Application field
[0001] The present invention relates to a method for closing packages in a case packer and
a relative package closing station of a case packer.
[0002] The present invention finds a particular use in case packers intended to form packages
of an expositive type, containing pillow bags for salty snacks. By pillow bags is
meant, in the context of the present invention, bags with symmetric upper and lower
weldings made of a plastic film suitable to contain food products under protected
conditions. The pillow bags on which the case packer according to the present invention
is intended to operate are pillow bags containing salty snacks preferably having a
bulk density ranging between 0.02 and 0.1 Kg/liter. An example of such pillow bags,
which will be explicitly referred to herein below, is given by bags containing chips
or the like. By case packer is meant, in the context of the present invention, a machine
that is capable of forming a box, usually made of cardboard, intended to contain a
plurality of pillow bags.
Description of the prior art
[0003] The pillow bags containing salty snacks are usually cased at the manufacturing plant
in order to be able to be transported and subsequently sold. A type of boxes (or packages)
that is advantageously used, referred to as a display case or box, allows both containing
in an ordered manner the pillow bags for the transport thereof, and acting as a display
stand for the retail sale of the pillow bags. Usually, the packages of a displaying
type are made of a first portion comprising a support base and two opposite side walls
(between which two side openings are defined), and a second portion comprising a top
wall and two further opposite side walls that close the side openings of the first
packaging portion. By mutually coupling the two packaging portions, a closed box containing
the pillow bags is obtained. By removing the second portion, the top wall and two
side walls are removed, leaving the pillow bags contained in the lower portion and
at view for an immediate withdrawal and purchase. In order to be able to suitably
display the pillow bags, the side walls that are removed, i.e. those belonging to
the second portion, have to be the side walls intended to contact the front (or rear)
surface of the pillow bag, which usually carries the mark of the product, images of
the product contained in the bag, and the like.
[0004] It shall be apparent that, since the pillow bags are not able to lie in a vertical
position in the absence of an abutment or support, when the upper portion of the packaging
is removed, it may occur that one or more pillow bags tend to fall, exiting the packaging.
[0005] This peculiarity does not originate particular problems when the upper portion of
the packaging is removed to provide the pillow bags for the sale, since the sales
clerk more easily arranges the bags back to their proper position. However, this peculiarity
originates many problems during the formation of the packaging, particularly when
closing the packaging upper portion. In fact, during such operation (which takes place
with the pillow bags already positioned within the lower portion of the packaging)
possible overturns or falls of the pillow bags from the lower portion cause the inevitable
stop of the bagging line (the line forming the packaging around the pillow bags) in
order to reposition the bags.
[0006] Such interruptions, beside requiring the presence of an operator in charge of rearranging
the bags, cause a considerable slowing down in the bagging line, with consequent real
production of the packages containing pillow bags much below the nominal manufacturing
rate of the same line. Furthermore, the manufacturing rate of the bagging line can
be hardly assessed, due to the imponderability of the frequency with which the operator
has to intervene, thus making the proper dimensioning of the entire manufacturing
plant very difficult.
SUMMARY OF THE INVENTION
[0007] In this context, the technical task underlying the present invention is to propose
a method for closing packages in a case packer, and a package closing station of a
case packer, which solve the above-mentioned drawbacks of the prior art.
[0008] Particularly, it is the object of the present invention to provide a method for closing
packages in a case packer and a closing station of packages of a case packer capable
of ensuring a real manufacturing rate that is as near as possible to the nominal manufacturing
rate. A further object of the present invention is to propose a method for closing
packages in a case packer and a closing station of packages of a case packer which
do not need an operator in charge of supervising and interacting with the closing
station to ensure the efficiency thereof. The indicated technical task and the specified
objects are substantially achieved by a method for closing packages in a case packer
and a package closing station of a case packer comprising the technical characteristics
set forth in one or more of the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Further characteristics and advantages of the present invention will be more clearly
apparent from the illustrative, hance non-limiting, description of a preferred, but
not exclusive, embodiment of a method for closing packages in a case packer and a
package closing station of a case packer, as illustrated in the appended drawings,
in which:
- Figs. 1 to 4 schematically show a package closing station of a case packer according
to the present invention in different operative steps.
DETAILED DESCRIPTION
[0010] A package closing station of a case packer in accordance with the present invention
has been generally indicated by the number 1 in Fig. 1.
[0011] The station 1 comprises a transport line 2, which is arranged to support and transport
packages being formed, i.e. which are to be formed.
[0012] The transport line 2 extends along a direction X and comprises a conveyor belt 3,
which moves forward by pulses, i.e. it moves forward along the direction X by alternating
forward motions and pauses.
[0013] The packages are transported on the transport line 2 according to a single ordered
row, so that a transport line faces only one packaging being formed at a time at the
station 1.
[0014] The packages arrive only partially formed at the station 1. In particular, the transport
line supplies a first portion packaging 100 defined by a base surface 101 and two
first side walls 102 that are mutually opposite. Two opposite side openings open between
the first two side walls 102. Within the first packaging portion 100, pillow bags
200 are present, which are tidily arranged in rows and columns, so that the end rows
face the side openings, displaying the major surfaces of the same bags at the above-mentioned
openings (as shown in Fig. 1). Particularly, the rows of pillow bags are sorted parallel
to the advancement direction X of the transport line 2, while the columns are sorted
perpendicularly to the transport line 2.
[0015] It shall be noticed that the first packaging portion 100 substantially defines the
packaging portion acting as the display stand.
[0016] The station 1 further comprises supplying members 4 of a second packaging portion
103 in the form of a semi-finished piece. The supplying members 4 are active on the
transport line 2 between an active condition, in which they position the semi-finished
piece on the packaging, and a waiting position, in which they hold the semi-finished
piece 103 moving away from the packaging being formed. The movement between the active
condition and the waiting condition of the supplying members occurs through a vertical
translation, i.e. a translation perpendicular to the lying plane of the transport
line 2, so as to position the semi-finished piece 103 above the first packaging portion
100. In the preferred embodiment of the invention, the supplying members 4 comprise
a suctioning table that holds and handles the semi-finished piece 103. The supplying
members 4 further comprise actuators 6 intended to fold the semi-finished piece 103
along pre-weakening lines to obtain two opposite second side walls 104 (Fig. 2) of
the second packaging portion 103. Such two opposite second side walls 104 perform
the function of closing the side openings of the first packaging portion 100 to obtain
a completely closed packaging. The actuators 6 are actuated in the active condition
of the supplying members 4, i.e., during the positioning of the semi-finished piece
onto the first packaging portion. As illustrated in the appended figures, in the preferred
embodiment of the invention the actuators 6 comprise folding arms that are mutually
opposite and arranged at the portions of the semi-finished piece to be folded.
[0017] Advantageously, the station 1 comprises pneumatic members 7 that are active on the
transport line and switchable between an active condition, in which they direct a
compressed air flow towards the transport line so as to hit the pillow bags 200 at
the open side walls of the first packaging portion 100, and an inactive condition,
in which they are inactivated. The function of the pneumatic members 7 is to support
the pillow bags 200 during the positioning of the second packaging portion 103 onto
the first packaging portion 100, preventing the pillow bags (which are not able to
vertically lie autonomously) from being able to exit the overall dimensions of the
first packaging portion 100. Particularly, the pneumatic members 7 prevent the pillow
bags 200 from being able to overturn and fall from the side openings of the first
packaging portion 100.
[0018] To this aim, the pneumatic members 7 direct a compressed air flow through the side
openings of the first packaging portion 100 and against the pillow bags 200, so as
to push the latter ones towards the center of the packaging. In the preferred embodiment
of the invention, the pneumatic members 7 comprise two pluralities of diffusing nozzles
8 (only one of which is visible in the appended figures), each of which is arranged
at a side opening of the first packaging portion 100. The two pairs of pluralities
of diffusing nozzles 8 mutually face and are mutually opposite, so as to operate on
both openings of the first packaging portion 100 and the corresponding pillow bags.
The compressed air flow exiting the nozzles 8 is substantially perpendicular to the
extension direction X of the transport line 2 (as schematically shown in Fig. 1).
[0019] Preferably, the compressed air flow is dispensed at a pressure ranging between 2
bars and 8 bars, preferably about 4 bars. To this aim, the pneumatic members 7 comprise
a compressed air source (not shown) connected with the diffusing nozzles 8 in a
per se known manner. The diffusing nozzles 8 are arranged at a distance from the pillow
bags 200 ranging between 1 cm and 20 cm, preferably ranging between about 1 cm and
about 10 cm when they are operating and dispense compressed air.
[0020] The station 1 further comprises a pair of cross bars 9 (only one of which is visible
in Figs. 1 and 2), which are active at the transport line 2. The cross bars 9 mutually
face and are opposite, oriented parallel to the transport line 2 and arranged at the
side openings of the first packaging portion 100. The two cross bars 9 are movable
between a containment condition (shown in Fig. 1), in which they approach the transport
line 2 so as to position themselves at the open side walls of the first packaging
portion 100 and to hold the pillow bags 200 within the same packaging, and a moved-away
position (shown in Fig. 2), in which they move away from the transport line 2 and
do not hold the pillow bags 200. The function of the cross bars 9 is to support the
pillow bags 200 during the positioning of the first packaging portion 100 in the station
1 and during the positioning of the supplying members 4 of the semi-finished piece
103 that forms the second packaging portion.
[0021] When the supplying members 4 are switched to the active position, the cross bars
9 move away from the packaging in order not to mechanically interfere with the actuators
6 and to allow a proper formation of the packaging.
[0022] It shall be noticed that the action of the pneumatic members 7 is particularly efficient
exactly during the supplying members 4 activation and during the cross bars 9 moving
away, since in this step (which, operatively, has a duration ranging between 0.5 and
3 seconds) the pillow bags facing the openings of the first packaging portion 100
are not physically or mechanically abutted on by any supports.
[0023] In the preferred embodiment of the invention, the pneumatic members 7 are at least
partially integral to the cross bars 9. Particularly, the diffusing nozzles 8 are
positioned on the cross bars 9 and integral thereto. During the cross bars 9 handling
between the containment condition and the moved-away condition, the diffusing nozzles
8 dispense compressed air that holds the pillow bags in place within the first packaging
portion 100.
[0024] As the actuators 6 folds the semi-finished piece so as to define the second side
walls 104, the pillow bags 200 are abutted by such second side walls 104 and remain
in place.
[0025] In order to allow a complete closure of the packaging about the pillow bags 200,
the station 1 comprises a pair of pushing plates 10, each of which activates at the
transport line 2 to push respective lower edges 105 of the first packaging portion
100 against the second side walls of the second packaging portion 104. The pair of
pushing plates 10 is switchable between an active position, in which they compress
the lower edges 105 against the packaging being formed (Fig. 4) and a rest position,
in which they lie away from the packaging being formed (Fig. 1). The function of the
lower edges 105 is to abut against the second side walls and to stably and reliably
close the packaging (as shown in Fig. 4) The pushing plates 10 are preferably actuated
pneumatically, so as to use the same compressed air source that is used for the pneumatic
members 7. The pushing plates 10 are preferably heated or heatable to be able to activate
a film of glueing material present on the semi-finished piece 103 or on the first
packaging portion 100 and to stably join the second side walls 104 to the lower edges
105.
[0026] The method for closing packages in a case packer in accordance with the present invention
(already partially described above) provides for arranging the first packaging portion
100, containing pillow bags 200, so as to define the base surface 101, the two opposite
first side walls 102 and the two opposite side walls that are obtained between the
two first side walls 102.
[0027] The first packaging portion 100 is supplied to the closing station 1, where the second
packaging portion 103 is arranged, defining a top part and the two opposite second
side walls 104 intended to close the side openings of the first packaging portion
100. The two cross bars 9 are arranged near to the openings of the first portion to
hold the pillow bags 200 within the first packaging portion before positioning the
second packaging portion on the first packaging portion (Fig. 1).
[0028] The second packaging portion 103 is then lowered onto the first packaging portion
100 and the actuators 6 start bending the second side walls to close the side openings
of the first packaging portion 100. The two cross bars 9 are contextually moved away
from the packaging being formed to avoid interfering with the bending of the second
side walls 104.
[0029] At least during this step (illustrated in Fig. 2), a compressed air flow is directed
towards the two opposite side openings so as to mechanically hold the pillow bags)
(which are not mechanically abutted anymore) within the first packaging portion 100.
[0030] The two side walls are then folded onto the openings that display the pillow bags
(Fig. 3), at least partially abutting against the pillow bags and holding them in
place. In this step, the cross bars 9, and the diffusing nozzles 9 with them, are
completely moved away from the packaging in order not to interfere with the stroke
of the pushing plates 10, which start approaching the packaging to close the lower
edges 105 and to fold them onto the second side walls 104. As the second side walls
104 are completely folded onto the first packaging portion 100, the pushing plates
10 press the edges on such side walls 104 to completely close the displaying packaging.
In this step, the pushing plates 10 may be heated to activate an adhesive material
film and to glue the edges onto the side walls 104.
[0031] The so-closed packaging is advanced in order to reach a further station of the case
packer and a new first packaging portion 100 containing pillow bags 200 is supplied
to the station 1 to start again a new closing cycle.
[0032] The described station 1 and method achieve the proposed objects.
[0033] In fact, the compressed air flow allows keeping the pillow bags in place (which are
not capable, due to their peculiar shape, of autonomously supporting themselves in
place), allowing easily and quickly closing the packaging. It shall be further noticed
that no operator who constantly controls the station 1 and who locates the fallen
bags back to place is needed, since such event is prevented.
[0034] Again, the nominal manufacturing rate of the station 1, i.e., the number of packages
that may be closed per time unit, can be exactly assessed, allowing a proper dimensioning
of the entire case packer and of the entire manufacturing plant.
1. A method for closing packages in a case packer, comprising:
arranging a first packaging portion (100), containing pillow bags (200), so as to
define a base surface (101), two opposite first side walls (102) and two opposite
side openings between said first side walls (102);
feeding said first packaging portion (100) to a station (1) for closing the packaging;
arranging a second packaging portion (103) defining a top part and two opposite second
side walls (104) intended to close said opposite side openings;
positioning the second packaging portion (103) onto the first packaging portion (100)
and folding said two opposite second side walls (104) to close said opposite side
openings;
at least during the positioning of said second packaging portion (103) onto the first
portion, directing a compressed air flow towards the two opposite side openings so
as to hold the pillow bags (200) within the first packaging portion (100).
2. The method according to claim 1, comprising positioning two cross bars (9) near to
the opposite openings of the first packaging portion (100) to hold the pillow bags
(200) within the first packaging portion (100) before positioning the second packaging
portion (103) onto the first packaging portion (100).
3. The method according to claim 2, comprising moving said cross bars (9) away from the
packaging being formed during the folding of said second side walls (104) onto the
first packaging portion (100).
4. The method according to any of the preceding claims, wherein said compressed air flow
is dispensed at a pressure ranging between 2 bars and 8 bars, preferably about 4 bars.
5. The method according to any of the preceding claims, wherein said compressed air flow
is dispensed at a distance from said bags ranging between 1 and 20 cm, preferably
about 10 cm.
6. The method according to claim 2, wherein said compressed air flow is dispensed by
diffusing nozzles (8) located on each of said cross bars (9)
7. A package closing station of a case packer, comprising:
a transport line (2) arranged to support and transport first portions (100) of packages
being formed containing pillow bags (200) and open at least at two opposite side walls
(102);
supplying members (4) of a semi-finished piece (103), defining a second packaging
portion, active on said transport line (2) between an active condition, in which they
locate said semi-finished piece (103) on said first packaging portion (100) and close
said opposite side openings of the first packaging portion (100), and a waiting position
in which they hold said semi-finished piece (103) away from said first packaging portion
(100);
a pair of cross bars (9) active on said transport line (2) and movable between a containment
condition, in which they approach said transport line (2) so as to position themselves
at the open side walls of the first packaging portion (100), and a moved-away position,
in which they move away from said transport line (2);
pneumatic members (7) active on said transport line (2), switchable between an active
condition in which they direct a compressed air flow towards said transport line (2)
so as to hit said pillow bags (200) at said open side walls, and an inactive condition;
said pair of cross bars (9) being arranged to pass from the containment condition
to the moved-away condition when the supplying members (4) are switched to the active
condition, so that said cross bars (9) do not interfere with said semi-finished piece;
said pneumatic members (7) being arranged to be switched to the active condition at
least when the supplying members (4) are switched to the active condition.
8. The closing station according to claim 7, wherein said supplying members (4) comprise
actuators (6) arranged to fold said semi-finished piece (103) along pre-weakening
lines to obtain opposite second side walls (104); said actuators (6) being active
in the active condition of the supplying members (4).
9. The closing station according to claim 7 or 8, wherein said pneumatic members (7)
comprise at least a diffusing nozzle (8) located in the proximity of said transport
line (2); said diffusing nozzle (8) being configured to direct a compressed air flow
along a direction substantially perpendicular to said transport line (2).
10. The closing station according to claim 7, wherein said pneumatic members (7) are at
least partially integral to said cross bars (9) so as to move therewith.
11. The closing station according to any of the preceding claims, comprising at least
one pushing plate (10) active at said transport line (2) to push an edge (105) of
the first packaging portion against the second side walls of the second packaging
portion (103).