Spacers for a lamination system

Abstract

A spacing device (100) for a system for laminating a laminate (30), in particular a photovoltaic module, the system comprising a film holder (200) adapted to apply a film (210) to the laminate (30) under pressure for laminating. The spacing device (100) comprises a circulating belt (110) and a plurality of spacing members (120) connected to the belt and configured to at least partially form a frame (150) for the laminate (30) in at least a portion of the circulating belt (110), thereby inhibiting edge compression of the laminate (30) during laminating.

Description

TECHNICAL FIELD

[0001] The present invention relates to a spacer device for a system for laminating laminates, in particular photovoltaic modules with a film, and to a method for manufacturing such a spacer device. BACKGROUND

[0002] The production of photovoltaic modules comprises laminating the layers (stack of layers) of a laminate under pressure and high temperature. For this lamination, so-called film laminators are widely used. The process of lamination can be largely automated by a system which inter alia transports a plurality of such laminates into a lamination chamber, in which a clamping film in a clamping frame is pressed from above onto the laminate to be laminated. At the same time, heat is supplied to the laminate and the pressure around the laminate is reduced by suction means, which can increase or influence the pressure of the film.

[0003] Under the pressure of the film, the surface of the film extends beyond the laminate, in the edge region of which an over-pressing can occur. This can lead to edge shrinkage, i.e. a reduction in thickness in the edge region of the laminate. This can generate tensions within the laminate, which can lead to delamination or the breakage of a cover glass, for example, immediately after production or after a longer period of time.

[0004] Figure 6 A schematic representation of such an edge pressing situation is shown. On the left side of the figure a cross section of a system for laminating a laminate 30 is shown. A film 210 is pressed onto the laminate 30 for lamination (for example by forming a suitable positive or negative air pressure). In a film laminator such a film 210 can have a thickness of for example up to 8 mm and an area of up to several square meters. In the edge region of the laminate 30, the surface of the film 210 overhangs the laminate 30, whereby the mechanical pressure exerted by the film 210 on the laminate 30 presses the laminate 30 there more than in the central region of the laminate 30. This leads to a compression of the edges of the laminate. On the right side of the figure an enlarged cross sectional view of the pressed edge region of the laminate 30 is shown. Here, the laminate 30 comprises two glass layers 33 arranged around a layer 37 comprising plastic and solar cells embedded therein. The glass layers can have a thickness of for example up to 2.5 mm, the plastic layer can have a thickness of for example in the order of a millimeter, for example the laminate 30 can have a thickness of 5 mm when not under pressure. Due to the over-pressing, the thickness of the laminate 30 decreases towards the edges of the laminate 30 (on the right side of the figure). This leads to a constant stress, which limits the lifetime and quality of the photovoltaic module.

[0005] There is a need to economically and efficiently suppress edge compression in a film laminator, which is also advantageously suitable for retrofitting already running film laminators, so that the existing automated processes can continue to be maintained. SUMMARY

[0006] The above problems are solved by the spacing device according to claim 1 and the method for manufacturing a spacing device according to claim 11. The dependent claims relate to further embodiments which are advantageous for the purpose of the independent claims.

[0007] The invention relates to a spacing device for a system for laminating a laminate, in particular a photovoltaic module. The system comprises a film holder which is adapted to apply a film to the laminate while applying pressure for the purpose of lamination. The spacing device comprises a circulating belt and a plurality of spacing members which are connected to the circulating belt and are adapted to at least partially frame the laminate in at least a portion of the circulating belt, thereby suppressing edge compression of the laminate during lamination.

[0008] In particular, the film can be held in a clamping frame which is lowered onto the laminate. The pressure can be applied indirectly onto the laminate, i.e. not by direct contact. In particular, a release tape can be located between the film and the laminate during lamination for protection and for better release of the film from the laminate after lamination (so-called "release sheet"). The surface of the film is suspended above the corresponding surface of the laminate, and the frame which is partially formed by the spacing members supports the film immediately adjacent to the laminate in a manner adapted to reduce the pressure which increases in the edge region of the laminate, in particular caused by the tension of the film.

[0009] The frame formed by the spacing members can be only partial; in particular, it need not completely enclose the laminate. It can be sufficient to support the film at certain suitable points to reduce the edge load. In addition or alternatively, recesses of the frame can be adjusted by the geometry of the system. The frame can also be formed only by a combination of spacing members distributed over several belts.

[0010] The spacing members are designed such that they can rotate with the belt. They can each be directly connected to the belt individually, for example by gluing, welding, stitching or screwing. In embodiments, however, the belt also has pull rods for its circulating movement, and the spacing members can comprise a frame which is at least partially formed, which is attached to one or more pull rods and circulates with the belt. To this end, the frame is advantageously designed to be flexible in the direction of rotation, but perpendicular to the belt is pressure-resistant and dimensionally stable. This can be achieved, for example, by introducing a suitable plastic material (e.g. rubber) or metal (e.g. chain belt) which forms all or part of the frame.

[0011] Hence, the spacing members can comprise a flexible material, such as silicone, or a Teflon material, or a terpolymer such as EPDM, or comprise a non-flexible material, such as aluminum or steel. In particular, the flexible material can be used to circulate around the spacing members and occur in spaced segments, for example in a continuous shape of a belt, cord and / or rope, or in combination with a non-flexible material. The non-flexible material can be used as, for example, a chain belt, a zipper, or as a rod, tooth or support element of the spacing members.

[0012] Optionally, performing the lamination comprises creating a negative pressure, and the spacing members are configured such that the resulting frame has openings to facilitate the escape of gas from the lamination panel or the area surrounding it during the performing of the lamination.

[0013] For example, there are film lamination systems in which the pressure of the film on the lamination panel is at least partially established by creating a negative pressure in the area surrounding the lamination panel. Alternatively or additionally, a vacuum is drawn around the lamination panel during the performing of the lamination to facilitate the escape of air from the lamination panel. In particular, this can also be used to prevent air or other gases from being trapped in the lamination panel.

[0014] Optionally, fusion of the plastic in the lamination panel occurs during the performing of the lamination, and the spacing members are formed such that the resulting frame has recesses or gaps formed to the lamination panel, such that the escaping plastic can be received or removed during the performing of the lamination.

[0015] For example, a lamination panel for a photovoltaic module can comprise a layer of plastic material, such as ethylene vinyl acetate (EVA) or polyolefin (PO), sandwiched between two glass panels, which encapsulates a plurality of photovoltaic cells and associated contacts. During the performing of the lamination, such plastic material can escape laterally from the lamination panel between the glass panels. The spacing members can be configured to allow and / or facilitate such escape of plastic material, for example by a suitable shape of the frame formed by the spacing members. For example, the frame can have recesses, widenings, grooves, channels and / or other recesses on the side facing the lamination panel to provide sufficient space for the escaping plastic material or encapsulation material.

[0016] Optionally, the film holder is configured to apply the film to the lamination panel with a vertical movement, and the spacing members are configured such that the resulting frame is flush with the lamination panel when the film is applied to the lamination panel.

[0017] This flush end face serves to prevent excessive deflection of the film, as is the case with conventional systems. This can be achieved, for example, by spacing members having the same height as the lamination panel to be produced and / or being as close as possible to perform the lamination at least on the side facing the film.

[0018] The height of the spacer members can also exceed the height of the laminate. This can be the case in particular if there is a distance between the laminate and the spacer members when the film is pressed onto the laminate; for example, the spacer members can exceed the laminate thickness of the laminate by a few percent. The height of the spacer members can depend on the distance between the laminate and the spacer members.

[0019] Optionally, the spacer members have at least one of the following materials: steel, plastic, silicone, hard rubber, a matrix material with a non-stick coating.

[0020] Optionally, the spacer members are interchangeably connected to the peripheral band to form a frame with dimensions and / or a height that are suitable for different laminates.

[0021] For example, only holders can be attached to the circulating band, in each case elements suitable for a particular laminate can be inserted into the holders to form the spacer members. If the spacer members are connected to the pull rod of the band, the connection to the pull rod can be detachable, so that different spacer members for a respective different laminate can be connected to the pull rod.

[0022] Optionally, the circulating band is a conveyor belt, which is suitable for placing a laminate thereon and transporting it at least partially through the laminating system, or a stripping band, which is suitable for intervening between the film and the laminate during the lamination and facilitating the peeling of the film from the laminate after the lamination.

[0023] In particular, the conveyor belt or the transport sheet can comprise a material such as Teflon, which is suitable for easily lifting the laminate from the conveyor belt after the lamination and for preventing the adhesion of material escaping from the laminate. Furthermore, the conveyor belt advantageously has sufficient pressure and heat resistance to be able to ensure its function as a peeling sheet for the laminate during the lamination. The stripping band or the peeling sheet can also be designed as a protective layer for the laminate.

[0024] Optionally, the spacing device comprises a peeling sheet as a circulating band, the spacer members are applied to the peeling sheet, and in addition, a further circulating band has further spacer members, the further circulating band being a conveyor belt, which is suitable for transporting the laminate for the lamination. Furthermore, the further spacer members of the conveyor belt can be configured to engage at least some of the spacer members during the lamination, thereby forming a stepless frame for the laminate, so that the edge compression of the laminate is inhibited during the lamination.

[0025] The term "stepless" means in particular a uniform height of the frame. For example, the spacer members can be attached to the transport sheet located below the laminate, but also to the peeling sheet located above the laminate. Similarly, a part of the build height of the frame can be applied to the transport sheet and the other part of the build height to the peeling sheet, so that the target height of the frame is achieved when the two build heights are superimposed during the lamination process.

[0026] Optionally, the plurality of spacing members comprises at least two spacing members which are configured to interlock in a zipper-like fashion when forming the at least partial frame during lamination.

[0027] The interlocking spacing members can be on the same strip or on different strips.

[0028] Optionally, at least one of the spacing members can further comprise a chamfer to prolong the service life or lifetime of the membrane. Without the bevel, the sharp edges of the spacing members can cut into the membrane, thereby damaging the membrane. Alternatively or in addition, the shape is also suitable to exert a force in the direction of the horizontal force on the lamination panel, thereby reducing the gap between the spacing member and the lamination panel in order to minimize air entrainment (at least assuming that the spacing member has a certain flexibility).

[0029] The invention also relates to a manufacturing method for a spacing device of a system for laminating a lamination panel, in particular a photovoltaic module. In this respect, the system comprises a membrane holder which is adapted to apply a membrane for lamination to the lamination panel by exerting a mechanical pressure. The method comprises the following steps:

[0030] providing a circulating strip; and

[0031] attaching a plurality of spacing members to the circulating strip such that the spacing members at least partially form a frame around the lamination panel during lamination, thereby suppressing compression of the edges of the lamination panel when applying the membrane to the lamination panel during lamination.

[0032] The spacing device is thus in particular used to prevent deflection of the lamination panel at the edges during lamination by the mechanical support provided by the spacing members. The spacing members directly and / or indirectly (e.g. in case of a release sheet extending between the membrane and the spacing device) support the membrane in the area of the membrane protruding beyond the lamination panel such that additional pressure exerted by the tension of the membrane in the edge area of the lamination panel is at least reduced.

[0033] The advantages of embodiments of the spacing device as described above in particular include the possibility of low-cost production which only requires an adaptation of the geometry of already existing systems for membrane lamination and can also be retrofitted in such systems. BRIEF DESCRIPTION OF DRAWINGS

[0034] Embodiments of the invention will be better understood from the following detailed description with reference to the drawings, although the detailed description and drawings are not to be construed as limiting the disclosure to particular embodiments, but are merely for explanation and understanding.

[0035] Figure 1 A spacing device for a system for laminating a lamination panel is shown.

[0036] Figure 2 Two cross sections of another embodiment of a spacing device of a system for laminating a laminate are shown.

[0037] Figure 3 Views of two embodiments of a spacing device of a conveyor for guiding on a pull rod are shown.

[0038] Figure 4 A cross section of a spacing device for attachment to a tow bar is shown.

[0039] Figure 5 A cross section of a system for laminating with a spacing device shows more details of the spacing members.

[0040] Figure 6 A schematic drawing showing how edge extrusion occurs in a conventional system for laminating without a spacing device is shown.

[0041] Figure 7 Manufacturing method steps of a spacing device of a system for laminating a laminate with a film are shown. DETAILED DESCRIPTION

[0042] Figure 1 An embodiment of a spacing device 100 of a system for laminating a laminate 30, in particular a photovoltaic module, is shown. The system comprises a film holder (holding device) 200 configured to apply a film 210 to the laminate 30 upon application of pressure for laminating. The spacing device 100 comprises a circulating belt 110 guided by pulleys and a plurality of spacing members 120 connected to the belt and configured to form a frame 150 for the laminate 30 in at least a portion of the circulating belt 110, thereby inhibiting edge compression of the laminate 30 by the film 210 during laminating.

[0043] To avoid edge compression of the film 210, the effective press region of the film 210 should not be larger than the laminate 30 to be manufactured. This is achieved here by the plurality of spacing members 120 forming a frame 150 for the laminate 30. Advantageously, the frame 150 is only slightly larger than the outer edges of the laminate and at least the height of the laminate 30 to be manufactured. Advantageously, the laminate 30 is placed in the lamination frame 150 before the process starts. By protecting the frame 150 from excessive edge compression by the film 210, the laminate 30 can be manufactured without edge compression. The distance of the spacing members 120 from the laminate 30 also depends on the placement accuracy of the laminate 30 on the belt 110. The placement accuracy varies between different systems for performing lamination. In examples, the spacing between the laminate 30 and the frame 150 can be approximately 3 to 7 mm. Thus, the embodiments allow for an automated process without manual handling and allow for the laminate 30 to be manufactured without edge or edge compression.

[0044] In the shown figures, the circulating belt 110 in particular transports the laminate 30 by at least a part of the system for performing lamination. Before the process starts, the laminate 30 is conveyed and placed on such a transport sheet. Embodiments are conceivable in which, in addition to the transport sheet, the belt 110 is formed with spacing members 120. In particular, there can be a plurality of belts 110, whose respective spacing members 120 together form a frame 150 for the laminate 30 during lamination. To this end, the spacing members 120 can also be interlocked in a zipper-like manner.

[0045] In the shown figures, the spacing members 120 are fixed to the belt 110. The spacing members 120 can also be larger frames 150, forming a structure that only needs to be connected to the belt 110 at specific locations. The spacing members 120 can be interchangeable, so that different spacing members 120 can be used to form a frame 150 for different laminates 30.

[0046] Figure 2Two cross sections of a part of the system for lamination are shown, one arranged above the other, the lamination system having a film holder 200 and a film 210 applied to a lamination plate 30 for lamination. The lamination plate 30 is located on a circumferential conveyor belt or transport web 113 above a heating plate 300. The release web 115 is also circumferential, extending between the film 210 and the lamination plate 30 to protect the lamination plate 30 from contamination, for example, to facilitate lifting the film 210 from the lamination plate 30 after lamination has been performed. In the system for lamination, the thickness of the release web 300 can be, for example, 0.3 millimeters. Spacing members 120 are shown adjacent to the lamination plate 30 to prevent the film 210 from pressing on the edges of the lamination plate 30. In the embodiment shown, the spacing members 120 are attached to the webs 113, 115 in the laminator. Here, it is possible to attach to the transport web 113 located below the lamination plate 30 and / or to the release web 115 located above the lamination plate 30. The frame 150 formed by the spacing members 120 can include openings positioned perpendicular to the lamination plate 30 to facilitate the evacuation of the area around the lamination plate 30. The bevel 122 on the edge of the spacing members 120 increases the service life of the film 210.

[0047] In the cross sections shown in the figures, the film 210 is lowered onto the lamination plate 30 or onto the release web 115. As a result, the film 210 encloses a lamination plate cavity around the lamination plate 30. In the lower cross section, the pressure is shown by the arrows above the film 210, which presses the film 210 against the release web 115 and the lamination plate 30. The pressure can be generated or assisted by, for example, overpressure of a fluid, for example air, above the film 210, but also by evacuation of air from the lamination plate cavity. During the lamination process, heat is applied to the lamination plate 30 by the heating plate 300 shown below the transport web 113 to perform the lamination.

[0048] Figure 3 Two views of each embodiment of the spacing device 100 are shown, one above the other. In each of the two parts of the figure, a top view of a portion of the circulating conveyor belt 113 is shown, which is pulled through the lamination system via a pull rod 117. In the example of a film lamination system, both the conveyor belt 113 and the release web 115 (not shown here) are attached to such a pull rod 117 and guided by it through one or more lamination plate cavities or sections of the system for lamination. The conveyor belt 113 can be continuous or can be interrupted; in particular, a further portion of the conveyor belt 113 can be adjacent to each right side of the pull rod 117, or the conveyor belt 113 can be interrupted there. On the conveyor belt 113, the direction of rotation points in each case in the direction of, for example, the right edge of the image, a plurality of lamination plates 30 are located in the frame 150 formed by the spacing members 120.

[0049] In the upper part of the figure, the spacer 120 is directly attached to the conveyor belt 113. The frame 150 may also have a spacer 120 that extends in the transport direction and is made of a stretchable or flexible but pressure-resistant material that allows the frame 150 to circulate.

[0050] In the lower part of the figure, the frame 150 for each laminate 30 is designed as a spacer 120, which is not directly attached to the conveyor belt, but is attached to and guided by the pull rod 117 like the conveyor belt 113.

[0051] Figure 4 It shows Figure 3 The lower part of the embodiment is shown in cross-section. A pull rod 117 and an upper pull rod 118 can be seen, pointing in the circulation direction to the right of the figure. A conveyor belt 113 is attached to the pull rod 117, and a stripping belt 115 is attached to the upper pull rod 118. The two pull rods 117 and 118 pull belts 113 and 115 through the system for lamination. Belts 113 and 115 can be continuous or intermittent; in particular, additional sections of each of the respective belts 113 and 115 can be adjacent to the right side of the pull rods 117 and 118, or each of the respective belts 113 and 115 can be interrupted there.

[0052] Spacer member 120 is also attached to pull rod 117 resting on conveyor belt 113. Spacer member 120 may be, for example, bolted, welded, or clamped to pull rod 117. Spacer member 120 has frame 150 for one or more laminates 30 (not shown here). Spacer member 120 may alternatively be attached to and pulled by pull rod 118.

[0053] Figure 5 Further details of the spacer member 120 for an embodiment of the spacer device 100 are shown. A cross-section is shown passing through the conveyor belt 113, the laminate 30 framed by the spacer member 120, and a portion of the film retainer 200. The spacer member 120 is thus connected to the conveyor belt 113. They have a shape that allows material to escape from the laminate 30 during lamination. In particular, for example, from the plastic layer 37 (reference 100). Figure 6EVA of the encapsulant material can escape from the lamination panel 30 during lamination. In the illustrated embodiment, the shape of the spacer member 120 is a bevel 125. The spacer member 120 reduces the leakage of encapsulant material, as the lamination panel edges are not excessively squeezed. Thus, the risk of adhesion has been reduced or minimized. By the bevel 125, the spacer member 120 is given a slope towards the lamination panel edges, so that the outflowing encapsulant material has as small a contact surface as possible with the spacer member 120. The escaped material reaches the conveyor belt 113 by this shape. In this regard, it is advantageous if the spacer member 120 has a non-stick material coating (e.g. Teflon) like the conveyor belt 113, which prevents the adhesion of the escaped material.

[0054] Furthermore, the outer spacer member 120 comprises a bevel 122 for protecting the film 210 (not shown here) pressed from above. Sharp edges can damage the film 210, which can have a thickness in the range of less than one centimeter; the bevel 122 allows the film 210 to rest on a larger area, thus increasing the service life of the film 210.

[0055] Figure 7 Steps of a method for manufacturing a spacing device 100 for a system for laminating lamination panels 30, in particular photovoltaic modules, are shown, the system comprising a film holder 200 adapted to apply a film 210 for laminating to a lamination panel 30 under application of pressure. A first step S100 comprises providing a circulating belt 110, which can be part of an existing system. A further step S200 comprises attaching a plurality of spacer members 120 to the circulating belt 110 in such a way that the spacer members 120 at least partially form a frame 150 around the lamination panel 30 during lamination, thereby inhibiting the compression of the edges of the lamination panel 30 during the application of the film 210 to the lamination panel 30.

[0056] The features of the application disclosed in the description, the claims and the drawings are essential to the application, alone or in any combination.

[0057] List of reference signs

[0058] 30 lamination panel

[0059] 100 spacing device

[0060] 110 circulating belt

[0061] 113 conveyor belt (transport sheet)

[0062] 115 release belt (release sheet)

[0063] 117, 118 tension rod

[0064] 120 spacer member

[0065] 122 bevel to increase film life

[0066] 125 recess to contain escaped (exiting) material

[0067] 150 frame

[0068] 200 film holder (retainer)

[0069] 210 film

[0070] 300 hot plate

Claims

1. A spacer device (100) for a system for laminating a laminate (30), the laminate (30) being a photovoltaic module, the system comprising a film holder (200) adapted to apply a film (210) to the laminate (30) under pressure for laminating, the spacer device (100) comprising: a circulating belt (110); a plurality of spacer members (120) connected to the circulating belt and configured to at least partially form a frame (150) for the laminate (30) in at least a portion of the circulating belt (110) and to inhibit edge compression of the laminate (30) during laminating; and at least one pull rod (117, 118) detachably mounted to a spacer member (120) and to which the at least partially formed frame (150) is attached.

2. The spacer device (100) according to claim 1, wherein the laminating comprises forming a negative pressure, and wherein the spacer members (120) are formed such that the formed frame (150) has an opening to facilitate gas escape from an area in or around the laminate (30) during laminating.

3. The spacer device (100) according to claim 1, wherein During laminating, fusion of plastic occurs in the laminate (30), and wherein the spacer members (120) are formed such that the formed frame (150) has a recess (125) or forms a gap with the laminate (30) to receive expelled plastic during laminating.

4. The spacer device (100) according to claim 1, wherein, the film holder (200) is formed to apply the film (210) to the laminate (30) with a vertical motion, and wherein the spacer members (120) are formed such that the formed frame (150) is flush with the laminate (30) when the film (210) is applied to the laminate (30).

5. The spacer device (100) according to claim 1, wherein the spacer members (120) comprise at least one of the following materials: steel, plastic, silicone, hard rubber, a matrix material with a non-stick coating.

6. The spacer device (100) according to claim 1, wherein the spacer members (120) are interchangeably connected to the circulating belt to form frames (150) with dimensions and / or heights adapted to different laminates.

7. The spacer device (100) according to claim 1, wherein the circulating belt (110) is any one of the following: a conveyor belt (113) adapted to place the laminate (30) on the conveyor belt (113) and to be at least partially transported through the laminating system; a release belt (115) configured to intervene between the film (210) and the laminate (30) during laminating and to facilitate peeling of the film (210) from the laminate (30) after laminating.

8. The spacer device (100) according to claim 1, wherein the circulating belt (110) is a release belt (115) configured to intervene between the film (210) and the laminate (30) during laminating and to facilitate peeling of the film (210) from the laminate (30) after laminating; and wherein said spacing device (100) further comprises: a further endless belt having further spacing members, said further endless belt being a conveyor belt (113) adapted to transport said laminated sheets (30) for lamination, and said further spacing members being formed to engage one or more of said spacing members (120) during lamination to form a stepless frame (150) for said laminated sheets (30) and thereby to inhibit edge compression of said laminated sheets (30) during lamination.

9. The spacer device (100) according to claim 1, wherein said plurality of spacing members (120) comprises at least two spacing members configured to interlock in a zipper-like manner when forming said at least partial frame (150) during lamination.

10. The spacer device (100) according to claim 1, wherein at least one of said spacing members (120) comprises a bevel (122) elongating the service life of said film (210) and / or adapted to establish pressure towards said laminated sheets (30) when said film (210) is applied to said laminated sheets (30) by mechanical pressure exerted on said spacing members via said film (210).

11. A method of manufacturing a spacing device (100) for a system for laminating laminated sheets (30), said laminated sheets (30) being photovoltaic modules, said system comprising a film holder (200) adapted to apply a film (210) for lamination under mechanical pressure to said laminated sheets (30), said method comprising the steps of: providing an endless belt (110) at step S100; attaching a plurality of spacing members (120) to said endless belt (110) at step S200, such that said spacing members (120) at least partially form a frame (150) around said laminated sheets (30) during lamination, thereby inhibiting edge compression of said laminated sheets (30) during application of said film (210) to said laminated sheets (30); and detachably mounting at least one tension rod (117, 118) to spacing members (120), wherein the at least partially formed frame (150) is attached to said at least one tension rod (117, 118).

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