Automatic packaging unit filling and sealing containers made of heat-sealable material and method for operating such a unit

Abstract

An automatic packaging unit for filling and sealing containers made of heat-sealable material comprises a conveyor (4) rotating about an axis (X), a filling member (6), mounted on the conveyor (4) to follow a first closed trajectory (T1) about said axis (X), an ultrasonic sealing device (7), mounted on the conveyor (4) to follow a second closed trajectory (T2) about said axis (X) at a smaller distance from said axis (X) with respect to said first trajectory (T1), and a gripping head (8), mounted on the conveyor (4) to follow a third closed trajectory (T3) about said axis (X), the gripping head (8) having partially radial movement arranged to transfer a container between the first trajectory (T1) and the second trajectory (T2).

Description

[0001] AUTOMATIC PACKAGING UNIT FILLING AND SEALING CONTAINERS MADE OF HEAT-SEALABLE MATERIAL AND METHOD FOR OPERATING

[0002] SUCH A UNIT

[0003] Technical field

[0004] The present invention relates to the technical field of automated machines for making containers containing a preset amount of product, for example, an incoherent product (granular, powders or the like) or liquid / semi-liquid product. Such containers are particularly of the type having an upper seal, bags or cartons or others, for example.

[0005] Background art

[0006] In such machines, there is usually provided a rotating conveyor that receives a sequence of empty bags in a feeding station, transports them in a circular filling section and seals and releases them in a releasing station. To this end, the conveyor mounts a sequence of filling devices, mutually angularly distributed about the rotation axis of the conveyor, and a plurality of sealing devices, also angularly distributed about the axis of the conveyor. A machine of this type is described in Patent Application EP3395698, for example. Such a conveyor is configured so that, during the filling, each bag follows an outer trajectory, farther from the rotation axis, and so that such a bag is subsequently radially moved towards the rotation axis to follow an innermost sealing trajectory. In order to allow a correct sealing of the upper flaps of the bag defining the opening, each sealing device is made by means of a pair of sealing bars movable in a symmetric manner between a disengaged position, raised and spacedapart, and a sealing position, lowered and approached, in which they compress and seal such upper flaps of the bag. The sealing bars are equipped with respective heating members for defining a heat seal. Such a raised disengagement position with respect to the upper flaps of the bar is necessary to allow the radial movement of the bag in the passage from the first, radially outermost, filling trajectory to the second, radially innermost, sealing trajectory.

[0007] The Applicant has found that various aspects of such a solution can be improved.

[0008] A first aspect relates to productivity: the hot sealing requires minimum execution times which cannot be reduced, associated with the heatsealing properties of the material, and therefore which cannot be reduced unless incomplete or non-conforming seals are created.

[0009] A second aspect relates to the possibilities of use: heat sealing generates heat which may alter the physical-chemical properties of the product content in the bag and therefore, may limit the use of such a filling and sealing system to products not susceptible to alteration following heating.

[0010] A third aspect relates to the performance complexity and cost: heat sealing requires immediately cooling the bag to remove heat from the heating area: in addition to penalizing the minimum times and therefore further limiting productivity, this introduces complex and voluminous cooling systems which introduce the need to enlarge the radial size of the conveyor (and therefore costs and dimensions) or, dimensions being equal, to reduce the number of devices on board the conveyor (further reduction in productivity).

[0011] In this context, the Applicant has found that by performing ultrasonic sealing, a simplified structure is obtained not requiring means for heating and cooling the material; further, this allows the production speed, and therefore the overall productivity, to be increased. Further, the absence of heating makes the machine suitable for operating with different types of products, including products susceptible to alteration in the event of heating, since ultrasonic sealing does not involve heating the container, and therefore the contents.

[0012] The Applicant has also found that ultrasonic sealing is easily implementable also in existing sealing wheels where the trajectory of the filling nozzles is radially outermost with respect to the trajectory of the sealers. Such a condition is very important for counteracting the accumulation of dirt and residue from the sealing area, since the filling nozzles are subject to formation of accumulations of material in the underlying area, such accumulations damaging the sealing because the inclusion thereof in the sealing area may jeopardize the proper formation of an airtight seal. Therefore, it is very important to separate the two trajectories from each other.

[0013] Object of the invention

[0014] Therefore, in a first aspect thereof, the present invention relates to an automatic packaging unit for filling and sealing containers made of heat- sealable material.

[0015] Preferably, the unit comprises a conveyor defining a closed transport path which develops about an axis.

[0016] Preferably, the unit further comprises a station for feeding containers, configured to feed the conveyor with a sequence of containers to be filled.

[0017] Preferably, the unit further comprises a station for releasing the containers, configured to receive a sequence of filled and sealed containers from the conveyor.

[0018] The unit further comprises at least one filling member mounted on the conveyor to perform the filling of a container supported by the conveyor.

[0019] Preferably, the at least one filling member is mounted on the conveyor so as to follow, during the movement of the conveyor, a first closed trajectory about the axis.

[0020] The unit further comprises at least one sealing device, mounted on the conveyor to perform a sealing of the filled container, in particular in a top area of the container.

[0021] Preferably, the at least one sealing device is mounted on the conveyor so as to follow, during the movement of the conveyor, a second closed trajectory about the axis. The unit further comprises at least one gripping head, mounted on the conveyor to hold a respective container at least during filling and sealing.

[0022] Preferably, the at least one gripping head is mounted on the conveyor so as to follow, during the movement of the conveyor, a third closed trajectory about the axis.

[0023] Preferably, the second trajectory is kept at a smaller distance from the axis with respect to the first trajectory. In other words, the second trajectory is radially innermost with respect to the first trajectory.

[0024] Preferably, the gripping head is mounted on the conveyor so as to have, with respect to the conveyor, an at least partially radial movement with respect to the axis so as to define an approaching and distancing movement with respect to the axis.

[0025] According to the invention, the sealing device is an ultrasonic sealing device.

[0026] Advantageously, the automatic packaging unit according to the invention has increased productivity due to the ultrasonic sealing, which has low performance times and does not require heat transition times (heating / cooling).

[0027] Further, the absence of special heating and cooling systems results in a significant structural simplification with a reduction of the dimensions, or, dimensions being equal, the installation of an increased number of sealers.

[0028] Further, the absence of special heating systems makes the unit suitable for operating with products susceptible to physical-chemical alteration with the heating.

[0029] In a second aspect thereof, the present invention relates to a method for operating the aforementioned automatic packaging unit.

[0030] Preferably, the method comprises feeding a container which is open at the top to the conveyor by means of the feeding line.

[0031] Preferably, the method comprises gripping the container by means of a gripping head arranged on the conveyor. Preferably, the method comprises introducing a pre-portioned amount of material into the container supported by the gripping head.

[0032] Preferably, the method comprises radially moving the container by means of the gripping head to bring the container from the first closed trajectory to the second closed trajectory.

[0033] Preferably, the method comprises engaging and sealing the upper flaps of the filled container by means of the sealing device, creating an ultrasonic seal of the upper flaps of the container.

[0034] Preferably, the method comprises picking the filled and sealed container from the gripping head by means of the receiving line.

[0035] Preferably, the container is made by means of two or more layers of film at least at an area of the container subjected to the ultrasonic sealing.

[0036] In an embodiment, the container is a bag.

[0037] In a different embodiment, the container is a prismatic receptacle made of a multi-layer material, a laminated (in particular, food) material, for example.

[0038] In at least one of the above aspects, the present invention can also have at least one of the preferred features set forth below.

[0039] Preferably, the sealing device comprises a sonotrode and an anvil mutually movable along an at least partially radial trajectory with respect to the axis between an opening configuration, with disengagement between said sonotrode and anvil, and a closing configuration, suitable for sealing a container supported by a respective gripping head.

[0040] Preferably, the mutual movement trajectory between sonotrode and anvil lies on a plane perpendicular to the axis.

[0041] Preferably, the mutual movement trajectory between sonotrode and anvil is straight.

[0042] More preferably, the mutual movement trajectory between sonotrode and anvil is perpendicular to the axis.

[0043] Preferably, such a mutual movement between sonotrode and anvil is achieved by moving at least the anvil between the two configurations. Preferably, the sonotrode is kept stationary with respect to the conveyor, preferably at an adjustable distance with respect to the axis, while the anvil is movable towards and away from the sonotrode to achieve the aforesaid opening and closing configurations.

[0044] However, the sonotrode may in any case be adjustable in radial direction, for example, according to the format to be processed.

[0045] In an embodiment, such a mutual movement between sonotrode and anvil is performed by moving also the sonotrode, in particular in radial direction. Preferably, the sonotrode is arranged in radially innermost position with respect to the axis so as to have a corresponding active sealing surface facing the outside, while the anvil is arranged in radially innermost position with respect to the axis so as to have a corresponding counteracting surface facing the inside.

[0046] Preferably, the sonotrode is aligned along a radial direction perpendicular to the axis. In other words, the aforesaid active welding surface and the respective counteracting surface lie perpendicularly to a radial direction passing through the axis, at least in the closing (sealing) configuration.

[0047] With reference to the movement of the anvil, it is configured to have a movement, between the opening and closing configurations, having at least one radial movement component with respect to the axis and one axial movement component parallel to the axis. Due to such a movement, the anvil may be arranged (in particular in the opening configuration) in such a position so as not to interfere with the radial movement of the container, achieved from the first trajectory to the second trajectory, for bringing the upper flaps of the container to abut, or close to the active sealing surface of the sonotrode.

[0048] Preferably, the axis of the conveyor is vertical or at least partially vertical. In such circumstance, the containers have the filling opening and the corresponding sealing flaps at the top.

[0049] Preferably, the anvil in the opening configuration is raised with respect to the closing configuration. Preferably, the anvil is configured to have a movement, between the opening and closing configurations, along a curved line.

[0050] Preferably, such a curved line lies on a vertical plane, more preferably passing through the axis of the conveyor.

[0051] More preferably, this occurs by means of a rotation movement about a hinge axis or by means of a translation movement along such a curved line or by means of a roto-translation movement along such a curved line.

[0052] Preferably, in the case of rotation movement, the hinge axis is arranged at the top of the anvil in the closing configuration.

[0053] Further, such a rotation preferably has a width, between the opening and closing configurations, comprised between 45° and 120°, preferably comprised between 60° and 105°, and even more preferably comprised between 70° and 90°.

[0054] Preferably, in the case of translation, a special hinged linkage is employed for the anvil, for example, a hinged parallelogram. The anvil is thus mounted on a hinged support oscillating about the hinge axis and the oscillating support is put into rotation about the hinge axis by means of the hinged linkage.

[0055] Preferably, in the case of roto-translation, a special hinged linkage is employed for the anvil, a generically-shaped articulated quadrilateral, for example. Also in this case, the anvil is mounted on an oscillating support hinged about the hinge axis and the oscillating support is put into rotation about the hinge axis by means of the hinged linkage.

[0056] Preferably, the conveyor comprises at least one central body, laterally supporting the at least one gripping head, and at least one respective turret fastened on the central body and arranged at the top of the gripping head.

[0057] Further, preferably the sonotrode is arranged below the turret, while the anvil is mounted on the turret, in particular on a lower portion of the turret. The result is a configuration in which the sonotrode is supported, preferably in a cantilevered manner, in radial direction towards the outside, while the anvil is supported from the top and may reach the closing configuration by descending towards the sonotrode by means of movement along the aforementioned curved line. Such a structure achieves an increased robustness without hindering at the same time the radial movement of the containers from the first trajectory to the second trajectory.

[0058] In other words, the engaging and sealing of the upper flaps of the filled container by means of the sealing device comprises performing a movement of the anvil along the at least partially radial trajectory between the opening configuration and the closing configuration, up to the clamping of the upper flaps between anvil and sonotrode.

[0059] Preferably, the sonotrode is kept stationary with respect to the conveyor.

[0060] In an embodiment, it is provided to adjust the radial positioning of the sonotrode with respect to the axis of the conveyor.

[0061] With reference to the gripping head, it comprises preferably a pair of side grippers configured to engage opposite (vertical) side edges of the container. Such grippers are provided with clamping and releasing movement and are also provided with simultaneous radial movement for transferring the containers from a first, outermost radial position, corresponding to the first trajectory, to a second, innermost radial position, corresponding to the second trajectory.

[0062] Preferably, the conveyor is a conveyor rotating about the axis and the aforementioned first and second trajectories are circular or substantially circular.

[0063] In particular, “substantially circular” means a trajectory that may deviate from a perfectly circular shape in one or more straight sections, each of which, for example, having angular width equal to or less than 120°.

[0064] Preferably, the third trajectory followed by the gripping head comprises at least a first section coincident with the first trajectory, which is intended to fill a container supported by the gripping head, and at least a second section coincident with the second trajectory, which is intended to seal the container. The remaining areas of the third trajectory may be defined by joining areas for such two sections. In the case of first and second circular trajectories, therefore, the third trajectory has at least two sections with circular extension, centered on the axis.

[0065] Preferably, the radial movement of the container by means of the gripping head to bring the container from the first closed trajectory to the second closed trajectory is performed while the anvil is in the opening configuration.

[0066] Preferably, the filling and sealing operations are performed without ever detaching the container from the gripping head. In other words, the gripping head receives the container in the feeding station and holds it for the whole path up to the releasing station.

[0067] Further, preferably the conveyor is operated continuously, in particular at a constant speed.

[0068] Preferably, the unit comprises a plurality of operating modules mounted on the conveyor and angularly distributed about the axis so as to be arranged in sequence along the closed transport path. Each operating module comprises a respective filling member, a respective sealing device and a respective gripping head.

[0069] Preferably, the filling device, the sealing device and the gripping head of each module has a respective actuation system engageable, upon the mounting on the central body of the conveyor, with respective maneuvering members such as to perform a movement of the filling device, the sealing device and the gripping head in an automatic manner following the rotation of the conveyor so that they may always be in phase with one another.

[0070] Preferably, each actuation system is in the form of a maneuvering rod moved by the rotation of conveyor 4 by means of the interaction of a cam follower, applied to the maneuvering rod, with a fixed cam (not shown).

[0071] Brief description of the drawings Further features and advantages of the present invention will be more apparent from the following detailed description of preferred embodiments thereof, made with reference to the accompanying drawings.

[0072] In the drawings:

[0073] - Figure 1 is a plan view of an automatic packaging unit according to the present invention;

[0074] - Figure 2 is a perspective view of the unit in Figure 1 ;

[0075] - Figure 3 is a perspective view of an operating module of the unit in Figure 1 ;

[0076] - Figures 4-6 are sectional views of the module in Figure 3, according to three different operating positions;

[0077] - Figures 4A-6A are enlargements of a detail of the view of Figures 4-6;

[0078] - Figure 7 diagrammatically shows the trajectories followed by the different components of the operating module in Figure 3.

[0079] Detailed description of preferred embodiments of the invention

[0080] With reference to the accompanying figures, reference numeral 1 globally indicates an automatic packaging unit according to the invention. Unit 1 is configured to process containers for incoherent products (powders, grains), products in groups (candies and similar items) or liquid / semi-liquid products. To this end, “containers” means both flexible film containers such as, for example, bags, or rigid or semi-rigid containers made of multilayer (laminated) material, such as cartons, for example. Such containers 100, shown in Figures 4-6, have an upper end provided with a filling opening delimited by opposite upper flaps 110.

[0081] Unit 1 comprises a feeding station 2, configured to feed a sequence of containers 100 to be filled, and a releasing station 3, configured to receive a sequence of filled and sealed containers 100.

[0082] By way of example, the feeding station 2 may be part of a forming line (not shown) that produces the containers starting from a semi-finished product such as, for example, a reel of film material or multi-layer material blanks. Further, by way of example, the releasing station 3 may comprise a hopper for collecting the filled and sealed containers 100 or a line for packaging the filled and sealed containers 100.

[0083] Unit 1 further comprises a conveyor 4 operatively arranged between the stations 2, 3 and configured to receive the containers 100 from the feeding station 2, to process the containers 100 so as to fill and seal them, and to release the filled and sealed containers 100 at the releasing station 3.

[0084] With reference to conveyor 4, it is made in the shape of a conveyor (carousel) rotating about a vertical axis “X”, therefore defining a circular transport path “P”, in particular lying on a horizontal plane.

[0085] Conveyor 4 comprises a central body 4a on which there are mounted, angularly distributed about axis “X”, a plurality of operating modules 5 arranged in sequence along the transport path “P”. Each operating module 5, in the embodiment shown in Figure 3, comprises a rear support 5a that is anchorable to the central body 4a of conveyor 4 and preferably having a plate-like structure.

[0086] Preferably, the operating module 5 further comprises a turret 5b arranged in an upper portion thereof and radially protruding from the rear support 5a.

[0087] A filling member 6, a sealing device 7 and a gripping head 8 are mounted on the rear support 5a.

[0088] With reference to the filling member 6, it comprises a dispensing nozzle 6a which structure is mounted on a vertically movable carriage 6b, by means of a guide 6c applied to turret 5b. The vertical movement of carriage 6b is performed by a linkage 6d associated with a respective actuation system 6e which, in the embodiment shown, is in the form of a maneuvering rod moved by the rotation of conveyor 4 by means of interaction with a fixed cam (not shown). Thereby, during the rotation of conveyor 4, the carriage 6b and therefore nozzle 6a is provided with a periodic raising movement (inactive position) and lowering movement (filling a container 100). The filling member 6, and the nozzle 6a in particular, follows a first trajectory “T1” (Figure 7) centered on the axis and with a circular plan, with an axial component due to the raising and lowering of nozzle 6a.

[0089] With reference to the sealing device 7, it is of the ultrasonic type and comprises a sonotrode 7a and an anvil 7b. Sonotrode 7a and anvil 7b are mutually movable along a radial trajectory, and in particular straight, from and towards axis “X” between an opening configuration (Figures 4 and 5), of mutual disengagement, and a closing configuration (Figure 6), suitable for sealing a container 100.

[0090] Preferably, the mutual movement trajectory between sonotrode 7a and anvil 7b lies in a plane perpendicular to axis “X”.

[0091] More preferably, the mutual movement trajectory between sonotrode 7a and anvil 7b is perpendicular to axis “X”.

[0092] Preferably, such a mutual movement is performed by moving anvil 7b between the two configurations.

[0093] In the embodiment illustrated, sonotrode 7a is kept stationary with respect to conveyor 4, preferably at an adjustable distance with respect to axis “X”, while anvil 7b is movable towards and away from sonotrode 7a to achieve the aforesaid opening and closing configurations.

[0094] Sonotrode 7a is arranged in radially innermost position with respect to anvil 7b, that is to say, in a closer position to axis “X” than anvil 7b. Further, sonotrode 7a has a corresponding active sealing surface “S1” facing outwards, while anvil 7b is arranged in radially outermost position and has a corresponding counteracting surface “S2” facing inwards.

[0095] Preferably, sonotrode 7a is aligned along a radial direction perpendicular to axis “X”. In other words, the active sealing surface “S1” and the respective counteracting surface “S2” lie perpendicularly to a radial direction passing through axis “X”, at least in the closing (sealing) configuration.

[0096] With reference to the movement of anvil 7b, it is configured to have a rotary movement, between the opening and closing configurations, about a hinge axis “Y”. Such a movement, which therefore has an arc-of- circumference trajectory, has a radial movement component with respect to axis “X” and an axial movement component parallel to axis “X” and therefore, of lowering / raising. Due to such a movement, anvil 7b in the opening configuration may be arranged in a raised position such as not to interfere with the upper flaps 110 of container 100 while the latter is moved from the first trajectory “T1” to the second trajectory “T2”, as better described below.

[0097] Further, the hinge axis “Y” is arranged above anvil 7b in the closing configuration.

[0098] Preferably, the rotation of anvil 7b between the two configurations has a width comprised between 45° and 120°, more preferably comprised between 60° and 105°, and even more preferably comprised between 70° and 90°.

[0099] The movement of anvil 7b about the hinge axis “Y” occurs, in the embodiment shown in Figures 4-6, by means of an articulated lever linkage 7c which is connected to anvil 7b (or to an oscillating support 7f thereof) in eccentric position with respect to the hinge axis “Y” and operated, on the side opposite to anvil 7b, by means of a respective actuation system 7d which, in the embodiment shown, is in the form of a maneuvering rod moved by the rotation of conveyor 4 by means of interaction with a fixed cam (not shown). Thereby, during the rotation of conveyor 4, anvil 7b is provided with periodic oscillating movement about the hinge axis “Y” between the two respective configurations.

[0100] Preferably, the rotation of anvil 7b may be subjected to at least one stabilizing spring 7e configured to keep anvil 7b in the opening configuration and / or in the closing configuration. Such at least one spring 7e is preferably active on the articulated lever 7c.

[0101] As shown in Figure 7, the sealing device 7 follows a respective second, circular trajectory “T2” about axis “X”. Such a second trajectory “T2” is inside the first trajectory “T1” and has a smaller diameter than the first trajectory “T1”. Such a second trajectory “T2” is intended as the trajectory followed by the sealing device 7 as a whole.

[0102] With reference to the gripping head 8, it is configured to hold a respective container 100 from the feeding station 2 up to the releasing station 3, as well as during the filling and sealing steps.

[0103] More specifically, the gripping head 8 is mounted on conveyor 4 so as to follow, during the rotation of conveyor 4, a third, closed trajectory “T3” about axis “X” which is not circular in shape.

[0104] In greater detail, as shown in Figures 4-6, the gripping head 8 is mounted on conveyor 4 so as to have, with respect to conveyor 4, a radial movement so as to define an approaching and distancing movement with respect to axis “X”.

[0105] Further, the gripping head 8 comprises a pair of grippers 8a laterally opposed to each other to engage opposite (vertical) side edges of container 100. Such grippers 8a are provided with clamping and releasing movement and are also provided with simultaneous radial movement for transferring the containers 100 from a first, outermost radial position, in which the containers 100 are arranged on the first trajectory “T1”, to a second, innermost radial position, in which the containers 100 are arranged on the second trajectory “T2”.

[0106] In particular, the gripping head 8 follows a third trajectory “T3” extending preferably in a radial region comprised between the first trajectory “T1” and the second trajectory “T2”. In greater detail, the third trajectory “T3” comprises at least a first section coincident with the first trajectory “T1”, intended for filling a container 100 supported by the gripping head 8, and at least a second section coincident with the second trajectory “T2”, intended for welding the container 100. The remaining areas of the third trajectory may be defined by joining areas for such two sections. Such sections have a circumferential trend centered on axis “X”.

[0107] The radial movement of container 100 by means of the gripping head 8 to bring container 100 from the first closed trajectory to the second closed trajectory is performed while anvil 7b is in the opening configuration.

[0108] As shown in Figures 4-6, the gripping head further comprises a first working unit 9, radially movable from and towards axis “X”, and a second working unit 10, radially movable from and towards axis “X” independently of the first working unit 9. One of such working units 9, 10 supports the grippers 8a while the other working unit 10, 9 supports one or more front gripping members, preferably one or more suction cups 11 for achieving a different gripping mode of the containers 100.

[0109] The two working units 9, 10 are independently operable by means of respective actuation systems 12, 13 that, in the embodiment shown, are each in the form of a maneuvering rod moved by the rotation of conveyor 4 by means of interaction with a fixed cam (not shown). Thereby, during the rotation of conveyor 4, the two working units 9, 10 are provided with periodic radial approaching and distancing movements with respect to axis “X”.

[0110] In use, a container 100 is released to conveyor 4 in the feeding station 2 and in particular, gripped by means of the gripping head 8, arranged initially preferably on the first trajectory “T1”. Container 100 is therefore arranged below the filling member 6, which is therefore lowered up to, for example, a partial or complete insertion of nozzle 6a into the container. Once filling has occurred, the filling member 6 is raised and container 100, under the action of the gripping grippers 8a, is brought to the second trajectory “T2” on which a fixed abutment which approaches and compacts the upper flaps 110, preferably acts. Container 100 with the compacted flaps is then subjected to the ultrasonic sealing of the flaps 110 by means of the sealing device 7 and, subsequently, released at the releasing station 3.

[0111] Preferably, the filling and sealing operations are performed without ever detaching container 100 from the gripping head 8. In other words, the gripping head 8 receives container 100 in the feeding station 2 and holds it for the whole path up to the releasing station 3. Further, preferably the conveyor 4 is continuously operated, in particular at constant speed.

[0112] Advantageously, the automatic packaging unit according to the invention has increased productivity due to the ultrasonic sealing, which has low performance times and does not require heat transition times (heating / cooling).

[0113] Further, the absence of special heating and cooling systems results in a significant structural simplification with a reduction of the dimensions, or, dimensions being equal, the installation of an increased number of sealers.

[0114] Further, the absence of special heating systems makes the unit suitable for operating with products susceptible to physical-chemical alteration with the heating.

[0115] Further, the modularity of the conveyor with coupling of each module on common central maneuvering members (fixed cams, for example) allows an accurate and constant timing of the different movable members using a simple and compact structure.

Claims

CLAIMS1. An automatic packaging unit for filling and sealing containers made of heat-sealable material, comprising:- a conveyor (4) defining a closed transport path (P) which develops about an axis (X);- a station (2) for feeding containers (100), configured to feed the conveyor (4) with a sequence of containers (100) to be filled;- a station (3) for releasing the containers (100), configured to receive a sequence of filled and sealed containers (100) from the conveyor (4);- at least one filling member (6) mounted on the conveyor (4) to follow, during the movement of the conveyor (4), a first closed trajectory (T1 ) arranged about said axis (X);- at least one sealing device (7) mounted on the conveyor (4) to follow, during the movement of the conveyor (4), a second closed trajectory (T2) arranged about said axis (X);- at least one gripping head (8) mounted on the conveyor (4) to follow, during the movement of the conveyor (4), a third closed trajectory (T3) arranged about said axis (X); wherein said second trajectory (T2) is kept at a smaller distance from said axis (X) with respect to said first trajectory (T1); wherein said gripping head (8) is mounted on the conveyor (4) so as to have, with respect to the conveyor (4), an at least partially radial movement with respect to said axis (X) so as to define an approaching and distancing movement with respect to the axis (X); and wherein said sealing device (7) is an ultrasonic sealing device.

2. A unit according to claim 1 , wherein said sealing device (7) comprises a sonotrode (7a) and an anvil (7b) which are mutually movable along an at least partially radial trajectory with respect to said axis (X) between an opening configuration, of disengagement between said sonotrode (7a) and anvil (7b), and a closing configuration, suitable for sealing a container(100) supported by a respective gripping head (8).

3. A unit according to claim 2, wherein said sonotrode (7a) is kept stationary with respect to the conveyor (4), preferably at an adjustable distance with respect to the axis (X); the anvil (7b) being movable towards and away from the sonotrode (7a) to achieve said opening and closing configurations.

4. A unit according to claim 2 or 3, wherein the sonotrode (7a) is arranged in radially innermost position with respect to said axis (X), and the anvil (7b) is arranged in radially outermost position with respect to said axis (X), the sonotrode (7a) preferably being aligned along a radial direction perpendicular to said axis (X).

5. A unit according to any one of preceding claims 2 to 4, wherein the anvil (7b) is configured to have a movement, between said opening and closing configurations, having a radial movement component with respect to said axis (X) and an axial movement component parallel to said axis (X).

6. A unit according to claim 5, wherein said axis (X) of the conveyor (4) is vertical or at least partially vertical and wherein the anvil (7b), in said opening configuration, is raised with respect to said closing configuration.

7. A unit according to any one of preceding claims 2 to 6, wherein the anvil (7b) is configured to have a movement, between said opening and closing configurations, along a curved line preferably by means of a rotation movement about a hinge axis (Y) or by means of a translation movement along said curved line.

8. A unit according to claim 7, wherein said curved line lies on a vertical plane preferably passing through the axis (X) of the conveyor (4).

9. A unit according to claim 7 or 8, comprising a hinged linkage (7c) configured to move the anvil (7b) along said curved line.

10. A unit according to any one of preceding claims 7 to 9, wherein the movement of the anvil (7b) along said curved line is carried out by means of a rotation about a hinge axis (Y) arranged above the anvil (Y) in the closing configuration.

11. A unit according to claim 10 when dependent on claim 9, wherein the anvil (7b) is mounted on an oscillating support (7f) hinged about said hinge axis (Y) and wherein the oscillating support (7f) is put into rotation about the hinge axis (Y) by means of said hinged linkage (7c).

12. A unit according to claim 10 or 11 , wherein said rotation has a width, between the opening and closing configurations, comprised between 45° and 120°, preferably comprised between 60° and 105°, and more preferably comprised between 70° and 90°.

13. A unit according to any one of preceding claims 2 to 12, wherein the conveyor (4) comprises a central body (4a) laterally supporting said at least one gripping head (8), and at least one respective turret (5b) mounted on the central body and arranged above said gripping head (8), and wherein the sonotrode (7a) is mounted on the central body (4a) below said turret (5b) while the anvil (7b) is mounted on said turret (5b).

14. A unit according to any one of the preceding claims, wherein said first trajectory (T1 ) and second trajectory (T2) are circular or substantially circular.

15. A unit according to any one of the preceding claims, comprising aplurality of operating modules (5) mounted on the conveyor (4) and angularly distributed about said axis (X) so as to be arranged in sequence along said closed transport path (P), each operating module (5) comprising a respective filling member (6), a respective sealing device (7) and a respective gripping head (8).

16. A method for filling and sealing containers (100) made of heat-sealable material, operated by means of a unit (1 ) according to any one of the preceding claims, comprising:- feeding the conveyor (4) with a container (100) which is open at the top, by means of said feeding station (2);- gripping said container (100) by means of the gripping head (8);- introducing a pre-portioned amount of material into said container (100) supported by the gripping head (8);- radially moving the container (100) by means of the gripping head (8) to bring the container (100) from the first closed trajectory (T1 ) to the second closed trajectory (T2);- engaging and sealing, by means of the sealing device (7), upper flaps (110) of the filled container (100), creating an ultrasonic seal of said upper flaps (110);- releasing the filled and sealed container (100) from the gripping head (8) towards said releasing station (3).

17. A method according to claim 16 when it depends on claim 2, wherein said engaging and sealing the upper flaps (110) of the filled container (100) by means of the sealing device (7) comprises performing a movement of the anvil (7b) along said at least partially radial trajectory between the opening configuration and the closing configuration.

18. A method according to claim 17, wherein the sonotrode (7a) is kept stationary with respect to the conveyor (4), preferably the methodcomprising adjusting the radial positioning of the sonotrode (7a) with respect to said axis (X) of the conveyor (4).

19. A method according to claim 17 or 18, wherein said radially moving the container (100) by means of the gripping head (8) to bring the container(100) from the first closed trajectory (T1) to the second closed trajectory (T2) is performed while the anvil (7b) is in the opening configuration.

20. A method according to any one of preceding claims 16 to 19, wherein the container (100) is made by means of two or more layers of film or laminated material, at least at an area of the container (100) subjected to said ultrasonic sealing.

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