GAS FEEDER FOR A PACKAGING MACHINE AND SYSTEM FOR MANUFACTURING PACKAGES AND METHOD USING SAID SYSTEM

Abstract

 A gas feeder for a packaging machine comprises a gas source and a gas accumulator. The gas source is configured to feed a packaging gas to the gas accumulator. The gas accumulator comprises a portion of a conduit extending for a length from an inlet to an outlet along a path and configured to guide the packaging gas along the path. The inlet is coupled to the gas source to receive the packaging gas. The outlet is configured to be coupled to a workstation of a packaging machine to feed the packaging gas to the workstation. The portion presents a maximum and a minimum flux cross-sectional area respectively at a first and at a second cross-section. The maximum flux cross-sectional area is greater than or equal to the minimum flux cross-sectional area. A ratio of the length to a square root of the maximum flux cross-sectional area is greater than 100.

Description

BACKGROUND

[0001] The present disclosure is in the technical field of packaging machines. More particularly, the present disclosure is directed to a gas feeder for a packaging machine and to a system and method for manufacturing modified atmosphere packages comprising such gas feeder.

[0002] Gas feeders for manufacturing modified atmosphere packages are known in the art. The known systems comprise a packaging gas source and an accumulator tank in fluid communication to each other. The accumulator tank is configured to receive the packaging gas from the gas source and feed it to a workstation of a packaging machine. For example, the workstation of the packaging machine can be a sealing station which receive the packaging gas and inject it inside a package during the packaging process. The tank of the art is configured to support brief periods of time when the packaging gas is drawn into the sealing station at very high flow rate without needing to achieve that very high flow rate at the gas source. Therefore, the accumulation tank allows the gas source to feed gas to the tank continuously at a flow rate which is lower than the flow rate required by the sealing station of the packaging machine.

[0003] In detail, the known accumulators present an accumulation volume, which extends from an inlet to an outlet for a length and have a constant cross-sectional area. The ratio of the length of the accumulation volume of the known tanks to the square root of the cross-sectional area is around 4. The known accumulators favor a high level of mixing as the fed gas enters the accumulator. This leads to problems when there is a change in the gas composition at the gas source level. Indeed, if the composition of the gas at the gas source level changes, this change is rapidly transferred to the tank and all the gas herein accumulated is affected. Therefore, when the change in the composition causes the already accumulated gas to be no longer suitable for the packaging process, it is needed to discard all the accumulated gas. This means that a number of packages will be manufactured with not-suitable gas and therefore discarded.

[0004] Moreover, since the known types of tanks have a large accumulation volume, it is necessary to wait a considerable amount of time before the accumulated gas return to have the composition suitable for the packaging process.

[0005] Therefore, there is a need for a gas feeder for a packaging machine which is able to solve the drawbacks and/or limitations of the above prior art. There is a need for a system of manufacturing modified atmosphere packages and a method using said system which can solve the drawbacks and/or limitations of the prior art.

[0006] There is a need to provide a gas feeder for a packaging machine which can improve the efficiency of a packaging machine and/or of the packaging process. A gas feeder which can reduce the number of rejected packages in the packaging process is desired.

SUMMARY

[0007] This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[0008] In a 1st aspect, a gas feeder for packaging machine comprises a gas source and a gas accumulator in fluid communication with each other, the gas source being configured to feed a packaging gas to the gas accumulator, the gas accumulator comprising a portion of a conduit extending for a length from an inlet to an outlet along a path, wherein:

• the portion is configured to guide the packaging gas along the path,
• the portion presents a maximum flux cross-sectional area at a first cross-section and a minimum flux cross-sectional area at a second cross-section, the maximum flux cross-sectional area being greater than or equal to the minimum flux cross-sectional area,
• the inlet is coupled to the gas source to receive the packaging gas,
• the outlet is configured to be coupled to a workstation of a packaging machine to feed the packaging gas to the workstation,
• a ratio of the length to a square root of the maximum flux cross-sectional area is greater than 100.

[0009] In a 2nd aspect in accordance with the preceding aspect, a percentage ratio of the maximum flux cross-sectional area to the minimum flux cross-sectional area is less than or equal to 300%, preferably less than or equal to 250%, more preferably less than or equal to 200%, again more preferably equal to 100%.

[0010] In a 3rd aspect in accordance with any one of the preceding aspects, the first cross-section and second cross-section are circular or elliptical.

[0011] In a 4th aspect in accordance with any one of the preceding aspects, the length of the portion is greater than or equal to 5 meters, preferably greater than or equal to 10 meters, more preferably greater than or equal to 20 meters, even more preferably greater than or equal to 30 meters.

[0012] In a 5th aspect in accordance with any one of the preceding aspects, the ratio of the length to the square root of the maximum flux cross-sectional area is greater than 500, preferably greater than 1000, more preferably greater than 1500, even more preferably greater than 2000.

[0013] In a 6th aspect in accordance with any one of the preceding aspects, the path is a rectilinear path.

[0014] In a 7th aspect in accordance with any one of the preceding aspects, the path is a non-rectilinear path.

[0015] In an 8th aspect in accordance with the preceding aspect, the path is a helix path.

[0016] In a 9th aspect in accordance with either the 7th aspect or the 8th aspect, the path is around a direction of transfer, wherein the direction of transfer is defined by a direction connecting the inlet and the outlet.

[0017] In a 10th aspect in accordance with any one of the preceding aspects, the gas source comprises a treating unit configured to receive a gas or a mixture of gases to be treated and to feed the packaging gas to the gas accumulator, the treating unit being configured to change a composition of the gas or mixture of gases to be treated to obtain the packaging gas.

[0018] In a 11th aspect in accordance with the preceding aspect, the treating unit is configured to electrically treat the gas or mixture of gases to be treated to obtain the packaging gas. In a 12th aspect, in accordance with either the 10th aspect or the 11th aspect, the treating unit is an ozone generator.

[0019] In a 13th aspect in accordance with any one of the aspects from the 10th to the 12th, the gas or mixture of gases to be treated comprises oxygen and the packaging gas comprises ozone.

[0020] In a 14th aspect in accordance with any one of the aspects from the 10th to the 13th, the treating unit is a plasma ozone generator.

[0021] In a 15th aspect in accordance with any one of the aspects from the 10th to the 14th, the treating unit is a high voltage plasma ozone generator.

[0022] In a 16th aspect in accordance with any one of the aspects from the 10th to the 15th, the gas feeder comprises a first valve coupled to and interposed between the gas source and the gas accumulator, wherein the first valve is configured to control a first pressure within the treating unit.

[0023] In a 17th aspect in accordance with any one of the preceding aspects, the gas feeder comprises a vent coupled to the outlet of the portion, the vent being configured to receive the packaging gas from the outlet and release the packaging gas into an environment. In a 18th aspect in accordance with the preceding aspect, the vent comprises a converter configured to receive the packaging gas and treat the packaging gas to obtain an environmentally friendly gas.

[0024] In a 19th aspect in accordance with the preceding aspect, the converter is a catalytic converter.

[0025] In a 20th aspect in accordance with any one of the preceding aspects, the gas feeder comprises a first line and a second line each coupled to the outlet of the portion, wherein:

• the outlet is configured to feed the packaging gas to the first line and to the second line,
• the outlet is configured to be coupled to the workstation through the second line.

[0026] In a 21st aspect in accordance with the preceding aspect when combined with any one of the aspects from the 17th to the 19th, the outlet is coupled to the vent through the first line.

[0027] In a 22nd aspect in accordance with the preceding aspect, the gas feeder comprises a second valve interposed between the gas accumulator and the vent along the first line, the second valve being configured to control a second pressure within the gas accumulator.

[0028] In a 23rd aspect in accordance with any one of the aspects from the 20th to the 22nd, the gas feeder comprises a monitoring unit along the first line or the second line and coupled to the outlet to receive the packaging gas, the monitoring unit being configured to generate a sensor signal representative of a chemical composition and/or of a flow rate of the packaging gas.

[0029] In a 24th aspect in accordance with the preceding aspect when combined with the 22nd aspect, the monitoring unit is located between the second valve and the vent along the first line, the monitoring unit being configured to receive the packaging gas when the second pressure exceeds a reference pressure.

[0030] A 25th aspect concerns a system for manufacturing modified atmosphere packages which comprises:

• a gas feeder according to any one of the preceding aspects,
• a workstation of a packaging machine coupled to the outlet to receive the packaging gas.

[0031] In a 26th aspect in accordance with the preceding aspect, the gas feeder is in accordance with any one of the preceding aspects when combined with the 23rd aspect, the system comprises a control unit in signal communication with the monitoring unit and the workstation.

[0032] In a 27th aspect in accordance with the preceding aspect, the control unit is configured to:

• receive sensor signal from the monitoring unit,
• receive reference operating parameters representative of a reference chemical composition and/or of a reference flow rate of the packaging gas,
• control the workstation based on the sensor signal and reference operating parameters. In a 28th aspect in accordance with the preceding aspect, the control unit is in signal communication with the gas source, the control unit being configured to control the gas source based on the sensor signal and reference operating parameters.

[0033] A 29th aspect concerns a method for packaging modified atmosphere packages using a system in accordance with the aspects from the 25th to the 28th aspect, comprising the steps of:

• feeding packaging gas to the gas accumulator,
• generating a sensor signal representative of a chemical composition and/or of a flow rate of the packaging gas fed to the gas accumulator,
• receiving reference operating parameters representative of a reference chemical composition and/or of a reference flow rate of the packaging gas,
• feeding packaging gas to the workstation based on the sensor signal and reference operating parameters.

[0034] In a 30th aspect, the step of generating a sensor signal comprises determining an ozone concentration in the packaging gas.

BRIEF DESCRIPTION OF THE DRAWING

[0035] The foregoing aspects and many of the attendant advantages of the disclosed subject matter will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:

• Fig. 1 shows a diagrammatic view of a system comprising a gas feeder for packaging machine in accordance with embodiments described herein,
• Fig. 2 shows a diagrammatic view of a system comprising a gas feeder for packaging machine in accordance with the embodiments described herein,
• Fig. 3, 4, 5, 6 are top views of a portion of a conduit of the gas feeder in accordance with embodiments described herein,
• Figs. 3A, 3B are cross-sectional views of the portion of Fig. 3 respectively according to the transverse section plane IIIA-IIIA and IIIB-IIIB,
• Figs. 4A, 4B are cross-sectional views of the portion of Fig. 4 respectively according to the transverse section plane IVA-IVA and IVB-IVB,
• Figs. 5A, 5B are cross-sectional views of the portion of Fig. 5 respectively according to the transverse section plane VA-VA and VB-VB,
• Fig. 6A is a cross-sectional view of the portion of Fig. 6 according to the transverse plane VIA-VIA,
• Figs. 7-10 are cross-sectional views of a portion of a conduit of the gas feeder in accordance with embodiments described herein.

DETAILED DESCRIPTION

[0036] The present disclosure describes a gas feeder 1 for a packaging machine. The gas feeder 1 comprises a gas source 2 and a gas accumulator 3 in fluid communication with each other. The gas source 2 is configured to feed a packaging gas to the gas accumulator 3. The gas accumulator 3 is configured to accommodate packaging gas. The gas accumulator 3 comprises a portion 30 of a conduit. The portion 30 extends for a length from an inlet 4 to an outlet 5 along a path. The portion 30 is configured to guide the packaging gas along the path.

[0037] The path may be a rectilinear path, as shown in Figs. 3, 4, 5, or a non-rectilinear path as shown in Figs. 1, 2, 6. In detail, the path may be a helix path. More in detail, the path may be around a direction of transfer defined by a direction which connects the inlet 4 and the outlet 5 of the conduit. In other words, the portion 30 may extend along any curve or path which connects the inlet 4 to the outlet 5.

[0038] In embodiment, the conduit is made of one among polyethylene, copper, steel, galvanized steel, PVC, ABS, chromed brass, CPVC or PEX. In an embodiment, the gas feeder 1 comprises a pipe defining the conduit. The pipe may be a PEX pipe. For example, in case of a coiled pipe the path is a helix path.

[0039] In an embodiment, the length of the portion of the conduit is defined as a distance from the inlet 4 to the outlet 5 that the packaging gas travels when passing through the portion. In detail, the length of the portion 30 may be greater than or equal to 5 meters, preferably greater than or equal to 10 meters, more preferably greater than or equal to 20 meters, even more preferably greater than or equal to 30 meters.

[0040] The portion 30 presents a maximum flux cross-sectional area 31a at a first cross-section 31 and a minimum flux cross-sectional area 32a at a second cross-section 32. The maximum flux cross-sectional area 31a is greater than or equal to the minimum flux cross-sectional area 32a. In other words, the portion presents either a constant flux cross-sectional area or a maximum flux cross-sectional area 31a at a first cross-section that is greater than the minimum flux cross-sectional area 31a at a second cross-section. The maximum and minimum flux cross-sectional areas 31a, 32a are the areas available for the gas to pass through the respective first cross-section 31 and second cross-section 32.

[0041] The inlet 4 of the portion 30 is coupled to the gas source 2 to receive the packaging gas. The outlet 5 of the portion 30 is configured to be coupled to a workstation 6 of a packaging machine to feed the packaging gas to the workstation 6. The portion 30 is configured to guide the packaging gas from the inlet 4 to the outlet 5 along the path. The workstation may be a sealing station of a packaging machine adapted to receive the packaging gas and inject it inside a chamber to package a modified atmosphere package. In other words, in use, the packaging gas passes from the gas source to the workstation via the gas accumulator, in particular through the conduit.

[0042] The gas accumulator defines an accumulation volume in which the packaging gas fed by the gas source is accumulated. In some embodiments, the accumulation volume is configured to accommodate a volume of packaging gas which is greater from 10% to 500%, preferably from 50% to 200%, with respect to the volume of gas needed by the workstation for a cycle of the packaging process. For example, in case of a sealing station as workstation, a cycle of the packaging process may comprise the steps of receiving a tray containing a product in a sealing chamber, injecting the packaging gas in the sealing chamber towards the tray such that the gas present in the tray is replaced at least in part with the packaging gas, sealing a film to the tray such that a modified atmosphere package is obtained.

[0043] A ratio of the length to a square root of the maximum flux cross-sectional area 31a is greater than or equal to 100. In some embodiments, the ratio is greater than or equal to 500, preferably greater than or equal to 1000, more preferably greater than or equal to 1500, even more preferably greater than or equal to 2000.

[0044] Advantageously, the gas feeder having the ratio as described allows to decrease the transition time needed to reach steady state after a step change in the packaging gas composition thus reducing or eliminating the number of rejected packages containing a not-suitable gas. Indeed, the transition time needed to obtain the suitable packaging gas after a step change in the composition can be decreased by more than 70%.

[0045] For example, a known type of gas feeder with an accumulator, whose ratio is about equal to 5, presents a transition time of 68 seconds while the gas feeder of the invention with a ratio of about 2700 presents a transition time of 18 seconds for about the same gas accumulation volume, pressure, and flow rate conditions.

[0046] Fig. 3 shows a top view of a portion having a rectilinear path and a cylindrical shape. Figs. 3A and 3B are cross section views of the portion of Fig. 3 respectively according to transverse plane IIIA-IIIA and IIIB-IIIB. In the embodiment shown in Fig. 3, the maximum flux cross-sectional area 31a is equal to the minimum flux cross-sectional area 32a. In other words, the flux cross-sectional area of the portion of Fig. 3 is constant along the path from the inlet to the outlet.

[0047] In the embodiments shown in Fig. 4 and 5, the flux cross-sectional area of the portion 30 is not constant along the path. In other words, the maximum flux cross-sectional area 31a at the first cross-section 31 is greater than the minimum flux cross-sectional area 32a at the second cross section 32.

[0048] Fig. 4A depicts a cross-sectional view of the portion of Fig. 4 according to the transverse plane IVA-IVA showing the minimum flux cross-sectional area 32a at the second cross-section 32. Fig. 4B depicts a cross-sectional view of the portion of Fig. 4 according to the transverse plane IVB-IVB showing the maximum flux cross-sectional area 31a at the first cross-section 31.

[0049] Fig. 5A depicts a cross-sectional view of the portion of Fig. 5 according to the plane VA-VA showing the maximum flux cross-sectional area 31a at the first cross-section 31. Fig. 5B depicts a cross-sectional view of the portion of Fig. 5 according to the plane VB-VB showing the minimum flux cross-sectional area 32a at the second cross-section 32.

[0050] The first and the second cross-sections 31, 32, and consequently the maximum and minimum flux cross-sectional area 31a, 32a, may present any shape and conformation. In some embodiments, the first cross-section 31 and second cross-section 32 are circular or elliptical. Each one of figs. 3A, 4B, 5A and 6A depicts a circular first cross-section 31. Each one of figs. 3B, 4A, 5B depicts a circular second cross-section 32. An elliptical first cross-section is depicted in Fig. 7.

[0051] In some embodiments, the first cross-section 31 and second cross-section 32 are rectangular or square, as shown in Figs. 9 and 10, wherein only the first-cross section is depicted.

[0052] Although for some embodiments only the first cross-section is depicted, it is to be understood that both the first and the second cross-section can be circular, elliptical, rectangular, or square.

[0053] In an embodiment, a percentage ratio of the maximum flux cross-sectional area 31a to the minimum flux cross-sectional area 32a is less than or equal to 300%, preferably less than or equal to 250%, more preferably less than or equal to 200%. In some embodiments, the percentage ratio of the maximum flux cross-sectional area 31a to the minimum flux cross-sectional area 32a is equal to 100%.

[0054] Advantageously, a percentage ratio of the maximum to the minimum flux cross-sectional areas as described allows to limit the variation of the gas pressure and gas velocity inside the portion, thus minimizing flux turbulences.

[0055] In some embodiments, the gas source 2 comprises a treating unit 7 configured to receive a gas or a mixture of gases to be treated and to feed the packaging gas to the gas accumulator 3. The treating unit 7 is configured to change a composition of the gas or mixture of gases to be treated to obtain the packaging gas. The treating unit 7 may be in fluid communication with a gas storage unit 15 to receive the gas or mixture of gases to be treated. The gas storage unit 15 can be a tank or multiple tanks containing the gas or mixture of gases to be treated or any kind of device useful to accumulate and feed gas to the treating unit 7. In some embodiments, the treating unit 7 may be configured to electrically treat the gas or mixture of gases to be treated to obtain the packaging gas.

[0056] In an embodiment, the treating unit 7 is an ozone generator. The treating unit 7 may be a plasma ozone generator. More in particular, the treating unit 7 may be a high voltage plasma ozone generator. The treating unit 7 may be a low voltage plasma ozone generator. The treating unit 7 can be configured to generate 10 to 600 grams of ozone per hour from 5 to 600 liters per minute of oxygen. In one embodiment, the treating unit 7 is configured to generate ten grams of ozone per hour from five liters per minute of oxygen. The gas or mixture of gases to be treated comprises oxygen and the packaging gas comprises ozone. In particular, the treating unit 7 may be configured to control a concentration of ozone in the packaging gas.

[0057] In some embodiments, the concentration of ozone in the packaging gas is between 1000 and 22000 parts per million by volume. In some embodiments, the concentration of ozone is between 4000 and 18000 parts per million by volume. In detail, the concentration of ozone is between 12000 and 17000 parts per million by volume. Advantageously, this concentration of ozone of the packaging gas allows to manufacture packages with reduced microbial contamination within the package interior. The gas feeder 1 as described is suitable for the manufacturing of modified atmosphere packages and for the gas flushing of packages that contain products. Therefore, the gas feeder 1 herein disclosed allows to package medical devices or food products with reduced microbial contamination.

[0058] In some embodiments, the gas feeder 1 comprises a first valve 8 coupled to and interposed between the gas source 2 and the gas accumulator 3. The first valve 8 is coupled to the treating unit 7. The first valve 8 is configured to control a first pressure within the treating unit 7. The first valve 8 is configured to limit the first pressure within the treating unit 7. In an embodiment, the first valve 8 is a back pressure regulating valve. Advantageously, the first valve 8 limits the influence of the workstation 6 and of the related packaging process on the treating unit 7. In other words, the first valve 8 ensures that the treating unit 7 is not affected by changes in pressure downstream the first valve 8. In fact, during the operation of the workstation 6 it could happen that the intermittent request of gas flow into the workstation of the packaging machine changes the pressure downstream the first valve 8, i.e., downstream the gas source 2. Advantageously, the first valve 8 by maintaining the treating unit 7 at constant pressure and flow rate allows a constant ozone generation.

[0059] In an embodiment, the gas feeder 1 comprises a vent 9 coupled to the outlet 5 of the portion. The vent 9 is configured to receive the packaging gas from the outlet 5 and release the packaging gas into an environment.

[0060] In some embodiments, the vent 9 comprises a converter configured to receive the packaging gas and treat the packaging gas to obtain an environmentally friendly gas. The converter may be a catalytic converter. Advantageously, the converter can be configured to reduce the concentration of ozone of the packaging gas before it is released into the environment.

[0061] In some embodiments, the gas feeder 1 comprises a first line 10 and a second line 11 each coupled to the outlet 5 of the portion 30. The outlet 5 is configured to feed the packaging gas to the first line 10 and to the second line 11. In detail, the outlet 5 of the portion 30 is configured to be coupled to the workstation 6 through the second line 11. The outlet 5 of the portion 30 is coupled to the vent 9 through the first line 10. In other words, the first line 10 is configured to guide the packaging gas from the outlet 5 of the portion of the conduit to the vent 9. On the other hand, the second line 11 is configured to guide the packaging gas from the outlet 5 of the portion of the conduit to the workstation 6 of the packaging machine. In other words, the first line and the second line respectively allow the fluid communication between the gas accumulator and the vent and between the gas accumulator and the workstation.

[0062] In some embodiments, the gas feeder 1 comprises a second valve 12 interposed between the gas accumulator 3 and the vent 9 along the first line 10. The second valve 12 is configured to control a second pressure within the gas accumulator 3. In an embodiment, the second valve 12 is a back pressure regulating valve. The second valve 12 is configured to limit the second pressure within the accumulator 3.

[0063] In an embodiment, the second valve 12 is configured to:

• enable the fluid communication between the gas accumulator 3 and the vent 9 when the second pressure is above a reference pressure, and/or
• impede or prevent the fluid communication between the gas accumulator 3 and the vent 9 when the second pressure is below a reference pressure.

[0064] Advantageously, the second valve 12 assures that the second pressure within the accumulator 3 does not increase at hazardous levels, thus increasing the reliability and safety of the gas feeder 1. More advantageously, the first line 10 with the second valve 12 allows the gas source 2 to run and feed gas continuously without over-pressurizing the accumulator 3 even if the accumulator 3 is not feeding the packaging gas to the workstation 6.

[0065] In some embodiments, the gas feeder 1 comprises a monitoring unit 13 along the first line 10 or the second line 11. The monitoring unit 13 is coupled to the outlet 5 of the portion of the conduit to receive the packaging gas.

[0066] In detail, the monitoring unit 13 is configured to generate a sensor signal representative of a chemical composition and/or of a flow rate of the packaging gas. More in detail, the sensor signal may be representative of the concentration of ozone and/or of the flow rate of the packaging gas. Advantageously, the monitoring unit by providing real-time feedback on the concentration of ozone and/or on the flow rate allows to constantly verify the suitability of the packaging gas for the packaging process.

[0067] In some embodiments, the monitoring unit 13 is located along the first line 10. In particular, the monitoring unit 13 is located between the second valve 12 and the vent 9 along the first line 10. The monitoring unit 13 is configured to receive the packaging gas when the second pressure exceeds the reference pressure.

[0068] In some embodiments, the gas feeder 1 comprises a third valve 16 coupled to the outlet 5 of the portion of the conduit through the second line 11. The third valve 16 is configured to be located along the second line 11 between the outlet 5 of the portion and the workstation 6.

[0069] In an embodiment, the third valve 16 defines a passage condition and a closure condition. When in the passage condition, the third valve 16 enables the fluid communication between the accumulator 3 and the workstation 6. When in the closure condition, the third valve 16 interdicts the fluid communication between the accumulator 3 and the workstation 6.

[0070] The present disclosure is also directed to a system 100 for manufacturing packages that comprises a gas feeder 1 as herein described and a workstation 6 coupled to the outlet 5 to receive the packaging gas. Preferably, the system 100 is suitable for manufacturing modified atmosphere packages and/or gas flushed packages.

[0071] The workstation may be a sealing station of a modified atmosphere packaging machine. The modified atmosphere packaging machine may be a tray lidding packaging machine. In some embodiments, the system 100 comprises a control unit 14 in signal communication with the monitoring unit 13 and the workstation 6. The system described herein includes at least one control unit, the control unit can clearly be only one or be formed by a plurality of different control units according to the design choices and the operational needs.

[0072] The control unit 14 is configured to:

• receive sensor signal from the monitoring unit 13,
• receive reference operating parameters representative of a reference chemical composition and/or of a reference flow rate of the packaging gas,
• control the workstation 6 based on the sensor signal and reference operating parameters.

[0073] In an embodiment, the control unit 14 is configured to establish if the composition and/or the flow rate of the packaging gas is suitable for a packaging process. More in detail, the control unit 14 is configured to respectively compare the composition and/or the flow rate of the packaging gas monitored by the monitoring unit 13 with the reference chemical composition and/or reference flow rate.

[0074] The control unit 14 can be in signal communication with either the first valve 8 or the second valve 12 or both the first and second valves 8,12. The control unit 14 may be configured to control the first valve 8 and/or the second valve 12 to limit or adjust respectively the first pressure and/or the second pressure.

[0075] In an embodiment, the system 100 comprises a pressure sensor coupled to the gas accumulator and configured to generate a pressure signal representative of the second pressure.

[0076] The control unit 14 may be in signal communication with the pressure sensor and the second valve 12 and configured to:

• receive the pressure signal representative of the second pressure,
• receive a reference pressure data representative of the reference pressure,
• control the second valve 12 based on the pressure signal representative of the second pressure and the reference pressure data to enable or interdict the fluid communication between the gas accumulator and the vent 9.

[0077] In an embodiment, the system 100 comprises a further pressure sensor coupled to the treating unit 7 and in signal communication with the control unit 14. The further pressure sensor is configured to generate a pressure signal representative of the first pressure. The control unit 14 may be in signal communication with the first valve 8 to control the first valve 8 based on the pressure signal representative of the first pressure and a further reference pressure.

[0078] In an embodiment, the control unit 14 is configured to receive the reference operating parameters and/or the reference pressure data from a data storage in signal communication with the control unit 14. The data storage may be any appropriate memory banks connected to the control unit 14 and able to store the reference operating parameters and/or the reference pressure data.

[0079] In some embodiments, the control unit 14 is in signal communication with the third valve 16 and configured to control the third valve based on the sensor signal received from the monitoring unit and reference operating parameters. In detail, the control unit 14 is configured to move the third valve 16 between the passage condition and the closure condition based on the sensor signal and the reference operating parameters. Advantageously, the control unit 14 as described allows to actively enable or interdict the fluid communication between the accumulator 3 and the workstation 6 according to the concentration of ozone and/or the flow rate of the packaging gas. This assures that only the packaging gas with a suitable concentration of ozone is fed to the workstation thus increasing the reliability of the system and decreasing the number of rejected packages.

[0080] The present disclosure is also directed to a method for manufacturing packages using the system described herein. Preferably, the method is suitable for manufacturing modified atmosphere packages and/or gas flushed packages. The method comprises the steps of:

• feeding packaging gas to a gas accumulator 3,
• generating a sensor signal representative of a chemical composition and/or of a flow rate of the packaging gas fed to the gas accumulator 3,
• receiving reference operating parameters representative of a reference chemical composition and/or of a reference flow rate of the packaging gas,
• feeding packaging gas to the workstation 6 based on the sensor signal and reference operating parameters.

[0081] In an embodiment, the method comprises determining an ozone concentration in the packaging gas. The reference chemical composition may be a reference ozone concentration in the packaging gas.

[0082] In an embodiment, the step of feeding the packaging gas to the workstation comprises establishing if the packaging gas is suitable for the packaging process. In particular, the step of feeding the packaging gas to the workstation may comprise the step of establishing if the ozone concentration in the packaging gas is above the reference ozone concentration.

[0083] In an embodiment, the method further comprises the steps of:

• feeding a gas or mixture of gases to be treated to a treating unit in fluid communication with the gas accumulator,
• changing the composition of the gas or mixture of gases to be treated to obtain the packaging gas.

[0084] In an embodiment, the step of changing the composition of the gas or mixture of gases to be treated comprises generating a plasma within a chamber containing the gas or mixture of gases to be treated.

[0085] For purposes of this disclosure, terminology such as "upper", "lower", "vertical", "horizontal", "inwardly", "outwardly", "inner", "outer", "front", "rear", and the like, should be construed as descriptive and not limiting the scope of the claimed subject matter. Further, the use of "including", "comprising" or "having" and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless limited otherwise, the terms "connected", "coupled", and mounted" and variations thereof herein are used broadly and encompass direct and indirect connections, couplings, and mountings. Unless stated otherwise, the terms "substantially", "approximately" and the like are used to mean within 5% of a target value.

[0086] The representative embodiments and modes of operation of the present disclosure have been described in the foregoing description. However, aspects of the present disclosure which are intended to be protected are not to be construed as limited to the particular embodiments disclosed. Further, the embodiments described herein are to be regarded as illustrative rather than restrictive. It will be appreciated that variations and changes may be made by others, and equivalents employed, without departing from the present disclosure. Accordingly, it is expressly intended that all such variations, changes, and equivalents fall within the scope of the present disclosure, as claimed.

Claims

1. A gas feeder (1) for a packaging machine comprising a gas source (2) and a gas accumulator (3) in fluid communication with each other, the gas source (2) being configured to feed a packaging gas to the gas accumulator (3), the gas accumulator (3) comprising a portion (30) of a conduit extending for a length from an inlet (4) to an outlet (5) along a path, the portion (30) being configured to guide the packaging gas along the path, wherein:

- the portion (30) presents a maximum flux cross-sectional area (31a) at a first cross-section (31) and a minimum flux cross-sectional area (32a) at a second cross-section (32), the maximum flux cross-sectional area (31a) being greater than or equal to the minimum flux cross-sectional area (32a),

- the inlet (4) is coupled to the gas source (2) to receive the packaging gas,

- the outlet (5) is configured to be coupled to a workstation (6) of a packaging machine to feed the packaging gas to the workstation (6),

characterized by the fact that a ratio of the length to a square root of the maximum flux cross-sectional area (31a) is greater than 100.

2. The gas feeder (1) of the preceding claim, wherein a percentage ratio of the maximum flux cross-sectional area (31a) to the minimum flux cross-sectional area (32a) is less than or equal to 300%, preferably less than or equal to 250%, more preferably less than or equal to 200%.

3. The gas feeder (1) of any one of the preceding claims, wherein the first cross-section (31) and second cross-section (32) are circular or elliptical.

4. The gas feeder (1) of any one of the preceding claims, wherein the length of the portion (30) is greater than or equal to 5 meters, preferably greater than or equal to 10 meters, more preferably greater than or equal to 20 meters, even more preferably greater than or equal to 30 meters.

5. The gas feeder (1) of any one of the preceding claims, wherein the ratio of the length to the square root of the maximum flux cross-sectional area (31a) is greater than 500, preferably greater than 1000, more preferably greater than 1500, even more preferably greater than 2000.

6. The gas feeder (1) of the any one of the preceding claims, wherein the gas source (2) comprises a treating unit (7) configured to receive a gas or a mixture of gases to be treated and to feed the packaging gas to the gas accumulator (3), the treating unit (7) being configured to change a composition of the gas or mixture of gases to be treated to obtain the packaging gas.

7. The gas feeder (1) of the preceding claim, wherein:

- the treating unit (7) is an ozone generator,

- the gas or mixture of gases to be treated comprises oxygen,

- the packaging gas comprises ozone.

8. The gas feeder (1) of the preceding claim, wherein the treating unit (7) is a plasma ozone generator.

9. The gas feeder (1) of any one of claims 6 to 8, comprising a first valve (8) coupled to and interposed between the gas source (2) and the gas accumulator (3), the first valve (8) being configured to control a first pressure within the treating unit (7).

10. The gas feeder (1) of any one of the preceding claims, comprising a vent (9) coupled to the outlet (5) of the portion (30), the vent (9) being configured to receive the packaging gas from the outlet (5) and release the packaging gas into an environment.

11. The gas feeder (1) of the preceding claim, comprising a first line (10) and a second line (11) each coupled to the outlet (5) of the portion (30), wherein:

- the outlet (5) is configured to feed the packaging gas to the first line (10) and to the second line (11),

- the outlet (5) is configured to be coupled to the workstation (6) through the second line (11),

- the outlet (5) is coupled to the vent (9) through the first line (10).

12. The gas feeder (1) of the preceding claim, comprising a second valve (12) interposed between the gas accumulator (3) and the vent (9) along the first line (10), the second valve (12) being configured to control a second pressure within the gas accumulator (3).

13. The gas feeder (1) according to claim 11 or 12, comprising a monitoring unit (13) along the first line (10) or the second line (11) and coupled to the outlet (5) of the portion (30) to receive the packaging gas, the monitoring unit (13) being configured to generate a sensor signal representative of a chemical composition and/or of a flow rate of the packaging gas.

14. The gas feeder (1) of the preceding claim when combined with claim 12, wherein the monitoring unit (13) is located between the second valve (12) and the vent (9) along the first line (10), the monitoring unit (13) being configured to receive the packaging gas when the second pressure exceeds a reference pressure.

15. A system (100) for manufacturing packages, preferably modified atmosphere packages, comprising:

- a gas feeder (1) according to any one of the preceding claims,

- a workstation (6) of a packaging machine coupled to the outlet (5) to receive the packaging gas.

16. The system (100) of the preceding claim, wherein the gas feeder (1) is according to claim 13 or claim 14, comprising a control unit (14) in signal communication with the monitoring unit (13) and the workstation (6), wherein the control unit (14) is configured to:

- receive sensor signal from the monitoring unit (13),

- receive reference operating parameters representative of a reference chemical composition and/or of a reference flow rate of the packaging gas,

- control the workstation (6) based on the sensor signal and reference operating parameters.

17. A method for manufacturing packages using a system according to the preceding claims 15 or 16, comprising the steps of:

- feeding packaging gas to the gas accumulator (3),

- generating a sensor signal representative of a chemical composition and/or of a flow rate of the packaging gas fed to the gas accumulator (3),

- receiving reference operating parameters representative of a reference chemical composition and/or of a reference flow rate of the packaging gas,

- feeding packaging gas to the workstation (6) based on the sensor signal and reference operating parameters.

18. The method of the preceding claim, comprising the step of determining an ozone concentration in the packaging gas.

Drawing