply line 7 is common to and supplies filling material to all the filling blocks 3. In the illustrated embodiment, the supply line 7 extends between the delivery opening and the filling tube 5.

[0029] A regulating valve 8 and a flow meter 9, both of which lie along the product channel 6, cooperate to regulate the volumetric flow of filling material through the product channel 6 either continuously or incrementally. In doing so, the flow meter 9 detects the quantity of filling material flowing through the channel 6 per unit time and supplies a corresponding electrical signal to an electronic controller or governor 18. In response, the governor 18 regulates the flow through the regulating valve 8.

[0030] A liquid valve 10 downstream of the flow meter 9 functions as an on/off valve that permits delivery of filling material when open and blocks its delivery when closed.

[0031] The regulating valve 8 thus functions as a controlled or regulated throttle that is part of a control circuit. For a given volumetric flow-rate of the filling material, a pressure difference is present at the regulating valve 8 between the pressure in the container 2 and the pressure upstream, for example in the supply line 7 or any other element of the filling system that feeds or supplies the filling material.

[0032] The first filling-system 1 includes first, second, and third controlled gas-paths 11, 12, 13 that, when the container 2 is located in sealed position against the filling point 4, are also connected to the container's interior and are also associated with each filling device 3 or each filling point 4.

[0033] A first control-valve 11.1 connects the first gas-path 11 to a first annular-channel 14. A second control-valve 12.1 connects the second gas-path 12 to a second annular-channel 15. In addition, the second gas-path 12 includes a throttle valve 17 along it. A third control-valve 13.1 connects the third gas-path 13 to a third annular-channel 16. The first, second, and third annular-channels 14, 15, 16 are provided for all the filling devices 3 and the filling points 4 in common.

[0034] A pressure regulator 7.1 connects the supply line 7 to a source of filling material. The source supplies the filling material under pressure so that a constant or essentially constant filling pressure is present in the supply line 7 during the filling operation.

[0035] During the filling operation, a vacuum pump 14.1 maintains the first annular-channel 14 at a vacuum or negative pressure. The second annular-channel 15 vents to the environment, as a result of which it carries ambient or atmospheric pressure. The third annular-channel 16 carries a preloading gas maintained at a pressure by a pressure regulator 16.1 that connects to a gas source. The preloading gas is typically an inert gas such as carbon dioxide at a preloading pressure that is slightly below the filling pressure.

[0036] The filling-material source, the gas source, and the vacuum pump are outside the rotor and do not rotate with it. The corresponding connections to the first, second, and third annular-channels 14, 15, 16 therefore extend through a rotary joint 21 between the rotor and a machine frame.

[0037] At each filling point 4, the first filling-system 1 makes possible a filling process that comprises the typical process steps described below. During the process, the container 2 that is being filled is sealed against the filling point 4. Unless otherwise indicated as open, all valves are closed.

[0038] A process controller controls the opening and closing of the first, second, and third control-valves 11.1, 12.1, 13.1 during a filling process.

[0039] The filling process begins with opening the first control-valve 11.1 to connect the container's interior to the first annular-channel 15 via the first gas-path. Since the first annular-channel 14 carries a vacuum, this evacuates the container 2.

[0040] The next step is to open the third control-valve 13.1 to connect the container's interior with the third annular-channel 16. This preloads the container's interior with the preloading gas and applies the preloading pressure to the container's interior. The steps of evacuating and purging the container can be carried out multiple times.

[0041] With the third control-valve 13.1 remaining open, the next step is to open the liquid valve 10 and, at the same time or shortly thereafter, to open the regulating valve 8. As a result of opening the liquid valve 10, the preloading pressure in the container 2 becomes present in the product line 6. This begins the filling process. During filling, the governor 18 regulates the flow through the regulating valve 8 so that it matches a pre-stored profile that is specific to the liquid filling material, the container, and the filling method. The profile is stored, for example, in the governor 18 or in a process control computer of the first filling-system 1 that interacts with the governor 18. As filling material enters the container, it displaces preloading gas from the container's interior through the still-open third control-valve 13.1. The displaced preloading gas thus returns to the third annular-channel 16.

[0042] When the flow meter 9 indicates that the required amount of filling material has entered the container 2, it sends a signal to the governor 18 to halt filling.

[0043] In a subsequent calming and relieving step, the liquid valve 10 and/or the third control-valve 13.1 remain closed so as to calm the filling material that has flowed to the container 2. After the end of a given calming period, the second control-valve 12.1 opens. This relieves pressure in the container 2 so that it matches that in the second annular-channel 15.

[0044] FIG. 2 shows a second filling-system la that differs from the first filling-system 1 by having two filling points 4 combined to form a dual filling element 3a. The first, second, and third control-valves 11.1, 12.1, 13.1 are therefore provided for both filling points 4 in common. In this configuration, the product channel 6 includes a main section 6.1 that connects the supply line 7 and two branch sections 6.2, each of which leads to a corresponding filling point 4 or local liquid valve 10. Each branch section 6.2 comprises a flow meter 9 and a liquid valve 10.

[0045] A common regulating valve 8 lies along the main section 6.1 between the branch sections 6.2 and the supply line 7. The regulating valve 8 is again part of a control circuit which comprises two flow meters 9, one for each branch section 6.2, as well as a governor 18, which controls the regulating valve 8 as a function of the target value of the filling speed and an averaged measured value calculated from the output signals of the two flow meters 9. The governor 18 controls the regulating valve 8 in the same way to achieve a target filling profile.

[0046] The process steps for using the second filling-system 1a are the same as those discussed in connection with the first filling-system 1. These process steps are carried out simultaneously for both the filling points 4.

[0047] Like the first filling-system 1, the second filling-system 1a is also configured for volumetric filling of containers 2, i.e. the liquid valves 10 are each closed as a function of the signal from the flow meter 9 that is associated with the respective filling point 4.

[0048] FIG. 3 shows as a third filling-system 1b in which once again two filling points 4 are combined to form a dual filling element. The third filling-system 1b differs from the second filling-system 1a by having a probe 19 that determines when it is time to end the filling. The probe 19 is a filling-height probe that sends an electrical signal when the level of filling material in the container 2 reaches a target value.

[0049] In the third filling-system 1b, the liquid valves 10 of the two filling points 4 are both provided in the branch sections 6.2 of the product channel 6, while a common flow meter 9 for both filling points 4 and a common regulating valve 8 for both filling points 4 are provided in main section 6.1. Together with the flow meter 9 and the governor 18, the regulating valve 8 again forms part of a control circuit that regulates the rate at which filing material flows into containers 2. It does so by comparing a measured value supplied by the flow meter 9 with a target value of the filling speed and controlling the regulating valve 8 to so that the actual flow rate tracks a pre-determined filling speed characteristic or profile.

[0050] The third filling-system 1b uses the same process steps described for the first filling-system 1 by appropriate operation of the first, second, and third control-valves 11.1, 12.1, 13.1, which are again common to both filling points 4 of this dual filling element. Except for the final closing of the liquid valves 10, which is effected for both filling points 4 individually as a function of the signal from the filling height probe 19, the other process steps again take place simultaneously.

[0051] Thus the essential core of the above described filling systems 1,1a and 1b and/or of the methods performed with these systems lies in the fact that, during the filling process, a control circuit monitors and regulates the filling speed so that at any time during the filling phase the desired filling speed is exactly maintained even though the filling material is fed under pressure to the individual filling points 4 not from a partly-filled filling-material tank but from a supply line 7 or from a tank or annular channel that is completely filled with the filling material, and that the pressure in the supply line 7 is reduced to an independent and/or freely selectable filling pressure in the container 2.

[0052] Filling systems have so far been described for filling the containers 2 that during the filling process, and in particular during the filling phase as well, are sealed against the filling point 4. However the active regulation of filling speed is also suitable for pressureless filling of containers and for open jet filling in particular. The filling points 4 of such a filling system comprise the same configuration as has been described for the first, second, and third filling-systems 1, 1a, 1b. However, the first, second, and third controlled gas-paths 11, 12, 13 and their associated first, second, and third control-valves 11.1, 12.1, 13.1 are omitted, as these are not needed for open-jet filling.

[0053] It has also been assumed above that, with the first and second filling-systems 1, 1a which are configured for volumetric filling, the flow meters 9 that are part of the control circuit for regulating the filling speed also supply the signal for the final closing of the filling point 4 or liquid valve 10.

[0054] In an alternative embodiment, an additional sensor system detects the quantity of filling material flowing to the container 2 for deciding when to terminate the filling phase. Examples of an additional sensor system include an additional flow meter or other measurement system, such as a weighing system.

[0055] Some embodiments feature a throttle section 20, as shown in FIG. 1, disposed in the product channel 6 upstream of the liquid valve 10. Such a throttle section 20 causes a defined and controlled reduction in filling-material pressure. In particular, the throttle section 20 is configured such that the pressure of the filling material along the throttle section 20 decreases slowly and evenly to avoid turbulent flow. Such turbulent flow is particularly undesirable for carbonated beverages because low-pressure zones in the flow can cause carbon dioxide to come out of solution

[0056] When used in conjunction with open jet filling this can significantly reduce any ingress of micro-bubbles into the container to be filled when bottling carbonated drinks. The dosing of such bubbles and micro-bubble ingress into the already bottled filling material also makes it possible to significantly reduce the filling pressure towards atmospheric pressure.

[0057] Another advantage is also offered by the fact that it is possible to further reduce the weight of containers or bottles made from PET and so significantly reduce the cost of a filling plant or filling line and of any necessary cooling of the container base. Glass breakage is reduced when containers made from plastic are being filled. The consumption of preloading gas can also be reduced.

[0058] Pressure sensors with which the pressure is monitored and/or set and/or regulated to a target value are also preferably provided in the product channels 6 and/or in the product supply channel 7 and/or in the annular channels 14 and 16 and/or in the gas paths connected to these annular channels.