ITRE20090003A1 - '' METHOD AND PACKAGING DEVICE FOR FOOD PRODUCTS '' - Google Patents

Description

DESCRIPTION

of the Italian Patent for Industrial Invention entitled:

“METHOD AND PACKAGING DEVICE FOR PRODUCTS

FOOD "

The present invention relates to the packaging of food products, mainly of food products that perish, more or less quickly, when exposed to air.

More specifically, the present invention relates to food products with a complex shape, that is, which have folds, small recesses or cavities, in which the air can remain trapped despite the same being packaged in a protective atmosphere of inert gas.

An example of these food products is provided by fresh filled, rolled or folded pasta, such as ravioli, tortellini, cappelletti and the like.

As anticipated, the aforementioned food products are packaged in dosed quantities inside special sealed containers, where they are generally stored immersed in a protective atmosphere designed to prevent or at least contrast their deterioration.

According to a known packaging method, to which the invention refers in particular, it is known to package these products inside sealed bags that are formed with a flexible film of heat-sealable plastic material.

The realization of the bags provides that a flexible film strip is unwound from a reel and passed through a forming device comprising a vertical forming tube to which a shaped collar is associated.

By sliding in contact on said collar, the flexible film strip is forced to orient itself vertically and fold back on itself so as to take the form of a sleeve that wraps the forming tube.

The sliding of the flexible film belt is obtained by a pair of motorized tracks located downstream of the collar, which adhere to the flexible film by friction or by means of a suction system.

The forming device further comprises first sealing means which are adapted to join together the free vertical edges of the flexible film strip, so as to laterally close the sleeve, and second sealing means which are capable of transversely sealing the film strip. under the forming tube, so as to close the bottom of the sleeve creating an open envelope.

The products to be packaged are dosed with appropriate weighing means and subsequently released inside the forming tube, so that they are collected by gravity inside the open bag of flexible film formed at the lower end of the tube itself.

Subsequently, the second sealing means start again to seal the flexible film strip transversely above the collected products, hermetically sealing the bag in which they are contained.

The envelope thus filled and sealed is finally separated from the flexible film tape by means of suitable cutting means, and the cycle is repeated.

To preserve the product in a protective atmosphere, the inert gas is introduced into the bag, or more generally the container, before the final sealing.

In some cases, the introduction of the inert gas may be preceded by a deaeration phase of the product to be packaged, which is performed directly inside the bag or container, by means of air suction and consequent creation of a vacuum.

If deaeration is not performed, there is the possibility that a certain amount of air may remain in contact with the packaged products, especially if the latter have a complex shape with folds or cavities in which the air can remain trapped.

If, on the other hand, deaeration is performed, it generally takes a very long time to suck out all the air present inside the bag or container, to the detriment of productivity.

The object of the present invention is to solve the aforementioned drawbacks of the known art, by making available a method and a packaging device which allow to improve the deaeration of the packaged product, without decreasing productivity or at least without excessively reducing it.

A further purpose of the invention is to achieve the aforementioned objective in the context of a simple, rational and low-cost solution.

These purposes are achieved by the characteristics of the invention reported in the independent claims. The dependent claims outline preferred and / or particularly advantageous aspects of the invention.

In particular, a method for the packaging of food products is made available which includes the following steps:

place a dose of food products to be packaged inside a deaeration chamber,

hermetically close said deaeration chamber with said food products inside,

suck in the air contained within said deaeration chamber after it has been hermetically closed, and subsequently

open said deaeration chamber to let out the food products contained therein and transfer them inside a relative packaging container.

Thanks to this solution, inside the deaeration chamber it is effectively possible to create a much higher vacuum than that which can be obtained directly in the packaging container, especially in the case of a flexible film bag, thereby also being able to eliminate the any air trapped between the folds and cavities of the products.

According to a preferred aspect of the invention, the packaging method can comprise the further step of introducing inert gas into the deaeration chamber, when the same is still hermetically closed with the food products inside and after aspiration of the air.

The introduction of inert gas, typically a mixture of carbon dioxide (CO2) and molecular nitrogen (N2), creates a protective atmosphere that allows the product to be stored for longer.

To implement the method in question, a device is made available which comprises: a deaeration chamber which is hermetically closed by closing means which can be opened to allow the products to be packaged to enter and subsequently to allow them to be released into a container of packaging, e

means for sucking the air contained inside said deaeration chamber when it is hermetically closed with said food products inside.

Preferably, the device in question also includes means for introducing inert gas into the deaeration chamber, when the same is still hermetically closed with the food products inside and after the air has been aspirated.

Further features and advantages of the invention will become evident from reading the following description provided by way of non-limiting example, with the aid of the figures illustrated in the attached tables.

Figure 1 schematically shows a packaging machine according to the invention, sectioned according to a vertical plane that crosses the deaeration chamber.

Figure 2 is the partial section II-II of Figure 1.

Figure 3 schematically shows a packaging machine conforming to a different embodiment, also sectioned according to a vertical plane that crosses the deaeration chamber.

The machine in question is used for packaging bulk food products 100, mainly food products of complex shape such as filled, rolled or folded fresh pasta.

As illustrated in Figure 1, the packaging machine 1 comprises a cylindrical container 2, oriented with a vertical axis, which delimits inside itself a deaeration chamber 20 for the food products 100 to be packaged.

The upper and lower ends of the cylindrical container 2 are both open, so as to define respectively an inlet and an outlet for food products 100 in / from the deaeration chamber 20.

The cylindrical vessel 2 is associated with an upper shutter 3 and a lower shutter 4 which, through the interposition of appropriate sealing means, are designed to hermetically close the inlet and respectively the outlet of the deaeration chamber 20.

The upper shutter 3 is coupled to a double-acting pneumatic cylinder 30, which is able to move it between a closed position and an opening position of the entrance to the deaeration chamber 20.

Similarly, the lower shutter 4 is coupled to a respective double-acting pneumatic cylinder 40, which is able to move it between a closed position and an open position of the outlet of the deaeration chamber 20.

Obviously the shutters 3 and 4 could be replaced by any other shutter element suitable for the purpose, just as the relative pneumatic cylinders 30 and 40 could be replaced by other actuation means, for example by suitable mechanisms enslaved to electric motors.

The cylindrical container 2 is also provided with a suction mouth 21, which is connected to first pumping means (per se known and not illustrated) suitable for sucking the air from the deaeration chamber 20.

The cylindrical vessel 2 is also provided with an inlet port 22, which is connected with second pumping means (known per se and not illustrated) suitable for introducing inert gas into the deaeration chamber 20, typically a mixture of carbon dioxide and nitrogen.

The cylindrical vessel 2 is finally provided with a vacuum gauge 23 suitable for measuring the pressure which reigns in the deaeration chamber 20 instant by instant.

The packaging machine 1 also comprises dosing means (known per se and not illustrated) which, through a suitable weighing system, are able to cyclically release a predetermined quantity of food products 100 inside a loading hopper 5 placed above the cylindrical vessel 2.

The lower mouth of said loading hopper 5 is aligned with the inlet of the deaeration chamber 20, so as to be intercepted by the upper shutter 3 when the latter is in the closed position.

In the illustrated embodiment, the packaging machine 1 finally comprises a forming device, globally indicated with 6, for making envelopes intended for packaging food products 100.

The forming device 6 comprises a vertical forming tube 60, open at both ends, which is positioned below the cylindrical vessel 2 aligned with the outlet of the deaeration chamber 20.

Associated with the forming tube 60 is a collar 61 per se known, which is shaped in such a way as to force a strip 200 of flexible film which slides on it to orient itself vertically, and to fold on itself so as to embrace the forming tube 60 by wrapping it.

In practice, the flexible film tape 200 takes the form of a sleeve that wraps the forming tube 60 and which is able to slide vertically on it from top to bottom.

The flexible film is made of heat-sealable plastic material and unwinds from a reel, known per se and not illustrated, which is placed upstream of the collar 61.

As illustrated in Figure 2, the flexible film belt 200 is driven in sliding by a pair of motorized tracks 62, which are placed on diametrically opposite sides of the forming tube 60 downstream of the collar 61.

Said motorized tracks 62 adhere to the flexible film belt 200 by pressing it against the adjacent wall of the forming tube 60 or by means of a suction system, and are operated simultaneously at the same speed, so as to drag the flexible film belt 200 downwards. , consequently causing it to unwind from the reel and slide on the collar 61.

The forming device 6 comprises first sealing means suitable for joining together the free vertical edges of the flexible film strip 200 downstream of the collar 61, so as to laterally close the sleeve that said strip 200 forms around the forming tube. schematically comprise a vertical bar 63, which is associated with means suitable for heating it, and is provided with an approaching and distancing movement with respect to the forming tube 60, so as to press against the latter the free edges of the strip 200, welding them with each other in correspondence with an area of mutual overlap.

Finally, underneath the forming tube 60, second sealing means are provided, which are suitable for transversely sealing the strip 200 of flexible film for a portion of limited thickness, so as to close the bottom of the cylindrical sleeve and thus create a sort of 201 envelope open upwards.

Said second welding means schematically comprise two opposite bars 64, oriented horizontally and arranged at a certain distance under the forming tube 60, which are associated with means suitable for heating them, and are provided with a horizontal movement of reciprocal approaching and distancing, for clamp the flexible film sleeve in a vice.

The packaging machine 1 is finally completed by one or more straws 7 inserted inside the forming tube 60.

The lower end of said straw 7 flows into the envelope 201 of flexible film 200 in formation. The upper end of the straw 7 is instead connected with third pumping means (known per se and not illustrated) to diffuse in the bag forming inert gas, typically a mixture of carbon dioxide and nitrogen.

There is also the presence of additional straws that are closed at their lower end, but have exit holes obtained laterally along their longitudinal development.

In use, the metering means (not shown) cyclically dispense a dose of products to be packaged 100 into the loading hopper 5, so that each dose rests on the upper shutter 3 which closes the cylindrical container 2. When said dose is in the loading hopper 5, the upper shutter 3 is moved to the open position, causing the products 100 to fall by gravity into the deaeration chamber 20 whose bottom is closed by the lower shutter 4.

Subsequently, the upper shutter 3 is moved to hermetically close the deaeration chamber 20 with the product dose 100 inside, and to allow the release of another dose inside the hopper 5.

At this point, the first pumping means are put into operation which, through the suction mouth 21, suck the air present inside the deaeration chamber 20, creating a vacuum.

The vacuum in the deaeration chamber 20 must be sufficiently pushed to ensure the exit of most of the air present, possibly even that trapped in the folds or recesses of the products 100 having a complex shape.

The degree of vacuum created in the deaeration chamber 20 can be checked instant by instant through the vacuum gauge 23.

Once the air intake is complete, the second pumping means are activated which, through the inlet 22, introduce the inert gas mixture into the deaeration chamber 20, preferably until the initial atmospheric pressure is restored.

In the meantime, the tracks 62 advance the strip 200 of flexible film by an amount equal to the length of the envelope to be obtained, after which the sealing bars 63 stop and are put into action, which make the vertical closure of the strip 200. , and the sealing bars 64 which perform the lower horizontal sealing of the envelope being formed.

It should be noted that with a single welding operation, the bars 64 also seal the full envelope below, which will then be separated from the belt 200 by means of suitable cutting means.

At this point, the lower shutter 4 of the cylindrical container 2 is opened so that the products 100 fall by gravity into the forming tube 60, gathering in the flexible film envelope 201 that has formed at the lower end of the tube itself.

During this phase, the forming tube 60 and the flexible film bag 201 are both saturated with the inert gas that is delivered by the third pumping means through the straw 7, so that the products 100 always remain immersed in a protective atmosphere both during the transfer and when they are inside the 201 envelope.

The products 100 are thus collected inside the bag 201 under the sealing bars 64, while the lower shutter 4 of the deaeration chamber 20 closes behind them.

At this point, the sealing bars 64 start again to seal the flexible film strip 200 transversely, so as to hermetically seal the products 100 inside the envelope 201 and at the same time make a new empty envelope 201 available at the end. bottom of the forming tube 60.

The filled and sealed envelope 201 is finally separated from the flexible film strip 200 by means of suitable cutting means (known per se and not illustrated) and the cycle is repeated.

It should be noted that this system of deaeration of the products 100 outside the containers in which they are definitively packaged, can be applied not only to the case of packaging in bags 201 of flexible film but also to cases of packaging in trays, jars, glasses, etc ..

Figure 3 illustrates, for example, a packaging machine 1 'in accordance with the invention, in which the products 100 are packaged inside rigid preformed trays 300.

The packaging machine 1 'is constructively and functionally similar to that described above, from which it differs only in that it does not have the envelope forming device 6, which is replaced by a sliding surface 8 on which the pre-formed trays 300 are advanced in succession, typically a conveyor belt.

In use, each tray 300 is stopped under the outlet of the deaeration chamber 20, in order to receive the dose of products 100 that fall following the opening of the lower shutter 4.

Downstream of the cylindrical vessel 2, each tray 300 is then stopped in a second position where a straw 9 operates, which is connected with pumping means to diffuse inert gas into the tray 300, typically a mixture of carbon dioxide and nitrogen, and where moreover, means (not illustrated as they are known) operate for subsequently applying to the tray 300 a lid 301 adapted to hermetically seal it.

Obviously, a technician in the field will be able to make numerous changes of a technical-applicative nature to the machines and the packaging method described above, without departing from the scope of the invention as claimed below.

Claims (10)

CLAIMS 1. Method for packaging food products (100), characterized in that it comprises the steps of placing a dose of products (100) to be packaged inside a deaeration chamber (20), hermetically closing said deaeration chamber ( 20) with said products (100) inside, suck in the air contained inside said deaeration chamber (20) after it has been hermetically closed, and subsequently open the deaeration chamber (20), let out the products (100) contained therein and transfer them inside a relative packaging container (201, 300). 2. Method according to claim 1, characterized in that it comprises the step of introducing inert gas into the deaeration chamber (20) when it is hermetically closed with the products inside (100) and after aspiration of the 'air. 3. Method according to claim 1, characterized in that it comprises the step of hermetically sealing said packaging container (201, 300) after having filled it with the products to be packaged (100), and the step of introducing inert gas into said container of packaging (201, 300) before sealing it hermetically. 4. Method according to claim 1, characterized in that it comprises the step of releasing the products (100) leaving the deaeration chamber (20) into a vertical forming tube (60), on which a flexible film tape (200 ), which is sealed to form, at the lower end of said forming tube (60), an envelope (201) which receives the aforementioned products (100) and which defines their packaging container. 5. Device for packaging food products (100), characterized in that it comprises a deaeration chamber (20) which is hermetically closed by closure means (3, 4) which can be opened to allow the entry of a dose of products (100) to be packaged and the release of the same products (100) inside a packaging container (201, 300), and means (21) for sucking the air contained inside said deaeration chamber ( 20) when it is hermetically sealed with said products inside (100). 6. Device according to claim 5, characterized in that it comprises means (22) for introducing inert gas into the deaeration chamber (20) when it is hermetically closed with said products (100) inside and after air intake. 7. Device according to claim 5, characterized in that said deaeration chamber (20) is delimited by an external casing (2) equipped with an inlet and an outlet for the products (100) to be packaged, and that said means opening shutters comprise a first shutter (3) adapted to close said inlet and a second shutter (4) adapted to close said outlet, actuation means (30, 40) being provided to move said first and second shutter (3, 4) independently, to open and close respectively the inlet and outlet of the deaeration chamber (20). 8. Device according to claim 5, characterized in that it comprises means (64) for hermetically sealing the packaging container (201) in which the products (100) to be packaged have been released, and means (7, 9) for diffusing gas inert inside said packaging container (201) before it is sealed. 9. Device according to claim 5, characterized in that it comprises a vertical forming tube (60) whose upper end is adapted to receive the products (100) coming out of the deaeration chamber (20), means (61, 62) for wrapping around said forming tube (60) and making a flexible film tape (200) slide along it, and sealing means (63, 64) for sealing said flexible tape (200), so as to form at the lower end of said forming tube (60) an envelope (201) adapted to receive said products (100) and to define their packaging container. 10. Device according to claim 9, characterized by the fact that it includes means (7) for diffusing inert gas inside said forming tube (60) and inside said bag (201) of flexible film (200).