Method for manufacturing a glazing unit
Patent Information
- Application Number
- EP2023720250
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-04-14
- Filing Date
- 2023-04-13
- Publication Date
- 2025-02-19
AI Technical Summary
The existing methods for manufacturing small, curved laminated glazing are energy-intensive, logistically challenging, and inefficient, particularly for thin glasses, as they require complex cold bending and large installations, making it difficult to produce thin, curved laminated glazing in an industrial and simple manner.
A process involving a laminated glazing structure with two thin glass sheets (each less than 1.6mm thick) separated by a thin interlayer film, where the assembly is encapsulated and shaped using a deformable encapsulation device that applies a seal around the glazing to give it a curved shape, allowing for simultaneous encapsulation and forming, and optionally reinforcing the glass sheets chemically or thermally.
This method enables the production of thin, curved laminated glazing with reduced thickness and mass, maintaining the benefits of laminated glass while achieving complex shapes, such as cylindrical or spherical forms, with a maximum deflection of 70mm and surface area up to 0.8m2, and significantly reducing energy consumption and logistical complexities.
Smart Images
Figure 1.1
Abstract
Description
Description Title of the invention: Method for manufacturing glazing
[0001] It is known to manufacture glass with a specific shape, particularly automotive side windows, using a toroidal bending process. These conventional side windows are monolithic panes of glass heated to 650°C and then rapidly cooled to temper them while giving them a toroidal shape. This tempered glass has the dual advantage of being more resistant to mechanical stress and shattering into numerous small pieces if broken.
[0002] The manufacture of laminated glazing based on these classic side panes consists of a sandwich of two formed and hardened panes of glass (in the sense that they are cooled rapidly) joined by a sheet of a PVB elastomer interlayer.
[0003] For the manufacture of small panes of glass, the same tools as for conventional panes are used, which inevitably leads to logistical problems (handling and storage of small panes) and industrial production problems (use of large, energy-intensive installations to produce small panes of glass).
[0004] Furthermore, for thin panes of glass, all shaping is done by cold bending, but always with a support glass: either with a thick tempered glass serving as a base for the lamination, or with piston glass to create a sandwich of thin panes. Shaping thin panes is very complex, and cold bending therefore seems to be the best option for achieving this, as the proposed solutions systematically involve a "master" glass to guarantee the correct geometry of the sandwich (in the case of small windows such as quarter windows, it would therefore be necessary to continue forming a small tempered glass to create an assembly with a thin pane on one of the two sides).
[0005] Therefore, there is a need to find an alternative solution. Summary of the invention
[0006] The present invention seeks to provide an alternative solution to the prior F at, namely a process for producing curved and thin laminated glazing in a simple and industrial manner.
[0007] To this end, the present invention relates to a curved glazing unit comprising a first sheet of glass less than 1.6 mm thick and more preferably less than 1.2 mm thick, a second sheet of glass less than 1.6 mm thick and more preferably less than 1.2 mm thick, an intermediate film less thick than the thinnest sheet of glass in the glazing unit and arranged between the first and second sheets of glass, the glazing unit further comprising a seal encapsulating all sides of said glazing unit.
[0008] The invention further relates to a laminated glazing of curved shape resulting from the assembly of a first flat sheet of glass of thickness less than 1.6mm and more preferably less than 1.2mm, an interlayer sheet and a second sheet of glass of thickness less than 1.6mm and more preferably less than 1.2mm, the second sheet of glass being also flat before its assembly with the first sheet of glass and the interlayer sheet, said glazing further comprising a gasket encapsulating all its sides and in which the gasket is placed during the assembly to give the glazing its shape.
[0009] As an example, the first sheet of glass and / or the second sheet of glass is chemically or thermally strengthened.
[0010] In one example, the joint is reinforced by a reinforcing element.
[0011] According to one example, the reinforcing element includes at least one metal wire embedded in the joint.
[0012] As an example, the interlayer film is a sheet made of a material such as PVB or PET.
[0013] According to one example, the interlayer film is a layer deposited on one of the two sheets of glass of said glazing.
[0014] According to one example, the layer forming the interlayer film is an OCA resin or a natural rosin.
[0015] According to one example, the glazing has a maximum deflection of 70mm.
[0016] According to an example, the glazing has a thickness not exceeding 4mm, more preferably 3mm and even more preferably 2mm.
[0017] According to one example, the glazing has a maximum surface area of 0.8m2.
[0018] The invention further relates to a method for manufacturing curved glazing comprising a first sheet of glass less than 1.6 mm thick and more preferably less than 1.2 mm thick, a thermoplastic interlayer sheet and a second sheet of glass less than 1.6 mm thick and more preferably less than 1.2 mm thick, said method comprising:
[0019] - Obtain the first sheet of glass in flat form, the second sheet of glass in flat form and the interleaving film;
[0020] - Assemble the first sheet of glass in a flat form, the second sheet of glass in a flat form and the interlayer film with the interlayer film between the two sheets of glass to form an assembly;
[0021] - Place the assembly in an encapsulation device capable of surrounding the sides of the assembly with a seal;
[0022] - Install the seal;
[0023] Characterized in that said encapsulation device is capable of deforming the glazing during the installation of the seal.
[0024] According to one example, the process further includes, before the assembly stage, a chemical or thermal strengthening stage of the first sheet of glass and / or the second sheet of glass. Description of the figures
[0025] Other features and advantages will become clear from the description given below, which is indicative and in no way exhaustive, with reference to the attached drawings, in which:
[0026] - [Fig.1] represents a curved laminated glass pane;
[0027] - [Fig.2] represents a curved laminated glazing according to the invention;
[0028] - Figures 3 to 9 schematically represent the different stages, in cross-section, of the manufacturing process of the glazing according to the invention; Detailed description
[0029] A glazing 1 according to the invention is a laminated glazing, visible in [Fig. 1], comprising an outer glass 2 or first sheet, an inner glass 3 or second sheet and an interlayer film 4. The interlayer film 4 is arranged between the outer glass and the inner glass.
[0030] Exterior glass 2 is glass with a thickness of less than 1.6mm and more preferably less than 1.2mm.
[0031] The inner glass 3 is a glass with a thickness of less than 1.6mm and more preferably less than 1.2mm.
[0032] Glazing 1 comprises two sheets of glass of the same thickness or of different thicknesses.
[0033] The interlayer film 4 has a thickness less than the thickness of the thinnest glass pane in the sandwich assembly, or in other words, its thickness is less than 50% of the total glazing thickness. Preferably, the interlayer film is thinner than the thinnest glass pane, which has the lowest thickness. The interlayer film 4 can be in the form of a sheet or a film and can be made of a thermoplastic material such as PVB or PET.
[0034] The glazing 1 has a thickness not exceeding 4mm, more preferably 3mm and even more preferably 2mm.
[0035] Glazing 1 is made by, firstly, equipping the outer glass and the inner glass.
[0036] In a second step, the inner pane 3 and the outer pane 2 are joined with the interlayer film 4, which is placed between the two panes 2 and 3 before undergoing the conventional assembly process as shown in Figures 3 and 4. This assembly process may include a calendering step followed by a heating step in an autoclave oven. Once the glazing unit 1 is formed, the process consists of... shape to form a curved pane of glass.
[0037] According to the invention, the shaping of the glazing 1 is carried out simultaneously with its encapsulation. The encapsulation consists of providing the glazing 1 with a peripheral seal 5, as seen in [Fig. 2], which runs around and extends on all sides of the glazing. This encapsulation is useful for glazing intended to be inserted into a window or door opening. This seal 5 is made of a vulcanized TPE-type material such as PP / EPDLM or SEBS.
[0038] For this purpose, the encapsulation step uses an encapsulation device comprising a mold 6 into which at least a portion of the glazing is inserted and into which the gasket material is injected, as shown in [Fig. 5]. This mold 6 includes, for example, at least two dies enclosing the glazing to form a space 61 into which the material is injected. The gasket 5 extends over the entire periphery of the glazing, and the mold 6 is arranged accordingly.
[0039] According to the invention, the encapsulation device further comprises a glazing deformation means 7 used to shape said glazing. This glazing deformation means 7 comprises at least one actuator 70, as seen in [Fig. 9], controlled by a computer to apply at least one force F to the glazing to deform it. This force may be the result of at least one suction and / or at least one physical contact such as a stretch or a push, as seen in Figures 6 and 7. Indeed, the encapsulation device may be equipped with at least two different actuators 70 to shape the glazing. In a non-limiting example, the encapsulation device 7 may include a finger-type actuator 70 that makes contact with the glazing to begin shaping it. Subsequently, at least one suction-type actuator 70, such as a suction cup, may take over from the finger-type actuator F.
[0040] Thus, during encapsulation, the encapsulation device is used to simultaneously deposit the seal 5 on the sides of the glazing while deforming it as seen in [Fig.8].
[0041] The advantage of this simultaneous encapsulation and forming process is that the invention uses encapsulation to secure the forming. Indeed, the forming essentially consists of cold forming. This cold forming of the glazing implies that the glazing tends to return to its original shape when the force applied to it diminishes or disappears.
[0042] The advantage of the invention is that the encapsulation seal 5, which is applied simultaneously with the forming of the glazing, will harden. This hardening of the seal 5 occurs while the forming process is still underway; that is, the force exerted on the glazing to give it the desired shape is continuously applied. When the seal 5 hardens and reaches a certain level of hardness, it allows the position of the glazing 1 to be fixed. opposing its return to its initial position.
[0043] The present invention thus makes it possible to produce a thin but laminated glazing unit, retaining all the advantages of laminated glass (intrusion resistance, acoustic insulation, UV protection, etc.) while drastically reducing its thickness and mass. Currently, the minimum thickness of laminated products is 3.96 mm for 8 kg / m²; the present invention easily allows this to be reduced to around 3 mm (7.5 kg / m²). 2 ) or even 2mm (5kg / m 2 ).
[0044] The glazing according to the invention has a shape that can be cylindrical, spherical, or a complex shape. The resulting glazing can have a maximum deflection of 70 mm. The glazing is also characterized by its surface area, which has a maximum value of 0.8 m². The surface area and the deflection value are related; that is, the larger the surface area, the greater the deflection. Thus, for example, a surface area of 0.8 m² could have a deflection of 50 mm, and a surface area of 0.1 m², a deflection of 35 mm.
[0045] In one variant, the outer pane (or first sheet) 2 and / or the inner pane (or second sheet) 3 undergoes a hardening or strengthening process prior to the glazing assembly. This strengthening can be chemical or thermal.
[0046] One option for this hardening process is chemical tempering. This involves completely immersing the glass in a bath of molten salts, subjected to a temperature of approximately 400°C. The bath of these very specific salts allows for a chemical exchange that will permanently compress the outer surface of the glass.
[0047] According to a second option, this hardening process is a thermal strengthening process. This involves heating the glass and then rapidly cooling it to generate a specific stress within the glass. Unlike thermal tempering of thick glass, where the stresses in the glass result from a significant temperature gradient, the thermal strengthening process generates stress via a limited temperature gradient within the glass due to its thinness.
[0048] In a second variant, the seal 5 is reinforced. This means that the seal includes a reinforcing element. This reinforcing element could be, for example, a metal wire placed in the space formed by the mold 6 and overmolded, embedded within the material forming the seal. Of course, the reinforcement could take the form of any element capable of performing the same function. This seal reinforcement, which partly serves to maintain the curvature of the glazing, allows the use of a less resistant seal material. Alternatively, this seal reinforcement allows greater stress to be applied to the glass while still ensuring that the seal can maintain this curvature.
[0049] In a third variant, the interlayer film 4 between the two glass panes is chosen to be thinner than a commonly used PVB interlayer. For this reason, The interlayer is a material such as OCA (Optical Clear Adhesive) resin or natural rosin; that is, the interlayer is in the form of a layer. In this variant, the glazing manufacturing process includes the following steps:
[0050] -Cutting of glass from a large substrate followed by optional chemical tempering
[0051] -Deposition of the interlayer layer onto one of the two glass panes. The layer has a thickness of less than 100 µm, ideally 30 µm. This layer is cured by UV drying.
[0052] -Joining of the two glass panes by calendering (with a 90°C temperature change)
[0053] -Forming during encapsulation.
[0054] In cases where glass undergoes chemical tempering, it is possible to consider whether the chemical tempering is carried out before or after cutting. Indeed, the glass used to form glazing comes from large sheets of glass, known as PLF, with dimensions such as 3m x 6m. These large sheets are then cut to the correct shape and dimensions. Thus, while it is possible to perform chemical tempering after cutting the inner and outer panes, it is also possible to perform the tempering before cutting.
[0055] Of course, the present invention is not limited to the illustrated example but is susceptible to various variants and modifications which will become apparent to those skilled in the art.
Claims
Demands
1. Glazing (1) of curved shape comprising a first sheet of glass (2) of thickness less than 1.6 mm and more preferably less than 1.2 mm, a second sheet of glass (3) of thickness less than 1.6 mm and more preferably less than 1.2 mm, an intermediate film (4) of thickness less than the thickness of the thinnest sheet of glass of the glazing and arranged between the first sheet of glass and the second sheet of glass, the glazing further comprising a gasket (5) encapsulating all sides of said glazing
2. Curved laminated glazing (1) resulting from the assembly of a first flat sheet of glass (2) of thickness less than 1.6mm and more preferably less than 1.2mm, an interlayer sheet (4) and a second sheet of glass (3) of thickness less than 1.6mm and more preferably less than 1.2mm, the second sheet of glass also being flat before its assembly with the first sheet of glass and the interlayer sheet, said glazing further comprising a gasket (5) encapsulating all its sides and in which the gasket is placed during the assembly to give the glazing its shape.
3. Glazing according to claims 1 or 2, wherein the first sheet of glass and / or the second sheet of glass is chemically or thermally strengthened.
4. Glazing according to claims 1 to 3, wherein the joint is reinforced by a reinforcing element.
5. Glazing according to the preceding claim, wherein the reinforcing element comprises at least one metal wire embedded in the joint.
6. Glazing according to any one of the preceding claims, wherein the interlayer film is a sheet made of a material of the PVB or PET type.
7. Glazing according to any one of claims 1 to 5, wherein the interlayer film is a layer deposited on one of the two sheets of glass of said glazing.
8. Glazing according to the preceding claim, wherein the layer forming the interlayer film is an OCA resin or a natural rosin.
9. Glazing according to any one of the preceding claims, wherein it has a maximum deflection of 70mm.
10. Glazing according to any one of the preceding claims, wherein the glazing has a thickness not exceeding 4 mm, more preferably 3mm and even more preferably 2mm.
11. Glazing according to any one of the preceding claims, wherein the glazing has a maximum surface area of 0.8m2.
12. A method for manufacturing curved glazing comprising a first sheet of glass less than 1.6 mm thick and more preferably less than 1.2 mm thick, a thermoplastic interlayer sheet, and a second sheet of glass less than 1.6 mm thick and more preferably less than 1.2 mm thick, said method comprising - Obtain the first sheet of glass in flat form, the second sheet of glass in flat form and the interleaving film; - Assemble the first sheet of glass in a flat form, the second sheet of glass in a flat form and the interlayer film with the interlayer film between the two sheets of glass to form an assembly; - Place the assembly in an encapsulation device capable of surrounding the sides of the assembly with a seal; - Install the seal; Characterized in that said encapsulation device is capable of deforming the glazing during the installation of the seal.
13. The method of the preceding claim, wherein it further comprises, prior to the assembly step, a step of chemical or thermal strengthening of the first glass sheet and / or the second glass sheet.