EP2850005B1

EP2850005B1 - Device and method for the realisation of ventilated stabilizing coverings, made of plastic film, for palletized loads

Info

Publication number: EP2850005B1
Application number: EP13720573.8A
Authority: EP
Inventors: Emilio Murarotto
Original assignee: Bema SRL
Current assignee: Bema SRL
Priority date: 2012-05-16
Filing date: 2013-03-11
Publication date: 2016-10-19
Anticipated expiration: 2033-03-11
Also published as: WO2013171594A1; EP2850005A1; ITVR20120095A1

Description

TECHNICAL FIELD OF THE INVENTION

The present invention refers to a device and to a method for the realisation of stabilizing covering of the ventilated type obtained with plastic film for palletised loads.

STATE OF THE ART

Equipments are known for making stabilizing covering of the ventilated type, which are obtained with plastic film, for palletised loads. It is known that, after being wound around a palletised load according to conventional methods, plastic films are perforated through an equipment comprising a plurality of perforating punches that are associated with a mobile support structure, so as to make a plurality of vent holes in the covering.
One example of such equipment is described in Italian patent, n. 1361741 , and in the corresponding European document EP1721830B1 , in the name of the same Applicant.
Such equipment, that is a perforating station of an industrial packaging line, comprises a conveyor device, which is suitable for moving palletised loads that are covered with plastic film along a forward direction, and a perforating machine located on the side of the conveyor device itself.
The perforating machine is selectively suitable for moving closer to and away from the palletised load. The perforating machine comprises a series of perforating punches that are arranged along vertical lines so as to form a perforating matrix. Each of the perforating punches comprises a heatable head that locally softens the stabilizing covering so that, due to mechanical action, the perforating punch can then perforate the stabilizing covering.
The perforating punches are fixed to a support wall, which is fixedly connected to the support structure, through mechanical fixing means, for example clamp devices. Such punches are suitable for making vent holes on the plastic film at the empty spaces between one product and the next.
For example, in the case of bottles, in addition to the spaces between one bottle and the next, the vent holes could also be made at the necks of the bottles themselves, as long as the punches do not go too deep, but current perforating machines do not allow this precision.
The position of the empty spaces, at which the vent holes are made, can vary from one palletised load to another due to the different dimensions of the covered products.
Therefore, it is necessary to modify, each time, the position of the vent holes to be obtained by modifying the position of the perforating punches along the support wall. In this sense, it is necessary to act manually on the means for fixing the perforating punches, upon stopping the machine, the downtime of which can vary as a function of the modifications to be carried out.
Moreover, the new positioning of the perforating punches must be verified before proceeding on to the perforation of the covering of the palletised load so as to avoid damaging the products themselves.
There is thus a desire to be able to vary the position of the perforating punches with respect to the palletised load in a rapid and effective manner, reducing the machine downtime required to adapt, each time, the position of the perforating punches in relation to the size and arrangement of the palletised products.
Moreover, the device for perforating stabilizing coverings of palletised loads should be easy to integrate with an existing line for covering palletised loads, thus increasing its production flexibility with low costs.

PURPOSES OF THE INVENTION

One purpose of the present invention is to improve the state of the art.
A further purpose of the present invention is to propose a device for making vent holes in stabilizing coverings of palletised loads with plastic film, which makes it possible to modify the perforating arrangement in a rapid and effective manner thus reducing machine downtime.
Another purpose of the present invention is to propose a device for making vent holes in stabilising covering of palletised loads with plastic film that can be easily integrated with an existing line for covering palletised loads.
In accordance with one aspect of the present invention a device is foreseen according to claim 1.
The present invention, moreover, relates to a method for making vent holes in stabilizing coverings of palletised loads with plastic film according to claim 14.
The dependent claims refer to preferred and advantageous embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Further characteristics and advantages of the present invention shall become clearer from the detailed description of a preferred, but not exclusive embodiment, of a device for making vent holes in stabilizing covering of palletised loads with plastic film, illustrated as a non limiting indication, in the attached drawing tables, in which:

figure 1 is a perspective view of a device for perforating stabilizing coverings of palletised loads with plastic film according to the present invention;
figure 2 is a side view of the perforating device according to the present invention, coming closer to the palletised load;
figure 3 is a side view of the perforating device according to the present invention in a closer position to the palletised load;
figure 4 is a perspective view from the top of an enlarged detail of the perforating device according to the present invention;
figure 5 is a front view of the detail according to figure 4;
figure 6 is a side view of the perforating device according to the present invention in the perforating position;
figure 7 is a perspective view from below of a detail of the perforating device according to the present invention; and
figure 8 is a perspective view of other details of the perforating device acording to the present invention.

EMBODIMENTS OF THE INVENTION

With reference to the attached figures, reference numeral 1 wholly indicates a device for making vent holes in a stabilizing covering 31 made from plastic film, of a palletised load 32 (figures 2, 3 and 6). The palletised load 32 substantially projects according to a vertical direction "Z", a transversal direction "Y" and a longitudinal direction "X", the three directions being perpendicular to one another in space like the three Cartesian axes.
The device 1 comprises a mobile support structure 2, which is selectively suitable for moving closer to and away from a palletised load 32.
A perforating head 3 is slidably engaged with the support structure 2, said perforating head comprising perforating means 4, which are suitable for making holes in the stabilizing covering 31.
The support structure 2 comprises a fixed basement 5, guiding means 6 on which a mobile structure 7 is slidably engaged and movement means 8, which are selectively suitable for moving the mobile structure 7 towards the palletised load 32 or away from it.
For example, according to what is illustrated in greater detail in figures 7 and 8, the movement means of the mobile structure 7 can comprise a pneumatic cylinder 8; alternatively, such movement means 8 can be made with other equivalent means that are capable of exerting a constant force even for a relatively long time, obtained through an electric gearmotor that is associated with a pinion that engages onto a rack, not shown in the figure, which is fixedly connected to the basement 5 or similar devices that are suitable for the purpose.
In the embodiment shown in the figures, the mobile structure 7 has one part that extends according to the vertical direction "Z" and comprises a column 9 that is substantially vertical along which the perforating head 3 is slidably engaged.
The column 9 can be further fixedly connected to the mobile structure 7 through rods 10, which reduce possible oscillations of the column 9 itself during the operation of the device 1, and in general, make the mobile structure 7 itself stronger.
The vertical structure 9 thus made makes it possible to minimise the overall bulk of the support structure 2, and consequently of the device 1 itself, allowing there to be a better integration and installation thereof in pre-existing lines for wrapping and in general for covering palletised loads with plastic film.
The device 1, can indeed be easily installed along a covering line of palletised loads, by simply positioning the fixed basement 5 near to the area in which the ventilation hole is desired to be made on the covering of the palletised loads, without requiring further connections to means for supplying the palletised loads or in general to the line for moving the covered palletised loads.
The device 1 can moreover comprise a rotating table (not illustrated), which makes it possible to rotate the load 32 so as to make the vent holes on more than one side of the plastic film of the load 32.
The mobile structure 7 comprises an abutment bar 11, which substantially extends in a direction "Y" that is transversal with respect to the mobile structure 7.
The abutment bar 11 is suitable for resting against the base of the palletised load 32 (figure 3) due to the movement of the mobile structure 7 towards the load 32 itself and substantially according to the longitudinal direction "X".
Such resting at the base of the load 32 occurs through the action of the movement means, which in the case in the example in figures 7 and 8 are obtained through the pneumatic cylinder 8. Thanks to the possibility of adjusting the actuation pressure of the pneumatic cylinder 8, the resting action at the base of the load 32 occurs in a soft manner and can be kept constant over relatively long periods of time.
The resting of the abutment bar at the base of the load 32 makes it possible to control the actual position of the load itself and subsequently makes it possible to be able to realise the vent holes in the plastic film of the load 32 with high precision.
As shown in the embodiment of figure 1, the abutment bar 11 is fixedly connected to the column 9 through a pair of tubular elements 12, for example with a square-shaped, rectangular, or the like, section which project perpendicularly from the column 9.
The column 9 comprises a linear guide 13 to which the perforating head 3 is slidably associated according to the vertical direction "Z".
For the vertical displacement of the perforating head 3, vertical actuation means 33 are foreseen, illustrated more in detail in figure 7.
Such vertical actuation means 33 can be of the controlled type, i.e. the vertical position of the perforating head 3 is controlled and verified by sensor means. The sensor means for controlling and verifying the vertical position of the perforating head 3 can also be integrated in the vertical actuation means.
As an example, the vertical actuation means can comprise translation devices with drive belts, chains, or recirculating ball screws, or again translation devices with rack and pinion.
In the embodiment illustrated in figure 7, the vertical actuation means 33 comprise a gearmotor 34 that transmits its movement, through a chain drive 35, to a vertical translation mechanism 36 and an encoder (not illustrated) for controlling the vertical position of the perforating head 3.
The vertical translation mechanism 36 in turn comprises a drive belt 37, which is connected to the perforating head 3, a relative toothed wheel 38 for actuating the belt 37 and a transmission wheel (not illustrated) placed at the top of the column 9.
The perforating head 3 comprises a vertical sliding slide 40, which can slide on the column 9, and is fixed to the slide 40 through fixing means 41, which are equipped with shock-absorbing means 42-44, so as to allow small oscillations of the head 3 in the case of possible impact with the load 32.
Indeed, the fixing means 41 comprise four attachment points, two upper points 42 and two lower points 43 (figure 6), with springs 44 which allow small movements of the attachment points and consequently also of the perforating head.
The perforating head 3 moreover comprises a horizontal frame 14 which faces towards the stabilising covering, to which the perforating means 4 are operatively associated.
The horizontal frame 14 is thus substantially parallel to the abutment bar 11 and is substantially arranged according to the transversal direction "Y".
The horizontal frame 14 is essentially "C"-shaped, in plan, as shown in figures 1 and 4, comprising two ends 15.
Such ends 15 are connected to one another through a horizontal bar 16 for supporting the perforating means 4.
Each perforating means 4 comprises a support 17 for a perforating punch 18 and means 22 for connecting the support to the horizontal bar 16.
Each support 17 is operatively associated with the horizontal bar 16 through connection means 22.
The connection means 22 are suitable for selectively modifying the position of each perforating means 4 along the horizontal bar 16 as shall be indicated in greater detail in the rest of the description.
In the embodiment shown in the figures, a perforating head 3 is shown comprising six perforating means 4, which are arranged according to a line that is substantially parallel to the transversal direction "Y".
However, it is possible for there to be further embodiments of the perforating head 3 comprising a greater or lower number of perforating means 4, respective supports 17 and perforating punches 18, according to production requirements, without for this reason departing from the scope of protection of the present invention.
Each support 17 comprises a slide 20, to which the perforating punch 18 is fixedly connected, and means 21 for moving the slide 20.
The movement means 21, for example, are made through a pneumatic cylinder or the like, that is suitable for moving the slide 20 in the direction of the palletised load 32, so as to bring the perforating punch 18 closer to or away from the covering of the palletised load 32 and substantially according to the longitudinal direction "X".
The position of each support 17 along the horizontal bar 16 can be modified, in the transversal direction "Y", by acting on the connection means 22.
This variation of the position can occur in a manual manner by loosening the connection means 22 and by displacing the perforating means 4 in the desired position and by locking the connection means 22 again. According to another version of the present invention, the variation of the position can be achieved in an automatic manner through a transversal actuator (not illustrated) associated with each perforating means 4 that varies the position and therefore also the transversal position of the perforating means 4 from one another.
Through the connection means 22 it is thus possible to move the supports 17 closer or away in an independent manner from one another, and in a way such as to rapidly modify in an automatic and precise manner, the arrangement of the hole to be carried out in the covering of plastic film, along the transversal direction "Y".
Each perforating punch 18 is operatively associated with a heatable head 23.
The heatable head 23 is suitable for softening the stabilising covering of the palletised load with which it comes into contact, so as to make a hole.
The temperature of the heatable head 23 can be controlled and adjusted electronically. In such a way there is a reduction in the consumption of electricity necessary for heating it and consequently the costs for operating the device 1 are optimised.
Each support 17 comprises a fork 24, at the end of the heatable head 23, which faces onto the palletised load. As illustrated in the embodiment of figure 1, 4 and 5, the fork 24 has a slot 25 for the passage of the heatable head 23 and so as to allow a vertical adjustment of the heatable head 23 itself.
As illustrated more in detail in figure 6, the fork 24 allows a correct positioning of the heatable head 23 with respect to the stabilising covering of the palletised load.
Indeed, the fork 24 acts as an abutment for the heatable head 23, preventing it from advancing too far inside the stabilising covering 31, thus preventing the palletised products from being damaged.
In the case in which the load 32 is made up of bottles it is thus possible to form holes also at the necks of the bottles themselves (figure 6).
Moreover, each fork 24, during the step of moving the perforating means 4 away from the plastic film cover, promotes the detachment of the heatable head 23 from the stabilising covering itself. In such a way, indeed, it is possible to prevent the stabilising covering in plastic film from sticking to the individual heatable heads 23 and thus be subject to a traction that could compromise its integrity, when the perforating means 4 are moved away from the palletised load.
The perforating head 3 can moreover comprise a mobile bulkhead 26 for protecting the perforating means 4.
The mobile bulkhead 26 is fixedly connected rotatable with respect to the horizontal frame 14 through a pair of hinges 27. Each hinge 27 is positioned at one end of the mobile bulkhead 26.
The hinges 27 determine a rotation of the mobile bulkhead 26 around a horizontal axis 28, which is parallel to the horizontal frame 14.
The mobile bulkhead 26 can be rotated from a lowered position, in which it covers the perforating means 4, and a lifted position in which it leaves the perforating means 4 uncovered, and vice versa.
In the lowered position, the mobile bulkhead 26 is suitable for protecting the perforating means 4 and especially for protecting possible workers in the vicinity of the device 1, preventing them from being hurt by coming into contact with the heatable heads 23. The mobile bulkhead 26 can moreover be completely closed and insulated so as to reduce heat dispersion of the perforating means 4.
The mobile bulkhead 26 can comprise, near to the hinges 27, a rod 28 that is associated with automatic actuating means 29.
Such automatic actuation means 29 are suitable for rotating the mobile bulkhead 26 from the lifted position to the lowered position and vice versa.
The automatic actuation means 29, for example, can comprise a pneumatic or hydraulic actuator piston or a similar element that is suitable for the purpose.
In one version, given as a non limiting example of the automatic actuation means 29, when the piston comes out it determines the rotation of the mobile bulkhead 26 around the horizontal axis 28, causing it to lower. Vice versa, the return of the piston determines the lifting of the mobile bulkhead 26.
The device 1 also comprises a control unit 30 for the automatic management of the movement of the mobile structure 7 along the guide 6, of the vertical displacement of the perforating head 3 along the column 9, of the arrangement of the perforating means 4 along the horizontal frame 14, and of the movement of the perforating means 4 towards the palletised load or away from the palletised load, according to the longitudinal direction "X".
In particular, the control unit is suitable for managing the automatic operation of the device 1, and in particular:

the movement according to the longitudinal direction "X" of the mobile structure 7 with respect to the basement 5, towards and away from the palletised load 32;
the displacement according to the vertical direction "Z" of the perforating head 3 along the column 9;
the arrangement of each perforating means 4 along the horizontal frame 14, according to the transversal direction "Y";
the movement of each perforating means 4 in the direction towards and away from the palletised load 32, again according to the longitudinal direction "X";
the movement of the protection bulkhead 26 from the lifted position to the lowered position and vice versa.

The operation of the present invention is as follows. A palletised load 32, after being covered with a plastic film, is positioned near to the device 1, for example through a supply line that is not shown in the figure.
The mobile structure 7, which is initially in a position away from the palletised load, is displaced along the guide 6 of the fixed basement 5, resting at the base of the palletised load 32, for example against the wooden pallet on which the products are rested, and according to the longitudinal direction "X".
The perforating head 3 is displaced along the column 9, according to the vertical direction "Z", and is positioned at a certain height with respect to the base of the palletised load.
Subsequently, the perforating head 3 is displaced to the different heights defined by the type of products that form the load 32.
Therefore, the perforating means 4 are made to advance towards the palletised load, bringing the heatable heads 23 and the respective forks 24 in contact with the stabilising covering made from plastic film, again according to the longitudinal direction "X".
The heatable heads 23, determine an initial softening of the stabilising covering made from plastic film and after the forward movement of the perforating punches 18 towards the palletised load, achieve the perforation through mechanical action.
Therefore, the perforating means 4 are moved, according to the longitudinal direction "X", away from the palletised load 32.
In sequence the vent holes are made at different heights of the stabilising covering by varying the position of the perforating head 3 according to the vertical direction "Z" along the column 9.
Once the vent holes have been made in the stabilising covering made from plastic film, the mobile structure 7 is moved, according to the longitudinal direction "X", away from the palletised load 32 so as to allow it to move away towards further work stations or towards a store, etcetera.
The device 1 makes it possible to vary, in an automatic and rapid manner, the arrangement of the holes made in a stabilising covering of palletised loads with plastic film.
The height of the perforating head 3 can be changed in a rapid and automatic manner and, therefore, it makes it possible to achieve a correct perforation at the different layers of palletised products without requiring the machine to be stopped so as to modify the position of the single perforating punches 18. Moreover, the spacing of the single perforating means 4 along the horizontal bar 16 can be changed manually in a very simple manner.
According to another version of the present invention, the positioning of the perforating means 4 along the horizontal bar 16 can be controlled in an automatic manner during the operation of the device 1 itself, further increasing the number of the holes that can be made through the device 1 without requiring the machine to be stopped.
The invention thus conceived can undergo numerous modifications and variants all covered by the scope of the inventive concept as defined in the claims.
Moreover, all the details can be replaced by other technically equivalent elements. In practice, the materials used, as well as the contingent shapes and sizes, may be any according to the requirements without for this reason departing from the scope of protection of the following claims. In the case in which the technical characteristics mentioned in the claims are followed by reference numerals, such reference numerals are introduced with the sole purpose of making the claims clearer and consequently the aforementioned reference numerals do not have a limiting effect on the interpretation of each element identified as an example by such reference numerals.

Claims

Device (1) for making aerating holes in a stabilizing covering (31) made of plastic film, for a palletized load (32), said load (32) developing substantially along a vertical direction ("Z"), a transversal direction ("Y") and a longitudinal direction ("X"), said directions being perpendicular to each other, said device (1) comprising a support structure (2) provided with a fixed basement (5), and with a vertical structure (7, 9) extending substantially along the vertical direction ("Z"), a perforating head (3) arranged on said vertical structure (7, 9) and provided with perforating means (4) for making aerating holes in said covering, characterised in that said perforating means (4) extend along a line and substantially along the transversal direction ("Y") and in that said vertical structure (7, 9) comprises vertical actuating means (33) adapted to move said perforating head (3) along said vertical direction ("Z") along the vertical structure (7, 9).
Device (1) according to claim 1, wherein said vertical actuating means (33) comprise toothed belt translating devices (36-38), or chain translating devices, or recirculating balls screws, or rack-and-pinion translating devices.
Device (1) according to claim 1 or 2, comprising sensor means for controlling and verifying the vertical position of said perforating head (3), said vertical actuating means (33) thus being of controlled type.
Device (1) according to the previous claim, wherein said sensor means for controlling and checking the vertical positioning of the perforating head (3) are integrated in the vertical actuating means (33).
Device (1) according to one of the previous claims, wherein said fixed basement (5) comprises translating means (8) suitable to move the vertical structure (7, 9) closer to, and away from, said palletized load (32) substantially along the longitudinal direction ("X").
Device (1) according to one of the previous claims, wherein said perforating head (3) comprises a horizontal frame (14) that is essentially "C"-shaped in plan and comprises two ends (15) and a horizontal bar (16) connecting said ends (15), said horizontal bar (16) supporting said perforating means (4), wherein each of said perforating means (4) comprises a support (17) for a perforating punch (18) and means (22) for connecting said support (17) to said horizontal bar (16), selectively movable along said horizontal bar (16) and substantially along the transversal direction ("Y").
Device (1) according to claim 6, wherein said perforating punch (18) comprises a heatable head (23) adapted to soften said stabilizing covering (31) of said palletized load (32) for making aerating holes.
Device (1) according to claim 6, wherein said support (17) comprises a slide (20), to which said perforating punch (18) is constrained.
Device (1) according to the previous claim, wherein said support (17) comprises means (21) for moving said slide (20) closer to, or away from, said palletized load (32) and substantially along the longitudinal direction ("X").
Device (1) according to claim 7, wherein said support (17) comprises, at the end of said heatable head (23), facing said palletized load (32), a fork (24) adapted to be placed in abutment against said stabilizing covering of said palletized load (32).
Device (1) according to the previous claim, wherein said fork (24) has a slot (25) for allowing said heatable head (23) to pass therethrough and so as to allow an adjustment of the vertical relative position between heatable head (23) and fork (24).
Device (1) according to claim 6, wherein said perforating head (3) comprises a movable bulkhead (26) for protecting said perforating means (4), said movable bulkhead (26) being pivotably constrained, through a pair of hinges (27), around a horizontal axis parallel to said horizontal frame (14).
Device (1) according to claim 6, wherein said device (1) comprises a control unit (30) for the automated management of the movement of said vertical structure (7) along said guide (6), of said perforating head (3) along said vertical structure (7) and of said perforating means (4) along the horizontal frame (14) and closer to/away from the palletized load and substantially along the respective directions ("Z") and ("X").
Method for making aerating holes in a stabilizing covering (31) of a palletized load (32), such load developing along a vertical direction ("Z"), a transversal direction ("Y") and a longitudinal direction ("X"), said directions being perpendicular to each other, said method comprising a perforating step for making a plurality of holes in said stabilizing covering (31) of said palletized load (32), through thermal perforating means (4), arranged according to a perforating line substantially parallel to the transversal direction ("Y"), characterised in that it comprises repeating said perforating step of said stabilizing covering (31) of said palletized load (32) along a perforating line substantially parallel to a transversal direction ("Y") by translating said perforating line substantially along a vertical direction ("Z") along said palletized load (32).
Method according to claim 14, wherein said step of vertical translation comprises translating a perforation head (3), wherein said perforating means (4) are provided, in a controlled manner, i.e. the vertical translation is controlled and checked by sensor means for controlling and checking the vertical positioning.
Method according to claim 14 or 15, comprising a step of resting an abutment bar (11) associated to said perforating means (4) to a base of said palletized load (32) so as to check the actual position of said palletized load (32).
Method according to any one of the claims 14-16, wherein said step of perforating said stabilizing covering (31) comprises a step of resting said perforating means (4) on said stabilizing covering (31) through a fork (24) provided in said perforating means (4), so as to check the actual position of the stabilizing covering (31).
Method according to any one of the previous claims from 14 to 17, comprising changing the relative position of said perforating means (4), according to the vertical direction ("Z"), with respect to a plurality of holes previously realised in said stabilizing covering (31) according to the perforating line substantially parallel to the transversal direction ("Y").