Inducer and ultrasonic horn

Abstract

To provide an anvil for improving transverse seal of a package.SOLUTION: An anvil 400, for forming transverse seal in a sleeve-like portion of a packaging material to hold a liquid product, includes a main surface 402 that, in operation, confronts a tube and a ridge 404 that is provided in the main surface. In the anvil 400, the ridge includes a first section 406 and a second section, in which the first section of the ridge is placed below the second sections 408a, 408b so that, in operation, stresses in the packaging material formed by hydrostatic pressure formed by a liquid product are to be shifted from a first portion of the sleeve-like portion placed above the first section of the ridge up to a second portion placed above the second section.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to packaging technology, and more particularly to anvils, transverse sealing systems, roll-fed fillers, blank-fed fillers, and methods for producing packages. [Background technology]

[0002] Roll-fed carton fillers, such as the Tetra Brik® packaging machine marketed by Tetra Pak, are currently used to package liquid foods such as milk. So-called blank-fed fillers are also known. Instead of continuously providing the liquid food product into a tube that is formed into a package, blank-fed fillers are fed with so-called blanks, i.e., sleeves of packaging material. During production, the blanks are closed at one end, filled with the product, and then closed at the other end. Examples of such machines are the Tetra Rex® machine and the Tetra Recart® machine, both marketed by Tetra Pak®.

[0003] In both types of filling machines, a longitudinal seal and a transverse seal are created. In a roll-feed filling machine, a longitudinal seal is created as the tube is formed, and a transverse seal is created at the lower end of the tube so that a package can be formed from the tube. In a blank-feeding machine, the longitudinal seal is often pre-made, i.e., the blank provided to the machine already has a longitudinal seal created. A transverse seal is often created when closing an end before filling, i.e., forming the bottom or top, and when closing the other end. Therefore, in a blank-feeding machine, there may be two modules that create the transverse seal. In contrast, in a roll-feeding filling machine, the two transverse seals are often created simultaneously, i.e., the bottom is formed on one package and the top is formed on the subsequent package. Packages are continuously provided from the tube by cutting between the two transverse seals.

[0004] However, other alternatives are possible. For example, in a carton bottle machine, such as a Tetra Top® machine, the packaging material is roll-fed so that the packaging material is provided via a reel. In that machine, the packaging material is cut and a longitudinal seal is created as a blank is formed. In a first station, a plastic top section is injection molded onto the blank, and in a second station, after product filling, a transverse seal is created to provide the bottom of the package.

[0005] When forming a transverse seal, the packaging material is generally heated to melt the plastic layer, and the transverse seal is formed by pressing two sides of the packaging material toward each other. Heat can be generated by inducing an electric current in the aluminum foil of the packaging material using an inductor or by providing ultrasonic waves using an ultrasonic horn. An anvil is placed on the opposite side of the inductor or ultrasonic horn to provide the pressure.

[0006] Different anvil designs have been developed to provide reliable transverse seal formation. According to one anvil design, one or several ridges are provided on the contact surface of the anvil, i.e., the surface facing the packaging material. By having ridges, pressure is applied in a more controlled manner, which also results in a more reliable transverse seal. Another option is to have a flat anvil and ridges on the ultrasonic horn.

[0007] While the anvils create a reliable lateral seal, there is nevertheless room for improvement. A more reliable lateral seal would result in fewer package leaks, i.e., fewer quality complaints, and the package would be able to withstand more rough handling, which can be a challenge during distribution. In addition to being more reliable, i.e., ensuring that the tube or sleeve is properly closed, improved anvils would also increase the speed of the filling machine and require less energy to create the lateral seal. Summary of the Invention [Problem to be solved by the invention]

[0008] It is an object of the present invention to at least partially overcome one or more of the above-identified limitations of the prior art. In particular, it is an object to provide an anvil that improves the transverse sealing of packages. [Means for solving the problem]

[0009] According to a first aspect, there is provided an anvil for forming a transverse seal in a sleeve-like portion of a packaging material holding a liquid product, the anvil including a main surface that faces a tube during operation and a ridge provided on the main surface, the ridge including a first section and a second section, the first section of the ridge being positioned below the second section so that during operation stress in the packaging material formed by hydrostatic pressure created by the liquid product is shifted from the first portion of the sleeve-like portion positioned above the first section of the ridge to the second portion positioned above the second section.

[0010] The sleeve-like portion may have a longitudinal seal created in a first portion of the portion.

[0011] The second section may include a first peripheral subsection and a second peripheral subsection, and the second section is a central section located between the first peripheral subsection and the second peripheral subsection.

[0012] The packaging material may comprise a plastic layer comprising a polymer, and the vertical distance between the first section and the second section may be set relative to the properties of the polymer and / or the thickness of the plastic layer and / or the stiffness properties of the packaging material.

[0013] A continuous transition from the first section to the second section may be provided so that stresses in the packaging material are reduced.

[0014] The packaging material may be a carton-based packaging material.

[0015] According to a second aspect, there is provided a lateral sealing system comprising first and second anvils according to the first aspect, wherein the first anvil is placed above the second anvil during operation and the second anvil is placed upside down relative to the first anvil such that a first section of the ridge of the first anvil is placed below a second section of the ridge of the first anvil and the first section of the ridge of the second anvil is placed above a second section of the ridge of the second anvil.

[0016] The system may further include an ultrasonic horn positioned on opposite sides of the first and second anvils such that the part is positioned between the ultrasonic horn and the first and second anvils.

[0017] According to a third aspect, there is provided a roll-fed filler machine comprising a lateral sealing system according to the second aspect, a package rotating device located downstream of the lateral sealing system and configured to rotate upside down a package formed by the lateral sealing system, and a folding device configured to fold the package into a final shape.

[0018] According to a fourth aspect, there is provided a blank feed and fill machine comprising a lateral sealing station for closing an end of a portion of packaging material, and a filling station for filling the portion with product, the lateral sealing station comprising an anvil according to the first aspect.

[0019] According to a fifth aspect, there is provided a method for producing a package, the method comprising providing a sleeve-shaped portion of packaging material and sealing the portion laterally, the anvil having a major surface facing the portion during operation and a ridge provided on the major surface, the ridge comprising a first section and a second section, the first section being positioned below the second section during operation such that stresses in the packaging material formed by hydrostatic pressure of the liquid product are shifted from a first portion of the portion positioned above the first section of the ridge to a second portion positioned above the second section.

[0020] The portion may have a longitudinal seal created in a first portion of the portion.

[0021] The packaging material may comprise a plastic layer comprising a polymer, the vertical distance between the first section and the second section being set relative to the properties of the polymer and / or the thickness of the plastic layer and / or the stiffness of the packaging material.

[0022] A continuous transition from the first section to the second section may be provided so that stresses in the packaging material are reduced.

[0023] The packaging material may be a carton-based packaging material.

[0024] Further objects, features, aspects, and advantages of the present invention will become apparent from the following detailed description and drawings. Furthermore, it should be understood that features and advantages described in connection with one of the above-described aspects also apply to the other aspects, unless otherwise specified. Similarly, it should be understood that features and advantages described in connection with the examples also apply to the above-described aspects, unless otherwise specified. Yet another aspect of the present invention has a flat anvil and ultrasonic horn or inducer with ridges that match the anvil design described, which achieves the same effect.

[0025] Embodiments of the present invention will now be described, by way of example, with reference to the accompanying schematic drawings, in which: [Brief explanation of the drawings]

[0026] [Figure 1] 1 shows a roll-fed filling machine. [Figure 2] 1 shows a general view of a blank feed and filler machine. [Figure 3] 1 shows a carton bottle filling machine in its entirety. [Figure 4] 1 shows a front view of an anvil according to a first embodiment. [Figure 5] FIG. 10 shows a front view of an anvil according to a second embodiment. [Figure 6] 1 shows an example of a transverse seal created by a flat ridged anvil. [Figure 7] An example of a transverse seal made by the anvil shown in FIG. 4 is shown. [Figure 8a-b] 5 shows a lateral sealing system including two anvils as shown in FIG. 4. [Figure 9] 1 is a flow chart illustrating steps in a method for producing a package. DETAILED DESCRIPTION OF THE INVENTION

[0027] FIG. 1 shows, by way of example, a roll-fed carton filling machine 100. Packaging material 102, provided on a reel, is fed from the reel and formed into a tube 104, or more generally, a sleeve-like section. A liquid product is filled into the tube 104 via a valve 106 and a pipe 108. In a transverse sealing system 110, a transverse seal is made, and the lower end of the tube 104 is cut to form a package 112. After the transverse seal is made, the package 112 is rotated using a package rotating device 114, after which the package 112 may be folded into its final shape using a folding device 116. This general concept may be implemented in a variety of ways, and the example shown in FIG. 1 is only one example.

[0028] Roll-fed fillers have many advantages, one of which is that they are fast and cost-effective. However, when relatively small batches are produced, e.g., 5000 packages, it may be worth considering a blank-fed filler 200, generally as shown in FIG. 2.

[0029] Unlike the roll-fed filler 100 shown in FIG. 1, it is well known that blank-fed fillers are divided into different stations, and packages are transported between them on a conveyor belt. For example, as shown in FIG. 2, blank 202a, or more generally, a sleeve-like portion, folded flat at this stage, is fed to a first transverse sealing station 204, where a first end of blank 202a is closed with a transverse seal. Blank 202b, whose first end is closed at this stage, is then fed to a filling station 206, where blank 202b is filled with product. Blank 202c, whose first end is closed and whose product is filled at this stage, is then fed to a second transverse sealing station 208, where a second end of blank 202c is closed, resulting in blank 202d, which is filled with product and closed at both ends. In a further station located downstream, not shown, the blank 202d is folded into a package and may also be provided with, for example, a best before date, using a printing machine.

[0030] Rather than a lateral sealing system as shown in FIG. 1 in which two lateral seals are made simultaneously so that the tube 104 remains closed at its lower end despite certain sections being cut and formed into packages, the first and second lateral sealing stations 204, 206 are often designed to perform one lateral seal at a time.

[0031] FIG. 3 generally illustrates, by way of example, a so-called carton bottle machine 300. As with the blank-feed-and-fill machine 200 illustrated in FIG. 2, the carton bottle filling machine 300 includes different stations. Blank 302a, which is folded flat at this stage, is fed to a forming station 304, where a plastic top section is molded onto blank 302, forming blank 302b, which is closed at one end by the top section. Blank 302b may then be filled with product at filling station 306. Blank 302c, which is closed at one end by the top section and filled with product at this stage, is then fed to a transverse sealing station 308, where the other end of blank 302c is closed by creating a transverse seal, thereby forming blank 302d, which is closed at both ends and filled with product. Although not shown, further stations may be provided downstream, for example for folding blank 302d into a package and rotating the package.

[0032] In other words, in the carton bottle machine, the first transverse sealing station 204 in the blank feed and fill machine 200 shown in Figure 2 is replaced by a forming station 304. However, what is common to both machines, i.e., the blank feed machine 200 shown in Figure 2 and the carton bottle machine 300 shown in Figure 3, is that the transverse sealing station is used to close one end, or more generally, the sleeve-like portion, of the blank.

[0033] 4 illustrates, by way of example, an anvil 400 used to generate a transverse seal in a sleeve-like portion, such as the tube 104 shown in FIG. 1 or the blanks 202a-d, 302a-d shown in FIGS. 2 and 3, respectively. The major surface 402, configured to face the packaging material 104 during operation, may include a ridge 404, i.e., an elongated protrusion. The ridge 404 may include two sections: a first section 406 configured to abut a central portion of the tube 104 or blank 202a-d, 302a-d, and a second section 408a, 408b divided into first and second peripheral subsections 408a, 408b configured to abut peripheral portions of the tube or blank, commonly referred to as the sleeve-like portion. The sleeve-like portion and the anvil may be held together such that the longitudinal seal of the sleeve-like portion abuts the first section 406 when forming the transverse seal.

[0034] As shown, the first section 406 may be positioned below the second sections 408 a, 408 b. The advantage of this is that during operation, stresses in the packaging material 102, more particularly the packaging material forming the transverse seals, also formed by hydrostatic pressure created by the product, are shifted from a first portion positioned above the first section 406 to a second portion of the sleeve-like portion positioned above the second sections 408 a, 408 b. In this way, stiffness in the packaging material 102 is used to mitigate, or at least reduce, the risk of weaknesses forming in the intersection areas where the longitudinal and transverse seals meet.

[0035] To determine the vertical distance VD between the first section 406 and the second sections 408a, 408b, the properties of the packaging material 102 may be taken into account. For example, if a carton-based packaging material is used and includes a plastic layer, i.e., a polymer-based layer, the properties of the polymer may be taken into account. Additionally, the thickness of the plastic layer may be taken into account. Additionally, the stiffness of the packaging material, e.g., the thickness of the carton layer of the packaging material, may be taken into account.

[0036] As shown, the transition from the first section 406 to the second sections 408a, 408b can be continuous, i.e., there is no step change. The advantage of this is that the risk of creating stresses in the packaging material is reduced, which in turn creates a more reliable lateral seal.

[0037] The anvil 400 shown in FIG. 4 proves useful in the roll-fed filler 100 shown in FIG. 1 because, with roll-fed fillers, the longitudinal seal is often centered over the transverse seals.

[0038] FIG. 5 also shows, by way of example, another anvil 500. Like the anvil 400 shown in FIG. 4, the anvil 500 shown in FIG. 5 includes a major surface 502 having ridges 504. Furthermore, the ridges 504 are divided into a first section 506 and a second section 508, with the first section 506 positioned below the second section 508. Unlike the anvil 400 shown in FIG. 4, the first section 506 is not centrally positioned facing the central section of the sleeve-like portion, but instead is positioned facing the peripheral sections. This is advantageous in a sleeve-like filling machine, such as the sleeve-like filling machine 200 shown in FIG. 2, where a longitudinal seal can be created in the peripheral sections of the blanks 202a-d.

[0039] In Figure 6, a transverse seal 600 is shown as an example. The illustrated transverse seal is created by using a flat, ridged anvil, i.e., an anvil in which both sections are at the same horizontal level, rather than the first section below the second. As indicated by the arrows, stress in the packaging material 104 is higher in the cross region 602 where the longitudinal seal meets the transverse seal. One reason for the higher stress in this region is that there are three layers of packaging material in this region, compared to two layers outside of that region.

[0040] FIG. 7 shows another transverse seal 700. This transverse seal 700 is formed using the anvil 400 shown in FIG. 4. As indicated by the arrows, in a first portion 702 corresponding to the first section 406, stress is lower than in first and second peripheral subportions 704a, 704b corresponding to the first and second peripheral subsections 408a, 408b. In a cross region 706 where the longitudinal seal and the transverse seal meet, stress is therefore lower than in the cross region 602 in the transverse seal 600 shown in FIG. 6. By having a sloped curvature, i.e., a continuous transition, between the first section 406 and the sections 408a, 408b, stress in the corner regions 708a, 708b can also be reduced.

[0041] Figures 8a and 8b show in more detail the lateral sealing system 110 shown in Figure 1. Figure 8a shows a side view of a cross section of the anvil, and Figure 8b shows a front view.

[0042] As mentioned above, in the roll-fed fill machine 100 shown in Figure 1, the two transverse seals may be made simultaneously. This may be achieved by having two anvils 802a, 802b spaced apart so that a slit 804 is formed between the two anvils. Having this slit 804 provides for a knife 806 to be used to cut the tube 104 after the transverse seals are made. An ultrasonic horn 808, or other device that generates heat to melt the plastic layer in the packaging material, may be provided on the same side as the knife 806.

[0043] As shown, the two anvils 802a, 802b may be positioned so that they are oriented in opposite directions, i.e., the first anvil 802a is positioned with its first section below the second section of the ridge, and the second anvil 802b is positioned with its first section above the second section, with the advantage that after the transverse seal is created, the stresses created by hydrostatic pressure are reduced regardless of how the package is rotated.

[0044] Figure 9 is a flow chart illustrating the steps of a method 900. In a first step 902, a sleeved section 104 is provided. This can be accomplished by feeding the tube 104 to the transverse sealing system 110 in the roll-feed filling machine 100, or by transporting the blanks 202a-d, 302a-d to either one of the transverse sealing stations of the blank feeder 200 shown in Figure 2 or the carton bottle machine 300 shown in Figure 3. In a second step 904, the section 104 is transversely sealed.

[0045] It should be understood that expressions such as "lower" or "upper" refer to typical situations in which the device or method is applied, and therefore these expressions should be interpreted broadly unless otherwise specified. Furthermore, those skilled in the art will understand that orientation of, for example, a tube is done to ensure that the product is kept in place and that the sealing principle is not the same depending on the orientation.

[0046] Although the anvil has been described as including first and second sections positioned at different levels to reduce tension in the packaging material forming the transverse seal, it is also possible to have ultrasonic horns or inductors adapted to provide heating at different levels corresponding to the first and second sections, so that the same effect can be achieved even if the anvil is flat. Furthermore, combinations, i.e., anvils with first and second sections as described above, and ultrasonic horns or inductors that provide heating at different levels, can also be used.

[0047] From the above description, although various embodiments of the present invention have been described and illustrated, the present invention is not limited thereto and may be provided in other ways within the scope of the subject matter defined in the following claims.

Claims

1. An anvil (400, 500) for forming a transverse seal (700) in a sleeve-shaped portion (104) of a packaging material (102) holding a liquid product, said anvil (400, 500) comprising: a major surface (402, 502) that faces the tube (104) during operation; and Ridges (404, 504) provided on the main surfaces (402, 502) Including, the ridge (404, 504) includes a first section (406, 506) and a second section (208a, 208b, 508); The first sections (406, 506) of the ridges (404, 504) are positioned below the second sections (408a, 408b, 508) so that during operation, stress in the packaging material (102) created by hydrostatic pressure created by the liquid product is shifted from a first portion (702) of the sleeve-like portion (104) positioned above the first sections (406, 506) of the ridges to a second portion (704a, 704b) positioned above the second sections (408a, 408b, 508).

2. The anvil of claim 1, wherein the sleeve-like portion has a longitudinal seal (706) created in the first portion (702) of the portion (104).

3. 3. The anvil of claim 1, wherein the second section includes a first peripheral subsection and a second peripheral subsection, and the second section is a central section located between the first peripheral subsection and the second peripheral subsection.

4. 4. The anvil of claim 1, wherein the packaging material (102) comprises a plastic layer including a polymer, and wherein a vertical distance (VD) between the first section (406, 506) and the second section (208a, 208b, 508) is set relative to properties of the polymer and / or a thickness of the plastic layer and / or stiffness properties of the packaging material (102).

5. The anvil of any one of claims 1 to 4, wherein a continuous transition from the first section (406, 506) to the second section (408a, 408b, 508) is provided to reduce stress in the packaging material (102).

6. The anvil according to any one of claims 1 to 5, wherein the packaging material is a carton-based packaging material.

7. 7. A transverse sealing system (110) comprising first and second anvils (802a, 802b) according to claim 1, wherein the first anvil (802a) is placed above the second anvil (802b) during operation, and the second anvil (802b) is placed upside down relative to the first anvil (802a), so that the first section (406, 506) of the ridge (404, 504) of the first anvil (802a) is in contact with the first section (406, 506) of the ridge (404, 504) of the first anvil (802a). A lateral sealing system (110) configured such that the first section (406, 506) of the ridge (404, 504) of the first anvil (802a) is positioned below the second section (408a, 408b, 508) of the ridge (404, 504) of the second anvil (802b) and the first section (406, 506) of the ridge (404, 504) of the second anvil (802b) is positioned above the second section (408a, 408b, 508) of the ridge (404, 504) of the second anvil (802b).

8. 8. The lateral sealing system (110) of claim 7, further comprising an ultrasonic horn (808) disposed on an opposing side of the first and second anvils (802a, 802b), such that the portion (104) is positioned between the ultrasonic horn (808) and the first and second anvils (802a, 802b).

9. A lateral sealing system (110) according to claim 7 or 8, a package rotating device (114) located downstream of the transverse sealing system (110) and configured to rotate the package (112) formed by the transverse sealing system upside down; and a folding device (116) configured to fold the package into its final shape; A roll-fed filling machine (100) comprising:

10. A blank feed and filler (200), a transverse sealing station (204, 208, 308) for closing the ends of said portion (104) of packaging material; and a filling station (206, 306) for filling said portion (104) with product; Includes A blank feeding and filling machine (200) wherein the transverse sealing station (204, 208, 308) comprises an anvil according to any one of claims 1 to 6.

11. A method (900) for producing a package, said method comprising: Providing (902) a sleeve-like portion (104) of a packaging material (102); Laterally sealing (904) said portion (104). Including, The anvil (400, 500) includes a major surface (402, 502) that faces the portion (104) during operation, and a ridge (404, 504) provided on the major surface (402, 502), the ridge (404, 504) including a first section (406, 506) and a second section (408a, 408b, 508), and during operation, the first section (406, 506) is positioned below the second section (408a, 408b, 508), A method (900) in which stress in the packaging material (102) formed by the hydrostatic pressure of the liquid product is shifted from a first portion (702) of the portion located above the first section (406, 506) of the ridge to a second portion (704a, 704b) located above the second section (408a, 408b, 508).

12. The method of claim 11, wherein the portion has a longitudinal seal (706) created in the first portion (702) of the portion (104).

13. 13. The method of claim 11 or 12, wherein the packaging material (104) comprises a plastic layer containing a polymer, and the vertical distance (VD) between the first section (406, 506) and the second section (408a, 408b, 508) is set relative to the properties of the polymer and / or the thickness of the plastic layer and / or the stiffness of the packaging material (102).

14. The method of any one of claims 11 to 13, wherein a continuous transition from the first section (406, 506) to the second section (408a, 408b, 508) is provided such that stresses in the packaging material (104) are reduced.

15. The method according to any one of claims 11 to 14, wherein the packaging material is a carton-based packaging material.

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