TECHNICAL FIELD
[0001] The present invention relates to a packaging apparatus for forming sealed packages,
in particular for forming sealed packages filled with a pourable product.
BACKGROUND ART
[0002] As is known, many liquid or pourable food products, such as fruit juice, UHT (ultra-high-temperature
treated) milk, wine, tomato sauce, etc., are sold in packages made of sterilized packaging
material.
[0003] A typical example is the parallelepiped-shaped package for liquid or pourable food
products known as Tetra Brik Aseptic (registered trademark), which is made by sealing
and folding a laminated strip packaging material. The packaging material has a multilayer
structure comprising a base layer, e.g. of paper, covered on both sides with layers
of heat-seal plastic material, e.g. polyethylene. In the case of aseptic packages
for long-storage products, such as UHT milk, the packaging material also comprises
a layer of oxygen-barrier material, e.g. an aluminum foil, which is superimposed on
a layer of heat-seal plastic material, and is in turn covered with another layer of
heat-seal plastic material forming the inner face of the package eventually contacting
the food product.
[0004] Packages of this sort are normally produced on a fully automatic packaging apparatus,
which advances a web of packaging material by means of a conveying device through
a sterilization unit for sterilizing the web of packaging material, e.g. by means
of chemical sterilization (e.g. by applying a chemical sterilizing agent, such as
a hydrogen peroxide solution) or physical sterilization (e.g. by means of an electron
beam). Then, the sterilized web of packaging material is maintained and advanced within
an isolation chamber delimiting an inner environment, and is folded and sealed longitudinally
within the inner environment to form a tube, which is further fed along a vertical
advancing direction.
[0005] In order to complete the forming operations, the tube is filled through a filling
pipe with a pourable food product, and is transversally sealed and subsequently cut
along equally spaced transversal cross sections within a package forming unit of the
packaging apparatus during advancement along the vertical advancing direction.
[0006] Pillow packages are so obtained within the packaging apparatus, each pillow package
having a longitudinal sealing band and a top transversal sealing band and a bottom
transversal sealing band.
[0007] A type of packaging apparatus comprises:
- a delimiting element being, in use, arranged within the tube and dividing the tube
in a first space being in fluidic connection with the inner environment and a second
space being arranged downstream of the first space; and
- a sterile gas supply device configured to direct a sterile gas into the second space
and to control a pressure of the sterile gas being greater than the pressure within
the isolation chamber.
[0008] The delimiting element comprises a passage through which the filling tube extends
keeping an annular space between the filling tube and a rim delimiting the passage.
[0009] Furthermore, the sterile gas supply device comprises a gas supply pipe coaxial to
the filling pipe. In particular, the filling pipe extends partially within the gas
supply pipe and out of the gas supply pipe and through the passage so that, in use,
the sterile gas to be fed into the second space flows through a ring-shaped channel
as delimited by the filling pipe and the gas supply pipe.
[0010] In order to accommodate for the inherent fluctuations occurring during the packaging
process, the delimiting element is moveable along a first direction and a second direction
opposite to the first direction. Both the first direction and the second direction
being parallel to the vertical advancement direction.
[0011] In use, the delimiting element is lifted by means of the sterile gas being present
within the second space and the delimiting element is movable along the first direction
until a first engagement portion of the delimiting element abuts against a first abutment
portion of the gas supply pipe and is movable along the second direction until a second
engagement portion of the delimiting element abuts against a second abutment portion
of a support element being arranged below the delimiting element.
[0012] It has been observed that when the first engagement portion is detached from the
first abutment portion a leakage flow of gas from the second space into the inner
environment occurs through the ring-shaped channel and a space being present between
the delimiting element and the gas supply pipe, while there is no leakage flow when
the first engagement portion abuts against the first abutment portion.
[0013] It has been further observed that such a behavior leads to the presence of instabilities,
which increase the complexity of the control of the overall packaging process.
[0014] Therefore, a need is felt in the sector to improve the packaging apparatuses. In
particular, so as to overcome at least one of the above-mentioned disadvantages.
DISCLOSURE OF INVENTION
[0015] It is therefore an object of the present invention to provide in a straightforward
and low-cost manner an improved packaging apparatus.
[0016] According to the present invention, there is provided a packaging apparatus as claimed
in claim 1.
[0017] Further advantageous embodiments of the packaging apparatus according to the invention
are specified in the dependent claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] A non-limiting embodiment of the present invention will be described by way of example
with reference to the accompanying drawings, in which:
Figure 1 is a schematic view of a packaging apparatus according to the present invention,
with parts removed for clarity;
Figure 2 is a schematic view of details of the packaging apparatus of Figure 1, with
parts removed for clarity;
Figure 3 is an enlarged partially sectionized view of a portion of the packaging apparatus
of Figure 1, with parts removed for clarity; and
Figure 4 is a perspective view of a detail of the portion of Figure 3, with parts
removed for clarity; and
Figure 5 is an enlarged sectionized view of the portion of Figure 3, with parts removed
for clarity.
BEST MODES FOR CARRYING OUT THE INVENTION
[0019] Number 1 indicates as a whole a packaging apparatus for producing sealed packages
2 of a pourable food product, in particular a sterilized and/or a sterile-processed
pourable food product, such as pasteurized milk or fruit juice, from a tube 3 of a
web 4 of packaging material. In particular, in use, tube 3 extends along a longitudinal
axis L, in particular, axis L having a vertical orientation.
[0020] Web 4 of packaging material has a multilayer structure (not shown), and comprises
at least one layer of fibrous material, such as e.g. a paper or cardboard layer, and
at least two layers of heat-seal plastic material, e.g. polyethylene, interposing
the layer of fibrous material in between one another. One of these two layers of heat-seal
plastic material defining the inner face of package 2 eventually contacting the pourable
product.
[0021] Preferably but not necessarily, web 4 also comprises a layer of gas- and light-barrier
material, e.g. aluminum foil or ethylene vinyl alcohol (EVOH) film, in particular
being arranged between one of the layers of the heat-seal plastic material and the
layer of fibrous material. Preferentially but not necessarily, web 4 also comprises
a further layer of heat-seal plastic material being interposed between the layer of
gas- and light-barrier material and the layer of fibrous material.
[0022] A typical package 2 obtained by packaging apparatus 1 comprises a sealed longitudinal
seam portion 5 and a pair of transversal seal portions 6, in particular a top transversal
seal portion and a bottom transversal seal portion (i.e. one transversal seal portion
6 at an upper portion of package 2 and another transversal seal portion 6 at a lower
portion of package 2).
[0023] With particular reference to Figures 1 and 2, packaging apparatus 1 comprises:
- a conveying device 7 configured to advance web 4 (in a manner known as such) along
a web advancement path P from a delivery station 8 to a tube forming station 9, at
which, in use, web 4 is formed into tube 3;
- an isolation chamber 10 having an inner environment 11, in particular an inner sterile
environment, containing (comprising) a sterile gas, in particular sterile air, and
being separated from an outer environment 12;
- a tube forming and sealing device 13 being at least partially arranged within isolation
chamber 10 and being adapted to form and longitudinally seal tube 3, in particular
at tube forming station 9, within inner environment 11 and from the, in use, advancing
web 4;
- a filling device 14 for filling tube 3 with the pourable product; and
- in particular, a package forming unit 15 adapted to form, to transversally seal and,
preferably but not necessarily to transversally cut the, in use, advancing tube 3
for forming packages 2.
[0024] Preferably but not necessarily, packaging apparatus 1 also comprises a sterilizing
unit (not shown and known as such) adapted to sterilize, in particular by means of
chemical and/or physical sterilization, the, in use, advancing web 4 at a sterilization
station, in particular the sterilization station being arranged upstream of tube forming
station 9 along web advancement path P.
[0025] Preferentially but not necessarily, conveying device 7 is configured to advance tube
3 and, in particular also any intermediate of tube 3, in a manner known as such along
a tube advancement path Q, in particular from tube forming station 9 to and at least
partially through package forming unit 15.
[0026] In particular, with the wording intermediates of tube 3 any configuration of web
4 is meant prior to obtaining the tube structure and after folding of web 4 by tube
forming device 13 has started. In other words, the intermediates of tube 3 are a result
of the gradual folding of web 4 so as to obtain tube 3, in particular by overlapping
the lateral edges of web 4 with one another.
[0027] Preferentially but not necessarily, tube forming and sealing device 13 comprises
a tube forming unit 22 at least partially, preferably fully, arranged within isolation
chamber 10, in particular at tube forming station 9, and being adapted to (configured
to) gradually fold the advancing web 4 into tube 3, in particular by overlapping the
lateral edges with one another, for forming a longitudinal seam portion 23 of tube
3. In particular, tube forming unit 22 extends along a longitudinal axis M, in particular
having a vertical orientation.
[0028] In particular, seam portion 23 extends from an initial level (not specifically shown)
into a downward direction along tube advancement path Q. In other words, the initial
level is at the position at which the lateral edges start to overlap one another for
forming seam portion 23.
[0029] In particular, at least a portion of tube advancement path Q lies within isolation
chamber 10 (in particular, within inner environment 11) and, even more particular
another portion of tube advancement path Q lies within package forming unit 15.
[0030] In more detail, axis L and axis M are parallel to one another. In even more detail,
tube forming unit 22 defines, in use, axis L of tube 3.
[0031] Preferentially but not necessarily, tube forming unit 22 comprises at least two forming
ring assemblies 24 and 25, in particular arranged within isolation chamber 10 (in
particular, within inner environment 11), being adapted to gradually fold in cooperation
with one another web 4 into tube 3, in particular by overlapping the lateral edges
of web 4 with one another.
[0032] Even more particular, forming ring assemblies 24 and 25 are spaced apparat from and
parallel to one another.
[0033] Preferentially but not necessarily, tube forming and sealing device 13 also comprises
a sealing unit adapted to (configured to) longitudinally seal tube 3 along seam portion
23. In other words, in use, seam portion 23 formed by tube forming unit 22 is sealed
by activation of the sealing unit.
[0034] Preferentially but not necessarily, the sealing unit is at least partially positioned
within isolation chamber 10.
[0035] It must be noted that the respective longitudinally sealed seam portion 5 of the
single packages 2 result from cutting tube 3. In other words, the respective seam
portions 5 of the single packages 2 are respective sections of seam portion 23 of
tube 3.
[0036] Furthermore, the sealing unit comprises a sealing head 29 arranged within isolation
chamber 10 and being adapted to (configured to) transfer thermal energy to tube 3,
in particular to seam portion 23, for longitudinally sealing tube 3, in particular
seam portion 23. Sealing head 29 can be of any type. In particular, sealing head 29
can be of the kind operating by means of induction heating and/or by a stream of a
heated gas and/or by means of ultrasound and/or by laser heating and/or by any other
means.
[0037] Preferentially but not necessarily, the sealing unit also comprises a pressing assembly
(only partially shown) adapted to exert a mechanical force on tube 3, in particular
onto seam portion 23, so as to ensure the longitudinal sealing of tube 3 along seam
portion 23.
[0038] With particular reference to Figures 1 to 3 and 5, filling device 14 comprises a
filling pipe 31 for directing the pourable product, in use, into tube 3. In particular,
filling pipe 31 is in fluid connection or is controllable to be in fluid connection
with a pourable product storage tank (not shown and known as such), which is adapted
to store/provide for the pourable product, in particular the sterilized and/or sterile-processed
pourable food product, to be packaged.
[0039] Preferentially but not necessarily, filling pipe 31 is, in use, at least partially
placed within tube 3.
[0040] In particular, filling pipe 31 comprises a linear main pipe portion 32 extending
within and parallel to tube 3, i.e. parallel to axis M and/or axis L.
[0041] Preferentially but not necessarily, main pipe portion 32 comprises an upper section
33 and a lower section 34 removably coupled to one another. In further detail, lower
section 34 comprises an outlet opening from which the pourable product is fed, in
use, into tube 3.
[0042] According to the preferred non-limiting embodiment as shown in Figure 2, package
forming unit 15 comprises a plurality of pairs of at least one respective operative
assembly 35 (only one shown) and at least one counter-operative assembly 36 (only
one shown); and
- in particular, a conveying device (not shown and known as such) adapted to advance
the respective operative assemblies 35 and the respective counter-operative assemblies
36 of the pairs along respective conveying paths.
[0043] In more detail, each operative assembly 35 is adapted to cooperate, in use, with
the respective counter-operative assembly 36 of the respective pair for forming a
respective package 2 from tube 3. In particular, each operative assembly 35 and the
respective counter-operative assembly 36 are configured to shape, to transversally
seal and, preferably but not necessarily also to transversally cut, tube 3 for forming
packages 2.
[0044] In further detail, each operative assembly 35 and the respective counter-operative
assembly 36 are adapted to cooperate with one another for forming a respective package
2 from tube 3 when advancing along a respective operative portion of the respective
conveying path. In particular, during advancement along the respective operative portion
each operative assembly 35 and the respective counter-operative assembly 36 advance
parallel to and in the same direction as tube 3.
[0045] In even more detail, each operative assembly 35 and the respective counter-operative
assembly 36 are configured to contact tube 3 when advancing along the respective operative
portion of the respective conveying path.
[0046] More specifically, each operative assembly 35 and counter-operative assembly 36 comprises:
- a half-shell 37 adapted to contact tube 3 and to at least partially define the shape
of packages 2;
- one of a sealing element 38 or a counter-sealing element 39, adapted to transversally
seal tube 3 in a known manner between adjacent packages 2 for obtaining transversal
seal portions 6; and
- preferably but not necessarily, one of a cutting element (not shown and known as such)
or a counter-cutting element (not shown and known as such) for transversally cutting
tube 3 between adjacent packages 2, in particular between the respective transversal
seal portions 6, in a manner known as such.
[0047] In particular, each half-shell 37 is adapted to be controlled between a working position
and a rest position by means of a driving assembly (not shown). In particular, each
half-shell 37 is adapted to be controlled into the working position with the respective
operative assembly 35 or the respective counter-operative assembly 36, in use, advancing
along the respective operative portion.
[0048] With particular reference to Figures 1 and 2, isolation chamber 10 comprises an outlet-opening
for allowing tube 3 to exit isolation chamber 10 during advancement along path Q.
In particular, the outlet-opening is arranged downstream of tube forming station 9
along path Q.
[0049] Preferably but not necessarily, the outlet-opening is arranged in the area of a downstream
(end) portion of isolation chamber 10.
[0050] Preferentially but not necessarily, isolation chamber 10 also comprises an inlet-opening,
opposite to the outlet-opening, and configured to allow entrance of (sterile) web
4 into isolation chamber 10. In particular, the inlet-opening is positioned in an
upstream portion of isolation chamber 10.
[0051] According to the preferred non-limiting embodiment disclosed, inner environment 11
comprises (i.e. contains) the sterile gas, in particular the sterile air, at a given
pressure. Preferentially but not necessarily, the given pressure is (slightly) above
ambient pressure for reducing the risk of any contaminants and/or contaminations entering
inner environment 11. In particular, the given pressure is about 100 Pa to 500 Pa
(0,001 bar to 0,005 bar) above ambient pressure.
[0052] According to the present invention and with particular reference to Figures 1 to
5, packaging apparatus 1 also comprises a delimiting element 45 moveably arranged,
in use, within tube 3 and designed to divide tube 3, in use, into a first space 46
and a second space 47.
[0053] According to a preferred non-limiting embodiment, delimiting element 45 is arranged
within isolation chamber 10, in particular upstream of the outlet-opening along tube
advancement path Q.
[0054] In more detail, first space 46 is delimited by tube 3, in particular the walls of
tube 3, and delimiting element 45. Furthermore, first space 46 opens up into inner
environment 11. Even more particular, delimiting element 45 delimits first space 46
at a downstream portion (with respect to tube advancement path Q), in particular a
bottom portion, of first space 46 itself.
[0055] In more detail, second space 47 is delimited, in use, by tube 3, in particular the
walls of tube 3, delimiting element 45 and the transversal seal portion 6 of one respective
package 2 (to be formed).
[0056] In other words, second space 47 extends in a direction parallel to tube advancement
path Q (i.e. parallel to axis L) from delimiting element 45 to transversal seal portion
6.
[0057] In even other words, delimiting element 45 delimits second space 47 at an upstream
portion (with respect to tube advancement path Q), in particular an upper portion,
of second space 47 itself; and transversal seal portion 6 delimits second space 47
at a downstream portion (with respect to tube advancement path Q), in particular a
bottom portion, of second space 47 itself.
[0058] In further detail, first space 46 is arranged upstream of second space 47 along tube
advancement path Q. Even more particular, first space 46 is arranged upstream of delimiting
element 45 along tube advancement path Q and second space 47 is arranged downstream
of delimiting element 45 along tube advancement path Q. In the specific example shown,
second space 47 is arranged below first space 46.
[0059] Advantageously and with particular reference to Figures 1 and 2, packaging apparatus
1 comprises a sterile gas supply device 48 (only partially shown to the extent necessary
for the comprehension of the invention disclosed) configured to at least direct a
main flow of sterile gas into second space 47 in such a manner that the gas pressure
of the sterile gas within second space 47 is higher than the gas pressure of the sterile
gas present within isolation chamber 10 and/or inner environment 11 and/or first space
46.
[0060] Preferentially but not necessarily, sterile gas supply device 48 is also adapted
to (configured to) direct, in use, a further flow of sterile gas (not specifically
shown) into isolation chamber 10 and/or inner environment 11.
[0061] In particular, second space 47 defines a high-pressure zone within tube 3 and first
space 46 defines a low-pressure zone within tube 3.
[0062] In the context of the present application, high-pressure zone is to be understood
such that the internal pressure lies in a range of about 5kPa to 40kPa (0,05 bar to
0,40 bar), in particular of about 10kPa to 30 kPa (0,10 bar to 0,30 bar) above ambient
pressure (i.e. the pressure within second space 47 lies in a range of about 5kPa to
40kPa (0,05 bar to 0,40 bar), in particular of about 10kPa to 30 kPa (0,10 bar to
0,30 bar) above ambient pressure). In other words, second space 47 is overpressurized
with respect to first space 46.
[0063] Low-pressure zone is to be understood such that the pressure is slightly higher than
the ambient pressure. In particular, only slightly higher than the ambient pressure
means that the pressure lies preferably in a range between 100 Pa to 500 Pa (0,001
bar to 0,005 bar) above ambient pressure.
[0064] Preferably but not necessarily, first space 46 is in (direct) fluidic connection
with inner environment 11. Thus, sterile gas present in the first space 46 can flow
to inner environment 11.
[0065] In particular, tube 3 (and its intermediates) lie(s) at least partially within isolation
chamber 10 (in particular, within inner environment 11).
[0066] Preferentially, the pressure inside first space 46 (substantially) equals the given
pressure present in isolation chamber 10, in particular in inner environment 11.
[0067] According to a preferred non-limiting embodiment, delimiting element 45 is arranged,
in use, downstream of the above-mentioned initial level along tube advancement path
Q. In other words, delimiting element 45 is positioned below the point from which
seam portion 23 extends along a downstream direction (with respect to tube advancement
path Q). In even other words, delimiting element 45 is arranged below the position
from which the lateral edges of web 4 are superimposed for forming seam portion 23.
[0068] Furthermore, in use, filling device 14, in particular filling pipe 31, is adapted
to (configured to) direct the pourable product into second space 47. Thus, in use,
second space 47 contains the pourable product and the pressurized sterile gas directed
into the second space 47. The pressurized sterile gas provides for the required hydrostatic
force needed for a correct forming of packages 2.
[0069] Advantageously but not necessarily and with particular reference to Figures 1 to
5, sterile gas supply device 48 comprises a gas supply pipe 49 configured to direct
the main flow of sterile gas into second space 47; in other words, in use, the main
flow of sterile gas enters into second space 47 through gas supply pipe 49.
[0070] In particular, gas supply pipe 49 comprises an outlet mouth 50 configured to allow
for the main flow of sterile gas exiting gas supply pipe 49, and in particular entering
into second space 47.
[0071] Preferentially but not necessarily, gas supply pipe 49 also comprises a collar portion
51 surrounding and/or delimiting outlet mouth 50.
[0072] In particular, gas supply pipe 49, in particular outlet mouth 50 and/or collar portion
51, is arranged upstream of delimiting element 45 along tube advancement path Q.
[0073] Preferentially but not necessarily, gas supply pipe 49 comprises at least a main
portion 52, which, in use, extends within tube 3. In particular, main portion 52 extends
parallel, preferentially but not necessarily coaxial, to main pipe portion 32.
[0074] According to a preferred non-limiting embodiment, main portion 52 carries and/or
comprises outlet mouth 50 and/or collar portion 51.
[0075] In the specific example shown, filling pipe 31 extends at least partially within
gas supply pipe 49. Alternatively, gas supply pipe 49 could at least partially extend
within filling pipe 31.
[0076] In more detail, at least main pipe portion 32 extends at least partially within main
portion 52.
[0077] In particular, the cross-sectional diameter of main pipe portion 32 is smaller than
the cross-sectional diameter of main portion 52.
[0078] Preferentially but not necessarily, gas supply pipe 49 and filling pipe 31 define/delimit
an annular conduit 53 for the main flow of sterile gas to be fed into second space
47. In particular, annular conduit 53 is delimited by the inner surface of gas supply
pipe 49 and the outer surface of filling pipe 31.
[0079] According to a preferred non-limiting embodiment, delimiting element 45 comprises
a passage 57, in particular having a circular cross-sectional profile, configured
to allow the main flow to enter into second space 47 through passage 57. In particular,
passage 57 is, in use, arranged substantially coaxial to filling pipe 31 and/or gas
supply pipe 49, in particular outlet mouth 50, and/or longitudinal axis M and/or longitudinal
axis L.
[0080] Preferentially but not necessarily, filling pipe 31, in particular main pipe portion
32, extends through passage 57 into second space 47.
[0081] Preferentially but not necessarily, a central rim portion 58 of delimiting element
45 delimits passage 57 and central rim portion 58 defines and/or delimits together
with filling pipe 31, in particular main pipe portion 32, a ring-shaped channel 59
through which, in use, the main flow of sterile gas enters into second space 47.
[0082] In particular, in use, the main flow of gas exits from gas supply pipe 49 through
outlet mouth 50 and enters into second space 47 through ring-shaped channel 59.
[0083] Advantageously, delimiting element 45 is arranged such that delimiting element 45
is adapted to move along a first direction D1 and a second direction D2 being opposite
to first direction D1. First direction D1 and second direction D2 being (substantially)
parallel to longitudinal axis L and/or tube 3 and/or longitudinal axis M. Furthermore,
delimiting element 45 is adapted to (configured to) move between at least a first
position and a second position, in particular a first end position and a second end
position. In particular, in use, when moving along first direction D1 and along second
direction D2 delimiting element 45 moves respectively towards and away from gas supply
pipe 49.
[0084] According to a preferred non-limiting embodiment, the first position is upstream
of the second position along tube advancement path Q. In the particular non-limiting
embodiment shown, delimiting element 45 is configured to move downwards from the first
position to the second position and upwards from the second position to the first
position.
[0085] In particular as will be disclosed in the following, the first position and the second
position of delimiting element 45 are delimited and/or defined by respective parts
of packaging apparatus 1.
[0086] According to a preferred non-limiting embodiment, delimiting element 45 is also adapted
to move along a third direction D3 and a fourth direction D4 being opposite to third
direction D3. Third direction D3 and fourth direction D4 are transversal, in particular
perpendicular, to longitudinal axis L and/or longitudinal axis M and/or first direction
D1 and/or second direction D2.
[0087] Advantageously, delimiting element 45 comprises a main engagement portion 60 configured
to abut against a main abutment portion 61 of gas supply pipe 49 or of filling pipe
31, in the specific case shown in Figures 1 to 5 of gas supply pipe 49, with delimiting
element 45 being in the first position.
[0088] Preferentially but not necessarily, main abutment portion 61 and/or main engagement
portion 60 have an annular shape.
[0089] Advantageously, main abutment portion 61 and/or main engagement portion 60 are designed
such that one or more openings 62 and/or one or more channels are present between
main abutment portion 61 and main engagement portion 60 with delimiting element 45
being in the first position.
[0090] Advantageously, openings 62 and/or the channels are configured such to establish
a fluid connection between inner environment 11 and gas supply pipe 49 and/or second
space 47 through the channels and/or openings 62, in particular so as to allow, in
use, for the occurrence of an auxiliary flow of gas between main abutment portion
61 and main engagement portion 60 also with delimiting element 45 being in the first
position. In this way, it is guaranteed independently of the position of the delimiting
element 45 that there is the presence of the auxiliary flow. Furthermore, this means
that no changes between the presence of the auxiliary flow and the complete interruption
occurs as it is the case with respect to the state-of-the-art package apparatus as
described in the introductive part. It should be noted that the effective auxiliary
flow is dependent on the distance of delimiting element 45 from main abutment portion
61, however, these variations introduce significantly less instability than the case
in which sometimes there is an auxiliary flow and other times there is not.
[0091] Preferentially but not necessarily, collar portion 51 comprises main abutment portion
61 with main abutment portion 61 facing delimiting element 45, in particular main
engagement portion 60.
[0092] According to a preferred non-limiting embodiment, delimiting element 45 comprises
a main portion 63 facing gas supply pipe 49, in particular outlet mouth 50 and/or
collar portion 51. In particular, main portion 63 carries and/or comprises and/or
supports main engagement portion 60.
[0093] Preferentially but not necessarily, main portion 63 comprises and/or is provided
with passage 57.
[0094] According to a preferred non-limiting embodiment and with particular reference to
Figure 4, delimiting element 45 comprises one or more spacer elements 64 facing and
protruding towards main abutment portion 61 and/or gas supply pipe 49. In particular,
spacer elements 64 carry and/or comprise and/or define, in particular in cooperation,
main engagement portion 60.
[0095] In particular, spacer elements 64 protrude from main portion 62.
[0096] Preferentially but not necessarily, each spacer element 64 has an arc-shaped profile.
[0097] Preferentially but not necessarily, spacer elements 64 surround passage 58 and are
spaced apart from one another around passage 58 so as to form openings 62. In particular,
neighboring spacer elements 64 do not contact one another in order to form openings
62.
[0098] According to an alternative embodiment not shown, neighboring elements 64 could be
connected with one another by means of a bridge portion also partially delimiting
the respective opening 62.
[0099] In use, with delimiting element 45 being in the first position spacer elements 64
guarantee that there is a space between main portion 63 and collar portion 51 and
openings 62 guarantee that the auxiliary flow of sterile gas flows also with delimiting
element 45 being in the first position.
[0100] Alternatively or in addition, main engagement portion 60 and/or main abutment portion
61 comprises one or more grooves defining the one or more channels.
[0101] According to a preferred non-limiting embodiment and with particular reference to
Figures 3 and 5, packaging apparatus 1 further comprises a support element 65 having
an auxiliary abutment portion 66 and delimiting element 45 comprises an auxiliary
engagement portion 67, in particular opposite to main engagement portion 60, configured
to abut against auxiliary abutment portion 66 with delimiting element 45 being in
the second position.
[0102] In particular, delimiting element 45 is interposed between main abutment portion
61 and auxiliary abutment portion 66. Even more particular, in use, when delimiting
element 45 moves along first direction D1 and second direction D2, delimiting element
45 moves towards respectively main abutment portion 61 and auxiliary abutment portion
66.
[0103] According to the non-limiting embodiment shown, delimiting element 45 is interposed
between gas supply pipe 49 and support element 65. Thus, movement of delimiting element
45 along first direction D1 and second direction D2 is delimited by respectively and
between gas supply pipe 49 and support element 65.
[0104] Preferentially but not necessarily, support element 65 is connected to filling pipe
31 and/or gas supply pipe 49. In the non-limiting embodiment shown, filling pipe 31
is connected to filling pipe 31, in particular main pipe portion 32, and protrudes
towards gas supply pipe 49.
[0105] According to a preferred non-limiting embodiment, a first end portion 68 of support
element 65 is connected to filling pipe 31 and a second end portion 69 of support
element 65 opposite to first end portion 68 comprises auxiliary abutment portion 66.
[0106] In particular, when sterile gas supply device 48 is deactivated second space 47 does
not contain the pressurized sterile gas, delimiting element 45 is supported by and/or
"sits" on support element 65.
[0107] According to a preferred non-limiting embodiment, support element 65 has a truncated
cone shape and is hollow. In particular, support element 65 also comprises a plurality
of apertures 70 for the main flow of the sterilized gas.
[0108] According to a preferred non-limiting embodiment and with particular reference to
Figures 2 and 5, delimiting element 45 is designed to provide, in use, and in collaboration
with tube 3 for at least one fluidic channel 71, in particular having an annular shape,
for fluidically connecting second space 47 with first space 46 allowing for, in use,
a direct leakage flow of sterile gas from second space 47 into first space 46. In
particular, in use, the sterile gas leaks from second space 47 (the high-pressure
zone) to first space 46 (the low-pressure zone) through fluidic channel 71. By providing
for fluidic channel 71 it is possible to control the gas pressure within second space
47 with an increased accuracy.
[0109] Preferentially but not necessarily, in use, delimiting element 45 is designed such
that, in use, fluidic channel 71 is provided by a gap between the inner surface of
tube 3 and delimiting element 45, in particular a peripheral portion of delimiting
element 45.
[0110] According to a preferred non-limiting embodiment, delimiting element 45 has a radial
extension being smaller than the inner diameter of tube 3.
[0111] Preferentially but not necessarily, sterile gas supply device 48 is configured to
allow for a variable main flow of sterile gas (i.e. adapted to control varying flow
rates) by maintaining a substantially constant gas pressure within second space 47
at various flow rates.
[0112] Preferentially but not necessarily, sterile gas supply device 48 is adapted to vary
the main flow of sterile gas in dependence of the volume of the sterile gas flowing
from second space 47 to first space 46, in particular through at least fluidic channel
71.
[0113] Preferentially but not necessarily, sterile gas supply device 48 is adapted to (configured
to) control the gas pressure within second space 47 to range between 5 kPa to 40 kPa
(0,05 bar to 0,40 bar), in particular between 10 kPa to 30 kPa (0,10 bar to 0,30 bar),
above ambient pressure.
[0114] Advantageously but not necessarily and with particular reference to Figures 1 and
2, sterile gas supply device 48 comprises a closed sterile gas circuit from inner
environment 11 into second space 47 and back into inner environment 11. This allows
a simplified overall construction of packaging apparatus 1, in particular related
to the control and the supply of the sterile gas.
[0115] According to the preferred non-limiting embodiment disclosed, sterile gas supply
device 48 is adapted to withdraw sterile gas from inner environment 11, to pressurize
(to compress) the sterile gas and to direct the pressurized (compressed) sterile gas
into second space 47.
[0116] Preferentially but not necessarily, sterile gas supply device 48 comprises at least
one pumping device 74 configured to withdraw sterile gas from inner environment 11,
to pressurize (to compress) the sterile gas and to direct the pressurized sterile
gas into second space 47.
[0117] Preferentially but not necessarily, pumping device 74 is a rotary machine, even more
particular a compressor.
[0118] Preferentially but not necessarily, sterile gas supply device 48 also comprise:
- a gas conduit 75 being in direct fluidic connection with pumping device 74 and gas
supply pipe 49; and
- a gas conduit 76 being in direct fluidic connection with inner environment 11 and
pumping device 74.
[0119] Thus, in use, sterile gas is withdrawn from inner environment 11 through gas conduit
76, is pressurized (compressed) by pumping device 74 and is then directed into second
space 47 through gas conduit 75 and gas supply pipe 49.
[0120] In use, packaging apparatus 1 forms packages 2 filled with a pourable product. In
particular, packaging apparatus 1 forms packages 2 from tube 3 formed from web 4,
tube 3 being continuously filled with the pourable product.
[0121] In more detail, operation of packaging apparatus 1 comprises:
- a first advancement step for advancing web 4 along path P;
- a tube forming and sealing step during which web 4 is formed into tube 3 and tube
3 is longitudinally sealed, in particular along seam portion 23;
- a second advancement step during which tube 3 is advanced along path Q;
- a filling step during which the pourable product is filled into tube 3; and
- a package forming step during which packages 2 are formed from tube 3, in particular
by shaping (respective (lower) portions) of tube 3 and transversally sealing and cutting
tube 3.
[0122] In further detail, the tube forming and sealing step comprises the sub-step of gradually
overlapping the lateral edges of tube 3 with one another for forming seam portion
23 and the sub-step of longitudinally sealing tube 3.
[0123] The filling step comprises the sub-step of directing the pourable product through
filling pipe 31 into second space 47.
[0124] During the package forming step, packages 2 are formed by operation of package forming
unit 15, which receives tube 3 after the tube forming and sealing step. In particular,
during the package forming step operative assemblies 35 and counter-operative assemblies
36 advance along their respective conveying paths. When operative assemblies 35 and
their respective counter-operative assemblies 36 advance along their respective operative
portions, operative assemblies 35 and the respective counter-operative assemblies
36 cooperate with one another for shaping, transversally sealing and, preferably but
not necessarily, transversally cutting advancing tube 3 so as to form packages 2.
During the package forming step, the pourable product is directed into second space
47 so as to obtain filled packages 2.
[0125] Operation of packaging apparatus 1 also comprises a pressurizing step during which
sterile gas, in particular the pressurized (compressed) sterile gas is directed into
second space 47.
[0126] In more detail, during the pressurizing step, sterile gas is directed, in particular
continuously directed, into second space 47 for obtaining a gas pressure within second
space 47 which ranges between 5 kPa to 40 kPa (0,05 bar to 0,40 bar), in particular
between 10 kPa to 30 kPa (0,10 bar to 0,30 bar), above ambient pressure.
[0127] In particular, second space 47 contains the pourable product and the pressurized
sterile gas.
[0128] Preferentially but not necessarily, during the pressurizing step the auxiliary flow
of sterile gas flows between main abutment portion 61 and main engagement portion
60 independently of the position of delimiting element 45 between the first portion
and the second position.
[0129] Preferentially but not necessarily, the leakage flow of sterile gas is established
from second space 47 to first space 46 through fluidic channel 71.
[0130] According to a preferred non-limiting embodiment, during the pressurizing step, the
sterile gas is withdrawn from isolation chamber 10, in particular from inner environment
11, is pressurized (compressed) and then directed, in particular continuously directed,
into second space 47.
[0131] In even further detail, during the pressurizing step, pumping device 74 withdraws
the sterile gas from isolation chamber 10, in particular from inner environment 11,
pressurizes (compresses) the sterile gas and directs the pressurized (compressed)
gas through gas supply pipe 49 into second space 47.
[0132] The advantages of packaging apparatus 1 according to the present invention will be
clear from the foregoing description.
[0133] In particular, by providing for openings 62 and/or the channels it is guaranteed
that there is always an auxiliary gas flow between main abutment portion 61 and main
engagement portion 60 even when delimiting element 45 is in the first position. This
increases the stability of the whole system as the complete shut-off of the auxiliary
flow (as in the state-of-art packaging apparatuses) decreases the stability. Accordingly,
the control of packaging apparatus 1 is facilitated with respect to the state-of-the-art
packaging apparatuses.
[0134] Clearly, changes may be made to packaging apparatus 1 as described herein without,
however, departing from the scope of protection as defined in the accompanying claims.
[0135] According to an alternative embodiment not shown, gas supply pipe 49 could take the
place of filling pipe 31 and filling pipe 31 could take the place of gas supply pipe
49.