Method and system for breaking an internal shape in a sheet of glass in its flat state

Abstract

Method and system for breaking an internal shape in a sheet of glass in the flat state. The invention relates to a method for breaking an internal shape (10_INT) in a sheet of glass (10) in the flat state, said method comprising the steps of: - making (E10) a cutting line (T_D) in the sheet of glass using a Bessel beam pulsed laser or laser filamentation, said cutting line delimiting the internal shape with respect to a peripheral shape (10_EXT) complementary to the internal shape, - generating (E20) a temperature gradient between the internal shape and the peripheral shape to break said internal shape. Figure for the abstract: Fig. 2

Description

Title of the invention: Method and system for breaking an internal shape in a sheet of glass in the flat state. Prior art

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

[0002] The invention relates more particularly to a method and system for breaking an internal shape in a sheet of glass in its flat state, as well as to a breaking system configured to implement such a method. The invention also relates to a method and system for shaping such a sheet of glass in which an internal shape has been broken, or at least a piece of glass corresponding to the broken internal shape, as well as a method and system for manufacturing glazing from one or more glazed elements thus shaped.

[0003] The invention finds a particularly advantageous, although by no means limiting, application in the cutting and shaping of glass sheets to manufacture laminated or tempered glazing, in particular automotive glazing, such as fixed panoramic roofs of the "canopy" type, windshields, side windows or rear windows.

[0004] Most automotive glazing is now manufactured so as to include an opening (orifice) intended for the implementation of a function, such as: passage of 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 an optical system of the camera or lidar type, etc.

[0005] These openings are traditionally made in the sheets of glass used in the composition of the glazing while these sheets are still in a flat state, that is to say before being shaped by curving in a shaping installation.

[0006] More specifically, an internal shape corresponding to said opening is broken in the glass by means of several successive operations, including in particular: - A cutting line (also called a "cut line") is drawn, corresponding to a superficial crack on the surface of the glass, and defining the inner shape within the glass sheet. This drawing is typically done using a glass cutter. - The inner shape is then separated from the glass sheet.

[0007] Several major drawbacks result from these operations, including: - very low mechanical resistance of the glass, particularly near the edge of the opening resulting from the breaking of the internal shape, - the formation of scales at the edge of the opening once the internal shape is broken.

[0008] Current techniques propose to mitigate the formation of flakes by shaping the edge of the opening, either before or after shaping the glass sheet. However, implementing this additional step complicates the glazing manufacturing process.

[0009] Moreover, the shaping does not improve the mechanical resistance of the glass, particularly in the vicinity of the edge of the opening, which limits the carrying out of subsequent operations after the manufacture of the glazing, such as encapsulation of the glazing or integration of mechanical and / or electronic components. Description of the invention

[0010] The present invention aims to remedy all or part of the drawbacks of the prior art, in particular those described above, by proposing a solution that makes it possible to break an internal shape in a sheet of glass in its flat state so that: - the edge of the resulting opening is not chipped, thus eliminating the need for subsequent edge shaping. In this way, the solution proposed by the invention makes it possible to manufacture glazing more efficiently, less complexly, and less expensively than prior art solutions. - the glazing intended for manufacture exhibits excellent mechanical stability.

[0011] To this end, and according to a first aspect, the invention relates to a method for breaking an internal shape in a sheet of glass in its flat state, said method comprising the steps of: - making a cutting line in the sheet of glass using a Bessel beam pulsed laser or laser filamentation, said cutting line delimiting the inner shape in relation to a peripheral shape complementary to the inner shape, - generation of a temperature gradient between the inner shape and the peripheral shape to break said inner shape.

[0012] The use of laser filamentation allows, once the internal shape has been broken, the obtaining of a filamentated edge, and therefore, in particular, a straight edge. A similar appearance is obtained when a Bessel beam pulsed laser is used. This result is particularly advantageous insofar as it also contributes to giving said edge excellent mechanical stability, useful for achieving efficiently (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.

[0013] More particularly, and as has been measured, the edge obtained in accordance with such arrangements has average roughness values ​​between 0.01 pm and 10 pm, in particular between 0.1 pm and 2 pm.

[0014] An additional advantage resulting from obtaining such a filament edge is the total elimination of the need to shape this edge.

[0015] The generation of said temperature gradient, for its part, makes it possible to create a relative displacement of the inner shape with respect to the peripheral shape, so as to create a separation (dissociation) between these two elements. This relative displacement is particularly advantageous insofar as the separation (dissociation) occurs without generating scales at the edge of the opening resulting from the rupture of the inner shape.

[0016] In particular embodiments, the breaking process may further include one or more of the following characteristics, taken individually or in all technically possible combinations.

[0017] In particular embodiments, the execution of the cutting line comprises: - a pre-cutting of the internal shape by pulsed laser using Bessel beams or by laser filamentation, so as to generate discontinuous embrittlement within the mass of the glass, and - a propagation of said discontinuous embrittlement, for example implemented by CO2 laser.

[0018] Achieving such a propagation of said discontinuous embrittlement makes it possible to further facilitate the subsequent breaking of the internal shape.

[0019] In particular embodiments, the generation of the temperature gradient comprises: - cooling of the internal shape, to generate a temperature difference between the internal shape and the peripheral shape within a given range, for example between 20°C and 100°C, and / or - heating of the peripheral shape, to generate a temperature difference between the inner shape and the peripheral shape within a given range, for example between 20°C and 200°C, in particular of the order of 100°C.

[0020] In specific embodiments: - Cooling is achieved by pressing at least one part, called a cooling part, against the inner shape, or by blowing a refrigerated gas, such as air, onto the inner shape using a nozzle, or by thermoelectric cooling at the level of the internal shape by means of at least one Peltier element, and / or - heating is implemented by pressing against the peripheral shape of at least one part, called the heating part, or by blowing a heated gas, such as air, at the level of the peripheral shape by means of a nozzle, or by thermoelectric heating at the level of the peripheral shape by means of at least one Peltier element, or by radiation at the level of the peripheral shape by means of at least one heating resistance.

[0021] In particular embodiments, the thickness of the glass sheet is between 1mm and 5 mm, preferably between 1.4 mm and 2.6 mm, for example equal to 2.1 mm.

[0022] In particular embodiments, the glass sheet is 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 the opening resulting from breaking the internal shape is intended for the implementation of a functionality, such as, for example, the implementation of an optical system of the camera or lidar type.

[0023] In particular embodiments, the internal shape is intended for the manufacture of glazing, such as for example automotive glazing of the windshield, canopy, side window or rear window type.

[0024] According to a second aspect, the invention relates to a method of shaping a sheet of glass in which an internal shape has been broken according to a breaking process according to the invention or of an internal shape broken according to a breaking process according to the invention.

[0025] In particular embodiments, the shaping process may further comprise one or more of the following characteristics, taken individually or in all technically possible combinations.

[0026] In particular embodiments, the shaping is applied to a sheet of glass in which an internal shape has been broken in accordance with a breaking process according to the invention, said shaping comprising a step of curving the sheet of glass by pressing against a curving mold, as well as, when the sheet of glass is pressed against the curving mold, an additional step of pressing the face of the sheet of glass opposite to the face pressed against the curving mold, the additional pressing being carried out in the direction of the curving mold and at the level of the edge of said opening.

[0027] Such additional pressing advantageously allows the edge of the opening to be compressed, which contributes to the robustness (i.e., mechanical resistance) of the sheet of glass fitted with the opening, and therefore ultimately also the robustness of the glazing intended to be manufactured.

[0028] By way of non-limiting example, the compressive stresses obtained in the vicinity of the opening can be between 40 MPa and 60 MPa.

[0029] In addition to these advantageous aspects in terms of robustness, the additional pressing makes it possible to maintain the edge of the opening during the curving stage. In this way, the edge of the opening does not deform, which contributes to obtaining excellent optical quality in reflection near the edge of the opening. In particular, this helps to avoid the appearance of a "volcano effect" (i.e. the edge of the opening tends to counter-curve, that is to say, to protrude from the curved surface on the convex side of the glazing; viewed from outside a vehicle, the edge of the opening therefore takes on a slight volcano shape; this displacement on the order of a few tenths of a millimeter is very visible in reflection).

[0030] In particular embodiments, the additional pressing is carried out over a distance of between 2 mm and 2 cm from the edge of said opening.

[0031] According to a third aspect, the invention relates to a method for manufacturing glazing, for example laminated glazing or tempered glazing, from: - at least one sheet of glass shaped according to the invention, or - at least one internal shape shaped according to the invention.

[0032] According to a fourth aspect, the invention relates to a system for breaking an internal shape in a sheet of glass comprising means configured to implement a breaking process according to the invention.

[0033] According to a fifth aspect, the invention relates to a glass sheet forming installation in which an internal shape has been broken according to a breaking process according to the invention, the forming installation comprising: - means configured to implement a forming process according to the particular modes described above in which additional pressing is carried out, and / or - means configured to support the edge of the opening during the transfer of the glass sheet between a bending system and a cooling system both integrated into the forming installation.

[0034] According to a sixth aspect, the invention relates to a system for manufacturing glazing, for example laminated glazing or tempered glazing, comprising means configured to implement a manufacturing process according to the invention.

[0035] According to a seventh 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

[0036] 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:

[0037] [Fig-1] the [Fig. 1], schematically represents a particular embodiment of a breaking system according to the invention;

[0038] [Fig.2] [Fig.2] represents, in the form of a flowchart, a particular mode implementation of a breaking process according to the invention, as executed by the breaking system of [Fig.1];

[0039] [Fig.3] [Fig.3] schematically represents an example of the realization of a sheet of glass in a flat state, shaped to the dimensions of a windshield, and having an internal shape intended to be broken during the implementation of the process of [Fig.2];

[0040] [Fig.4] [Fig.4] schematically represents an example of the realization of a line of cutting in a sheet of glass using a laser filamentation technique;

[0041] [Fig. 5] [Fig. 5] schematically represents, from several views, an example of making a cut line in a sheet of glass using a Bessel beam pulsed laser technique;

[0042] [Fig.6] [Fig.6] schematically represents an example of plating a part cooling against an internal shape intended to be broken during the implementation of the process of [Fig.2];

[0043] [Fig.7] [Fig.7] schematically represents an example of plating a part heating against a peripheral form complementary to an internal form intended to be broken during the implementation of the process of [Fig.2];

[0044] [Fig.8] [Fig.8] schematically represents a particular embodiment of a shaping installation according to the invention;

[0045] [Fig.9] [Fig.9] represents, in the form of a flowchart, a particular mode of implementation of a shaping process according to the invention, as carried out by the shaping installation of [Fig.8];

[0046] [Fig. 10] [Fig. 10] represents, in a close-up view, a specific example of the realization of a crowning system and additional pressing means belonging to the shaping installation of [Fig. 8];

[0047] [Fig. 11] [Fig. 11] 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

[0048] Fig. 1 schematically represents, in its environment, a particular embodiment of a SYS_R breaking system according to the invention.

[0049] As will now be described, said SYS_R breaking system comprises means configured to break an internal shape 10_INT in a sheet of glass 10 in the planar state, by implementing a breaking process according to the invention.

[0050] Said glass sheet 10 corresponds to a plate formed from a transparent material, such as mineral glass, such as soda-lime glass, aluminosilicate, or borosilicate.

[0051] It should be noted that, within the framework of the present invention, and as described in more detail later, the glass sheet 10 is intended to be introduced in a flat state and provided with an opening corresponding to the internal shape 10_INF into a forming installation. It follows in particular from these provisions that the internal shape 10_INF is broken in the glass sheet 10 prior to its introduction into the forming installation.

[0052] For the remainder of this description, the glass sheet 10 is considered, without limitation, to be a flat piece of glass conforming to the dimensions of a glazing unit to be manufactured, before its introduction into the shaping installation. Put another way, said glazing unit is intended to be manufactured from said glass sheet 10 once an opening has been made in it by breaking the internal form 10_INT and it has been shaped.

[0053] For the remainder of the description, it is considered more specifically that the glass sheet 10 is intended, after breaking and shaping, for the manufacture of laminated glazing to equip a motor vehicle, such as a car.

[0054] For example, in the present embodiment, said glazing corresponds to an automobile windshield. In other words, the dimensional characteristics of the glass sheet 10 are those of the windshield to be manufactured. Moreover, the opening resulting from the breaking of the internal shape 10_INT is intended for the implementation of a function, such as, for example, the implementation of an optical system such as a camera or lidar.

[0055] However, considering such a type of automotive 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 glass sheet 10. Thus, it could, for example, be glazing intended for the vehicle's roof, such as a canopy, side windows, or even a rear window. It could also be tempered (monolithic) glazing.

[0056] The invention is not further limited in terms of functionality implemented via said opening. By way of illustration, this functionality may also correspond to a passage for the cables of an antenna fixed to a glass roof, a passage for the rear wiper shaft for a rear window, a possible passage for roof bar fixing shafts in a glass roof, etc.

[0057] Furthermore, and more generally, there are no limitations on the use that can be made of the glazing thus obtained from the glass sheet 10 in which the internal shape 10_INT is broken and which is subsequently shaped. In particular, this use is not restricted to the automotive application field and can concern other application areas (e.g., glazing for a dwelling).

[0058] The invention is also described herein in the context of breaking and shaping for a single sheet of glass 10. These considerations are not, however, limiting of the invention, it being understood that the operations described below can be iterated for each of a plurality of sheets of glass, such as for example a second sheet of glass used to manufacture laminated glazing.

[0059] In the present embodiment, the glass sheet 10 has a thickness between 1mm and 5mm, preferably between 1.4mm and 2.6mm, for example equal to 2.1mm.

[0060] 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.

[0061] Fig. 2 represents, in flowchart form, a particular method of implementing said breaking process.

[0062] As illustrated by [Fig.2], the breaking process includes a step E10 of making a cutting line T_D in the glass sheet 10.

[0063] Said cutting line T_D delimits the inner shape 10_INT vis-à-vis a peripheral shape 10_EXT complementary to said inner shape 10_INT, as shown in [Fig.3] by way of non-limiting example.

[0064] Said step E10 is implemented using a laser 110, the latter being integrated into the SYS_R breaking system, as illustrated by [Fig. 1]. More particularly, step E10 is implemented using a Bessel beam pulsed laser or a laser filamentation laser.

[0065] It is important to note that the cutting line T_D does not in itself constitute a break in the internal shape 10_INT, but only a weakening (within the mass of the glass) of its contour. Put another way, the cutting line T_D does not effectively separate the internal shape 10_INT from the rest of the glass sheet 10.

[0066] In a known manner, the use of Bessel beam pulsed laser techniques or laser filamentation makes it possible to generate, in the mass of the glass sheet 10, substantially rectilinear "fragilities" which, ideally, extend between the two main faces of said sheet.

[0067] More specifically, and as schematically illustrated in [Fig. 4], 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. 4]), 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 cutting line T_D.The very high cutting precision of laser filamentation makes it a particularly suitable method for thin glass.

[0068] 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 on the order of 10 mm. In addition, a Bessel beam is characterized by its ability to propagate without diffraction or dispersion over a certain distance. This means that 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 the Bessel beams take the form of channels, as is schematically illustrated, for example, in [Fig.5] which includes: - a first view 5A representing, in cross-section of the glass sheet 10, channels C_LAS_B spaced every 5 pm, - a second view 5B representing, in top view, said channels C_LAS_B. The joining of these discontinuous channels C_LAS_B also forms a "weakening curtain" whose projection onto the main faces of the sheet determines the cutting line T_D.

[0069] It follows from the above that the embrittling 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.

[0070] More specifically, the generation of such discontinuous embrittlement can correspond, in the execution of the T_D cutting line, 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. The fact of carrying out such a second phase makes it even easier to subsequently break down the internal shape 10_INT.

[0071] Once the cutting line T_D is made, and as illustrated by [Fig.2], the breaking process includes a step E20 of generating a temperature gradient between the inner shape 10_INT and the peripheral shape 10_EXT to break said inner shape 10_INT.

[0072] Said step E20 is implemented using means 120 for generating said temperature gradient, the latter being integrated into the SYS_R breaking system, as illustrated by [Fig.1].

[0073] In its general principle, the generation of said temperature gradient advantageously makes it possible to create a relative displacement of the inner shape 10_INT with respect to the peripheral shape 10_EXT, so as to create a separation (dissociation) between these two elements.

[0074] According to a more particular embodiment, the temperature gradient generation step E20 involves cooling the inner shape 10_INT. This cooling is implemented to generate a temperature difference between the inner shape 10_INT and the peripheral shape 10_EXT within a given range, for example, between 20°C and 100°C. Performing such cooling allows for a local contraction of the inner shape 10_INT, i.e., a reduction in its size, particularly at the cutting line T_D, thus causing its separation from the peripheral shape 10_EXT.

[0075] Such cooling is for example implemented by pressing against the inner shape 10_INT at least one part, called cooling part 121, integrated into the means 120 for generating the temperature gradient.

[0076] Figure 6 schematically represents an example of plating a cooling piece 121 against the inner form 10_INT. In this example, the cooling piece 121 is a plate whose dimensions (measured in the plane of the glass sheet 10) are identical to those of the inner form 10_INT, so that it can be superimposed on the latter (the piece 121 is shown in hatching on Figure 6).

[0077] The cooling of the cooling piece 121 can be implemented according to any technique known to the person skilled in the art. For example, the cooling piece 121 can be connected to a pipe (not shown in the figures) for conveying a chilled gas, such as air, into the piece 121. According to another example, the cooling piece 121 can be cooled prior to plating against the inner form 10_INT, for example by being placed in a cooling chamber.

[0078] No limitations are attached to the means for achieving the pressing of the cooling part 121 against the inner form 10_INT. By way of non-limiting example, these means may include a robotic arm.

[0079] Moreover, considering a single cooling piece 121 such as that illustrated in [Fig.6] is only one variant of implementation of the invention, other variants may still be envisaged.

[0080] For example, the dimensions (measured in the plane of the glass sheet 10) of the cooling piece 121 may be substantially smaller or larger than those of the inner shape 10_INT.

[0081] In addition or as an alternative, two cooling pieces, i.e. a first cooling piece and a second cooling piece, may be used. The first cooling piece is then pressed against the inner form 10_INT at the level of a first face of the glass sheet 10, and the second cooling piece is pressed against the inner form 10_INT at the level of a second face of the glass sheet 10, it being understood that said first and second faces are opposite each other.

[0082] Furthermore, there is nothing to preclude considering a cooling method other than a plate. For example, cooling can be achieved by blowing a refrigerated gas, such as air, through a nozzle at the inner shape 10_INT, or by thermoelectric cooling of the inner shape 10_INT using at least one Peltier element.

[0083] According to another, more specific embodiment, the temperature gradient generation step E20 involves heating the peripheral shape 10_EXT. This heating is implemented to generate a temperature difference between the inner shape 10_INT and the peripheral shape 10_EXT within a given range, for example, between 20°C and 200°C, in particular on the order of 100°C. Performing such heating allows for the generation of a local expansion of the peripheral shape 10_EXT, that is to say, an increase in its size, particularly at the cutting line T_D, thus causing its separation from the inner shape 10_INT.

[0084] Such heating is for example implemented by pressing against the peripheral form 10_EXT at least one part, called heating part 122, integrated into the means 120 for generating the temperature gradient.

[0085] Figure 7 schematically represents an example of a heating element 122 being attached to the peripheral form 10_EXT. In this example, the heating element 122 is a plate whose dimensions (measured in the plane of the glass sheet 10) are identical to those of the peripheral form 10_EXT, so that it can be superimposed on the latter.

[0086] Nothing precludes considering a heating method other than a plate. For example, heating can be achieved by blowing heated gas, such as air, through a nozzle at the peripheral form 10_EXT, or by thermoelectric heating at the peripheral form 10_EXT using at least one Peltier element, or by radiation at the peripheral form 10_EXT using at least one heating element.

[0087] In general, all the technical characteristics and variants described above in the context of cooling the inner shape 10_INT can be considered, with appropriate adaptation, in the context of heating the peripheral shape 10_EXT (heating methods, plating means, number of parts, dimensions, use of at least one blow nozzle).

[0088] It should be noted that the methods in which, on the one hand, the inner form 10_INT is cooled, and, on the other hand, the outer form 10_EXT is heated, have been described separately above. These provisions, however, do not limit the invention, which also covers the case where these methods are combined.

[0089] It should be noted that once the inner form 10_INT is broken, it can be removed using any method known to a person skilled in the art. For example, it can be vacuumed up using a suction device. Alternatively, after breaking, the inner form 10_INT can fall (by gravity) and be collected by a collection device.

[0090] Once the breaking process is complete, the peripheral shape 10_EXT, still in a planar state, can then be shaped.

[0091] Fig. 8 schematically represents, in its environment, a particular embodiment of an INS_MF shaping installation according to the invention.

[0092] Said shaping installation INS_MF includes means configured to shape the peripheral shape 10_EXT, by implementing a shaping process according to the invention.

[0093] Fig. 9 represents, in flowchart form, a particular method of implementing said shaping process.

[0094] As illustrated by [Fig.9], the forming process includes a step F10 of heating the peripheral form 10_EXT. This step F10 is implemented by a heating zone 210 integrated into the forming installation INS_MF.

[0095] Said heating zone 210 can be conventionally implemented by a furnace, preferably of the tunnel type, through which the peripheral form 10_EXT is transported by a conveying device 220 also integrated into the forming installation INS_MF. The conveying device 220 corresponds more particularly here to a series of straight rollers aligned in a plane to achieve a horizontal displacement of the peripheral shape 10_EXT. The peripheral shape 10_EXT is thus transported along a horizontal rectilinear path contained within this plane. However, considering such rollers is only one variant of the invention's implementation, and nothing precludes considering other variants, such as a conveyor belt.

[0096] Inside the heating zone 210, the peripheral shape 10_EXT is brought to a softening temperature which is preferably between 600°C (degrees Celsius) and 700°C.

[0097] The forming process also includes a step F20 of crowning the peripheral shape 10_EXT. This step F20 is implemented by a crowning system 230 integrated into the forming installation INS_MF.

[0098] The bulging system 230 is arranged in the immediate vicinity of the outlet of the heating zone 210. More particularly, the bulging system 230 is configured according to a bulging station.

[0099] To this end, and in the present embodiment, the crowning system 230 comprises a pressing frame 231 capable of lifting the peripheral form 10_EXT and pressing it against a crowning mold 232, thus giving it the desired shape. More particularly, the crowning mold 232 comprises a crowning surface 233 having said desired shape, against which the softened peripheral form 10_EXT is pressed and then held by means of air suction means 234 (example: vacuum pump) capable of generating suction through air circulation means at the level of the crowning surface 233 (example: channels passing through the crowning surface 233).

[0100] According to a more particular embodiment, the pressing frame 231 and / or the doming mold 232 comprise heating means (not shown in the figures). Such heating means are advantageously configured to regulate the temperature of the peripheral form 10_EXT (and more particularly the edge of the peripheral form 10_EXT) after it exits the heating zone 210, so that the shaping can be carried out at a predetermined temperature.

[0101] It should be noted that the crowning mold 232 can either be configured to be mobile in vertical translation (i.e., up / down movements of the crowning mold 232 relative to the conveying device 220) or remain fixed. These arrangements have an impact, once the crowning has taken place, on the kinematics of said crowning mold 232 and / or of a transfer system 250 integrated into the INS_MF forming installation as illustrated in [Fig. 1]. In particular, once the crowning has taken place, the gap between the crowning mold 232 and the conveying device 220 must be sufficient to allow a collection frame 251 belonging to the transfer system 250 to be positioned appropriately (i.e., below the doming mold 232) in order to collect the shaped peripheral shape 10_EXT (collection is carried out by dropping the peripheral shape 10_EXT onto the collection frame 251).

[0102] In addition, the collection frame 251 may optionally include heating means configured to finely control the temperature of the peripheral shape 10_EXT (and more particularly the edge of the peripheral shape 10_EXT) during its transfer.

[0103] The shaping process also includes, when the peripheral shape 10_EXT is pressed against the doming mold 232 (i.e. when step F20 is performed), an additional pressing step F30 of the face of the peripheral shape 10_EXT opposite to the face pressed against the doming mold 232. Said step F30 is implemented by additional pressing means 240 integrated into the shaping installation INS_MF.

[0104] The additional pressing is carried out in the direction of the doming mold 232 and at the level of the edge of the opening resulting from the breaking of the internal shape 10_INT.

[0105] Fig. 10 represents, in close-up view, a specific example of the implementation of the crowning system 230 and the additional pressing means 240, during the execution of step F30.

[0106] In the example of [Fig. 10], the additional pressing means 240 correspond to an additional pressing device 240 comprising a body 241 connected to an arm 242.

[0107] Said body 241 comprises a base 241_1 to which side walls 241_2 are attached. Each of said side walls 241_2 is provided, at its end opposite the base 241_1, with a support 241_3 whose dimensions are adjusted to provide additional pressure at the edge of the opening over a determined distance. This distance is, for example, between 2 mm and 2 cm from the edge of said opening.

[0108] In this embodiment of [Fig. 10], said arm 242 is connected to the pressing frame 231, so as to be fixed to it in vertical translation. Consequently, the length of the arm 242 is adjusted so that the supports 241_3 come into contact with the peripheral form 10_EXT to perform the additional pressing function when said peripheral form 10_EXT is itself pressed against the doming mold 232 by the pressing frame 231.

[0109] However, considering an additional pressing device 240 such as that described with reference to [Fig. 10] does not constitute a limitation of the invention. In particular, nothing excludes the possibility that the arm 242 is not connected to the pressing frame 231 and can be moved independently of the movement of said pressing frame 231 (example: the arm 242 is a robotic arm).

[0110] It should also be noted that, for the purposes of the present invention, the implementation of step F30 is optional. The additional pressing carried out during step F30 advantageously compresses the edge of the opening, which contributes to the robustness (i.e., mechanical resistance) of the peripheral form 10_EXT, and therefore ultimately also to the robustness of the glazing to be manufactured.

[0111] By way of non-limiting example, the compressive stresses obtained in the vicinity of the opening can be between 40 MPa and 60 MPa.

[0112] In addition to these advantageous aspects in terms of robustness, the execution of step F30 also makes it possible to maintain the edge of the aperture during the curvature step F20. In this way, the edge of the aperture does not deform, which contributes to obtaining excellent optical quality in reflection near the edge of the aperture. In particular, this helps to avoid the appearance of a "volcano effect" (i.e. the edge of the aperture tends to counter-curve, that is to say, to protrude from the curved surface on the convex side of the glazing; viewed from outside a vehicle, the edge of the aperture therefore takes on a slight volcano shape; this displacement on the order of a few tenths of a millimeter is very visible in reflection).

[0113] Once the peripheral shape 10_EXT is curved, it is transferred to a cooling system 260 integrated into the forming installation INS_MF by the transfer system 250, during a step F40 of the forming process.

[0114] As described previously, the transfer system 250 includes a collection frame 251 configured to collect the peripheral shape 10_EXT after it has been domed. To do this, while it is still held against the doming mold 232, the suction means 234 are deactivated, so that the peripheral shape 10_EXT can be released onto the collection frame 251.

[0115] The transfer system 250 also includes a displacement shuttle 252 configured to move the collection frame 251 between the bulging system 230 and the cooling system 260. To do this, the collection frame 251 is attached to the shuttle 252 so as to be bound in displacement, arranged at one end of the shuttle 252, as shown illustratively in [Fig.8].

[0116] The transfer system 250 also includes a transfer hood 253 configured to collect, by suction, the peripheral shape 10_EXT on the collection frame 251 and deposit it on a downstream part of the conveying device 220 responsible for conveying it to the cooling system 260. The movements of the collection hood 253 are, for example, carried out by means of a robotic arm connected to the latter.

[0117] Optionally, the transfer system 250 may also include means 254 configured to support the edge of the opening during the implementation of step F40.

[0118] No limitations are attached to the configuration of such support means 254. For example, and as illustrated by [Fig. 8], said support means 254 can be configured in a manner (substantially) identical to the additional pressing device 240 described with reference to [Fig. 10].

[0119] Similar to what has been mentioned above, the support means 254 advantageously allow the edge of the aperture to be held during the F40 transfer step, which helps to prevent the edge from deforming but also to obtain excellent optical quality in reflection near the edge.

[0120] The shaping process also includes a step F50 for cooling the peripheral shape 10_EXT. This step F50 is implemented by the cooling system 260.

[0121] Within the cooling system 260, the peripheral shape 10_EXT is rigidified, fixed, by the effect of forced general cooling applied to it. This cooling makes it possible to reduce the temperature of the peripheral shape 10_EXT sufficiently so that, when it leaves the general cooling system 260, it retains a shape as close as possible to the shape obtained by the curvature system 230.

[0122] 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.

[0123] It should be noted that all or part of steps E10 and E20 of the breaking process, as well as all or part of steps F10 to F50 of the forming process, can be automated. For this purpose, the breaking system SYS_R (respectively the forming unit INS_MF) may include a processor and memory, for example read-only memory, readable by said processor.In addition, a computer program can be stored in said memory and include instructions which, when read by the processor, allow the various elements integrated into said breaking system SYS_R to be controlled / activated / regulated, in particular the laser 110 and the means 120 for generating the temperature gradient, so as to allow the execution of the breaking process (respectively the various elements integrated into said shaping installation INS_MF, in particular the heating zone 210, the conveying device 220, the crowning system 230, the additional pressing means 240, the transfer system 250, the cooling system 260, so as to allow the execution of the shaping process).

[0124] Furthermore, the invention has been described so far by considering that the glass sheet 10 corresponds, before the breaking of the internal form 10_INT, to a piece of glass in a flat state conforming to the dimensions of a glazing unit intended to be manufactured. These provisions are not limiting to the invention, which also covers other embodiments in which the internal form 10_INT to be broken is intended for the manufacture of glazing, such as, for example, automotive glazing of the windshield, canopy, side window, or rear window type.

[0125] Thus, in these other modes, the glass sheet 10 can correspond to a primitive having dimensions greater than those of the glazing intended to be manufactured and it is the internal shape 10_INT which is introduced into the shaping installation INS_MF after its breaking.

[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. 11]. As can be seen, the manufacturing method includes a step G10 consisting of taking at least one sheet of glass shaped after an internal form has been broken in it as described above, or taking at least one internal form broken in a sheet of glass and shaped.

[0127] Then, the manufacturing process includes a step G20 of using said at least one shaped sheet of glass or said at least one shaped internal form to manufacture said glazing.

Claims

Demands

1. A method for breaking an internal shape (10_INT) in a sheet of glass (10) in the planar state, said method comprising steps of: - making (E10) a cutting line (T_D) in the sheet of glass using a Bessel beam pulsed laser or laser filamentation, said cutting line delimiting the internal shape with respect to a peripheral shape (10_EXT) complementary to the internal shape, - generating (E20) a temperature gradient between the internal shape and the peripheral shape to break said internal shape.

2. Method according to claim 1, wherein the realization (E10) of the cutting line (T_D) comprises: - a pre-cutting of the inner shape by pulsed laser by Bessel beams or by laser filamentation, so as to generate discontinuous embrittlement in the mass of the glass, and - a propagation of said discontinuous embrittlement, for example implemented by CO2 laser.

3. A method according to any one of claims 1 to 2, wherein the generation (E20) of the temperature gradient comprises: - a cooling of the inner shape, to generate a temperature difference between the inner shape and the peripheral shape within a given range, for example between 20°C and 100°C, and / or - a heating of the peripheral shape, to generate a temperature difference between the inner shape and the peripheral shape within a given range, for example between 20°C and 200°C, in particular of the order of 100°C.

4. A method according to claim 3, wherein: - cooling is achieved by pressing at least one part, referred to as the cooling part (121), against the inner shape, or by blowing a refrigerated gas, such as air, onto the inner shape by means of a nozzle, or by thermoelectric cooling of the inner shape by means of at least one Peltier element, and / or - heating is implemented by pressing against the peripheral shape of at least one part, called heating part (122), or by blowing a heated gas, such as air, at the level of the peripheral shape by means of a nozzle, or by thermoelectric heating at the level of the peripheral shape by means of at least one Peltier element, or by radiation at the level of the peripheral shape by means of at least one heating resistance.

5. A method according to any one of claims 1 to 4, wherein the thickness of the glass sheet (10) is between 1 mm and 5 mm, preferably between 1.4 mm and 2.6 mm, for example equal to 2.1 mm.

6. A method according to any one of claims 1 to 5, wherein the glass sheet (10) is 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 the opening resulting from breaking the internal shape is intended for the implementation of a functionality, such as, for example, the implementation of an optical system of the camera or lidar type.

7. A method according to any one of claims 1 to 5, wherein the 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.

8. A method for shaping a sheet of glass (10) in which an internal shape (10_INT) has been broken according to a breaking method according to claim 6 or an internal shape (10_INT) broken according to a breaking method according to claim 7.

9. A method according to claim 8, wherein the shaping is applied to a sheet of glass in which an internal shape has been broken according to a breaking process according to claim 6, said shaping comprising a bending step (F20) of the glass sheet by pressing it against a bending mold (232), and, when the glass sheet is pressed against the bending mold, an additional pressing step (F30) of the face of the glass sheet opposite the face pressed against the bending mold, the additional pressing being carried out towards the doming mold and at the level of the edge of said opening.

10. A method according to claim 9, wherein the additional pressing is carried out over a distance of between 2 mm and 2 cm from the edge of said opening.

11. A method for manufacturing glazing, for example laminated glazing or tempered glazing, from: - at least one sheet of glass shaped according to any one of claims 8 to 10, or - at least one internal form shaped according to claim Q

12. o. System for breaking an internal shape (10_INT) in a sheet of glass (10) comprising means configured to implement a breaking process according to any one of claims 1 to 7.

13. A glass sheet (10) forming installation (INS_MF) in which an internal shape (10_INT) has been broken according to a breaking process according to claim 6, the forming installation comprising: - means configured to implement a forming process according to any one of claims 9 to 10, and / or - means configured to support the edge of the opening during the transfer of the glass sheet between a bending system and a cooling system both integrated into the forming installation.

14. A system for manufacturing glazing, for example laminated glazing or tempered glazing, comprising means configured to implement a manufacturing process according to claim 11.

15. Glazing, in particular for motor vehicles, obtained by the manufacturing process of claim 11.

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