Apparatus and method for supplying pulsed air

Abstract

A valve (30) for delivering pulses of sterile air to a web of packaging material (20) is provided. The valve includes a rotatable valve shaft (31) having an inlet portion (32) with a circular cross-section, the inlet portion (32) including a radial slot (33) connected to an axial cavity (34) in the valve shaft (31). The valve (30) further includes a curved end (36) adapted to fit against an outer surface of the inlet portion (32) of the valve shaft (31) during rotation of the valve shaft (31), and a valve member (35) including a fluid channel (37) extending through the valve member (35), such that air can flow through the valve (30) via the valve member (35) and valve shaft (31) when the radial slot (33) in the inlet portion (32) is rotated to a position where it aligns with the fluid channel (37) in the valve member (35).

Description

Technical Field

[0001] The present invention generally relates to the field of air pulse technology and its valves. More specifically, it relates to valves, devices, and methods capable of removing excess sterilizing agents from a web of packaging material.

Background Art

[0002] It is well known to use roll-fed packaging machines to manufacture individual packages of different types of food, such as milk. One advantage of using such a packaging machine is that it can speed up the continuous production of packages.

[0003] The packaging material is sterilized using a sterilizing agent such as hydrogen peroxide so that unwanted germs and microorganisms do not adhere to the packaging material. However, for various reasons, it is necessary to remove the sterilizing agent before filling the product.

[0004] In the manufacture of such packages, the web of packaging material is fed through various stations for sterilization, tube forming, filling, sealing, and final forming. When passing through the sterilization station, the packaging material is immersed in the sterilizing agent. Thereafter, the packaging material passes through a nip formed by two rollers, and the sterilizing agent spreads and forms a uniform film covering the web of packaging material from both sides. Thereafter, sterilization is efficiently performed by applying heat to evaporate the sterilizing agent.

[0005] The web of packaging material may have protruding structures such as injection-molded opening devices. In such protruding structures, the sterilizing agent may not spread in a uniform film, and as a result, an excessive amount of the sterilizing agent may be present around these structures. Since this excessive sterilizing agent does not evaporate properly in the heating process, the sterilizing agent may remain inside or outside the packaging material.

[0006] Therefore, even when the packaging material has a protruding structure such as the above-described opening device, it is necessary to provide a solution capable of uniformly distributing the sterilizing agent. [Overview of the project] [Problems that the invention aims to solve]

[0007] The object of the present invention is to overcome at least partially one or more of the limitations of the prior art described above. [Means for solving the problem]

[0008] The idea behind this invention is to remove disinfectant from protruding structures by pulse-blowing sterile air onto the web of the packaging material. By pulse-blowing, areas with excessive disinfectant on the web can be precisely targeted. Furthermore, it is possible to prevent undesirable removal of disinfectant from areas where it has been properly applied.

[0009] While pulsed air blowing technology currently exists, further technological improvements are needed to achieve greater efficiency in terms of speed, air volume, component durability, and hygiene, in order to maximize the capabilities of roll-feed packaging machines.

[0010] The objective of the present invention is to provide a valve capable of generating high-speed pulses of sterile air.

[0011] According to a first embodiment, a valve is provided for supplying a pulse of sterile air to a web of packaging material. The valve, The valve comprises a rotatable valve shaft having an inlet portion having a circular cross-section, the inlet portion having a radial slot connected to an axial cavity of the valve shaft. The valve further comprises The valve comprises a valve member having a curved end that conforms to the outer surface of the inlet portion of the valve shaft as the valve shaft rotates, and a fluid channel extending into the valve member, so that when the valve shaft is rotated to a position where the radial slot of the inlet portion coincides with the fluid channel of the valve member, air can flow through the valve member and valve shaft. The advantage of these features of the valve is that it can generate high-speed, distinct pulses of air.

[0012] According to one embodiment, in order to rotate the valve shaft, the valve includes a drive unit connected to the valve shaft. The valve opening time (length) can be adjusted by using the drive unit to operate the valve at different rotational speeds as the slot passes through the valve opening.

[0013] According to one embodiment, the valve member includes a discharge slot, which releases air when the radial slot of the valve shaft is aligned with the discharge slot. The advantage of having a discharge slot is that it prevents air leakage into the web of the packaging material immediately after an air pulse.

[0014] According to one embodiment, the circumferential width of the radial slot is within the range of 1 to 10%, preferably 1 to 5%, of the entire circumference of the inlet portion. According to one embodiment, the circumferential width of the radial slot is smaller than the width of the fluid channel of the valve member. The advantage of these features regarding circumferential width is that it provides a fast opening and closing time for the valve, resulting in a clear, square-shaped air pulse.

[0015] According to one embodiment, the inlet portion 32 includes a plurality of spaced radial slots, each connected to an axial cavity of the valve shaft. The advantage of this feature is that it provides multiple air pulses for each rotation of the shaft member, minimizing wear on the components and reducing the power required.

[0016] According to a second aspect, an apparatus is provided for supplying pulses of sterile air to a web of packaging material, the web of packaging material comprising a number of sequentially arranged sections arranged to form individual packages, at least a subset of the sections including positioning elements. The apparatus comprises a positioning element reader for measuring the time it takes for a positioning element to pass a positioning element reader, a valve for supplying pulses of sterile air according to the first aspect described above, and a control unit for controlling the operation of the valve based on the output of the positioning element reader.

[0017] According to one embodiment, the device further includes a nozzle that supplies air pulses to one or both sides of the web of the packaging material. Thus, simultaneous air pulses are achieved not only on the outside but also on the inside of the web of the packaging material.

[0018] According to one embodiment, the device further includes a pressure sensor located downstream of the valve shaft. The advantage of this is that it can verify the correct timing and correct air pressure of the air pulse.

[0019] A third aspect provides a method for removing excess sterilizing agent from a web of packaging material. The method includes providing a valve having a rotatable valve shaft and a valve member fitted to fit with the valve shaft, rotating the valve shaft so that a radial slot of the valve shaft is in fluid communication with a fluid channel of the valve member, thereby allowing air to flow through the valve via the valve member and the valve shaft.

[0020] The advantage of this method is that it is efficient in terms of speed, as the web of packaging material can pass through the valve at high speed, allowing the roll-feed packaging machine used to manufacture packages from the web to operate at its maximum capacity.

[0021] According to one embodiment, the web of packaging material consists of a number of continuously arranged sections arranged to be formed into packages, and at least a subset of the sections includes positioning elements. In such an embodiment, the method further comprises measuring when the positioning element passes through a positioning element reader and calculating when a desired region of the web of packaging material passes through a valve based on the output of the positioning element reader, and the step of rotating the valve shaft is executed at the calculated time. By selectively using the rotational speed when the slot passes through the opening of the valve, the opening time (length) of the valve can be adjusted.

[0022] Still other objects, features, aspects and advantages of the present invention will become apparent from the following detailed description and the drawings.

[0023] Hereinafter, embodiments of the present invention will be illustratively described with reference to the accompanying schematic drawings.

Brief Description of the Drawings

[0024] [Figure 1a] Figure 1a is a perspective view of the components of a roll-fed packaging machine equipped with a device for supplying pulses of sterile air according to an embodiment. [Figure 1b] Figure 1b is a top view showing an example of a web of packaging material used with a valve according to various embodiments. [Figure 2] Figure 2 is a perspective view showing the components of the device shown in Figure 1. [Figure 3] Figure 3 is a perspective view showing the components of the device according to an embodiment. [Figure 4] Figure 4 is a perspective view showing the valve forming part of the device shown in Figure 3, with some components omitted. [Figure 5] Figure 5 is a cross-sectional view of a valve for supplying pulses of sterile air in an open position according to one embodiment. [Figure 6] Figure 6 is a cross-sectional view of the valve of Figure 5, showing the state in a closed position. [Figure 7]Figure 7 is a cross-sectional view of a valve supplying a pulse of sterile air according to an embodiment, shown in either the open position, the closed position, or the discharge position. [Figure 8] Figure 8 is a cross-sectional view of a valve supplying a pulse of sterile air according to an embodiment, shown in either the open position, the closed position, or the discharge position. [Figure 9] Figure 9 is a cross-sectional view of a valve for supplying a pulse of sterile air according to an embodiment, shown in either the open position, the closed position, or the discharge position. [Figure 10] Figure 10 is a flowchart showing a method for removing excess sterilizing agent from a web of packaging material according to one embodiment. [Modes for carrying out the invention]

[0025] Referring to Figure 1a, a part of the roll-feed type packaging machine 10 equipped with the device 40 will be described as an example.

[0026] During manufacturing, the web of the packaging material 20 is fed into the packaging machine 10 and passes through the packaging machine 10. To ensure that the packaging material 20 is free from bacteria and other unwanted microorganisms, the package is sterilized using a sterilizing agent. For example, the sterilizing agent may contain hydrogen peroxide. The roll-feed packaging machine 10 is equipped with a sterilization tank 11. As the web of the packaging material 20 passes through the sterilization tank 11, it is immersed in the sterilizing agent.

[0027] Next, the packaging material web 20 is conveyed through a nip formed by two rollers 12a-b, and a disinfectant is sprayed onto a uniform film covering both sides of the packaging material web 20 to remove any excess disinfectant. Subsequently, the web of the packaging material 20 is subjected to heat in a heating tower 13 for efficient sterilization and subsequent evaporation of the disinfectant, followed by tube forming, filling, sealing, and final forming. These steps, which convert the sterilized web of the packaging material 20 into individual packages, are performed by additional components (not shown) of the roll-feed packaging machine 10, which are not described further herein.

[0028] The web of the packaging material 20 may have protruding structures 22a to f, such as injection-molded opening devices, as illustrated with reference to Figure 1b, which shows an example of the web of the packaging material 20.

[0029] The web of the packaging material 20 may comprise a number of sequentially arranged sections 21a to f. Each of the number of sequentially arranged sections 21a to f may include attached opening devices 22a to f. At least a subset of the number of sequentially arranged sections 21a to f may include positioning elements 23a to f. For example, the positioning elements 23a to f may be integrated with the packaging material 20 so that their position is maintained during manufacturing.

[0030] The positioning elements 23a to f may be used to provide the packaging machine 10 with information regarding the position of the web 20. The positioning elements 23a to f may be marks and / or codes that can be read by a positioning element reader 45 (see Figure 1a), for example, by a photocell, camera, or tape reader. Alternatively, as an example, the positioning elements 23a to f may be provided as optical reference marks on the web of the packaging material 20, for example, as printed marks provided on the web. Alternatively, the positioning elements 23a to f may be printed magnetic marks detectable by a magnetic reader inside or outside the device 40. The positioning elements 23a to f may be any reference positions that provide information regarding the position of the web 20, and are not limited to this example. Furthermore, the positions of multiple sections 21a to f may be estimated using one of the positioning elements 23a to f.

[0031] In these protruding structures 22a-f, the disinfectant may accumulate and not be spread uniformly by the rollers 12a-b, resulting in excess disinfectant remaining in or near the protruding structures 22a-f. This excess disinfectant may not be properly evaporated in the heating tower 13, potentially leaving undesirable disinfectant residues on the inside and outside of the web of the packaging material 20.

[0032] It is recognized that by pulse-blowing sterile air onto the web of the packaging material 20 before the web of the packaging material 20 is exposed to heat, excess disinfectant in areas of the web of the packaging material 20 having protruding structures 22a-f can be removed. Pulse-blowing air allows for precise targeting on the web of the packaging material 20, for example, in areas where there is an excess of disinfectant. This offers several advantages. It helps avoid removing disinfectant from other areas where the disinfectant is actually spread properly. It also minimizes the amount of air used and turbulence. By using pulsed airflow rather than continuous airflow, the total amount of air used and energy used can be significantly reduced. Furthermore, since the air is directed only to small parts of the web 20, the air does not affect the temperature distribution of the packaging material 20 and does not have the potential to weaken the efficiency of the sterilization process.

[0033] Returning to Figure 1a, the roll-feed packaging machine 10 includes a device 40 for supplying pulses of sterile air to the web of the packaging material 20 to remove excess disinfectant.

[0034] The device 40 includes a valve 30 that supplies pulses of sterile air. The valve 30 comprises a valve member 35 and a valve shaft 31, which will be further described with reference to Figures 5-9. In one embodiment, the valve 30 further includes a drive unit 41 for adjusting the position of the rotatable valve shaft 31 of the valve 30. In one embodiment, the drive unit 41 is a servo motor. In another embodiment, the drive unit 41 is an electric motor.

[0035] In this embodiment, the apparatus 40 further includes a positioning element leader 45 that measures the time when the positioning elements 23a-f (see Figure 10) of the web of the packaging material 20 pass the positioning element leader 45. The control unit 46 is configured to control the operation of the valve 30 based on the output of the positioning element leader 45. The positioning element leader 45 and the control unit 46 can determine the timing when the positioning elements 23a-f pass the positioning element leader 45, and the control unit 46 is configured to calculate the timing when a desired area of ​​the web of the packaging material 20, i.e., the position of the protruding structures 22a-f, passes the valve 30. Such calculations are preferably based on the output of the positioning element leader 45, i.e., the detection time, the velocity of the web of the packaging material 20, the distance between the positioning elements 23a-f and the protruding structures 22a-f, and the temporal distance between the positioning element leader 45 and the nozzle of the valve 30 (given the velocity of the packaging material 20). The rotation of the valve shaft 31 is performed at the calculated time to open the valve 30 at the desired time.

[0036] In one embodiment, the protruding structures 22a to f may be detected by some other device, such as a camera. In this way, the valve 30 may be synchronized with a precise blow position for blowing air onto the protruding structures 22a to f.

[0037] In one embodiment, the device 40 further includes a pressure sensor 44 located downstream of the valve shaft 31. Measuring the air pressure at different points in time is used as part of the quality control of the device 40 to verify the correct air pressure at the correct time.

[0038] The apparatus 40 further comprises an air supply device 42 that supplies sterile air to the valve 30. In one embodiment, the air pressure provided by the air supply device 42 is 1.5 to 50 bar, preferably 20 bar. The valve 30 is positioned to be in direct fluid communication with the outlet of the air supply device 42.

[0039] Referring to Figure 2, a device 40 for supplying pulses of sterile air to the web of the packaging material 20 is illustrated. This device comprises a valve 30 for supplying pulses of sterile air, a drive unit 41 for adjusting the position of the valve shaft 31, an air supply unit 42 for supplying sterile air to the valve 30, and nozzles 43 positioned to supply air pulses from the valve 30 to both sides of the web of the packaging material 20.

[0040] The nozzle 43 constitutes an air outlet directed toward both sides of the web of the packaging material 20. The air outlet may be formed, for example, as a narrow channel, allowing air exiting the valve 30 to exit through the air outlet.

[0041] Referring to Figure 3, the device 40 is illustrated in more detail. This device comprises a valve 30 for supplying pulses of sterile air, a drive unit 41 for adjusting the position of a valve shaft 31 located inside a valve housing 30b, an air supply unit 42 for supplying sterile air to the valve 30, and a pressure sensor 44 located downstream of the valve shaft 31.

[0042] Referring to Figure 4, the valve 30 is shown without the housing 30b. The valve 30 comprises a rotatable valve shaft 31 having an inlet portion 32 with a circular cross-section and an axial cavity 34. The valve 30 further comprises a valve member 35 including a curved end 36 adapted to fit onto the outer surface of the inlet portion 32 of the valve shaft 31 as the valve shaft 31 rotates. A drive unit 41 is drive-coupled to the valve shaft 31 to adjust the position of the valve shaft 31. Air pressure from the air supply unit 42 presses the valve member 35 against the valve shaft 31.

[0043] The valve member 35 and valve shaft 31 are preferably made of durable materials such as stainless steel or aluminum. This is advantageous when used in the aforementioned packaging machine 10, which requires hygienic conditions and food-safe materials.

[0044] Referring to Figure 5, a cross-section of a valve 30 that supplies pulses of sterile air to the web of the packaging material 20 is shown in the open position. The rotatable valve shaft 31 includes an inlet portion 32 having a circular cross-section, the inlet portion 32 having a radial slot 33 connected to an axial cavity 34 of the valve shaft 31. The valve further includes a valve member 35 having a curved end 36 adapted to fit onto the outer surface of the inlet portion 32 of the valve shaft 31 during rotation of the valve shaft 31. The radial slot 33 is aligned circumferentially with the fluid channel 37 of the valve member 35 and axially with the fluid channel 37 extending through the valve member 35 so that air flows through the valve member 35 and the valve shaft 31 to the valve 30. The rotation of the valve shaft 31 is driven by a drive unit 41. By varying the rotational speed at which the slot 33 passes through the fluid passage 37 of the valve member 35, the opening time (length) of the valve 30 can be adjusted.

[0045] In Figure 6, the valve 30 is shown in its closed position. Here, the radial slot 33 of the inlet 32 ​​is rotated to a circumferential position that does not align with the fluid channel 37 of the valve member 35, thereby preventing air from passing through the valve member 35 and flowing along the valve shaft 31.

[0046] Referring to Figure 7, it is shown that the valve 30 is in the open position. Since the radial slot 33 of the inlet portion 32 is aligned with the fluid channel 37 of the valve member 35, it can be seen that air can flow continuously through the valve member 35 and the valve shaft 31.

[0047] The circumferential width of the radial slot 33 is preferably in the range of 1 to 10%, more preferably 1 to 5%, of the entire circumference of the inlet portion 32. More preferably, the circumferential width of the radial slot 33 is smaller than the width of the fluid channel 37 of the valve member 35. These features result in a fast valve opening and closing time, and consequently a fast opening time, resulting in a square-shaped air pulse. The valve shaft 31 may rotate at a constant speed, thereby resulting in the valve shaft 31 being in the open position for a much shorter time than it is in the closed position. It is also possible to change the rotational speed during rotation, thereby adapting the time the valve shaft is in the open and closed positions.

[0048] According to one embodiment, the inlet portion 32 may comprise a plurality of spaced radial slots 33, each connected to an axial cavity 34 of the valve shaft 31. The advantage of this feature is that more air pulses are possible per revolution of the valve shaft 31, thereby minimizing wear on components and reducing the power required.

[0049] Furthermore, the valve member 35 may be sealed on the outside with an O-ring 50 to prevent leakage from the air supply port 42 around the valve member 35.

[0050] Referring to Figure 8, it is shown that the valve is in the closed position. In the closed position, the valve shaft 31 rotates so that the radial slot 33 of the inlet portion 32 passes through the fluid channel 37 of the valve member 35, preventing air from flowing through the valve member 35 and the valve shaft 31.

[0051] Referring to Figure 9, the valve 30 is shown in the air discharge position. In the closed position, the axial cavity 34 and / or radial slot 33 of the inlet portion will contain overpressure of air from the air supply 42 that may leak through the nozzle after the valve is closed. To prevent such leakage, the valve shaft 31 is rotated to the air discharge position. In the air discharge position, the valve shaft 31 is rotated so that the radial slot 33 of the inlet portion 32 aligns with the discharge slot 38 of the valve member 35. The discharge slot 38 extends to the outer surface of the valve member 35 (shown in Figure 4), allowing air to exit from the axial cavity 34 and the radial slot 33 of the inlet portion 32, thereby reducing air leakage. Preferably, the discharge slot extends to the outer surface of the valve member 35 in a direction parallel to the axial cavity 34 of the valve shaft 31. The housing 30b (see Figure 3) constitutes an air outlet 39 that is in fluid communication with the discharge slot 38.

[0052] Referring to Figure 10, a method 100 for removing excess sterilizer from the web of packaging material 20 is schematically shown. Method 100 comprises a first step 102 of providing a valve 30 having a rotatable valve shaft 31 and a valve member 35 fitted to the valve shaft 31, and a step 104 of rotating the valve shaft 31 so that a radial slot 33 of the valve shaft 31 is in fluid communication with a fluid channel 37 of the valve member 35 and air flows through the valve member 35 and the valve shaft 31 to the valve 30.

[0053] Method 100 may further include optional steps 106 and 108. In step 106, the time it takes for positioning elements 23a-f to pass the positioning element leader 45 is measured. In step 108, the time it takes for a desired area of ​​the web of the packaging material 20 to pass the valve 30 is calculated based on the output of the positioning element leader 45, as described with reference to Figure 1. In embodiments including steps 106 and 108, step 104, in which the valve shaft 31 is rotated, is performed at the calculated time.

[0054] The desired area may be the web opening device 22a-f of the packaging material 20, and the positioning elements 23a-f may be of the type described with reference to Figure 1b. The control unit 46 controls the operation of the valve 30, thereby performing step 104 of rotating the valve shaft 31 in a time calculated based on the output of the positioning element leader 45, as further described above.

[0055] Although various embodiments of the present invention have been described and demonstrated above, the present invention is not limited thereto and can be embodied in other ways within the scope of the subject matter defined in the following claims.

Claims

1. A device (40) that supplies a pulse of sterile air to the web (20) of the packaging material, Valve (30) and The air supply device (42) connected to the valve (30), A nozzle (43) is arranged to supply air pulses to one or both sides of the web (20) of the packaging material, Equipped with, The valve (30) is A rotatable valve shaft (31) having an inlet portion (32) having a circular cross-section, wherein the inlet portion (32) includes a radial slot (33) connected to an axial cavity (34) of the valve shaft (31), The valve member (35) comprises a curved end (36) adapted to fit the outer surface of the inlet portion (32) of the valve shaft (31) as the valve shaft (31) rotates, and a fluid channel (37) extending through the valve member (35), wherein when the valve shaft (31) is rotated to a position where the radial slot (33) of the inlet portion (32) aligns with the fluid channel (37) of the valve member (35), air can flow through the valve member (35) and the valve shaft (31) through the valve (30). Apparatus (40).

2. The apparatus (40) according to claim 1, further comprising a drive device (41) connected to the valve shaft (31) for rotating the valve shaft (31).

3. The device (40) according to claim 2, wherein the drive device (41) is a servo motor or an electric motor.

4. The device (40) according to any one of claims 1 to 3, wherein the valve member (35) is provided with a discharge slot (38), and when the radial slot (33) of the valve shaft (31) is aligned with the discharge slot (38), air is released from the discharge slot.

5. The apparatus (40) according to claim 4, wherein the discharge slot (38) extends to the outer surface of the valve member (35).

6. The apparatus (40) according to any one of claims 1 to 5, wherein the circumferential width of the radial slot (33) is in the range of 1 to 10% of the entire circumference of the entrance portion (32).

7. The apparatus (40) according to any one of claims 1 to 6, wherein the circumferential width of the radial slot (33) is smaller than the width of the fluid channel (37) of the valve member (35).

8. The apparatus (40) according to any one of claims 1 to 7, further comprising a plurality of spaced radial slots (33) connected to the axial cavity (34) of the valve shaft (31).

9. The web (20) of the packaging material comprises a number of sequentially arranged sections (21a-f) arranged to form an individual package, wherein at least a subset of the sections (21a-f) comprises positioning elements (23a-f), The positioning element leader (45) measures when the positioning elements (23a to f) pass through the positioning element leader (45), A control device (46) controls the operation of the valve (30) based on the output of the positioning element leader (45), The apparatus (40) according to any one of claims 1 to 8, further comprising:

10. The apparatus (40) according to claim 1, wherein the nozzle (43) supplies air pulses to both sides of the web of the packaging material (20).

11. The apparatus (40) according to claim 9 or 10, further comprising a pressure sensor (44) positioned downstream of the valve shaft (31).

12. The apparatus (40) according to any one of claims 9 to 11, wherein the air pressure provided by the air supply device (42) is 1.5 to 50 Bar.

13. A method (100) for removing excess sterilizing agent from a web (20) of packaging material, The device (40) is provided to supply a pulse of sterile air to the web (20) of the packaging material (102), The device (40) includes a valve (30), The valve (30) is A rotatable valve shaft (31) having an inlet portion (32) having a circular cross-section, wherein the inlet portion (32) includes a radial slot (33) connected to an axial cavity (34) of the valve shaft (31), The valve member (35) comprises a curved end (36) adapted to fit the outer surface of the inlet portion (32) of the valve shaft (31) as the valve shaft (31) rotates, and a fluid channel (37) extending through the valve member (35). When the valve shaft (31) is rotated to a position where the radial slot (33) of the inlet portion (32) aligns with the fluid channel (37) of the valve member (35), air can flow through the valve member (35) and the valve shaft (31) through the valve (30). The aforementioned device (40) further, The air supply device (42) connected to the valve (30), A nozzle (43) is arranged to supply air pulses to one or both sides of the web (20) of the packaging material, A drive device (41) connected to the valve shaft (31) for rotating the valve shaft (31), Equipped with, The valve shaft (31) is rotated so that the radial slot (33) of the valve shaft (31) is in fluid communication with the fluid channel (37) of the valve member (35), so that air flows through the valve (30) via the valve member (35) and the valve shaft (31) (104). Method (100).

14. The web (20) of the packaging material comprises a number of sequentially arranged sections (21a to f) arranged to form a package, and at least a subset of the sections (21a to f) comprises positioning elements (23a to f), Step (106) of measuring when the positioning elements (23a to f) are passing the positioning element leader (45), The steps include (108) calculating the time it takes for a desired area of ​​the web (20) of the packaging material to pass through the valve (30) based on the output of the positioning element leader (45), The step (104) of rotating the valve shaft (31) is performed at the calculated time. The method according to claim 13.

15. The method according to claim 14, wherein the desired region is an opening device (22a to f) provided on the web (20) of the packaging material.

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