Machined glass sheet and associated machining process

Abstract

Machined glass sheet and associated machining method The invention relates to a glass sheet (100) comprising two main faces, a first main face (110) and a second main face (120), opposite each other and separated by an edge (130). Said edge comprises, on at least part of the periphery of the glass sheet: - a first convex curved part (131) connected to the first main face, - a second convex curved part (132) connected to the second main face, - a flat part (133) connecting said first and second curved parts together, the intersection between the flat part and a curved part being formed, in a cross-section of the glass sheet, by a single point. Figure for abstract: Fig. 4

Description

Title of the invention: Machined glass sheet and associated machining method Prior art

[0001] The present invention belongs to the general field of glazing manufacturing. It relates more particularly to a glass sheet machined at its edge and to a machining method for obtaining such a glass sheet. It also relates to a monolithic or laminated glazing comprising such a glass sheet, as well as a glazed assembly comprising a laminated glazing thus produced and cooperating with a finishing and / or sealing joint. The invention finds a particularly advantageous, although in no way limiting, application in the automotive field, in particular for the production of windshields.

[0002] Conventionally, the glass sheets used to produce glazing, for example in the automotive sector as windshields, rear windows, side windows or glass roofs, are machined (or even “shaped”) at their edge.

[0003] Such machining is carried out so that the edge has a rounded profile, thus avoiding the presence of sharp edges between the main faces of the glass sheet and the edge. This makes it possible in particular to facilitate the handling of the glass sheet, but also to more easily bond a finishing and / or sealing joint while preventing the latter from tearing.

[0004] It should be noted that by "main faces", reference is conventionally made in the present description to the faces of the glass sheet having the largest surface areas.

[0005] The machining in question is carried out, in a manner known per se, by means of a grinding wheel. This grinding wheel is typically made of steel and generally takes the form of a cylinder provided on its edge (i.e. on the surface parallel to the axis of rotation of the cylinder) with a groove provided with an abrasive surface. The abrasive nature of the surface of the groove is obtained by means of diamond particles attached to said surface.

[0006] In practice, the machining of a glass sheet is carried out by inserting the latter by the edge into the groove while the grinding wheel is rotating. This insertion is carried out until reaching the bottom of the abrasive surface (i.e. until the end of the abrasive surface), the latter being shaped so that once the bottom is reached, the edge of the glass sheet actually has the expected rounded shape.

[0007] It is therefore understood that the expected shape of the slice results from the fact that it is abraded by coming to fit, by insertion, the surface of the groove. Also said otherwise, it is the geometry of the groove surface that determines the final shape of the glass sheet slice.

[0008] [Fig. 1] schematically represents an exemplary embodiment of a grinding wheel 20 for machining the edge 13 of a glass sheet 10 as is known in the prior art. [Fig. 1] corresponds more particularly to a close-up partial view along a cross-section of the glass sheet 10, before the latter is machined.

[0009] The glass sheet 10 comprises two main faces, a first main face 11 (for example intended to be oriented towards an external environment) and a second main face 12 (for example intended to be oriented towards an internal environment). The two main faces 11, 12 are opposite and separated by the edge 13. It should be noted that before machining, the edge 13 is flat and orthogonal to the main faces 11, 12 (the glass sheet 10 resulting for example from a cutting operation in a larger glass plate).

[0010] In this example, the glass sheet 10 has a thickness equal to 2.1 mm and is shown at the start of its insertion, by the edge 13, into a groove 21 of a grinding wheel 20 (only a part of the grinding wheel 20 is shown here due to the close-up partial view). This configuration at the start of insertion into the groove 21 is more particularly called “initial machining configuration” in the remainder of the description, and is characterized in this example by the contacting of the joining edges between the edge 13 and the two main faces 11, 12 with the surface of the groove 21, it being understood that the glass sheet 10 extends perpendicular to the edge of the grinding wheel 20.

[0011] The groove 21 has a concave rounded shape (i.e. the rounded shape is oriented towards the inside of the grinding wheel 20), and its surface is provided with diamond particles (not shown in [Fig.l]) suitable for machining the glass sheet 10. More particularly, in the example of [Fig.l], the geometric shape of the surface of the groove 21 corresponds to an arc of a circle whose center is indicated by the reference C_21 and whose radius is 1 mm.

[0012] The distance H_21 separating the edge 13 from the apex of the arc of a circle is called the “machining height” in the remainder of the description, and is 1.1 mm in this embodiment. It is noted that the groove 21 is connected to edges 22, 23 of the grinding wheel (these edges 22, 23 forming part of the periphery of the grinding wheel 20) by rounded surfaces 24, 25 also corresponding to arcs of a circle whose respective centers are indicated by the references C_24, C_25 and whose respective radii are 2.1 mm.

[0013] [Fig. 2] schematically represents a glazed assembly 30 according to the state of the art, comprising a laminated glazing 40, and used as a windshield of a motor vehicle, the glass sheets of said glazing being machined in accordance with the provisions described with reference to [Fig.l].

[0014] The glazing 40 comprises two sheets of glass, an inner sheet of glass 41 (i.e. a sheet of glass oriented so as to face the interior of the vehicle) and an outer sheet of glass 42 (i.e. a sheet of glass oriented so as to face the environment external to the vehicle). The inner sheet 41 (respectively the outer sheet 42) comprises an inner main face 41_I interfacing with the interior of the vehicle, also called face F4 (respectively an outer main face 42_E interfacing with the external environment of the vehicle, also called face F1). In addition, each of the sheets 41, 42 comprises an edge 41_T, 42_T.

[0015] The glazed assembly 30 also comprises a seal 50, for example a finishing seal 50, comprising: - a part 51 called “fixing” maintained in contact, thanks to adhesive means 60 of a type known per se, with the internal main face 41_I, - a so-called “contact” part 52 arranged opposite the edge of the glazing 40 (i.e. opposite the edges 41_T, 42_T of the internal 41, external 42 sheets) and comprising a flat face 53 in contact with the edge 42_T of the external glass sheet 42, - a projection 54 arranged in the extension of the flat face 53 of the contact part 52. In this example, said projection 54 is made so as to be level with the external main face 42_E of the external glass sheet 42.

[0016] As illustrated by [Fig.2], the seal 50, and more particularly the projection 52, does not entirely cover the rounded part of the edge 42_T connected to the external main face 42_E. Indeed, despite the fact that it may have a certain elasticity, the contact part 52, via its flat face 53, cannot fit in its entirety the edge 42_T given the rounded shape of the latter. This results (as shown in bold line in [Fig.2]) in a part 42_T_N of the edge 42_T left bare.

[0017] The presence of this bare part 42_T_N is problematic. Indeed, and according to a first aspect, it causes a visual defect in the glazing when it is observed from the outside.

[0018] But also, this bare part 42_T_N creates, at the junction with the projection 54, an area capable of receiving foreign bodies (example: dust, gravel, etc.) likely to damage the glazing.

[0019] Finally, yet another problematic aspect linked to the presence of this bare part 42_T_N is the fact that the seal 50 is not able to create a hold for the external sheet 42 at the level of its entire edge 42_T. The impact resistance of the glazing, at the level of the junction with the projection 54 is therefore affected.

[0020] It should be noted that these different issues, although mentioned until now only in connection with the automotive sector, also apply in other fields, such as the construction sector.

[0021] Statement of the invention

[0022] The present invention aims to overcome all or part of the drawbacks of the prior art, in particular those set out above, by proposing a solution which makes it possible to obtain a machined glass sheet so that the edge does not have a bare part when it cooperates with an already existing finishing and / or sealing joint (i.e. a prefabricated finishing and / or sealing joint identical to those used in the state of the art).

[0023] This solution therefore offers the possibility of producing a glazed assembly (glazing fitted with a seal) which does not present any visual defects when observed from the outside, and which is also very robust (absence of damage due to the presence of foreign bodies, good impact resistance) in comparison with the solutions of the state of the art.

[0024] To this end, and according to a first aspect, the invention relates to a glass sheet comprising two main faces, a first main face and a second main face, opposite and separated by an edge. In addition, the edge comprises, on at least part of the periphery of the glass sheet: - a first convex curved part connected to the first main face, - a second convex curved part connected to the second main face, - a flat part connecting said first and second curved parts together, the intersection between the flat part and a curved part being constituted, in a cross-section of the glass sheet, by a single point.

[0025] Thus, the glass sheet according to the invention has an edge whose profile allows the projection of a prefabricated seal to completely cover the curved part of the edge connected to the external face of the glass sheet. Consequently, no part of the edge is left bare when it cooperates with a finishing and / or sealing seal.

[0026] This particularly advantageous result results from the presence of the flat part of the edge of the glass sheet. Indeed, unlike what is done in the state of the art, as illustrated by [Fig. 2], a joint cooperating with the edge of the glass sheet according to the invention is not constrained here to fit a completely rounded edge, but can on the contrary be pressed against the flat part of the edge.

[0027] In other words, having a flat part on the edge, between two convex curved parts, makes it possible to reduce the machining height in comparison with the state-of-the-art achievements, and therefore to have an edge extending (in a cross-section to the glass sheet) over a distance less than that resulting from a fully curved edge profile. This gain in distance is beneficial for the plating of the joint, the projection of which can then come to completely cover the curved part of the edge connected to the external face of the glass sheet.

[0028] In particular embodiments, the glass sheet may further comprise one or more of the following characteristics, taken individually or in any technically possible combination.

[0029] In particular embodiments, the first and second curved portions are circular arcs, for example circular arcs of identical respective radii and identical respective lengths.

[0030] In particular embodiments, the first and second curved portions are circular arcs of identical respective radii and identical respective lengths, the planar portion being orthogonal to the main faces.

[0031] In particular embodiments, the angle, called “machining opening”, defining the gap between: - a first straight line tangential to the first curved part at the point of connection between said first curved part and the first main face, - a second straight line tangential to the second curved part at the point of connection between said second curved part and the second main face, is between 20° and 120°, more particularly between 20° and 80°, preferably between 20° and 50°, for example equal to 36°.

[0032] In particular embodiments, the first, second curved parts as well as the flat part are produced around the entire periphery of the glass sheet.

[0033] According to a second aspect, the invention relates to a method of machining a glass sheet, said method comprising steps of: - obtaining a sheet of glass with a flat edge, - inserting the glass sheet, by the edge, into a groove of a rotating grinding wheel, said groove being provided with an abrasive surface, said insertion being carried out until reaching the bottom of the groove which is shaped so that once the bottom is reached, the glass sheet is in accordance with the invention, - removal of the glass sheet from the groove.

[0034] According to a third aspect, the invention relates to a monolithic glazing comprising a glass sheet according to the invention.

[0035] According to a fourth aspect, the invention relates to a laminated glazing comprising two sheets of glass, an inner sheet and an outer sheet, separated by an interlayer film, at least said outer sheet being in accordance with the invention.

[0036] In particular embodiments, the laminated glazing may further comprise one or more of the following characteristics, taken individually or in all technically possible combinations.

[0037] In particular embodiments, the inner sheet is also in accordance with the invention.

[0038] In particular embodiments, the inner and outer sheets are arranged so that, in a cross-section of the glazing, the respective flat parts of said inner and outer sheets are aligned with the edge of the interlayer film.

[0039] According to a fifth aspect, the invention relates to a glazed assembly comprising a glazing according to the invention as well as a finishing and / or sealing joint comprising: - a so-called "contact" part arranged opposite the edge of the glazing and comprising a flat face in contact with the flat part of the edge belonging to the glass sheet, a main face called "external" of which is intended to provide the interface with an external environment, - a projection arranged in the extension of the flat face of the contact part, said projection being configured to cover the entire curved part connected to said main external face.

[0040] According to a sixth aspect, the invention relates to a use of a glazed assembly according to the invention in a motor vehicle, for example as a windshield, rear window, side window or glazed roof, or in a building.

[0041] According to a seventh aspect, the invention relates to a motor vehicle comprising a glazed assembly according to the invention.

[0042] Brief description of the drawings

[0043] Other characteristics and advantages of the present invention will emerge from the description given below, with reference to the appended drawings which illustrate an exemplary embodiment thereof without any limiting character. In the figures:

[0044] [Fig-1] [Fig.l] schematically represents an example of the production of a grinding wheel allowing the edge of a sheet of glass to be machined as is known in the state of the art;

[0045] [Fig.2] [Fig.2] schematically represents a glazed assembly according to the state of the technique, comprising laminated glazing whose glass sheets have been machined using the grinding wheel of [Fig.l];

[0046] [Fig.3] [Fig.3] schematically represents a particular embodiment of a grinding wheel for machining the edge of a glass sheet, so as to obtain a glass sheet machined according to the invention;

[0047] [Fig.4] [Fig.4] schematically represents the glass sheet obtained after machining using the grinding wheel of [Fig.3];

[0048] [Fig.5] [Fig.5] represents, in the form of a flowchart, the main stages of a machining method according to the invention making it possible to obtain the glass sheet of [Fig.4];

[0049] [Fig.6] [Fig.6] schematically represents a particular embodiment of a glazed assembly according to the invention, said glazed assembly comprising laminated glazing whose external glass sheet conforms to [Fig.3];

[0050] [Fig.7] [Fig.7] schematically represents a particular embodiment of a glazed assembly according to the invention, said glazed assembly comprising monolithic glazing whose glass sheet conforms to [Fig.3].

[0051]

[0052] Description of embodiments

[0053] [Fig. 3] schematically represents a particular embodiment of a grinding wheel 200 making it possible to machine the edge 130 of a glass sheet 100, so as to obtain a machined glass sheet 100 according to the invention.

[0054] [Fig. 3] corresponds more particularly to a close-up partial view along a cross-section of the glass sheet 100, before the latter is machined.

[0055] For the remainder of the description, it is considered in a non-limiting manner that the glass sheet 100 is intended to be used, after machining, to form a windshield of a motor vehicle which may indifferently be a car, a bus, a truck, etc.

[0056] It should however be noted that considering a glass sheet to form a windshield of a motor vehicle constitutes only a variant implementation of the invention. Also, nothing excludes using a glass sheet according to the invention for another type of automotive glazing, such as for example a rear window, a side window or even a glass roof.

[0057] More generally, the use of a glass sheet according to the invention is not limited to the automotive field, but can also be applied to the building field, for example to equip a window or a glass facade.

[0058] For the remainder of the description, it is also considered in a non-limiting manner that the machining of the glass sheet 100 is carried out over the entire periphery of the glass sheet 100. Such arrangements are in no way limiting of the invention, and nothing excludes envisaging machining over only a portion of the periphery of the glass sheet 100. The choice of machining over all or part of the periphery of the glass sheet 100 is typically made according to the intended use for the sheet 100 once machined.

[0059] As illustrated by [Fig. 3], the glass sheet 100 comprises two main faces, a first main face 110 (for example intended to be oriented towards an external environment) and a second main face 120 (for example intended to be oriented towards an internal environment). The two main faces 110, 120 are opposite, parallel and separated by the edge 130. It should be noted that before machining, the edge 130 is flat and orthogonal to the main faces 110, 120 (the glass sheet 100 resulting for example from a cutting operation in a larger glass plate).

[0060] In the embodiment of [Fig. 3], the glass sheet 100 is shown in its initial machining configuration, that is to say at the start of its insertion, by the edge 130, into a groove 210 of the grinding wheel 200 (only a part of the grinding wheel 200 is shown here due to the close-up partial view).

[0061] The groove 210 has a geometric configuration intended to be imparted to the edge 130 of the sheet 100 following machining. By "intended to be imparted", it is to be understood that once the glass sheet 100 is inserted to the bottom of the groove 210, then removed, the edge 130 has a shape identical to that of the groove 210. Consequently, describing the shape of the groove 210 is equivalent to describing the shape of the edge 130 after machining, taking into account the fact that a shape considered to be concave on a portion of the groove 210 (i.e. a shape re-entering towards the inside of the grinding wheel 200) will become a corresponding convex shape on a portion of the edge 130 (i.e. a shape protruding towards the outside of the glass sheet 100).

[0062] To give the slice 130 a shape in accordance with the invention, the groove 210 has a generally concave shape, and its surface is provided with diamond particles (not shown in [Fig. 3]) suitable for machining the glass sheet 100.

[0063] More particularly, the geometric shape of the surface of the groove 210 comprises: - a first concave curved part 211, in contact with the junction edge between the edge 130 and the first main face 110 of the glass sheet 100 when the latter is in the initial machining configuration, - a second convex curved portion 212 in contact with the junction edge between the edge 130 and the second main face 120 of the glass sheet 100 when the latter is in the initial machining configuration.

[0064] The geometric shape of the groove 210 further comprises a flat part 213 connecting said first and second curved parts 211, 212 together, this connection being made between the ends of the first and second curved parts 211, 212 which are not in contact with the edge 130 when the glass sheet 100 is in its initial machining configuration.

[0065] This flat part 213 is notably characterized by the fact that its intersection with the curved part 211 (respectively its intersection with the curved part 212) is constituted, in a cross-section of the glass sheet 100, by a single point. These arrangements therefore imply that the flat part 213 cannot form, in said cross-section of [Fig. 3], a segment subtending all or part of the curved part 211 (respectively all or part of the curved part 212). In this way, the slice 130 will acquire, due to the machining, a flat part forming the end of the glass sheet 100 and therefore configured to be in contact with a joint (finishing and / or sealing) as detailed later.

[0066] It should be noted that by “curved part”, reference is made in the sense of the present invention to a curved part making a connection between the flat part 213 and a main face 110, 120.

[0067] In the embodiment of [Fig. 3], the first and second curved portions 211, 212 are more particularly circular arcs. These circular arcs 211, 212 have identical respective radii (i.e. the lengths of these radii are equal) and have identical respective lengths. The centers of the circular arcs are indicated by the references C_211, C_212 in [Fig. 3].

[0068] Considering curved portions 211, 212 in the form of circular arcs constitutes only a variant implementation of the invention. Thus, nothing excludes considering other embodiments in which at least one curved portion has a shape other than a circular arc, such as for example elliptical, parabolic, etc.

[0069] Furthermore, in the embodiment of [Fig. 3], the glass sheet 100 is positioned, in its initial machining configuration, so that the edge 130 is parallel to the flat part 213. In this way, after machining, the edge 130 also has a flat part, the latter being more particularly orthogonal to the main faces 110, 120.

[0070] The machining height H_210 is also shown in [Fig.3], and therefore corresponds, in this embodiment, to the distance separating the edge 130 (when the glass sheet 100 is arranged in its initial machining configuration) and the flat part 213.

[0071] In a similar manner to what has been described previously with reference to [Fig.l], and as illustrated by [Fig.3], the groove 210 is connected to edges 220, 230 of the grinding wheel 200 (these edges 220, 230 forming part of the periphery of the grinding wheel 200) by rounded surfaces 240, 250. These rounded surfaces correspond, in the embodiment described here, to arcs of a circle whose respective centers are indicated by the references C_240, C_250 and whose respective radii are equal.

[0072] The geometric configuration of the groove 210 (position of the centers C_211, C_212, values ​​of the radii of the associated circular arcs, machining height H_210) makes it possible to define an angle, called “machining opening”, characterizing the way in which the glass sheet 100 is machined by means of the grinding wheel 200. More particularly, this machining opening defines the gap, when the glass sheet 100 is in the initial machining configuration, between two straight lines (represented in dotted lines in [Fig. 3]): - a first straight line DI (represented in dotted lines) tangential to the first curved part 211 at the point of contact (referenced P_211 in [Fig. 3]) between said first curved part 211 and the edge 130, - a second straight line D2 (represented in dotted lines) tangential to the second curved part 212 at the connection point (referenced P_212 in [Fig.3]) between said second curved part 212 and the edge 130.

[0073] Said machining opening is for example between 20° and 120°, more particularly between 20° and 80°, preferably between 20° and 50°. The inventors have notably noted that reducing the machining opening (which also amounts to increasing the length of the radii defining the arcs of circles of the curved parts 211, 212) makes it possible to reduce the risk of flaking appearing at the edge of the wafer 130 during machining. In particular, a machining opening of less than 50° makes it possible to greatly reduce this risk.

[0074] It is clear from the above description that the geometry of the edge 130 after machining ultimately depends on all or part of the following parameters: - the shape of each of the curved parts 211, 212 (example: arc of a circle), - the geometric characteristics of said curved parts (example: radius and length in the case of an arc of a circle), - the value of the machining height, - the position of the glass sheet 100 in its initial machining configuration (example: perpendicular or inclined relative to the edge of the grinding wheel 200), - the value of the machining opening.

[0075] An appropriate choice of one or more of these parameters thus makes it possible to guarantee, according to an example conforming to that of [Fig.3], that the slice 130 is orthogonal to the main faces 110, 120.

[0076] However, nothing precludes considering embodiments in which, after machining, the edge 130 of the glass sheet 100 is inclined relative to the main faces 110, 120. Such an inclination can be obtained by modifying any one or more of the parameters mentioned above.

[0077] By way of non-limiting example, the value of one (or more) radius(es) of an arc of a circle of one (or more) curved part(s) is substantially or exactly equal to one third of the thickness of the glass sheet 100.

[0078] The machining height, for its part, is for example between 1 / 3 and 1 / 5 of the thickness of the glass sheet 100, for example substantially or exactly equal to 1 / 4 of the thickness of the glass sheet 100.

[0079] [Fig.4] schematically represents the glass sheet 100 obtained after machining using the grinding wheel 200 of [Fig.3].

[0080] As illustrated by [Fig.4], the edge 130 of the glass sheet 100 has, after machining, a profile corresponding to that of the groove 210 of the grinding wheel 200.

[0081] In this respect, section 130 includes: - a first convex curved part 131 connected to the first main face 110. This first curved part 131 has a shape corresponding to that of the first curved part 211 of the groove 210. The connection point between this first curved part 131 and the first main face 110 is referenced P_131 in [Fig.4], and is the same as the point P_211 when the glass sheet 100 is inserted at the bottom of the groove 210, - a second convex curved part 132 connected to the second main face 120. This second curved part 132 has a shape corresponding to that of the second curved part 212 of the groove 210. The connection point between this second curved part 132 and the second main face 120 is referenced P_132 in [Fig.4], and is the same as the point P_212 when the glass sheet 100 is inserted at the bottom of the groove 210, - a flat part 133 connecting said first and second curved parts 131, 132 together. This flat part 133 has a shape corresponding to that of the flat part 213 of the groove 210. For this purpose, the intersection between the flat part 133 and a curved part 131, 132 is constituted, in a cross-section of the glass sheet 100, by a single point.

[0082] The machining opening defined above in connection with the groove 210 of the grinding wheel 200 of course has an equivalent with regard to the glass sheet 100. For this purpose, with regard to the glass sheet 100 and as illustrated by [Fig. 4], said machining opening corresponds to the angle defining the gap between two straight lines (represented in dotted lines in [Fig. 4]): - a first straight line DI tangential to the first curved part 131 at the connection point P_131, - a second straight line D2 tangential to the second curved part 132 at the connection point P_132.

[0083] It should be noted that in this example of [Fig.4], it is equivalent to define the machining opening as the angular difference between the straight lines DI and D2, or as the angular difference between the straight line DI (respectively the straight line D2) and the first main face 110 (respectively the second main face 120). Indeed, due to the fact of the symmetry of the machined glass sheet with respect to the mediator at the flat part 133, the angular deviations between these lines D1, D2 and their associated main faces are equal. The invention is nevertheless not limited by such provisions, and, as already mentioned, the modification of one or more of the parameters listed above makes it possible to envisage embodiments in which the angular deviation between the line D1 and the face 110 differs from the angular deviation between the line D2 and the face 120.

[0084] Several examples of the production of glass sheets according to the invention are now described: - example ri 1: the thickness of the glass sheet is equal to 1.1 mm, the machining height is equal to 0.24 mm, the machining opening is equal to 36°, the first and second curved parts of the edge are circular arcs of the same radius equal to 0.35 mm and of the same length, the center of a circular arc is located on the straight line orthogonal to the flat part of the edge and passing through the junction point between said flat part and said circular arc; - example no. 2: the thickness of the glass sheet is equal to 1.6 mm, the machining height is equal to 0.38 mm, the machining opening is equal to 36°, the first and second curved parts of the edge are circular arcs of the same radius equal to 0.55 mm and of the same length, the center of a circular arc is located on the straight line orthogonal to the flat part of the edge and passing through the junction point between said flat part and said circular arc; - example no. 3: the thickness of the glass sheet is equal to 1.8 mm, the machining height is equal to 0.41 mm, the machining opening is equal to 36°, the first and second curved parts of the edge are circular arcs of the same radius equal to 0.6 mm and of the same length, the center of a circular arc is located on the straight line orthogonal to the flat part of the edge and passing through the junction point between said flat part and said circular arc; - example no. 4: the thickness of the glass sheet is equal to 2.1 mm, the machining height is equal to 0.48 mm, the machining opening is equal to 36°, the first and second curved parts of the edge are circular arcs of the same radius equal to 0.7 mm and of the same length, the center of a circular arc is located on the straight line orthogonal to the flat part of the edge and passing through the junction point between said flat part and said circular arc; - example no. 5: the thickness of the glass sheet is equal to 2.6 mm, the machining height is equal to 0.59 mm, the machining opening is equal to 36°, the first and second curved parts of the edge are circular arcs of the same radius equal to 0.85 mm and of the same length, the center of a circular arc is located on the straight line orthogonal to the flat part of the edge and passing through the junction point between said flat part and said circular arc.

[0085] Of course, these examples No. 1-5 are given purely for illustrative purposes. In particular, no limitation is attached to the numerical values ​​relating to the thickness of the glass, the machining height, the radius of an arc of a circle, the machining opening, since the slice 130 has a profile in accordance with the invention.

[0086] It may also be noted that in these examples No. 1-5, the value of a radius of a circle arc is substantially or exactly equal to one third of the thickness of the glass. However, here again, such arrangements are not limiting of the invention.

[0087] According to another aspect, the invention also relates to a method for machining a glass sheet. [Fig. 5] represents, in the form of a flowchart, the main steps of said machining method making it possible to obtain the glass sheet 100 of [Fig. 4].

[0088] As illustrated by [Fig.5], the method firstly comprises a step E10 of obtaining the glass sheet 100 whose edge is flat (i.e. the edge is entirely flat before machining).

[0089] In a particular embodiment, obtaining the glass sheet 100 refers solely to providing it, after it has been cut from a glass plate for example.

[0090] In another particular embodiment, the obtaining step E10 comprises cutting a glass plate, so as to form said glass sheet 100 with a flat edge.

[0091] Said glass sheet 100 is then inserted, by the edge 130, into the groove 210 of the rotating grinding wheel 200. This insertion is the subject of a step E20 of the machining method, and is carried out until the edge 130 of the glass sheet 100 reaches the bottom of the groove 210.

[0092] Once the insertion is complete (i.e. once the edge 130 of the glass sheet 100 has reached the bottom of the groove 210), the method comprises a final step E30 of removing the glass sheet 100, the edge 130 of which is now machined in accordance with the shape of the groove 210.

[0093] In addition to a machined glass sheet and a machining method as described above, the invention also covers other aspects, namely a glazing comprising such a machined glass sheet as well as a glazed assembly comprising said glazing.

[0094] [Fig.6] schematically represents a particular embodiment of a glazed assembly ENS_V according to the invention.

[0095] In the embodiment of [Fig.6], said glazed assembly ENS_V comprises a laminated glazing unit 300 for a motor vehicle. Said laminated glazing unit 300 comprises two sheets of glass, an inner sheet 310 and an outer sheet 320, separated by an interlayer film 330.

[0096] The internal glass sheet 310 (respectively the external glass sheet 320) is intended to be arranged on the inside of the vehicle, i.e. in contact with the passenger compartment of the vehicle (respectively to be arranged on the outside of the vehicle, i.e. in direct contact with the environment external to the vehicle).

[0097] Each glass sheet 310, 320 comprises a first main face 311, 321, called “external”, intended to be oriented towards the outside of the vehicle, as well as a second opposite main face 312, 322, called “internal”. The internal and external faces of a sheet are connected to each other by a peripheral edge 313, 323. Conventionally, the internal and external faces 321, 322 of the external sheet 320 (respectively the internal and external faces 311, 312 of the internal sheet 310) are also respectively called face F1 and face F2 (respectively face F3 and face F4).

[0098] No limitation is attached to the nature of the glass used to form the glass sheets 310, 320. Thus, it may be organic or mineral glass. The glass sheets 310, 320 may also be made of non-tempered, partially tempered or tempered glass.

[0099] For example, the outer glass sheet 320 and / or inner glass sheet 310 is made of soda-lime glass, quartz glass, borosilicate glass or aluminosilicate glass. According to other examples, the outer glass sheet 320 and / or inner glass sheet 310 is made from rigid and transparent plastic materials, for example polycarbonate, polyethylene terephthalate (PET) or polymethyl methacrylate.

[0100] Preferably, a colorless soda-lime mineral glass such as Planilux® glass marketed by the Applicant will be used for the inner sheet 310. The inner sheet 310 typically has a thickness of between 1.4 and 3.2 mm, preferably between 1.4 and 2.1 mm (this thickness can vary between 2.5 and 6 mm when it is a single glazing, i.e. monolithic and non-laminated).

[0101] The outer sheet 320 can of course be as transparent and colorless as the inner sheet 310. In exemplary embodiments, a laminated glazing according to the invention will consist of two colorless Planilux® sheets.

[0102] Unlike the inner sheet 310, the outer sheet 320 is advantageously made of tinted glass, for example Venus®, TSA3+ or TSA4+ glass also marketed by the Applicant. The outer sheet 320 typically has a thickness of between 1.4 and 2.1 mm.

[0103] In more specific embodiments (not illustrated in the figures), said laminated glazing may comprise a functional layer. No limitation is attached to the nature of said functional layer. For example, it may be a layer reflecting infrared radiation. Generally speaking, a person skilled in the art knows which functional layers can be envisaged for a laminated glazing of a motor vehicle, and also knows where to position (i.e. on which face of the glazing) such a functional layer. Therefore, these aspects are not described further here.

[0104] The interlayer film 330, for its part, is in adhesive contact with the two glass sheets 310, 320, and more precisely with the first main face 321 of the external sheet 320 and the second main face 312 of the internal sheet 310. It can be made of any transparent polymer material commonly used for this purpose, for example polyvinyl butyral (PVB), thermoplastic polyurethane (TPU) or ethylene and vinyl acetate copolymer (EVA). It typically has a thickness of between 0.2 and 1.1 mm, and can be colorless or tinted in sections or entirely.

[0105] The glazing 300 is also characterized by the fact that the outer sheet 320 is machined in accordance with the invention. More particularly, in the embodiment described here, the outer sheet 320 has an edge 323 whose profile is identical to that described above for the glass sheet of [Fig.4].

[0106] It should be noted that the internal glass sheet 310 is, from the point of view of the shape of its edge 313, in accordance with the state of the art. More particularly, in the embodiment described here, the internal sheet 310 has an edge 313 whose profile is identical to that described above for the internal / external sheet of [Fig.2].

[0107] However, considering a glazing 300 in which only the outer sheet 320 has an edge 323 comprising curved parts as well as a flat part only constitutes a variant implementation of the invention. Thus, nothing precludes considering other embodiments in which the outer glass sheet and the inner glass sheet of a laminated glazing are both machined in accordance with the invention.

[0108] Even more specifically, when said internal and external sheets are machined in accordance with the invention, it may be envisaged that they are arranged so that, in a cross-section of the glazing, the respective flat parts of said internal and external sheets are aligned with the edge of the interlayer film.

[0109] In addition to the glazing 300, the glazed assembly ENS_V also comprises a finishing seal meeting technical characteristics identical to those described for the finishing seal 50 of [Fig.l], the numerical references of which are reproduced here. It should however be noted that the fact of using a seal having only finishing properties is not limiting of the invention, and nothing of course excludes considering a seal having only sealing properties or even both finishing and sealing properties.

[0110] Thus, in the embodiment of [Fig.6], the finishing joint 50 comprises: - a part 51 called “fixing” held in contact, thanks to adhesive means 60 of a type known per se, with the internal face 312 of the internal sheet 310, - a so-called “contact” part 52 arranged opposite the edge of the glazing 300 (i.e. opposite the edges 313, 323 of the internal and external sheets 310, 320) and comprising a flat face 53 in contact with the edge 323 of the external glass sheet 320, - a projection 54 arranged in the extension of the flat face 53 of the contact part 52. In this example, said projection 54 is made so as to be level with the external face 321 of the external glass sheet 320.

[0111] The fixing part 51 is for example made of a harder material than that of the contact part 52. The seal 50 nevertheless forms, in the embodiment described here and without limitation, a single and same part obtained in a manner known per se, typically by extrusion.

[0112] As illustrated by [Fig. 6], the seal 50, and more particularly the projection 54, completely covers the curved part of the edge 323 connected to the outer main face 321 of the outer sheet 320. Consequently, no part of the edge 323 of the outer sheet 320 is left bare. This result results from the presence of the flat part of the edge 323 of the outer glass sheet 320. Indeed, unlike the configuration illustrated by [Fig. 2], the seal 50 is not forced here to fit a completely rounded edge, but can on the contrary be pressed against the flat part of the edge 323.

[0113] It should be noted that the fact of considering a fixing of the seal 50 to the glazing 300 via the fixing part 51 and the adhesive means 60 constitutes only a variant implementation of the invention. Also, and in general, any method known to those skilled in the art for fixing a seal comprising at least one contact part 52 and a projection 54 can be envisaged.

[0114] Furthermore, the glazed assembly ENS_V has been described up to now considering that the glazing 300 equipping the latter is a laminated glazing. Of course, these provisions are not limiting of the invention which also covers the case of a glazed assembly equipped with a monolithic glazing. Such a configuration is illustrated in a non-limiting manner by [Fig.7] in which the numerical references of [Fig.6] have been used for the corresponding elements.

Claims

Claims

1. Glass sheet (100) comprising two main faces, a first main face (110) and a second main face (120), opposite each other and separated by an edge (130), said sheet being characterized in that the edge comprises, on at least part of the periphery of the glass sheet: - a first convex curved part (131) connected to the first main face, - a second convex curved part (132) connected to the second main face, - a flat part (133) connecting said first and second curved parts together, the intersection between the flat part and a curved part being constituted, in a cross-section of the glass sheet, by a single point in which the first and second curved parts (131, 132) are circular arcs of identical respective radii and identical respective lengths, the flat part (133) being orthogonal to the main faces (110, 120), and in which the angle,called "machining opening", defining the gap between: - a first straight line (Dl) tangential to the first curved part (131) at the connection point (P_131) between said first curved part and the first main face (110), - a second straight line (D2) tangential to the second curved part (132) at the connection point (P_132) between said second curved part and the second main face (120), is between 20° and 120°, more particularly between 20° and 80°, preferably between 20° and 50°, for example equal to 36°.,

2. Glass sheet (100) according to claim 1, wherein the first, second curved portions (131, 132) as well as the flat portion (133) are produced around the entire periphery of the glass sheet.

3. Method for machining a glass sheet (100), said method comprising steps of: - obtaining (E10) a glass sheet whose edge is flat, - inserting (E20) the glass sheet, by the edge, into a groove of a rotating grinding wheel, said groove being provided with an abrasive surface, said insertion being carried out until reaching the bottom of the groove which is shaped so that once the bottom is reached, the glass sheet conforms to any one of claims 1 to 2, - removal (E30) of the glass sheet from the groove.

4. Monolithic glazing comprising a glass sheet according to any one of claims 1 to 2.

5. Laminated glazing (300) comprising two sheets of glass, an inner sheet (310) and an outer sheet (320), separated by an interlayer film (330), at least said outer sheet being in accordance with any one of claims 1 to 2.

6. Laminated glazing (300) according to claim 8, wherein the inner sheet (310) also conforms to any one of claims 1 to 2.

7. Laminated glazing (300) according to claim 6, wherein the inner and outer sheets (310, 320) are arranged so that, in a cross-section of the glazing, the respective flat portions of said inner and outer sheets are aligned with the edge of the interlayer film (330).

8. Glazed assembly (ENS_V) comprising a glazing (300) according to any one of claims 4 to 7 as well as a finishing and / or sealing joint (50) comprising: - a so-called "contact" part (52) arranged opposite the edge of the glazing and comprising a flat face (53) in contact with the flat part of the edge (323) belonging to the glass sheet (320) of which a main face called "external" (321) is intended to provide the interface with an external environment, - a projection (54) arranged in the extension of the flat face of the contact part, said projection being configured to cover the entire curved part connected to said main external face.

9. Use of a glazed assembly (ENS_V) according to claim 8 in a motor vehicle, for example as a windshield, rear window, side window or glass roof, or in a building.

10. Motor vehicle comprising a glazed assembly (ENS_V) according to claim 8.

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