Filling system

Abstract

A filling element includes a common actuator that controls both a liquid valve and a gas valve. The actuator implements a two-stage control stroke. In a first operating state, both the liquid valve and the gas valve are closed. As a result of a first partial stroke in the second operating state, the gas valve opens but the liquid valve remains closed. Then, in a third operating state, as a result of a second partial stroke, the liquid valve is opens while the gas valve remains open.

Claims

1. An apparatus for filling at least one of bottles and containers with a liquid filling-product, said apparatus comprising a single-chamber filling system comprising a filling-product vessel and a filling element arranged below said filling-product vessel, wherein, in operation, said filling-product vessel is partially filled with liquid product that defines a liquid space and a gas space above said liquid space, wherein said filling element extends along a filling-element axis, wherein said filling element comprises a housing, a liquid channel, a discharge opening, a liquid valve, a gas valve, a liquid valve-body, a liquid-valve tappet, a gas-valve body, a gas channel, and an actuator, wherein said liquid channel extends through said housing between a connection to said liquid space and said discharge opening, which is disposed at an end of said liquid channel at an underside of said housing, said underside facing away from said filling-product vessel such that, during filling, liquid product flows into a container through said discharge opening, wherein said liquid valve is arranged in said liquid channel such that said liquid-valve body is arranged coaxially with said filling-element axis so as to be movable axially along said filling-element axis for opening and closing said liquid valve, wherein said liquid-valve tappet is provided on said liquid-valve body, wherein said liquid valve is configured to permit controlled discharge of said filling product into a container arranged in a sealed position against said filling element during a filling operation, wherein said gas channel extends through said liquid-valve tappet between an upper end that opens into said gas space and a lower end that, in operation, extends into a head space of said container, wherein said gas valve is provided in said gas channel such that movement of said gas-valve body opens and closes said gas valve, wherein said actuator comprises a pneumatic actuator that is configured to cooperate with said liquid-valve tappet and with said gas-valve body to cause a controlled motion that comprises at least a first partial stroke and a second partial stroke, wherein said actuator is configured such that said first partial stroke causes said actuator to transition from a first operating state to a second operating state, and said second partial stroke causes said actuator to transition from said second operating state to a third operating state, wherein, when said actuator is in said first operating state, said liquid valve is closed and said gas valve is closed, wherein, when said actuator is in said second operating state, said liquid valve is closed and said gas valve is opened, and wherein, when said actuator is in said third operating state, said liquid valve is opened and said gas valve is opened, wherein said actuator comprises an adapter, an actuator-tappet, a first lift-element, and a second lift-element, wherein said first and second lift-elements are coaxial with said filling-element axis, wherein said adapter is coupled to said liquid-valve tappet, said actuator tappet, and said gas-valve body, wherein said actuator-tappet moves said first lift-element, wherein said second lift-element is disposed to form a stop for stroke movement of said first lift-element such that when said second lift-element is in a first state, said stroke movement of said first lift-element is limited to said first partial stroke, and when said second lift-element is in a second state, said stroke of said first lift-element is equal to a sum of extents of said first and second partial strokes.

2. The apparatus of claim 1, wherein said gas-valve body is movable through said a gas channel that is formed through a liquid-valve tappet that extends along said filling-element axis for opening and closing said gas valve, wherein said gas-valve body cooperates with a valve face formed in said gas channel, wherein said gas-valve body extends through an aperture in said valve face when said gas valve is open, and wherein said gas-valve body extends through said aperture when said gas valve is closed.

3. The apparatus of claim 2, further wherein said gas channel comprises a partial length that passes through said liquid-valve tappet and that receives said gas-valve body, wherein said gas-valve body comprises an upper end that protrudes from out of said liquid-valve tappet, and wherein said upper end of said gas-valve body selectively contacts said actuator.

4. The apparatus of claim 1, wherein said first lift-element comprises a first piston-cylinder arrangement, and wherein said second lift-element comprises a second piston-cylinder arrangement.

5. The apparatus of claim 1, wherein said adapter comprises a first control-face and a second control-face, wherein said liquid-valve tappet comprises a control portion, wherein said gas-valve body lies against said first control-face during said first partial-stroke, wherein said second control-face is axially offset from said control portion when said actuator is in said first operating state, wherein, during axial motion of said liquid-valve tappet, said second control-face engages said control portion only during said second partial-stroke.

6. The apparatus of claim 5, further comprising a spring that is configured to act on said adapter to urge said adapter upward, wherein said adaptor comprises a third control face that, when said actuator is in said first operating state, lies against said control portion of said liquid-valve tappet.

7. The apparatus of claim 6, wherein an axial distance between said second control-face and said third control-face is at least equal to an extent of said first partial stroke plus a thickness of said control portion arranged between said second control-face and said third control-face.

8. The apparatus of claim 1, further comprising a spring configured to pre-load said liquid valve.

9. The apparatus of claim 8, wherein said spring is configured to pre-load said liquid valve towards a closed state, wherein said spring is disposed above said gas-valve body.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

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

(2) FIGS. 1-3 show a vertical cross section of a filling element;

(3) FIG. 4 shows a cross section of an actuator from the filling element shown in FIGS. 1-3;

(4) FIG. 5 shows a cross section of an adapter or control adapter from the filling element shown in FIGS. 1-3; and

(5) FIG. 6 is a close-up view of a cross-section of the filling element of FIGS. 1-3 in the region of its liquid valve and its discharge opening.

DETAILED DESCRIPTION

(6) FIG. 1 shows a ring vessel 1 of a rotary filling machine for filling containers 2 with liquid filling-product. The vessel 1 is part of a rotor that can be driven to rotate about a vertical machine axis MA. The machine axis MA defines a polar coordinate system (r, ) with the periphery of the rotor being located at r=R.

(7) During the filling operation, filling product partially fills the vessel 1 up to a controlled level. The filling product thus divides the vessel's interior into a liquid space 1.1 filled with filling product and a gas space 1.2 that is filled with an inert gas, such as carbon dioxide, nitrogen, or sterile air.

(8) A plurality of filling positions 3 is formed on the underside of the vessel 1. An n.sup.th filling position 3 is located at (R, n.sub.o), where n is an integer and .sub.o is a fixed angular spacing between any two filling positions 3.

(9) Each filing position 3 has a filling element 4 and a container carrier, which is not shown and on which a container 2 stands on its bases. The container carrier holds the container 2 so that it can be sealed against the filling element 4 with its opening pressed over a ring seal 5 of a centering sleeve 6 during the filling operation.

(10) Each filling element 4 has a flat, plate-like filling-element housing 7 having a liquid channel 8 formed therein. A first opening 9 on a floor of the vessel 1 connects the liquid channel 8 to the liquid space 1.1. A second opening 10 on an underside of the housing 7 forms a dispensing opening for the liquid channel 8. It is through this second opening 10 that liquid filling-product flows into a container 2. The ring seal 5 surrounds this second opening 10.

(11) A liquid valve 11 inside the liquid channel 8 controls the discharge of liquid filling-product into the container 2. The liquid valve 11 includes a liquid-valve body 12 formed on a tubular valve-tappet 13 that is coaxial with a vertical filling-element axis FA. When the liquid valve 11 closes, the liquid-valve body 12 lies against a liquid-valve seat formed in the liquid channel 8. Moving the liquid-valve body 12 up and down along the filling-element axis FA opens and closes the liquid valve 11.

(12) The valve tappet 13 also defines a gas channel 14 that continues into a gas pipe 15 extending into a headspace of a container 2 sealed against the filling element 4. The lower end of this gas pipe 15 forms the gas channel's lower opening within the container 2. The gas channel's upper opening opens into the gas space 1.2.

(13) A gas valve 16 at an upper portion of the gas channel 14 controls flow of gas through the gas channel 14. The gas valve 16 includes a needle-like gas-valve body 17 that is coaxial with the filling-element axis FA. When the gas-valve 16 closes, a valve face of the gas-valve body 17 lies against a gas-valve seat formed in the gas channel 14 and hence blocks the gas valve 16. The needle-like gas-valve body 17 has a cross-section that is selected such that the gas channel 14 surrounds the gas-valve body 17 up to the upper open end of the valve tappet 13. Raising the gas-valve body 17 relative to the valve tappet 13 opens the gas valve 16. Lowering it relative to the valve tappet 13 closes the gas valve 1.

(14) A pneumatic actuator 18 on top of and outside the vessel 1 controls both the liquid valve 11 and the gas valve 16. The pneumatic actuator 18 acts via an actuator tappet 19 that is coaxial with the filling-element axis FA.

(15) Referring to FIG. 5, an adapter 20 couples the actuator tappet 19 with a first control portion 17.1 at an upper end of the gas-valve body 17 and with a second control portion 13.1 at an upper end of the valve tappet 13. Electro-pneumatic control valves permit the actuator 18 to cause the actuator tappet 19, and hence the adapter 20 along the filling-element axis FA. To enable this, the adapter 20 features a lower piston-cylinder arrangement 18.1 and an upper piston-cylinder arrangement 18.2, each of which forms a pneumatic lift element.

(16) Referring to FIG. 4, the lower piston-cylinder arrangement 18.1 forms a lower control chamber 21.1 and includes a lower piston 21. The actuator tappet 19 is effectively a lower-piston rod of this lower piston 21. An opening spring 24 surrounds the actuator tappet 19.

(17) Meanwhile, the upper piston cylinder arrangement 18.2 forms a supra-piston control chamber 22.1 above an upper piston 22 and a sub-piston control chamber 22.2 lying below the upper piston 22. The upper piston 22 has an upper-piston rod 23 that is coaxial with the filling-element axis FA.

(18) A chamber of the lower piston-cylinder arrangement 18.1 outside the filling product vessel 1 receives the opening spring 24. The adapter 20 enables the opening spring 24 to open the liquid valve 11 and the gas valve 16. A bellows seal 25 seals the passage region of the actuator tappet 19 through the top of the filling product vessel 1.

(19) In FIG. 1, the actuator 18 has placed the filling element 4 in a first operating state. In this first operating state, both the liquid valve 11 and the gas valve 16 are closed, and a control pressure pressurizes the lower control chamber 21.1. This control pressure generates a closing force that overcomes the spring force of the opening spring 24.

(20) In FIG. 2, the actuator 18 has placed the filling element 4 in a second operating state. In this second operating state, a container 2 is sealed against the filling element 4, the gas valve 16 is open and the liquid valve 11 is closed.

(21) To reach the second operating state shown in FIG. 2, the lower control-chamber 21.1 is depressurized so that the opening spring 24 can lift the adapter 20. A resulting first partial stroke H1 moves the gas-valve body 17 upward, thus opening the gas valve 16. This permits the container interior to be preloaded with pressurized gas through the gas channel 14. With the gas valve 16 open, it is also possible to provide a pressure balance between the container's interior and the gas space 1.1.

(22) Meanwhile, compressed air pressurizes the supra-piston control chamber 22.1 above the upper piston 22. Thus, when the upper end of the actuator tappet 19 comes to rest against the upper-piston rod 23 of the upper piston-cylinder arrangement 18.2, the pressurized supra-piston control chamber 22.1 limits the first partial stroke H1.

(23) In FIG. 3, the actuator 18 has placed the filling element 4 in a third operating state in which the liquid valve 11 is now open. In this third operating state, the supra-piston control chamber 22.1 and the lower control chamber 21.1 have been depressurized. This permits the opening spring 24 to further lift the liquid-valve tappet 13 in a second partial stroke H2 of the actuator 18. This, in turn, opens the liquid valve 11.

(24) Referring to FIG. 5, the adapter 20 is configured such that, by the completion of the first partial stroke H1, a first control face 20.1 thereof has engaged the first control portion 17.1 of the gas-valve body 17, but a second control face 20.2 of the adapter 20 does not engaged the second control portion 13.1 of the liquid-valve tappet 13 until after the second partial stroke H2 has begun. As a result, the liquid-valve tappet 13 cannot begin to move until after the second partial stroke H2 has begun.

(25) In the embodiment shown, this delayed opening of the liquid valve 11 is achieved by having the second control portion 13.1 be a plate or flange and having the adapter 20 undercut the liquid-valve tappet 13 at its upper end below the second control portion 13.1. Furthermore the arrangement is such that, during the first partial stroke H1, the adapter 20 moves up along the liquid-valve tappet 13 without coming to rest against the second control portion 13.1 and thus lifting the liquid-valve tappet 13.

(26) During the filling procedure, liquid filling-product flowing into the container displaces gas already present therein. The now open gas channel 14 conducts this displaced gas into the gas space 1.2.

(27) As the level of filling product rises, eventually it submerges the gas pipe 15 that extends into the headspace of the container 2. When this happens, the gas in the container can no longer be enter the gas pipe 15. As a result, filling stops. In this way, the lower open end of the gas channel 14 determines the fill level.

(28) Once filling is complete, the actuator 18 closes both the liquid valve 11 and the gas valve 13 by the lowering the adapter 20 and pressurizing the lower control chamber 21.1 with the control pressure. Meanwhile, gravity moves the gas-valve body 17 downward along the filling-element axis FA, thus closing the gas valve 16. The liquid valve 11 closes when the adapter 20 comes to rest with a third control face 20.3 against the top of the second control portion 13.1 and the control pressure in the lower control chamber 21.1 presses the liquid-valve body 12 against its liquid-valve seat.

(29) The invention has been described above with reference to an exemplary embodiment. Numerous changes and derivations are possible without leaving the inventive concept on which the invention is based. Thus instead of the first and second piston-cylinder arrangements 18.1, 18.2, other pneumatic lifting elements may be used.