METHOD FOR PACKAGING PRODUCTS PRONE TO DECAY

METHODE D'EMBALLAGE DE PRODUITS ENCLINS A POURRIR

English Abstract

A method and apparatus for packaging food products
in a synthetic foil. The method generally comprising
transporting the synthetic foil through a punching device in
which perforations are made in the synthetic foil with high
energy beams to yield a perforated foil. The perforations
are made in the synthetic foil to achieve a perforation
surface per surface unit of the synthetic foil set according
to the food product to be packaged, and the perforation
surface per surface unit of the synthetic foil is achieved
by controlling at least one of the number and intensity of
the high energy beams projected onto the synthetic foil.
The perforated foil are then formed into packages, filled
with the food product, and closed to enclose the food
product.

French Abstract

Ce procédé d'emballage, dans une feuille synthétique, de produits enclins à se gâter, tels que des produits alimentaires, et notamment des légumes et/ou fruits, consiste à perforer la feuille synthétique au cours d'une étape, à convertir cette feuille en un emballage et à la remplir. Ainsi, le procédé consiste à acheminer la feuille à travers une poinçonneuse, de façon que des perforations soient pratiquées dans cette feuille synthétique, à mettre en forme cette feuille en tant qu'emballage possédant les dimensions voulues, à remplir ces emballages à l'aide des produits, et à les fermer.

Claims

9
CLAIMS:
1. A method for continuously forming separate
perforated packages and packaging different types of food
products therein, the method comprising the steps of:
identifying a type of a food product to be
packaged with the separate perforated packages;
transporting a synthetic foil through a punching
device in which perforations are made in the synthetic foil
to yield a perforated foil;
controlling the punching device according to
electronic settings to form the perforations in the
perforated foil to achieve a perforation surface per surface
unit of the synthetic foil according to the type of the food
product identified as to be packaged so as to optimize the
shelf life of the food product when packaged within the
separate perforated packages, the perforation surface per
surface unit of the synthetic foil being achieved by
controlling at least the number of the perforations formed
in the synthetic foil; and then
conveying the perforated foil to means that form
and fill the perforated foil to yield the separate
perforated packages in each of which the food product is
enclosed and a plurality of the perforations are present to
allow each of the separate perforated packages to breathe
while filled with the food product.
2. The method according to claim 1, wherein the
separate perforated packages are formed before being filled
with the food product.
3. An apparatus for performing the method according
to claim 1, wherein the apparatus comprises:

the punching device having means for making the
perforations;
means for transporting the synthetic foil through
the punching device;
means for forming the perforated foil into the
separate perforated packages;
means for filling the perforated foil with the
food product;
means for closing the separate perforated packages
after being filled with the food product; and
means for associating the perforation surface per
surface unit of the synthetic foil with the type of the food
product;
wherein the punching device, the transporting
means, the forming means, the filling means, the closing
means and the associating means are combined as an
integrated assembly within which the separate perforated
packages are continuously formed and the food products are
continuously packaged.
4. The apparatus according to claim 3, wherein the
means for making the perforations comprises means for
generating high energy beams, and the generating means is
controlled by the associating means.
5. The method according to claim 1, further
comprising the step of varying the perforation surface per
surface unit of the synthetic foil by controlling the number
of the perforations formed in the synthetic foil.
6. The method according to claim 1, wherein the
perforation surface per surface unit of the synthetic foil

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is further achieved by also controlling the size of the
perforations formed in the synthetic foil.
7. The method according to claim 1, wherein the types
of food products are chosen from the group consisting of
fruits and vegetables.
8. The method according to claim 1, wherein the
synthetic foil is in the form of separate sheets when
transported to the punching device.
9. The method according to claim 1, wherein the
synthetic foil is in the form of continuous strip when
transported to the punching device, and forming the
perforated foil to yield the separate perforated packages
comprises cutting the continuous strip into separate sheets.
10. The method according to claim 9, wherein forming
the perforated foil to yield the separate perforated
packages comprises double folding the continuous strip to
form a longitudinal edge and then sealing the longitudinal
edge.
11. A method for continuously forming separate
perforated packages and continuously packaging food products
therein, the method comprising the steps of:
identifying a type of a food product to be
packaged with the separate perforated packages;
transporting separate sheets of a synthetic foil
through a punching device in which perforations are made in
the separate sheets with high energy beams to yield separate
perforated sheets;
controlling the punching device according to
electronic settings to form the perforations in the separate

12
sheets of the synthetic foil to achieve a perforation
surface per surface unit of each separate sheet according to
the type of the food product identified as to be packaged
therein so as to optimize the shelf life of the food product
when packaged within the separate perforated packages, the
perforation surface per surface unit of each separate sheet
being achieved by controlling at least the number of the
perforations formed in the separate sheet with the high
energy beams;
conveying and then forming the separate perforated
sheets into the separate perforated packages;
conveying and then filling each of the separate
perforated packages with the food product; and
conveying and then closing the separate perforated
packages to enclose the food product, a plurality of the
perforations being present in each of the separate
perforated packages to allow each of the separate perforated
packages to breathe immediately following closing of the
separate perforated packages and while filled with the food
product.
12. An apparatus for performing the method according
to claim 11, wherein the apparatus comprises:
the punching device having means for generating
the high energy beams;
means for transporting the separate sheets of the
synthetic foil through the punching device;
means for forming the separate perforated sheets
into the separate perforated packages;

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means for filling the separate perforated packages
with the food product;
means for closing the separate perforated packages
after being filled with the food product; and
means for associating the perforation surface per
surface unit of the separate sheets with the type of the
food product;
wherein the punching device, the transporting
means, the forming means, the filling means, the closing
means, and the associating means are combined as an
integrated assembly within which the separate perforated
packages are continuously formed and the food products are
continuously packaged.
13. The method according to claim 11, further
comprising the step of varying the perforation surface per
surface unit of the separate sheets by controlling the
number of the perforations formed in the separate sheets.
14. The method according to claim 11, wherein the
perforation surface per surface unit of each separate sheet
is further achieved by also controlling the size of the
perforations formed in each separate sheet by controlling
the intensity of the high energy beams projected onto each
separate sheet.
15. The method according to claim 11, wherein the
types of food products are chosen from the group consisting
of fruits and vegetables.
16. A method for continuously forming separate
perforated packages and continuously packaging food products
therein, the method comprising the steps of:

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identifying a type of a food product to be
packaged with the separate perforated packages;
transporting a continuous strip of a synthetic
foil through a punching device in which perforations are
made in the synthetic foil with high energy beams to yield a
continuous strip of a perforated foil;
controlling the punching device according to
electronic settings to form the perforations in the
synthetic foil to achieve a perforation surface per surface
unit of the synthetic foil according to the type of the food
product identified as to be packaged therein so as to
optimize the shelf life of the food product when packaged
within the separate perforated packages, the perforation
surface per surface unit of the synthetic foil being
achieved by controlling at least the number of the
perforations formed in the synthetic foil with the high
energy beams;
conveying and then cutting the continuous strip of
the perforated foil into separate perforated sheets, each
separate perforated sheet having a size according to the
type and quantity of the food product to be packaged
therein;
conveying and then forming the separate perforated
sheets into the separate perforated packages;
conveying and then filling each of the separate
perforated packages with the food product; and
conveying and then closing the separate perforated
packages to enclose the food product, a plurality of the
perforations being present in each of the separate
perforated packages to allow each of the separate perforated

15
packages to breathe immediately following closing of the
separate perforated packages and while filled with the food
product.
17. An apparatus for performing the method according
to claim 16, wherein the apparatus comprises:
the punching device having means for generating
the high energy beams;
means for transporting the continuous strip of the
synthetic foil through the punching device;
means for forming the separate perforated sheets
into the separate perforated packages;
means for filling the separate perforated packages
with the food product;
means for closing the separate perforated packages
after being filled with the food product; and
means for associating the perforation surface per
surface unit of the synthetic foil with the type of the food
product;
wherein the punching device, the transporting
means, the forming means, the filling means, the closing
means, and the associating means are combined as an
integrated assembly within which the separate perforated
packages are continuously formed and the food products are
continuously packaged.
18. The method according to claim 16, further
comprising the step of varying the perforation surface per
surface unit of the synthetic foil by controlling the number
of the perforations formed in the synthetic foil.

16
19. The method according to claim 16, wherein the
perforation surface per surface unit of the synthetic foil
is further achieved by also controlling the size of the
perforations formed in the synthetic foil by controlling the
intensity of the high energy beams projected onto the
synthetic foil.
20. The method according to claim 16, wherein the
types of food products are chosen from the group consisting
of fruits and vegetables.

Description

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METHOD FOR PACKAGING PRODUCTS PRONE TO DECAY
BACKGROUND OF THE INVENTION
Field of the Invention
The invention relates to a method for packaging
products prone to decay, such as food products, more
particularly vegetables and/or fruit in a synthetic foil,
wherein the synthetic foil is transported through a punching
device in which the perforations are made in the synthetic
foil, the perforated foil is formed into packages having the
desired dimensions and these packages are filled with the
products and closed, the perforation surface per surface
unit synthetic foil being determined depending upon the
product to be packaged and the perforations being obtained
by means of high energy beams.
Packaging vegetables and/or fruit in packages,
more particularly bags made of synthetic foil, whereby the
synthetic foil is provided with perforations, is known from
WO-A-9322207 and DE-A-1952341.
This way, it is aimed at allowing the package to
"breathe", improving thereby shelf life for the product.
This patent application describes more in detail that the
perforation size, i.e. the size of each perforation combined
with the perforation number should be determined depending
upon the nature of the product to be packaged.
Consequently, this leads to the problem that
another type of package should be used for each type of
product, which involves in practice that a large number of
different types of packages such as bags should be available
in stock. On the other hand, as the package is made in situ
from perforated foil, a large number of different foils

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should be available in stock, each time for the pertaining
products.
The invention aims at offering a method for
packaging food products being prone to decay so as to
alleviate this problem.
BRIEF SUMMARY OF THE INVENTION
The aim is reached according to the invention by
means of a method for packaging products prone to decay,
such as food products, more particularly vegetables and/or
fruit in a synthetic foil, wherein the synthetic foil is
transported through a punching device in which the
perforations are made in the synthetic foil, the perforated
foil is formed into packages having the desired dimensions
and these packages are filled with the products and closed,
the perforation surface per surface unit synthetic foil
being determined depending upon the product to be packaged
and the perforations being obtained by means of high energy
beams, characterized in that the perforation surface per
surface unit of synthetic foil is set by controlling the
number of emerging high energy emitters and/or the beam
intensity.
With this method, it can be achieved that only a
limited number of synthetic foils should be available in
stock, since the perforations are only punched at the start
of the packaging process. The synthetic foil types that
should be available in stock are thereby reduced to the
types of various thickness, colour and/or other quality
requirements, but depend upon the desired perforation, that
can again be punched each time.
The invention also relates to a device for
applying the above-mentioned method, said device being

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characterized by a combination of a feeding device for
feeding a synthetic foil, a device for perforating the
synthetic foil, a device for forming a package from the
perforated synthetic foil, a device for filling the formed
package with products, and a device for sealing the filled
package, said device being characterized in that the various
devices are combined into an integrated device.
Preferably, the device is provided with regulation
elements by means of which the perforation surface per
surface unit is controlled.
An aspect of the invention also relates to a
method for continuously forming separate perforated packages
and packaging different types of food products therein, the
method comprising the steps of: identifying a type of a food
product to be packaged with the separate perforated
packages; transporting a synthetic foil through a punching
device in which perforations are made in the synthetic foil
to yield a perforated foil; controlling the punching device
according to electronic settings to form the perforations in
the perforated foil to achieve a perforation surface per
surface unit of the synthetic foil according to the type of
the food product identified as to be packaged so as to
optimize the shelf life of the food product when packaged
within the separate perforated packages, the perforation
surface per surface unit of the synthetic foil being
achieved by controlling at least the number of the
perforations formed in the synthetic foil; and then
conveying the perforated foil to means that form and fill
the perforated foil to yield the separate perforated
packages in each of which the food product is enclosed and a
plurality of the perforations are present to allow each of
the separate perforated packages to breathe while filled
with the food product.

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An aspect of the invention also relates to a
method for continuously forming separate perforated packages
and continuously packaging food products therein, the method
comprising the steps of: identifying a type of a food
product to be packaged with the separate perforated
packages; transporting separate sheets of a synthetic foil
through a punching device in which perforations are made in
the separate sheets with high energy beams to yield separate
perforated sheets; controlling the punching device according
to electronic settings to form the perforations in the
separate sheets of the synthetic foil to achieve a
perforation surface per surface unit of each separate sheet
according to the type of the food product identified as to
be packaged therein so as to optimize the shelf life of the
food product when packaged within the separate perforated
packages, the perforation surface per surface unit of each
separate sheet being achieved by controlling at least the
number of the perforations formed in the separate sheet with
the high energy beams; conveying and then forming the
separate perforated sheets into the separate perforated
packages; conveying and then filling each of the separate
perforated packages with the food product; and conveying and
then closing the separate perforated packages to enclose the
food product, a plurality of the perforations being present
in each of the separate perforated packages to allow each of
the separate perforated packages to breathe immediately
following closing of the separate perforated packages and
while filled with the food product.
An aspect of the invention also relates to a
method for continuously forming separate perforated packages
and continuously packaging food products therein, the method
comprising the steps of: identifying a type of a food
product to be packaged with the separate perforated

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packages; transporting a continuous strip of a synthetic
foil through a punching device in which perforations are
made in the synthetic foil with high energy beams to yield a
continuous strip of a perforated foil; controlling the
5 punching device according to electronic settings to form the
perforations in the synthetic foil to achieve a perforation
surface per surface unit of the synthetic foil according to
the type of the food product identified as to be packaged
therein so as to optimize the shelf life of the food product
when packaged within the separate perforated packages, the
perforation surface per surface unit of the synthetic foil
being achieved by controlling at least the number of the
perforations formed in the synthetic foil with the high
energy beams; conveying and then cutting the continuous
strip of the perforated foil into separate perforated
sheets, each separate perforated sheet having a size
according to the type and quantity of the food product to be
packaged therein; conveying and then forming the separate
perforated sheets into the separate perforated packages;
conveying and then filling each of the separate perforated
packages with the food product; and conveying and then
closing the separate perforated packages to enclose the food
product, a plurality of the perforations being present in
each of the separate perforated packages to allow each of
the separate perforated packages to breathe immediately
following closing of the separate perforated packages and
while filled with the food product.
BRIEF DESCRIPTION OF THE DRAWINGS
Other features and advantages of the invention
will become evident from the following description referring
to the accompanying drawings, wherein the various method
steps are illustrated.

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DETAILED DESCRIPTION OF THE INVENTION
In the FIGURE, the annotation 1 schematically
illustrates a synthetic foil from stock. This stock may
consist in a synthetic foil roll which is unrolled and is
conveyed as a continuous strip towards a perforation device
2. It is also possible to start from a stock 1 consisting
in separate sheets of synthetic foil, which are conveyed one
by one towards the perforation device 2.
In the perforation device 2, the continuous
synthetic foil strips or separate sheets of synthetic foil
are supplied with perforations. Punching can be done
different ways, for example, with fine needles and similar
means, but preferably use is made of laser beam
perforations. In that aspect, a row of high energy emitters
such as laser beam generators can be mounted in device 2,
which can extend over the whole width of the supplied
synthetic strip or synthetic sheet or over a part of the
width. Preferably, the row of laser beam generators extends
over a small section, seen in the width, since it is in
general sufficient when only part of the package is
perforated. Thereby, the numbers of laser beam generators
can be kept limited. Perforations can be punched in the
synthetic foils through an intermittent activation of the
laser beam generators and the appropriate control of the
laser beam intensity.
Thereby, it is possible to control the perforation
number per surface unit, either by activating or not
activating the laser beam generators, or by setting the
frequency at which the laser beam generators are activated
or both. Moreover, the size of each individual perforation
can be controlled by controlling the intensity for the laser
beam generators. This way, the perforation surface (that is

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the total surface of the perforations) can be set by surface
unit.
As disclosed in WO-A-9322207, it is important to
set the perforation surface for each product type, in order
to reach an optimum effect. By means of the punching device
2 in cooperation with an appropriate controller 7, the total
perforation surface per surface unit can easily be set, via
an electronic way, according to the product that is to be
packaged, in order to obtain an optimum shelf life of the
product to be packaged.
Determining the perforation surface can be done
based on calculations, but this is preferably determined
based on experimental results.
After the synthetic foil is thus provided with
perforations, it is further conveyed in an operation step
towards a device 4 for forming bags. In the case of a
continuous strip, the synthetic foil first passes through a
device 3 in which the strip is cut into separate sheets with
the desired sizes. In the case of sheets, this device 3 can
be omitted.
After these bags have been formed, they are
conveyed further towards a filling machine 5, where the
shaped bags are filled with a measured quantity of food
products, which are also supplied to the filling machine 5.
Further, these filled bags 5 are finally conveyed
towards a closing machine 6, where the bags are closed in an
appropriate way, for example, by means of a heat sealing
equipment.
In another embodiment of the invention, the
packages are formed by double folding part of the synthetic

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foil, viewed in the moving direction, and by closing the
thus formed edge for example through a heat sealing process.
Consecutively or approximately simultaneously with the
longitudinal edge being formed, a transversal edge is
formed, which is designed as the packaging bottom. Under
this form, the thus formed bag is filled with products.
Subsequently, a new transversal edge follows, by which the
formed and filled package is closed and isolated from the
synthetic foil. Preferably in the course of the packaging
closure, the bottom edge of the following package is
simultaneously formed.
It is obvious that the invention is not limited to
the described and illustrated embodiment, but numerous
iftodifications can be made within the scope of the claims.
For example, it is more particularly possible to first form
the packing after the food products have been placed on a
synthetic foil sheet, which actually implies an inversion of
steps 4 and 5.