TECHNICAL FIELD
[0001] The present invention relates to a buffer unit for a packaging apparatus for producing
sealed packages from a web of packaging material and being filled with a pourable
product, in particular a pourable food product.
[0002] Advantageously, the present invention also relates to a packaging apparatus for producing
sealed packages from a web of packaging material and being filled with a pourable
product, in particular a pourable food product.
[0003] Advantageously, the present invention also relates to a method for producing sealed
packages from a web of packaging material and being filled with a pourable product,
in particular a pourable food product.
BACKGROUND ART
[0004] As is known, many liquid or pourable products, such as fruit juice, UHT (ultra-high-temperature
treated) milk, cream, water, wine, tomato sauce, salt, sugar, etc., are sold in packages
made of a sterilized multilayer packaging material.
[0005] 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 multilayer packaging material. The multilayer packaging material comprises
at least a 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.
[0006] In the case of aseptic packages for long-storage products, such as UHT milk, the
multilayer packaging material 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.
[0007] Typically, the multilayer packaging material 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.
[0008] Often the multilayer packaging material is provided in the form of a web of packaging
material, in particular having a succession of repeated patterns, each pattern defining
the pattern of one respective single package obtained at the end of the packaging
process.
[0009] Packages of this sort are normally produced on a fully automatic packaging apparatus,
which comprises a conveying device for advancing the web of packaging material along
an advancement path, a sterilization unit for sterilizing the packaging material,
a tube forming and sealing device arranged within an isolation chamber and configured
to form a tube from the advancing packaging material and to longitudinally seal the
tube, a filling device for directing the pourable product into the tube and a package
forming unit configured to form and to transversally seal and cut the tube for obtaining
the single packages.
[0010] Typically the web of packaging material is provided in the form of a reel, which
at some point of the operation of the packaging apparatus is about to exhaust. In
order to avoid the need to interrupt the production, a typical packaging apparatus
typically comprises a splicing unit for splicing a new web of packaging material to
the web of packaging material in use. This, however, requires the portion of the web
of packaging material in use, which will be spliced together with the new web of packaging
material, to be in a fixed and initially non-moving position.
[0011] Therefore, a typical packaging apparatus also comprises a buffer unit arranged upstream
of the tube forming and sealing device and configured to buffer the web of packaging
material. Thus, prior to the need of splicing the new web of packaging material to
the web of packaging material in use, the quantity of the web of packaging material
present within the buffer unit (e.g. measured in meters and/or in seconds of the web
of packaging material present within the buffer unit) is increased such that during
the activation of the splicing unit, the portions of the web of packaging material
being arranged upstream of the buffer unit do not advance, while the portions of the
web of packaging material arranged downstream of the buffer unit advance as being
feed by the buffer unit.
[0012] The known buffer units comprise an infeed roller device, an outfeed roller device
and a first group of rollers and a second group of rollers. Thereby, the distance
between the second group of rollers and the first group of rollers is variable so
as to control the quantity of the web of packaging material being present within the
buffer unit. When there is the need to increase the quantity of the web of packaging
material, one increases the infeed speed with respect to the outfeed speed and increases
the relative distance between the first group of rollers and the second group of rollers,
while when there is the need to reduce the quantity of the web of packaging material
within the buffer unit, one reduces the infeed speed with respect to the outfeed speed
and reduces the relative distance between the first group of rollers and the second
group of rollers. During a normal operation condition, the relative distance between
the first group of rollers and the second group of rollers is kept substantially constant.
[0013] Even though such buffer units operate satisfyingly well, a desire is felt in the
sector to further improve the known packaging apparatuses.
DISCLOSURE OF INVENTION
[0014] It is therefore an object of the present invention to provide an improved buffer
unit for a packaging apparatus for producing packages formed from a web of packaging
material and being filled with a pourable product.
[0015] It is a further object of the present invention to provide an improved packaging
apparatus for producing packages formed from a web of packaging material and being
filled with a pourable product.
[0016] It is another object of the present invention to provide an improved method for producing
packages formed from a web of packaging material and being filled with a pourable
product.
[0017] According to the present invention, there is provided a buffer unit as claimed in
claim 1.
[0018] Further advantageous embodiments of the buffer unit according to the invention are
specified in the respective dependent claims.
[0019] Advantageously and according to the present invention, there is provided a packaging
apparatus according to claim 11.
[0020] Further advantageous embodiments of the packaging apparatus according to the invention
are specified in the claims being directly or indirectly dependent on claim 11.
[0021] Advantageously and according to the present invention, there is provided a method
according to claim 13.
[0022] Further advantageous embodiments of the method according to the invention are specified
in the claims being directly or indirectly dependent on claim 13.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] 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 having a buffer unit according
to the present invention, with parts removed for clarity;
Figure 2 is an enlarged schematic and perspective view of details of the packaging
apparatus of Figure 1, with parts removed for clarity;
Figure 3 is a schematic side view of further details of the packaging apparatus of
Figure 1 and with the buffer unit being in a first configuration, with parts removed
for clarity;
Figure 4 is a schematic side view of further details of the packaging apparatus of
Figure 1 and with the buffer unit being in a second configuration and having a first
load level, with parts removed for clarity; and
Figure 5 is a schematic side view of further details of the packaging apparatus of
Figure 1 and with the buffer unit being in the second configuration and having a second
load level, with parts removed for clarity.
BEST MODES FOR CARRYING OUT THE INVENTION
[0024] Number 1 indicates as a whole a packaging apparatus, in particular an automatic packaging
apparatus, for (continuously) producing packages 2 filled with a pourable product,
in particular a pourable food product, such as milk, fruit juice, wine, water, salt,
sugar, and similar. Packaging apparatus 1 is configured to produce packages 2 from
a web of packaging material 3, in particular by forming, filling and sealing the web
of packaging material 3.
[0025] In more detail, web of packaging material 3 may have a multilayer structure (not
shown) and may comprise 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 may define an inner face of package 2 eventually
contacting the pourable product.
[0026] Preferably, web of packaging material 3 may also comprise 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, web of packaging material 3 may 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.
[0027] According to the embodiment disclosed, web of packaging material 3 comprises a succession
of patterns, in particular each pattern being associated to one respective package
2 once the respective package 2 has been formed.
[0028] With particular reference to Figures 1 and 2, packaging apparatus 1 comprises at
least:
- a conveying device 4 configured to advance web of packaging material 3 along a web
advancement path P;
- a buffer unit 5 configured to buffer web of packaging material 3;
- a tube forming and sealing device 6 configured to form a tube 7 from the, in use,
advancing web of packaging material 3 and to longitudinally seal tube 7;
- a filling device 8 configured to fill tube 7 with the pourable product; and
- a package forming unit (not shown and known as such) configured to form, to transversally
seal and, preferably to transversally cut, tube 7, for forming packages 2.
[0029] Preferentially, operation of buffer unit 5 may be controlled in dependence of operation
of conveying device 4.
[0030] In more detail, tube forming and sealing device 6 may be arranged downstream of buffer
unit 5 along web advancement path P.
[0031] Preferentially, conveying device 4 may also be configured to advance tube 7 along
a tube advancement path Q. In more detail, conveying device 4 may be configured to
advance tube 7 and any intermediate of tube 7, in a manner known as such, along tube
advancement path Q. In particular, with the wording intermediates of tube 7 any configuration
of web of packaging material 3 is meant prior to obtaining the tube structure and
after folding of web of packaging material 3 by tube forming and sealing device 6
has started. In other words, the intermediates of tube 7 are a result of a gradual
folding of web of packaging material 3 so as to obtain tube 7, in particular by overlapping
lateral edges of web of packaging material 3 with one another.
[0032] Preferentially, packaging apparatus 1 may also comprise a control unit configured
to control operation of packaging apparatus 1.
[0033] Advantageously, packaging apparatus 1 may also comprise an isolation chamber (not
shown and known as such) having an inner environment, in particular a sterile inner
environment. In particular, the isolation chamber separates the inner environment
from an (hostile) outer environment.
[0034] Preferentially, the isolation chamber may have a vertical orientation.
[0035] Preferentially, tube forming and sealing device 6 may be at least partially arranged
within the isolation chamber and/or the inner environment and configured to form and
longitudinally seal tube 7 within inner environment.
[0036] According to some preferred non-limiting embodiments, packaging apparatus 2 may also
comprise a splicing unit (not shown and known as such) configured to splice a new
web of packaging material to web of packaging material 3 in use.
[0037] In particular, the splicing unit may be arranged upstream of buffer unit 5 along
web advancement path P.
[0038] Preferentially, packaging apparatus 1 may also comprise a magazine unit 9 having
at least a first support for carrying a reel 10 of web of packaging material 3. Even
more preferentially, magazine unit 9 may also comprise a second support for carrying
another reel 10 of web of packaging material 3.
[0039] More specifically, one of the first support and the second support may provide for
web of packaging material 3 in use and the other one of the first support and the
second support may provide for the new web of packaging material 3. In use, the roles
of the first support and the second support alternate. For example, at first the first
support carries reel 10 of web of packaging material 3 in use, while the second support
carries reel 10 of the new of packaging material 3. After the splicing, the second
support carries reel 10 of web of packaging material 3 in use, while the first support
carries another reel 10 of the new of packaging material 3.
[0040] According to some preferred non-limiting embodiments, packaging apparatus 1 may also
comprise a sterilizing unit (not shown and known as such) configured to sterilize,
in particular by means of chemical and/or physical sterilization, the, in use, advancing
web of packaging material 3. Preferentially, the sterilization station may be arranged
upstream of tube forming and sealing device 6 and downstream of buffer unit 5 along
web advancement path P.
[0041] Preferentially, the package forming unit may be configured to shape and transversally
seal and in particular cut, in use, tube 7 during advancement of tube 7 along at least
a portion of tube advancement path Q.
[0042] With particular reference to Figure 1, tube forming and sealing device 6 may comprise
a tube forming unit 13 at least partially, preferentially fully, arranged within the
isolation chamber, in particular within the inner environment, and configured to gradually
fold, in use, web of packaging material 3 into tube 7, in particular by (gradually)
overlapping the lateral edges of web of packaging material 3 with one another. Preferentially,
tube forming unit 13 may extend along a longitudinal axis, in particular having a
vertical orientation.
[0043] Preferentially, tube forming and sealing device 6 may also comprise a sealing unit
being at least partially arranged within the isolation chamber and/or the inner environment
and configured to longitudinally seal tube 7.
[0044] Furthermore, the sealing unit may comprise a sealing head (not shown) arranged within
the isolation chamber and being configured to transfer thermal energy to tube 7 for
longitudinally sealing tube 7. In particular, the sealing head can be of any type,
e.g. 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.
[0045] Preferentially, the sealing unit may also comprise a pressing assembly adapted to
exert a mechanical force on tube 7 so as to ensure the longitudinal sealing of tube
7.
[0046] With particular reference to Figure 1, filling device 8 may comprise a filling pipe
14 for directing the pourable product, in use, into tube 7. In particular, filling
pipe 14 may be 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 pourable food product, to
be packaged.
[0047] Preferentially, filling pipe 14 may, in use, be at least partially placed within
tube 7.
[0048] According to some preferred non-limiting embodiments, the package forming unit may
comprise a plurality of pairs of at least one respective operative assembly (known
as such and not shown) and at least one counter-operative assembly (known as such
and not shown); and
- a conveying unit (known as such and not shown) adapted to advance the respective operative
assemblies and the respective counter-operative assemblies of the pairs along respective
conveying paths.
[0049] In more detail, each operative assembly may be configured to cooperate, in use, with
the respective counter-operative assembly of the respective pair for forming one respective
package 2 from tube 7. In particular, each operative assembly and the respective counter-operative
assembly may be configured to shape, to transversally seal and, preferably also to
transversally cut, tube 7 for forming packages 2.
[0050] In further detail, each operative assembly and the respective counter-operative assembly
may be configured to cooperate with one another for forming a respective package 2
from tube 7 when advancing along a respective operative portion of the respective
conveying path. In particular, during advancement along the respective operative portion
each operative assembly and the respective counter-operative assembly may advance
parallel to and in the same direction as tube 7.
[0051] With particular reference to Figures 1 to 5, buffer unit 5 comprises:
- an infeed roller device 20 configured to feed web of packaging material 3 into buffer
unit 5; and
- an outfeed roller device 21 configured to direct web of packaging material 3 out of
buffer unit 5.
[0052] In particular, the portion of web of packaging material 3 being present within buffer
unit 5 may extend between infeed roller device 20 and outfeed roller device 21.
[0053] In particular, buffer unit 5 may lack any further roller devices interposed between
infeed roller device 20 and outfeed roller device 21 along web advancement path P.
In other words, there are no further roller devices interposed between infeed roller
device 20 and outfeed roller device 21 along web advancement path P.
[0054] Preferentially, web of packaging material 3 does not interact with any other kind
of roller devices, and respective rollers, in addition to infeed roller device 20
and outfeed roller device 21 when being within buffer unit 5.
[0055] Moreover, the loading of buffer unit 5 can be measured as the quantity of web of
packaging material 3 extending between infeed roller device 20 and outfeed roller
device 21. Thereby, the quantity of web of packaging material 3 within buffer unit
5 can be expressed in terms of meters and/or seconds. In more detail, when expressing
the quantity of web of packaging material 3 within in meters, one intends the meters
of web of packaging material 3 extending between infeed roller device 20 and outfeed
roller device 21, and along a longitudinal axis of web of packaging material 3. In
addition or alternatively, when expressing the quantity in seconds, one indicates
the quantity of web of packaging material 3 extending between infeed roller device
20 and outfeed roller device 21 and the time it is possible to feed web of packaging
material 3 out of buffering unit 5 without the need to introduce new web of packaging
material 3 into buffer unit 5.
[0056] Preferentially, buffer unit 5 is controllable in:
- an accumulation configuration, in which web of packaging material 3 is accumulated
within buffer unit 5, in particular between infeed roller device 20 and outfeed roller
device 21 (i.e. the quantity of web of packaging material 3 within buffer unit 5 is
increased);
- a buffering configuration, in which the quantity of web of packaging material 3 present
within buffer unit 5, in particular between infeed roller device 20 and outfeed roller
device 21, is kept substantially constant (i.e. the quantity of web of packaging material
3 within buffer unit 5 fluctuates around an average quantity); and
- a decumulation configuration, in which web of packaging material 3 present within
buffer unit 5, in particular between infeed roller device 20 and outfeed roller device
21, is decumulated (i.e. the quantity of web of packaging material 3 within buffer
unit 5 is reduced).
[0057] Preferentially, buffer unit 5 is controlled, in use, in particular by means of the
control unit, in the buffering configuration during a normal production of packaging
apparatus 1 for forming packages 2. When it becomes necessary (e.g. because one needs
to prepare for activation of the splicing unit) to buffer web of packaging material
3 within buffer unit 5, in particular between infeed roller device 20 and outfeed
roller device 21, buffer unit 5 is controlled, in use, in particular by means of the
control unit, in the accumulation configuration. Afterwards (e.g. after completion
of a splicing of web of packaging material 3 in use with the new web of packaging
material 3), buffer unit 5 is controlled, in use, in particular by means of the control
unit, in the decumulation configuration. Then, buffer unit 5 is controlled, in particular
by the control unit, in the buffering configuration again.
[0058] Moreover, buffer unit 5 also comprises an accumulation housing 22 having an accumulation
space 23 configured to randomly receive (see Figures 4 and 5) web of packaging material
3 while buffer unit 5 is controlled, in use, in the accumulation configuration.
[0059] In particular, accumulation housing 22 may delimit accumulation space 23.
[0060] More specifically and with particular reference to Figures 4 and 5, buffer unit 5,
in particular accumulation housing 22, may be configured such that while buffer unit
5 is controlled in the accumulation configuration, web of packaging material 3 being
present within buffer unit 5 randomly, in particular freely and randomly, falls into
accumulation housing 22, i.e. web of packaging material 3 being present within buffer
unit 5 may only interact with infeed roller device 20, outfeed roller device 21 and
accumulation housing 22 and web of packaging material 3 does not take a defined and
ordered position.
[0061] Additionally, in use, in dependence of the loading of buffer unit 5 (i.e. the quantity
of web of packaging material 3 present within accumulation housing 22 or, in other
words, the meters of web of packaging material 3 present within accumulation space
23) the shape of web of packaging material 3 continuously changes while buffer unit
5 is operated in the accumulation configuration. For example, web of packaging material
3 present within accumulation housing 22, in particular accumulation space 23, may
take a form as the one shown in Figures 4 and 5, but not necessarily. For example,
if web of packaging material 3 takes the form as the one shown in Figures 4 or 5,
such a specific configuration would typically persist only for a short time as new
web of packaging material 3 enters into accumulation space 23.
[0062] It should be noted that preferentially the term "randomly" indicates that the shape
of web of packaging material 3 is not determined and may vary.
[0063] In further detail, web of packaging material 3 randomly, in particular randomly and
freely, extends between infeed roller device 20 and outfeed roller device 21 while
buffer unit 5 is controlled in the accumulation configuration.
[0064] In particular, as buffer unit 5 lacks any further roller device and/or roller between
infeed roller device 20 and outfeed roller device 21, web of packaging material 3
present within buffer unit 5 is freely connected between infeed roller device 20 and
outfeed roller device 21.
[0065] Moreover, while buffer unit 5 is controlled in the accumulation configuration, the
quantity of web of packaging material 3 present within buffer unit 5 can be modified,
in particular until accumulation space 23 is fully occupied and/or a maximum load
is obtained.
[0066] In more detail and with particular reference to Figure 3, buffer unit 5 is configured
such that web of packaging material 3 is arranged in a free loop 24 within buffer
unit 5, in particular between infeed roller device 20 and outfeed roller device 21,
while buffer unit 5 is controlled in the buffering configuration.
[0067] In even more detail, buffer unit 5 is configured such that while, in use, buffer
unit 5 is controlled in the buffering configuration free loop 24 present within buffer
unit 5 fluctuates around an average shape, e.g. measured in meters and/or in dependence
of the position of an apex 25 of free loop 24.
[0068] It should be noted that free loop 24 may develop as there are no further elements
(such as, for example, rollers), which may define the shape of web of packaging material
3 extending within buffer unit 5, in particular between infeed roller device 20 and
outfeed roller device 21, and in particular also because of the acting gravitational
force.
[0069] Advantageously, buffer unit 5 may be configured such that while buffer unit 5 is
controlled in the decumulation configuration, the randomly, in particular the freely
and randomly, arranged web of packaging material 3 is decumulated out of accumulation
space 23, and in particular out of buffer unit 5. Preferentially, buffer unit 5 is
controlled back from the decumulation configuration to the buffering configuration
once web of packaging material 3 present within buffer unit 5 takes the form of a
free loop 24 again, and in particular having the desired quantity of web of packaging
material 3.
[0070] With particular reference to Figures 2 to 5, accumulation housing 22 may comprise
a main wall 26, a plurality of lateral delimiting walls 27 transversal, in particular
perpendicular, to main wall 26 and a main opening 28 through which web of packaging
material 3 enters into accumulation space 23.
[0071] In particular, main wall 26 may be opposite to main opening 28.
[0072] More specifically, main wall 26 may define a bottom wall of accumulation housing
22.
[0073] Preferentially, main opening 28 may be delimited by respective lateral delimiting
walls 27.
[0074] In particular, main opening 28 may be arranged at an upper portion of accumulation
housing 22.
[0075] In use, when buffer unit 5 is controlled in the accumulation configuration, web of
packaging material 3 has a shape of a free loop until web of packaging material 3
starts to contact main wall 26. Then, web of packaging material 3 becomes randomly
distributed within accumulation housing 22, in particular accumulation space 23.
[0076] With particular reference to Figures 1 to 5, infeed roller device 20 may comprise
a drive roller 32 and one or more counter rollers 33, in the specific case shown two,
in particular for interposing web of packaging material 3 between drive roller 32
and the one or more counter rollers 33.
[0077] Moreover, infeed roller device 20 may also comprise an actuator 34, in particular
a motor, even more particular an electrical motor, configured to actuate a rotation
of drive roller 32. In particular, actuator 34 may be configured to control an angular
speed of drive roller 32 such to at least partially control an infeed speed of web
of packaging material 3 into accumulation housing 22, in particular accumulation space
23.
[0078] Reverting again to Figures 1 to 5, outfeed roller device 21 may also comprise a main
roller 35 and one or more counter rollers 36, in the specific case shown two, in particular
so as to interpose, in use, web of packaging material 3 between main roller 35 and
the one or more counter rollers 36.
[0079] Preferentially, outfeed roller device 21 may also comprise a brake 37 configured
to decelerate main roller 35, in particular so as to control the tension of web of
packaging material 3, in particular downstream of outfeed roller device 21 along web
advancement path P.
[0080] In particular, web of packaging material 3 may freely extend between drive roller
32 and main roller 35.
[0081] According to some preferred non-limiting embodiments, buffer unit 5 and/or conveying
device 4 may be configured such that:
- an infeed speed of web of packaging material 3 into buffer unit 5 substantially corresponds
to an outfeed speed of web of packaging material 3 out of buffer unit 5, when buffer
unit 5 is controlled in the buffering configuration; and/or
- the infeed speed of web of packaging material 3 into buffer unit 5 is larger than
the outfeed speed of web of packaging material 3 out of buffer unit 5, when buffer
unit 5 is controlled in the accumulation configuration; and/or
- the infeed speed of web of packaging material 3 into buffer unit 5 is smaller than
the outfeed speed of web of packaging material 3, in particular this may include the
possibility of keeping the infeed speed of web of packaging material 3 at 0 m/s, out
of buffer unit 5, when buffer unit 5 is controlled in the decumulation configuration.
[0082] In more detail, infeed roller device 20, in particular drive roller 32, is configured
such to at least partially control the infeed speed of web of packaging material 3
into buffer unit 5 such that:
- the infeed speed is larger than the outfeed speed while the buffer unit 5 is, in use,
controlled in the accumulation configuration; and/or
- the infeed speed is smaller than the outfeed speed, in particular including also the
possibility of keeping the infeed speed at 0 m/s, while the buffer unit 5 is, in use,
controlled in the decumulation configuration; and/or
- the infeed speed substantially corresponds to the outfeed speed while the buffer unit
5 is, in use, controlled in the buffering configuration.
[0083] According to some preferred non-limiting embodiments, conveying device 4 may comprise
a roller 38 arranged upstream of infeed roller device 20 along web advancement path
P. In particular, roller 38 may be arranged such that web of packaging material 3
has an auxiliary free loop 39 between roller 38 and infeed roller device 20.
[0084] In use, packaging apparatus 1 forms packages 2 filled with the pourable product.
In particular, packaging apparatus 1 forms packages 2 from tube 7 formed from web
of packaging material 3, tube 7 being continuously filled with the pourable product.
[0085] In more detail, operation of packaging apparatus 1 (in other words, the formation
of packages 2) comprises at least the steps of:
- advancing web of packaging material 3 along web advancement path P, in particular
by conveying device 4;
- forming tube 7, during which web of packaging material 3 is formed into tube 7, in
particular by tube forming and sealing device 6, even more particular by tube forming
unit 13;
- longitudinally sealing tube 7, during which tube 7 is longitudinally sealed, in particular
by tube forming and sealing device 6, even more particular by the sealing unit;
- filling tube 7, during which the pourable product is filled into tube 7, in particular
by filling device 8, even more particular by filling pipe 14.
[0086] Preferentially, the formation of packages 2 also comprises a further step of advancing,
during which tube 7 is advanced, in particular by conveying device 4, along tube advancement
path Q.
[0087] According to some preferred non-limiting embodiments, the formation of packages 2
also comprises a step of forming, during which packages 2 are formed from tube 7,
in particular by shaping, transversally sealing and in particular transversally cutting
tube 7. Preferentially, during the step of forming, packages 2 are formed by operation
of the package forming unit.
[0088] Preferentially, operation of packaging apparatus 1 may also comprise the step of
sterilizing, during which web of packaging material 3 is sterilized by the sterilization
unit.
[0089] According to some preferred non-limiting embodiments, operation of packaging apparatus
1 may also comprise a step of splicing, during which a web of packaging material 3
in use is spliced with a new web of packaging material 3.
[0090] Operation of packaging apparatus 1 may also comprise a step of controlling during
which the buffer unit 5 is controlled in one of the accumulation configuration, the
buffering configuration and the decumulation configuration.
[0091] In more detail, a step of accumulating is executed while the buffer unit 5 is controlled
in the accumulation configuration and during which web of packaging material 3 is
randomly accumulated within buffer unit 5, in particular within accumulation space
23 of accumulation housing 22.
[0092] Moreover, a step of normal buffering is executed while the buffer unit 5 is controlled
in the buffering configuration and during which free loop 24 of web of packaging material
3) is maintained within buffer unit 5, in particular between inlet roller device 20
and outlet roller device 21.
[0093] Additionally, a decumulation step is executed when the buffer unit 5 is controlled
in the decumulation configuration and during which web of packaging material 3 is
decumulated from buffer unit 5, in particular from accumulation space 23 of accumulation
housing 22.
[0094] In even more detail, during the step of accumulating the infeed speed of web of packaging
material 3 into buffer unit 5 may be larger than the outfeed speed of web of packaging
material 3 out of buffer unit 5.
[0095] Moreover, during the step of decumulating, the infeed speed of web of packaging material
3 into buffer unit 5 may be smaller than the outfeed speed of web of packaging material
3 out of buffer unit 5. This may include the possibility of keeping the infeed speed
of web of packaging material 3 at least for some time at 0 m/s.
[0096] Additionally, during the step of normal buffering, the infeed speed of web of packaging
material 3 into buffer unit 5 may substantially correspond to the outfeed speed of
web of packaging material 3 out of buffer unit 5.
[0097] Preferentially, the step of accumulating may be executed prior to the step of splicing.
[0098] Moreover the step of decumulating may be executed during the step of splicing.
[0099] In further detail, the step of accumulating may be executed after the step of normal
buffering. After termination of the step of accumulating, the step of decumulating
is executed and then the step of normal buffering is executed again.
[0100] The advantages of buffer unit 5 and/or packaging apparatus 1 and the method according
to the present invention will be clear from the foregoing description.
[0101] In particular, buffer unit 5 comes along with a simple design. This because there
is neither a first group of rollers nor a second group of rollers as in the prior
art buffer units. Accordingly, one also avoids relying on means for varying the relative
distance between the first group of rollers and the second group of rollers.
[0102] A further advantage resides in that web of packaging material 3 when passing through
buffer unit 5 is not in contact with any roller besides the ones of infeed roller
device 20 and outfeed roller device 21. This also reduces the stresses acting on web
of packaging material 3.
[0103] Clearly, changes may be made to buffer unit 5 and/or packaging apparatus 1 and/or
the method as described herein without, however, departing from the scope of protection
as defined in the accompanying claims.
1. A buffer unit (5) for a packaging apparatus (1) for forming packages (2) from a web
of packaging material (3) and being filled with a pourable product;
the buffer unit (5) being configured to buffer the web of packaging material (3) and
comprises:
- an infeed roller device (20) configured to feed the web of packaging material (3)
into the buffer unit (5);
- an outfeed roller device (21) configured to direct the web of packaging material
(3) out of the buffer unit (5) ; and
- an accumulation housing (22) having an accumulation space (23) configured to randomly
receive the web of packaging material (3)
wherein the buffer unit (5) is controllable in an accumulation configuration, in which
the web of packaging material (3) is randomly accumulated within the buffer unit (5)
.
2. Buffer unit according to claim 1, and also being controllable in a buffering configuration;
wherein the buffer unit (5) is configured such that the web of packaging material
(3) is arranged in a free loop (24) between the infeed roller device (20) and the
outfeed roller device (21) while the buffer unit (5) is controlled in the buffering
configuration.
3. Buffer unit according to claim 1 or 2, wherein the buffer unit (5) is also controllable
in a decumulation configuration;
wherein the buffer unit (5) is configured such that while the buffer unit (5) is controlled
in the decumulation configuration the randomly arranged web of packaging material
(3) is decumulated out of the accumulation space (23) .
4. Buffer unit according to any one of the preceding claims, wherein the web of packaging
material (3) freely and randomly extends between the infeed roller device (20) and
the outfeed roller device (21) while the buffer unit (5) is controlled in the accumulation
configuration.
5. Buffer unit according to any one of the preceding claims, wherein the accumulation
housing (22) comprises a main wall (26), a plurality of lateral delimiting walls (27)
transversal to the main wall (26) and a main opening (28) through which the web of
packaging material (3) enters into the accumulation space (23).
6. Buffer unit according to claim 5, wherein the main wall (26) is opposite to the main
opening (28).
7. Buffer unit according to any one of the preceding claims, wherein the infeed roller
device (20) comprises a drive roller (32) and at least one counter roller (33).
8. Buffer unit according to any one of the preceding claims, wherein the outfeed roller
device (21) comprises a main roller (35) and at least one counter roller (36).
9. Buffer unit according to claim 7 and 8, wherein the web of packaging material (3)
freely extends between the drive roller (32) to the main roller (35).
10. Buffer unit according to any one of the preceding claims, wherein the infeed roller
device (20) is configured such to keep an infeed speed of the web of packaging material
(3) into the buffer unit (5) to be larger than an outfeed speed of the web of packaging
material (3) from the buffer unit (5) while the buffer unit (5) is, in use, controlled
in the accumulation configuration.
11. A packaging apparatus (1) for forming packages (2) from a web of packaging material
(3) and being filled with a pourable product;
the packaging apparatus (1) comprises:
- a conveying device (4) for advancing the web of packaging material (3) along a web
advancement path (P);
- a buffer unit (5) according to any one of the preceding claims;
- a tube forming and sealing device (6) configured to form and longitudinally seal
a tube (7) from the web of packaging material (3) and being arranged upstream of the
buffer unit (5) along the web advancement path (P);
- a filling device (8) configured to direct, in use, the pourable product into the
tube (7); and
- a package forming unit configured to at least form and to transversally seal the,
in use, advancing tube (7) for forming the packages (2).
12. Packaging apparatus according to claim 11, and further comprising a splicing unit
configured to splice a new web of packaging material (3) to the web of packaging material
(3) in use;
wherein the buffer unit (5) is configured to be controlled in the accumulation configuration
prior to an activation of the splicing unit.
13. Method for forming packages (2) from a web of packaging material (3) and being filled
with a pourable product comprising at least the steps of:
- advancing the web of packaging material (3) along a web advancement path (P);
- forming a tube (7) from the web of packaging material (3) ;
- longitudinally sealing the tube (7);
- filling the tube (7) with the pourable product; and
- accumulating the web of packaging material (3), during which a buffer unit (5) accumulates
the web of packaging material (3);
wherein the buffer unit (5) comprises:
- an infeed roller device (20) configured to feed the web of packaging material (3)
into the buffer unit (5);
- an outfeed roller device (21) configured to direct the web of packaging material
(3) out of the buffer unit (5); and
- an accumulation housing (22) having an accumulation space (23) configured to randomly
receive the web of packaging material (3);
wherein during the step of accumulating, the buffer unit (5) randomly accumulates
the web of packaging material (3) within the accumulation space (23).
14. Method according to claim 13, and further comprising a step of controlling the buffer
unit (5) in one of:
- an accumulation configuration for accumulating the web of packaging material (3)
within the buffer unit (5);
- a buffering configuration at which the buffer unit (5) keeps the quantity of the
web of packaging material (3) within the buffer unit (5) substantially constant; and
- a decumulation configuration during which the web of packaging material (3) present
within the buffer unit (5) is decumulated;
wherein the step of accumulating is executed while the buffer unit (5) is controlled
in the accumulation configuration and during which the web of packaging material (3)
is accumulated within the buffer unit (5);
wherein a step of normal buffering is executed when the buffer unit (5) is controlled
in the buffering configuration and during which a free loop (24) of the web of packaging
material (3) is maintained within the buffer unit (5); and
wherein a decumulation step is executed when the buffer unit (5) is controlled in
the decumulation configuration and during which the web of packaging material (3)
is decumulated from the buffer unit (5).
15. Method according to claim 13 or 14, and further comprising a step of splicing, during
which a web of packaging material (3) in use is spliced with a new web of packaging
material (3);
wherein the step of accumulating is executed prior to the step of splicing.