Production system for producing containers to be filled with a pourable food product, and relative method

Abstract

 There is disclosed a transfer unit (1) for transferring containers (2) to be filled with a pourable product along a path (P) extending about an axis (A); the unit (1) comprises: a first element (22) fixed with respect to said axis (A) and defining a first duct (23, 61) fluidically connectable with a source of an inert fluid (24); and a second element (25) rotatable about the axis (A), and comprising a plurality of nozzles (26a, 26b) fluidically connected with the first duct (23, 61) and adapted to inject the inert fluid inside the respective containers (2); the first element (22) and the second element (25) slidingly cooperate one against the other, so as to create a fluid-tight connection between the nozzles (26a, 26b) and the first duct (23, 61).

Description

[0001] The present invention relates to a production system and to a method for producing containers to be filled with a pourable food product.

[0002] In particular, the above said containers are intended to be filled, preferably according to an as aseptic as possible mode, with an especially sensitive pourable food.

[0003] Systems for manufacturing containers filled with a pourable product are known comprising substantially:

• a blowing station, in which a hot air flow is blown inside a plurality of preforms so as to form corresponding empty containers;
• a filling station, in which the above said empty containers are filled with the pourable product; and
• a capping station, in which a closing device is applied to each above said container.

[0004] In particular, each of the above said blowing, filling and capping stations comprises a carousel rotatable about a first axis.

[0005] The carousel of each of the above said stations comprises substantially:

• a plurality of transfer elements adapted to convey the containers (or the preforms) along a path having the shape of an arc of circumference, which extends about this first axis between an inlet station and an outlet station; and
• a plurality of operative units associated to respective transfer elements and adapted to perform a blowing, filing and capping operation on respective containers (or preforms) moving along the path having the shape of an arc of circumference.

[0006] The known filling systems also comprise a plurality of transfer conveyors, for example starwheels, rotatable about respective axes and adapted to transfer the containers (or the preforms) between the blowing, filling and capping stations.

[0007] More precisely, the transfer conveyors convey the containers along paths having the shape of an arc of circumference, for example 180 degrees long, which are tangent to one another.

[0008] Therefore, the transfer elements cooperate with respective containers along a first arc defining the above said path and are free from the respective containers along a second arc explementary to the first arc.

[0009] When the container is filled with an especially perishable pourable food product, the oxygen present in the head space of the containers needs to be ejected at the end of the filling step, so as to prolong as much as possible the time the product is aseptic and the organoleptic features of the pourable product are maintained once the opening devices are applied on the containers.

[0010] By the term "head space", there is intended the portion of the neck of the container above the level reached by the pourable product inside the container at the end of the filling operation.

[0011] In order to eject the oxygen, it is also known to inject an inert gas, for example nitrogen, inside the filled containers, so as to replace the oxygen in the head space of the containers with the nitrogen.

[0012] In order to maintain the pourable product aseptic and extend the organoleptic features of the product as much as possible, it is also known to inject nitrogen inside the containers before the filling step thereof, so as to reduce as much as possible the presence of oxygen inside the head space once the filling has been completed.

[0013] According to a known solution, the carousel of the filling station is provided with a plurality of valves borne by respective operative units and adapted to control the injection of nitrogen inside the containers, before filling the same.

[0014] In other words, while the containers are fed by the carousel of the filling station, they each first receive a nitrogen flow and then are filled with the pourable product.

[0015] According to another known solution, the injection of nitrogen takes place before the containers reach the filling station.

[0016] In greater detail, one of the transfer conveyors interposed between the blowing station and the filling station comprises:

• a first element fixed about the second axis and defining a duct connected with a non-rotating source of inert gas;
• a second element rotatable about the second axis integrally with the containers and comprising a plurality of injection nozzles for the inert gas; and
• a rotating distributor fluidically interposed between the fixed duct of the first element and the rotatable nozzles of the second element.

[0017] In particular, the nozzles are arranged above respective transfer elements of the carousel and therefore inject nitrogen inside the containers borne by the respective transfer elements.

[0018] The distributor must ensure the fluidic connection between the duct of the first fixed element and the rotatable nozzles and therefore comprises a plurality of pipings, bearings and sealing members.

[0019] The need is felt in the sector to inject the nitrogen inside the empty containers, thus reducing as much as possible the number of required components, in order to limit the production and/or maintenance costs.

[0020] Furthermore, the above distributor of solution of the known type connects the nozzles and the source of nitrogen, for each angular position of the carousel and thus the nozzles about the second axis.

[0021] However, the transfer elements convey the containers only along the first arc of circumference, which is shorter than 360 degrees.

[0022] Therefore, some of the transfer elements do not carry any container below the respective nozzles, when they move along the second arc of circumference.

[0023] There follows that the nitrogen exiting the nozzles moving along the second arc is dispersed in the environment, generating a problem both in terms of environmental pollution and of nitrogen waste.

[0024] Therefore, the need is felt in the sector to inject the nitrogen inside the empty containers without generating dispersion of nitrogen.

[0025] It is an object of the present invention to provide a transfer unit for containers to be filled with a pourable product, which allows to meet at least one of the above needs in a simple and cost-effective manner.

[0026] The above said object is achieved by the present invention, as it relates to a production system for producing containers to be filled with a pourable product, as defined by claim 1.

[0027] The present invention also relates to a method for producing containers to be filled with a pourable product, as defined in claim 10.

[0028] A preferred embodiment is hereinafter disclosed for a better understanding of the present invention, by way of non-limitative example and with reference to the accompanying drawings, in which:

• figure 1 is a top view of a transfer unit for containers to be filled with a pourable product made according to the dictates of the present invention;
• figure 2 is a perspective view of the transfer unit of figure 1;
• figure 3 is a section along line III-III of figure 1 of the transfer unit of figures 1 and 2;
• figure 4 is a further enlarged section of the transfer unit of figure 1 obtained along line IV-IV of figure 1, with parts removed for clarity;
• figures 5 and 6 are perspective views according to different viewing angles of a first component of the transfer unit of figures 1 to 4;
• figures 7 and 8 are perspective views according to different viewing angles of a second component of the transfer unit of figures 1 to 4;
• figure 9 is a sectional view of the first and second component of figures 5 to 8, with parts removed for clarity; and
• figure 10 diagrammatically shows a production system for containers comprising the transfer unit of figures 1 to 4.

[0029] With reference to figures 1 to 4, numeral 1 indicates a transfer unit for transferring empty containers 2 along a path P having the shape of an arc of circumference.

[0030] In detail, path P extends from an inlet station I for containers 2 up to an outlet station O for the containers.

[0031] Path P also extends about an axis A arranged in use vertically along an arc shorter than 360 degrees and equivalent to approximately 180 degrees in the case shown.

[0032] In particular, unit 1 is incorporated within a production system 3 (only diagrammatically shown in Figure 10) of containers 2 filled with a pourable product. In particular, the pourable product is a pourable food product which is especially perishable because it contains no preservatives, for example fruit juice.

[0033] System 3 substantially comprises (Figure 10):

• a blowing station 4 comprising, in turn, a plurality of blowing heads (not a shown) adapted to blow hot air inside respective preforms (not shown) so as to form corresponding empty containers 2;
• a filling station 5 comprising, in turn, a carousel 6 (only diagrammatically shown in figure 10) adapted to convey empty containers 2 along a path Q having the shape of an arc of circumference about an axis B, vertical in use, and a plurality of filling valves (not shown) adapted to fill empty containers 2 with the pourable product; and
• a capping station 7 comprising, in turn, a carousel 8 (only diagrammatically shown in figure 9) adapted to convey filled containers 2 along a path R having the shape of an arc of circumference about an axis D, vertical in use, and a plurality of capping heads (not shown) adapted to apply respective closing devices on corresponding containers 2.

[0034] System 3 also comprises, proceeding from blowing station 4 to filling station 5:

• a conveyor 9 fed by blowing station 4 with empty containers 2 and feeding station I of unit 1;
• unit 1; and
• a conveyor 10 fed by unit 1 at station O and feeding, in turn, filling station 5.

[0035] In particular, conveyors 9, 10 feed empty containers 2 along respective paths S, T having the shape of an arc of circumference and tangent to path P respectively at stations I, O.

[0036] System 3 also comprises:

• a conveyor 11 interposed between filling station 5 and capping station 7; and
• a conveyor 12 arranged downstream of capping station 7.

[0037] In detail, conveyor 11 conveys containers 2 along a path U having the shape of an arc of circumference tangent to paths Q, R.

[0038] System 3 is also adapted to inject an inert fluid, gaseous nitrogen in the case shown, inside empty containers 2 so as to reduce the concentration of oxygen in the head space of containers 2 as much as possible. By the term "head space", in the present description there is intended the space defined inside the neck portion 19 (visible in figure 2) of containers 2 between the surface of the pourable product and the relative closing devices, once the latter have been applied on containers 2.

[0039] Indeed, in particular for perishable pourable products which do not contain preservative, the presence of oxygen could give rise to the risk of the organoleptic features deteriorating and thus of reducing the preservation of the pourable product in aseptic conditions.

[0040] System 3 also comprises (Figure 10):

• a tunnel 14 fixed with respect to conveyor 10, overlapped at least partially to path T and adapted to inject nitrogen inside containers 2 fed along path T; and
• a tunnel 15 fixed with respect to conveyor 11, overlapped at least partially to path U and adapted to inject nitrogen inside containers 2 fed along path U.

[0041] Unit 1 comprises (figures 2 and 3):

• a stator 20 fixed with respect to axis A;
• a carousel 21 rotatable with respect to stator 20 about an axis A and comprising, at a peripheral edge thereof, a plurality of transfer elements 30 angularly equally spaced about axis A;
• a manifold 22 fixed with respect to axis A and defining a duct 23 fluidically connected to a source 24 (diagrammatically shown in figure 4) for gaseous nitrogen arranged externally to unit 1 by means of a fitting 18;
• a wheel 25 connected to carousel 21 so as to result rotatable integrally to carousel 21 about axis A.

[0042] Each transfer element 30 is adapted to withdraw relative empty container 2 at station I and convey it along path P and release it at station O.

[0043] In the case shown, each transfer element 30 comprises a pair of jaws 17 (figure 2) elastically loaded towards a first position and openable in a second position upon the action of the neck portion 19 of respective empty container 2.

[0044] Wheel 25 is interposed axially between manifold 22 and carousel 21.

[0045] Wheel 25 comprises in particular:

• a central body 32 (Figure 5); and
• a plurality of injection nozzles 26a, 26b fluidically connected with duct 23 and adapted to inject nitrogen inside respective empty containers 2.

[0046] Nozzles 26a, 26b are angularly spaced about axis A and are associated to respective transfer elements 30.

[0047] In particular, each nozzle 26a, 26b comprises essentially:

• a nitrogen feeding duct 27 arranged radially to axis A and projecting from central body 32; and
• an end portion 28 projecting from each duct 27 downwards.

[0048] Each end portion 28 also defines an injection mouth 29 arranged above a relative transfer element 30.

[0049] Advantageously, manifold 22 and wheel 25 slidingly cooperate one on the other so as to create a fluid-tight connection between duct 23 and nozzles 26a.

[0050] With reference to figures 7 and 8, manifold 22 comprises:

• a top face 51 having a pair of axially blind grooves 52 radially open on the opposite side of axis A;
• a bottom face 53 axially opposite to face 51;
• a side surface 49 extending between faces 51, 53; and
• an axial through-groove 54, extending radially from axis A so as to interrupt surface 49.

[0051] Grooves 52 are radially interrupted at a distance from axis A.

[0052] Groove 54 is radially open on the opposite side to axis A.

[0053] Duct 23 comprises an opening 55 defined by face 51 and opening 56, opposite to opening 55, defined by face 53.

[0054] Duct 23 extends along an axis C and comprises, proceeding from opening 55 to opening 56 (Figure 9):

• a cylindrical segment 57 fluidically connected with source 24;
• a frustoconical segment 58 tapered towards face 53;
• a cylindrical segment 59; and
• a cylindrical segment 60 having a greater diameter than the diameter of segment 59 and smaller than the diameter of segment 57.

[0055] Axis C is parallel and offset with respect to axis A.

[0056] Face 53 of manifold 22 defines a groove 61 configured as an arc of circumference about axis A and within which opening 56 faces.

[0057] Groove 61 is radially spaced from axis A and from surface 49 of manifold 22 and axis C passes therethrough.

[0058] Groove 61 is open axially on the opposite side of face 51.

[0059] Groove 61 extends along an arc substantially equivalent to the angular extension of path P about axis A and, in the case shown, equivalent to about 180 degrees.

[0060] Groove 61 is adapted to collect nitrogen from duct 23 and provide it to nozzles 26a moving along path P.

[0061] With reference to figures 5 and 6, wheel 25 substantially comprises:

• a head surface 70, adapted to slide on face 53 of manifold 22;
• a flange 71 axially opposite to surface 70 and fixed to carousel 21; and
• a ridge 72 axially interposed between surface 70 and flange 71, and radially projecting from the opposite side of axis A with respect to flange 71 and surface 70.

[0062] Wheel 25 defines a plurality of ducts 75 angularly equally spaced with respect to axis A and each comprising:

• an axial opening 76 defined by surface 70;
• a radial opening 77, opposite to opening 76, fluidically connected to a relative duct 27.

[0063] Each duct 75 also comprises, proceeding from opening 76 to opening 77 (figure 6):

• an axial segment 78; and
• a radial segment 79 coupled with duct 27 of relative nozzle 26a, 26b.

[0064] Openings 76 and groove 61 are at the same distance from axis A.

[0065] Opening 76 of each duct 75 is arranged at groove 61, when relative nozzle 26a travels along path P, i.e. moves between stations I, O.

[0066] In this condition, relative nozzle 26a is above empty container 2 transferred by relative transfer element 30 and injects nitrogen inside container 2.

[0067] Differently, opening 76 of each duct 75 is angularly offset from groove 61, when relative nozzle 26b moves from station O to station I, i.e. when corresponding transfer element 30 has released container 2.

[0068] In this condition, relative nozzle 26b is not fed with nitrogen and prevents nitrogen from being dispersed in the environment.

[0069] Unit 1 also comprises pressure means 80 adapted to press manifold 22 against wheel 25 and ensure that the nitrogen is entrapped between groove 61 and ducts 75 facing groove 61.

[0070] In greater detail, pressure means 80 comprise a spring 81 interposed between a fixed abutting element 82 and face 51 of manifold 22.

[0071] Spring 81 is, in the case shown, a helical spring having axis A.

[0072] Unit 1 finally comprises an antirotation structure 90 fixed to the ground. Abutting element 82 and the parts of unit 1, which are stationary with respect to axis A, are fixed to antirotation structure 90.

[0073] In particular, structure 90 is constrained to grooves 52 of manifold 22 (figure 4), so as to make manifold 22 fixed with respect to axis A.

[0074] The operation of production system 3 is shown with reference to a single empty container 2 to be filled with the poruable food product, and to corresponding nozzle 26a and transfer element 30.

[0075] In greater detail, a blowing head of blowing station 4 forms container 2 from a preform.

[0076] Subsequently, empty container 2 is fed by conveyor 9 along path S, is fed to unit 1 along path P tangent to path S and is fed by conveyor 10 along path T tangent to path P up to filling station 5.

[0077] Jaws 17 of transfer element 30 are arranged in the first position at station I of path P so as to withdraw empty container 2 from conveyor 9, are displaced from neck portion 19 to the second position in which they convey empty container 2 along path P, and are displaced back to the first position at station O of path P so as to provide conveyor 10 with empty container 2.

[0078] Nitrogen flows from source 24 to duct 23 and from the latter to groove 61.

[0079] Groove 61 faces segments 78 of ducts 75 which feed nozzles 26a nozzles along path P between stations I, O.

[0080] Thereby, nozzles 26a fed along path P are fed with nitrogen.

[0081] While empty container 2 moves along path P, it is maintained by transfer element 30 below corresponding nozzle 26a and thus receives a flow of nitrogen which determines the ejection of oxygen from the internal volume of empty container 2.

[0082] Differently, groove 61 is angularly offset with respect to axis A from segments 78 of ducts 75 in communication with nozzles 26b moving between stations O, I.

[0083] Thereby, nozzles 26b moving between station O and station I are not fed with nitrogen.

[0084] The action of spring 81 on face 51 pushes manifold 22 against wheel 25 and makes the connection between groove 61 and ducts 75 associated to nozzles 26a fluid-tight.

[0085] Once empty container 2 reaches station O, it is withdrawn by conveyor 10 and fed along path T and below tunnel 14.

[0086] Tunnel 14 performs a further nitrogen injection operation inside container 2 to be filled.

[0087] Subsequently, conveyor 10 transfers container 2 to filling station 5. Carousel 6 of filling station 5 conveys containers 2 along path Q. One of the filling valves fills container 2 moving along path Q with pourable product.

[0088] Conveyor 11 withdraws container 2 filled with the pourable product and conveys it along path U below tunnel 15.

[0089] Tunnel 15 injects nitrogen inside the head space defined by neck portion 19 of filled container 2. Oxygen present inside the head space is thus replaced by nitrogen.

[0090] Subsequently, carousel 8 of capping station 7 withdraws container 2 from conveyor 11 and feeds it along path R. One of the capping heads of capping station 7 applies the closing device on container 2.

[0091] Finally, filled container 2 is transferred to conveyor 12 and thus moves away from system 3.

[0092] From an analysis of the features of unit 1 and of the injection method according to the present invention, the advantages it allows to obtain are apparent.

[0093] In particular, manifold 22 fixed with respect to axis A and wheel 25 rotatable about axis A slide one against the other, so as to create a fluid-tight connection between groove 61 connected to source 24 and feeding ducts 75 of nozzles 26a.

[0094] Therefore, manifold 22 delivers, by means of groove 61, nitrogen to ducts 75 connected to nozzles 26a.

[0095] There follows that, differently from the know solutions disclosed in the introduction of the present description, unit 1 allows to inject nitrogen inside empty containers 2 to be filled without requiring the presence of a further rotating distributor between fixed manifold 22 and wheel 25.

[0096] Accordingly, unit 1 does not require the presence of pipings, bearings and sealing members associated to the further rotating distributor, thus resulting more cost-effective and simple both to produce and to maintain.

[0097] Furthermore, groove 61 is fluidically connected only with ducts 75 which feed nozzles 26a moving along path P.

[0098] Therefore, nitrogen is fed only to nozzles 26a and injected from the latter inside empty containers 2 moving along path P.

[0099] Differently, nozzles 26b moving between station O and station I, i.e along an arc explementary to path P, are not fed with nitrogen.

[0100] Thereby, unit 1 feeds with nitrogen only nozzles 26a arranged above respective containers 2 moving along path P.

[0101] Nozzles 26b, under which there is no empty container 2, are thus prevented from dispersing nitrogen in the environment.

[0102] Finally, it is apparent that modifications and variants not departing from the scope of protection of the claims may be made to production system 3 and to the method disclosed herein.

[0103] In particular, element 22 could have other forms than those shown in the present application.

[0104] For example, element 22 could not have groove 54 and have a plurality of ducts 23.

Claims

1. A production system (3) for producing containers (2) to be filled with a pourable food product, comprising:

- a transfer unit (1) for transferring empty containers (2) along a path (P) extending about an axis (A); said path (P) extending between an inlet station (I) and an outlet station (O) of said containers (2); and

- a filling station (5) adapted to fill said containers (2) with said pourable product;

said unit (1) being arranged upstream of said filling station (5) and adapted to transfer, in use, said empty containers (2) to be filled with said pourable food product to said filling station (5);
said unit (1) comprising:

- a first element (22) fixed with respect to said axis (A) and defining a first duct (23, 61) fluidically connectable with a source of an inert fluid (24); and

- a second element (25) rotatable about said axis (A), and comprising a plurality of first and second nozzles (26a, 26b) fluidically connected with said first duct (23, 61) and adapted to inject said inert fluid inside said respective empty containers (2);

characterised in that said first element (22) and said second element (25) slidingly cooperate one against the other, so as to create a fluid-tight connection between at least said first nozzles (26a) and said first duct (23, 61).

2. The production system according to claim 1, characterised in that:

- said first duct (23, 61) comprises a first annular portion (61) extending along an arc about said axis (A) and adapted to collect said inert fluid; and

- said second element (25) comprises at least one second duct (75) fluidically connected with said first nozzles (26a) and with said first portion (61) of said first duct (22).

3. The production system according to claim 2, characterised in that said first duct (23, 61) comprises a second axial portion (23) fluidically connectable, at its first end, to said source (24) and fluidically connected, at a second end opposite to said first end, with said first portion (61).

4. The production system according to claim 2 or 3, characterised in that said second element (25) comprises a plurality of said second ducts (75) fluidically connected with respective said first and second nozzles (26a, 26b) and angularly spaced about said axis (A);
said first portion (61) of said first duct (23, 61) being fluidically connected only with said second ducts (75) associated to relative said first nozzles (26a) which are fed along said path (P) from said inlet station (I) to said outlet station (O);
said first portion (61) of said first duct (23, 61) being fluidically insulated from said second ducts (75) associated to relative said second nozzles (26b) which are fed along said path (P) from said outlet station (O) to said inlet station (I).

5. The production system according to claim 4, characterised in that said second duct (75) comprises:

- a third portion (78) parallel to said axis (A); and

- a fourth portion (79) radial to said axis (A);
said third portion (78) of each said second duct (75) being interposed between said first portion (61) and said fourth portion (79) only when each said duct (75) feeds said inlet (I)and outlet stations (O).

6. The production system according to any of the preceding claims, characterised by comprising pressure means (80) adapted to press at least one (22) of said first and second element (22, 25) against the other (25) of said first and second element (22, 25).

7. The production system according to claim 6, characterised in that said pressure means (80) comprise elastic means (81) adapted to elastically load one (22) of said first and second element (22, 25) against the other (25) of said first and second element (22, 25).

8. The production system according to claim 7, characterised in that said elastic means (81) are interposed between said first element (22) and a fixed structure (90) of said unit (1).

9. The production system according to any of the preceding claims, characterised by comprising a carousel (21) rotatable about said axis (A) integrally with said second element (25) and comprising a plurality of transfer elements (30) adapted to transfer respective containers (2) along said path (P) between said inlet station (I) and said outlet station (O);
said transfer elements (30) being arranged, in use, below respective said first and second nozzles (26a, 26b).

10. A method for producing containers (2) to be filled with a pourable product, comprising the steps of:

a) transferring empty containers (2) along a path (P) extending about an axis (A) to a filling station (5); and

b) filling said empty containers (2) with said pourable product at said filling station (5);
said step a) comprising the steps of:

c) fluidically connecting a source (24) of said inert fluid with a first duct (23, 61) defined by a first element (22) fixed with respect to said axis (A);

d) fluidically connecting a plurality of second ducts (75) borne by a second element (25) rotatable about said axis (A) with said first duct (23, 61) and with respective first nozzles (26a); and

e) injecting said inert fluid inside respective said empty containers (2) by means of said first nozzles (26a);
characterised by comprising the step f) of sliding one against the other said first and second element (22, 25) so as to create a fluid tight connection between said first and second ducts (23, 61; 75).

11. The method according to claim 10, characterised in that said step f) comprises the steps of:

g) fluidically connecting said first duct (23, 61) and only said second ducts (75) associated to said first nozzles (26a) fed along said path (P); and

h) preventing the fluidic connection between said first duct (23, 61) and the further said second ducts (75) associated to second nozzles (26b) moving between said outlet station (O) and said inlet station (I).

12. The method according to claim 11, characterised in that said step g) comprises the steps of:

i) collecting said inert fluid inside a chamber (61) defined by said first duct (23, 61) and extending like an arc about said axis (A); and

j) fluidically connecting said chamber (61) with only said second ducts (75) associated to first said nozzles (26a).

13. The method according to any of claims 11 or 12, characterised by comprising the step k) of pressing said first and second element (22, 25) against one another.

Drawing