Heating device

Abstract

A heating device (18) for thermoforming a film (6), comprising: a first tool (30) provided with a first heating plate (42) mounted by means of a plurality of first spring elements (50a, 50b); and a second tool (32) provided with a second heating plate (46), the second tool being mounted by means of a plurality of second spring elements (52a, 52b, 52c). The spring elements (50, 52) of the plurality of first spring elements (50a, 50b) and the plurality of second spring elements (52a, 52b, 52c) are spaced apart from each other in at least one direction perpendicular to the spring axis (Xi).

Description

Technical Field

[0001] The present invention relates to a heating device for heating and forming a film, a packaging machine including the heating device, and a method for operating the packaging machine. Background Technology

[0002] Packaging machines known in the prior art for packaging products first mold cavities into a forming film, then fill the cavities with the product and seal them with a covering film. The resulting packaging is also called blister packaging, and the packaging machine is therefore called a blister machine. Such packaging machines may include a heating device to heat the forming film to a desired forming temperature before the forming device molds the cavity into the forming film. One type of heating device comprises two plate-like tools, each with a heating plate, through which the forming film is guided in a rhythmic manner. When the tools close, the heating plate contacts the forming film and heats it to the desired temperature. However, it is clear that the heating plates may have unevenness due to manufacturing and / or assembly. These unevennesses may be localized or, for example, curved openings in the edge areas of the heating plates, where gaps may form between the heating plates. Unevenness prevents the heating plates from establishing full contact with the forming film, which in turn leads to uneven heat transfer to the forming film. The resulting uneven temperature distribution in the molded film can adversely affect the subsequent molding process and the quality of the molded film and the molded cavity. For example, the molding temperature cannot be reliably reached throughout the entire format range. Summary of the Invention

[0003] The purpose of this invention is to provide a heating device for heating and forming films, which can achieve uniform and precise heating of the formed films in a simple and cost-effective manner.

[0004] According to one aspect of the present invention, a heating device for heating and forming a film includes a first tool and a second tool. The first tool includes a first mounting frame and a first heating plate, the first heating plate being mounted on the first mounting frame by a plurality of first spring elements. The second tool includes a second mounting frame and a second heating plate, the second heating plate being mounted on the second mounting frame by a plurality of second spring elements. Each of the plurality of first spring elements and the plurality of second spring elements has a spring axis and is spaced apart from each other in at least one direction perpendicular to the spring axis.

[0005] In this manner, a heating device is provided in which a first heating plate and a second heating plate are mounted via spaced-apart spring elements. When the first and second tools are closed, the spring forces of the multiple first spring elements and multiple second spring elements do not cancel each other out, but instead act on the heating plate, causing it to elastically deform. Due to this elastic deformation, the first and second heating plates adapt to each other, thereby compensating for unevenness and tolerances, and establishing full contact with the formed film. This facilitates uniform and precise heating of the formed film without significantly increasing the workload and cost of heating plate production and assembly.

[0006] Preferably, the formation and arrangement of the plurality of first spring elements and the plurality of second spring elements ensure that the first heating plate and / or the second heating plate undergo elastic deformation when the first tool and the second tool are in the closed state. Therefore, by appropriately selecting and arranging the spring elements, the aforementioned uniform and precise heating can be achieved very easily.

[0007] The construction and arrangement of the multiple first spring elements and multiple second spring elements depend on, for example, the stiffness of the first and second heating plates, and thus primarily on their materials and thicknesses. Those skilled in the art can select and position suitable spring elements to induce elastic deformation of the heating plates based on their construction without extensive experimentation.

[0008] Each of the plurality of first spring elements is preferably spaced apart from each of the plurality of second spring elements. In other words, all spring elements are spaced apart from each other in the direction perpendicular to their spring axes, and the spring axes of any pair of first and second spring elements are not coaxial. Thus, all the first and second spring elements work together to achieve the desired effect. The spring axes of all the spring elements in the first and second spring elements are preferably parallel to each other.

[0009] The first and second tools can be stacked one on top of the other, with the first tool serving as the upper mold and the second tool as the lower mold. The formed film extends horizontally between the first and second tools. However, the first and second tools can also be arranged side by side, so that the formed film extends substantially vertically or obliquely between the two tools under the action of the vertical component.

[0010] The first and second tools are preferably movable relative to each other along the stroke direction, particularly between an open and a closed state. In the open state, the forming film can be inserted into the intermediate space between the first and second heating plates and guided through them. In the closed state, the first and second heating plates contact the forming film disposed therebetween. The heating device includes at least one driving device for parallel movement of the first and / or second tools along the stroke direction. In a preferred embodiment, a first driving device is provided for parallel movement of the first tool along the stroke direction, while the second tool remains fixed. However, a first driving device for moving the first tool and a second driving device for moving the second tool may also be provided.

[0011] A conveying direction is defined within the heating device, along which the formed film can pass. The conveying direction is preferably perpendicular to the stroke direction. The transverse direction can be defined as perpendicular to both the conveying and stroke directions. The formed film extends substantially within a plane defined by the conveying and transverse directions. The spring elements of the plurality of first and second spring elements are preferably spaced apart from each other at least in the conveying and / or transverse directions.

[0012] Multiple first spring elements and multiple second spring elements preferably support a first heating plate and a second heating plate, enabling them to move along the spring axis. The spring axes of the multiple first and second spring elements are preferably arranged parallel to the stroke direction. When the first and second heating plates come into contact with each other during the receipt of the formed film, they can spring back. In a preferred embodiment, the first and second heating plates are only elastically mounted. The first and second heating plates can be respectively spaced apart from either the first or second mounting bracket to provide springback space for the heating plates and allow them to undergo elastic deformation.

[0013] The multiple first spring elements and multiple second spring elements are preferably arranged in a predetermined manner. This arrangement can be determined based on the expected unevenness or tolerance, or based on the required degree of elastic deformation of the heating plate. For example, in areas where greater unevenness is expected, more spring elements can be provided than in areas where less unevenness or no unevenness is expected. Alternatively, a uniform distribution scheme of the spring elements can be selected, for example, to achieve uniform elastic deformation of the heating plate.

[0014] To describe the arrangement of multiple first spring elements and multiple second spring elements, it is more advantageous to observe from a top view or by projecting onto a projection plane perpendicular to the spring axis.

[0015] In a preferred embodiment, the spring elements of the plurality of first spring elements and the plurality of second spring elements are arranged along at least one straight line, preferably along multiple straight lines. This straight line is preferably located within the projection plane. The spring axes of all spring elements arranged along a specific straight line intersect that straight line.

[0016] At least one straight line can be configured to be parallel to the conveying direction, parallel to the transverse direction, or inclined to the conveying direction. If multiple straight lines are provided, these straight lines are preferably parallel to each other. Spring elements arranged along the same straight line are preferably arranged at equal intervals, so that the spring force acts evenly on the heating plate, thereby ensuring uniform heating of the formed film. However, the spring elements can also be arranged at non-equal intervals.

[0017] In another embodiment, the spring elements of a plurality of first spring elements and a plurality of second spring elements are arranged along at least one circular line, preferably along multiple circular lines. This circular line is preferably located in the projection plane. The spring axes of all spring elements arranged on the respective circular lines intersect the circular line. If multiple circular lines are provided, they are preferably arranged concentrically. Spring elements arranged along the same circular line are preferably arranged at equal intervals. However, non-equal intervals are also possible.

[0018] Similarly, it is conceivable to combine the above different arrangements, such as a straight line arrangement with different directions of extension and / or a combination of a straight line and a circular line. Likewise, it is conceivable to arrange the spring elements of a plurality of first spring elements and the spring elements of a plurality of second spring elements along at least one line with different shapes, such as a curved, elliptical, or sinusoidal trajectory.

[0019] Generally, it is advantageous to alternate between the first and second spring elements. In this case, each second spring element will be adjacent to its corresponding first spring element, and vice versa. Particularly preferred is that, regardless of the line shape, one of the multiple first spring elements and one of the multiple second spring elements are arranged alternately along each line. With this arrangement, the first and second heating plates can achieve elastic deformation and full contact with the molded film, without requiring excessive deformation in any specific area. Instead, multiple relative deformations are generated, which can be easily achieved.

[0020] The plurality of first spring elements preferably comprises 2 to 30 first spring elements, more preferably 5 to 25 first spring elements, and even more preferably 10 to 20 first spring elements. The plurality of second spring elements preferably comprises 2 to 30 second spring elements, more preferably 5 to 25 second spring elements, and even more preferably 10 to 20 second spring elements. Obviously, for a conventional heating plate (especially in a blister pack machine), the above-mentioned number of spring elements can achieve sufficient elastic deformation, which can both compensate for the unevenness formed and ensure a flat contact with the formed film.

[0021] For the multiple first spring elements and multiple second spring elements, various spring elements and elastic elements known to those skilled in the art that can mount the first heating plate to the first mounting bracket and the second heating plate to the second mounting bracket can be used. For example, leaf springs, torsion springs (especially helical springs), disc springs, rubber springs, air springs, or gas compression springs can be selected. Preferably, the multiple first spring elements and multiple second spring elements can generate an elastic force parallel to the spring axis.

[0022] Typically, the multiple first spring elements and multiple second spring elements are preferably composed of compression springs. When both the multiple first spring elements and multiple second spring elements are composed of helical springs (especially made of stainless steel), a particularly simple and cost-effective structural solution can be achieved. For ease of installation of the heating plate, it is even more advantageous if the multiple first spring elements and multiple second spring elements can be compressed in a direction parallel to the spring axis (as shown in the aforementioned types of spring elements).

[0023] Furthermore, it has been clarified that when each of the plurality of first spring elements and the plurality of second spring elements reaches its maximum force, preferably between 5N and 25N, and more preferably between 10N and 20N, the desired elastic deformation can be achieved. The spring stiffness of each of the plurality of first spring elements and the plurality of second spring elements can be between 1N / mm and 10N / mm, and more preferably between 2N / mm and 5N / mm. Considering the degree of freedom of movement of the heating plate, sufficient spring force can thus be obtained.

[0024] To achieve optimal heat conduction to the molded film while ensuring flexible mounting, the first heating plate preferably includes at least one first heat transfer element for contacting the molded film, and at least one first heating device for heating the first heat transfer element; the second heating plate preferably includes a second heat transfer element for contacting the molded film, and at least one second heating device for heating the second heat transfer element.

[0025] At least one first heat transfer element and at least one second heat transfer element preferably both have a plate-like structure and a working surface, which faces the other of the first and second heat transfer elements. This design facilitates full contact between the first and second heat transfer elements and the molded film. The working surfaces of at least one first heat transfer element and at least one second heat transfer element together define the intermediate space between the first and second tools.

[0026] At least one first heating device is preferably disposed on the back side of at least one first heat transfer element, which is opposite to the working surface of at least one first heat transfer element and preferably in direct contact with at least one first heat transfer element. At least one second heating device is preferably disposed on the back side of at least one second heat transfer element, which is opposite to the working surface of at least one second heat transfer element and preferably in direct contact with at least one second heat transfer element. Therefore, the first heating device and the second heating device can be as close as possible to their respective heat transfer elements or working surfaces to achieve rapid and as lossless as possible heat transfer.

[0027] To achieve optimal thermal conductivity while maintaining good deformability, it is preferable that the at least one first heat transfer element and the at least one second heat transfer element comprise a metal plate. The metal plate is preferably made of aluminum or an aluminum alloy, but other metallic materials may also be used. The first and second heat transfer elements may also have a surface coating.

[0028] In a preferred embodiment, the thicknesses of at least one first heat transfer element and at least one second heat transfer element are respectively between 1 mm and 15 mm, more preferably between 2 mm and 10 mm, and even more preferably between 2 mm and 6 mm or between 2 mm and 4 mm. The thinner the thickness of at least one first heat transfer element and at least one second heat transfer element, the better the elastic deformation can be achieved by the spring element.

[0029] The first and second heating devices may respectively comprise mica sheet heating elements, silicone heating elements, or thick-film heating elements. Such elements are particularly suitable because they can provide sufficient heating power within limited installation space.

[0030] Furthermore, it is more advantageous when the first heating plate and / or the second heating plate comprises multiple segments. Specifically, in this case, the first and / or second heating plates can be physically divided into multiple segments. Particularly preferably, the first heating plate comprises multiple first heat transfer elements, and the second heating plate comprises multiple second heat transfer elements, with the number of each preferably corresponding to the number of segments. The segmented design reduces manufacturing tolerances and creates flexible and easily deformable heating plate segments. The multiple segments are preferably arranged front-to-back in the conveying direction.

[0031] In standard heating plates, especially in blister packaging machine applications, a segmented structure with 2 to 5, preferably 3 or 4, has proven to be most suitable. Each segment can typically be configured with 2 to 8 spring elements, preferably 4 to 5.

[0032] In the multiple segments of the first heating plate and / or the second heating plate, each segment may be provided with a first or second heating device. Alternatively, multiple heating devices may be arranged side by side in the transverse direction, for example, heating different width regions of the first heating plate and the second heating plate according to the width of the formed film.

[0033] Preferably, the first mounting bracket and the second mounting bracket are respectively provided with heat insulation layers near the first or second heating plate, or are made of heat insulation material in this area. This allows the generated heat to be transferred to the heat transfer element to the maximum extent possible, and thus act on the direction of the formed film.

[0034] Preferably, the first heating plate is elastically mounted only on the first mounting bracket, and the second heating plate is elastically mounted only on the second mounting bracket. For this purpose, the first mounting bracket may have multiple first recesses, wherein at least a portion of the spring elements of the multiple first spring elements is received in the corresponding first recess; the first heating plate may include multiple first receiving elements, wherein a spring element of the multiple first spring elements is mounted in a corresponding first receiving element. Correspondingly, the second mounting bracket may have multiple second recesses, wherein at least a portion of the spring elements of the multiple second spring elements is received in the corresponding second recess; the second heating plate may include multiple second receiving elements, wherein a spring element of the multiple second spring elements is mounted in a corresponding second receiving element. In this way, the spring-loaded mounting of the first and second heating plates can be achieved particularly simply and cost-effectively.

[0035] The receiving elements in the first and second receiving elements can be respectively composed of bolts or pins, and can be integrally formed with the corresponding heating plate or manufactured separately, and connected to the corresponding heating plate by means of, in particular, threaded connections. Preferably, multiple first receiving elements are arranged coaxially with multiple first recesses, and multiple second receiving elements are arranged coaxially with multiple second recesses. Multiple first spring elements and second spring elements can be directly mounted on the corresponding first or second receiving elements, or indirectly mounted through components such as sleeves.

[0036] According to one aspect of the invention, the packaging machine includes a heating device. All features of the heating device described herein in conjunction with the packaging machine can be directly applied to the heating device itself, and vice versa.

[0037] Particularly preferred is that the packaging machine is a blister forming machine for producing blister packaging. The forming film is preferably a plastic film, especially polypropylene. Since such films are relatively thick, precise heat input and sufficient heating are crucial.

[0038] Preferably, the packaging machine further includes a molding device for molding a cavity in the forming film—arranged downstream of the heating device along the conveying direction—and a filling device for filling the cavity with the product. The product may in particular be an ingestible medical or pharmaceutical product, food, or dietary supplement, such as tablets, capsules, sugar-coated pills, etc. Alternatively, the product may be a medical product or device, such as a syringe or injection pen, or a container, such as a bottle, vial, cartridge, etc. Of course, cosmetics or their containers, or consumables, may also be considered.

[0039] The packaging machine may also include a sealing device for closing the cavity, preferably designed as a sealing device that seals the capping film and the forming film together. The packaging machine may also include a separating device, particularly a stamping device, for separating multiple packages from the combination of the forming film and the capping film.

[0040] The preferred method of operating such a packaging machine includes the following steps: when the first tool and the second tool are in the open state, a section of the forming film is arranged between the first tool and the second tool; the first tool and the second tool are moved relative to each other to the closed state, in which the first tool and the second tool come into contact with the section of the forming film, and at the same time, the first heating plate and the second heating plate undergo elastic deformation; the first tool and the second tool are moved relative to each other back to the open state.

[0041] Because the advancement of the first and second tools induces elastic deformation in the first and second heating plates, they adapt to each other, compensating for unevenness and tolerances, and achieving full contact with the formed film. This not only helps to achieve uniform and precise heating of the formed film but also does not significantly increase the workload and cost of heating plate production and assembly.

[0042] Moving the first and second tools relative to each other to a closed state may include moving the first and / or second tools, particularly via a first or second drive mechanism, respectively. In a preferred embodiment, the first tool moves parallel to the stroke direction, while the second tool remains stationary. When the first heating plate contacts the section of the formed film and the second heating plate, both the first and second heating plates rebound. The first tool preferably continues to move parallel to the stroke direction, thereby generating a force that causes elastic deformation of the first and second heating plates. This achieves full contact with the formed film and heats it. The heating device can then be activated, preferably by moving the first tool parallel to the stroke direction.

[0043] All features of the heating device and packaging machine related to this method described herein can be applied to the heating device or the packaging machine, and vice versa. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of a packaging machine;

[0045] Figure 2 This is a schematic diagram of a heating device;

[0046] Figure 3 A schematic diagram of a component with a heating device in the on state;

[0047] Figure 4 for Figure 3 A schematic diagram of the heating device in the closed state;

[0048] Figure 5a -d is a schematic diagram of different variations of the exemplary arrangement of spring elements in a heating device. Detailed Implementation

[0049] Figure 1 A packaging machine 2 for producing package 4 is shown schematically in perspective view, and package 4 is shown in detail. The packaging machine 2 is preferably a blister packaging machine, and the package 4 produced is preferably a blister package. Each package 4 includes at least one product receiving cavity 8, which is in the form of a cavity formed in a forming film 6 for receiving product 10. Each product receiving cavity 8 preferably contains a single product 10, wherein product 10 may be an oral medical product, food, or dietary supplement, in the form of tablets, capsules, sugar-coated tablets, etc. A sealing film 12 can be sealed together with the forming film 6 to close the product receiving cavity 8.

[0050] In the illustrated embodiment of the packaging machine 2, the equipment is equipped with multiple processing stations or devices (see description below for details). However, it should be noted that the present invention is not limited to a specific packaging machine or blister packing machine.

[0051] The forming film 6 may be a thermoplastic film, wherein the product receiving cavity 8 is formed by a thermoforming process. The forming film 6 may be provided as a forming film roll 14, preferably wound on a storage roller 16. The packaging machine 2 includes a heating device 18 for heating the forming film 6 or the forming film roll 14, and a molding device 20 for molding the product receiving cavity 8 onto the forming film 6 or the forming film roll 14. The product 10 may be conveyed to and placed into the product receiving cavity 8 by a filling device 22. Subsequently, preferably by a sealing device 26 of the packaging machine 2, a cover film roll 24 is sealed to the forming film roll 14, thereby completing the closure of the product receiving cavity 8. The sealing film 12 is provided in the form of a cover film roll 24, preferably also wound on a storage roller (not shown), and conveyed from above to the forming film roll 14.

[0052] The packaging machine 2 also includes a separating device 28 for separating individual packages 4 from the forming film roll 14 or from a combination of the forming film roll 14 and the cover film roll 24. The separating device 28 is preferably designed as a stamping device. Downstream of the separating device 28, the packages 4 are in a separated state and can be conveyed to subsequent processing steps by a conveying device (not shown), such as a so-called pick-up device.

[0053] The formed film 6 or the formed film roll 14 passes through the packaging machine 2 along the conveying direction F, particularly the heating device 18. The transverse direction Q is defined as perpendicular to the conveying direction F. The plane defined by the conveying direction F and the transverse direction Q can also be called the working plane. The formed film roll 14 is arranged in this plane and processed by the various devices 18, 20, 22, 26, and 28 of the packaging machine 2.

[0054] Figure 2 A heating device 18, which can be used in packaging machine 2, is shown in more detail. This heating device 18 includes a first tool 30 and a second tool 32. Figure 2 In the heating device 18, the first tool 30 and the second tool 32 are in the open state, forming an intermediate space 34 between them. The forming film 6 is guided through the intermediate space 34 in the form of a forming film roll 14. The forming film roll 14 preferably moves in a rhythmic manner along the conveying direction F, such that a section of the forming film roll 14 is located within the heating device 18 in each cycle. The first tool 30 and the second tool 32 can move relative to each other in the stroke direction H between the open and closed states. In the closed state, the first tool 30 and the second tool 32 contact the forming film 6. The heating device 18 preferably includes drive devices 36 and 38 for driving either of the two tools 30 and 32, particularly the first drive device 36 for driving the first tool 30. As shown, the heating device 18 may also include the first drive device 36 for the first tool 30 and the second drive device 38 for the second tool 32, so that the first tool 30 and the second tool 32 move parallel to each other in the stroke direction H.

[0055] The first tool 30 includes a first mounting bracket 40 and a first heating plate 42 mounted thereon; the second tool 32 includes a second mounting bracket 44 and a second heating plate 46 mounted thereon. The first heating plate 42 and the second heating plate 46 together define an intermediate space 34 between the first tool 30 and the second tool 32, and face towards the molding film 6. When the first tool 30 and the second tool 32 are in a closed state, the first heating plate 42 contacts the top surface of the molding film 6, and the second heating plate 46 contacts the bottom surface of the molding film 6.

[0056] Figure 3 The first tool 30 and the second tool 32 are schematically shown in a side view. Heating plates 42 and 46 may typically have surface irregularities related to production and / or assembly, such as... Figure 3 The bending of heating plates 42 and 46 is schematically illustrated to illustrate this situation. For illustrative purposes, the deformation of heating plates 42 and 46 causing unevenness is exaggerated in the figure, but the actual deformation of each heating plate 42 and 46 may be between 0.1 mm and 1 mm, especially between 0.2 mm and 0.5 mm. This results in a gap of 0.5 mm to 1 mm between heating plates 42 and 46 in the closed state. Therefore, when the first tool 30 and the second tool 32 move to the closed position, the first heating plate 42 and the second heating plate 46 cannot achieve full contact with the molding film 6. The resulting uneven temperature distribution of the molding film 6 will negatively affect subsequent molding processes, as well as the quality of the molding film 6 and the formed product cavity 8.

[0057] Therefore, the first heating plate 42 is mounted on the first mounting bracket 40 via multiple first spring elements 50a and 50b, and the second heating plate 46 is mounted on the second mounting bracket 44 via multiple second spring elements 52a, 52b, and 52c. The spring elements of the multiple first spring elements 50a and 50b and the spring elements of the multiple second spring elements 52a, 52b, and 52c are aligned along a line perpendicular to their spring axis X. i They are arranged at intervals in the direction of the spring axis X. i The direction of the spring axis X is preferably parallel to the plane defined by the conveying direction F and the transverse direction Q. Therefore, the spring axes X of adjacent spring elements (50a, 50b, 52a, 52b, 52c) are... i They are arranged at intervals in the conveying direction F and / or the transverse direction Q, as shown by the distance D between the spring shaft X1 of the first spring element 50a and the spring shaft X2 of the second spring element 52a in the figure.

[0058] This staggered arrangement ensures that the elastic forces of the multiple first spring elements 50a, 50b and the multiple second spring elements 52a, 52b, 52c do not cancel each other out, but instead cause the first heating plate 42 and the second heating plate 46 to deform. The multiple first spring elements 50a, 50b and the multiple second spring elements 52a, 52b, 52c are preferably formed and arranged in such a way that when the first tool 30 and the second tool 32 are in a closed state, the first heating plate 42 and the second heating plate 46 undergo elastic deformation (e.g., ...). Figure 4 (As shown in the illustration). For ease of explanation, Figure 4 The article also exaggerated the deformation state of heating plates 42 and 46.

[0059] It is evident that, although the first heating plate 42 and the second heating plate 46 have an unevenness issue when the first tool 30 and the second tool 32 are in the open state (see...), Figure 3 However, in the closed state (see...) Figure 4 It can still achieve full contact with the molded film 6, thereby enabling directional and uniform heat transfer to the molded film 6.

[0060] like Figure 3 and Figure 4 As shown, each of the multiple first spring elements 50a and 50b is preferably staggered with each of the multiple second spring elements 52a, 52b and 52c, and any pair of first spring elements 50a and 50b and second spring elements 52a, 52b and 52c are not arranged coaxially, thereby ensuring that all spring elements can effectively participate in the expected deformation effect.

[0061] The plurality of first spring elements 50a, 50b and the plurality of second spring elements 52a, 52b, 52c are preferably compression springs, which can move along their respective spring axes X. i The parallel direction is compressed, supporting the first heating plate 42 and the second heating plate 46, allowing them to move in a direction parallel to the stroke direction H. Therefore, the spring axis X... i Preferably, it should be parallel to the stroke direction H.

[0062] like Figure 3 and Figure 4 As further shown, it is generally advantageous when the first spring elements 50a, 50b and the second spring elements 52a, 52b, 52c are always arranged alternately in the conveying direction F and / or the lateral direction Q. Figure 5a -d further describes a more advantageous arrangement of the plurality of first spring elements 50a, 50b and the plurality of second spring elements 52a, 52b, 52c.

[0063] To ensure that the first heating plate 42 and the second heating plate 46 can deform sufficiently and achieve optimal heat transfer to the molded film 6, the first heating plate 42 preferably includes a first heat transfer element 54 for transferring heat to the molded film 6, and a first heating device 56 for heating the first heat transfer element 54. Correspondingly, the second heating plate 46 preferably includes a second heat transfer element 58 for transferring heat to the molded film 6, and a second heating device 60 for heating the second heat transfer element 58.

[0064] The first heat transfer element 54 and the second heat transfer element 58 preferably adopt a basic plate-like structure so as to make flat contact with the molded film 6, and can be made of metal plate, especially aluminum or aluminum alloy. The surfaces of the first heat transfer element 54 and the second heat transfer element 58 facing the molded film 6 respectively constitute the working surfaces 54a and 58a of the heat transfer elements 54 and 58.

[0065] The first heating device 56 can be disposed on the back side of the first heat transfer element 54, opposite to and in direct contact with the working surface 54a of the first heat transfer element 54. The second heating device 60 can be disposed on the back side of the second heat transfer element 58, opposite to and in contact with the working surface 58a of the second heat transfer element 58. The first heating device 56 and the second heating device 60 preferably employ a mica plate heating element structure. With this design, the first heat transfer element 54 and the second heat transfer element 58 can maintain sufficient thinness to achieve elastic deformation, while also receiving uniform heating and efficiently transferring heat to the formed thin film 6.

[0066] Furthermore, when the first heating plate 42 and the second heating plate 46 each comprise multiple segments 421, 422, 423, 461, 462, and 463, further beneficial effects are achieved. Figure 2As shown, the first heating plate 42 comprises three segments 421, 422, and 423, and the second heating plate 46 comprises three segments 461, 462, and 463, which are arranged sequentially along the conveying direction F. At this time, the first heating plate 42 and the second heating plate 46 are physically separated, such that the first heating plate 42 comprises multiple first heat transfer elements 54 and multiple first heating devices 56; the second heating plate 46 comprises multiple second heat transfer elements 58 and multiple second heating devices 60. Each pair of heat transfer elements 54, 58 and heating devices 56, 60 can respectively constitute a segment of the first heating plate 42 or the second heating plate 46. Each of the multiple segments 421, 422, 423, 461, 462, and 463 is mounted by spring elements, wherein each segment is preferably configured with 4 to 5 spring elements.

[0067] The following text will be based on the spring element in the direction perpendicular to the spring axis X. i A top view or projection drawing on the projection plane, refer to Figure 5a -d describes different arrangements of the multiple first spring elements 50 and the multiple second spring elements 52.

[0068] like Figure 5a and Figure 5b In the illustrated embodiment, multiple first spring elements 50a, 50b, 50c, and 50d, and multiple second spring elements 52a, 52b, 52c, and 52d, are arranged along multiple straight lines 62a and 62b. Preferably, as shown, the first spring elements 50a, 50b, 50c, and 50d, and the second spring elements 52a, 52b, 52c, and 52d are always arranged alternately along their respective straight lines 62a and 62b. The multiple lines 62a and 62b can be arranged parallel to each other and parallel to the conveying direction F (see figure). Figure 5a ), parallel to the transverse direction Q (not shown) or inclined to the conveying direction F (see Figure 5b In addition, lines can be curved rather than straight.

[0069] like Figure 5c In the illustrated embodiment, the spring elements 50a, 50b, 50c, and 50d of the plurality of first spring elements and the spring elements 52a, 52b, 52c, and 52d of the plurality of second spring elements are arranged along multiple circular lines 64a and 64b. Preferably, the first spring elements 50a, 50b, 50c, and 50d and the second spring elements 52a, 52b, 52c, and 52d are always arranged alternately along their respective lines 64a and 64b. As shown, the multiple lines 64a and 64b can be arranged concentrically. Alternatively, the lines can also be elliptical rather than circular, or other shapes.

[0070] at last, Figure 5dOne embodiment is shown in which a plurality of first spring elements 50a, 50b, 50c, 50d and a plurality of second spring elements 52a, 52b, 52c, 52d are arranged irregularly. Due to the arbitrary arrangement of the spring elements, uneven areas of the heating plate caused by manufacturing defects or loads can be individually arranged to achieve specific deformation requirements. This allows for further arbitrary deformation, ensuring that the heating plates 42, 46 can be flatly bonded to the molded film 6 under different conditions.

[0071] This invention provides a heating device, a packaging machine including the heating device, and a method for operating the packaging machine. A heating plate is elastically mounted using spring elements, causing the heating plate to undergo elastic deformation. These spring elements are arranged spaced apart from each other, ensuring smooth contact between the heating plate and the forming film even if the heating plate is uneven, thereby achieving optimal heat conduction. Other embodiments will be clearly understood by those skilled in the art based on the detailed description of the preferred exemplary embodiments contained herein.

Claims

1. A heating device (18) for heating and forming a thin film (6), characterized in that, The heating device (18) includes: A first tool (30) comprising a first mounting bracket (40) and a first heating plate (42), the first heating plate (42) being mounted on the first mounting bracket (40) by a plurality of first spring elements (50a, 50b); and The second tool (32) includes a second mounting bracket (44) and a second heating plate (46), the second heating plate (46) being mounted on the second mounting bracket (44) by a plurality of second spring elements (52a, 52b, 52c); Among them, the spring element (50, 52) in the plurality of first spring elements (50a, 50b) and the plurality of second spring elements (52a, 52b, 52c) each has a spring axis (X). i ), and at least one of them is perpendicular to the spring axis (X). i They are spaced apart from each other in the vertical direction.

2. The heating device (18) according to claim 1, characterized in that: The formation and arrangement of the plurality of first spring elements (50a, 50b) and the plurality of second spring elements (52a, 52b, 52c) are such that the first heating plate (42) and the second heating plate (46) undergo elastic deformation when the first tool and the second tool (30, 32) are in the closed state.

3. The heating device (18) according to claim 1, characterized in that: The plurality of first spring elements (50a, 50b) and the plurality of second spring elements (52a, 52b, 52c) are arranged along at least one straight line (62a, 62b).

4. The heating device (18) according to claim 3, characterized in that: A first spring element (50) of the plurality of first spring elements (50a, 50b) and a second spring element (52) of the plurality of second spring elements (52a, 52b, 52c) are arranged alternately along the at least one straight line (62a, 62b).

5. The heating device (18) according to claim 1, characterized in that: The plurality of first spring elements (50a, 50b) and the plurality of second spring elements (52a, 52b, 52c) are arranged along at least one circular line (64a, 64b).

6. The heating device (18) according to claim 5, characterized in that: A first spring element (50) of the plurality of first spring elements (50a, 50b) and a second spring element (52) of the plurality of second spring elements (52a, 52b, 52c) are arranged alternately along the at least one circular line (64a, 64b).

7. The heating device (18) according to claim 1, characterized in that: The plurality of first spring elements (50a, 50b) includes 2 to 30 first spring elements (50), and the plurality of second spring elements (52a, 52b, 52c) includes 2 to 30 second spring elements (52).

8. The heating device (18) according to claim 1, characterized in that: The plurality of first spring elements (50a, 50b) and the plurality of second spring elements (52a, 52b, 52c) are composed of compression springs, particularly helical springs.

9. The heating device (18) according to claim 1, characterized in that: The first heating plate (42) includes: at least one first heat transfer element (54) for contacting the molded film (6) and at least one first heating device (56) for heating the at least one first heat transfer element (54); The second heating plate (46) includes at least one second heat transfer element (58) for contacting the molded film (6) and at least one second heating device (60) for heating the at least one second heat transfer element (58).

10. The heating device (18) according to claim 9, characterized in that: The at least one first heat transfer element (54) and the at least one second heat transfer element (58) comprise metal plates.

11. The heating device (18) according to claim 9, characterized in that: The at least one first heat transfer element (54) and the at least one second heat transfer element (58) each have a thickness between 1 mm and 15 mm, preferably between 2 mm and 10 mm.

12. The heating device (18) according to claim 1, characterized in that: The first heating plate (42) and the second heating plate (46) include multiple segments (421, 422, 423, 461, 462, 463).

13. The heating device (18) according to claim 1, characterized in that: The first mounting bracket (40) has a plurality of first recesses, and the spring element (50) of the plurality of first spring elements (50a, 50b) is received in the corresponding first recess; and The first heating plate (42) includes a plurality of first receiving elements, and the spring element (50) of the plurality of first spring elements (50a, 50b) is installed in the corresponding first receiving element.

14. The heating device (18) according to claim 1, characterized in that: The second mounting bracket (44) has a plurality of second recesses, and spring element (52) of the plurality of second spring elements (52a, 52b, 52c) is received in the corresponding second recess; and The second heating plate (46) includes a plurality of second receiving elements, wherein the spring element (52) of the plurality of second spring elements (52a, 52b, 52c) is installed in the corresponding second receiving element.

15. A packaging machine (2), characterized in that, Includes the heating device (18) according to claim 1.

16. A method for operating the packaging machine (2) according to claim 15, characterized in that, Includes the following steps: When the first tool (30) and the second tool (32) are in the open state, a section of the molded film (6) is arranged between the first tool (30) and the second tool (32); The first tool (30) and the second tool (32) are moved relative to each other to a closed state. In this state, the first tool (30) and the second tool (32) come into contact with this section of the molded film (6), wherein the first heating plate (42) and the second heating plate (46) undergo elastic deformation. The first tool (30) and the second tool (32) are moved back to the open state.

Images