FR3078918A1 - GLAZING WITH PROGRAMMED BREAKING PROTECTION FILM - Google Patents

Abstract

Glazing (10, 100) having a tempered glass pane (11, 110), and a plastic film (12, 120) adhered to one of the faces of the pane (11, 110), the edges of said plastic film (12) 120) being remote from the edges of the pane (11, 110) so as to leave a plastic film-free web (14, 140) (12, 120) on the surface of the pane (11, 110) around the film plastic (12, 120), characterized in that the plastic film (12, 120) has a breaking initiation zone (15) disposed on one of these edges (12, 120).

Description

GLASS WITH PROTECTIVE FILM WITH PROGRAMMED BREAK

The invention relates to glazing comprising a protective film, as well as to a vehicle comprising such glazing.

Some vehicle windows are made of tempered glass. The advantage of using tempered glass for vehicle glazing is that, when this glazing breaks, it does not make long pointed and sharp pieces but it breaks into small pieces which are not very sharp. This type of glazing, regulatory in the automotive field, is therefore less dangerous than unhardened glazing when it is broken. In order to reinforce such glazing or to protect elements glued to such glazing, it is known to apply a plastic film to the surface of the glazing. For example, patent EP1336520 describes a glass pane comprising a protective film bonded to one of these faces. Photovoltaic cells can be placed on the surface of the glazing, covered by the plastic film in order to protect them. The glazing is fixed to the vehicle by a bead of glue placed on its periphery, directly in contact with the glass, because the bead of glue does not adhere well to the plastic film. The plastic film extends over a smaller surface than that of the glazing so as to leave a strip without plastic film all around the glazing on which the bead of adhesive is directly in contact with the glass.

The disadvantage of such a solution is that, when the tempered glass glazing is broken, for example following an impact of an object, it breaks into a large number of small pieces and all the pieces of the part of the glazing on which the plastic film is applied remains integral with the plastic film. All this part of the glazing broken into small pieces which remains integral with the plastic film separates from the part of the glazing glued to the adhesive bead and falls in one piece under its weight, because the plastic film is not fixed to the adhesive bead or to the part of the glazing glued to the adhesive bead. When such glazing forms a rear window or part of the roof of the vehicle, the fall of the part of the glazing integral with the plastic film may injure the passengers located below, in the vehicle, because of its size and its mass. .

The objective of the invention is to remedy these drawbacks. In particular, one of the aims of the invention is to provide glazing with a protective film which improves passenger safety.

This object is achieved according to the invention, thanks to a glazing comprising a tempered glass pane, and a plastic film bonded to one of the faces of the pane, the edges of said plastic film being at a distance from the edges of the pane so to leave a free strip of plastic film on the surface of the glass around the plastic film, remarkable in that the plastic film comprises a zone of initiation of rupture disposed on one of these edges.

Advantageously, if the tempered glass pane is broken and explodes into a large number of small pieces following an impact, these numerous small pieces remain stuck to the plastic film which, under the weight of these small pieces of glass, is cut from from the low resistance area. When cut, the plastic film with the small pieces of glass stuck on it forms several broken glazing plates, which come off, smaller than the size of the entire plastic film. These glazing plates are therefore lighter than a plate which would be formed by detaching the entire plastic film with pieces of glass glued to it. The risk of injuring passengers under or near the window is greatly reduced.

In a preferred embodiment of the invention, the rupture initiation zone is a notch disposed on one of the edges of the plastic film.

Advantageously, the zone of low resistance is produced in a simple manner by the shape of the cutout of the edge of the plastic film. The notch allows mechanical stresses to be concentrated in a particular area, and thus facilitates the initiation of film cutting under the weight of small pieces of glass.

In one embodiment of the invention, the notch has a triangular shape, two sides of which extend towards the inside of the plastic film.

Thus, advantageously, the stress concentration is particularly high in a very small area formed by the apex of the triangle located the innermost of the film and forming the bottom of the notch, the side of the triangle opposite this apex being in the alignment of the edge of the plastic film. The initiation of the cutting of the plastic film under the weight of the pieces of glass in the event of breakage of the glass is therefore very quickly initiated starting from this vertex of the triangle located in the bottom of the notch.

In another embodiment of the invention, the angle of the apex of the notch formed by the two sides of the triangle which extend towards the inside of the plastic film has an angle of less than sixty degrees, preferably less than thirty degrees.

Thus advantageously, the concentration of the stresses at the level of the top of the notch is particularly important, and therefore the tearing of the plastic film is quickly initiated under the weight of the pieces of glass when said glass is broken.

Preferably, the plastic film has notches on two of its edges, one facing the other, so as to favor cutting of the plastic film between these two notches.

In another embodiment of the invention, the plastic film comprises a weakened line along which the thickness of the plastic film is less than in the rest of said plastic film, said line extending from one of the edges of the plastic film at another of its edges from a rupture initiation zone to another rupture initiation zone.

Advantageously, the plastic film is cut under the effect of the weight of small pieces of glass when the glass is broken, following the weakened line, the end of the line at the edge of the pastic film forming a primer area breaking thanks to the reduced thickness of said plastic film along this line which weakens the plastic film. It is thus possible to define the form in which the film will be cut.

In another embodiment of the invention, the thickness of the plastic film along the weakened line is less than 50% of the thickness of the plastic film outside this weakened line, preferably less than 30% of the thickness of the plastic film outside this weakened line.

These thicknesses ensure quick and precise cutting when the glass is broken. Preferably, the plastic film has several weakened lines.

In another embodiment of the invention, the thickness of the plastic film in the weakened line is reduced as it approaches the edge of the plastic film. This reduction in thickness favors the cutting of the plastic film from the end of the line.

Thus, advantageously, the weakened line incorporates a more fragile area at the edge of the plastic film at which the cutting of said plastic film begins in the event of breakage of the window. The end of the weakened line thus forms a zone of initiation of rupture which is more fragile than the rest of the line, thus ensuring a cutting of the weakened line from its ends.

In another embodiment of the invention, each end of the weakened line opens at the bottom of one of the notches.

Thus advantageously, the cutting of the plastic film under the weight of the pieces of glass is favored by the combination of the rupture initiation zone and the weakened line, and this cutting is done by following a shape given by the weakened line.

The invention also relates to a vehicle comprising glazing as described above, preferably the plastic film being bonded to the face of the window oriented towards the side of the interior of the vehicle.

In another embodiment of the invention relating to the vehicle, the glazing is a rear window glazing or a roof glazing of the vehicle.

The invention will be better understood on reading the description which follows, given solely by way of example and made with reference to the appended drawings, in which:

Figure 1 is a perspective view of three rear quarter of a vehicle having two panes according to the invention, one of the panes forming a rear window and the other a roof window.

Figure 2 is a view of a first embodiment of the glazing.

FIG. 3 is a sectional view A-A of the glazing of FIG. 2.

Figure 4 is a view of a second embodiment of the glazing.

FIG. 5 is a sectional view B-B of the glazing of FIG. 4.

The drawings are schematic representations to facilitate understanding of the invention. The components are not necessarily shown to scale. The same references correspond to the same components from one figure to another.

FIG. 1 illustrates a vehicle 1 comprising a first glazing 10 according to the invention forming a rear window and a second glazing 100 according to the invention forming a glazed roof.

The first window 10 comprises a first window 11 of toughened glass and a first plastic film 12 bonded to the surface of said first window 11, on the face of this first window 11 oriented towards the side of the passenger compartment of the vehicle 1. The second window 100 comprises a second window 110 of tempered glass and a second plastic film 120 bonded to the surface of said second window 110, on the face of this second window 110 oriented towards the side of the passenger compartment of the vehicle 1. The first glazing 10 comprises in addition to a network of heating wires 13 for defrosting / demisting on the face of the glass 11 on which the first plastic film is bonded. The first plastic film 12 is bonded over the heating wires

13. The heating wires 13 are therefore between the glass 11 and the plastic film 12. In this arrangement, the first plastic film 12 protects the heating wires from a risk of degradation by contact with an object ripant on the surface of said first glazing 10 It also makes it possible to protect against the risk of electric shock, in particular when the heating wires 13 are supplied with high electrical voltages such as for example 48 Volts. In addition, on the two panes 10 and 100, the plastic films 12 and 120 make it possible to prevent, when the toughened panes 11 and 110 explode into a large number of small pieces, for example during an impact, these small pieces do not detach from each other. In fact, in the event of an impact against the glazing 10 and 100, the tempered glass panes 11 and 110 break into a large number of small pieces, which all remain stuck to the plastic film 12 and 120.

The following description describes the first window 10 forming the rear window. The first plastic film 12 does not extend over the entire surface of the first window 11 on which it is bonded, but it is of smaller dimensions so as to leave a strip 14 on the surface and all around the first window 11 which either not covered by said first plastic film

12. In other words, the surface of the first window 11 is covered with the first plastic film 12 over its major central part and retains an area, preferably of small width compared to the dimension of the window 11, over the entire periphery of said window 11, forming the strip 14 on which there is no plastic film. On this strip, the glass of the first window 11 is exposed. This strip 14 around the first window 11 allows to leave an area for depositing a bead of adhesive 16 directly on the surface of the first window 11 so that the bead of adhesive 16 is directly in contact with the toughened glass, as illustrated in Figures 3 and 5, and thus ensure good adhesion of the adhesive on the first window 11. This bead of adhesive 16 allows the first glazing 10 to be bonded to structural elements 17 of the vehicle 1. If the bead of adhesive 16 was applied against the plastic film 12, the adhesion would be less good and the glazing 10 would be less well maintained. As a variant, the glazing 11 comprises an area with a bare screen printing in this strip 14, and the adhesive bead 16 is applied at least in part to this screen printing.

The first plastic film 12 has locally on its edges zones of initiation of rupture 15, as illustrated in FIGS. 2, 3 and 4. These zones of initiation of rupture 15 are zones of low resistance arranged on the edges of said first plastic film 12. The first window 11 is of substantially rectangular shape. The first plastic film 12 is also of substantially rectangular shape. The rupture initiation zones 15 are arranged opposite one another on opposite edges of the first plastic film

12. In the event of an impact against the first window 10, the first window 11 breaks into a large number of small pieces which all remain stuck to the first plastic film 12. Under the weight of all these small pieces stuck to the first plastic film 12 , said first plastic film 12 tears starting from the rupture initiation zones 15. Thus, the first broken glazing 10 does not fall in one piece formed by the assembly of the first plastic film 12 on which the pieces of glass of the first window 11, but in small plates following the tearing of the first plastic film 12. These small plates being smaller in area than the surface of the assembly of the first plastic film 12, their weight is lower.

FIGS. 2 and 3 illustrate a first embodiment of the rupture initiation zones 15 in which the said rupture initiation zones 15 are produced by reducing the thickness of the first plastic film 12, locally on the edges of the said first plastic film 12, the thickness reducing as it approaches said edges in the manner of a bevel as illustrated in FIG. 3. As illustrated in FIG. 2, the zones of initiation of rupture 15 extend over a triangular surface with the surface of the first plastic film 12, one of the edges of each triangle corresponding to the edge of said plastic film 12. Other shapes of the rupture initiation zones 15 can be applied, such as for example a rectangular shape extending perpendicularly from the edge of the first plastic film 12.

FIG. 4 illustrates another embodiment of the rupture initiation zones 15 in which these zones 15 are notches of triangular shape arranged on the edges of the first plastic film 12. In this FIG. 4, the heating wires for demisting / defrosting are not shown to simplify the view. This embodiment applies with or without heating wires 18. In the embodiment presented in FIG. 4, the notches 15 are arranged on opposite edges of the first plastic film 12, one facing the other. As a variant, other positions of the notches can be envisaged. The angle of the triangle at the bottom of the notches 15 is for example less than or equal to 60 °, or even less than or equal to 30 °. This triangle shape makes it possible to concentrate the stresses in the bottom of the notches 15 and to initiate the tearing of the first film 12 when the first window 11 is broken, at the top of the notches 15. In the embodiment presented in FIG. 4 , the first plastic film 12 further comprises weakened lines 18 of smaller thickness, crossing from one edge to the other the first plastic film 12 and connecting two zones of initiation of rupture 15 located on two opposite edges. These weakened lines 18 weaken the resistance of the first plastic film 23 locally, facilitate the tearing of this first plastic film 12 and orient this tear along a precise path drawn by the shape of these weakened lines 18. As a variant, the first plastic film 12 does not comprises only break initiation zones 15, without the lines 18.

In another variant, the first plastic film 12 only comprises weakened lines 18 of smaller thicknesses extending from one edge to the other of said first plastic film 12, and the zones of initiation of rupture 15 are produced by the ends of these thinner lines 18 on the edges of the first plastic film 12. In another variant, the thickness of the first plastic film 12 at the end of these lines 18, in these lines, is reduced as it approaches the edge of the first plastic film 12, in order to further reduce the resistance of said first plastic film 12 at these ends of the lines 18, and thus promote the initiation of rupture at these ends.

The same description applies to the second glazing 100 forming the glazed roof, comprising the second glazing 110 and the second plastic film 120. The second plastic film 100 does not extend to the edge of the second glazing 110 in order to create a second strip 140 without plastic film 120. The glazed roof 100 shown in FIG. 1 does not include a network of de-icing wires. The second plastic film 120 has zones of rupture initiation 15 on some of its edges. As a variant, it comprises weakened lines 18 extending between primer zones 15 situated on different edges. As a variant, the glazed roof 100 also includes a network of defrosting wires similar to that of the rear window 10.

FIG. 1 illustrates a vehicle comprising both a rear window 10 and a glass roof 100. As a variant, the vehicle only comprises a rear window 10 without a glass roof, or conversely only a glass roof 100.

Claims (9)

1 / Glazing (10, 100) comprising a glass (11, 110) made of tempered glass and a plastic film (12, 120) bonded to one of the faces of the glass (11, 110), the edges of said plastic film ( 12, 120) being at a distance from the edges of the glass (11, 110) so as to leave a strip (14, 140) free of plastic film (12, 120) on the surface of the glass (11, 110) around the plastic film (12, 120), characterized in that the plastic film (12, 120) has a rupture initiation zone (15) disposed on one of these edges (12, 120). 2 / Glazing (10, 100) according to claim 1, characterized in that the rupture initiation zone (15) is a notch (15) disposed on one of the edges of the plastic film. 3 / glazing (10, 100) according to claim 2, characterized in that the notch (15) has a triangular shape, two sides of which extend towards the inside of the plastic film (12, 120). 4 / The glazing (10, 100) according to claim 3, characterized in that the angle of the apex of the notch (15) formed by the two sides of the triangle which extend towards the inside of the plastic film (12 , 120) has an angle of less than sixty degrees, preferably less than thirty degrees. 5 / glazing (10, 100) according to claim 1, characterized in that the plastic film has a weakened line (18) along which the thickness of the plastic film (12, 120) is less than in the rest of said plastic film (12, 120), said line (18) extending from one of the edges of the plastic film (12, 120) to another of its edges from a rupture initiation zone (15) to another zone failure initiator (15). 6 / glazing (10, 100) according to claim 5, characterized in that the thickness of the plastic film (12, 120) along the weakened line (18) is less than 50% of the thickness of the plastic film ( 12, 120) outside this weakened line (18), preferably less than 30% of the thickness of the plastic film (12, 120) outside this weakened line (18). 7 / Glazing (10, 100) according to one of claims 5 or 6, characterized in that the thickness of the plastic film (12, 120) in the weakened line (18) is reduced by approaching 5 of the edge of the plastic film (12, 120). 8 / Glazing (10, 100) according to one of claims 2 to 5 taken in combination with one of claims 6 or 7, characterized in that each end of the weakened line (18) opens at the bottom of the one of the notches (15). 9 / vehicle (1) comprising a glazing (10, 100) according to one of claims 1 to 8, preferably the plastic film (12, 120) being glued to the face of the glass (11, 110) oriented from side of the vehicle interior. 15 10 / vehicle (1) according to claim 9, characterized in that the glazing (10, 100) is a rear window glazing (10) or a roof glazing (100) of the vehicle (1).