Screw insert for fastening a glass pane, glass element, vehicle and manufacturing process

Abstract

Screw insert (10) for fastening a glass pane (30) to a rigid support, comprising a screw-in sleeve (13) with an internal thread (11), a fastening structure (12) arranged around the screw-in sleeve (13) having a force distribution section (122) which is trapezoidal and flat in shape, wherein the force distribution section (122) is designed to transmit a force introduced into the screw-in sleeve (13) to a surface of the glass pane (30).

Description

[0001] The invention relates to a screw insert for fastening a glass pane to a rigid support, in particular a body shell of a vehicle, a glass element, in particular for a roof of a (motor) vehicle, which has the screw insert according to the invention, a vehicle, in particular a motor vehicle, which has the glass element according to the invention and a method for producing a glass element for fastening to a rigid support.

[0002] Modern vehicles, especially motor vehicles, are increasingly using large glass roofs, which allow plenty of light into the vehicle and thus create a pleasant interior atmosphere. There are also approaches to incorporating electrical modules, such as solar cells, into vehicle roofs to generate electrical energy via the vehicle roof. For this purpose, it is also logical to use glass panes as supports for the solar modules.

[0003] Fig. Figure 1 schematically shows a vehicle 1, in particular the bodyshell 50 of the vehicle 1, which has a large glass pane 30 as a roof. The glass pane 30 is connected to the bodyshell 50 of the vehicle 1 at the attachment points 40. The term "bodyshell" refers to the vehicle's body shell. According to the prior art, the glass pane 30 is typically screwed to the bodyshell.

[0004] In order to screw the glass pane to the bodyshell, screw inserts are used in vehicle construction. These are bonded to the glass pane, for example, by adhesive bonding or overmolding, and into which a screw can then be inserted for fastening to the bodyshell. The combination of glass pane and screw insert is referred to as a glass element in the context of this application. Glass elements are therefore intended for direct screwing to the bodyshell.

[0005] However, when screwing the glass elements to the bodyshell, especially when using large glass panes, there is a risk that the local stresses in the glass at the attachment points where the glass panes are attached to the corresponding bodyshell of the vehicle will become excessive, causing the glass to break. This problem is particularly acute when small air gaps (≥ 0.3 mm) exist at the contact points between the glass pane and the bodyshell, for example, due to manufacturing inaccuracies.

[0006] It is known from the prior art, for example from DE 3624621 A1, to insert an elastic intermediate washer between a glass pane and a screw-connected counterpart. This intermediate washer reduces stress peaks in the glass and thus reduces the risk of glass breakage. KR 20130019832 A also teaches the provision of a through hole in the glass to allow the application of stability-enhancing, mostly elastic elements to the glass pane from both sides, thus reducing the stresses in the glass under load. Both techniques are only partially applicable to vehicle construction.

[0007] DE 10 2017 120 028 A1 and WO 2021 / 008 728 A1 show further prior art.

[0008] Given the described prior art, the object of the present invention is to provide a screw insert that serves to easily attach a glass pane to a rigid support, such as in the body shell of a vehicle, and reduces the stresses within the glass pane that occur during the transmission of force from the screw connection. Furthermore, the object is to provide a glass element comprising the screw insert according to the invention, a vehicle comprising the glass element according to the invention, and a method for producing the glass element according to the invention.

[0009] The object is achieved by the subject matter and method according to the independent claims. Advantageous developments of the invention are contained in the subclaims.

[0010] The screw insert according to the invention for fastening a glass pane to a rigid support, such as in particular in the bodyshell of a (motor) vehicle, has at least one screw-in sleeve with an internal thread, wherein a screw provided for fastening can be screwed into the internal thread. A screw-in sleeve is understood to mean an element of any shape with an internal thread. Furthermore, the screw insert according to the invention has a fastening structure arranged around the screw-in sleeve. This fastening structure, in turn, has a flat-shaped force distribution section, which is designed to transfer a force introduced into the screw-in sleeve to the largest possible area of ​​the glass pane. The term "flat-shaped" is understood to mean an element shape in which the thickness of the element is a maximum of one-tenth of the width or length of the element (whichever is smaller).

[0011] The flat-shaped force distribution section ensures that the force transmitted by the screw connection to the screw-in sleeve is distributed over a larger area of ​​the glass, thus reducing the stresses in the glass. This can reduce stresses in the glass and thus the risk of glass breakage.

[0012] Preferably, the area of ​​the force distribution section is at least 3 times, more preferably at least 5 times, and particularly preferably at least 10 times the area of ​​the screw-in sleeve. The area of ​​the screw-in sleeve or the force distribution section is understood to be the area that extends parallel to the glass pane in the corresponding components, for whose fastening the screw insert is intended.

[0013] In a preferred embodiment of the invention, the force distribution section has at least one rib, which extends in particular parallel to the main direction of extension of the force distribution section. The main direction of extension is to be understood as the spatial direction along which the force distribution section extends the longest. A rib increases the surface area of ​​the screw insert so that when the screw insert is attached to the glass pane by overmolding, the glass pane connects better to the screw insert. This allows the screw insert to be gripped and fastened more securely by the overmolding. Secondly, ribs can be used to improve the flow around the overmolding material, particularly at high injection pressures of more than 150 bar. In addition, ribs increase the stability of the screw insert in terms of flexural rigidity.In a further preferred embodiment of the invention, the at least one rib has a shape and / or a position on the force distribution section that is optimized with regard to the flow around the overmolding material. Thus, the at least one rib has a shape or position on the force distribution section that allows for a particularly favorable flow around the overmolding material, ensuring that as few air pockets as possible are present in the overmolding, thus enabling optimized fastening of the screw insert in the overmolding and on the glass pane.

[0014] Furthermore, the fastening structure of the screw insert preferably has at least one holding section. This is provided, in particular, in the form of a female part of a plug-in connection. A holding section is provided to secure the screw insert to the glass pane during fastening, in particular during overmolding. This also ensures that the screw insert does not touch the glass pane, since it can be held by means of holding elements provided corresponding to the holding sections and does not have to be placed on the glass pane.

[0015] According to the invention, the force distribution section of the screw insert has a trapezoidal shape, wherein this shape is in particular isosceles. The trapezoidal, in particular isosceles trapezoidal, force distribution section allows a controlled flow around the screw insert with little air inclusions, thus ensuring a high-quality attachment of the screw insert to the glass pane. In addition, a trapezoidal force distribution section has particularly favorable properties with regard to the force introduction into the glass pane, in particular because the available installation space can be used to the best possible extent when installing a glass pane as a vehicle roof. Furthermore, the trapezoidal shape also enables good centering of the screw insert when it is attached to the glass pane by overmolding.This is particularly advantageous at high injection pressures of the overmolding material of more than 150 bar.

[0016] Advantageously, the screw insert has an axially symmetrical shape. A symmetrical shape supports a uniform force transfer into the glass, thus reducing the risk of locally occurring high stresses.

[0017] Another advantageous embodiment of the invention is one in which the fastening structure is made of plastic. Plastic is an inexpensive, easy-to-process raw material that is highly suitable for the intended use.

[0018] The glass element according to the invention for fastening to a rigid support, in particular to a rigid support in a body shell for a motor vehicle, has a glass pane and a screw insert according to the invention, wherein the screw insert is fastened to the glass pane by means of an overmolding.

[0019] The vehicle according to the invention has a bodyshell and a glass element according to the invention, wherein the glass element is fastened to a rigid support of the bodyshell by means of at least one screw insert according to the invention.

[0020] According to the inventive method for producing the glass element according to the invention, a glass pane is first inserted and positioned in a tool provided for this purpose. The screw insert according to the invention is then placed in a designated position, wherein this position is selected such that the screw insert does not touch the glass pane and wherein the screw insert is held in this position by a holding element of the tool that engages in a holding section of the screw insert. In a further step, the screw insert is overmolded with an overmolding material, wherein the overmolding thus formed connects the screw insert to the glass pane.

[0021] In an advantageous embodiment of the method according to the invention, the overmolding of the screw insert is carried out in such a way that the space between the screw insert and the glass pane is filled by the overmolding. This allows for a particularly uniform force introduction through the screw insert and a particularly stable fastening of the screw insert.

[0022] Preferably, the overmolding of the screw insert with the overmolding material takes place with an injection pressure of the overmolding material of at least 150 bar, preferably 200 bar.

[0023] It should be noted that the features formulated as device features can also be applied as process features to the method according to the invention and are hereby disclosed. The same applies analogously to process features that can be applied analogously to devices.

[0024] In the following, an embodiment of the invention and its advantageous aspects are explained in more detail with reference to the accompanying figures. The figures show: Fig. 1 schematic representation of a body shell 50 of a vehicle 1 in plan view Fig. 2 schematic representation of an embodiment of a screw insert 10 according to the invention in a perspective view Fig. 3 schematic representation of a cross section of a screw insert 10 according to the invention in the installed state in the transverse direction Fig. 4 schematic representation of a cross section of the screw insert 10 according to the invention in the installed state in the longitudinal direction

[0025] On Fig. 1 has already been discussed in detail with regard to the descriptions of the state of the art. Therefore, a repeated description can be omitted here.

[0026] Fig. Figure 2 shows a schematic representation of an embodiment of a screw insert 10 according to the invention in a perspective view. The screw insert 10 is designed for fastening by means of an overmolding 20 (see Fig. 3 and Fig. 4) on a glass pane 30. The screw insert 10 has a screw-in sleeve 13 with an internal thread 11 and a round cross-section, as well as a fastening structure 12. The fastening structure 12 comprises a frame 121, which in the embodiment shown radially completely surrounds the screw-in sleeve 13. Furthermore, the fastening structure 12 has a force distribution section 122, the function of which will be discussed in the further Fig. 3 and Fig. 4. Furthermore, holding sections 124 are provided on both sides of the screw-in sleeve 13. These holding sections interact with corresponding holding elements provided on a tool during the process of fastening the screw insert 10 to a glass pane 30 by means of overmolding 20, thus ensuring the fixation of the screw insert 10 in the tool and in a fixed position. Furthermore, the force distribution section 122 has a plurality of ribs 123, which increase the stability of the screw insert 10 and additionally ensure a higher-quality fastening of the screw insert 10 to a glass pane 30.

[0027] The force distribution section 122 and thus also the basic shape of the entire screw insert 10 is essentially trapezoidal, with the main extension direction of the screw insert 10 extending along the base sides of the trapezoid. Thus, the ribs 123 extend in the main extension direction of the screw insert 10. The trapezoidal shape of the force distribution section 122 simultaneously defines the "surface of the force distribution section 122". The parallel thereto and extending from the plane of the drawing of the Fig. The round surface of the screw-in sleeve 13 protruding from Fig. 3 is referred to in this application as the "surface of the screw-in sleeve 13." From this view of the embodiment of the screw insert 10 according to the invention, it is clear that the surface of the force distribution section 122 exceeds the surface of the screw-in sleeve by several times.

[0028] Fig. 3 shows a schematic representation of a cross section of the screw insert 10 according to the invention in the transverse direction in the installed state in a vehicle 1. The embodiment shown corresponds to the one already described with regard to Fig. 2, which is why the individual components of the screw insert 10 will not be discussed further. The screw insert 10 is surrounded by an overmolding 20, which firmly connects the screw insert 10 to a glass pane 30. By means of a screw 60, the glass element formed from the glass pane 30 and the screw insert 10 is fastened to a rigid support of a body shell 50 of a vehicle 1. The glass pane 30 forms the glass roof of the Fig. 1 shown vehicle, where the Fig. 3 extends in the transverse direction of the vehicle 1. It can be seen that the screw insert 10 does not touch the glass pane 30, but is always spaced from it by the overmolding 12.

[0029] Fig. 4 shows the same embodiment of the invention as Fig. 3, wherein the cross-section does not run in the transverse direction of the vehicle 1, but in the longitudinal direction. It can be seen that the screw insert 10 is arranged such that its main extension direction also points in the longitudinal direction of the vehicle.

[0030] If a force is now transmitted via the screw connection between the internal thread 11 and the screw 60 to the screw insert 10, more precisely to the screw-in sleeve 13, the geometry of the screw insert 10 allows the force to be transmitted to the glass pane 30 in such a way that the formation of stress peaks in the glass can be reduced and thus the risk of glass breakage can be reduced. An exemplary force flow is shown in Fig.4 is indicated by the dashed lines. While the force and thus the resulting stresses in the glass are greatest in the area of ​​the screw-in sleeve 13, they decrease further with increasing distance from the screw-in sleeve 13. Nevertheless, it is also possible to transfer force into the glass via the overmolding at more distant points of the force distribution section 122, whereby the maximum stresses in the glass at the level of the screw-in sleeve 13 can be reduced compared to a screw insert 10 without a corresponding force distribution section 122.

Claims

[1] Screw insert (10) for fastening a glass pane (30) to a rigid support, comprising a screw-in sleeve (13) with an internal thread (11), a fastening structure (12) arranged around the screw-in sleeve (13) having a force distribution section (122) which is trapezoidal and flat in shape, wherein the force distribution section (122) is designed to transmit a force introduced into the screw-in sleeve (13) to a surface of the glass pane (30). [2] Screw insert (10) according to the preceding claim, wherein the area of ​​the force distribution section (122) is at least 3 times, preferably 5 times, particularly preferably 10 times as large as the area of ​​the screw-in sleeve (13). [3] Screw insert (10) according to one of the preceding claims, wherein the force distribution section (122) has at least one rib (123) which extends in particular parallel to a main extension direction of the force distribution section (122). [4] Screw insert (10) according to the preceding claim, wherein the at least one rib (123) has a shape and / or a position which is optimized with regard to the flow around it by an overmolding material. [5] Screw insert (10) according to one of the preceding claims, wherein the fastening structure (12) has at least one holding section (124), in particular in the form of a female part of a plug connection. [6] Screw insert (10) according to one of the preceding claims, wherein the shape of the force distribution section (122) is isosceles. [7] Screw insert (10) according to one of the preceding claims, wherein the fastening structure (12) is made of plastic. [8] Glass element for attachment to a rigid support, comprising a glass pane (30) and a screw insert (10) according to one of the preceding claims, wherein the screw insert (10) is attached to the glass pane (30) by means of an overmolding (20). [9] Vehicle (1) comprising a bodyshell (50) and a glass element according to the preceding claim, wherein the glass element is fastened to a rigid support of the bodyshell (50) by means of at least one screw insert (10) according to one of the preceding claims 1 to 7. [10] A method for producing a glass element according to claim 8 comprising a screw insert (10) according to claim 5, comprising the following steps, Inserting a glass pane (30) into a tool provided for this purpose, Placing the screw insert (10) according to claim 5 at a position provided for it, wherein the screw insert (10) does not touch the glass pane (30) in this position and wherein the screw insert (10) is held in this position by a holding element of the tool engaging in a holding section (124) of the screw insert (10), Overmolding the screw insert (10) with an overmolding material, wherein the overmolding (20) thus formed connects the screw insert (10) to the glass pane (30). [11] Method according to the preceding claim, wherein the overmolding of the screw insert (10) is carried out in such a way that the space between the screw insert (10) and the glass pane (30) is filled by the overmolding (20).

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