System for breaking an internal shape in a sheet of glass, shaping installation and associated processes

Abstract

System for breaking an internal shape in a glass sheet, shaping installation and associated methods. The invention relates to a system for breaking (150, 250, 350) an internal shape (10_INT) in a glass sheet (10), and comprising: - contact means (151, 251, 351) configured to come into contact with the internal shape during a bending phase of the glass sheet, so as to apply a contact force at the level of the internal shape, - resistance means (131, 352) configured to apply, at the level of at least one peripheral shape (10_EXT) complementary to the internal shape and when said contact force is applied, a resistance force opposite to said contact force. Figure for the abstract: Fig. 2

Description

Title of the invention: System for breaking an internal shape in a sheet of glass, shaping installation and associated methods. Prior art

[0001] The present invention belongs to the general field of glass cutting and shaping.

[0002] The invention relates more particularly to a system for breaking an internal shape in a sheet of glass. The invention also relates to a shaping installation incorporating such a breaking system as well as corresponding breaking and shaping processes. The invention finds a particularly advantageous, though by no means limiting, application in the cutting and shaping of sheets of glass for manufacturing laminated or tempered glazing, in particular automotive glazing, such as fixed panoramic "canopy" type roofs, windshields, side windows, or rear windows.

[0003] In order to produce glazing having a specific shape, for example automotive glazing, it is known to first proceed by breaking an internal shape in a sheet of glass.

[0004] At this initial stage, two configurations are possible. The first configuration is that in which the sheet of glass corresponds to a "primitive," that is, a piece of glass in its flat state with a (approximately) rectangular shape resulting from a cut made at the outlet of a glass furnace, such as typically a float glass production furnace. In other words, in this first configuration, the internal shape is broken in its flat state and exhibits the dimensional characteristics of the glazing to be manufactured.

[0005] A second configuration is that in which the glass sheet is a piece of glass in a flat state already exhibiting the dimensional characteristics of the glazing to be manufactured. The breaking of the internal shape therefore aims here to create an opening in the glazing intended for the implementation of a functionality (example: passage of the cables of an antenna fixed on a glass roof, passage of the rear wiper shaft for a rear window, possible passage of roof bar fixing shafts in a glass roof, and more generally for the integration of electronic or mechanical elements, such as for example an optical system of the camera or lidar type).

[0006] Regardless of the first or second configuration envisaged, the breaking of the internal shape is generally carried out in several successive operations, including in particular: - the tracing of at least one cutting line (also called a "cutting line") corresponding to a superficial crack on the surface of the glass, and delimiting the internal shape in the sheet of glass, - a separation of the internal shape of the glass sheet.

[0007] Once the internal shape is broken, it can be shaped in a shaping installation. Figure 1 schematically represents, in its environment, an example of an embodiment of an INS_OLD shaping installation as known from the prior art.

[0008] As illustrated by [Fig.1], the INS_OLD installation includes a conveying device 12 corresponding more particularly here to a series of straight rollers aligned in a plane to achieve a horizontal displacement of the internal shape 1 which has been previously broken.

[0009] The conveying process initially takes place through a heating zone 11 conventionally comprising an oven, preferably of the tunnel type, so as to bring the inner form 1 to a softening temperature. The inner form 1 is then conveyed, directly from the oven, to a system 13 configured to shape the heated inner form 1.

[0010] Conventionally, the forming system 13 (also called the "bending system") corresponds to a bending station in which a lower frame 13_1 (also called the "pressing frame") lifts the inner form 1 and presses it against a surface 13_3 (also called the "bending surface") of an upper mold 13_2 (also called the "bending mold"), thus giving it the desired shape. These operations take place during an operating phase of the forming installation INS_OLD, called the "bending phase".

[0011] In more detail, when the inner shape 1 is appropriately positioned in the area occupied by the crowning system 13 (i.e., the inner shape 1 is waiting on the rollers, below the mold 13_2), the kinematics of the crowning system 13 are in particular as follows: - The pressing frame 13_1 is mounted towards the mold 13_2, in order to press the internal shape 1 against the doming surface, - the pressing frame 13_2 is lowered, the inner shape 1 being held against the mold 13_2 by means of suitable suction means 13_4 cooperating with air circulation means 13_5, such as typically through channels, at the level of the doming surface (example: vacuum pump).

[0012] Once the inner shape 1 has acquired its shape, it is taken over by a transfer system capable of transferring the inner shape 1 from the crowning system 13 to a cooling system 14 (example: quenching station).

[0013] The manufacture of glazing therefore requires the implementation of a significant number of operations (i.e., cutting an internal shape from a sheet of glass, shaping this internal shape, then transferring and cooling it, and finally completing the assembly of the glazing from the internal shape). This results in a particularly complex manufacturing process, this complexity having repercussions in terms of production rate but also in terms of cost.

[0014] Furthermore, the stresses applied to the cutting line to break the internal shape (e.g., shear stresses) can generate flaking at the edge of the glass. Although this phenomenon can be mitigated by shaping the edge of the internal shape before forming, this further complicates the manufacturing process. Alternatively, shaping can be carried out at the exit of the forming unit. However, the treatments the glass undergoes within the forming unit tend to accentuate flaking defects, thus limiting the effectiveness of the shaping. Description of the invention

[0015] The present invention aims to remedy all or part of the disadvantages of the prior art, in particular those set out above, by proposing a solution which makes it possible to break an internal shape in a sheet of glass (and therefore a fortiori to shape said internal shape and to manufacture glazing from it) in a more efficient, less complex and less costly way than the solutions of the prior art.

[0016] To this end, and according to a first aspect, the invention relates to a system for breaking an internal shape in a sheet of glass, said sheet of glass having at least one principal cutting line separating the internal shape from at least one peripheral shape complementary to said internal shape, said breaking system comprising: - contact means configured to come into contact with the inner shape during a bending phase of the glass sheet, so as to apply a contact force to the inner shape, - resistance means configured to apply, at the level of said at least one peripheral form and when said contact force is applied, a resistance force opposite to said contact force.

[0017] It should be noted that, within the framework of the present invention, the notion of "cutting line" encompasses two types of embodiment.

[0018] Thus, a first embodiment classically refers to a crack made on the surface of the glass sheet (i.e. superficial crack), such as for example with the help of a glassmaker's wheel.

[0019] A second embodiment refers to the generation, within the mass of the glass sheet, of substantially straight "weaknesses" (channels, energy filaments) which, ideally, extend between the two main faces of said sheet. These weaknesses form, in the cross-section of the sheet, a "weakening curtain" whose projection onto the main faces of the sheet determines the fracture contour. This second embodiment is, for example, carried out using a laser, as described in more detail later.

[0020] Thus, the breaking system according to the invention makes it possible to break the internal shape during an operating phase of the shaping installation, more particularly during the crowning phase.

[0021] In other words, and contrary to the prior art, no breaking operation is carried out prior to the introduction of the glass sheet into the shaping installation.

[0022] In this way, the breaking system takes advantageous advantage of the elements present in a forming installation to perform the breaking function, which not only helps to reduce the complexity and cost of manufacturing a glazing, but also to increase production rates.

[0023] The inventors further observed that breaking the internal shape during the bending phase, rather than prior to the introduction of the glass into the shaping installation, advantageously reduces edge stresses at the broken internal shape, while maintaining them at a level sufficient to guarantee the strength and solidity of the glazing to be manufactured. This aspect is important to prevent any subsequent breakage during the assembly and integration of the glazing.

[0024] In particular, edge compression stresses below 70 MPa, more specifically between 40 MPa and 60 MPa, were able to be measured.

[0025] Moreover, because the edge at which the breaking of the internal shape takes place presents appropriate compressive stresses, the use of shaping this edge is very strongly limited, or even eliminated.

[0026] In particular embodiments, the breaking system may further comprise one or more of the following characteristics, taken individually or in all technically possible combinations.

[0027] In particular embodiments, said at least one main cutting line is made by laser, in particular by Bessel beam pulsed laser or by laser filamentation.

[0028] The use of laser filamentation allows, once the internal shape has been broken, the production of a filamentated edge. A similar appearance is obtained when a Bessel beam pulsed laser is used. This result is particularly advantageous insofar as it gives said edge excellent mechanical stability useful for efficiently carrying out (i.e. without degradation) subsequent operations to the manufacture of the glazing, such as glazing encapsulation operations or integration of mechanical and / or electronic components.

[0029] More specifically, and as has been measured, the edge obtained in accordance with such arrangements exhibits average roughness values ​​between 0.01 µm and 10 µm, particularly between 0.1 µm and 2 µm. An additional advantage resulting from this excellent mechanical stability is the complete elimination of the need for edge shaping.

[0030] In particular embodiments, said at least one main cutting line is made by means of a first pre-cutting phase by pulsed laser using Bessel beams or by laser filamentation, so as to generate discontinuous embrittlement in the mass of the glass, and a second propagation phase of said discontinuous embrittlement, for example implemented by CO2 laser.

[0031] Carrying out such a second phase makes it even easier to break the internal shape during the doming phase.

[0032] In particular modes relating to a first embodiment, said bending phase is implemented by means of a bending system comprising a pressing frame and a bending mold including a bending surface, the resistance means comprising the pressing frame dimensioned so as to lift the glass sheet towards the bending mold at the level of said at least one peripheral form, and the contact means comprising at least one element making an extra thickness arranged fixedly on the bending surface to come into contact with the inner form when the glass sheet is lifted towards the bending mold.

[0033] In particular modes relating to a second embodiment, said bending phase is implemented by means of a bending system comprising a pressing frame and a bending mold including a bending surface, the contact means comprising a suction device, for example by suction effect, configured to suction the inner shape when the glass sheet is held against the bending surface, said suction being carried out in a direction opposite to the direction in which the glass sheet is lifted by the pressing frame towards the bending mold.

[0034] According to a more specific embodiment of this second variant, the resistance means comprise: - the pressing frame dimensioned so as to lift the glass sheet towards the bending mold at the level of said at least one peripheral shape, or - means of holding said at least one peripheral shape against the bending surface, said holding means being separate from the pressing frame, such as for example pressing elements arranged around the periphery of the bending mold and configured to press said at least one peripheral shape against the bending surface when the glass sheet is in contact with said bending surface.

[0035] In particular embodiments, the crowning system further comprises means for air circulation at the level of the crowning surface as well as means for air suction through said means for air circulation, the resistance means comprising said means for air suction as well as said means for air circulation.

[0036] In particular embodiments, the thickness of the glass sheet is between 1mm and 5mm, preferably between 1.4mm and 2.6mm, for example equal to 2.1mm.

[0037] In particular embodiments, said internal form is intended for the manufacture of glazing, such as for example automotive glazing of the windshield, canopy, side window or rear window type.

[0038] Advantageously, the glass sheet also carries at least one auxiliary cutting line connecting at least one main cutting line to the edge of the glass sheet.

[0039] In particular embodiments, the glass sheet is, before the bending phase, shaped to the dimensions of a glazing intended to be manufactured from said glass sheet, such as, for example, automotive glazing of the windshield, canopy, side window or rear window type, and in which breaking the internal shape defines an opening in the glass sheet, said opening being intended for the implementation of a functionality, such as, for example, the implementation of an optical system of the camera or lidar type.

[0040] It should be noted that, in addition to the advantages already mentioned above, these arrangements make it possible to obtain a homogeneous distribution of compressive stresses around the opening resulting from the breaking of the internal shape.

[0041] Furthermore, breaking the internal shape during the curving phase advantageously prevents the appearance of optical distortions in the vicinity of the opening. Such distortions, which are present in the prior art due to the opening being created before the glass sheet is introduced into the forming installation, induce poor optical quality in reflection of the glazing, also known as the "volcano effect" (the edge of the opening tends to counter-bulge, that is, to protrude from the curved surface on the side of the convex face of the glazing; seen from outside a vehicle, the edge of the opening therefore takes on a slightly volcano-like shape; this displacement of a few tenths of a millimeter is very visible in reflection).

[0042] According to a second aspect, the invention relates to an installation for shaping a sheet of glass bearing at least one main cutting line separating an inner shape from at least one peripheral shape complementary to said inner shape, said installation comprising a breaking system according to the invention.

[0043] According to a third aspect, the invention relates to a method for breaking an internal shape in a sheet of glass, said sheet of glass having at least one main cutting line separating the internal shape from at least one peripheral shape complementary to said internal shape, said method being implemented by a breaking system according to the invention.

[0044] According to a fourth aspect, the invention relates to a method for shaping a sheet of glass bearing at least one main cutting line separating an inner shape from at least one peripheral shape complementary to said inner shape, said method being implemented by a shaping installation according to the invention.

[0045] According to a fifth aspect, the invention relates to a method for manufacturing glazing, for example laminated glazing or tempered glazing, said manufacturing method comprising the steps of: - shaping a sheet of glass bearing at least one principal cutting line separating an internal shape from at least one peripheral shape complementary to said internal shape, said shaping being carried out in accordance with a shaping process according to the invention, - if said internal shape is intended for the manufacture of glazing, use of the broken internal shape to manufacture said glazing, - if the glass sheet is, before the bending phase, shaped to the dimensions of a glazing intended to be manufactured from said glass sheet and the breaking of the internal shape defines an opening in the glass sheet, said opening being intended for the implementation of a functionality, use of the peripheral shape to manufacture said glazing.

[0046] In particular embodiments, the manufacturing process further comprises, before the shaping step, a step of producing at least said main cutting line, in particular by Bessel beam pulsed laser or by laser filamentation.

[0047] According to a sixth aspect, the invention relates to glazing, in particular for motor vehicles, obtained by the manufacturing process according to the invention. Brief description of the drawings

[0048] Other features and advantages of the present invention will become apparent from the description below, with reference to the accompanying drawings, which illustrate an example of an embodiment without being limiting in any way. In the figures:

[0049] [Fig-1] the [Fig.1] already described above, schematically represents, in its environment, an example of the realization of a shaping installation as known from the prior art;

[0050] [Fig.2] [Fig.2] schematically represents, in its environment, a particular embodiment of a shaping installation comprising a breaking system according to the invention;

[0051] [Fig.3] [Fig.3] schematically represents an example of making a cutting line in a sheet of glass according to a laser filamentation technique;

[0052] [Fig.4] [Fig.4] schematically represents, from several views, an example of making a cutting line in a sheet of glass according to a Bessel beam pulsed laser technique;

[0053] [Fig.5] [Fig.5] represents an example of the realization of a sheet of glass, seen from above, bearing a main cutting line delimiting an internal shape intended to be broken during a bending phase of the shaping installation of [Fig.2];

[0054] [Fig.6] [Fig.6] schematically represents another example of the realization of a breaking system belonging to the shaping installation of [Fig.2];

[0055] [Fig.7] [Fig.7] schematically represents yet another example of the realization of a breaking system belonging to the shaping installation of [Fig.2];

[0056] [Fig.8] [Fig.8] schematically represents an example of the realization of a sheet of glass in the flat state, shaped to the dimensions of a windshield, and comprising an internal shape intended to be broken to integrate into the resulting opening a lidar type optical system;

[0057] [Fig.9] [Fig.9] represents, in the form of a flowchart, a particular method of implementing a shaping process according to the invention, as carried out by the shaping installation of [Fig.2];

[0058] [Fig. 10] [Fig. 10] represents, in the form of a flowchart, the main steps of a manufacturing process for glazing according to the invention. Description of the implementation methods

[0059] Fig. 2 schematically represents, in its environment, a particular embodiment of an INS_1 shaping installation according to the invention.

[0060] Said installation INS_1 is configured to perform the shaping of a sheet of glass 10. More particularly, the sheet of glass 10 is introduced whole into the INS_1 shaping installation, the final product obtained at the output of the INS_1 shaping installation being a piece of shaped glass corresponding to a portion of the glass sheet 10.

[0061] It follows in particular from these provisions that no breaking operation is carried out prior to the introduction of the glass sheet 10 into the forming installation. On the contrary, the breaking of an internal shape 10_INT in the glass sheet 10 is carried out during an operating phase of the forming installation INS_1, namely more specifically here during the bending phase.

[0062] For the remainder of the description, a sheet of glass is considered, without limitation, to be a primitive. Said sheet of glass 10 corresponds to a plate formed from a transparent material, such as mineral glass, such as soda-lime glass, aluminosilicate, or borosilicate.

[0063] For the purposes of this description, it is also assumed that the internal form 10_INT, after being broken and shaped, is intended for the manufacture of laminated glass for use in a motor vehicle, such as a car. It is important to note, however, that the invention also covers other embodiments in which the glass sheet 10 does not correspond to a primitive; these aspects will be described in more detail later.

[0064] More specifically, in the present embodiment, said glazing corresponds to an automobile windshield. In other words, the dimensional characteristics of the internal shape 10_INT are those of the windshield intended to be manufactured.

[0065] However, considering such a type of glazing is only one variant implementation of the invention. Generally speaking, there are no limitations on the type of glazing that can be manufactured using the internal form 10_INT. Thus, it could, for example, be glazing intended for the vehicle roof, such as a canopy, side windows, or even a rear window. It could also be tempered (monolithic) glazing.

[0066] More generally, there is no limitation attached to the use that can be made of the glazing thus obtained from the interior shape 10_INT (example: dwelling).

[0067] Furthermore, the invention is described here in the context of shaping a single sheet of glass 10. These considerations are not, however, limiting to the invention, it being understood that the operations described below can be iterated to shape a plurality of sheets of glass, such as for example a second sheet of glass used to manufacture laminated glazing.

[0068] In the present embodiment, the glass sheet 10 has a thickness between 1mm and 5mm, preferably between 1.4 mm and 2.6 mm, for example equal to 2.1 mm.

[0069] Of course, such glass thickness values ​​are given here for illustrative purposes only, and nothing precludes considering other values. Generally speaking, those skilled in the art are aware of the limitations that can be imposed on a sheet of glass in terms of thickness depending on its intended application, as well as the shaping technique used.

[0070] As mentioned above, the inner shape 10_INT represents a fraction of the glass sheet 10. For this purpose, the glass sheet 10 has a main cutting line TD_P separating the inner shape 10_INT from a peripheral shape 10_EXT complementary to said inner shape 10_INT.

[0071] The main cutting line TD_P can be made according to any known method, for example by surface tracing using a glass cutter wheel or by means of any other suitable cutting instrument, such as for example a laser.

[0072] It is important to note that this main cutting line TD_P does not in itself constitute a break in the inner shape 10_INT, but only a weakening (on the surface or within the mass of the glass) of its contour. Put another way, the main cutting line TD_P does not effectively separate the inner shape 10_INT from the peripheral shape 10_EXT.

[0073] In a more specific example, the main cut line TD_P is produced by Bessel beam pulsed laser or by laser filamentation. It is known that the use of such laser cutting techniques makes it possible to generate, within the mass of the glass sheet 10, substantially straight "weaknesses" which, ideally, extend between the two main faces of said sheet.

[0074] More specifically, and as schematically illustrated in [Fig. 3], laser filamentation relies on the formation of a plasma inside the glass sheet 10. To achieve this, an ultra-short pulse laser beam LAS_F, typically on the order of femtoseconds, is used. Focusing this laser onto the surface of the glass, using suitable optics (not shown in [Fig. 3]), generates an ionization phenomenon which in turn leads to an energy concentration within the glass. This energy concentration occurs in a targeted manner in the form of an "energy filament F_LAS_F" inside the glass. The relative motion of the laser beam LAS_F with respect to the glass sheet 10 creates, in the cross-section of the sheet 10, a "weakening curtain R_LAS_F" whose projection onto the principal faces of the sheet determines the main cutting line TD_P.The very high cutting precision of laser filamentation makes it a particularly suitable method for thin glass.

[0075] The Bessel beam pulsed laser, for its part, generates said Bessel beams using adapted optics (different from those used in laser filamentation). Typically, a Bessel beam has a diameter between 2 pm and 3 pm, and a length in air of approximately 10 mm. Furthermore, a Bessel beam is characterized by its ability to propagate without diffraction or dispersion over a certain distance. This means it can maintain a narrow diameter over a relatively long distance, making it a particularly suitable cutting method for thick glass. The "weaknesses" generated in the glass mass by Bessel beams take the form of channels, as schematically illustrated, for example, in [Fig. 4], which includes: - a first view 4A representing, in cross-section of the glass sheet 10, channels C_LAS_B spaced every 5 pm, - a second view 4B representing, in top view, the said C_LAS_B channels. The meeting of these discontinuous C_LAS_B channels also forms a "weakening curtain" whose projection onto the main faces of the sheet determines the main cutting line TD_P.

[0076] It follows from the above that the embrittlement curtain thus formed by laser filamentation or Bessel beam pulsed laser is created within the mass of the glass. It corresponds to discontinuous embrittlement useful for the subsequent breaking of the internal shape 10_INT.

[0077] More specifically, the generation of such discontinuous embrittlement can correspond, in the execution of the main cut line TD_P, to a first pre-cutting phase followed by a second phase of propagation of said discontinuous embrittlement throughout the glass. This second phase can be implemented using any method known to those skilled in the art, such as, for example, by CO2 laser, mechanical pressure, localized hot air blowing, etc. Carrying out such a second phase further facilitates the subsequent breaking of the internal form 10_INT.

[0078] An example of an embodiment of the glass sheet 10, viewed from above, is illustrated by [Fig. 5] by way of no limitation. As illustrated by [Fig. 5], the main cutting line TD_P is a closed contour strictly contained within the glass sheet 10.

[0079] It is important to note that the invention is not limited by the fact that the main cutting line TD_P corresponds to such a closed contour. Indeed, nothing precludes the possibility that the edge of the inner shape 10_INT comprises at least a portion defined by an open contour whose two ends are located at the level of the edge of the glass sheet 10 (which implies a fortiori that at least a portion of the edge of the inner shape 10_INT coincides with the edge of the glass sheet 10).

[0080] In addition to the main cutting line TD_P, and as illustrated by [Fig.5] without limitation, the glass sheet 10 also carries, in the present embodiment, a plurality of auxiliary cutting lines TD_A connecting the main cutting line TD_P to the edge of the glass sheet 10.

[0081] The presence of such auxiliary cutting lines TD_A is advantageous in that it creates additional weakening of the peripheral shape 10_EXT, which facilitates the breaking of the inner shape 10_INT.

[0082] There is no limitation on the number of auxiliary cutting lines TD_A that may be used. In particular, nothing precludes the complete absence of auxiliary cutting lines TD_A. Moreover, the auxiliary cutting lines TD_A may be produced using any known method (glass cutter, laser, etc.).

[0083] In the embodiment illustrated by [Fig.2], the forming installation INS_1 includes a heating zone 110, a conveying device 120, a crowning system 130, a transfer system (not shown in [Fig.2]) and a cooling system 140.

[0084] The heating zone 110 can be conventionally implemented using a furnace, preferably of the tunnel type, through which the glass sheet 10 is transported by the conveying device 120. The conveying device 120 corresponds more specifically here to a series of straight rollers aligned in a plane to achieve a horizontal movement of the glass sheet 10. The glass sheet 10 is thus transported along a horizontal straight path contained within this plane. However, considering such rollers is only one variant of the invention, and nothing precludes considering other variants, such as, for example, a conveyor belt.

[0085] Inside the heating zone 110, the glass sheet 10 is brought to a softening temperature which is preferably between 600°C (degrees Celsius) and 700°C.

[0086] The bending system 130 is arranged in the immediate vicinity of the outlet of the heating zone 110. More particularly, the bending system 130 is configured according to a bending station.

[0087] To this end, and in the present embodiment, the bending system 130 comprises a pressing frame 131 capable of lifting the glass sheet 10 and pressing it against a bending mold 132, thus giving the internal shape 10_INT the desired form. More particularly, the bending mold 132 comprises a bending surface 133 having said desired shape, against which the softened glass sheet 10 is pressed and then held by means of air suction means 134 (example: vacuum pump) capable of generating suction through air circulation means 135 at the level of the bending surface 133 (example: channels passing through the bending surface 133).

[0088] In the embodiment described here, and as mentioned above, the breaking of the internal shape 10_INT takes place during the bending phase implemented by the bending system 130. Consequently, the glass product that is supplied at the outlet of the The 130 bending system corresponds to the internal curved shape 10_INT (and not to the entire curved glass sheet 10). Details related to the implementation of the breaking of the internal shape 10_INT are described below.

[0089] According to a more particular embodiment, the pressing frame 131 and / or the bending mold 132 comprise heating means (not shown in the figures). Such heating means are advantageously configured to regulate the temperature of the glass sheet 10 (and more particularly the edge of the glass sheet 10) after it exits the heating zone 110, so that the shaping can be carried out at a predetermined temperature.

[0090] It should be noted that the crowning mold 132 can either be configured to be mobile in vertical translation (i.e., up / down movements of the crowning mold 132 relative to the conveying device 120) or remain fixed. These arrangements have an impact on the kinematics of said crowning mold 132 and / or the transfer system once the crowning has been completed. In particular, once the crowning has been completed, the gap between the crowning mold 132 and the conveying device 120 must be sufficient to allow a collection frame belonging to the transfer system to be positioned appropriately (i.e., below the crowning mold 132) in order to collect the formed inner shape 10_INT (collection being effected by dropping the inner shape 10_INT onto the collection frame).

[0091] During the transfer, the inner form 10_INT may undergo initial local cooling for a predetermined period, typically a few seconds, for example, by means of blow nozzles. This allows, in particular, for the glass to be subjected to appropriate mechanical stresses. In addition, the collection frame may optionally include heating means configured to precisely control the temperature of the inner form 10_INT (and more specifically the edge of the inner form 10_INT) during its transfer. These aspects being well known to those skilled in the art, they are not described in further detail here.

[0092] Within the cooling system 140, the inner shape 10_INT is rigidified, fixed, by the effect of forced cooling applied to it. This cooling makes it possible to reduce the temperature of the inner shape 10_INT sufficiently so that, when it leaves the cooling system 140, it retains a shape as close as possible to the shape obtained by the curvature system 130.

[0093] Generally speaking, any cooling method known to a person skilled in the art can be implemented, the choice of a particular method (quenching, semi-quenching, blow hardening, etc.) being only a variant of implementation of the invention.

[0094] The shaping installation INS_1 differs from the prior art in that it also includes a breaking system 150 configured to break said internal shape 10_INT outside the heating zone 110, and more particularly during the bending phase implemented by the bending system 130.

[0095] To this end, said breaking system 150 comprises: - contact means configured to (locally) make contact with the inner shape 10_INT during the bending phase of the glass sheet 10, so as to apply a contact force at the level of the inner shape 10_INT, - resistance means configured to apply, at the level of the peripheral shape 10_EXT and when said contact force is applied, a resistance force opposite to said contact force.

[0096] In the embodiment illustrated by [Fig.2], the contact means comprise an element 151 having an extra thickness arranged fixedly on the curvature surface 133 to come into contact (locally) with the inner shape 10_INT when the glass sheet 10 is lifted towards the curvature mold 132 by the pressing frame 131 to be shaped.

[0097] Furthermore, in the embodiment illustrated in [Fig. 2], the resistance means include the pressing frame 131. More specifically, in this embodiment, the pressing frame 131 is dimensioned to lift the glass sheet 10 towards the curving mold 132 at the level of said peripheral form 10_EXT. Put another way, the support of the pressing frame 131 against the glass sheet 10 is made at the level of the peripheral form 10_EXT.

[0098] It follows that the contact force applied by the thickened element 151 is directed from top to bottom, i.e. from the curved surface 133 towards the pressing frame 131. Conversely, the resistance force applied by the pressing frame 131 is directed from bottom to top, i.e. from the pressing frame 131 towards the curved surface 133. The rupture of the internal shape 10_INT results from the application of these two forces, and is therefore ejected downwards to be collected by the collection frame and transferred to the cooling system 140.

[0099] No limitations are attached to the material from which the thickened element 151 is made. In particular, said material is chosen so as to be able to withstand the temperatures encountered during the implementation of the curvature (typically on the order of 600 °C). For example, said material may be stainless steel.

[0100] Moreover, it is understood that the thickness of element 151 is adapted to allow the internal shape 10_INT to be broken without preventing its prior shaping. This thickness is, for example, between 1 mm and 1 cm.

[0101] It should be noted that, in the example of [Fig. 2], the contact means comprise a single thickened element 151, and that this element is substantially centered with respect to the inner shape 10_INT. However, nothing precludes the possibility of having several thickened elements distributed over the convex surface 133 so as to make contact with the inner shape 10_INT at different locations.

[0102] It can also be noted that using the pressing frame 131 thus dimensioned is particularly advantageous because it allows, on the one hand, the use of an already existing element of the shaping installation INS_1, and, on the other hand, avoidance of marking the glass at the level of the internal shape 10_INT.

[0103] In a more specific embodiment, the thicker element 151 can be configured so as to be retractable inside the bending mold 132. These arrangements are advantageous in the context of sheet-by-sheet bending, i.e. successive bending of the inner and outer sheets respectively intended to form laminated glazing and where it is important to avoid marking one of said inner or outer sheets.

[0104] It has been considered so far that the contact means and the resistance means correspond respectively to the element 151 making an extra thickness and to the pressing frame 131. These provisions are however not limiting of the invention, and nothing excludes considering other embodiments in which these different means differ in whole or in part.

[0105] Fig. 6 schematically represents another example of an embodiment of a breaking system 250 in which the contact means comprise a suction device 251, for example by suction effect (example: arm equipped with a suction end), configured to suction the inner shape 10_INT when the glass sheet 10 is held against the bending surface 133. Thus, said suction is carried out by the suction device 251 in a direction opposite to the direction in which the glass sheet 10 is lifted by the pressing frame 131 towards the bending mold 132.

[0106] In the example of [Fig.6], and similarly to what has been described above with reference to [Fig.2], the resistance means comprise the pressing frame 131 dimensioned so as to lift the glass sheet 10 towards the curving mold 132 at the level of said peripheral form 10_EXT.

[0107] It is therefore understood that, unlike the example of embodiment in [Fig.2], the contact force is here applied below the glass sheet 10, i.e. at the level of the face supported by the pressing frame 131. In addition, the use of the suction device 251 makes it easier to remove the inner form 10_INT once the breaking has been carried out.

[0108] Fig. 7 schematically represents yet another example of an embodiment of a breaking system 350 in which the contact means comprise a suction device 351 configured similarly to the suction device 251 of Fig. 6.

[0109] In addition, the resistance means here comprise means for holding the peripheral shape 10_EXT against the bulging surface 133 (a priori therefore when the air suction means 134 are deactivated), said holding means 352 being distinct from the pressing frame 131.

[0110] For example, said holding means 352 may include pressing elements arranged around the periphery of the crowning mold 132 and configured to press the peripheral shape 10_EXT against the crowning surface 133 when the glass sheet 10 is in contact with said crowning surface 133 (and therefore when the pressing frame 131 is lowered relative to the crowning mold 132).

[0111] By way of illustration, and as shown in [Fig. 7], such pressing elements 352 can correspond to "L"-shaped arms. A first arm of each arm 352 has a movable end mounted for rotation on a side wall of the doming mold 132. Each arm 352 can thus pivot between two positions: - a first position called "opening" (represented by dotted lines on [Fig.7]), in which the pressing frame 131 has access to the curvature surface 133 in order to perform the pressing of the glass sheet 10, - a second position called "locking" (represented in solid lines on [Fig.7]), in which the second branch of the arm 352 is able to press the peripheral form 10_EXT against the bulging surface 133.

[0112] Regardless of the embodiment described above for the breaking system 150, 250, 350 with reference to Figures 2, 6, and 7, the resistance means may also include, in a more specific embodiment, said air suction means 134 as well as said air circulation means 135. It is understood that, depending on when said air suction means 134 are activated, the resulting suction at the level of the bending surface 133 can contribute to the resistance force. This is particularly the case if this suction is present as soon as the pressing frame 131 takes hold of the glass sheet 10 to lift it towards the bending mold 132.

[0113] The invention has been described so far considering the glass sheet 10 to be a primitive. However, these provisions are not limiting, and the invention also covers other embodiments in which the glass sheet 10 can be considered, prior to its introduction into the installation for putting into shape (and therefore a fortiori before the bending phase), to a piece of glass in a flat state already conformed to the dimensional characteristics of the glazing to be manufactured.

[0114] In these other modes, the inner shape 10_INT to be broken corresponds to an opening in the glazing intended for the implementation of a functionality, such as the implementation of an optical system such as a camera or lidar. Therefore, at the output of the forming installation, it is no longer the inner shape 10_INT that is recovered to manufacture the glazing, but the formed peripheral shape 10_EXT containing said opening.

[0115] Figure 8 schematically represents an example of an embodiment of a sheet of glass 10 in the planar state, shaped to the dimensions of a windshield. In this example, the inner shape 10_INT is intended for the integration of a lidar-type optical system, and the peripheral shape 10_EXT is complementary to said inner shape 10_INT.

[0116] In general, the description given above with reference to figures 2 to 4 and 6 to 7 applies similarly to these other embodiments (it is understood that, in the case where the objective is to obtain a peripheral shape 10_EXT shaped and having an opening defined by the inner shape 10_INT, there is no need to consider auxiliary cutting lines such as those described with reference to [Fig.5]).

[0117] Fig. 9 represents, in the form of a flowchart, a particular method of implementing a shaping process according to the invention, as carried out in a shaping installation according to the invention.

[0118] As illustrated by [Fig.9], the shaping process initially comprises a step E10 of heating the glass sheet 10. Said step E10 is implemented by the heating zone 110.

[0119] Once heated to the desired temperature, the shaping process includes a step E20 of conveying the glass sheet 10 from the heating zone 110 to the bending system 130. Said step E20 is implemented by the conveying device 120.

[0120] Subsequently, during a step E30 of the shaping process, the glass sheet 10 is lifted, at the level of the peripheral form 10_EXT, by the pressing frame 131 to be pressed against the doming surface 133 of the shaping mold 132.

[0121] Thanks to the contact means and the resistance means (and possibly, in addition, to the air suction means 134 and the air circulation means 135), the internal shape 10_INT is broken during a step E40.

[0122] In a step E50 of the shaping process, a portion POR_10 of the glass sheet 10 as supplied as input to the shaping installation is transferred towards the cooling system 140. It follows from the above that this portion POR_10 corresponds to the inner shape 10_INT or to the peripheral shape 10_EXT, therefore equipped with an opening according to the glazing to be manufactured.

[0123] Then, a cooling step E60 of said portion POR_10 is then implemented.

[0124] It should be noted that all or part of steps E10 to E60 of the forming process can be automated. For this purpose, the forming installation may include a processor and memory, for example read-only memory, readable by said processor. In addition, a computer program may be stored in said memory and include instructions which, when read by the processor, allow the various elements integrated into said forming installation (heating zone, conveying device, crowning system, breaking system, transfer system, cooling system) to be controlled / activated / regulated, so as to enable the execution of the forming process.

[0125] It is also noted that, within the framework of the present implementation of [Fig.9], the shaping process includes at least one breaking process defined by step E40.

[0126] Finally, the invention also relates to a method for manufacturing glazing, for example laminated glazing, for example semi-tempered or annealed glazing, or tempered (monolithic) glazing. The main steps of said manufacturing method are illustrated in [Fig. 10]. As can be seen, the manufacturing method includes a step F10 for shaping a sheet of glass. This step F10 is carried out according to any one of the embodiments of the shaping method.

[0127] Then, once the portion POR_10 has been shaped and cooled, the manufacturing process includes a step F20 of using said portion POR_10 to manufacture said glazing.

[0128] It should be noted that nothing excludes other modes of implementation of the manufacturing process in which the latter also includes, prior to the shaping step F10, a step of realizing at least said main cutting line TD_P, according to any known method, in particular by Bessel beam pulsed laser or by laser filamentation.

Claims

Demands

1. Breaking system (150, 250, 350) of an internal shape (10_INT) in a sheet of glass (10), said sheet of glass having at least one main cutting line (TD_P) separating the internal shape from at least one peripheral shape (10_EXT) complementary to said internal shape, said breaking system comprising: - contact means (151, 251, 351) configured to come into contact with the internal shape during a bending phase of the sheet of glass, so as to apply a contact force at the level of the internal shape, - resistance means (131, 352) configured to apply, at the level of said at least one peripheral shape and when said contact force is applied, a resistance force opposite to said contact force.

2. System (150, 250, 350) according to claim 1, wherein said at least one main cutting line (TD_P) is made by laser, in particular by Bessel beam pulsed laser or by laser filamentation.

3. System (150, 250, 350) according to claim 2, wherein said at least one main cutting line (TD_P) is made by means of a first pre-cutting phase by pulsed laser by Bessel beams or by laser filamentation, so as to generate discontinuous embrittlement in the mass of the glass, and a second propagation phase of said discontinuous embrittlement, for example implemented by CO2 laser.

4. System (150) according to any one of claims 1 to 3, wherein said bending phase is implemented by means of a bending system (130) comprising a pressing frame (131) and a bending mold (132) comprising a bending surface (133), the resistance means comprising the pressing frame dimensioned to lift the glass sheet towards the bending mold at the level of said at least one peripheral form, and the contact means comprising at least one element (151) having an extra thickness arranged fixedly on the bending surface to come into contact with the inner form when the glass sheet is lifted towards the bending mold.

5. System (250, 350) according to any one of claims 1 to 3, wherein said bending phase is implemented by means of a bending system (130) comprising a pressing frame (131) and a bending mold (132) comprising a bending surface (133), the contact means comprising a suction device (251, 351), for example by suction effect, configured to suction the inner shape when the glass sheet is held against the bending surface, said suction being carried out in a direction opposite to the direction in which the glass sheet is lifted by the pressing frame towards the bending mold.

6. System (250, 350) according to claim 5, wherein the resistance means comprise: - the pressing frame (131) dimensioned so as to lift the glass sheet towards the bending mold at the level of said at least one peripheral shape, or - means for holding said at least one peripheral shape against the bending surface, said holding means being separate from the pressing frame, such as, for example, pressing elements arranged at the periphery of the bending mold and configured to press said at least one peripheral shape against the bending surface when the glass sheet is in contact with said bending surface.

7. System (150, 250, 350) according to any one of claims 4 to 7, wherein the crowning system (130) further comprises air circulation means (135) at the crowning surface and air suction means (134) through said air circulation means, the resistance means comprising said air suction means and said air circulation means.

8. System (150, 250, 350) according to any one of claims 1 to 7, wherein the thickness of the glass sheet (10) is between 1mm and 5mm, preferably between 1.4mm and 2.6mm, for example equal to 2.1mm.

9. System (150, 250, 350) according to any one of claims 1 to 8, wherein said internal form (10_INT) is intended for the manufacture of glazing, such as automotive glazing of the windshield, canopy, side window or rear window type.

10. System (150, 250, 350) according to claim 9, wherein the glass sheet (10) also carries at least one auxiliary cutting line (TD_A) connecting at least one main cutting line to the edge of the glass sheet.

11. System (150, 250, 350) according to any one of claims 1 to 8, wherein the glass sheet (10) is, prior to the bending phase, shaped to the dimensions of a glazing intended to be manufactured from said glass sheet, such as, for example, automotive glazing of the windshield, canopy, side window or rear window type, and wherein breaking the internal shape (10_INT) defines an opening in the glass sheet, said opening being intended for the implementation of a functionality, such as, for example, the implementation of an optical system of the camera or lidar type.

12. A glass sheet (10) forming installation (INS_1) carrying at least one main cutting line (TD_P) separating an inner shape (10_INT) from at least one peripheral shape (10_EXT) complementary to said inner shape, said installation comprising a breaking system (150, 250, 350) according to any one of claims 1 to 11.

13. Method for breaking an internal shape (10_INT) in a sheet of glass (10), said sheet of glass having at least one main cutting line (TD_P) separating the internal shape from at least one peripheral shape (10_EXT) complementary to said internal shape, said method being implemented by a breaking system (150, 250, 350) according to any one of claims 1 to 11.

14. A method for shaping a sheet of glass (10) bearing at least one main cutting line (TD_P) separating an inner shape (10_INT) from at least one peripheral shape (10_EXT) complementary to said inner shape, said method being implemented by a shaping installation (INS_1) according to claim 12.

15. A method for manufacturing glazing, for example laminated glazing or tempered glazing, said manufacturing method comprising steps of: - shaping a sheet of glass (10) bearing at least one principal cutting line (TD_P) separating a shape

16.

17. internal (10_INT) of at least one peripheral shape (10_EXT) complementary to said internal shape, said shaping being carried out in accordance with a shaping process according to claim 14, - if the breaking system (150, 250, 350) conforms to any one of claims 9 to 10, use of the broken inner shape (10_INT) to manufacture said glazing, - if the breaking system (150, 250, 350) conforms to claim 11, use of the peripheral shape (10_EXT) to manufacture said glazing. Method according to claim 15, further comprising, before the shaping step, a step of producing at least said main cutting line (TD_P), in particular by Bessel beam pulsed laser or by laser filamentation. Glazing, in particular for motor vehicles, obtained by the manufacturing process of any one of claims 15 or 16.

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