METHOD AND DEVICE FOR FILLING AN OPEN CONTAINER

Description

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to German Patent Application No. 102024119776.5, filed Jul. 11, 2024, the entirety of which is incorporated herein by reference.

AREA OF APPLICATION AND PRIOR ART

The invention relates to a method and a device for filling a container open at the top with a flowable or powdery product using a negative pressure generated inside the container. The invention relates in particular to a method and a device for filling a container open at the top with coffee powder or milk powder using a negative pressure generated inside the container.

Filling of a container using a negative pressure generated inside the container is also referred to as vacuum filling in connection with the application.

A device and a method for vacuum filling of containers open at the top are known for example from DE 102022203817 B4. The device known from DE 102022203817 B4 comprises a filling head with a filling channel having a free end and with a gas channel having a container opening and a connection opening, and a gas-tight jacketing receiving the container in the filling position, wherein gas is dischargeable out of the container and gas is suppliable to the container via the gas channel in a filling position, wherein the jacketing adjoins the filling head and/or the container in sealing manner at least in the filling position in order to provide a gas-tightly closed gap between the jacketing and the outer container wall; wherein a gap connection opening is provided; wherein gas is dischargeable out of the gap and gas is suppliable to the gap via the gap connection opening; wherein a control device is provided which is configured to connect fluidically the container and the gap to a negative pressure source for a product discharge such that negative pressure is generatable up to a first pressure level in the container and the gap, and in order to connect fluidically the container and the gap to a gas source after a product discharge such that a gas is suppliable to the container and to the gap; and wherein the control device is further configured to connect fluidically the container and the gap to the negative pressure source after the product discharge and before a gas supply for degassing subsequent to the product discharge such that negative pressure is generatable inside the container and the gap up to a second pressure level below the first pressure level.

Object and Solution

It is the object of the invention to provide a method and a device permitting a reliable filling of a container open at the top with a flowable product, in particular with coffee powder or with milk powder, using a negative pressure generated inside the container.

This object is solved by the subject matter having the features of claims 1, 7, and 13. Advantageous embodiments are described in the dependent claims.

According to a first aspect, a method is provided for filling a container open at the top with a flowable product, in particular with coffee powder or with milk powder, using a filling head, that is gas-tightly placed onto the container, wherein the filling head has a filling channel and a gas channel, wherein the container is received in a gas-tight jacketing which adjoins the filling head and/or the container in sealing manner at least in a filling position in order to provide a gas-tightly closed gap between the jacketing and an outer container wall, wherein the filling channel has a free end which projects into the container with an immersion depth in the filling position; wherein negative pressure is generated inside the container and the gap in the filling phase; wherein the negative pressure in the container effects a product discharge via the filling channel up to a filling level at least substantially corresponding to the immersion depth; wherein after the filling phase gas is supplied to the container and to the gap in a gassing phase; wherein an inert gas is supplied at least to the container in the gassing phase; and wherein a fill weight of the container is determined and compared with a target weight after the filling phase and before the gassing phase, with topping up taking place if the determined fill weight is below the target weight.

The terms “a” or “an” are generally used only as the indefinite article “a/an”, and not as “one” in the numerical sense. The terms “first”, “second” etc. are intended only to differentiate and not to indicate a sequence. In the same way, use of the term “first” does not necessarily require the presence of a second element or component.

A gas-tight channel is referred to as a gas channel herein, wherein a gas discharge out of the container and the gap and a gas supply to the container and the gap are made via a single gas channel, depending on the embodiment. The gas channel has one or more connection openings for that purpose. In other embodiments, two gas channels or more than two gas channels are provided for a gas discharge out of the container and the gap and for a gas supply to the container and the gap. The gas channel for gas discharge is also referred to here as a vacuum channel.

An inert gas, also referred to as a protective gas, for example argon, carbon dioxide, nitrogen or a gas mixture, is supplied during the gas supply at least to the container, in particular during filling of the container with food, chemical or pharmaceutical products, in order to create a protective gas atmosphere inside the container. In an embodiment, an inert gas is supplied in this case to the gap too, so that the container is surrounded by a protective gas atmosphere when the jacketing is removed. In an embodiment, the container is transported to a closing device after removal of the jacketing, wherein at least a top area of the open container is kept in a protective gas atmosphere, for example inside a tunnel and/or in a laminar flow. In other embodiments, the filling head and the closing device are enclosed in a common housing or in housings communicating with one another inside which a protective gas atmosphere prevails.

In some embodiments, it is provided that negative pressure is continuously generated inside the container and the gap in the filling phase, wherein a continuous product discharge is made to equalize the negative pressure inside the container.

In an embodiment, an end of the gas channel having the container opening is immersed into the container in the filling position.

The free end of the filling channel projects into the container with an immersion depth in the filling position. During a product discharge effected by the generation of a negative pressure inside a container, filling takes place to a defined filling level which depends in particular on an immersion depth of a filling channel of the filling head into the container.

In other words, the immersion depth determines a filling level of the product filled into the container during the filling phase. In particular, the free end of the filling channel projects in some embodiments into the container over the entire filling phase with a fixed immersion depth. However, embodiments are also conceivable in which an immersion depth is continuously or gradually reduced during the filling phase, so that a distance of the free end from an already filled product is at least kept constant within at least a tolerance range at least during one section of the filling phase. The filling level corresponds in this case at least substantially to the immersion depth at the end of the filling phase.

According to the findings of the inventors, due to differing entrapped air in a flowable, powdery product, a density of the filled product and hence a weight of a product filled in the filling phase is subject to variation while the filling level remains the same. By determining the fill weight after filling, and topping up performed before a gassing phase if there is a shortfall from a target weight, it can be ensured that a defined target weight is not fallen short of regardless of a density of the product.

The method thus permits filling of the container and gas exchange inside the filled container with high precision.

In an embodiment, it is provided that at least the filling channel of the filling head is moved relative to the container for topping up, so that the immersion depth of the free end into the container is reduced and a topping-up volume is created inside the container. The product can then flow into the topping-up volume. The immersion depth is reduced, i.e. the filling channel and/or the container is/are moved such that a distance of the free end of the filling channel from an end opposite a filling opening of the container is enlarged. This creates a topping-up volume. A movement distance of the filling head is determined depending on the topping-up volume to be provided, wherein this in turn depends on the difference between the determined fill weight and the target weight, also referred to as the differential weight. In some embodiments, a medium density of the filled product is assumed for topping up. A topping-up volume is then the quotient from the differential weight and the density. With a constant cross-section of the container over its height, the movement distance corresponds to the quotient from the topping-up volume and the base area of the container. In some embodiments, the filling channel and/or the entire filling head are moved upwards in a direction away from a filling opening arranged on the top of the container. In an embodiment, a gas-tight connection of the filling head to the container is maintained during topping up.

A total or gross weight of the filled product and of the container is referred to as the fill weight.

In an embodiment, a tare weight of the container is determined before the filling phase. By determining the tare weight of the container, also referred to as the empty weight of the container, weight variations of the container can be taken into account when the fill weight is determined and when the target weight is defined, so that it is assured that a weight of the filled product, also referred to as the net weight, does not fall short of a defined target value regardless of weight variations of the container.

Determining of the tare weight is performed before a filling phase. Determining of the tare weight is performed in this case in particular before generation of a negative pressure in the container and in the gap. The fill weight is however determined before the gassing phase, hence with a negative pressure prevailing inside the container and the gap. In some embodiments, a pressure difference is determined when the tare weight and the fill weight are determined, and taken into account for example as a disturbance variable and/or calibration value when the fill weight is determined.

In an embodiment, it is provided that the container rests on a bottom element in the filling phase, wherein a load cell of the weighing device is provided at the bottom element. In some embodiments, a lower open end of the jacketing is sealed by the bottom element, wherein the bottom element is lifted in the direction of the jacketing and/or the jacketing is lowered in the direction of the bottom element to close the jacketing, depending on the specific application. The load cell arranged at the bottom element permits determining of the tare weight and of the fill weight. In some embodiments, the container is set onto the bottom element before the filling phase and remains on the bottom element after the filling phase until completion of the gassing phase.

In an embodiment, negative pressure is generated up to a first pressure level in the filling phase, and before the gassing phase negative pressure up to a second pressure level below the first pressure level is generated for degassing the container in a degassing phase.

By generating the negative pressure up to the second pressure level below the first pressure level, any air present in the container after the filling process or any other gas present in the filled container is removed. This process is also referred to as degassing. Degassing takes place directly following the filling operation without changing the system. In particular, the fact that the product is in a loosened state due to the filling process can be advantageously used so that degassing is possible in one step in advantageous embodiments, instead of in several steps with differing pressure levels as is usual in conventional devices for degassing.

In an embodiment, two negative pressure sources are provided, in order to generate a negative pressure with a first pressure level and a negative pressure with a second pressure level. In other embodiments, it is provided that the gas channel has a bypass opening to its surroundings, wherein the bypass opening is closed for the degassing phase subsequent to the filling phase. By closing the bypass opening, a second pressure level for degassing can thus be generated using the negative pressure source used for product discharge at a first pressure level. Movable setting elements such as restrictors or the like inside the gas channel can be dispensed with.

In an embodiment, after the filling phase and before a gassing phase, a pressure level inside the container and the gap is kept at a constant pressure level in a rest phase for settling the product. What is achieved by this is that the air trapped in the product is removed not only from a top area, but also from lower-lying regions of the container during subsequent degassing. Any topping up of the product that may be necessary takes place, depending on the specific application, before or after the rest phase or as an interruption of it.

According to a second aspect, a device for filling a container open at the top with a flowable product, in particular with coffee powder or with milk powder, is provided, comprising a filling head and a gas-tight jacketing receiving the container in the filling position, wherein the filling head comprises a filling channel having a free end and a gas channel having a container opening and a connection opening; wherein the free end of the filling channel projects into the container with an immersion depth in the filling position; wherein in the filling position gas is dischargeable out of the container and suppliable to the container via the gas channel; wherein the jacketing adjoins the filling head and/or the container in sealing manner at least in the filling position in order to provide a gas-tightly closed gap between the jacketing and the outer container wall; wherein a gap connection opening is provided; wherein gas is dischargeable out of the gap and gas is suppliable to the gap via the gap connection opening; wherein a control device is provided which is configured to connect fluidically the container and the gap to a negative pressure source in a filling phase such that negative pressure is generatable inside the container and the gap; wherein the negative pressure in the container effects a product discharge via the filling channel up to a filling level at least substantially corresponding to the immersion depth; wherein the control device is configured to connect fluidically the container and the gap to a gas source after the filling phase in a gassing phase such that a gas is suppliable to the container and the gap; wherein an inert gas is suppliable in the gassing phase at least to the container; wherein a weighing device is provided for determining a fill weight of the container; wherein the control device is further configured to determine a fill weight of the container after the filling phase and before the gassing phase and compare it with a target weight, and to effect topping up if the determined fill weight is below the target weight.

A device with which states of the device are determinable and selectively influenceable is referred to as a control device. The control device comprises in some embodiments several control units with which one state or several states is/are determinable and/or influenceable. The control device comprises in some embodiments electronic and/or pneumatic control units, with which valves provided at the connection opening of the gas channel and at the gap connection opening can be opened or closed. In other embodiments, a mechanical control unit is alternatively or additionally provided. In an embodiment, the mechanical control unit comprises a setting element movable relative to the filling head, wherein depending on a positioning of the filling head relative to the setting element, the connection opening is connected fluidically to the negative pressure source or to the gas source or disconnected therefrom and in particular sealed. In an embodiment, the setting element is a setting disc provided on a carousel, wherein the filling head is moved along the circumference of the setting disc. The use of a mechanical control unit permits a valve-free design for a gas discharge and/or a gas supply.

In some embodiments, the control device also comprises an electronic control unit for evaluating a determined fill weight and for initiating topping up.

In an embodiment, the jacketing is movable relative to the filling head, wherein the jacketing is moved to the filling head in the filling position and is in sealing contact therewith. In other embodiments, the jacketing is designed in one piece with the filling head. In an embodiment, the jacketing and the filling head are manufactured separately from one another and are connected to one another in gas-tight manner. In other embodiments, the jacketing and the filling head are made as an integral component.

In an embodiment, a separate negative pressure source or a separate gas source is provided for degassing and/or gassing of the gap, wherein the gap is connectable fluidically to the separate negative pressure source or to the separate gas source via the gap connection opening. In other embodiments, the gap connection opening opens into the gas channel. The gap and the container are connectable fluidically to a common negative pressure source or to a common gas source respectively via the gas channel.

In some embodiments, the device comprises an actuator which is configured to move at least the filling channel of the filling head relative to the container for topping up, in order to reduce the immersion depth of the free end into the container and to create a topping-up volume inside the container. For a reduction of the immersion depth, the container and/or the filling channel is movable using the actuator, so that a distance of the free end from a closed end of the container opposite to the filler opening of the container is enlarged. In some embodiments, it is provided in particular that at least the filling channel or the entire filling head is lifted by the actuator for topping up. A product to be filled then flows into the topping-up volume created. For a movement of the filling channel, the actuator is operated using the control device in some embodiments. A movement distance of the filling head is determined in this case—as described above—depending on the topping-up volume to be provided, wherein this in turn depends on the difference between the determined fill weight and the target weight, also referred to as differential weight.

In some embodiments, the filling channel moves relative to the container in particular such that the filling head is in sealing contact with the container during topping up.

In some embodiments, the control device is furthermore configured to determine a tare weight of the container with the weighing device before the filling phase. The control device is in this case preferably configured to determine a weight of the filled product based on the fill weight and tare weight.

In some embodiments, the weighing device comprises a load cell, wherein a bottom element is provided on which the container rests in the filling phase, and wherein the load cell is provided at the bottom element. The load cell is arranged into a surface of the bottom element facing the container or underneath the bottom element, depending on the embodiment.

According to a third aspect, a carousel is provided comprising positions distributed over the circumference and at each of which a device with a filling head and with a jacketing is provided. A device with a rotor rotating continuously or timed about a rotary axis is referred to as a carousel, wherein the positions are moved with the rotor along a circle. In some embodiments, a weighing device is provided in this case at each position, with which a fill weight and if applicable also a tare weight is determinable. In other embodiments, at least one stationary weighing device is provided, wherein the positions are moved by the weighing device for determining the fill weight.

In some embodiments, some of the positions are moved along a guide track with the rotation of the rotor, to effect lowering of the jacketing relative to a bottom element and/or lifting of the bottom element relative to the jacketing for sealing of the devices after an insertion of a container, or lifting of the jacketing relative to a bottom element and/or lowering of the bottom element relative to the jacketing to open the devices for removal of the container.

In some embodiments of the carousel, the gas channel is connected to a negative pressure source or to a gas source for a gas discharge and a gas supply by a rotation of the rotor. In other embodiments, valves are provided which are opened or closed due to a rotation and/or due to control signals of the control device.

BRIEF DESCRIPTION OF THE DRAWINGS

Further advantages and aspects of the invention are revealed by the claims and by the following description of preferred exemplary embodiments, which are explained below with reference to the figures: The drawing shows in:

FIG. 1 an embodiment of a device for filling a container open at the top with a flowable product;

FIG. 2 a starting position of a method for filling a container open at the top with a flowable product;

FIG. 3 a first phase of the method for filling of the container open at the top, wherein the container is moved into a filling position;

FIG. 4 a second phase of the method, wherein the container is being filled;

FIG. 5 a third phase of the method, wherein a pressure level is kept constant to settle the product;

FIG. 6 a fourth phase of the method, wherein a pressure level is further lowered for degassing of the product;

FIG. 7 a fifth phase of the method, gassing of the container with an inert gas takes place;

FIG. 8 a sixth phase of the method, wherein bridging takes place at a filling channel by the application of a negative pressure;

FIG. 9 a seventh phase of the method, wherein the container is removed from the device; and

FIG. 10 a carousel with several devices for filling containers.

DETAILED DESCRIPTION OF THE EXAMPLES

FIG. 1 shows an embodiment of a device 1 for filling a container open at the top 2 with a flowable product, in particular with coffee powder or with milk powder.

The device 1 comprises a filling head 3 with a filling channel 30 having a free end 300 and with a gas channel 32. The gas channel 32 comprises a section surrounding the filling channel 30 in annular manner, at the free end of which section a container opening 320 is provided. A gas-permeable closure element 326 for product retention is provided at the container opening 320. The closure element 326 is for example a metal grille or a component made of a porous material.

In the embodiment shown, a section 301 of the filling channel 30, which adjoins the free end 300 with the outlet opening, is also designed gas-permeable, such that when a negative pressure is generated inside the gas channel 32 the flowable product can be drawn onto an inner wall of this section 301 of the filling channel 30 to form a bridge, as described further below.

The gas channel 32 shown has a first connection opening 321 for connection to a negative pressure source, not shown, and a second connection opening 322 for connection to a gas source, not shown. In a modified embodiment, only one connection opening is provided instead of the two connection openings 321, 322 and is connectable fluidically to the negative pressure source or to the gas source depending on the phase. A bypass opening 323, via which the gas channel 32 is connectable fluidically to the surroundings, is further provided on the gas channel 32.

In a filling position shown in FIG. 1, the container 2 adjoins the filling head 3 in gas-tight manner with a sealing element 4, such that gas is dischargeable out of the container 2 via the gas channel 32. For that purpose, the first connection opening 321 for example is connectable to a negative pressure source, not shown, such as a vacuum pump. Gas is also suppliable to the container 2 via the gas channel 32, wherein the second connection opening 322 is connectable to a gas source, not shown, in particular to an inert gas supply.

A bottom element 5, which supports the container 2 from underneath and which is movable relative to the filling head 3, as shown schematically by a double arrow, is provided in the example shown for movement of the container 2 relative to the filling head 3. In some embodiments, the device 1 is part of a carousel 8, shown in FIG. 10, with several positions 82, wherein the bottom element 5 is lifted relative to the filling head 3 when the carousel 8 is rotated, so that an upper open end of the container 2 contacts the filling head 3 in sealing manner. In another embodiment, the filling head 3 is lowered relative to the bottom element 5, such that an upper open end of the container 2 contacts the filling head 3 in sealing manner.

The device 1 comprises a weighing device 7, wherein a tare weight of the container 2 before filling and a fill weight of the container 2 after filling are determinable with the weighing device 7. The weighing device 7 comprises in the example, shown schematically, a load cell 70 provided at the bottom element 5.

The device 1 further comprises a gas-tight jacketing 6, which receives the container 2 in the filling position shown in FIG. 1. In the example shown, the jacketing 6 is designed in one piece with the filling head 3. The jacketing 6 is formed for example as a separate component and is connected undetachably in gas-tight manner to the filling head 3, for example by soldering, adhesion or welding, or connected detachably in gas-tight manner to the filling head 3 using sealing elements.

The jacketing 6 shown has an open lower end 60, which is sealable in gas-tight manner with the bottom element 5, for example via a seal 65. In this way a gap 62 sealed in gas-tight manner is provided between the jacketing 6 and an outer container wall. In other embodiments, the jacketing 6 is designed in one piece with the bottom element 5 and is connected detachably in gas-tight manner to the filling head 3 and/or to the container 2.

The gap 62 is connected to the gas channel 32 via a gap connection opening 64, so that gas is dischargeable from the gap 62 and gas is suppliable to the gap 62 via the gap connection opening 64. In other embodiments, the gap connection opening 64 is provided on the bottom element 5 and/or on a cover of the jacketing 6 that adjoins the filling head 3. The connection of the gap 62 to the gas channel 32 permits simultaneous degassing and gassing of an interior of the container 2 and of the gap 62 surrounding the container 2 using a common negative pressure source or a common gas source. In other embodiments, an additional negative pressure source and/or an additional gas source is provided for the gap 62.

A control device 9 is provided for a phase-dependent connection of the gas channel 32 to the negative pressure source or to the gas source. The control device 9 is coupled wired or wirelessly to the weighing device 7 for exchanging data, wherein the data determined by the weighing device 7 is evaluated by the control device 9 and if a fill weight determined falls short of a target weight.

In some embodiments the control device 9 comprises an electronic control unit. A connection of the gas channel 32 to the negative pressure source or to the gas source is effected by the electronic control unit, wherein valves provided at the connection openings 321, 322 can be opened or closed by the control unit.

In other embodiments, the control device comprises a mechanical control unit with a setting disc, wherein the setting disc and the filling head are movable relative to one another. Depending on a positioning of the filling head 3 relative to the setting disc, the connection openings 321, 322 are connected to the negative pressure source or to the gas source or disconnected therefrom and in particular closed by the setting disc. The setting disc is further designed such that depending on a positioning of the filling head 3 relative to the setting disc, the bypass opening 323 is opened for a fluidic connection of the gas channel 32 to the surroundings, or closed for its disconnection. The use of a mechanical control device permits a valve-free design for degassing and/or gassing.

A method for filling the container 2 using the device 1 is described in the following with reference to FIGS. 2 to 10.

FIG. 2 shows a starting position of the method, wherein the filling head 3 is arranged above the container 2 at a distance therefrom. A connection to the negative pressure source via the first connection opening 321 and a connection to the gas source via the second connection opening 322 are interrupted, as shown schematically by crosses. The gas channel 32 may be connected to the surroundings via the bypass opening. The connection is also interrupted in other embodiments.

FIG. 3 shows schematically a first phase of the method, in Zone Il in FIG. 10, wherein the container 2 is lifted in the direction of the filling head 3 by the bottom element 5 and moved into the filling position. In the filling position, the open end of the container 2 is sealed in gas-tight manner by the filling head 3. The container 2 is inserted into the jacketing 6 and the open lower end of the jacketing 6 is sealed by the bottom element 5. The movement of the bottom element 5 in the direction of a filling head 3 arranged at a constant level is advantageous for simplicity in the design of the gas supply and gas discharge. Designs are however also conceivable in which the filling head 3 is lowered in the direction of the bottom element 5. After lowering of the filling head 3 onto the container 2, a tare weight of the container 2 is determinable by the weighing device 7. Determining the tare weight is performed in Zone III according to FIG. 10. In some embodiments, any weight forces applied to the weighing device 7 by the filling head 3 are also determined and are taken into account in the tare weight of the container 2.

FIG. 4 shows schematically a second phase of the method, the filling phase, in Zone IV in FIG. 10, wherein the container 2 is filled. For that purpose, the gas channel 32 is connected via the first connection opening 321 to a negative pressure source, not shown. Negative pressure is generated inside the container 2 or the gap 62 using the negative pressure source, via the container opening 320 of the gas channel 32 and via the gap connection opening 64 respectively. The connection of the gas channel 32 to the surroundings via the bypass opening 323 remains open here, so that negative pressure is set at a first pressure level. The negative pressure inside the container has the effect that the flowable product is drawn into the container 2 via the filling channel 30. The gas-permeable closure element 326 at the container opening 320 prevents the product getting into the gas channel 32.

Filling takes place up to a maximum filling level shown in FIG. 5, corresponding to an immersion depth of the free end 300 of the filling channel 30 into the container 2.

After completion of the filling phase, a fill weight of the container 2 is determinable by the weighing device 7, in Zone V in FIG. 10. In some embodiments, any weight forces applied to the weighing device 7 by the filling head 3 are also determined and are also taken into account in the fill weight of the container 2. In some embodiments, a difference in the pressure is determined when determining the fill weight in comparison to a pressure when determining the tare weight, and taken into account during determination.

The fill weight can be compared to a target weight using the control device 9 (see FIG. 1). In some embodiments, the target weight is a target net weight of the filled product, wherein the determined tare weight is subtracted from the determined fill weight or the determined tare weight is added to the target weight for the comparison.

FIG. 5 shows a third phase of the method after the end of product filling, also referred to as the rest phase, in Zone VI in FIG. 10, wherein a pressure level is kept constant for settling of the product inside the container 2. The connection opening 321 remains open in an embodiment.

If the comparison of the fill weight with the target weight in Zone V according to FIG. 10 indicates that the fill weight is below the target weight, topping up is possible before, during or after the rest phase, wherein for that purpose the filling channel 30 is moved relative to the container 2 using an actuator 90 shown schematically in the example shown, so that an immersion depth of the first end into the container 2 is reduced and a topping-up volume is created inside the container 2 in this way. In the example shown, the entire filling head 3 is moved upwards for topping up, as shown schematically by an arrow in FIG. 5. This movement during topping up is within a tolerance range, so that during a movement of the filling head 3 relative to the container 2 the gas-tight contact of the filling head 3 with the container 2 and also a gas-tight connection of the bottom element 5 to the jacketing 62 are maintained. In other embodiments, only the filling channel 30 is moved relative to the container 2 using an actuator. In yet other embodiments, the container 2 is alternatively or additionally moved relative to the filling channel 30 or to the entire filling head 3 using an actuator.

FIG. 6 shows a fourth phase of the method, also referred to as degassing phase, in Zone VII in FIG. 10, wherein a pressure level is further lowered for degassing of the product filled into the container 2. For that purpose, the bypass opening 323 is closed in the example shown, so that in the case of a connection of the gas channel 32 to the negative pressure source via the first connection opening 321 a second pressure level, which is below the first pressure level during the product discharge (cf. FIG. 4), is generated inside the container 2 and the gap 62 surrounding the container. A simultaneous pressure reduction inside the container 2 and the gap 62 around the container 2 prevents the container 2 from collapsing due to an applied negative pressure.

FIG. 7 shows a fifth phase of the method, also referred to as gassing phase, in Zone VIII in FIG. 10, wherein the container 2 is gassed with an inert gas. For that purpose, the first connection opening 321 is disconnected from the negative pressure source and the second connection opening 322 is connected fluidically to the gas source. Since the gap 62 is connected fluidically to the gas channel 32 via the gap connection opening 64, the gap 62 too is gassed with the inert gas. In other embodiments, a different gas than that in the container 2 is supplied to the gap 62 via a separate gas source.

FIG. 8 shows a sixth phase of the method, in Zone IX in FIG. 10, wherein negative pressure is again applied for forming a bridge at an outlet opening 300 of the filling channel 30.

Formation of a stable arch-like structure in the region of an outlet opening 300 of the filling channel due to adhesive forces between individual particles of the product is referred to as bridging in connection with the application.

Application of the negative pressure for bridging is achieved via the gas channel 32 used for degassing and gassing in the example shown. The first connection opening 321 is again connected fluidically to the negative pressure source. Due to the applied negative pressure, particles of the product present in the filling channel 30 are drawn onto the gas-permeable section 301 of the filling channel 30. As a result, a so-called bridge forms at the outlet opening of the filling channel 30, preventing a further product discharge when the container 2 is separated from the filling head 3. This allows filler valves, flaps or the like to be dispensed with at the filling head 3. The negative pressure is applied for a sufficiently short period for bridging such that drawing of the product out of the container 2 is at least reduced to a tolerable extent.

In an alternative embodiment, not shown, a chamber surrounding the gas-permeable section 301 is provided, via which negative pressure for bridging is applicable to the gas-permeable section 301. In an embodiment, the chamber has a connection opening, not opening into the gas channel 32, for a negative pressure source. The chamber is degassed or evacuated via the separate connection opening, without the product being drawn out of the container 2 via a container opening of the gas channel.

FIG. 9 shows a seventh phase of the method, in Zone X in FIG. 10, wherein the container 2 is removed from the device 1. To do so, the bottom element 5 with the container 2 set thereon is lowered relative to the filling head 3. The container 2 can then be supplied to a closing device, not shown.

The device 1 is, in advantageous embodiments, at a position of a carousel with several positions, each having one device 1 according to FIGS. 1 to 9.

FIG. 10 shows a carousel 8, schematically in a plan view. The carousel 8 has a turntable 80 rotating about a rotary axis A and several positions 82, 24 in number in the example shown, distributed evenly over the circumference, wherein one device 1, each with a filling head 3 (cf. FIGS. 1 to 9), is provided at each position 82 according to FIGS. 1 to 9. The turntable 80 can be rotated about the rotary axis A for a movement of the positions 82 in a timed or continuous manner. For loading and unloading, inlet and outlet wheels 84, 86 are provided in the example shown, which rotate synchronously with the carousel 8 in order to transfer one container 2 (cf. FIGS. 1 to 9) to a position 82 or to remove a container 2 from a position 82 respectively. Other devices for loading and unloading are however also conceivable. Loading and unloading takes place in a Zone I in FIG. 10.

A carousel 8 permits a continuous process, wherein the various process steps of the method according to FIGS. 2 to 9 are performable distributed over the circumference of the carousel 8. In the example shown, ten Zones I to X are provided on the carousel 8 for that purpose.

In a first Zone I of the carousel 8, loading of the carousel 8 with containers 2 or unloading takes place. The containers 2 supplied to the carousel 8 are transported after loading, by rotation of the carousel 8, and pass through further Zones Il to X in the example shown.

In a second Zone Il following the first Zone I in a rotation direction indicated by an arrow, the bottom elements 5 with the containers 2 are lifted in the direction of the filling head 3 as shown in FIG. 2. The positions 82 are, during lifting of the container 2 in the direction of the filling head 3, in each case closed off from the surroundings using the jacketing 6 connectable to the bottom element 5 in sealing manner (cf. FIGS. 2 and 3).

Then a tare weight of the container 2 with the filling head 3 set thereon is determined in Zone III. The Zone III is limited to exactly one angle setting of the position 82 in the case of a timed movement of the carousel, or to a comparatively small angle range in the case of a continuous movement. In some embodiments, the tare weight is determined using the weighing device 7 provided at the position 82. In other embodiments, a weighing device is provided stationarily at the carousel 8.

After determining the tare weight, the container 2 is filled in Zone IV, as shown in FIG. 4. After filling, a fill weight of the container 2 with the filling head 3 set thereon is determined in Zone V. Zone V is also limited to exactly one angle setting of the position 82 in the case of a timed movement of the carousel, or to a comparatively small angle range in the case of a continuous movement. In some embodiments, the fill weight is determined using the weighing device 7 provided at the position 82. In other embodiments, a weighing device is provided stationarily at the carousel 8.

This is followed by settling of the filled product in Zone VI as shown schematically in FIG. 5. If comparison of the determined fill weight with a target weight shows that topping up is required, this topping up also takes place in Zone VI.

In the following Zone VII, degassing as shown in FIG. 6 takes place. In a following Zone VIII, gassing with an inert gas as shown in FIG. 7 takes place.

In Zone IX, negative pressure is again applied for bridging at an outlet opening of the filling channel 30 (cf. FIG. 8), as shown schematically in FIG. 8.

In a final Zone X, the bottom elements 5 with the containers 2 are, as shown in FIG. 9, lowered relative to the filling head 3, so that the containers 2 are then removable from the carousel 8.

Finally, the containers are ejected in the first Zone I and supplied for example to a closing device, not shown, for sealing the containers.

The carousel 8 is also used here as a mechanical control device, wherein a fixed setting disc, not visible in FIG. 10, is provided on the carousel 8. With the rotation of the turntable 80 of the carousel 8, the devices 1 provided at the positions 82 are moved relative to the setting disc, wherein the connection openings 321, 322 are connected to the negative pressure source or to the gas source or are disconnected therefrom, depending on a positioning of the filling head 3 of the respective device 1 relative to the setting disc. The setting disc is further designed here such that the bypass opening 323 is opened for a fluidic connection of the gas channel 32 to the surroundings or closed for its disconnection, depending on a position of the filling head 3 relative to the setting disc. The setting disc has the effect in this way that negative pressure with a first pressure level is generated inside the container 2 and the gap 62 for filling the containers in Zone IV, and negative pressure up to a second pressure level below the first pressure level is generated inside the container 2 and the gap 62 for degassing in Zone VII.