Filling element, filling system, and method for filling containers

Abstract

A filling element has a gas valve that controls flow of gas through a gas channel that extends into or faces the container during filling thereof. The gas valve transitions between discrete states, which includes a fully-open state, a closed state, and one or more partially-open states.

Claims

1. An apparatus for filling containers with a filling material, said apparatus comprising a filling element, said filling element comprising a fluid channel through which liquid filling-material provided by a filling-material tank flows, a liquid valve in said fluid channel, a discharge opening downstream of said liquid valve for discharging said filling material into a container with said liquid valve opened, a gas channel having a gas opening through which gas flows into said container, and a gas valve that controls flow of gas through said gas channel, wherein said gas opening either extends into or faces said container during filling thereof and wherein said gas valve is configured to transition between a plurality of discrete states, said states comprising a fully-open state, a closed state, and at least one partially-open state, said fully-open state and said partially-open state having different flow resistances, wherein said gas valve includes a gas-valve tube with a seal seat and a gas-valve needle that moves relative to said gas-valve tube, said gas-valve needle comprising a sealing surface and a choke separated by a shaft, wherein, as said gas-valve needle moves distally towards said container along a closing direction, said seal seat eventually engages said sealing surface and closes said gas valve wherein proximal movement of said valve needle in a direction opposite said closing direction, causes said gas valve to assume a partially-open position in which said choke is within a constriction of said gas-valve tube, thereby causing only a narrow annular gap to remain between said choke and a wall of said gas-valve tube at said constriction, wherein further proximal movement of said choke raises said choke out of said constriction and completely opens said gas valve.

2. The apparatus of claim 1, wherein said states comprise first and second partially-open states that have different flow resistances.

3. The apparatus of claim 1, wherein said gas valve comprises a gas-valve tube and a gas-valve needle that moves relative to said gas-valve tube along a closing direction to transition from said fully-open state to said closed state, wherein said gas-valve tube comprise a seal seat and said gas-valve needle comprises a sealing surface, wherein, in said closed state, said sealing surface lies on said seal seat to close said gas valve, and wherein, in said fully-open state, said sealing surface is at a distance from said seal seat, thereby permitting flow through said gas valve.

4. The apparatus of claim 1, wherein said gas valve comprises a gas-valve tube comprising a seal seat and a constriction distal to said seal seat, said constriction having a constriction diameter and a gas-valve needle that moves distally relative to said gas-valve tube along a closing direction when transitioning to said closed state, wherein said gas-valve needle comprises a sealing surface and a choke distal to said sealing surface, said choke having a choke diameter that is smaller than said constriction diameter, thereby permitting said choke to pass through said constriction during distal movement of said gas-valve needle.

5. The apparatus of claim 1, wherein said gas valve comprises a gas-valve tube and a gas-valve needle that moves distally relative to said gas-valve tube along a closing direction when transitioning to said closed state, wherein said gas-valve tube comprises a seal seat, a constriction distal to said seal seat, and a slot distal to said constriction, said slot being one of annular and lateral, and wherein said gas-valve needle comprises a sealing surface, a choke distal to said sealing surface, and a shaft that extends between said choke and said sealing surface, said choke having a choke diameter that is less than a diameter of said constriction, thereby permitting said choke to pass through said constriction during distal movement of said gas-valve tube.

6. A method for using a filling element that comprises comprising a fluid channel through which liquid filling-material provided by a filling-material tank flows, a liquid valve in said fluid channel, a discharge opening downstream of said liquid valve for discharging said filling material into a container with said liquid valve opened, a gas channel having a gas opening through which gas flows into said container, and a gas valve that controls flow of gas through said gas channel, wherein said gas opening either extends into or faces said container during filling thereof and wherein said gas valve is configured to transition between a plurality of discrete states, said states comprising a fully-open state, a closed state, and at least one partially-open state, said method comprising causing said gas valve to be in said partially-open state to dry filling-material residues in said gas channel of said filling element, said method further comprising filling said container with liquid filing-material drawn from said filling-material tank, whereby gas flows through said gas channel at a speed that is slower than a speed that results when said gas valve is in said fully-open state, said fully-open state and said partially-open state having different flow resistances.

7. A method for using a filling element that comprises comprising a fluid channel through which liquid filling-material provided by a filling-material tank flows, a liquid valve in said fluid channel, a discharge opening downstream of said liquid valve for discharging said filling material into a container with said liquid valve opened, a gas channel having a gas opening through which gas flows into said container, and a gas valve that controls flow of gas through said gas channel, wherein said gas opening either extends into or faces said container during filling thereof and wherein said gas valve is configured to transition between a plurality of discrete states, said states comprising a fully-open state, a closed state, and at least one partially-open state, said method comprising pressurizing said container with a pressurizing gas, opening said liquid valve, and opening said gas valve, whereby said filling material drawn from said filling-material tank and flowing via said gas channel through said discharge opening and into said container displaces pressurizing gas that is in said container through said gas channel, wherein, while said container is being filled with said filling material, causing said gas valve to transition into said partially-open state for at least a portion of time during which filling with said filling material takes place, whereby inflow speed of said filling material is lower than it would have been had said gas valve been in said fully-open state.

8. The apparatus of claim 1, wherein said states comprise first, second, and third partially-open states that have different flow resistances.

9. The apparatus of claim 1, wherein said gas valve is configured to transition into said partially-open state after said container has been filled and while said gas opening is still located in said container.

10. The apparatus of claim 1, wherein said gas valve is configured to transition into said partially-open state while no container is sealed at said filling element.

11. The apparatus of claim 1 wherein said gas valve is configured to transition into said partially-open state immediately before flushing said container.

12. The apparatus of claim 1 wherein said gas valve is configured to transition into said partially-open state immediately before pressurizing said container.

13. The apparatus of claim 1, wherein said gas valve is configured to transition into said partially-open state as a first step of flushing said container.

14. The apparatus of claim 1, wherein said gas valve is configured to transition into said partially-open state as a first step of pressurizing said container.

15. The apparatus of claim 1, wherein causing said gas valve is configured to transition into said partially-open state and to transition into said fully open state following lapse of a pre-determined time interval after said transition into said partially-open state.

16. The apparatus of claim 1, wherein said gas valve is configured to transition into said partially-open state to dry residues in said gas channel prior to filling said container from said filling-material tank.

17. The apparatus of claim 1, wherein said gas valve is configured to partially choke flow of flushing gas sufficiently to avoid atomization of residues in said gas channel.

18. The apparatus of claim 1, wherein said gas valve is configured to be in said partially-open state while said filling element fills said container, whereby inflow speed of said filling material is lower than it would have been had said gas valve been in said fully-open state.

19. The apparatus of claim 1, wherein said gas valve is configured to transition into said partially-open state after said container has been filled and while said gas opening is directly above said container.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) These and other features of the invention will be apparent from the following detailed description and the accompanying figures, in which:

(2) FIGS. 1a-1e show longitudinal sections through a filling element;

(3) FIGS. 2a-2e show longitudinal sections through the gas valve of FIGS. 1a-1e at various stages of filling; and

(4) FIG. 3 shows a longitudinal section through a further embodiment of a gas valve for use in the filling element of FIGS. 1a-1e.

(5) Identical reference numbers are used in the Figures for elements of the invention which are the same or have the same effect. Moreover, for the sake of easier overview, only those reference numbers are represented in the individual FIGS. which are necessary for the description of the respective Figure.

DETAILED DESCRIPTION

(6) FIGS. 1a-1e show longitudinal sections through a filling element 1 at different stages of a filling process. The filling element 1 is arranged at a transport element 2 of a filling system 3, of which only a section is shown here.

(7) The filling element 1 is connected, preferably for the duration of the filling process, to the container 4 that is intended to be filled with a fluid filling material 5, which is provided from a tank 6. The fluid filling material 5 encompasses any type of liquid that can be filled into containers 4. However, the illustrated filling element 1 and the filling method are particularly useful for filling containers 4 with beverages, predominantly beverages that have been carbonated with carbon dioxide. Although the container 4 is shown as a bottle, the filling element 1 and the associated filling process are also well-suited, with slight, for other containers, such as cans or beakers.

(8) The liquid channel 7 connects to the tank 6 and ends in a discharge opening 9. The discharge opening 9 faces the container 4. A liquid valve 8 along the liquid channel 7 opens to allow filling material 5 to enter the container 4.

(9) The gas channel 10 conveys gases that have served a variety of functions, such as a flushing gas, a pressurizing gas, and return gas that is displaced from the container 4 during filling thereof. Some embodiments feature plural gas channels 10, each of which carries a different gas.

(10) The gas channel 10 comprises a gas opening 11. In the illustrated embodiment, the gas opening 11 extends into the container's interior 12. In other embodiments, the gas opening 11 does not extend into the container 4 but nevertheless faces it so that gas can enter the container 4.

(11) A gas valve 13 along the gas channel 10 switches between the states of being opened, being closed, and being partially open. In some embodiments, there are multiple partially-open states. A particular embodiment has three partially-open states. These different partially-open states offer different flow resistances, which are optimized for various stages of filling.

(12) The filling process begins with the transport element 2 receiving the container 4 from an inlet star and connecting it to the filling element 1. In some filling processes, the container 4 is sealed tightly against the filling element. However, other filling processes do not require a tight seal.

(13) As shown in FIG. 1a, the filling process continues with the liquid valve 8 and the gas valve 13 both being closed. The container 4 is then exposed to a vacuum 14, thereby removing any residual gas in the container 4.

(14) FIG. 1b shows a flushing step that includes partially opening the gas valve 13. This permits a flushing gas, which is typically carbon dioxide, to dry any filling material residue still present in the gas channel 10. The vacuum 14 is then used to suck any flushing gas flowing into the container 4.

(15) atomized It is also possible to further open the gas valve 13. This causes flushing gas to carry any filling-material residues present in the gas channel 10. Some of these residues may be carried into the container 4 through the gas opening 11. However, because the gas valve 13 partially chokes the flow of flushing gas, these residues move slowly enough to avoid atomization. This is useful to prevent introduction, into the container 4, of certain types of bacteria that thrive in carbon dioxide.

(16) FIG. 1c shows the next step, which is to pressurize the container 4 with a pressurizing gas, such as carbon dioxide. This is carried out by fully opening the gas valve 13. To prevent this pressurizing gas from being sucked out of the container 4, it is useful to also close a vacuum valve 15, thus disconnecting the vacuum source 14. As a result, pressure builds within the container 4.

(17) In this case, it is possible to fully open the gas channel 10 because all filling-material residues will have already been removed during the preceding flushing step. On the other hand, if the pressurizing gas is to be introduced using a channel that differs from that used for flushing, the gas valve 13 should only be partially opened. This avoids the risk of introducing filling-material residues that may carry bacteria of the type that thrive in carbon dioxide.

(18) The next step is to introduce the actual liquid filling-material, as shown in FIG. 1d. The liquid filling-material is introduced against the pressure of the pressurizing gas. In this step, the gas channel 10 plays the role of a return gas channel that can convey return gas as the filling material displaces it from the container. In this step, the liquid valve 8 is opened and the gas valve 13 is, at first, almost completely opened. This permits rapid outflow of the pressurizing gas from the container and thus rapid inflow of liquid filling-material into the container 4.

(19) Due to the slower inflowing filling material 5 it is easier for the desired filling height or filling quantity to be attained in the container 4. The next step is to slow down the filling as the desired filling height is reached. This provides a sensor that senses the filling height with enough time to make an accurate measurement and send an appropriate signal to stop filling. This deceleration step includes closing or choking the gas valve 13, thus reducing the rate at which return gas leaves the container. This slows down the rate at which filling material can enter.

(20) A variety of ways are used to measure the filling height. These include an optical sensor or a hollow probe near the gas opening 11. An alternative method is to use the Trinox process, in which a container continues to be filled until the liquid filling-material 5 reaches the gas opening 11. When this happens, the gas opening 11 becomes submerged. As a result, no more return gas can escape. This halts the filling process. A sensor in the gas channel 10 recognizes the rising filling material 5 and determines that the filling height has been reached.

(21) Upon reaching the desired filling height, the liquid valve 8 closes and the gas valve 13 also closes. A pressure-equalization valve 16 relieves pressure in the container 4.

(22) When filling is complete, the container 4 is separated from the filling element and transferred to an outlet star for transport to a subsequent container-treatment machine.

(23) FIGS. 2a-2e show the gas valve 13 in stages corresponding to those in FIGS. 1a-1e.

(24) In FIG. 2a, the gas valve 13 is shown in its closed position. The gas valve 13 includes a gas-valve tube 17 with a seal seat 19. A gas-valve needle 18, which moves relative to the gas-valve tube 17, has a sealing surface 20 and a choke 21 separated by a shaft 24. As the gas-valve needle 18 moves distally towards the container 4 along a closing direction S, the seal seat 19 eventually engages the sealing surface 20 and closes the gas valve 13.

(25) Moving the valve needle 18 proximally, in the direction opposite the closing direction S, causes the gas valve 13 to assume a partially-open position, as shown in FIG. 2b. This causes the choke 21 to be within a constriction 22 of the gas-valve tube 17, which is proximal to the seal seat 19. As a result, only a narrow annular gap remains between the choke 21 and the wall of the gas-valve tube 18 at the constriction 22.

(26) Moving the choke 21 further proximally, against the closing direction S, raises it out of the constriction 22 and completely opens the gas valve 13, as shown in FIG. 2c.

(27) Moving the valve needle 18 distally by a small amount in the closing direction S, as shown in FIG. 2d, leaves the gas valve 13 almost completely open, However, with the choke 21 now being closer to the seal seat 19, flow resistance will have changed. A flow resistance that is between that arising at FIGS. 2b and 2d can be achieved by moving the valve needle 18 further in the closing direction S as shown in FIG. 2e. In this position, the choke 21 has moved past the seal seat 19 and the constriction 22 to a region at which the gas-valve tube 17 widens to form a slot 23.

(28) In the position shown, the slot 23 is an annular region that surrounds the choke 21. The shaft 24, meanwhile, lies in the construction 22. Since the shaft's diameter is smaller than that of the choke 21, the flow resistance that arises from having the shaft 24 at the constriction 22 is somewhat less than it would have been had the choke 21 been at the constriction 22 instead. This results in a medium flow resistance.

(29) FIG. 3 shown an alternative gas valve 13 that lacks the slot 23. As a result, the gas valve 13 has more difficult attaining a medium flow resistance as shown in FIG. 2e. However, the gas valve 13 shown in FIG. 3 is simpler and more economical to produce, while still retaining a partially-open state.

(30) 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.