DEVICE AND METHOD FOR ASSISTING IN THE FILLING AND CLOSING OPERATION OF A PACKAGE AND STATION FOR FILLING AND CLOSING A PACKAGE IN A PACKAGING MACHINE WHICH COMPRISES SAID DEVICE

Abstract

Method for filling and closing a package including the operations of introducing two arms through the mouth, each one having or bearing a gripping tool and impressing a mutual distancing movement on the arms to expand the package with a retention mechanism which operates outside the package to grasp the walls of the package arranged between the arms and the retention mechanism while the retention mechanism approaches and fits over the gripping tool of each arm, such that when the arms move in the direction of the mouth of the package, the arms carry the grasped walls of the package to produce folds towards the interior of the package. For flexible tubular net packages, the at least one gripping tool on each arm has the shape of a protuberance and that the method includes passing through a wall of the package with the gripping tool

Claims

1. A device for assisting in the filling and closing operation of a package, including flexible tubular net packages, which comprises two drive units arranged opposite and adapted for receiving an empty package there between, characterized in that each unit comprises at least one movable arm and an actuator group capable of moving the arm in a first direction of movement from an initial position which does not interfere with the receipt of the package to a position in which the distal ends of the arms are introduced by way of the mouth of the package and push the walls of the same outwards to expand it with the first objective of facilitating the filling operation, each arm having or bearing on said distal end at least one gripping tool suitable for passing through a hole of the net and each arm being equipped with retention means capable of being moved between a release position distanced from the gripping tool and a captive position in which they fit over said gripping tool, being able to capture or grasp the portion of the net passed through by the tool, the actuator group being capable of moving the arm in a second direction of movement inverse to the first, the retention means adopting the captive position thereof, a movement which allows the captured portions of net to be pulled towards the interior part of the package with the second objective of forming respective lateral folds intended to facilitate the correct closure of the package.

2. The device according to claim 1, characterized in that the at least one gripping tool is configured in the manner of a protuberance capable of passing through a hole of the net.

3. The device according to claim 2, characterized in that the protuberance has a rod or sharp pin shape.

4. The device according to claim 1, characterized in that the retention means comprise a piece mounted adjacent to the arm and longitudinally displaceable with respect to the arm according to a linear movement between the release position, distanced from the gripping tool of the arm and the captive position in which the piece fits on said gripping tool to capture or grasp a portion of the net and vice versa.

5. The device according to claim 4, characterized in that the piece has a retention end, intended to cooperate with the tool for retaining a net portion, equipped with an indentation or depression in which the tool of the associated arm is at least partially introduced when the piece adopts the captive position.

6. The device according to claim 1, characterized in that the retention means are actuated by means of an actuator, preferably electric or pneumatic, inseparable from the associated arm.

7. The device according to claim 1, characterized in that the arm or arms of each drive unit are mounted on a rotary axis around an axis of rotation such that the arm or arms of the same unit are capable of swiveling around said axes of rotation simultaneously in the first and in the second directions of movement of each operative cycle of the device, and in that the axes of rotation of both units are parallel.

8. The device according to claim 7, characterized in that the rotary axes are displaceably supported, but in a guided manner, on each drive unit by mechanical support on a guide or surface of a cam, the rotation of axis being precisely that which causes the displacement thereof on the guide or over the cam, all of which in a manner which can impress a composite movement on the associated arms, specifically rotating around an axis which is displaced.

9. The device according to claim 7, characterized in that each drive unit comprises two arms coupled to the respective rotary axis with the capacity to displace along a section of the cited rotary axis, both arms being capable of being displaced simultaneously in opposing directions, approaching and moving away from each other, in each operative cycle of the device.

10. The device according to claim 9, characterized in that the two arms of the same drive unit are connected to each other by means of an element with elastic properties which acts under compression such that, departing from an initial position in which the arms of the same unit are separated a predetermined distance, if these are actively pulled in opposite directions, approaching each other, the element with elastic properties is compressed and once said pulling force ceases to be exerted on the arms, both arms are automatically separated as the element with elastic properties tends to recover the original shape thereof.

11. A method for filling and closing a package, especially for flexible tubular net packages which maintaining the package held suspended by the upper open mouth thereof, comprises the operations of a) introducing through the mouth thereof at least two arms each one bearing at least one gripping tool and impressing on them a distancing movement to expand the package; b) depositing products in the interior of the package by way of the mouth thereof; c) using retention means which operate outside of the package, grasping the walls of the package arranged between the arms and the cited retention means when said retention means approach and fit over the gripping tool of each arm; d) moving the arms in the direction of the mouth of the package, bringing with them the grasped walls of the package to produce folds towards the interior of the package; e) closing the package, flattening the upper mouth thereof and pleating the folds produced in order to prevent the latter from becoming undone.

12. The method according to claim 11, characterized in that the at least one gripping tool has the form of a protuberance and in that the method comprises passing through a wall of the package, where appropriate, a hole of the net, with said gripping tool.

13. The method according to claim 11, characterized in that it comprises the operation of releasing the walls of the package grasped in the operation c) separating the retention means from the gripping tool of each arm prior to proceeding with the operation of removing the arms from the package.

14. A station for filling and closing a package in a packaging machine, especially for flexible net packages, which comprises a device according to claim 1; and a pair of holding clamps configured for holding an empty package suspended, said clamps being capable of approaching or moving away from each in order to cooperate in a synchronized manner with the movable arms of both units of the device in the operations of filling the package and subsequently closing the upper edge thereof, the station also comprising transfer means with two pressing plates arranged one at each side of the package actuatable in order to approach each other and adopt a transfer position, in which they grasp the package, flattening it transversally joining opposing walls of the same, preventing the lateral folds formed in the cited package from becoming undone and in order to be displaced together and thus transport the grasped package to a contiguous station of the machine, said pressing plates being placed and dimensioned such that in the transfer position they interfere with the path of the arms from the initial position thereof until the position in which, introduced in the package, they push the walls of the same to expand it.

15. The station for filling and closing according to claim 14, characterized in that it is equipped with a tube for pouring products with an outlet hole and in that it is provided with foldable deflectors suited for directing the products poured through the outlet of the tube towards the mouth of the package, each deflector being formed by a wing of flexible material which is rigidized with a rigid material core which extends in a direction parallel to that of the arms of each drive unit of the device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0043] FIGS. 1a to 1f schematically show a sequence of the operations which are carried out when feeder means are used which operate from the exterior of the package to produce folds at both sides of the package during the filling and closing thereof which is representative of the state of the art;

[0044] FIGS. 2a to 2d schematically show a sequence of the operations which are carried out following the method according to one variant of the invention;

[0045] FIG. 3 is a schematic plan view of the device according to one embodiment of the invention in which each drive unit is provided with two arms, showing the initial position for receiving an empty package;

[0046] FIG. 4 is a schematic view analogous to FIG. 3 showing a fictitious position in which the arms have acted to form the folds in the package, and in which the holding clamps of the mouth of the package have been approximated with respect to each other so as not to interfere with the provisional closing of said package;

[0047] FIGS. 5a to 9a and FIGS. 5b to 9b are respectively perspective views and profile views of a drive unit provided with two arms, showing different positions of the arms and of the retention means with respect to the gripping tool;

[0048] FIGS. 10 and 11 respectively show schematic and perspective views of two different embodiments of the retention means, which act on the gripping tool;

[0049] FIGS. 12a and 12b respectively show two end positions of a cam inseparable in movement with the rotary axis of an arm, capable of transmitting to said rotary axis a guided displacement of the same according to one embodiment of the invention;

[0050] FIG. 13 is a perspective schematic view of a filling and closing station according to one embodiment of the invention; and

[0051] FIG. 14 is a perspective view of a tube for pouring products provided with foldable deflectors.

DETAILED DESCRIPTION OF THE INVENTION

[0052] The sequences of FIGS. 1a to 1f and 2a to 2d show different methods to be followed in order to implement folds in a package 2 held suspended by the upper mouth thereof in a filling and closing station for packages in a packaging machine.

[0053] The sequence of FIGS. 1a to 1f show a method known in the state of the art which uses feeders in the form of rotary blades 4′ which act from outside the package 2.

[0054] In each working cycle of the station, the rotary blades 4′ adopt an essentially horizontally starting position, shown in FIG. 1a which does not interfere with the horizontal path for introducing the package into the station.

[0055] The station should be equipped with means 4a′ suitable for cooperating in the expansion of the package 2 during the filling operation, the rotary blades 4′ remaining at a distance from the package 2, as FIG. 1b shows.

[0056] The folds can then be implemented in the package 2, using the rotary blades 4′. In order to carry out the function thereof, said rotary blades 4′ should rotate freely around the axes thereof an angle notably greater than 90° until adopting an operative position in which the ends thereof push the walls of the package 2 inwards, whereby it is necessary for said blades 4′ to have the ends thereof below the vertical projection of the mouth of the package 2, all of which as FIGS. 1c and 1d show.

[0057] The package 2 can then be provisionally closed by approximating the walls of the same on the upper mouth thereof and the package 2 can be held by transfer means, schematically illustrated in the sequence, which use plates 7′ which act one at each side of the package 2, approaching each other in order to flatten it, pleating the lateral folds previously formed and holding it under pressure between plates 7′. However, note that the rotary blades 4′ should carry out a return movement, rotating around the axes thereof in a direction contrary to that of the folding direction, which cannot interfere with the transfer means 7′ as FIG. 1e illustrates. Additionally, the means 4a′ which cooperate to maintain the package 2 expanded should be withdrawn so as not to interfere with the closing of the package 2.

[0058] This free return movement of the rotary blades 4′ is again notably greater than 90° until reaching the original starting position so as not to interfere with the transfer path of the filled package 2 to a subsequent station in the machine or with the path of a new package 2 to be filled which will be introduced into the filling station.

[0059] The sequence of FIGS. 2a to 2d shows an alternative method for proceeding according to a variant of the present invention, which uses movable arms 4 which act from within the package 2.

[0060] In each working cycle of the station, these arms 4 adopt an essentially horizontal starting position, shown in FIG. 2a, which does not interfere with the horizontal path for introducing the package 2 into the station.

[0061] These arms 4 are moved in order to introduce the ends thereof into the package 2 by way of the mouth thereof and to push the walls of the same outwards with the first objective of cooperating with the expansion of the package 2 during the filling operation, as FIG. 2b shows.

[0062] In order to carry out this first objective, the arms 4, in the movement thereof, should rotate an angle of approximately 90° until adopting a first operative position illustrated in said FIG. 2b.

[0063] The folds in the package 2 can then be implemented, using the same arms 4 which have cooperated in the expansion of the package 2. For such purpose, the arms 4 bear a gripping tool 5 and retention means 6 are used which operate outside of the package 2 and which grasp the walls of the package 2 arranged between the arms 4, which remain introduced in the package 2, and the cited retention means 6 while said retention means 6 approach and fit over the gripping tool 5 of each arm 4, then the arms 4 being moved towards the interior of the package 2 and towards the mouth of the same, bringing with them the grasped walls of the package 2 in order to produce both folds towards the interior of the package 2, as FIG. 2c illustrates. In order to implement this second objective, that of folding, the arms 4 should rotate at least 90° with respect to the position which they adopt during the expansion and filling of the package 2.

[0064] In the illustrated variant, suited for net packages, the arms 4 bear, on the distal ends thereof at least one gripping tool 5 in the form of a protuberance capable of passing through a hole of the net and the retention means 6 are mounted on the arms 4 and consequently are moved together with the arms 4, being capable of being moved also with respect to the arms 4 between a release position distanced from the gripping tool 5 and a captive position in which they fit over said gripping tool 5, being able to capture or grasp the portion of the net passed through by the tool 5, all of which as is described in detail below.

[0065] Subsequent to the formation of the folds, the package 2 can be provisionally closed approximating the walls of the same on the upper mouth thereof and the package 2 can be held by the transfer means, schematically illustrated in the sequence, which use plates 7 which act one at each side of the package 2, approaching each other to flatten it, pleating the lateral folds before previously formed and holding it under pressure between the plates 7. However, note that the arms 4 should now not carry out a return movement or be moved in a direction contrary to that which causes the folds in the package 2, but the arms 4 continue moving in a direction to the mouth of the package 2, prior to the release from the walls of the same until adopting the initial position again as FIG. 2d illustrates.

[0066] The mentioned release of the walls of the package 2 is achieved by arranging the retention means 6 in the release position thereof, distanced from the gripping tool 5, which is the position which they originally adopt and which FIGS. 2a and 2d illustrate.

[0067] It should be noted that as the arms 4 follow a movement with an ascending path, the mechanical interferences with the plates 7 of the transfer means are avoided, said plates can be arranged at a level closer to the mouth of the package 2 and can have greater dimensions, which contributes to an improved hold and to maintaining the folds in the desired shape during the transfer of the package 2.

[0068] Note that there is practically no free movement of the arms 4, since these perform a first objective when they are moved in order to arrange the ends thereof in the interior of the package 2, which is to expand the package 2; and a second objective when they are moved in reverse which is to produce the folds in the package 2. This means that they utilize all the displacements of the arms 4 and that independent auxiliary means are not required to expand the package 2 as is the case with the method of FIGS. 1a to 1f.

[0069] Similarly, the angle of rotation of the arms 4 is much smaller than that which the rotary blades 4′ require from the example of FIGS. 1a to 1f, which economizes the execution times of the operations carried out.

[0070] As is detailed below, the invention also envisaged that the arms 4 can carry out a composite movement, not strictly rotating around a fixed axis of rotation. For such purpose, it is envisaged that the arms 4 rotate around both axes, but that these are displaceably mounted in a guided manner on the structure or chassis of the device or of the station. This allows the same device 1 to be more versatile specifically that the same set of arms 4 can be adapted to different sizes of packages 2.

[0071] The method according to FIGS. 2a to 2d is also compatible with other needs, which can arise in a folding operation such as the need to have to carry out more than one fold at each side of a package 2. Thus, as is also described below, it is envisaged that the device 1 used comprises two drive units 3 each one with two arms 4 mounted on a common rotary axis 8, but with the capacity to approach or move away from each other, in order to not obstruct the provisional closing operation of the packages 2.

[0072] The arms 4 can each bear one or more gripping tools 5 and the shape of the retention means 6, especially of the part, which should fit over the gripping tool or the gripping tools 5, can also vary.

[0073] The gripping tool 5 or, where appropriate, the gripping tools, if there is more than one, can be formed on the arm 4 or can be formed by pieces originally separated and subsequently joined to the same, preferably in a firm manner, for example, by welding, but other forms of joining are also considered such that they allow the gripping tool or tools to be replaced. In the case of the gripping tool 5 being formed on the arm, it is, for example considered that the arm has at the distal end thereof a portion folded or bent at an angle, conveniently mechanized in order to give it the optimal shape and it is this bent portion which carries out the function of the gripping tool.

[0074] Below a preferred exemplary embodiment of the device 1 of the invention is described which comprises two drive units 3 arranged opposed and adapted for receiving with respect to each other an empty package 2, each unit 3 being provided with two arms 4, as can be observed, for example in FIG. 3.

[0075] In said FIG. 3, a view is depicted from above of both drive units 3 with the arms 4 arranged in an essentially horizontal starting position, which corresponds to the profile view shown in FIG. 2a, the position thereof not interfering with the horizontal reception path of an empty package 2 (not shown). Furthermore, a pair of holding clamps 12 belonging to the filling and closing station 100 is shown (see FIG. 13) configured such that they can hold an empty package 2 suspended, said clamps 12 being capable of approaching and moving away from each other in order to cooperate in a synchronized manner with the movable arms 4 of both units 3, as is described below.

[0076] The two arms 4 of each unit 3 are mounted on a rotary axis 8 around an axis of rotation 8a such that the arms 4 of the same unit 3 are capable of swiveling around said axes of rotation 8a simultaneously in first and second opposite directions of movement in each operative cycle of the device 1. Furthermore, the rotary axes 8 of both units 3 are parallel and are actuated by both actuator groups 4a (see FIGS. 12a, 12b and 13), for example of the type which each comprise an electric motor.

[0077] In addition, the two arms 4 of each unit 3 are coupled to the respective rotary axis 8 with the capacity to displace along a section of the cited rotary axis 8, both arms 4 being capable of being displaced simultaneously in opposing directions, approaching and moving away from each other in each operative cycle of the device by the action of said holding clamps 12.

[0078] FIG. 4 shows a fictitious position similar to FIG. 2c in which the formation of the folds in the package 2 created between the pairs of arms 4 of each unit 3 can be observed, and in which the holding clamps 12 are actuated approximating each other and in turn pulling the respective arms 4 of each unit 3 in order to allow the provisional closing of the package 2.

[0079] Additionally, the arms 4 of the same unit 3 are connected by means of an element 11 with elastic properties, such as a helical spring which works under compression such that once the clamps 12 cease exerting the pulling force on the arms 4, both arms 4 of each unit 3 are automatically separated when said element 11 with elastic properties tends to recover the original shape thereof, allowing the return of the pairs of arms 4 to the initial position thereof (see FIG. 3).

[0080] In the case of this embodiment with two arms 4 on each drive unit 3, the method for the filling and closing of a package is thus similar to that described in FIGS. 2a to 2d, as is shown below in FIGS. 5a to 9b.

[0081] In FIGS. 5a and 5b, a drive unit 3 can be observed provided with two arms 4 in the initial position, analogous to FIG. 2a, in which the arms 4 adopt an essentially horizontal position, which does not interfere with the horizontal reception path of an empty package 2.

[0082] In FIGS. 6a and 6b, the position is shown in which said arms 4 have rotated an angle of approximately 90° until adopting a position analogous to that of FIG. 2b such that the ends thereof have been introduced into the package 2 by way of the mouth thereof and push the walls of the same outwards with the first objective of cooperating with the expansion of the package 2 during the filling operation.

[0083] As has been mentioned, each arm 4 bears at the distal end thereof at least one gripping tool 5 suitable for passing through a hole of the net of the package 2. In this example, two tools 5 are depicted with the shape of a sharp protuberance.

[0084] Furthermore, each arm 4 is equipped with retention means 6 capable of being moved between a release position distanced from the gripping tools 5 shown in FIGS. 6a and 6b and a captive position shown in FIGS. 7a and 7b in which they fit over said gripping tools 5 to capture or grasp the portion of the net passed through by the tools 5.

[0085] In FIGS. 8a and 8b, a position is shown, similar to that of FIG. 2c in which the arms 4 with the retention means 6 arranged in the captive position have started to rotate in the inverse direction to the first with the aim of pulling the captured portions of net towards the interior part of the package to implement the formation of the lateral folds.

[0086] Furthermore, it is observed that the arms 4 are together due to the pulling action of the holding clamps 12 (see FIG. 4) to proceed to the provisional closure of the package 2.

[0087] As has been mentioned, the package 2 can be held by transfer means, for example in the manner of plates 7 (see FIG. 2c and FIG. 13) which act one at each side of the package 2 approaching each other to flatten it, pleating the lateral folds previously formed and holding it under pressure between the plates 7.

[0088] Lastly, once the package has been partially closed and held by means of said plates 7 of the transfer means, the retention means are deactivated to release the captured portions of the package 2, as can be seen in FIGS. 9a and 9b.

[0089] The arms 4 are actuated to return towards the initial position (see FIGS. 5a and 5b) in which they adopt a substantially horizontal position and they are again separated while said holding clamps 12 are in turn moved away with the aim of receiving a new empty package 2.

[0090] In the embodiment described, the retention means 6 are configured by a piece mounted adjacent to the arm 4 and longitudinally displaceable with respect to said arm 4 according to a linear movement between the release position and the captive position and vice versa.

[0091] In order to actuate said retention means 6, in this example a transmission 6c of the rack and pinion type is used, said displaceable piece of the retention means 6 being provided with a rack which is capable of being moved by means of the actuation of a pinion mounted in the structure of the arm 4 and the pinion being actuated by means of an actuator such as an electric motor.

[0092] In FIGS. 10 and 11, two embodiments of said retention means 6 can be observed. According to a first embodiment, said retention means 6 comprise a retention end equipped with a through indentation 6a in the form of a fork (see FIG. 10), while according to a second embodiment the retention end is equipped with a blind indentation 6b (see FIG. 11), both indentations 6a, 6b being configured for suitably catching the tool or tools 5 of the arm 4 during the captive position. It should be emphasized that in these two embodiments, a single gripping tool 5 is depicted for reasons of clarity.

[0093] According to a preferred embodiment, the arms 4 can carry out a composite movement, not strictly rotary around the rotary axis 8, as is explained below.

[0094] According to a preferred embodiment, in order to carry out said composite movement of the arms 4, a cam 10 is used mounted inseparable in movement with the rotary axis 8 of the arms 4 of each unit 3, as can be observed in FIGS. 12a and 12b. Said cam 10 is equipped with a sliding rail 9 displaceable on a pivot 10a fixed to the chassis of the device 1 or station 100 such that when the rotary axis 8 of the arms 4 rotates, it causes the displacement of the cam 10 by way of the guide 9 thereof, which in turn produces a translation movement of the rotary axis 8 with respect to the fixed pivot 9.

[0095] In FIG. 12a, the initial position is depicted, corresponding to FIGS. 5a and 5b in which the arms 4 (partially depicted) adopt an essentially horizontal position which does not interfere with the horizontal reception path of an empty package 2.

[0096] In FIG. 12b, the position can be observed, corresponding to FIGS. 6a and 6b, in which the arms 4 have rotated an angle approximately 90° towards the interior of the package 2 by way of the mouth thereof to expand the walls of the same outwards. In this case, the movement of the cam 10 by way of the guide 9 thereof causes the rotary axis 8 to be displaced outwards with respect to the package, separating the respective arms 4 of both units 3 from each other, which contributes to improving the expansion of the walls of the package 2 during the filling of the same.

[0097] In addition, the cam configuration 10 allows the adaptation of the same device 1 to different sizes of packages 2.

[0098] In FIG. 13, a station 100 for filling and closing a package 2 in a packaging machine can be observed in a simplified manner, in which some components have been removed for greater clarity. In this case, the two drive units 3 opposing each other can be observed with the two pairs of arms 4 arranged in a position corresponding to FIGS. 9a and 9b.

[0099] As has been mentioned, the station 100 comprises two holding clamps 12 capable of approaching or moving away from each other in order to cooperate in a synchronized manner with the movable arms 4 of both units 3 of the device 1 in the filling operations of the package 2 and subsequent closure of the upper edge thereof, and also comprises transfer means provided with two pressing plates 7 arranged one at each side of the package 2 actuatable in order to approach each other and adopt a transfer position, in which they grasp the package 2, flattening it transversally joining opposing walls of the same, preventing the lateral folds formed in the cited package 2 becoming undone and to be displaced together and thus transport the grasped package 2 to one contiguous station of the machine.

[0100] The station 100 also comprises a tube 13 for pouring products, shown in FIG. 14, which comprises an outlet hole and which is provided with foldable deflectors 14, suited for directing the products poured through the outlet of the tube 13 towards the mouth of the package 2, each deflector 14 being formed by a wing 14a of flexible material which is rigidized with a rigid material core 14b which extends in a direction parallel to that of the arms 4 of each drive unit 3 of the device 1.