Patent Application
20180072443
The present invention relates to a packaging apparatus comprising an evacuation assembly and to a packaging process. The packaging process includes moving a packaged product through an evacuating station where gas or air inside the package is evacuated prior to sealing of the package.
A packaging apparatus may be used to package a food product. The product may be a product by itself or a product pre-loaded onto a tray. A tube of plastic wrap is continuously fed through a bag/package forming, filling and sealing apparatus. The film and the product are joined or otherwise brought together or placed with respect to one another. For example, the product is deposited on the film or the film is wrapped around the product. In some examples, the product is fed through an infeed belt. A tube is created around the product by sealing opposite longitudinal edges of the film. Alternatively, the product is placed in the tube and a leading edge of the packaging is sealed. Then the tube is sealed at the trailing edge (at the upstream end) of the package and is separated (e.g. cut) from the continuously moving tube of packaging.
The tube may be provided as a tube, or be formed from two films or webs sealed longitudinally at two longitudinal edges, or from a single film that is folded over and sealed along its longitudinal edges.
Sealing bars may be used to seal the package, wherein a lower bar and an upper bar are moved, at least one with respect to the other or both with respect to one another, in order to contact each other, squeezing the packaging material therebetween and providing one or more seals. The sealing bars typically also form an adjacent seal, which comprises the opposite end of a following package, and a cut between the two seals, thereby providing one semi-sealed package (e.g. having an open end, typically the end of the tube fed into the packaging apparatus) and a separate (e.g. cut off) sealed package during a single packaging process step.
The seals are typically transversally extending regions of packaging material that have been processed to provide a seal between the inside of the packaging and the environment. Gas or air may be trapped in the package in the space between the product and the film after sealing both ends. A common problem in a packaging process is to achieve a desired reduction of the amount of gas or air in a package prior to sealing the package.
It is sometimes desirable to evacuate the package so as to reduce the package volume. Additionally, evacuation of the gas from the package may improve packaging appearance after heat shrinking and may also reduce the possibility of deterioration of the product due to exposure to oxygen or other gas(es). For example, some food products (e.g. cheese) may oxidize or develop mold over a period of time if an unsuitable atmosphere (e.g. containing oxygen) is contained within the package. A suitable atmosphere may essentially consist of or comprise one or more protective gases, and/or inert gases, or essentially consist of or comprise a modified atmosphere. Modified atmosphere packaging (MAP) typically comprises reducing the amount of oxygen (O2) inside a package, for example, from approximately 21% to about 10%, preferably to about 5%, more preferably to about 0%. This can substantially reduce or prevent growth of aerobic organisms and/or oxidation reactions. Oxygen thus removed may be replaced with an inert gas, for example nitrogen (N2), or with a gas that can lower the pH or inhibit the growth of bacteria, for example carbon dioxide (CO2). It is noted that any gas or mixture of gases commonly known in packaging can be used. Carbon monoxide can be used for preserving the red color of meat.
One way of evacuating a package is to puncture or perforate the package with small holes before or after the goods are sealed therein. The small holes allow the excess gas within the package to be expelled, for example by mechanical application of force or simply by the force of gravity settling the products during shipment, or, preferably, by heat shrinking the packaging material. However, this particular solution to the problem has disadvantages, for example when foods are contained within the package. The pinholes allow the ingress of contaminants or environmental air from outside the package, for example containing oxygen. The pinholes may be covered during or after packaging in suitable ways, for example, by applying stickers.
Another way of deflating packages is to evacuate the inside of the package or container through the fill opening using a vacuum process. A vacuum (or volume of significantly lower pressure than ambient pressure) is generated and applied in order to extract excess gas or air from inside the package. In this manner, the packaging material (e.g. film) is collapsed prior to sealing the opening. However, the use of a vacuum system may increase the complexity of the packaging apparatus and/or have negative effects on the time required for the packaging process, due to the time required for applying the vacuum to the package through its opening.
Further, vacuum systems often require the installation of equipment within the fill tube to close the tube off from the environment. Such additional equipment may reduce the tube diameter, which may cause plugging due to product bridging. Further, the additional equipment renders the apparatus and its operation more complex and expensive. Alternatively, the process may require packages to be evacuated to be brought into a vacuum chamber, necessitating also additional equipment and/or further processing steps with similar effects on cost and complexity.
A further way of deflating packages is to provide mechanical force directly to the outside of the package before the sealing takes place. Examples of this are sponge rubber or coiled springs which engage the outside of the package to expel excess gas prior to the time the sealing jaws engage and seal the fill opening.
However, the surfaces of a product within the package are often irregular and, thus, tend to cause uneven wear of the foam rubber and uneven elongation of the springs. As a result of the uneven wear and deterioration from the close proximity to the heated sealing elements, the long term manufacturing standards may not be maintained at a desired level. Additionally, fragile products are easily crushed by exterior mechanical applications of force. Additional drawbacks of using mechanical force via sponge rubber may include poor hygiene due to difficulties of cleaning porous material such as sponges, thereby providing ideal media for bacterial growth. Further, the sponge or coils may push the film into contact with the product thereby changing the appearance of the product. For example, in the case of meat, blood may soil the interior of the film.
Further, variations of the product size may cause problems for mechanical deflators. When using mechanical deflators, correction of these variations requires a shutdown of the machine to modify the deflation force or position. This is because it is necessary to provide different pressure pads individually shaped for the packages and products to be processed.
U.S. Pat. No. 4,964,259 discloses a process and apparatus for forming, filling, sealing and deflating a package of goods prior to the time the fill opening is sealed. The system includes a blast of air against the exterior flexible sidewalls of the package thereby to bring the sidewalls of the package closer together before sealing, thereby to reduce the amount of trapped gas sealed in the package.
JP 2003-072702 discloses a bag-packing machine having a chamber. By the pressure of compressed air supplied into the chamber through an air hose, a bag is pressed to push out the air in the bag through the back edge, which is open.
DE 10 2009 017 993 discloses a packaging apparatus comprising a perforation unit which is configured to perforate the lower film in order to facilitate evaporation of gas, for example ethylene or CO2, when packaging products that generate such gas during ripening. Also, such products may require a constant oxygen content while being packaged.
DE 10 2007 013 698 discloses a packaging apparatus comprising a means for providing a controlled atmosphere inside a package depending on a breathing property of the package product.
WO 2008/122680 discloses a packaging machine based on applying mechanical force to a film arranged around a product to be packaged by means of a tamper device and further on shrink-wrapping the film around the product by means of an oven device. Excess air or gas is expelled both by means of the tamper device and by means of shrink-wrapping.
U.S. Pat. No. 5,590,509 discloses a process for packaging a product on a receptacle. The process includes blowing air heated to a temperature suitable for heat-shrinking the film onto an outer surface of the forward sealed end region of a tubing to pre-shrink the tubing and to expel gas. The process further includes stopping the heat shrinking before the film contacts the product by supplying a cold flow of air.
An aim of the present invention is to provide an evacuation assembly for a packaging process in which excess gas or air is expelled from a package before sealing. Another aim of the present invention is to provide a packaging apparatus comprising the evacuation assembly. Another aim of the present invention is to provide an evacuation assembly that facilitates efficient evacuation of packages of different sizes.
According to the invention, in a 1st aspect there is provided a packaging apparatus comprising a control unit, a loading station configured to position a tubular film around a product to be packaged, a sealing station coupled to the control unit, the control unit being configured to control the sealing station to create one or more seals on the tubular film, an evacuation assembly coupled to the control unit, the evacuation assembly including a first member and a second member arranged opposite the first member, the first member including a deformable portion, the first and second members being relatively movable between a first configuration, in which the first and second members are spaced apart from one another, a second configuration, in which the deformable portion contacts at least part of the second member and/or part of the tubular film which in use is resting against the second member, and a third configuration in which the deformable portion is compressed in a compression direction towards the second member; and a means for moving the product relative to and from the evacuation assembly.
In a 2nd aspect according to the 1st aspect, the deformable portion delimits a chamber having an opening towards the second member.
In a 3rd aspect according to the 2nd aspect, when the first and second members are in the second or third configuration, the chamber is closed against the second member and defines a working portion on the second member, the perimeter of which is configured to encompass a product positioned in a package and placed in correspondence of the working portion.
In a 4th aspect according to aspect 2 or 3, the first member comprises a holder portion, the deformable portion being coupled to the holder portion and facing the second member.
In a 5th aspect according to the 4th aspect the deformable portion extends along a perimeter of the holder portion.
In a 6th aspect according to any one of aspects 2 to 5, when the first and second members are in the second configuration, the holder portion and the second member are positioned at a first distance from one another, providing the chamber with a first volume; and when the first and second members are in the third configuration, the holder portion and the second member are positioned at a second distance, smaller than the first distance, from one another, providing the chamber with a second volume smaller than the first volume.
In a 7th aspect according to the 6th aspect, the first distance ranges from 100 mm to 500 mm, preferably from 160 mm to 300 mm; and/or the second distance ranges from 50 mm to 250 mm, preferably from 80 mm to 150 mm; and/or the second volume ranges from 6 liters to 30 liters.
In an 8th aspect according to any one of aspects 1 to 7, the deformable portion comprises a deformable region, the deformable region having a bellows-type structure extending circumferentially along the second portion, optionally the deformable region comprising one or more of rubber, fabric, cardboard, composite material including rubber and fabric and/or cardboard, deformable plastic, LLDPE, PLA, PA, and LLDPE, PLA, PA including an additive, the additive optionally being rubber.
In a 9th aspect according to any one of aspects 1 to 8, the deformable portion comprises an outer portion and an inner portion, optionally the outer and/or inner portions having the form of a layer of film material.
In a 10th aspect according to the 9th aspect, the inner portion is at least partially permeable to air or gas and comprises a compliant material, optionally the compliant material being selected from foam material, closed or semi-closed cell foamed PU, and Silicon foam.
In an 11th aspect according to any one of aspects 9 or 10, the outer layer is substantially impermeable to air or gas and comprises a compliant material, in particular select from single or multilayer film material, optionally comprising LDPE, PA, PVC, and/or Silicon.
In a 12th aspect according to any one of aspects 9 to 11, the inner portion consist entirely of an alveolar, optionally foam material, preferably closed or semi-closed cell foamed PU or Silicon foam, and the outer portion consist entirely of a plastic film impermeable to air or gas.
In a 13th aspect according to any one of aspects 9 to 12, the outer portion comprises one or more flow regulators, the one or more flow regulators being configured to allow the passage of air or gas, optionally the one or more flow regulators being configured to allow the passage of air or gas when a pressure differential between opposite sides of the outer portion reaches or exceeds a pre-determined maximum value, optionally the maximum value ranging from 1 kPa to 50 kPa (0.01 bar to 0.50 bar), preferably from 5 kPa to 20 kPa (0.05 bar to 0.20 bar), more preferably from 10 kPa to 15 kPa (0.10 bar to 0.15 bar).
In a 14th aspect according to any one of aspects 1 to 13, the compression direction is substantially perpendicular to a working surface of the second member facing the first member.
In a 15th aspect according to any one of aspects 1 to 14, the packaging apparatus further comprises an output station, the control unit being coupled to the output station and configured to control an output of one or more sealed packages from the packaging apparatus; and/or a flusher, the control unit being coupled to the flusher and configured to control the flusher to provide the inside of the tubular film and/or the inside of a semi-sealed package with one of an inert gas, a mixture of inert gases, or a modified atmosphere; and/or a shrink station, the control unit being coupled to the shrink station and configured to control the shrink station to heat-shrink one or more sealed packages.
In a 16th aspect according to any one of aspects 1 to 15, the head consists of a first part and a second part, at least one of the first and second parts being relatively movable with respect to the other, optionally along an adjustment direction extending substantially parallel to a motion direction of products along the packaging machine.
In a 17th aspect according to the 16th aspect, the first part and the second part are configured to slidably engage one another, thereby allowing the relative movement to adjust a size of the head.
In a 18th aspect according to any one of aspects 16 or 17 and aspect 3, the relative movement of the first part and the second part determines the size of the working portion.
In a 19th aspect according to any one of aspects 1 to 18, the packaging apparatus further comprises an actuator coupled to the control unit and configured to relatively move the first and/or second members into the first, second, and third configurations.
In a 20th aspect according to the 19th aspect, the actuator is configured to relatively move the first and/or second members into the first, second, and third configurations in accordance with a pre-determined respective profile defining one or more of the following parameters: a rate of relative movement over time from 0.5 m/s to 2.0 m/s, preferably from 0.7 m/s to 1.5 m/s more preferably from 1.0 m/s to 1.2 m/s; a minimum and/or maximum retention time from 0.05 s to 1.0 s, more preferably from 0.1 s and 0.7 s, even more preferably from 0.1 s to 0.3 s, for any one of the first, second, and third configurations; and an actuation force applied to the first and/or second members when relatively moving the first and/or second members into the second or third configuration, the actuation force ranging from 5 N to 400 N, preferably from 20 N to 200 N.
In a 21st aspect according to any one of aspects 1 to 20, the means for moving are configured to move products along a motion direction along the packaging machine, optionally the means for moving being configured to move products along the motion direction substantially continuously and/or without stopping.
In a 22nd aspect according to the 21st aspect, the first and second members are configured for accommodating, when in the second and third configurations, a translatory motion corresponding to the motion direction.
In a 23rd aspect according to any one of aspects 21 or 22, the sealing station is configured for accommodating a translatory motion corresponding to the motion direction.
In a 24th aspect, there is provided a packaging process comprising providing a semi-sealed package containing a product to be packaged, the semi-sealed package being made from a tubular film and having a first sealed end and a second open end; providing an evacuation assembly including a first member and a second member arranged opposite the first member, the first member comprising a deformable portion, wherein the first and second members are relatively movable between: a first configuration, in which the first and second members are spaced apart from one another, a second configuration, in which the deformable portion contacts at least part of the second member and/or part of the tubular film which in use is resting against the second member, and a third configuration in which the deformable portion is compressed in a compression direction towards the second member, wherein the deformable portion defines, when in the second or third configuration, a working portion on the second member, the perimeter of which is configured to encompass the product positioned in the semi-sealed package and placed in correspondence of the working portion; relatively moving the first and/or second members into the first configuration; relatively positioning the semi-sealed package and the evacuation assembly such that the first sealed end and the product are positioned within the working portion and the second open end extends beyond the working portion, relatively moving the first and/or second members into the second configuration where the deformable portion contacts the film at an intermediate portion of the second open end resting against the second member, and relatively moving the first and/or second members into the third configuration by compressing the deformable portion and determining a gas flow from inside the semi-sealed package out of the second open end; and sealing the semi-sealed package at the second open end, thereby forming a sealed package containing the product and having first and second sealed ends.
In a 25th aspect according to the 24th aspect, the deformable portion delimits a chamber having an opening towards the second member, and optionally wherein relatively moving the first and/or second members into the first configuration comprises opening the chamber or keeping it open.
In a 26th aspect according to any one of aspects 24 to 25, relatively moving the first and/or second members into the second or third configuration comprises closing the chamber or keeping it closed against the second member and defining the working portion on the second member, the perimeter of which being configured to encompass the product positioned in the semi-sealed package and placed in correspondence of the working portion.
In a 27th aspect according to any one of aspects 24 to 26, the first member comprises a holder portion, the deformable portion being coupled to the holder portion and facing the second member.
In a 28th aspect according to the 27th aspect, the deformable portion extends along a perimeter of the holder portion.
In a 29th aspect according to any one of aspects 25 to 28, relatively moving the first and/or second members into the second configuration comprises relatively positioning the holder portion and the second member at a first distance from one another, thereby providing the chamber with a first volume; and wherein relatively moving the first and/or second members into the third configuration comprises relatively positioning the holder portion and the second member at a second distance, smaller than the first distance, from one another, thereby providing the chamber with a second volume smaller than the first volume.
In a 30th aspect according to the 29th aspect, the first distance ranges from 100 mm to 500 mm, preferably from 160 mm to 300 mm; and/or the second distance ranges from 50 mm to 250 mm, preferably from 80 mm to 150 mm; and/or the second volume ranges from 6 liters to 30 liters.
In a 31st aspect according to any one of aspects 24 to 30, the deformable portion comprises a deformable region, the deformable region having a bellows-type structure extending circumferentially along the second portion, optionally the deformable region comprising one or more of rubber, fabric, cardboard, composite material including rubber and fabric and/or cardboard, deformable or rigid plastic, LLDPE, PLA, PA, Teflon; and LLDPE, PLA, PA including an additive, the additive optionally being rubber.
In a 32nd aspect according to any one of aspects 24 to 30, the deformable portion comprises an outer portion and an inner portion, optionally the outer and/or inner portions having the form of a layer of film material.
In a 33rd aspect according to the 32nd aspect, the inner portion is at least partially permeable to air or gas and comprises a compliant material, optionally the compliant material being selected from foam material, closed or semi-closed cell foamed PU, and Silicon foam.
In a 34th aspect according to any one of aspects 32 to 33, the outer layer is substantially impermeable to air or gas and comprises a compliant material, in particular select from single or multilayer film material, optionally comprising LDPE, PA, PVC, and/or Silicon.
In a 35th aspect according to any one of aspects 32 to 34, the inner portion consist entirely of an alveolar, optionally foam material, preferably closed or semi-closed cell foamed PU or Silicon foam, and the outer portion consist entirely of a plastic film impermeable to air or gas.
In a 36th aspect according to any one of aspects 32 to 35, the outer portion comprises one or more flow regulators, the one or more flow regulators being configured to allow the passage of air or gas, optionally the one or more flow regulators being configured to allow the passage of air or gas when a pressure differential between opposite sides of the outer portion reaches or exceeds a pre-determined maximum value, optionally the maximum value ranging from 1 kPa to 50 kPa (0.01 bar to 0.50 bar), preferably from 5 kPa to 20 kPa (0.05 bar to 0.20 bar), more preferably from 10 kPa to 15 kPa (0.10 bar to 0.15 bar).
In a 37th aspect according to any one of aspects 24 to 36, the compression direction is substantially perpendicular to a working surface of the second member facing the first member.
In a 38th aspect according to any one of aspects 24 to 30, the packaging process further comprises providing a flusher and controlling the flusher to provide the inside of the tubular film and/or the inside of the semi-sealed package with one of an inert gas, a mixture of inert gases, or a modified atmosphere; and/or providing a shrink station controlling the shrink station to heat-shrink the sealed package.
In a 39th aspect according to any one of aspects 29 to 38, determining the gas flow from inside the semi-sealed package out of the second open end comprises creating an increase in pressure within the chamber corresponding to a ratio between the first and second volumes.
In a 40th aspect according to any one of aspects 24 to 39, relatively moving the first and/or second members into the first, second, and third configurations is performed in accordance with a pre-determined respective profile defining one or more of the following parameters: a rate of relative movement over time from 0.5 m/s to 2.0 m/s, preferably from 0.7 m/s to 1.5 m/s more preferably from 1.0 m/s to 1.2 m/s; a minimum and/or maximum retention time from 0.05 s to 1.0 s, more preferably from 0.1 s and 0.7 s, even more preferably from 0.1 s to 0.3 s, for any one of the first, second, and third configurations; and an actuation force applied to the first and/or second members when relatively moving the first and/or second members into the second or third configuration, the actuation force ranging from 5 N to 400 N, preferably from 20 N to 200 N.
In a 41st aspect according to any one of aspects 24 to 40, the first member consists of a first part and a second part, and the packaging process further comprises relatively moving at least one of the first and second parts with respect to the other, optionally along an adjustment direction extending substantially parallel to a motion direction of products along the packaging machine.
In a 42nd aspect according to the 41st aspect, the first part and the second part are configured to slidably engage one another, and the packaging process further comprises relatively moving at least one of the first and second parts with respect to the other to adjust a size of the first member.
In a 43rd aspect according to any one of aspects 41 or 42, the packaging process further comprises relatively moving at least one of the first part and the second part in order to determine the size of the working portion.
In a 44th aspect according to any one of aspects 24 to 43, the packaging process further comprises controlling an actuator to relatively move the first and/or second members into the first, second, and third configurations.
Advantages of the packaging apparatus comprising the evacuation assembly, and the packaging process include overcoming the limitations described above. In particular, the apparatus and process facilitate simple and efficient evacuation of packages because complex components, for example vacuum pumps, can be eliminated from the packaging apparatus. Further advantages include a more robust, reliable, and durable packaging process and apparatus, as the evacuation does not necessitate contact between, for example, a sponge or spring component with the package and/or product. This also reduces wear and tear. Moreover, in cases where identical products are packaged, it is not necessary to provide a sponge/spring component exactly shaped to fit the product. And in cases where non-identical products are packaged (e.g. natural products like poultry, vegetables, fruit, etc.), providing a sponge/spring element exactly shaped to fit the product is not feasible due to variations in the product. Further advantages include more flexibility with respect to product sizes and/or tube diameters. The components can be easily adapted, adjusted, or exchanged and tube diameter, typically limited due to requirements imposed by a vacuum system, is not restricted in the same manner. Further advantages are described in more detail below.
The products 20 to be packaged may assume different states (20a, 20b, 20c) of being packaged. States 20a, 20b, 20c denote product 20 being in different packaging states. For example, state 20a denotes product 20 positioned inside tubular film 21. State 20b denotes product 20 positioned in a semi-sealed package 22, wherein the semi-sealed package 22 has a first end, downstream in terms of a motion direction 30′ of products 20 along packaging machine 1, which is sealed, and a second (upstream) end, which is open. State 20c denotes product 20 positioned in a sealed package 23 having first and second sealed ends (i.e. wherein both the upstream and the downstream end of the package are sealed).
In state 20a, a film 21 is positioned around product 20 or product 20 is positioned in a tubular film 21. Alternatively, in state 20a product 20 is positioned on film 21, which is subsequently folded over and sealed at its longitudinal edges in order to form a tubular film 21. This may be carried out at the loading station.
The sealing station 3 comprises an upper sealing and cutting member 31 and a lower sealing and cutting member 32 configured to seal and cut the packaging, i.e. the material of film 21. Sealing and cutting members 31 and 32 are configured to create a first seal on film 21, thereby creating the semi-sealed package 22 containing product 20 in state 20b and having a first sealed end at the downstream end of semi-sealed package 22. Product 20 in state 20b is situated inside film 21 and semi-sealed package 22 comprises a sealed end and an open end.
Sealing and cutting members 31 and 32 are further configured to create a second seal on film 21, thereby creating a sealed package 23. In state 20c, product 20 is situated inside film 21 and sealed package 23 comprises a first sealed end and a second sealed end at both the upstream and downstream ends thereof.
Sealing and cutting members 31 and 32 may be configured to create both seals at once. For example, sealing and cutting members 31 and 32 may create the second seal of a first product 20 and the first seal of a second product 20, located upstream with respect to the first product 20 and a moving direction of products 20 along packaging apparatus 1, at substantially the same time, so that subsequently the first product 20 is contained in a sealed package 23 and the second product 20 is contained in a semi-sealed package 22.
For sealing and/or cutting, the sealing and cutting members 31 and 32 are brought from a first configuration, in which the members 31 and 32 are spaced apart from one another, into a second configuration, in which the members 31 and 32 are substantially in contact with one another.
In order to facilitate sealing and/or cutting film 21, sealing and cutting members 31 and 32 are arranged so that film 21 is interposed between members 31 and 32. Members 31 and 32 may have active or working surfaces that are configured to face film 21 and each other in a manner that film 21 is, in the second configuration of members 31 and 32, substantially in contact with both working surfaces. Further, where no film 21 is interposed between members 31 and 32, members 31 and 32 are substantially in contact with each other, wherein contact may be made by means of the active or working surfaces of both members 31 and 32.
Sealing and cutting members 31 and 32 may further be configured to form a transversal seal in the packaging. A transversal seal denotes a seal oriented substantially transversal to a longitudinal extension of film 21 and to the direction of movement of the products. In the case of the packaging being supplied from a roll of film 21, the sealing and cutting members 31 and 32 may form a transversal seal across the tube of film 21, substantially perpendicular to the length of film 21.
Generally, the means for moving 30 are configured to move products in a main moving direction 30′ along packaging apparatus 1. Means for moving 30 may comprise one or more conveyor belts know in the art, for example an infeed belt (see reference numeral 30 on the right hand side of
Evacuating station 6 includes evacuation assembly 60, which comprises a head 60a (e.g. a first member) and a support 60b (e.g. a second member) arranged opposite one another. Head 60a comprises a first portion 66 (below also denoted as “holder”) configured to carry a second portion 68 (below also denoted as “apron”), wherein the second portion 68 extends along a perimeter of the first portion 66, thereby defining a chamber 60c delimited by an inner wall 68c of the second portion 68. Chamber 60c has an opening 60d at the bottom thereof, towards support 60b.
Support 60b may consist of a separate component (e.g. a separate conveyor belt or other means for moving) or consist of a portion of means for moving 30, as shown in
In the embodiment shown, head 60a is carried by actuator 62 which provides head 60a with a vertical movement towards support 60b and away therefrom. In general, it is noted that either head 60a is movable with respect to support 60b (as shown in
Sealing station 3 and evacuation assembly 6 are further configured to support translatory motion along the main moving direction 30′ of products 20 along packaging apparatus 1. This means that both sealing station 3 and evacuation assembly 6, jointly or independently, can follow the main moving direction 30′ as long as sealing and/or evacuation takes place. In case of sealing station 3, sealing bars 31 and 32 can be configured to allow the translatory motion during the time it takes to create a seal on the tubular film 21. In detail, sealing bars 31 and 32 are brought into contact with one another, while the tubular film 21 containing the products 20 is continuously moving along the main moving direction 30′. While sealing bars 31 and 32 are in contact, sealing the film, both sealing bars 31 and 32 move together with the packages 22, 23 and the tubular film 21 along the main movement direction 30′. Upon creation of the seal, sealing bars 31 and 32 release contact and, thus, the tubular film 21, and return to their spaced-apart configuration, i.e. primarily vertically, but also longitudinally, thereby going back on the translatory movement performed while sealing.
Substantially the same applies to evacuation assembly 6, where head 60a is brought into contact with support 60b, which is a corresponding counter surface of means for moving 30. Head 60a can be configured to allow the translatory motion during the time it takes to evacuate a semi-sealed package 23. In detail, head 60a is brought into contact with support 60b, while the tubular film 21 containing the products 20 and resting against support 60b is continuously moving along the main moving direction 30′. Here, support 60b, being a portion of an upper surface of means for moving 30, continuously moves along the main movement direction 30′. While head 60a and support 60b are in contact, evacuating the package, both head 60a and support 60b move together with the packages 22, 23 and the tubular film 21 along the main movement direction 30′. Upon the package being evacuated, head 60a and support 60b release contact and, thus, the tubular film 21, and return to their spaced-apart configuration, i.e. primarily vertically, but also longitudinally, thereby going back on the translatory movement performed while the evacuation took place.
Apron 68 of head 60a may comprise a compliant material or structure (e.g. foam, bellows) such as to facilitate deformation of apron 68 upon establishing contact between apron 68 and support 60b. The side wall of chamber 60c may entirely be defined by the apron 68 and particularly by the inside surface of the apron. For example, the apron may entirely be made in a deformable material or deformable structure (e.g., foam or bellows as described herein below), or a part of the apron such at least 30% or from 30% to 50% of the vertical extension of the apron may be made in deformable material (e.g., foam or bellows as disclosed herein below). Within the scope of this document, establishing contact means at least part of one element directly contacting another element (e.g. making physical contact). Establishing contact, however, also includes other parts of the two elements being in very close proximity to each other, possibly separated only by one or more layers of a plastic film (e.g. film 21), so that the film may be interposed between the two elements (e.g. partly covering the contact surface or surfaces). With respect to the above, two opposing layers of tubular film 21 extending along packaging apparatus 1 and into evacuating station 6 may be interposed between apron 68 of head 60a and support 60b along part of the perimeter of apron 68, thereby providing a channel for fluid (e.g. gas, air) flow between and through the tubular film without compromising a substantially sealed contact between apron 68 and support 60b. Ensuring substantially sealed contact with support 60b along the perimeter of apron 68 may be achieved by apron 68 comprising a compliant material or structure.
Head 60a may further comprise one or more flow regulators 64 (e.g. opening, valve) providing for desired fluid flow (e.g. gas, air) between chamber 60c and the ambient atmosphere. In
Packaging apparatus 1 further comprises a control unit 50. The control unit is connected (individual connections are not shown in the figures for reasons of clarity) to one or more components of the packaging apparatus 1, for example the loading station, sealing station 3, sealing and cutting members 31 and 32, means for moving 30, evacuating station 6, shrink tunnel 33, and flusher 34. Hot air or shrink tunnel 33 may be provided in order to shrink film 21 of packages 23. Flusher 34 may be provided in order to flush the inside of the packaging film 21 with a protective gas or a protective mixture of gases. For reasons of clarity, the figures generally do not show individual connection lines between the control unit 50 and other components. It is noted that the packaging apparatus 1 may comprise common connection means for connecting control unit 50 to other components, for example electrical, optical, or other connections and/or leads.
Control unit 50 may be configured to control the transport of products 20 along a predefined path, e.g. by controlling one or more (e.g. electrical) motors comprised in means for moving 30 in a step-by-step motion or in a continuous motion. The control unit may also control individual actuators of different components as described below, for example, in order to create transverse seals on the tubular film at sealing station 3 by individually controlling actuators connected to sealing bars 31 and/or 32, as well as by controlling sealing bars 31 and/or 32 directly (e.g. heating units comprised therein).
Control unit 50 may comprise a digital processor (CPU) with memory (or memories), an analogical type circuit, or a combination of one or more digital processing units with one or more analogical processing circuits. In the present description and in the claims it is indicated that the control unit is “configured” or “programmed” to execute certain steps. This may be achieved in practice by any means, which allow for configuring or programming the control unit. For instance, in case of a control unit comprising one or more CPUs, one or more programs are stored in an appropriate memory. The program or programs contain instructions, which, when executed by the control unit, cause the control unit to execute the steps described and/or claimed in connection with the control unit. Alternatively, if the control unit is of an analogical type, then the circuitry of the control unit is designed to include circuitry configured, in use, to process electric signals such as to execute the control unit steps herein disclosed.
Control unit 50 may be connected to one or more components comprised in evacuating station 6 (e.g. actuator 62) and be configured to send and/or receive control signals to/from evacuating station 6. Control unit 50 may further be configured to control actuator 62 in order to move head 60a of evacuation assembly 60 relative to support 60b (or vice versa), such that chamber 60c may be opened, closed, and modified in its internal volume due to relative movement between head 60a and/or support 60b. In one example, as shown in
In some embodiments, including any one of the first, second, third, and fourth embodiments, portion 68 comprises at least two different materials. For example, portion 68 can comprise a more rigid material (e.g. cardboard, fabric) in an upper region thereof and a more compliant material (e.g. rubber, silicon) in a lower region thereof. In one example, an upper half of portion 68 comprises cardboard and a lower half comprises silicon. In another example, portion 68 comprises a more rigid material in an upper and a lower region thereof and a more compliant material in an intermediate region (i.e. between the upper and lower regions) thereof. Using a plurality of materials for portion 68 can entail the advantage that the overall stability and/or stiffness of portion 68 can be modified without compromising the ability of portion 68 to be compressible. To this aim, a distribution, arrangement, overlap, composite structure, and/or other combination of two or more materials may be selected accordingly.
Control unit 50 may be configured to control means for moving 30 and/or individual components thereof (e.g. an infeed belt, an exit belt). For example, control unit 50 may be configured to increase and decrease an operating speed of means for moving 30. Control unit 50 may further be configured to control the operating speed of means for moving 30 depending on a position of products 20 with respect different components of packaging apparatus 1. For example, control unit 50 may be configured to control an operating speed of means for moving 30 such that individual products 20 positioned in respective semi-sealed or sealed packages are positioned relative to evacuating station 6, such that semi-sealed package 22 is positioned directly in correspondence of opening 60d of chamber 60c of head 60a of evacuation assembly 60, and/or such that products 20 are positioned relative to members 31 and 32 of sealing station 3 in order to create respective seals on the adjacent package(s).
In particular, in another aspect, the control unit 50 may be configured to control one or more components depending on signals sent to and/or received from other components. For example, the control unit 50 may be configured to control an activation of one or more components depending on the position of products 20 and/or tubular film 21 with respect to other components of packaging apparatus 1. This way, the control unit 50 may activate, for example, the sealing and cutting members 31 and 32 when one product 20 is in state 20a and another product 20 is in state 20b (or state 20d), such that between the two products 20 the first and second seals are created on the film 21, respectively.
As described in more detail further below, evacuation of packages is achieved by compression of portion 68 between portion 66 of head 60a and support 60b. By means of the compression, the internal volume of chamber 60c is reduced, resulting in a corresponding increase in pressure within chamber 60c. Due to the fact, that the package within chamber 60c is a semi-sealed package 23 having an open end extending out from chamber 60c, the increased pressure facilitates expulsion of air from inside the package and through the open end thereof. One key factor in the evacuation, as described in detail with respect to
As soon as the air inside a semi-sealed package 22 has been expelled, sealing and cutting members 31 and 32 create the second seal at the open end of semi-sealed package 22, thereby creating sealed package 23 containing product 20. Sealing and cutting members 31 and 32 may, during the same operation, create the first sealed end for the packaging of the subsequent product 20, which is in state 20a, situated inside tubular film 21, upstream of now sealed package 23, thereby creating a semi-sealed package 22 for the subsequent product 20.
Means for moving 30 may comprise one or more conveyor belts 30. The one or more conveyor belts are configured to transport the products 20 in states 20a, 20b, and 20c, for example as packages 22 and 23, along a pre-defined path through the packaging apparatus 1. For example, the packaging apparatus may comprise at least two conveyor belts 30 as shown in
The one or more channels 68g are configured to prevent excess pressure upon support 60b and/or part of tubular film 21, which in use is resting against the second member 60b, such that upon compression of portion 68 air and/or gas can flow through the part of tubular film resting against the support 60b. The one or more channels 68g are configured to allow fluid communication between the inside of a semi-sealed package 23 and an ambient atmosphere through the open end of the semi-sealed package 23 (for clarity, the semi-sealed package 23 is not shown in
As shown, one or more channels 68g in accordance with the second variant can be provided as a continuous layer of compliant material (e.g. material more compliant than a material of portion 68; e.g. soft plastic foam material) arranged along a region of contact between portion 68 and support 60b and/or tubular film 21 resting against support 60b, thereby reducing a contact force exerted by portion 68 in this region of contact. In this example, the one or more channels 68g can be provided as a separate layer placed upon inner layer 68b (the latter being provided with a corresponding recess receiving the one or more channels 68g). An outer layer 68a can extend over the one or more channels 68g or being provided with a corresponding recess. It is noted that the outer layer 68a—if present—typically does not exert a substantial pressure upon support 60b and/or tubular film 21 resting against support 60b. It is further noted that the first and second variants are specifically disclosed also with respect to embodiments of head 60a having a portion 68 comprising a bellows structure 65 (see further below; e.g.
In some embodiments, including any one of the first, second, third, and fourth embodiments, the one or more channels 68g can be configured to perform a function corresponding to that of the flow regulators 64 and/or 64′ (see above). To this aim, the configuration (e.g. size, shape, number, etc.) and/or the material (e.g. more or less permeable plastic foam) of the one or more channels 68g can be selected in line with the desired air/gas flow between the inside and the outside of chamber 60c.
In a first step, as shown in the transition between
As the second open end of package 22 is held between head 60a and support 60b as well as between sealing and cutting bars 31 and 32 of sealing station 3, an inner volume 63b contained within semi-sealed package 22 is still in fluid communication with the ambient atmosphere by means of a channel defined between opposing layers of film along the second open end of package 22. An outer volume 63a, outside of semi-sealed package 22 and inside chamber 60c, is substantially sealed from the ambient atmosphere by head 60a substantially sealingly contacting support 60b as well as semi-sealed package 22.
In a second step, as shown in
Upon completion of air/gas expulsion, as shown in
With respect to the process steps described above, it is noted that the movements of head 60a and/or support 60b may be performed in accordance with a pre-determined respective profile defining one or more of the following parameters. The rate of relative movement over time can range from 0.5 m/s to 2.0 m/s. In some embodiments the rate of movement preferably ranges from 0.7 m/s to 1.5 m/s and more preferably from 1.0 m/s to 1.2 m/s. The retention time, which denotes head 60a and/or support 60b being held in a fixed configuration with respect to one another, may range from 0.05 s to 1.0 s, minimum and maximum retention time, respectively. In some embodiments the retention time preferably ranges from 0.1 s to 0.7 s, and more preferably from 0.1 s to 0.3 s. These minimum and maximum retention times are applicable to one or more of the spaced apart configuration (see
In other embodiments, the material of the downstream wall of apron 68 can be made from a more compliant material. This variant allows the downstream wall to accommodate a preceding packaged product without necessitating a recess 69. In such embodiments, the downstream wall of apron 68 can be made from an inner layer comprising a more compliant (e.g. softer, more flexible) material or it can comprise an inner layer 68b having a smaller thickness. It is noted that the variant also applies to the other embodiments shown, in particular to embodiments in which apron 68 has a bellows type structure. Also in these embodiments, the downstream wall can be modified with respect to the remaining walls of apron 68 in the same manner as described above.
On the right of
In a first step, as shown in the transition between
Upon completion of air/gas expulsion, as shown in
As shown in
In accordance with a fourth embodiment of the present invention, evacuation assembly 60 is provided with an adjustable head 60t comprising relatively movable parts 60t-1 and 60t-2. At least one of parts 60t-1 and 60t-2 is movable with respect to the other (or both with respect to one another) in an adjustment direction 61. As can be seen in
It is further noted that the fourth embodiment has been illustrated having a bellows-type apron 68t. However, the telescopic adjustment of head 60t can be combined with other types of aprons and can, for example, be provided with an apron substantially corresponding to that of the first embodiment (see, e.g.,
In a variant of the fourth embodiment, the telescopic adjustment of head 60t comprises adjusting merely the position of the downstream wall. In a manner substantially corresponding to what is described above with respect to
Packaging apparatus 1 may comprise an HFFS machine. The HFFS machine may comprise a conveyor belt 30 for supporting and transporting the packages 22, in a horizontal direction. Product 20 may be within a package. The package 22 is unsealed when the gas is expelled from the package. The packaging may comprise a film 21. For example, the product 20 may be wrapped or partially wrapped in a film 21. The film 21 extends around the product 20. Gas is enclosed with the product 20 by the film 21. Product 20 may be disposed on a surface. The surface may extend substantially in the horizontal direction. The surface may comprise the upper surface of a conveyor belt 30. The conveyor belt 30 may be a continuous conveyor belt 30. For example, the conveyor belt 30 may be suspended between at least two rollers. The conveyor belt 30 may transport the product 20 in a horizontal direction. Product 20 may be disposed in a tray. The tray supports the product 20. The tray may comprise walls that extend substantially vertically from the base of the tray to a height greater than the vertical dimension of the product 20. Alternatively, the tray height may be less than or equal to the height of the product 20. The packaging extends around the tray. The tray may comprise a material selected from a list consisting of polystyrene, Aluminium, or other thermoplastic material such as PET, or cardboard. The tray may be rigid, solid or foamed, and have any color and shape.
The packaging material may comprise a multi-layer film 21. Film 21 may comprise a polyolefin. The film 21 may be a fully coextruded shrinkable film 21. Package 23 provides a barrier to gas passing between the interior of the package 23 to the exterior of the package. Accordingly, the environment inside the package 23 is isolated from the environment outside the package. This helps to preserve food products 20 and avoid contamination. This may be advantageous with respect to food hygiene. Package 23 may provide a barrier to aromas or to gasses. This may be particularly useful when the product 20 is a food product 20. The package 23 may be abuse-resistant. The packaging material may be transparent or translucent. This may allows a customer to see the product 20 through the packaging. For example, the packaging may comprise a transparent film 21. The packaging film may be anti-fog. This ensures high consumer appeal. The packaging film may be printable. This allows labels to be printed directly onto the packaging. The packaging may be formed from a roll of film 21. Tubular film 21 may be created by forming a tube from the roll of film 21. Packaging apparatus 1 may comprise a former configured to form the roll of film 21 into a tube. The former may form the tube by forming a longitudinal seal along the longitudinal edges of the roll of film 21. The tube may be formed from two webs of film 21. In this case, the former forms two longitudinal seals along the opposing edges of the two rolls of film 21.
Packaging apparatus 1 may comprise a flusher 34. Flusher 34 may be configured to flush gas through the tube of film 21 that forms the packaging. The gas flush prevents the tube from collapsing. The gas flush helps to maintain a distance between a product 20 in a tray and the film 21. This helps to improve the hygienic appearance of the film 21 because the film 21 remains untarnished by the product 20. Flusher 34 flushes gas longitudinally through the tube. The gas used for flushing may comprise about 70% oxygen and about 30% carbon dioxide or other suitably modified atmosphere. Additionally, the gas flush may allow the product 20 to be packaged in a modified atmosphere. The gas may help to preserve the product 20, prolonging its shelf life. The desired amount of gas inside each sealed package 23 depends on the type of product 20 and the length of shelf life needed.
Packaging apparatus 1 may comprise a shrinking machine configured to shrink film 21. The shrinking machine may be, for example a shrink tunnel 33, or a hot air tunnel 33. Sealed package 23 may be shrunk in the shrinking machine. The shrinking process may involve heating the sealed package. The package 23 may be heated to a temperature within the range of from about 130° C. to about 150° C. Before sealed package 23 is shrunk, there may be undesirable gas trapped in sealed package 23 along with the product 20. After shrinking, package 23 is referred to as package 23′ (see, e.g.,
Product 20 may be a food product. For example, product 20 may comprise meat, cheese, pizza, ready meals, poultry and fish. Product 20 may be substantially dry, as in the case of cheese. For some products, such as cheese, there is no need for a tray to support the cheese. Alternatively, product 20 may be wet. In this case, it is particularly desirable for product 20 to be disposed in a tray. The packaging process of the invention may be employed to package food products 20 that are to have a shelf life in the region of, for example, from about six days to about 14 days.
While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and the scope of the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 15156800.3 | Feb 2015 | EP | regional |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2016/054054 | 2/26/2016 | WO | 00 |
